Hantavirus pulmonary syndrome in Brasilia periphery: a diagnostic challenge

BACKGROUND: Hantavirus pulmonary syndrome (HPS) is an emerging rodent-borne disease in the American continent, characterized by acute respiratory distress and a high case-fatality ratio. The present work describes a case of HPS, with favorable outcome, whose initial features were mistaken for leptospirosis or other less severe acute infections. METHODOLOGY: The case of a 32-year-old male with an uneventful course of HPS is reported. He was inadvertently infected at work by exposure to a rodent-contaminated environment in Brasília, Federal District vicinity, during May 2008. RESULTS AND CONCLUSIONS: Fever, headache and myalgia after exposure to a rodent-contaminated environment raised clinical suspicion. Non-cardiac pulmonary edema, hydrothorax, neutrophilia with band forms 26%, high hematocrit, thrombocytopenia, and elevated liver enzymes were observed. Leptospirosis and dengue were the main differential diagnoses because both pathogens are endemic in the area. Hantavirus IgM antibody-capture ELISA was positive, while tests for dengue, leptospirosis and yellow fever were negative. The prognosis for HPS is ominous and misdiagnoses may increase mortality. Better chances of survival depend on prompt intensive care support. Reports of moderate or less typical cases can raise the suspicion index among primary care and hospital-based physicians about this uncommon but severe condition that often affects previously healthy young individuals from developing countries, and subjects who interact with rodent-infested environments in North America. High awareness of HPS allowed successful management of the patient, even before establishing the diagnosis, by serological tests at the reference laboratory of the Ministry of Health. Clinical suspicion favored warning local health authorities about a new case of HPS.