Synopsis
Recognise leishmaniasis forms, distinguish African sleeping sickness from Chagas disease, secure reference confirmation and start stage-specific specialist care.
- Leishmania is transmitted by infected sandflies and presents as cutaneous ulcers, destructive mucosal disease or visceral infection affecting spleen, liver and marrow.
- Visceral leishmaniasis causes prolonged irregular fever, weight loss, massive splenomegaly, cytopenias and hypergammaglobulinaemia; prompt complete treatment is essential.
- First-line confirmation of cutaneous or mucosal disease uses lesion scraping, aspirate or biopsy for microscopy, culture and PCR; serology is usually unhelpful for isolated skin disease.
- For visceral disease, obtain specialist-directed marrow or other tissue microscopy, culture and PCR with serology; tissue parasite demonstration is definitive but sampling risk and sensitivity vary.
- African trypanosomiasis follows tsetse exposure: T. b. rhodesiense is often acute in eastern or southern Africa, whereas T. b. gambiense progresses more slowly in western or central Africa.
- Demonstrate African trypanosomes in blood, chancre or lymph-node material, then stage central nervous system involvement using the current WHO specialist algorithm because treatment depends on form and stage.
- Chagas disease is caused by T. cruzi, transmitted by triatomine faeces, congenitally, through contaminated food, blood, organs or laboratory exposure.
- Acute Chagas may cause fever, a chagoma or unilateral Romaña eyelid swelling; chronic disease causes cardiomyopathy, arrhythmia, stroke, megaoesophagus or megacolon decades later.
- Confirm chronic Chagas with two different serological assays; use PCR or microscopy for acute, congenital or reactivated infection and stage every confirmed case for cardiac and digestive damage.
- Treatment is never selected by syndrome name alone: Leishmania species and geography, African trypanosome form and CNS stage, or Chagas phase, pregnancy and organ function determine the regimen.
Key red flags
Prolonged fever, weight loss, marked splenomegaly and pancytopenia after endemic residence can be untreated visceral leishmaniasis, which is usually fatal without therapy.
Confusion, abnormal sleep-wake cycle, tremor, ataxia, psychiatric change or coma after sub-Saharan exposure may indicate central nervous system human African trypanosomiasis.
Acute fever after safari travel in eastern or southern Africa with a painful tsetse chancre can represent rapidly progressive rhodesiense sleeping sickness.
Mucosal ulceration, epistaxis, nasal obstruction or destructive oral disease months or years after a Latin American skin lesion needs urgent leishmania species assessment.
Syncope, palpitations, conduction block, ventricular arrhythmia or heart failure in someone from continental Latin America may be chronic Chagas cardiomyopathy.
Immunosuppression increases visceral leishmania relapse and Chagas reactivation risk; negative antibody tests are less reassuring in these hosts.
Progressive nasal blockage, epistaxis, septal destruction, oral ulceration or voice change can follow a remote New World skin lesion.
Persistent fever, cachexia, darkened skin, very large spleen, hepatomegaly, pancytopenia and polyclonal hypergammaglobulinaemia form the classic kala-azar pattern.
Investigation priorities
Define epidemiological plausibility, competing emergencies and organ injury before rare-pathogen confirmation.
Management branches
A compatible skin, mucosal or visceral syndrome follows sandfly exposure in an endemic region.
- Classify cutaneous, mucosal or visceral disease and record lesion number, size, site, duration, mucosal symptoms, immune status and complete geography.
- Send appropriate lesion or tissue material for microscopy, culture and PCR through a tropical laboratory; add serology for visceral but not as a skin-disease rule-out.
- Admit and treat visceral disease promptly while supporting anaemia, neutropenic sepsis, bleeding and malnutrition; avoid traumatic splenic procedures outside expert hands.
- Let species, geography, lesion risk, immune status and organ involvement determine observation, local therapy or systemic antileishmanial treatment.