Infection Flashcards
(202 cards)
1
Q
Inactivated vaccines involve giving a killed version of the pathogen. They cannot cause an infection and are safe for immunocompromised patients, although they may not have an adequate response. Examples are?
A
Polio
Flu vaccine
Hepatitis A
Rabies
2
Q
Are inactivated vaccines safe in immunocompromised patients?
A
They cannot cause an infection and are safe for immunocompromised patients, although they may not have an adequate response.
3
Q
Subunit and conjugate vaccines only contain parts of the organism used to stimulate an immune response. They also cannot cause infection and are safe for immunocompromised patients. Examples of subunit and conjugate vaccines are?
A
Pneumococcus
Meningococcus
Hepatitis B
Pertussis (whooping cough)
Haemophilus influenza type B
Human papillomavirus (HPV)
Shingles (herpes-zoster virus)
4
Q
What are subunit and conjugate vaccines?
A
Subunit and conjugate vaccines only contain parts of the organism used to stimulate an immune response.
They also cannot cause infection and are safe for immunocompromised patients.
5
Q
Live attenuated vaccines contain a weakened version of the pathogen. They are still capable of causing infection, particularly in immunocompromised patients.
What are ecamples?
A
Measles, mumps and rubella vaccine: contains all three weakened viruses
BCG: contains a weakened version of tuberculosis
Chickenpox: contains a weakened varicella-zoster virus
Nasal influenza vaccine (not the injection)
Rotavirus vaccine
6
Q
Which types of vaccinations cannot cause infection and are therefore safe in immunocomprimised patients?
A
Inactivated vaccines
Subunit and conjugate vaccines
Toxin vaccines
7
Q
How do toxin vaccines work and what are examples?
A
Toxin vaccines contain a toxin that is normally produced by a pathogen. They cause immunity to the toxin and not the pathogen itself. Examples are the diphtheria and tetanus vaccines.
8
Q
At what ages are vaccines required?
A
8 weeks
12 weeks
16 weeks
1 year
Yearly from ages 2-8
3 years 4 months
12-13 years
14 years
9
Q
What vaccines are given at 8 weeks?
A
6 in 1 vaccine (diphtheria, tetanus, pertussis, polio, haemophilus influenzae type B (Hib) and hepatitis B)
Meningococcal type B
Rotavirus (oral vaccine)
10
Q
What vaccines are given at 12 weeks?
A
6 in 1 vaccine (again)
Pneumococcal (13 different serotypes)
Rotavirus (again)
11
Q
What vaccines are given at 16 weeks?
A
6 in 1 vaccine (again)
Meningococcal type B (again)
12
Q
What vaccines are given at 1 year?
A
2 in 1 (haemophilus influenza type B and meningococcal type C)
Pneumococcal (again)
MMR vaccine (measles, mumps and rubella)
Meningococcal type B (again)
13
Q
Which vaccine is given yearly at 2-8 years?
A
Influenza vaccine (nasal vaccine)
14
Q
What vaccines are given at 3 years and 4 months?
A
4 in 1 (diphtheria, tetanus, pertussis and polio)
MMR vaccine (again)
15
Q
What vaccine is given at 12-13 years?
A
Human papillomavirus (HPV) vaccine (2 doses given 6 to 24 months apart)
16
Q
Which vaccines are given at 14 years?
A
3 in 1 (tetanus, diphtheria and polio)
Meningococcal groups A, C, W and Y
17
Q
When is the 6 in 1 vaccine (diphtheria, tetanus, pertussis, polio, haemophilus influenzae type B (Hib) and hepatitis B) given?
A
8 weeks, 12 weeks, 16 weeks,
18
Q
When is the Meningococcal type B vaccine given?
A
8 weeks, 16 weeks, 1 year
19
Q
When is the MMR vaccine given?
A
1 year
3 years 4 months
20
Q
When is the Rotavirus vaccine given?
A
8 weeks, 12 weeks
21
Q
When is the pneumococcal vaccine given?
A
12 weeks, 1 year
22
Q
When and to whom is the BCG vaccination offered?
A
The BCG vaccine is offered from birth to babies who are at higher risk of tuberculosis.
These are babies with relatives from countries of high TB prevalence or who live in urban areas with a high rate of TB.
It may also be given to children arriving from areas of high TB prevalence or in close contact with people that have TB.
23
Q
The current NHS HPV vaccine is Gardasil, which strains does this protect against?
A
Strains 6 and 11 cause genital warts
Strains 16 and 18 cause cervical cancer
24
Q
Counselling parents on the HPV vaccination?
A
They are often upset because they believe this implies their daughter or son is sexually promiscuous.
Focus on the fact it needs to be given before they become sexually active and that it protects them from cervical cancer and genital warts.
HPV is very common and infection is the number one risk factor for cervical cancer.
25
What type of evidence supported the link between MMR and Autism?
Anecdotal
26
What is sepsis?
Sepsis is a syndrome that occurs when an infection causes the child to become systemically unwell.
It is the result of a severe systemic inflammatory response.
It is a life threatening condition and there should be a low threshold for treating suspected sepsis.
27
Pathophysiology of sepsis
The causative pathogens are recognised by macrophages, lymphocytes and mast cells.
These cells release vast amounts of cytokines, such as interleukins and tumor necrosis factor, to alert the immune system to the invader.
These cytokines activate other parts of the immune system.
This immune activation leads to further release of chemicals such as nitrous oxide that causes vasodilation.
The immune response causes inflammation throughout the body.
Many of these cytokines cause the endothelial lining of blood vessels to become more permeable.
This causes fluid to leak out of the blood into the extracellular space, leading to oedema and a reduction in intravascular volume.
The oedema around blood vessels creates a space between the blood and the tissues, reducing the amount of oxygen that reaches the tissues.
Activation of the coagulation system leads to deposition of fibrin throughout the circulation, further compromising organ and tissue perfusion.
It also leads to consumption of platelets and clotting factors, as they are being used up to form the blood clots.
