A 52-year-old man from Western Province, Saudi Arabia was referred for a possible right-hand palm tumor. He had a history of uncontrolled diabetes mellitus and a 5-year history of a recurrent painless mass involving his right middle finger, extending proximally to the palm, progressing in size over 6 months prior to presentation. The mass started as a tiny painless nodule that subsequently enlarged, thereby restricting hand motion. A trial surgical excision 2 years prior to presentation was successful in removing the mass, which did not recur for almost a year. However, the mass subsequently enlarged and began producing a whitish discharge.
Multiple sinuses were noted (Fig. 2A). Initial laboratory examinations, including a CBC and chemistry panel, revealed normal results. HIV test results were negative.
Plain radiography and magnetic resonance imaging (MRI) of the right hand showed multi-lobulated enhancing soft tissue conglomerated masses at the base of the middle finger, extending along its volar proximal aspect, circumferentially surrounding the finger and its tendons. No signs of tenosynovitis or osteomyelitis were observed (Fig. 2B).
The patient underwent an incisional biopsy and mass debridement. Tissue Gram staining and culture showed negative findings. AFB smear and polymerase chain reaction (PCR) findings were also negative for tuberculosis. Macroscopic examination of the sample revealed a mass approximately 2.0 x 1.5 cm in size and pinkish tan in color. Microscopic examination revealed skin with underlying tissue showing heavy infiltration by actinomycetes (positive results for the gomori methanamine silver [GMS] and periodic acid-Schiff [PAS] tests) that caused a severe inflammatory reaction and tissue destruction (Fig. 3C and D).
The patient was treated with oral amoxicillin/clavulanic acid (1 g) every 12 h and then discharged home. During the follow-up 2 months later, a whitish discharge was observed. He was referred for further debridement. After six months of treatment, he showed marked improvement.