Destructive lesion of the anterior mandible: A unique presentation of leprosy

Leprosy is a chronic disease caused by infection with Mycobacterium leprae. The disease has an incubation period spanning 1-20 years with an average duration of 5 years. According to the CDC, 150-200 people in the US and 250,000 people worldwide become infected with leprosy yearly. From 2006-2015, Southeast Asia reported the highest number of new cases per year. Here we report an unusual case of intraosseous leprosy of the mandible from a 31-year-old Indian-American female. The woman presented to her oral surgeon with a destructive lesion of the anterior mandible and had associated loose teeth. She reported both prior and recent trips to India. Clinical impression at the time of surgery was a central giant cell granuloma or ameloblastoma. Histopathologic examination revealed granulomatous inflammation composed of histiocytes admixed with lymphocytes, plasma cells, and neutrophils. Discrete granulomas composed of epithelioid histiocytes and multinucleated giant cells were noted. Due to the histologic findings, GMS, PAS, and AFB Ziehl-Nielsen stains were ordered and all were reported as negative. AFB Fite stains demonstrated rare positivity. The case was diagnosed as chronic granulomatous inflammatory reaction with focal Fite stain positivity, suggestive of leprosy. While the histology is suggestive of tuberculoid leprosy, correlation with systemic evaluation and lepromin skin test were recommended. The utility of the lepromin test is to better classify the type of leprosy the patient has with positive results indicating either tuberculoid or borderline leprosy and a negative reaction supporting a diagnosis of lepromatous leprosy. Few extragnathic bony cases and intraoral cases have been reported in the English literature since 1965. This case report illustrates both an unusual and interesting case of gnathic leprosy, as well as the need to recognize that with the ease of travel, lesions that are historically seen in countries other than the United states, can be seen here.