Infectious disease Flashcards
(170 cards)
1
Q
What kind of cell walls do positive and negative bacteria have?
A
Positive - peptidoglycan call wall (stains purple)
Negative - no thick cell wall
2
Q
What is unique about atypical bacteria?
A
Cannot be stained or cultured in the normal way
3
Q
What are ribosomes?
A
Where bacterial proteins are synthesised
4
Q
What are some gram positive cocci?
A
Staphylococcus
Streptococcus
Enterococcus
5
Q
What are some gram positive rods?
A
corney Mike’s list of basic cars
Corneybacteria
Mycobacteria
Listeria
Bacillus
Nocardia
6
Q
List some gram positive anaerobes?
A
CLAP
Clostridium
Lactobacillus
Actinomyces
Propionibacterium
7
Q
What are some common gram negative bacteria?
A
Neisseria meningitis
Neisseria gonorrhoea
Haemophilia influenza
E. coli
Klebsiella
Pseudomonas aeruginosa
Moraxella catarrhalis
8
Q
Name 5 organisms which can cause atypical pneumonia?
A
legions of psittaci MCQs
Legionella pneumophila
Chlamydia psittaci
Mycoplasma pneumoniae
Chlamydydophilia pneumoniae
Q fever (coxiella burneti)
9
Q
What is Methicillin - RSA?
A
S. Aureus which has become resistant to beta-lactams e.g. penicillins, cephalosporins and carbapenems
10
Q
How can MRSA be tackled?
A
Chlorhexidine body washes (if found on nasal / groin swabs)
11
Q
What are the abx for MRSA?
A
Doxycycline
Clindamycin
Vancomycin
Teicoplanin
Linezolid
12
Q
What are Extended Spectrum Beta Lactamase bacteria ?
A
Bacteria which is resistant to beta lactam abx
Tends to be E.Coli or Klebsiella
Normally sensitive to carbapenems e.g. meropenem imipenem
13
Q
What is sepsis?
A
Immune response to infection which causes systemic inflammation and affects functioning of organs
14
Q
Which cells recognise the bacteria in sepsis?
A
Macrophages
Lymphocytes
Mast Cells
15
Q
What is released in a septic patient?
A
Cytokines
Interleukins
Tumour Necrosis Factor
to alert immune system
16
Q
What causes the vaso dilation in sepsis?
A
Nitrous oxide
17
Q
What is a result of the oedema in sepsis?
A
Space between the blood and the tissues - reducing amount of oxygen reaching the tissues
18
Q
How can septic shock be measured?
A
Systolic blood pressure less than 90 despite fluid resus
Hyperlactaemia (lactate > 4 mmol/L)
19
Q
What are some risk factors for sepsis?
A
Very old / young patients (<1 or >75)
Chronic conditions COPD/ Diabetes
Chemo, immunosuppressants, steroids
Pregnancy or peripartum
Indwelling catheters
20
Q
What scoring system is used to pick up signs of sepsis?
A
NEWS (national early warning score):
- Temp
- HR
- RR
- O2 sats
- BP
- Consciousness level
21
Q
What may be found on examination of a septic patient?
A
Potential sources of infection e.g. cellulitis, discharge from wound, cough / dysuria
Non-blanching rash
Reduced urine output
Mottled skin
Cyanosis
Arrhythmias e.g. new onset AF
Tachyopnoea = first sign
22
Q
What can a non blanching rash a sign of?
A
Meningococcal septicaemia
23
Q
When may a septic patient appear well?
A
If they’re neutropenic/immunosuppressed
24
Q
What are the investigations for sepsis?
A
FBC (neutrophils/WCC)
U&E (kidney function)
LFTs (source of infection)
CRP (inflammation)
Clotting (DIC)
Blood cultures (bacteraemia)
Blood gas (lactate, pH and glucose)
25
What additional investigations can be used to source the infection in sepsis?
**- Urine dipstick**
**- CXR**
**- CT for abscess**
**- Lumbar puncture** for meningitis or encephalitis
26
What medications may causes neutropenic sepsis?
**- Chemo**
**- Methotrexate**
**- Sulfasalazine**
**- Infliximab**
27
**Viral bronchitis** presents similarly to pneumonia, **does it requier abx**?
No
28
What are the 5 causes of atypical pneumonia?
