MRI of head and neck paracoccidioidomycosis

Paracoccidioidomycosis, caused by the dimorphic fungus Paracoccidioides bra siliensis, is the most important systemic mycosis in Latin America. Importe d cases have been reported in North America, Asia and Europe, in individual s who lived in endemic areas, sometimes many years before the development o f clinical manifestations. The disease causes cutaneous and/or respiratory tract mucosal lesions as well as lymph node enlargement. Involvement of the oropharynx and/or the larynx, either alone or in association with pulmonar y involvement, is one of the commonest clinical presentations. On MRI, the major features are mucosal lesions, usually hypointense on T-1 weighted ima ges and hyperintense on T-2 weighted or fat suppressed images, affecting th e oral cavity, oropharynx and larynx, with head and neck lymph node enlarge ment. Differential diagnosis includes other granulomatous infectious diseas es, especially tuberculosis, and cancers such as squamous cell carcinoma an d lymphomas.