Imported Katayama fever: clinical and biological features at presentation and during treatment.

Objectives: To investigate the characteristics of imported Katayama fever (acute schistosomiasis) as well as evolution and outcome under treatment.

Methods: Between April 2000 and September 2004, we included prospectively all patients with confirmed diagnosis of Katayama fever. Follow-up was maintained at least until 6 months after symptoms resolved. Praziquantel (PZQ) was given as soon as the diagnosis was probable, most of the time with steroids.

Results: Twenty-three patients were diagnosed with Katayama fever by Schistosoma egg detection and/or by seroconversion. Clinical features were non-specific, with mainly respiratory and/or gastrointestinal symptoms. Diagnosis was confirmed at presentation in 17/23 (74%) patients, of whom 15 by serology. Immediate clinical exacerbation occurred in five of nine patients not given steroids concomitantly with PZQ. After initial resolution, fever recurred in five (22%) patients. When compiling initial and recurrent episodes (n=28), respiratory symptoms tended to occur at an earlier stage after exposure, while abdominal complaints were more frequent later. All patients were completely cured, sometimes after repeated treatments.

Conclusions: Clinical presentation of Katayama fever is non-specific and involves respiratory and abdominal symptoms. Recurrence of fever is not unusual despite anti-helminthic treatment. Optimal therapeutic strategy remains to be defined to prevent recurrence.