**Lesions of psittaci MCQs**
**Legionella pneumophila**
**Chlamydia psittaci**
**Mycoplasma pneumoniae**
**Chlamydydophila pneumoniae**
**Q fever (coxiella burnetii)**
29
What would be used to treat pneumonia in the community?
Amoxicillin
30
What are some alternative medications for CAP?
Erythromycin / clarithromycin
Doxycyclin
31
How do **lower urinary tract infections present**?
**- Dysuria**
**- Suprapubic pain**
**- Frequency**
**- Urgency**
**- Incontinence**
32
How does **pyelonephritis present**?
**- Fever** (more prominent than lower UTI)
**- Vomiting**
**- Loss of appetite**
**- Back pain**
**- Haematuria**
**- Renal angle tenderness**
33
What suggests an infection on urine dipstick?
**- Nitrites** (breakdown produce of nitrates by bacteria)
**-** **Leucocytes** (if only these are present then unlikely a UTI)
34
What are some organisms causing UTIs?
**E.coli / Klebsiella pneumoniae** (gram-negative anaerobic rods)
## Footnote
**Enterococcus**
**Pseudomonas aeruginosa**
**Staphylococcus saprophyticus**
**Candida albicans**
35
What length of abx for:
**Simple UTI in women**
**Complex UTI** (immunosuppressed, abnormal anatomy)
**UTI in men / pregnant women or catheter related UTIs**?
**Simple UTI in women**: 3 days
**Complex UTI**: 5-10 days
**UTI in men?**: 7 days
36
What abx for UTI?
**Trimethoprim**
**Nitrofurantoin**
Alternatives = cefalexin, pivmecillinam, amoxicillin
37
What can be used to treat pyelonephritis in the community?
**Cefalexin**
(or co-amoxiclav, trimethoprim, ciprofloxacin)
38
How does cellulitis present?
**- Eythema**
**- Warm to touch**
**- Tense**
**- Thickened**
**- Oedematous**
**- Bullae** (fluid-filled blisters)
- Golden-yellow crust (indicates staphylococcus aureus infection)
39
What does cellulitis with a golden crust indicate?
**Staphylococcus aureus** infection
40
What are the most common causes of cellulitis
**Staphylococcus aureus**
**Group A Streptococcus** (mainly streptococcus pyogenes)
**Group C strep** (mainly streptococcus dysgalactiae)
**MRSA**
41
What medication is used for cellulitis?
**Flucloxacillin** (oral / IV)
Clarithromycin
Clindamycin
Co-amoxiclav
42
What ENT problems are commonly caused by viral infections?
**Tonsillitis, otitis media** and **rhinosinusitis**
43
What is bacterial tonisillitis commonly caused by (if not viral - which it usually is)?
Group A Streptococcus (GAS) infections, mainly **streptococcus pyogenes**
44
What are **otitis media**, **sinusitis** and **tonsillitis** not caused by **GAS** commonly caused by?
**Streptococcus pneumoniae**
(other causes = H. Influenzae, morazella catarrhalis, staphylococcus aureus)
45
What would suggest bacterial tonsilitis over viral (**Centor Criteria**)?
**Fever \> 38ºC**
**Tonsillar exudates**
**Absence of cough**
**Lymphadenopathy**
46
What is the **first line medication for bacterial tonsilitis**?
What are some alternatives?
Penicillin V (**phenoxymethylpenicillin**)
Alternatives = co-amoxiclav, clarithromycin, doxycycline
47
How does otitis media usually present, what is it usually caused by?
**Bulging tympanic membrane,** difficult to distinguish viral or bacterial
48
What are the treatment options for otitis media?
- Amoxicillin
- Macrolide
(co-amoxiclav if not responding)
49
What can sinusitis be treated with in the community (usually lasts 2-3 weeks and resolves without treatment)?
**Penicillin V** (phenoxymethylpenicillin)
**Macrolide** (if penicillin allergy)
50
Name some **possible intra-abdominal infections**?
**Acute diverticulitis**
**Cholecystitis** (with secondary infection)
**Ascending cholangitis**
**Appendicitis**
**Spontaneous bacterial peritonitis**
**Intra-abdo abscess**
51
What are some common organisms in intra-abdominal infections?
Anaerobes **(clostridium)**
## Footnote
**E. Coli**
**Klebsiella**
**Enterococcus**
**Streptococcus**
52
What does co-amoxiclav protect against?
