Acta Dermato-Venereologica 99-13CompleteContent | Page 36

1315 Multifocal Cutaneous Infections Caused by Mycobacterium szulgai without Pulmonary Involvement Wei ZHANG # , Siyue KAN # , Haiqin JIANG, Hongsheng WANG*, Xiaofang LI* and Jianfang SUN Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical College, 12, Jiangwangmiao Street, Nanjing 210042, Jiangsu Province, China. *E-mails: [email protected], [email protected] # These authors contributed equally to this paper. Accepted Oct 16, 2019; E-published Oct 17, 2019 Pulmonary infection with Mycobacterium szulgai, which resembles tuberculosis, is the most common clinical presentation of this pathogen, especially in immuno- compromised individuals. Extrapulmonary infections with M. szulgai are very rare. We report here a case of extrapulmonary multifocal cutaneous infections with M. szulgai and review previous cases. CASE REPORT A 36-year-old man with no history of tuberculosis or immuno­ suppression treatment presented with multifocal asymptomatic erythematous nodules and plaques with exudate on his left hand, right ear and left elbow for 20 years (Fig. 1). He had damaged his left little finger 20 years previously in an accident with a sickle. His finger had subsequently been amputated at the local hospital due to repeated inflammation with  no  response  to  antibiotics. One year after the amputation, the same lesions were noted on the same site and spread to his right ear and left elbow. He was SHORT COMMUNICATION A B a heavy smoker (approximately 1 pack per day). He had no dia- betes, hypertension or other comorbidities, and no family history of tuberculosis or other infections. Routine laboratory tests were normal and the patient was negative for HIV and anti-extractable nuclear antigen (anti-ENA) autoantibodies. Chest X-ray and computed tomography (CT) did not reveal any abnormal lesions. Three mycological cultures were performed with no positive results. Histopathology of a biopsied specimen from 3 sites of involvement revealed the same pathological reaction pattern; pseudoepitheliomatous hyperplasia with intraepithelial abscesses, and suppurative granuloma formations were present with periphe- ral mixed infiltration of lymphocytes, neutrophils, eosinophils, plasmacytes and multinuclear giant cells (Fig. 2). Neutrophil abscesses were focally formed. Löwenstein-Jensen medium was used for mycobacterial culture. Slow growth of yellow colonies occurred after 3–4 weeks of culture at 37°C. Acid-fast bacilli were positive in the tissue fluid of skin lesion by Ziehl-Neelsen staining. The characteristics of the colonies were consistent with M. szulgai strain. Sequence analysis of hsp65 genes showed 100% similarity with M. szulgai strain. Gene sequences were analysed using BLAST V2.0 software (available from: http://www.ncbi. nlm.nih.gov/BLAST/). Gene sequencing results indicated that the strain was most likely to be M. szulgai and a diagnosis of M. szulgai infection was therefore made. After diagnosis, the patient was treated empirically with clarithromycin (500 mg/day), ethambutol (750 mg/day) and rifampicin (450 mg/day) for 6 months. At 4-month follow-up, the patient’s skin lesions had greatly improved. Complete resolution was achieved after 6 months of antimycobacterial therapy. The patient’s C skin lesions recovered completely without relapse during a 36-month follow-up. DISCUSSION D G E H F I Fig. 1. Clinical manifestations before and after treatment. Before treatment: erythematous plaque on (A) the dorsum of the left hand, (B) the left elbow, and (C) the right ear. After 3 months of treatment: lesions on: (D) the dorsum of the left hand, (E) the left elbow, and (F) the right ear. After 3 months of treatment: (G) scar and hypopigmentation on the dorsum of the left hand, (H) scar on the left elbow, and (I) scar on the right ear. This is an open access article under the CC BY-NC license. www.medicaljournals.se/acta Journal Compilation © 2019 Acta Dermato-Venereologica. M. szulgai is an atypical mycobac- terium that was first discovered in 1972 (1). M. szulgai  infection is very rare in humans, accounting for less than 0.5% of all non-tu- berculous mycobacteria infections (2, 3). Pulmonary infection with M. szulgai, which resembles tuberculo- sis, is the most common clinically involved site, while extrapulmo- nary and multifocal infections are very rare. Only 11 cases of cuta- neous infection due to M. szulgai have been reported in the literature in English, including subcutaneous doi: 10.2340/00015555-3352 Acta Derm Venereol 2019; 99: 1315–1316