Microbiology Flashcards
(145 cards)
Meningitis
Acute - key = Neisseria meningitidis, Strep pneumonia Hemophilia influenzae. Others - listeria, group B strep, ecoli
chronic - CT here will show changes (thickening of dura)
aseptic - enterovirus - cocksackie group B, echovirus
Mortality - 10%
Morbidity - 5, deafness most common
Encephalitis
Rabies virus, arbovirus eg West Nile
Amoeba - Naegleria fowleri
Bacteria - listeria
Trypansoma species
Prions
Toxoplasmosis
Brain abscess
Otitis media, mastoiditis etc
Staph etc
Spinal
CSF studies, how to Interpret results
Listeria meningitis management?
Viral hepatitis A B C D E
Jaundice dark urine , pale stools, pruritus
Check what antibodies/ surface markers mean
HbsAg = surface antigen most important. Positive means current infection
HbcIgM = recent infection
AntiHbc = exposure to HbV, could be past or present
AntiHbs = surface antibody = immunity due to vaccination or cleared infection
Which immunoglobulin class shows recent infection?
IgM
IgG = past/ chronic
Insert table interpreting hep B findings
Hep B medications
Nucleoside/tide analogues
Entecavir, tenofovir
If treatment history is unknown , what assay will help establish previous patients HBV status
HBV DNA viral load
Why are genotypes 1 and 2 of hep B important?
30% mortality in pregnant women
Chronic infection of hep e only happens in immunocompromised
Hep D requires infection with hep what to enter?
Hep B
Diagnosing pyrexia of unknown origin (PUO)]
History taking?
examination
investigation
definition = Fever >38.3 lasting for at least 3 weeks
1. B symptoms, localising symptoms
2. Medications - doses and initiation date
3. Contact history, pets/animal exposures
4. injecting drug use, sexual history
5. foreign travel
physical including fundoscopy (e.g roth spot endocarditis), look at spine
PET scan, Echo, brucella serology e.g patient from lebanon, HIV test for all patients, must test malaria if travel in last 2 days
if BP is 75/50 -> start Antibiotics immediately!!!!, this is sepsis and not PUO.
Infective causes of PUO
Inflammatory causes of PUO
SLE
rheumatoid arthritis
sjogrens syndromes
vasculitis syndromes
Malignant causes of PUO
lymphoma - especially non-hodgkins
leukaemia
renal cell carcinoma
Miscellaneous causes of PUO
endocrine - thyroiditis, addisons disease
TFTs screening
4 urgent causes of PUO
1. infective endocarditis
2. disseminated TB
3. central nervous system TB
4. Giant cell/ temporal arteritis
specific zoonoses
- farm/wild animals - UK or tropical
- companion animals - UK or tropical
managing patients with zoonoses
classic zoonoses
- campylobacter - chicken - diarrhoea - stool pcr for diagnosis - self resolving
- salmonella - chicken
- bartonella henslae - cats- bacilliary angiomatosis if immunosuppressed
- cats - toxoplasmosis
- brucellosis - unpasteurised milk from cattle/goat - fever, back pain, night sweats/weight loss - can present like TB. psoas abscess. psoas pus culture important
- coxiella burnetii - goat and sheep feces/milk, is aerosolised. learn presentation
- rabies - dogs, bats, cats
- rat bite fever -athralgia, fever
- hantavirus - rodents/rates - pulmonary-renal syndrome
- viral hemorrhagic fever - ebola, marburg, lassa, CCHF
opportunistic viral infections
51 year old with recent HSCT is unwell with ALT=800, what is the important test to do?
serology tests e.g EBV, hepB are not useful in immunosuppressed.
HEV PCR is useful