**Gram positive, gram negative and anaerobic** (not pseudomonas or atypical pneumonia)
53
What do quinolones protect against? e.g. Ciprofloxacin and levofloxacin
**Gram positive, gram negative and atypical** (not anaerobes so usually given with metronidazole)
54
What does metronidazole protect against?
Anaerobes
55
What does gentamicin protect against?
**Gram negative** (and some staph) - bactericidal
56
What does vancomycin protect against?
**Gram positive** including MRSA (used in comb with gentamicin and metronidazole)
57
What are cephalosporins used for?
**Gram negative and gram positive** (no anaerobes and risk of **C. difficile** infection)
58
What are **tazocin** (piperacillin/tazobactam) and **meropenem** used against?
Gram positive/negative/anaerobes (not atypicals OR MRSA, tazocin not ESBLs)
59
What are some common abx regimes?
**Co-amoxiclav** alone
**Amoxicillin** plus **gentamicin** plus **metronidazole**
**Ciprofloxacin** plus **metronidazole** (**penicillin** allergy)
**Vancomycin** plus **gentamicin** plus **metronidazole** (penicillin allergy)
60
What is usually first line for **spontaneous bacterial peritonitis** (usually occurs in liver failure)?
**Tazocin**
61
How does septic arthritis usually present?
**Hot, red, swollen, painful joint**
Stiffness and reduced **ROM**
Fever, lethagy
62
What bacteria typically causes septic arthritis?
**_Staphylococcus aureus_**
**Neisseria gonorrhoea**
**Streptococcus pyogenes** (GAS)
**Haemophilus influenza**
**E. coli**
63
Diagnossi if a patient has **urinary symptoms** and swollen knee?
Septic arthritis (before reactive arthritis)
64
What are some differentials for a painful, swollen joint?
**Gout** (urate crystals = negatively birefringent of polarised light)
**Pseudogout** (calcium pyrophosphate crystals = postivelt birefringent)
**Reactive arthritis** (triggered by urethritis / gastroenteritis associated with conjunctivitis)
**Haemarthrosis**
**Septic arthritis**
65
What should the aspirate be tested for in joint swelling?
**- Gram staining**
**- Crystal microscopy**
**- Culture**
**- Abx sensitivities**
66
What are the empirical abx for septic arthritis?
**Flucloxacillin plus rifampicin**
**Vancomycin plus rifampicin** for penicillin allergy, MRSA or prosthetic joint
**Clindamycin** is alternative
67
Which patients are offered an annual flu jab?
**Aged 65**
**Young children**
**Pregnant women**
**Asthma, COPD, heart failure and diabetes** (chronic conditions)
**HCW** and **carers**
68
How does the flu present?
**- Fever**
**- Coryzal** symptoms
**- Lethargy** and fatigue
- **Anorexia** (loss of appetite)
- **Muscle** and joint aches
**-** Dry **cough**
**-** Muscle and joint **aches**
- **Sore throat**
69
How is the flu diagnosed?
**Viral nasal/throat swabs** for **PCR analysis**
70
What medication can be used for flu (usually resolves with just self care)?
**Oseltamivir** or inhaled zanamivir (needs to be started within 48 hours of onset of symptoms)
71
What are some complications of the flu?
- Otitis media, sinusitis and bronchitis
- Febrile convulsions (young children)
- Viral penumonia
- Worsening COPD and heart failure
- Encephalitis
72
What is the most common cause of gastroenteritis?
**Viral**
73
What viruses commonly cause gastroenteritis?
**Rotavirus**
**Norovirus**
**Adenovirus** (less common cause - presents with **subacute** diarrhoea)
74
How does **E.Coli** (normal intestinal bacteria) cause gastroenteritis?
Certain **strains** (contact with infected faeces, unwashed salads or water)
75
What does **E. coli 0157 produce**?
Why should abx not be used in E. coli gastroenteritis?
Produces **shiga toxin** causing **abdo cramps**, **b****loody diarrhoea**and**vomiting**- toxin also causes**haemolytic uraemic syndrome** (abx increase this risk)
76
What is the most common cause of travellers diarrhoea? How is it spread?
Campylobacter jejuni
Raw poultry, untreated water, unpasteurised milk
77
What are the signs of campylobacter infection?
After 2-5 day incubation:
- **Abdo cramps**
- **Diarrhoea with blood**
**- Vomiting**
**- Fever**
78
What are some abx for campylobacter jejuni? When might they be used?
