Clinical

Histoplasmosis rare after solid organ transplants

Last Updated: 2009-08-17 17:00:06 -0400 (Reuters Health)

NEW YORK (Reuters Health) - Even in endemic areas, few solid organ transplant recipients develop histoplasmosis, Ohio-based researchers report in the September 1st issue of Clinical Infectious Diseases.

Dr. S. D. Mawhorter and colleagues at the Cleveland Clinic note, however, that in part because of a lack of studies, there are few specific recommendations on the ideal treatment of histoplasmosis in organ recipients.

"The Ohio and Mississippi River valleys are known to be endemic for histoplasmosis since 1945," the researchers point out. To gain more information, they reviewed data on 3436 solid organ recipients transplanted at their institution from 1997 to 2007, 38 of whom were diagnosed with post-transplantation histoplasmosis. In 29 patients, laboratory confirmation of infection was documented.

Fourteen of these patients developed proven active histoplasmosis after transplantation of a heart, lung, kidney, liver or pancreas or a combined kidney-pancreas. All 14 had disseminated disease. The median time from transplantation to diagnosis was 17 months, and the median time from onset of symptoms to diagnosis was 3 weeks.

Eleven of these patients were initially treated with amphotericin B for a median of 23.5 days, and 9 were switched to itraconazole.

Another 10 patients had evidence of histoplasmosis in their explanted organ (9 lung recipients and 1 liver recipient who also required splenectomy for splenomegaly). Four patients received donor tissue evidence of histoplasmosis, and 1 had active histoplasmosis before transplantation.

The 14 patients with evidence of infection in their explant or their donor tissue received prophylaxis, and none developed active disease. The remaining patient, who had histoplasmosis before transplantation, was given itraconazole prior to and after the procedure.

All patients were cured or are still on therapy but free of symptoms, the researchers report.

Post-transplantation histoplasmosis is rare, the investigators conclude, being limited even in their endemic region to 1 case per 1000 transplant-person years. "Prognosis is good," they add, "but requires protracted therapy."

Clin Infect Dis 2009;49:710-716.