This leads to thrombocytopenia, haemorrhages and an inability to form clots and stop bleeding.
This is called disseminated intravascular coagulopathy (DIC).
Blood lactate rises as a result of anaerobic respiration in the hypo-perfused tissues with an inadequate oxygen.
A waste product of anaerobic respiration is lactate.
28
What is septic shock?
Septic shock is diagnosed when sepsis has lead to cardiovascular dysfunction.
The arterial blood pressure falls, resulting in organ hypo-perfusion.
This leads to a rise in blood lactate as the organs begin anaerobic respiration.
29
How is septic shock treated?
Septic shock should be treated aggressively with IV fluids to improve the blood pressure and tissue perfusion.
If IV fluid boluses fail to improve the blood pressure and lactate level, children should be escalated to the high dependency or intensive care unit where inotropes (such as noradrenalin) can be considered.
Inotropes stimulate the cardiovascular system and improve blood pressure and tissue perfusion.
30
What is the role of inotropes in HDU/ITU management of septic shock?
Inotropes stimulate the cardiovascular system and improve blood pressure and tissue perfusion.
31
Signs of paediatric sepsis?
Deranged physical observations
Prolonged capillary refill time (CRT)
Fever or hypothermia
Deranged behaviour
Poor feeding
Inconsolable or high pitched crying
High pitched or weak cry
Reduced consciousness
Reduced body tone (floppy)
Skin colour changes (cyanosis, mottled pale or
ashen)
32
What is meant by shock?
Shock involves circulatory collapse and hypoperfusion of organs.
33
There are NICE guidelines from 2019 that cover the assessment of children under 5 year with a fever. They recommend using a traffic light system for the assessment of serious illness in these children. This categorises children as green (low risk), amber (intermediate risk) or red (high risk). Read through the table in the NICE guidelines describing the features of each to familiarise yourself with the signs to look out for.
Patients are categorised based on examination findings in various systems, such as?
Colour: normal colour versus cyanosis, mottled pale or ashen
Activity: active, happy and responsive versus abnormal responses, drowsy or inconsolable cry
Respiratory: normal breathing versus respiratory distress, tachypnoea or grunting
Circulation and hydration: normal skin and moist membranes versus tachycardia, dry membranes or poor skin turgor
Other: other concerning signs, such as fever > 5 days, non blanching rash, seizures or high temperatures < 6 months
34
All infants under what age with a temperature of 38ºC or above need to be treated urgently for sepsis, until proven otherwise?
3 months
35
All infants under 3 months with a temperature of what need to be treated urgently for sepsis, until proven otherwise.
38 degrees Celsius or above
36
Paediatric sepsis - immediate management?
Give oxygen if the patient has evidence of shock or oxygen saturations are below 94%
Obtain IV access (cannulation)
Blood tests, including a FBC, U&E, CRP, clotting screen (INR), blood gas for lactate and acidosis
Blood cultures, ideally before giving antibiotics
Urine dipstick and laboratory testing for culture and sensitivities
Antibiotics according to local guidelines. They should be given within 1 hour of presentation.
IV fluids. 20ml/kg IV bolus of normal saline if the lactate is above 2 mmol/L or there is shock. This may be repeated.
37
Paediatric sepsis further management following initial management?
Chest xray if pneumonia is suspected
Abdominal and pelvic ultrasound if intra-abdominal infection is suspected
Lumbar puncture if meningitis is suspected
Meningococcal PCR blood test if meningococcal disease is suspected
Serum cortisol if adrenal crisis is suspected
Continue antibiotics for 5 – 7 days if a bacterial
infection is suspected or confirmed.
Alter the antibiotic choice and duration once a source of infection is found and an organism is isolated.
Bacterial culture and sensitivities can be very helpful in guiding antibiotics.
A microbiologist can provide advice on the choice and duration of antibiotics.
Consider stopping antibiotics where there is a low suspicion of bacterial infection, the patient is well and blood cultures and two CRP results are negative at 48 hours.
38
When should you consider stopping antibiotics in ?paediatric sepsis?
Low suspicion of bacterial infection,
Patient is well and blood cultures
Two CRP results are negative at 48 hours
39
What is infectious mononucleosis and what causes it?
Infectious mononucleosis (IM) is a condition caused by infection with the Epstein Barr virus (EBV).
It is commonly known as the “kissing disease”, “glandular fever” or “mono”.
This virus is found in the saliva of infected individuals.
Infection may be spread by kissing or by sharing cups, toothbrushes and other equipment that transmits saliva.
EBV is secreted in the saliva of infected individuals and can be infectious several weeks before the illness begins and intermittently for the remainder of the patient’s life.
40
Is infection with mononucleosis usually symptomatic?
Most people are infected with EBV as children, when it causes very few symptoms.
When infection occurs in teenagers or young adults, it causes more severe symptoms.
It is the symptomatic infection with EBV that is called infectious mononucleosis.
Typical symptoms are fever, sore throat and fatigue.
41
When are patients infectious with EBV?
EBV is secreted in the saliva of infected individuals and can be infectious several weeks before the illness begins and intermittently for the remainder of the patient’s life.
42
What might you suspect in an adolescent with a sore throat, who develops an itchy rash after taking amoxicillin?
Mononucleosis
EBV infection causes an intensely itchy maculopapular rash in response to amoxicillin or cefalosporins
43
Features of EBV infection?
Fever
Sore throat
Fatigue
Lymphadenopathy (swollen lymph nodes)
Tonsillar enlargement
Splenomegaly and in rare cases splenic rupture
44
In infectious mononucleosis, the body produces something called heterophile antibodies - what are these and when are they formed?
Antibodies that are more multipurpose and not specific to the EBV antigens.
It takes up to 6 weeks for these antibodies to be produced.
45
Which tests can be used to detect hetrophile antibodies?
Monospot test: this introduces the patient’s blood to red blood cells from horses. Heterophile antibodies (if present) will react to the horse red blood cells and give a positive result.
