Neurological complications of Mediterranean spotted fever

Abstract number: P723

Ammari L., Berriche A., Kilani B., Tiouiri H., Ghoubantini A., Kanoun F., Fendri C., Ben chaabane T.

Background: Mediterranean spotted fever (MSF), a systemic Rickettsia conorii, is endemic in the Mediterranean region. It thought to be a benign disaese, but in 5–10% of cases, it is responsable for severe systemic manifestations. Neurological involvement has been reported in 28% of cases.

Objective: The aim of this study is to describe demographic characteristics, clinical presentation and outcome of neurological complications of MSF.

Methods: we conducted a retrospective study of patients who developped MSF with neurological involvement between January 1992 and June 2007 and admitted in the department of infectious diseases of Rabta Hospital in Tunis. The diagnosis of MSF was based on clinical criteria and/ or positive rickettsial serology.

Results: 16 patients with neurological manifestations of MSF were included, 15 male and 1 female. The mean age is 42.7 years. 9 patients are living in rural area and 10 owned dogs. Typical clinical signs are: fever (100%), headache (43.5%) and maculopapular rash (75%), inoculation eschar (62.5%). Neurological involvement includes: 7 meningitis (44%), 5 encephalitis (31%), 3 meningoencephalitis (19%) and 1 case of facial nerve palsy (6%).

Biochemical laboratory tests revealed: normal white blood cell count in 8 cases (50%), thrombocytopenia in 7 cases (44%), hepatic cytolysis in 10 cases (62.5%). A high level of lactate dehydrogenase is noted in 10 patients (62.5%). Lumbar puncture was performed in 14 cases. Analysis of cerebrospinal fluid revealed pleocytosis with normal glucose and protein levels in 12 cases (86%). Rickettsial serology was performed for 15 patients. Antibody titers against Rickettsia conorii detected by indirect immunofluorescence are positive in only 5 patients. Cerebral CT scan is normal in 3 cases. All patients received antibiotherapy: fluoroquinolone (11 cases), doxycycline (5 cases) for a mean duration of 13 days. Mechanical ventilation was initiated for 1 patient. Clinical outcome is favourable for all patients.

Conclusion: Rickettsial infection should be considered as a cause of neurological involvement in endemic areas. Early diagnosis and appropriate treatment are mandatory to prevent fatal issue of this potential complication of Mediterranean spotted fever.