Neurological aspects of leptospirosis.

Since leptospirosis begins with a septicaemic stage, during which leptospirae may be isolated from the cerebrospinal fluid, the occurrence of lesions in the nervous system is not unexpected. Evidence of neurological abnormality can frequently be detected in the course of a typical attack of the disease, but it is usually insignificant compared with the involvement of other organs, and has little effect on the course or outcome of the infection. As the world-wide distribution of leptospirosis is becoming realized, however, more clinical varieties are appearing, in some of which the nervous lesions are the dominant or the only changes. These cases have not usually been jaundiced, and the infection has been caused by leptospirae other than L. icterohaeiolorrhagiae. A summary of the previous literature is followed by a description of the neurological complications arising in 64 personally studied cases in Malaya. All cases were proved by blood culture, positive serology, or both, and were due to a variety of leptospiral types, of which the commonest were L. pyrogenes, L. hebdondidis, L. canicola, L. grippotyphosa, antd L. schiiffneri.