**Azithromycin or ciprofloxacin**
Other risk factors e.g. HIV / heart failure
79
How is **Shigella transmitted**?
**Faeces** in contaminated drinking water, swimming pools and food
80
How does Shigella infection present?
Bloody diarrhoea
Abdo cramps
Fever
81
What does shigella produce?
How can **severe cases** be treated?
Shiga toxin - risk of **haemolytic uraemic syndrome**
**Azithromycin** / **ciprofloxacin**
82
What are the **features of a salmonella diarrhoea**?
**Watery diarrhoea** associated with mucus or blood
83
What is bacillus cereus?
**Gram positive rod** spread through inadequately cooked food
84
How does bacillus cereus develop?
On food which has **not been refridgerated immediately after cooking** allowing a toxin called **cereulide** to develop causing vomiting (5 hours after ingestion) and watery diarrhoea (8 hours after ingesting)
85
When does gastroenteritis caused by bacillus cereus usually resolve?
**Within 24 hours**
86
Where does the bacteria yersinia enterocolitica come from? (causing gastroenteritis)
**Gram negative bacillus** from undercooked pork causes **mestenteric lymphadenitis** (inflammation of the intestinal lymph nodes) and D&V
87
What is **Yersinia Enterococolitica**?
Who are carriers?
Who norally is affected?
How does it present?
How long can symptoms last?
**Gram negative bacillus**
Pigs (eating undercooked pork can cause infection)
Children causing watery / bloody diarrhoea fever and **lymphadenopathy** (can also cause right sided abdo pain due to **mesenteric lymphadenitis** - inflammation of intestinal lymph nodes - appendicitis impression)
Lasts **up to 3 weeks**
88
When can **staph aureus** cause gastroenteritis?
How does the infection progress?
Produce **enterotoxins** when growing in foods e.g. eggs, dairy, meat
Small intestine inflammation causing diarrhoea / vomiting / abdo cramps and fever - start within hours and settle within 12-24 hours (toxin causes enteritis)
89
What is **giardia lamblia**?
How does it present?
How is it diagnosed?
What is the treatment?
Microscopic **parasite** living in **small intestine** of mammals (may be pets, farmyard animals or humans) releasing **cysts** in stools of infected mammals (spread **faecal-oral**)
Asymptomatic or **chronic diarrhoea**
Diagnosed with **stool microscopy**
Treated with **metronidazole**
90
What is the management of gastroenteritis?
- **Good hygiene** (barrier nursing)
- Faeces tested with **microscopy, culture and sensitivities**
**-** Dioralyte if tolerating oral fluids
- Off work / school until 48 hrs after symptoms resolved
- **Antidiarrhoeal** e.g. **loperamide** and anti-emetic e.g. **metoclopramide** for MILD SYMPTOMS not for bloody diarrhoea / e.coli 0157 / shigella
Anti
91
What are some **post gastroenteritis complications**?
- Lactose intolerance
- IBS
- Reactive arthritis
- Guillain-Barre syndrome
92
What type of bacteria is **neisseria meningitis**?
What is **meningococcal septicaemia**?
What is **meningococcal meningitis**?
**Gram negative diplococcus** (commonly known as meningococcus)
Meningococcal septicaemia = mengococcal bacterial infection in the bloodstream
Meningococcal meningitis = **bacteria** is infecting the **meninges** and **CSF**
93
What does the non-blanching rash in meningococcal meningitis indicate?
DIC and **subcutaneous haemorrhages**
94
Which **bacteria** commonly causes **bacterial meningitis**?
**Children and adults** = neisseria meningitidis, streptococcus pneumoniae
**Neonate** = Group B Streptococcus
95
How does **meningitis** present?
**Fever**
**Neck stiffness**
**Vomiting**
**Headache**
**Photophobia**
**Altered consciousness**
**Seizures**
Non blanching rash (meningococcal septicaemia)
**Neonates** = non specific: hypotonia, poor feeding, lethargy, hypothermia, **bulging fontanelle**
96
When to **peform a lumbar puncture** for suspected **meningitis**?
**Under 1 month** with fever
**1-3 month** with fever and unwell
**Under 1 year** with unexplained fever and other features of serious illness
97
What is Kernig's test?
Lie patient on their back, with hip and knee flexed to 90 degrees then slowly straighten the leg and look for **spinal pain**
98
How to perform **Brudzinski's test**?