Paul-Bunnell test: this is similar to the monospot test but uses red blood cells from sheep.
46
Heterophile antibodies in ?IM - sensitivity and specificity
Almost 100% specific for infectious mononucleosis, however not everyone who has IM produces heterophile antibodies, and it can take up to six weeks for the antibodies to be produced. Therefore they are only 70 – 80% sensitive.
47
EBV - specific antibody tests?
The IgM antibody rises early and suggests acute infection
The IgG antibody persists after the condition and suggests immunity
48
Management and prognosis of infectious mononucleosis?
Infectious mononucleosis is usually self limiting. The acute illness lasts around 2 – 3 weeks, however it can leave the patient with fatigue for several months once the infection is cleared.
Patients are advised to avoid alcohol, as EBV impacts the ability of the liver to process the alcohol.
Patients are advised to avoid contact sports due to the risk of splenic rupture.
Emergency surgery is usually required if splenic rupture occurs.
49
Potential complications of infectious mononucleosis?
Splenic rupture
Glomerulonephritis
Haemolytic anaemia
Thrombocytopenia
Chronic fatigue
50
EBV infection is associated with certain cancers, for example?
Burkitt’s lymphoma.
51
What is HIV, what is AIDS?
HIV refers to the human immunodeficiency virus that causes the infection that makes someone HIV positive.
AIDS refers to the acquired immunodeficiency syndrome that occurs at the end stages of a HIV infection, once the infection has affected the immune system enough to make the person susceptible to recurrent and unusual infections.
AIDS is usually referred to in the UK as late stage HIV.
52
Basic pathophysiology of HIV?
HIV is an RNA retrovirus. HIV-1 is most common type. HIV-2 is rare outside West Africa.
The virus enters and destroys the CD4 T helper cells.
An initial seroconversion flu like illness occurs within a few weeks of infection.
The infection is then asymptomatic until it progresses and the patient becomes immunocompromised and beings developing AIDS defining illnesses and opportunistic infections, potentially years later.
53
How is HIV spread?
Unprotected anal, vaginal or oral sexual activity
Mother to child at any stage of pregnancy, birth or breastfeeding. This is referred to as vertical transmission.
Mucous membrane, blood or open wound exposure to infected blood or bodily fluids. This could be through sharing needles, needle-stick injuries or blood splashed in an eye.
54
How is mode of delivery determined to prevent HIV transmission to the baby in a mother who is HIV positive?
Normal vaginal delivery is recommended for women with a viral load < 50 copies / ml
Caesarean sections are considered in patients with > 50 copies copies / ml and in all women with > 400 copies / ml
IV zidovudine should be given during the caesarean if the viral load is unknown or there are > 10000 copies / ml
55
When should IV zidovudine be given to prevent HIV during c section?
IV zidovudine should be given during the caesarean if the viral load is unknown or there are > 10000 copies / ml
56
Under what viral loads is considered 'safe' for a vaginal delivery in terms of vertical HIV transmission?
< 50 copies / ml
57
What influences what prophylaxis treatment may be given to the baby born to a mother who is HIV positive?
High risk vs low risk - determined by viral load
High risk: mother has < 50 copies / ml
Low risk: mother has > 50 / ml
58
Prophylaxis of HIV following birth for a baby born to a mother with viral load of < 50 copies / ml
zidovudine for 4 weeks
59
Prophylaxis of HIV following birth for a baby born to a mother with viral load of > 50 copies / ml
zidovudine, lamivudine and nevirapine for 4 weeks
60
For how long following birth are babies born to mothers with HIV given prophylactic treatment?
4 weeks
61
HIV and breastfeeding?
HIV can be transmitted during breastfeeding, even if the mother’s viral load is undetectable.
Breastfeeding is never recommended for mothers with HIV, however if the mum is adamant and the viral load is undetectable, sometimes it is attempted with close monitoring by the HIV team.
62
What options exist for HIV testing?
HIV antibody screen: this tests whether the immune system has created antibodies due to exposure to the HIV virus. This is the standard screening test, but it can give false positive in babies of HIV positive mums, due to maternal antibodies that cross the placenta. It can take up to 3 months for antibodies to develop after exposure to the virus.
HIV viral load: this tests directly for viruses in the blood. This will never be falsely positive, but may come back as “undetectable” in patients on antiretroviral therapy.
63
Problem with HIV antibody screen in a baby, and why it occurs?
It can give false positive in babies of HIV positive mums, due to maternal antibodies that cross the placenta. It can take up to 3 months for antibodies to develop after exposure to the virus.
64
When screening a child for HIV, what are is the advantage and disadvantage of viral load testing?
This will never be falsely positive (unlike in antibody screen, where maternal antibodies may cross placenta), but may come back as “undetectable” in patients on antiretroviral therapy.
65
When to test children for HIV?
Babies to HIV positive parents
When immunodeficiency is suspected, for example where there are unusual, severe or frequent infections
Young people who are sexually active can be offered testing if there are concerns
Risk factors such as needle stick injuries, sexual abuse or IV drug use
66
Babies to HIV positive parents are tested how and when?
HIV viral load test at 3 months. If this is negative, the child has not contracted HIV during birth and will not develop HIV unless they have further exposure.
HIV antibody test at 24 months. This is to assess whether they have contracted HIV since their 3 month viral load, for example through breast feeding. If the 3 month test is negative and they are not breastfed, this should be negative.
67
Management of HIV in children?
Treatment should be coordinated by a specialist in paediatric HIV. The key principles of medical care are:
Antiretroviral therapy (ART) to suppress the HIV infection
Normal childhood vaccines, avoiding or delaying live vaccines if severely immunosuppressed.
Prophylactic co-trimoxazole (Septrin) for children with low CD4 counts, to protect against pneumocystis jirovecii pneumonia (PCP)
Treatment of opportunistic infections
The aim of antiretroviral therapy (ART) is to achieve a normal CD4 count and undetectable viral load. As a general rule, when a patient has a normal CD4 and undetectable viral load on ART, treat their physical health problems (e.g. routine chest infections) as you would an HIV negative patient. When prescribing medications check for interactions with the HIV therapy.
