Central nervous system leptospirosis in the Philippines.

One hundred hospitalized patients in Manila, Philippines with aseptic meningoencephalitis were screened for leptospirosis. On the basis of a microscopic agglutination titer of 1:1,600 or greater, the diagnosis was made in five cases, yet in no instance had leptospirosis been included in the differential diagnosis on admission to the hospital. Four of the five patients first noted neurologic symptoms during the second week of illness; two patients presented with encephalitis, two with meningitis and the fifth with hemiparesis. No case was complicated by renal dysfunction or jaundice. By the time of discharge from the hospital, two patients had recovered completely and the other three had markedly improved. Our data show that leptospirosis is an important but overlooked cause of aseptic meningoencephalitis in the Philippines. This is probably also the case in other parts of the tropics where Leptospira interrogans infection remains a significant public health problem.