Suspected leptospiral meningitis in adults: report of four cases and review of the literature

Leptospirosis is a widespread zoonotic disease characterised by headache and fever. These symptoms are often suggestive of meningitis, but only a proportion of patients have leptospiral meningitis. We report episodes of leptospiral meningitis in patients admitted to a tertiary referral centre in the Netherlands, in whom lumbar puncture was performed, and conducted a literature search of adult cases of leptospiral meningitis to describe clinical characteristics and outcome. Between 2011 and 2014, 19 patients with leptospirosis were identified. Seven underwent a lumbar puncture for suspected meningitis (37%), of which six had been in contact with fresh water in a tropical area. Four patients with suspected meningitis (57%) had cerebrospinal fluid pleocytosis indicative of leptospiral meningitis and presented with headache, fever and neck stiffness. In a review of the literature we identified 366 patients with leptospiral meningitis with a median age of 33 years (range 17-77). Risk factors for leptospirosis were identified in 32 of 33 patients. Typical cerebrospinal fluid abnormalities consisted of a mildly elevated leukocyte count (median 206 leukocytes/mm3, range 6-2072) with a lymphocytic predominance (median 95%). Outcome was generally favourable, with a mortality rate of 3% and neurological sequelae in 5% of the survivors. Leptospirosis in the Netherlands has a low incidence. In the case of suspected meningitis and a history of visiting tropical areas or direct or indirect contact with animal urine, leptospiral meningitis should be considered. Cerebrospinal fluid examination is vital for the differential diagnosis of leptospirosis. Outcome is generally favourable in patients with leptospiral meningitis treated with antibiotics.