The paediatric HIV multidisciplinary team should be involved in:
Regular follow up to monitor growth and development
Dietician input for nutritional support when required
Parental education about the condition
Disclosing the diagnosis to the child is often delayed until they are mature enough
Psychological support
Specific sex education in relation to HIV when appropriate
68
In childhood HIV, treatment should be coordinated by a specialist in paediatric HIV. The key principles of medical care are what?
Antiretroviral therapy (ART) to suppress the HIV infection
Normal childhood vaccines, avoiding or delaying live vaccines if severely immunosuppressed.
Prophylactic co-trimoxazole (Septrin) for children with low CD4 counts, to protect against pneumocystis jirovecii pneumonia (PCP)
Treatment of opportunistic infections
The aim of antiretroviral therapy (ART) is to achieve a normal CD4 count and undetectable viral load. As a general rule, when a patient has a normal CD4 and undetectable viral load on ART, treat their physical health problems (e.g. routine chest infections) as you would an HIV negative patient.
When prescribing medications check for interactions with the HIV therapy.
69
What is mumps?
Mumps is a viral infection spread by respiratory droplets. The incubation period is 14 – 25 days. Mumps is usually a self limiting condition that lasts around 1 week. Management is supportive, and involves treating the complications if they occur.
70
How is mumps spread?
Respiratory droplets
71
What is the incubation period of mumps?
14-25 days
72
Usual course of mumps?
Incubation 14-25 days
1 week of self limiting symptoms
73
What aspect of the history is essentiel when considering ?mumps?
Taking a vaccination history is essential when considering a diagnosis of mumps. The MMR vaccine offers around 80% protection against mumps.
74
How does mumps present?
Patients experience an initial period of flu-like symptoms known as the prodrome. These occur a few days before the parotid swelling:
Fever
Muscle aches
Lethargy
Reduced appetite
Headache
Dry mouth
Parotid gland swelling, either unilateral or bilateral, with associated pain is the key feature that should make you consider mumps.
It can also present with symptoms of the complications, such as:
Abdominal pain (pancreatitis)
Testicular pain and swelling (orchitis)
Confusion, neck stiffness and headache (meningitis or encephalitis)
75
Potential symptoms of the complications of mumps?
Abdominal pain (pancreatitis)
Testicular pain and swelling (orchitis)
Confusion, neck stiffness and headache (meningitis or encephalitis)
76
Management of mumps?
The diagnosis can be confirmed using PCR testing on a saliva swab. The blood or saliva can also be tested for antibodies to the mumps virus.
Mumps is a notifiable disease, meaning you need to notify public health of any suspected and confirmed cases.
Management is supportive, with rest, fluids and analgesia. Mumps is a self limiting condition. Management of complications is also mostly supportive.
77
Complications of mumps?
Pancreatitis
Orchitis
Meningitis
Sensorineural hearing loss
78
What is hepatitis B and how is it spread?
Hepatitis B is a DNA virus. It is transmitted by direct contact with blood or bodily fluids.
This may occur during sexual intercourse or sharing needles, for example amongst IV drug users or tattoos. It can also be passed through sharing contaminated household products such as toothbrushes or contact between minor cuts or abrasions.
It can also be passed from mother to child during pregnancy and delivery. This is known as vertical transmission.
79
How does hepatitis B infection affect children differently from adults?
Most children fully recover from the infection within 2 months, however a portion go on to become chronic hepatitis B carriers. In these patients the virus DNA has integrated into their own DNA and they continue to produce the viral proteins. The risk of developing chronic hepatitis B after exposure is:
90% for neonates
30% for children under 5
Under 10% for adolescents
Most children with chronic hepatitis B are asymptomatic, with normal growth and development and normal liver function tests.
Less than 5% will develop liver cirrhosis and less than 0.05% will develop hepatocellular carcinoma before adulthood.
These risks increase once they enter adulthood.
80
What are the different antigens and antibodies tested for in relation to Hep B and what do they indicate?
Surface antigen (HBsAg) – active infection
E antigen (HBeAg) – marker of viral replication and implies high infectivity
Core antibodies (HBcAb) – implies past or current infection
Surface antibody (HBsAb) – implies vaccination or past or current infection
Hepatitis B virus DNA (HBV DNA) – this is a direct count of the viral load
81
What does HbsAg + indicate?
active infection
82
What does E antigen (HBeAg) + indicate?
marker of viral replication and implies high infectivity
83
What does HBcAb + indicate?
past or current infection
84
What does HBsAb + indicate?
vaccination, past or current infection
85
Diagnosing hepatitis B
When screening for hepatitis B, test HBcAb (for previous infection) and HBsAg (for active infection).
If these are positive do further testing for HBeAg and viral load (HBV DNA).
86
Which antibody can help distinguish between acute, chronic and past hepatitis B infection?
HBcAb
We can measure IgM and IgG versions of the HBcAb.
IgM implies an active infection and will give a high titre with an acute infection and a low titre with a chronic infection.
IgG indicates a past infection where the HBsAg is negative.
87
Why is HBeAg important in ?Hep C?
Where the HBeAg is present it implies the patient is in an acute phase of the infection where the virus is actively replicating.
The level of HBeAg correlates with their infectivity.
If the HBeAg is higher, they are highly infectious to others.
When they HBeAg is negative but the HBeAb is positive, this implies they have been through a phase where the virus was replicating but the virus has now stopped replicating and they are less infectious.
88
Which children should be screened for Hepatitis B?
Children of hepatitis B positive mums (screen at 12 months of age or any time after that)
Migrants from endemic areas
Close contacts of patients with hepatitis B
89
After what age should children of hepatitis B positive mothers?
12 months or after
90
How is the risk of hep B in a baby born to a hep B + mother reduced?
