Atypical mycobacteriosis means the infection of nontuberuculous mycobacteria, and it is a rare disease in the head and neck regions. Since the clinical and histopathologic features of this disease are similar to those of tuberuculosis, a bacterial examination to identify the causative organism is essential. A case of atypical mycobacteriosis which appeared in the left buccal area and was diagnosed by bacterial isolation is reported.
An 8-year-old boy visited our hospital for evaluation of the left buccal and submandibular swelling. On examination, no dental caries was found in the left mandibular teeth and hematologic and radiologic examinations revealed leukocytosis and the presence of a radiolucent area at the apex of CD. The swelling was thought to be related to the abscessed mandibular molars, and extraction of CD was performed. However, there was no decrease in the swelling. One month after tooth extraction, intracutaneous reaction with PPD revealed a positive conversion, and biopsy materials were taken from the buccal and submandibular lesions. Sections of the materials showed features of a granulomatous inflammation of lymphnodes. Scattered epitheloid cells and giant cells of Langerhans type as well as lymphocytic infiltration suggestive of tuberuculosis were seen. Mycobacterium fortuitum clasified into Group IV of nontuberuculous mycobacteria was isolated from the pus obtained from the buccal lesion.
Based on these findings, a diagnosis of atypical mycobacteriosis was established. The patient was treated with antituberuculous agents including rifampicin and isoniazid. In spite of this treatment, another subcutaneous lesin appeared in the left arm and was surgically excised. Drug the rapy was continued for additional six months. The patient has remained free of disease for about two years after the second surgical treatment.