HUMAN AMERICAN TRYPANOSOMIASIS
HUMAN AMERICAN TRYPANOSOMIASIS ICD-10: B57.2
• Synonym. Chagas disease.
• Etiology. Trypanosoma cruzi.
• Demography. Central and South America. 6–7 million persons infected.
• Transmission. T. cruzi deposited in feces of reduviid bugs onto the skin; enters host via breaks in skin (excoriations), mucous membranes, or conjunctivae. Can also be transmitted by transfusion of blood from infected persons, by organ transplantation, and from mother to fetus.
• Dissemination. Via lymphatics and bloodstream to muscles.
CLINICAL MANIFESTATION
INOCULATION SITE CHAGOMA An indurated area of erythema and swelling, at the portal of entry, occurring 7 to 14 days after inoculation. May be accompanied by local lymphadenopathy. Parasites located within leukocytes and cells of subcutaneous tissues. These initial local signs
are followed by malaise, fever, anorexia, and edema of the face and lower extremities. ROMAÑA SIGN Unilateral painless edema of palpebrae and periocular tissues. Occurs when conjunctiva is the portal of entry. Classic finding in acute AT. Edema of face and lower extremities.
TRYPANOSOMIDES Morbilliform, urticariform, or erythematopolymorphic eruptions. HEMATOGENIC OR METASTATIC CHAGOMAS Nodule(s) caused by dissemination of infection. Hard, painful, wine-colored nodules; rarely soften or ulcerate. SYSTEMIC FINDINGS Generalized lymphadenopathy. Hepatosplenomegaly. Severe myocarditis may occur; most deaths result from heart failure. INDETERMINATE/ASYMPTOMATIC PHASE Characterized by subpatent parasitemia, detectable
antibodies to T. cruzi, absence of associated signs and symptoms. SYMPTOMATIC CHRONIC INFECTION May take several decades to develop. Symptomatic disease: Heart (rhythm disturbances, cardiomyopathy, and thromboembolism), megaesophagus, megacolon, and peripheral nervous system disease. COURSE Most infected persons remain so for life. Heart and GI involvement associated with serious morbidity and mortality.