To reduce the risk of the baby contracting hepatitis B, at birth (within 24 hours) neonates with hepatitis B positive mothers should be given both:
Hepatitis B vaccine
Hepatitis B immunoglobulin infusion
Infants are given an additional hepatitis B vaccine at 1 and 12 months of age.
They will also receive the hepatitis B vaccine as part of the normal 6 in 1 vaccine given to all infants aged 8, 12 and 16 weeks.
They are tested for the HBsAg at 1 year to see if they have contracted hepatitis B.
91
Hepatitis B and breastfeeding?
The hepatitis B virus can be found in the breast milk of mothers with hepatitis B.
Babies of these mothers have already been exposed to the virus during pregnancy and birth.
They should also receive the hepatitis B vaccine and hepatitis B immunoglobulin infusion.
Therefore, the general advice is that it is safe for hepatitis B positive mother to breastfeed provided their babies are properly vaccinated.
92
Hep B vaccination?
Vaccination involves injecting the hepatitis B surface antigen. The vaccine requires 3 doses at different intervals. Vaccination to hepatitis B is now included as part of the UK routine vaccination schedule as part of the 6 in 1 vaccine.
93
Management of hepatitis B in children?
Most children with chronic hepatitis B are asymptomatic and do not require treatment.
They require regular specialist follow up to assess monitor their serum ALT, HbeAg, HBV DNA, physical examination and liver ultrasound.
Where there is evidence of hepatitis or cirrhosis, treatment with antiviral medications may be considered.
94
What scores on PEWS?
Nurse/family concern
Reduced or increased RR
Moderate/Severe respiratory distress
Oxygen requirement
Reduced or increased HR
Decreased conciousness level
95
What is meningitis?
Meningitis is defined as inflammation of the meninges. The meninges are the lining of the brain and spinal cord. This inflammation is usually due to a bacterial or viral infection.
96
What bacteria is commonly known as meningococcus?
Neisseria meningitidis is a gram-negative diplococcus bacteria
They are circular bacteria (cocci) that occur in pairs (diplo-)
97
What is meningococcal septicaemia?
Meningococcal septicaemia refers to the meningococcus bacterial infection in the bloodstream.
Meningococcal refers to the bacteria and septicaemia refers to infection in the blood stream.
Meningococcal septicaemia is the cause of the classic “non-blanching rash” that everybody worries about.
This rash indicates the infection has caused disseminated intravascular coagulopathy (DIC) and subcutaneous haemorrhages.
98
Meningococcal septicaemia is the cause of the classic “non-blanching rash” - why?
This rash indicates the infection has caused disseminated intravascular coagulopathy (DIC) and subcutaneous haemorrhages.
99
What are the most common cause of bacterial meningitis in children and adults??
Neisseria meningitidis (meningococcus) and Streptococcus pneumoniae (pneumococcus).
100
Most common cause of bacterial meningitis in neonates?
In neonates the most common cause is group B strep (GBS). GBS is usually contracted during birth from GBS bacteria that live harmlessly in the mother’s vagina.
101
NICE recommend a lumbar puncture as part of the investigations for all children under fitting what criteria?
Under 1 month presenting with fever
1 to 3 months with fever and are unwell
Under 1 year with unexplained fever and other features of serious illness
102
How does meningitis present?
Typical symptoms of meningitis:
fever
neck stiffness
vomiting, headache
photophobia
altered consciousness
seizures
Where there is meningococcal septicaemia children can present with a non-blanching rash. Other causes of bacterial meningitis do not usually cause the non-blanching rash.
Neonates and babies can present with very non-specific signs and symptoms, such as hypotonia, poor feeding, lethargy, hypothermia and a bulging fontanelle.
103
Neonates and babies with meningitis can present with very non-specific signs and symptoms, such as what?
hypotonia
poor feeding
lethargy
hypothermia
a bulging fontanelle
104
What tests can be used to identify meningeal irritation?
Kernig’s test
Brudzinski’s test
105
What does Kernig's test involve?
Kernig’s test involves lying the patient on their back, flexing one hip and knee to 90 degrees and then slowly straightening the knee whilst keeping the hip flexed at 90 degrees.
This creates a slight stretch in the meninges.
Where there is meningitis it will produce spinal pain or resistance to movement.
106
What does Brudzinski's test involve?
Brudzinski’s test involves lying the patient flat on their back and gently using your hands to lift their head and neck off the bed and flex their chin to their chest.
In a positive test (meningeal irritation) this causes the patient to involuntarily flex their hips and knees.
107
?bacterial meningitis in the community?
Children seen in the primary care setting with suspected meningitis AND a non blanching rash should receive an urgent stat injection (IM or IV) of benzylpenicillin prior to transfer to hospital, as time is so important. The dose will depending on their age.
Giving antibiotics should not delay transfer to hospital. Where there is a true penicillin allergy, transfer should be the priority rather than finding alternative antibiotics.
108
?bacterial meningitis in the hospital?
Ideally a blood culture and a lumbar puncture for cerebrospinal fluid (CSF) should be performed prior to starting antibiotics, however if the patient is acutely unwell antibiotics should not be delayed.
Send blood tests for meningococcal PCR if meningococcal disease is suspected. This tests directly for the meningococcal DNA. It can give a result quicker than blood culture depending on local services, and will still be positive after the bacteria has been treated with antibiotics.
There should be a low threshold for treating suspected bacterial meningitis, particularly in babies and younger children.
Always follow the local guidelines regarding the choice of antibiotic. Typical antibiotics are:
Under 3 months – cefotaxime plus amoxicillin (the amoxicillin is to cover listeria contracted during pregnancy)
Above 3 months – ceftriaxone
Vancomycin should be added to these antibiotics if there is a risk of penicillin resistant pneumococcal infection, for example recent foreign travel or prolonged antibiotic exposure.
Steroids are also used in bacterial meningitis to reduce the frequency and severity of hearing loss and neurological damage. Dexamethasone is given 4 times daily for 4 days to children over 3 months if the lumbar puncture is suggestive of bacterial meningitis.