Lying patient **on back** and gently using hands to lift head and neck off bed, flexing chin to chest
**Positive** = involuntary flex **of hips and knees**
99
What are the investigations for suspected meningitis?
Lumbar puncture for CSF
Blook cultures
100
What are the **abx for meningitis**?
In **primary care** with suspected meningitis **and** non blanching rash = stat IM / IV **benzylpenicillin** (if true penicillin allergy then prioritise transfer)
In **hospital** (first send bloods for **meningococcal PCR** - tests directly for meningococcal DNA and **gives quicker result** than blood cultures)
* **\< 3 months** = **cefotaxime** plus **amoxicillin** (amx to cover listeria cibtracted during pregnancy from mother)
* **\> 3 months** = ceftriaxone
**Vancomycin** added if risk of penicillin resistant pneumococcal infection e.g. recent foreign travel / prolonged abx exposure
**Steroids** = bacterial meningitis to reduce frequency and severity of hearing loss and neurological damage
**Dexamethasone** = 4 times daily for 4 days to children over 3 months if LP suggests bacterial meningitis
**Bacterial meningitis** and **meingococcal infection** = notifiable disease so PH need informing
Ceftriaxone
Vancomycin
Steroids (reduce hearing loss)
101
What is **typically given** as **post exposure prophylaxis** for **meingococcal infection**?
**Single dose** of **ciprofloxacin** (only if within 7 days of exposure)
102
What are the common causes of viral meningitis?
What is the treatment of HSV meningitis
Herpes Simplex Virus (treated with **aciclovir**)
Enterovirus
Varicella zoster virus
(viral PCR testing)
103
Where is a needle inserted for a lumbar puncture?
**L3/L4** (after spinal cord ends at L1/L2)
104
What are CSF samples tested for?
Bacterial culture
Viral PCR
White cell count
Protein
Glucose
105
How do bacterial and viral CSF samples test?
**Bacterial** = cloudy, high protein, low glucose, high neutrophils
**Viral** = clear, normal protein, normal glucose, high lymphocytes
106
What are some complications of meningitis?
**Hearing loss**
**Seizures and epilepsy**
**Learning disability**
**Memory loss**
**Focal neurological deficits** e.g. limb weakness / spasticity
107
What kind of bacteria causes meningitis? Does it gram stain?
Mycobacterium Tuberculosis (rod shaped)
**Waxy coating** so **doesn't stain** (acid fastness)
108
Why is TB called acid-fast?
Resistant to the acids in the staining process of **gram staining**
109
What staining is used instead for bacteria?
**Zeihl-Neelsen stain** (turning bacteria **bright red** against blue background)
110
What is latent TB?
What is secondary TB?
What is disseminated TB?
**Latent TB** = immune system encapsulates sites of infection and stops progression of disease
When latent TB reactivates
**Disseminated** = immune system is unable to control disease
111
Where else does TB affect?
**Lymph nodes** (causes "cold abscesses" in neck - no inflammation, redness or pain)
Pleura
CNS
Pericardium
GI system
GU system
Bones and joints
**Cutaneous TB**
112
What are some **risk factors for TB**?
Known contact with active TB
Immigrants from high TB prevalence
Immunosuppression
Homeless
113
What type of vaccine is BCG?
**Live attenuated** intradermal injection (prior to vaccination patients are given the mantoux test and assessed for immunosuppression / HIV)
114
Who is at risk from a **live** vaccine?
Immunosuppressed and HIV
115
Who is offered a BCG vaccine?
**Neonates** born in areas of UK / other countries with high rates of TB / FH of TB
**Healthcare workers**
**Unvaccinated older children** who have close contact with TB
116
What are some signs of TB infection?
- Lethargy
- Fever
- Weight loss
- Cough with or without haemoptysis
- Lymphadenopathy
- Erythema nodosum
- Spinal pain (potts)
117
What tests can be used to see if a patient has ever had TB?
- Mantoux
- Interferon-gamma release assay
118
What can be used **if active disease is suspected**?
CXR
Cultures
119
What can a postive Mantoux test indicate?
**Previous vaccination**
**Latent**
**Active TB**
120
What does the Mantoux test involve?
Injecting some **tuberculin** (TB proteins isolated from bacteria - not live bacteria) into **intradermal** and examining for a reation after 72 hours (**induration of 5mm / more** = positive result)
121
What is involved in the interferon gamma release assay?
