ID: tropical diseases Flashcards
headache, fever, seizures and confusion. Parkinsonian features indicate basal ganglia involvement. It can also present with acute flaccid paralysis.
Japanese encephalitis
Retro-orbital headache, fever, facial flushing, rash, thrombocytopenia
How to test?
dengue
diagnostic tests
serology
nucleic acid amplification tests for viral RNA
NS1 antigen test
Rx supportive
Name viral haemorrhagic fevers
dengue fever,
Lassa fever,
Ebola
Yellow fever
Uncomplicated falciparum malaria
artemisinin-based combination therapies:
-artemether + lumefantrine,
artesunate +amodiaquine,
artesunate +mefloquine,
artesunate +sulfadoxine-pyrimethamine,
dihydroartemisinin plus piperaquine
Rx Severe falciparum malaria
intravenous artesunate i
If parasite count > 10% then exchange transfusion
massive splenomegaly. hepatomegaly
Graying of skin
Pancytopenia
Visceral leishmaniasis (kala-azar)
Name and describe 3 leishmaniasis
Cutaneous leishmaniasis (Leishmania tropica/ Leishmania Mexicana)- * crusted ulcer at site of bite no rx
Mucocutaneous leishmaniasis
Leishmania braziliensis- involves mucus membrane
Visceral leishmaniasis (kala-azar) Leishmania donovani- massive splenomegaly. hepatomegaly graying of skin
What causes Leishmaniasis
Leishmaniasis
intracellular protozoa Leishmania,
spread by sand flies
What causes Leptospirosis & How is it spreads
spirochaete Leptospira interrogans (serogroup L. icterohaemorrhagiae),
classically being spread by contact with infected rat urine
Leptospirosis SX, IX & Rx
- Early phase is due to bacteraemia & lasts around a week
flu-like symptoms
+ subconjunctival suffusion (redness)/haemorrhage - 2nd immune phase (Weil’s disease)
o AKI (seen in 50% of patients)
o hepatitis: jaundice, hepatomegaly
o aseptic meningitis
Ix: * serology: antibodies to Leptospira develop after about 7 days
RX:
high-dose benzylpenicillin or doxycycline
American trypanosomiasis, or Chagas’ disease,
sx in acute phase
95% asymptomatic
1. chagoma (an erythematous nodule at site of infection) an
2. periorbital oedema are sometimes seen. Romana sign
Chronic phase of American trypanosomiasis, or Chagas’ disease,
Chronic :
1. myocarditis may lead to dilated cardiomyopathy (with apical atophy) and arrhythmias
2. megaoesophagus and megacolon causing dysphagia and constipation
Rx trypanosomiasis, or Chagas’ disease,
Rx
* benznidazole or nifurtimox
* chronic disease management involves treating the complications e.g., heart failure
African trypanosomiasis, or sleeping sickness vector sx and Rx
- Trypanosoma chancre - painless subcutaneous nodule at site of infection
- intermittent fever
- enlargement of posterior cervical lymph nodes
- later: CNS involvement e.g. somnolence, headaches, mood changes, meningoencephalitis
Rx: - early disease: IV pentamidine or suramin
- later disease or central nervous system involvement: IV melarsoprol
What causes rocky mountain spotted fever: sX IX Rx
Rickettsia ricketsii
Rash starts on the peripheries (wrist, ankles) –>centrally.
It is initially maculopapular before becoming vasculitic
Ix:Weil-Felix reaction is positive
Rx: tetracyclines