Bacteria meningitis and meningococcal infection are notifiable diseases, so public health need to be informed of all cases.
109
Drug of choice for bacterial menigitis under 3 months
Under 3 months – cefotaxime plus amoxicillin (the amoxicillin is to cover listeria contracted during pregnancy)
110
Drug of choice for bacterial meningitis in children older
Above 3 months – ceftriaxone
111
Significant exposure to a patient with meningococcal infections such as meningitis or septicaemia puts people at risk of contracting the illness.
What post exposure prophylaxis may be given?
Post exposure prophylaxis is guided by public health. The usual antibiotic choice for this is a single dose of ciprofloxacin. It should be given as soon as possible and ideally within 24 hours of the initial diagnosis.
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When is the risk of bacterial meningitis high following exposure?
This risk is highest for people that have had close prolonged contact within the 7 days prior to the onset of the illness.
The risk decreases 7 days after exposure.
Therefore, if no symptoms have developed 7 days after exposure they are unlikely to develop the illness.
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Viral meningitis - common cause and management?
The most common causes of viral meningitis are herpes simplex virus (HSV), enterovirus and varicella zoster virus (VZV). A sample of the CSF from the lumbar puncture should be sent for viral PCR testing.
Viral meningitis tends to be milder than bacterial and often only requires supportive treatment.
Aciclovir can be used to treat suspected or
confirmed HSV or VZV infection.
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How are lumbar puncture samples used in ?meningitis?
Samples are sent for bacterial culture, viral PCR, cell count, protein and glucose.
A blood glucose sample should be sent at the same time so that it can be compared to the CSF sample. The samples need to be sent immediately.
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Lumbar puncture appearance: viral vs bacterial meningitis?
Cloudy - bacterial
Clear - viral
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Lumbar puncture protein: viral vs bacterial meningitis?
High - bacterial
Mildly raised or normal - viral
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Lumbar puncture glucose: viral vs bacterial meningitis
Low - bacterial
Normal - viral
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Lumbar puncture WCC: bacterial vs viral meningitis
High (neutrophils) - bacterial
High (lymphocytes) - viral
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Lumbar puncture culture: bacterial vs viral meningitis
Bacteria - bacterial
Negative - viral
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Meningitis: complications
Hearing loss is a key complication
Seizures and epilepsy
Cognitive impairment and learning disability
Memory loss
Cerebral palsy, with focal neurological deficits such as limb weakness or spasticity
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What is Hepatitis C and what are the implications of it?
Hepatitis C is an RNA virus. It is spread by blood and bodily fluids.
No vaccine is available. It is now curable in adults, using direct acting antiviral medications. These treatments are not yet available for children.
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Hepatitis C - disease course & complications in adults?
In adults:
1 in 4 fight off the virus and make a full recovery
3 in 4 develop chronic hepatitis C
Complications:
Liver cirrhosis and associated complications of cirrhosis
Hepatocellular carcinoma
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Vertical transmission of Hep C?
Hepatitis C is passed from infected mothers to their babies about 5 – 15% of the time. Hepatitis C antivirals are not recommended in pregnancy and there are no additional measures that are known to reduce the risk of transmission.
Babies and children tend not to have any symptoms or pathology associated with hepatitis C infection. It is very unlikely that children will pass on hepatitis C to others as they do not engage in sexual activity or IV drug use.
Parents should be educated about hepatitis C and the modes of transmission.
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Hepatitis C - testing
Hepatitis C antibody is the screening test
Hepatitis C RNA testing is used to confirm the diagnosis of hepatitis C, calculate viral load and identify the genotyp
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Management of hep C in children?
Babies to hepatitis C positive mothers are tested at 18 months of age using the hepatitis C antibody test. Breastfeeding has not been found to spread hepatitis C, so mothers are free to breastfeed their babies. If nipples become cracked or bleed breastfeeding should temporarily stop whilst they heal.
Children often clear the virus spontaneously. Chronic infection with hepatitis C does not usually cause issues in childhood. Infected children will require regular specialist follow up to monitor their liver function and hepatitis C viral load.
Medical treatment may be considered in children over 3 years. Treatment in childhood involves pegylated interferon and ribavirin, which are less effective and well tolerated compared with the adult treatments.
Treatment is typically delayed until adulthood unless the child is significantly affected, because children are usually asymptomatic and newly available treatment for adults is highly effective.
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Can mothers with hep C breast feed?
Breastfeeding has not been found to spread hepatitis C, so mothers are free to breastfeed their babies. If nipples become cracked or bleed breastfeeding should temporarily stop whilst they heal.
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How are Babies to hepatitis C positive mothers are tested?
at 18 months of age using the hepatitis C antibody test
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What is encephalitis?
Encephalitis means inflammation of the brain.
This can be the result of infective or non-infective causes.
Non-infective causes are autoimmune, meaning antibodies are created that target brain tissue.
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Causes of viral encephalitis?
The most common cause is infection with a virus.
Bacterial and fungal encephalitis is also possible although much more rare in the UK.
The most common viral cause is herpes simplex virus (HSV).
In children the most common cause is herpes simple type 1 (HSV-1) from cold sores.
In neonates it is herpes simplex type 2 (HSV-2) from genital herpes, contracted during birth.
Other viral causes include varicella zoster virus (VZV) associated with chickenpox, cytomegalovirus associated with immunodeficiency, Epstein-Barr virus associated with infectious mononucleosis, enterovirus, adenovirus and influenza virus.
It is important to ask about vaccinations, as the polio, mumps, rubella and measles viruses can cause encephalitis as well.
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Most common cause of encephalitis in children?
In children the most common cause is herpes simple type 1 (HSV-1) from cold sores.
In neonates it is herpes simplex type 2 (HSV-2) from genital herpes, contracted during birth.
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Most common cause of encephalitis in neonates?
In neonates it is herpes simplex type 2 (HSV-2) from genital herpes, contracted during birth.
