INFECTIOUS DISEASE 1 Flashcards
(54 cards)
Which 2 clinical parameters may indicate septic shock rather than sepsis alone, and what treatment does it require:
Vasopressor requirement for MAP to be maintained >65
Serum lactate of >2 in absence of hypovolaemia
Requires aggressive HDU/ITU fluid resuscitation and noradrenaline, which increases SVR and MAP/
Patients with ‘red flag’ symptoms in sepsis are at high risk of severe illness and mortality. What are these red flags?
Responding only to V and P
Acute confusion
Mottled, cyanotic
No urine in last 18 hrs
SBP <90
Heart rate >130
RR >25
Recent chemo
What does a SOFA score of 2 reflect?
(Sequential Sepsis-Related Organ Failure Assessment score)
Overall mortality risk of 10% in the general hospital population wit suspected infection
qSOFA score criteria?
RR >22
Altered mental status
SBP <100
Used to predict mortality NOT diagnosis
Hyposplenism due to e.g. splenectomy increases the risk of sepsis, especially from encapsulated organisms. Vaccination and abx prophylaxis are crucial for prevention. Give the recommended vaccinations and abx prophylaxis:
If possible, most should be given 2 weeks prior e.g. if elective splenectomy. If can’t, then as soon as possible afterwards.
Pneum, and PCV13 at 8 weeks later + 5 yearly booster
HiB + MenC
MenB, ACWY 2 weeks after
Prophylaxis is penicillin V , for at least 2 years
Seek medical attention for ANY febrile illness
When does neutropenic sepsis most commonly occur, and how is it diagnosed, + most common organisms:
7-14 days post chemo
Neutrophils <0.5 , fever >38 or other sepsis clinical signs
CONS g+ve most common e.g. Staph epidermis.
?indwelling lines
Treatment of neutropenic sepsis:
Pip/taz first line, do not wait for blood results.
If not improving after 48 hours give meropenem or vancomycin.
If not responding after 4-6 days, do fungal investigations.
Consider G-CSF
If at high risk of neutropenic sepsis, consider fluoroquinolone prophylaxis
Malaria is caused by Plasmodium protozoan parasites; which is the most common type, and how is it spread?
Falciparum
Female Anopheles mosquito
5 types of malaria:
Falciparum
Vivax
Ovale
Malariae
Knowlesi
How is malaria spread / reproduced / life cycle:
Female mosquito sucks up blood from infected person.
Parasite reproduces in the gut producing SPOROZOITES.
Mosquito bites and uninfected person, the sporozoites travel to the liver.
They mature in the liver to merozoites and enter circulation and infect rbcs.
RBC rupture = haemolytic anaemia and further spread.
Describe difference in fever spikes between the types of malaria:
Vivax and ovale rupture every 48 hours.
Falciparum ruptures more irregularly ~ 48 hours.
Malariae ruptures every 72 hours.
Vivax and ovale can lie dormant
Many of the symptoms of malaria are non-specific, including extremely high fever, fatigue, myalgia, headache, n&v. What signs may you see on examination, and what is the normal incubation period (if not dormant):
Hepatosplenomegaly
Pallor due to anaemia
Jaundice due to bilirubin release from rbc rupture
Inc = 1-4 weeks
Diagnosis of malaria:
Malaria blood film sent, in EDTA bottle.
Will show parasites and concentration in % and type.
What is required to exclude a diagnosis of malaria and why?
3 negative blood films taken on 3 consecutive days, due to the cyclical rupturing.
Management of uncomplicated falciparum malaria:
ACTs first line:
Artemether and lumefantrine oral
*Increasing rates of chloroquine resistance in Asia and Africa
Management of severe falciparum malaria:
> 2% parasites
IV artesunate (side effect is haemolysis)
If >10% consider n exchange transfusion
Severity; shock may indicate an overlying bacterial infection as malaria does not often cause haemodynamic collapse
Complications of P.falciparum malaria:
Cerebral malaria
Acute renal failure (dark red/black urine)
ARDS
Hypoglycaemia
DIC
Features of severe malaria:
Schizonts on blood film
>2% parasitaemia
Hypoglycaemia
Acidosis
Temp >39
Severe anaemia
+ other complications
Most common cause of non-falciparum malaria:
Vivax
Where are vivax, ovale and knowlesi most commonly found?
Vivax: central america and indian subcontinent
Ovale: Africa
Knowelsi = south east asia
Which two types have a hyponozoite / latent phase (malaria):
Vivax
Ovale
Patients diagnosed with ovale or vivax malaria should be given what following acute treatment, and why?
Primaquine, to destroy liver hypnozoites and prevent relapse
Discuss malaria treatment in pregnancy:
IV artesunate first line in severe, in all trimesters.
ACTs are avoided in pregnancy ideally.
Uncomplicated malaria;
1st trimester: Quinine and Clindamycin
2/3rd: ACT
Non-falciparum; chloroquine (but cannot give primaquine, as this can cause neonatal haemolysis), deferred until post partum.
Antimalarial medications are not 100% effective and come with side effects. Give the options and state some of the side effects
Proguanil / ato (Malaron) = less side effects. Take 2 days prior and 7 days after travel.
Doxycycline - diarrhoea and thrush + skin sensitivity to light. 2 days prior and 4 weeks after.
Mefloquine has psychiatric side effects/ Taken weekly, 2 weeks before and 4 weeks after.