Mix a sample of blood with antigens from TB (if they have had previous exposure **WBC will release interferon-gamma** as part of immune response
Used after a postive mantoux to confim latent TB if no symptoms
122
What may **primary TB show on CXR**?
**Patchy consolidation, pleural effusion, hilar lymphadenopathy**
123
What may **reactivated TB** show on CXR?
**Patchy** / nodular consolidation with caviation (gas filled spaces in lungs) typically in upper zones
124
What may **disseminated miliary TB** show on **CXR**?
**Millet seeds** - uniformly distributed thoughout lung fields
125
How can cultures for TB be collected?
**3 sputum samples** (hypertonic saline to induce or bronchoscopy lavage)
**Mycobacterium blood cultures** (special bottles)
**Lymph node aspiration** / biopsy
126
When in Nucleic Acid Amplification Testing used for TB?
Results come back quicker than traditional bacterial culture so used when it would affect treatment, tested on sputum sample
127
What is the management of latent TB?
**Isoniazid and rifampicin** for **3** months
or
**Isoniazid** for **6** months
(if otherwise healthy then may not need treatment)
128
What is the drug treatment for TB?
R – **Rifampicin** for 6 months
I – **Isoniazid** for 6 months
P – **Pyrazinamide** for 2 months
E – **Ethambutol** for 2 months
129
What is co-prescribed with TB medication?
**Pyroxidine (vit B6)** as isoniazid causes peripheral neuropathy
130
What are other management concerns for TB?
Test for **HIV hep B and C**
Test **contacts**
Notify **Public Health**
Treat in **negative pressure** room (isolated)
Treatment is **different** for **extrapulmonary disease** (often involves corticosteroids)
131
What are side effects of each of the drugs?
**Rifampicin** = red/orange discolouration in urine / tears (also induces cytochrome P450 so reduces effect of drugs metabolised by P450)
**Isoniazid** = peripheral neuropathy
**Pyrazinamide** = hyperuricaemia - gout
**Ethambutol** = colour blindness and reduced visual acuity
All are hepatotoxic bar ethambutol
132
What type of virus is HIV?
RNA retrovirus - entering and destroying **CD4 T helper cells**
133
How is **HIV spread**?
Unprotected sex (anal , vaginal or oral)
Mother to child (pregnancy, birth, breastfeeding)
Sharing needles
134
What are some AIDs defining illnesses?
**Kaposi's sarcoma**
**Pneumocystis jirovecii pneumonia**
Cytomegalovirus infection
**Candidiasis**
Lymphomas
**Tuberculosis**
135
How long can **antibody** testing be negative for HIV?
**3 months** (with verbal consent documented)
136
What is the testing for HIV?
**Antibody** blood test (normal hospital test)
Testing for **p24 antigen** (can give positive result earlier in infection)
137
What PCR testing can be done for HIV?
HIV RNA virus (gives viral load)
138
What CD4 count (cells destroyed by HIV virus) is considered end stage?
**Under 200**
139
What is the **treatment for HIV**?
**Antiretroviral therapy** (irrespective of viral load CD4 count)
140
What are some classes of HAART medications (highly active anti-retrovirus therapy)?
- Protease inhibitors
- Integrase inhibitors
- Nucleoside reverse transcriptase inhibitors
141
What is given to HIV patients to prevent PCP (pneumocystis jirovecii penumonia)?
Co-trimoxazole (septrin) if CD4 \< 200
142
What are women with HIV at an increased risk of ?
Human papillomavirus and cervical cancer
143
What vaccinations should patients with HIV have?
Annual influenza
Pneumococcal
Hep A and B
Tetanus
Diptheria
Polio
**Avoid live vaccines**
144
What is the advise for sex with HIV?
Can patients safely concieve?
Can HIV mothers breastfeed?
**Condoms** for vaginal / anal sex and dams for oral sex even if both positive (if viral load undetectable then transmission is unlikely but possible)
**Sperm washing** can help to conceive safely
**C-section** should be used unless undetectable viral load
**Breastfeeding** only considered if viral load undetectable but still a risk of contracting
145
What is given as **post-exposure prophylaxis** for **HIV**?
**Truvada** (emtricitabine / tenofovir)
**Raltegravir** for 28 days
HIV test does initially but also 3 months after and should abstain from unprotected sex for 3 months after
146
How is malaria spread?
