Infectious and Tropical Diseases
Infectious and Tropical Diseases tests tuberculosis, malaria, dengue, and HIV, with emphasis on Cambodia-relevant presentation and first-line treatment. Expect questions on when to test, when to admit, and which drug is dangerous.
Core rules
- Tuberculosis: sputum Xpert MTB/RIF is first-line for suspected pulmonary TB; start standard regimen and check HIV status.
- Severe falciparum malaria: IV artesunate is first-line; do not delay for oral ACT in a patient with impaired consciousness.
- Dengue: warning signs include abdominal pain, persistent vomiting, bleeding, lethargy, and fluid accumulation; avoid NSAIDs and IM injections.
- HIV: start antiretroviral therapy in all with confirmed infection, including TB co-infection, with attention to interactions.
Worked example
A 28-year-old returns from a forested province with 4 days of fever. Platelets are 80,000/µL, NS1 antigen is positive, and there are no warning signs. This is dengue without warning signs. Give oral fluids and paracetamol, monitor hematocrit and platelets daily, and advise return if warning signs appear. Do not give ibuprofen or aspirin.
Traps
- Giving NSAIDs in dengue and causing bleeding.
- Missing malaria in a febrile patient with thrombocytopenia; do a rapid test.
- Treating severe malaria with oral artemisinin-based combination therapy.
- Forgetting HIV testing in TB and TB screening in HIV.