Confirming the diagnosis of invasive fungal sinusitis

Acute invasive fungal rhinosinus- itis occurs predominantly in immunocompromised patients, such as those with neutropenia and transplant recipients. The diagnosis requires biopsy, but permanent section can be time-consuming and result in a delay in treatment. Ghadiali and colleagues conducted a study to evaluate the accuracy of frozen-section biopsy in this setting.

They retrospectively studied 20 patients (aged 8 to 76 years) who had acute invasive fungal rhino- sinusitis; 11 had invasive mucormycosis and 9 had invasive aspergillosis. The patients' underlying conditions included diabetes mellitus, solid organ transplantation, HIV/ AIDS, and leukemia.

The diagnosis of invasive fungalinfection was confirmed by histopathology on permanent section; frozen sections were performed as well. Using permanent section as the diagnostic gold standard, the overall sensitivity for frozen section was 0.84, specificity was 1, negative predictive value was 0.72, and positive predictive value was 1. Diagnostic accuracy was not significantly different between the mucormycosis and aspergillosis groups. In contrast, cultures were positive in only 11 of 20 cases; the overall sensitivity for cultures was 0.55.

The authors conclude that frozen-section biopsy is a valuable way to provide an early diagnosis of acute fungal rhinosinusitis. They say that clinicians should consider this diagnosis in immunocompromised patients who have sinus complaints even if a sinus CT scan does not show any evidence of invasive disease.