Infectious Disease Flashcards
How does Cholera present
Painless watery diarrhoea
severe dehydration
Diagnosis: - DARK GROUND MICROSCOPY
gram negative bacillus
comma shaped
Pathogenesis:
endotoxin cholera release
stimulates small bowel fluid secretion
What is the management of cholera
FLUIDS
CIPROFLOXACIN MAY REDUCE INPATIENT STAY
ALSO MACROLIDES AND COTRIMOXAZOLE
What causes bloody diarrhoea
Giardia lambides
Gardenella
Entaemoeba
Clostridium
What causes watery diarrhoea
Cholera
Cryptosporidium - parasitic - treat nitazoxanide
tropical sprue - metro + fluids + folic acid
post abx
coeliac
SBS
What is the treatment of cyrptosporidium diarrhoea
- Supportive management
- anti-helminth
- Praziquantel
- Nitazoxanide - blocks iron reduction in bacteria and therefore interferes with normal metabolism
How does Hookworm present
- microcytic anaemia
- eosinophilia
740million people affected greatest SS Africa
burden of 40-60 = Hb<11
treat:
Albendazole
mebendazole
praziquantel
What is Lyme disease
Caused by:
BORRELIA BURGDORFEI - Spirochete (as trypanoma palladum)
spread by:
tick bites
Erythema migrans - Bullse eye from infection site onwards Mutli-organ involvement \: fever / malaise + mylagia encephalitis cardiomyopathy AV block
What is Chagas Disease
Chagas disease is caused by Trypanosoma Cruzi
- Typically S American e.g. bolivia
- KISSING BUG - bites and excretes feces near bite
- localised histamine reaction - pruritic - host infects itself with feces
Chagas 1. oedema 2 D+V 3. mega oesophagus - PATHOGNOMIC 4. mega colon - PATHOGNOMIC 5. Cardiomyopathy
Remember as CHUGA DISEASE - BIG OESOPHAGUS BIG BOWEL
Treatment:
nitroheterocycles
What is Whipples Disease
Parasitic infection of the small bowel - jejunum
caused by T. Whippelei
GASTRO WHIPPLES
CNS WHIPPLES
OCULOMASTICATORY MYORHYTHMIA IS PATHOGNOMIC
only occurs in 20% of cases
smooth convergent divergent nystagmus of both eyes
simultaneous rhythmic dystonia of masseter and buccalis
Upgaze palsy - (IV)
+/-rhythmic movements of arms and legs
Signs
B12 and folate malabsorption
sensory neuropathy
weight loss
Symptoms: bile salt malabsorption and steatorrhoea confusion depression behavioural changes
Diagnosis: jejunal biopsy Acid alcohol fast bacillus - periodic acid Schiff stain stains infected macrophages PCR analysis
Differentials: rule out Coeliac - TTG / endomysial rule out porphyria - acute abdo pain / confusion AIP +ADP +VP + HC / PCT EPP CEP Tropical sprue (no CNS) Crohns (no CNS) malnutrition + alcohol
What is Meliodosis?
Respiratory infection caused by burkholderia psuedomallei
Endemic to Thailand / N Australia
- cavitating pulmonary abscess
- pleural effusions
- vesicular eruptions over the shins
- LFT derangement
not contagoius
transmitted from sea water and rural buildings
MORT 20-50% even with treatment
gram neg bacteria
treatment:
meropenem + cotrimoxazole
What is Typhoid fever
Caused:
Salmonella Typhi
Infected / contamined food from contaminated water
ROSE SPOTS = PATHOGNOMIC (25% present)
2-4mm raised erytheamatous maculopapular rash
presentation: abdmoinal pain lethargy + fatigue weight loss \+/- diarrhoea
Signs:
BRADYCARDIA - Faget’s sign
ROSE SPOTS - 25%
Diagnosis:
blood culture
fecal culture
Rx:
azithromycin
ceftriaxone if severe
-QUINOLONE RESISTANCE INCREASING
What is Lyme disease
Spirochete borrellia burgholderia Causes erythema migrans chronicum endocarditis arthralgia seizures and depressed GCS
Treat:
Doxy
How does Dengue Fever present?
Dengue virus
4 subtypes
Australia
fever
arthralgia
rash
headache
1st presentation = self limiting
May remit and then recur with secondary infection causing dengue haemorrhagic fever
What causes Hairy Oral Leukoplakia?
Reactivation of EBV in immunosuppressed individuals
e.g. HIV / steroids / infliximab / azathioprine
What is Katayama fever?
Schistosomiasis
high worm and egg count lead to serum sickness
i.e. IC formation and deposition
hepatosplenomegally
Treatment:
praziquantel