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Presentation of encephalitis in children?
Altered consciousness
Altered cognition
Unusual behaviour
Acute onset of focal neurological symptoms
Acute onset of focal seizures
Fever
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Diagnosis of encephalitis in children?
Children with features of encephalitis need some key investigations to establish the diagnosis:
Lumbar puncture, sending cerebrospinal fluid for viral PCR testing
CT scan if a lumbar puncture is contraindicated
MRI scan after the lumbar puncture to visualise the brain in detail
EEG recording can be helpful in mild or ambiguous symptoms but is not always routinely required
Swabs of other areas can help establish the causative organism, such as throat and vesicle swabs
HIV testing is recommended in all patients with encephalitis
Contraindications to a lumbar puncture include a GCS below 9, haemodynamically unstable, active seizures or post-ictal.
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Contraindications to a lumbar puncture?
A GCS below 9
Haemodynamically unstable
Active seizures or post-ictal
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Management of encephalitis in children?
Intravenous antiviral medications are used to treat the suspected or confirmed underlying cause:
Aciclovir treats herpes simplex virus (HSV) and varicella zoster virus (VZV)
Ganciclovir treat cytomegalovirus (CMV)
Repeat lumbar puncture is usually performed to ensure successful treatment prior to stopping antivirals
Aciclovir is usually started empirically in suspected encephalitis until results are available. Other viral causes have no effective treatment and management is supportive.
Followup, support and rehabilitation is required after encephalitis, with help managing the complications.
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What viral causes of encephalitis can aciclovir be used to treat?
Aciclovir treats herpes simplex virus (HSV) and varicella zoster virus (VZV)
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What viral causes of encephalitis can Ganciclovir be used to treat?
Ganciclovir treat cytomegalovirus (CMV)
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Complications of Encephalitis
Lasting fatigue and prolonged recovery
Change in personality or mood
Changes to memory and cognition
Learning disability
Headaches
Chronic pain
Movement disorders
Sensory disturbance
Seizures
Hormonal imbalance
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What is Roseola infantum
Roseola infantum (also known as exanthem subitum, occasionally sixth disease) is a common disease of infancy caused by the human herpes virus 6 (HHV6). It has an incubation period of 5-15 days and typically affects children aged 6 months to 2 years.
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Roseola infantum incubation period
incubation period of 5-15 days
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What ages does roseola infantum affect?
aged 6 months to 2 years.
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Features of roseola infantum?
high fever: lasting a few days, followed later by a
maculopapular rash
Nagayama spots: papular enanthem on the uvula and soft palate
febrile convulsions occur in around 10-15%
diarrhoea and cough are also commonly seen
Other possible consequences of HHV6 infection
aseptic meningitis
hepatitis
School exclusion is not needed.
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Rubella: school exclusion
5 days from onset of rash
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Scarlet fever: school exclusion
24 hours after commencing antibiotics
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Hand foot and mouth: school exclusion
No exclusion required
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What is termed First disease?
First disease: Measles
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What is termed second disease?
Second disease: Scarlet Fever
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What is termed Third disease?
Third disease: Rubella (AKA German Measles)
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What is termed Fourth disease?
Fourth disease: Dukes’ Disease
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What is termed Fifth disease?
Fifth disease: Parvovirus B19
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What is termed Sixth Disease?
Sixth disease: Roseola Infantum
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What causes measles and how does it spread?
Measles virus.
It is highly contagious via respiratory droplets.
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How long after exposure do symptoms begin in measles?
10-12 days
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What are the initial symptoms of measles?
FEVER
CROYZAL SYMPTOMS
CONJUNCTIVITIS
Symptoms start 10 – 12 days after exposure,
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Symptom course in measles?
10 – 12 days after exposure:
- Fever
- Croyzal symptoms
- Conjuncivitis
2 days after fever:
- Koplik spots - greyish white spots on the buccal mucosa
3-5 days following fever:
The rash starts on the face, classically behind the ears, then spreading to the rest of the body.
The rash is an erythematous, macular rash with flat lesions.
Self limiting, resolves after around 7-10 days
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Isolation period in measles?
Until 4 days after their symptoms resolve.
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Measles - important considerations?
Children should be isolated until 4 days after their symptoms resolve.
Measles is a notifiable disease and all cases need to be reported to public health.
30% of patients with measles develop a complication.
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30% of patients with measles develop a complication - such as?
Pneumonia
Diarrhoea
Dehydration
Encephalitis
Meningitis
Hearing loss
Vision loss
Death
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Which of the “viral exanthemas” are notifiable disease?
First disease: Measles
Second disease: Scarlet Fever
Third disease: Rubella (AKA German Measles)
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What common infectious conditions should parents notify school/nursery of but do not require isolation?
Hand, foot and mouth
Glandular fever
Head lice
Tonsillitis
Threadworms
Slapped cheek
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What common infectious conditions should parents isolate children from school with?
Chickenpox
Diarrhoea and Vomiting
Cold and flu-like illness (including COVID-19)
Impetigo
Measles
Mumps
Scabies
Scarlet fever
Whooping cough
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Time off school/nursery: chickenpox
at least 5 days from the onset of the rash and until all blisters have crusted over
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Time off school/nursery: D&V
48 hours after their last episode
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Time off school/nursery: Cold and flu-like illness (including COVID-19)
They no longer have a high temperature and feel well enough to attend. Follow the national guidance if they’ve tested positive for COVID-19
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Time off school/nursery: impetigo
their sores have crusted and healed, or 48 hours after they started antibiotics
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Time off school/nursery: measles
4 days after the rash first appeared
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Time off school/nursery: mumps
5 days after the swelling started
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Time off school/nursery: scabies
until they’ve had their first treatment
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Time off school/nursery: scarlet fever
24 hours after they started taking antibiotics
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Time off school/nursery: Whooping cough
48 hours after starting abx
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Time off school/nursery: hand foot and mouth
Not required if child well enough but let school/nursery know about
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Time off school/nursery: hand foot and mouth
Not required if child well enough but let school/nursery know about
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Time off school/nursery: glandular fever
Not required if child well enough but let school/nursery know about
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Time off school/nursery: head lice
Not required if child well enough but let school/nursery know about
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Time off school/nursery: threadworms
Not required if child well enough but let school/nursery know about
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Time off school/nursery: tonsillitis
Not required if child well enough but let school/nursery know about
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Time off school/nursery: slapped cheek/parvovirus/fifths disease
Not required if child well enough but let school/nursery know about - no longer infectious once rash has appeared
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What causes Scarlet fever?