**Female anophele mosquitos** carrying **plasmodium falciparum** (from family of protozoan parasites)
147
What are the other **types** of parasites causing **malaria**?
Plasmodium falciparum
Plasmodium vivax
Plasmodium ovale
Plasmodium malariae
148
What is the pathophysiology of malaria?
**Sporozoites** (spores produced in mosquito gut as it digests infected blood) are injected into the human - travel to the liver (here can lie dormant for many years ar **P. vivax** and **P. ovale**)- mature to **merozoites** which then infect RBCs and reproduce over 48 hours - RBC ruptures every 48 hrs releasing more **merozoites** (spike in temp every 48 hours)
149
What is the incubation period of malaria?
- Fever, sweats and rigors
- Malaise
- Myalgia
- Headache
- Vomiting
- **Pallor** due to anaemia
- **Hepatosplenomegaly**
- **Jaundice**
150
How is a diagnosis of malaria made?
3 malaria blood films (sent in EDTA bottle - RBC bottle) over 3 consecutive days (due to 48 hr lifecycle)
151
What are the medication options for uncomplicated malaria?
**Riamet**
**Malarone**
**Quinine sulphate**
**Doxycycline**
152
What is the IV treatment for severe malaria?
**Artesunate**
**Quinine dihydrochloride**
153
What are some complications for **Plasmodium Falciparum** (most severe form)?
- Cerebral malaria
- Seizures
- Reduced consciousness
- AKI
- Pulmonary oedema
- DIC
- Severe haemolytic anaemia
- Multi-organ failure and death
154
What general prophylaxis is there against malaria?
- Use **mosquito sprays** (e.g. 50% DEET spray) / nets
- Use **antimalarials**
155
Name an antimalarial? When is it taken?
**Malarone** (proguanil and atovaquone) - daily 2 days before, during and 1 week after being in endemic area, most expensive (£1 per tablet)
**Mefloquine** - taken once weekly 2 weeks before, during and 4 weeks after (causes bad dreams / psychotic disorders)
**Doxycycline** - taken daily 2 days before, during and 4 weeks after being in endemic area (broad spectrum = diarrhoea and thrush, sensitivity to sun = rash / sunburn)
156
Which abx inhibit cell wall synthesis?
**_Antibiotics with a beta-lactam ring_**
* Penicillin
* Carbapenems such as meropenem
* Cephalosporins
**_Antibiotics without a beta-lactam ring_**
* Vancomycin
* Teicoplanin
157
How do **bacteria** make their own **folic acid**?
**Para-aminobenzoic acid** (PABA) is directly absorbed across cell membrane, then converted to **dihydrofolic acid** (DHFA) then **tetrahydrofolic acid** (THFA) and finally **folic acid**
158
Which abx inhibit production of folic acid?
**Sulfamethoxazole** blocks the conversion of PABA to DHFA
**Trimethoprim** blocks the conversion of DHFA to THFA
**Co-trimoxazole** is a combination of sulfamethoxazole and trimethoprim
159
What is **metronidazole** effective against?
**Anaerobes**
160
Which **abx** inhibit protein synthesis by targettting the **ribosome**?
**Macrolides** such as erythromycin, clarithromycin and azithromycin
**Clindamycin**
**Tetracyclines** such as doxycycline
**Gentamicin**
**Chloramphenicol**
161
What bacteria does **amoxicillin** cover?
**Streptococcus**
**Listeria**
**Enterococcus**
162
Which bacteria does **co-amoxiclav** cover?
Staphylococcus, haemophilus and E.Colo
163
What does **tazocin** cover?
**Pseudomonas**
164
What covers ESBLs?
Meropenem
165
What covers **MRSA**?
**Teicoplanin**
**Vancomycin**
166
What covers **atypical bacteria**?
**Clarithromycin** or **doxycycline**
167
Why are **UTIs** risky in **pregnancy**?
**Increased risk** of **pyelonephritis, premature ROM, pre-term labour**
168
How to **manage UTI** in **pregnancy**?
**7 days of abx** (even with asymptomatic bacteruria)
**Urine culture and sensitivities**
**First line:** nitrofurantoin
**Second line:** cefalexin or amoxicillin
169
When are **nitrofurantoin** / **trimethoprim** avoided in pregnancy?
170