Scarlet fever is associated with group A streptococcus infection, usually tonsillitis. It is not caused by a virus.
Scarlet fever is caused by an exotoxin produced by the streptococcus pyogenes (group A strep) bacteria.
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What does a rough sandpaper rash which is spreading with flushed cheeks and strawberry tongue suggest?
Scarlett fever caused by an exotoxin produced by the streptococcus pyogenes (group A strep) bacteria.
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Signs of scarlet fever other than the rough sandpaper rash which is spreading?
Fever
Lethargy
Flushed face
Sore throat
Strawberry tongue
Cervical lymphadenopathy
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In addition to scarlet fever, patients can have other conditions associated with group A strep infection?
Post-streptococcal glomerulonephritis
Acute rheumatic fever
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How long after exposure to symptoms of rubella start?
Around 2 weeks
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What causes rubella and how does it spread?
Rubella is caused by the rubella virus. It is highly contagious and spread by respiratory droplets. S
183
Presentation of rubella?
It presents with a milder erythematous macular rash compared with measles.
The rash starts on the face and spreads to the rest of the body.
The rash classically lasts 3 days.
It can be associated with
Mild fever
Joint pain
Sore throat
Patients often have enlarged lymph nodes (lymphadenopathy) behind the ears and at the back of the neck.
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Management of rubella?
Management is supportive and the condition is self limiting.
Rubella is a notifiable disease and all cases need to be reported to public health.
Children should stay off school for at least 5 days after the rash appears.
Children should avoid pregnant women.
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Complications of rubella (directly affecting the infected patient)
Complications are rare, but include thrombocytopenia encephalitis
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Why are patients with rubella advised to avoid pregnant women?
Rubella is dangerous in pregnancy and can lead to congenital rubella syndrome, which is a triad of:
Deafness
Blindness
Congenital heart disease
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What names are used to describe parovirus b19 and what causes it?
Parvovirus B19 is also known as fifth disease, slapped cheek syndrome and erythema infectiosum. It is caused by the parvovirus B19 virus.
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Potential complications of Parovirus B19
Aplastic anaemia
Encephalitis or meningitis
Pregnancy complications including fetal death
Rarely hepatitis, myocarditis or nephritis
189
Patients that are at risk of complications of Parovirus 19 include who?
Patients that are at risk of complications include immunocompromised patients, pregnant women and patients with haematological conditions such as sickle cell anaemia, thalassaemia, hereditary spherocytosis and haemolytic anaemia.
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Patients at risk of complications of Parovirus 19 require what extra management?
These patients require serology testing for parvovirus to confirm the diagnosis and checking of the full blood count and reticulocyte count for aplastic anaemia.
People that would be at risk of complications that have come in contact with someone with parvovirus prior to the rash forming, should be informed and may need investigations.
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How does Parovirus 19 infection present?
Parvovirus infection starts with mild fever, coryza and non-specific viral symptoms such as muscle aches and lethargy.
After 2 – 5 days the rash appears quite rapidly as a diffuse bright red rash on both cheeks, as though they have “slapped cheeks”.
A few days later a reticular mildly erythematous rash affecting the trunk and limbs appears that can be raised and itchy. Reticular means net-like.
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Course of Parovirus 19
The illness is self limiting and the rash and symptoms usually fade over 1 – 2 weeks.
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Management of parovirus19
Healthy children and adults have a low risk of any complications and are managed supportively with plenty of fluids and simple analgesia.
It is infectious prior to the rash forming, but once the rash has formed they are no longer infectious and do not need to stay off school.
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What is roseola infantum and what causes it?
Roseola infantum is also known as just roseola or sixth disease. This is caused by human herpesvirus 6 (HHV-6) and less frequently by human herpesvirus 7 (HHV-7).
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Roseola infantum presentation?
It presents 1 – 2 weeks after infection with a high fever (up to 40ºC) that comes on suddenly, lasts for 3 – 5 days and then disappears suddenly.
There may be coryzal symptoms, sore throat and swollen lymph nodes during the illness.
When the fever settles, the rash appears for 1 – 2 days.
The rash consists of a mild erythematous macular rash across the arms, legs, trunk and face and is not itchy.
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Potential complications of Roseola infantum?
The main complication to be aware of is febrile convulsions due to high temperature.
Immunocompromised patients may be at risk of rare complications such as:
Myocarditis
Thrombocytopenia
Guillain-Barre syndrome.
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Roseola infantum (sixth disease) management
Children make a full recovery within a week and do not generally need to be kept off nursery if they are well enough to attend.
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What should be prescribed in ALL cases of croup?
Croup - A single dose of oral dexamethasone (0.15 mg/kg) is to be taken immediately regardless of severity
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When is the Men B vaccine given?
The Men B vaccine is given at 2, 4 and 12-13 months.
200
Patients without a spleen should be advised to ensure that they are up to date with all their vaccines, and are also recommended additional vaccines, given their susceptibility to encapsulated bacteria. There are 3 such bacteria that are particularly of concern, including?
Neisseria species - it is important that splenectomy patients receive their Men B and Men C vaccines to protect against these species of Neisseria meningitidis
Haemophilus influenzae - splenectomy patients should be encouraged to have their 6-in-1 vaccine, which protects against Haemophilus influenzae type B
Streptococcus pneumoniae - splenectomy patients are recommended to have the pneumococcal vaccine before the procedure to protect against this bacteria
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