Facial Mycobacterium abscessus infection in a patient misdiagnosed as dermatomyositis: A rare case report

Dear Editor, A 65-year-old female developed persistent erythema around the eyes over 2.5 years, without any accompanying symptoms. Her medical history included stage 5 chronic kidney disease, renal anemia, and hypertension. She had been receiving hemodialysis for 14 years, and her rash worsened on dialysis days and after sun exposure. Despite treatment with topical halometasone, tacrolimus, and other medications at multiple hospitals in Guangzhou, the rash did not improve. She was previously diagnosed with dermatomyositis at another hospital 10 months ago but without muscle weakness or abnormal myocardial enzymes. Treatment with prednisone 20 mg/day, azathioprine 100 mg/day, and hydroxychloroquine 0.2 g/day did not significantly improve the rash. Four weeks ago, the rash suddenly worsened without an obvious cause, with diffuse, pruritic erythema and blisters appearing on her face, accompanied by a fever of up to 38°C. Topical aureomycin and tacrolimus ointments were ineffective. Physical examination revealed diffuse, edematous erythema, papules, blisters, necrosis, and crusts on the face, with significant eyelid swelling [Figure 1a]. Relevant laboratory findings included an elevated serum anti-nuclear antibody titer of 1:320, with normal extractable nuclear antigen, complement, anti-neutrophil cytoplasmic antibody, and myocardial enzymes. Notably, urea, creatinine, uric acid, potassium, chlorine, and phosphorus levels were elevated or outside the reference range, indicative of her underlying renal dysfunction. Direct immunofluorescence was negative for immunoglobulin (Ig) A, IgG, IgM, C3, and C1q. Skin biopsy showed obvious elastotic degeneration and superficial and deep lymphocytic infiltration in the dermis, but no interface dermatitis [Figure 1d-f]. The acid-fast staining was negative. Tissue fungal culture was negative. The test for tuberculosis antigen MPB64 was negative. Tissue culture was positive for Mycobacterium. The strain was further identified as Mycobacterium abscessus [Figure 1c].Figure 1: (a) Diffuse edematous erythema, papules, blisters, necrosis, and scabs on the face. Eyelids swelled obviously. (b) The lesions completely subsided at follow-up of 6 months. (c) The picture shows the result of agar culture: Cheese-like opaque colonies with round, neat edges can be seen. (d) Under low power of microscopy, granuloma was seen in the dermis. There were proliferating capillaries associated with perivascular infiltration of inflammatory cells (H and E, ×100). (e and f) Under high power view, cluster of epithelioid cells was seen admixed with lymphocytes, eosinophils, and neutrophils. No multinuclear cell was seen (H and E, ×400).Based on the histological and microbiological findings, the patient was diagnosed with facial M. abscessus infection. She was prescribed oral clarithromycin 250 mg once daily, ethambutol 250 mg thrice daily, and rifampicin 450 mg once daily, and the rash gradually improved. However, rifampicin was discontinued due to severe gastrointestinal adverse effects and elevated aminotransferase levels. The rash significantly subsided after a course of treatment for 6 months, and the lesions completely resolved without scarring or pigmentation at follow-up of 6 months [Figure 1b]. M. abscessus is a rapidly growing nontuberculous Mycobacterium that commonly causes skin and soft-tissue infections, particularly in immunocompromised individuals with chronic diseases such as AIDS, cancer, diabetes, and anemia.[1] It was first isolated from a patient’s knee abscess in 1953 by Moore and Frerichs[2] Cutaneous M. abscessus infections can manifest with diverse clinical features, including erythema, papules, nodules, abscesses, ulcers, sinuses, and cellulitis. Rare presentations such as nodular erythema and alopecia have also been reported.[3] The diffuse facial lesions in our patient are an unusual presentation that has not been commonly described. The lesions and pathological results of this disease are nonspecific. The diagnosis depends on the bacterial isolation and identification of the diseased tissue. At present, the gold standard for strain identification is homologous gene sequence analysis. 16S rRNA gene is the most commonly used target for Mycobacterium identification, which can identify M. abscessus. Due to the high drug resistance of M. abscessus, treatment is challenging. The latest ATS/ERS/ESCMID/IDSA clinical practice guidelines (2020) recommend an initial phase of 1–2 parenteral drugs[4] (e.g., amikacin, imipenem, cefoxitin, and tigecycline) and 2 oral agents (e.g., azithromycin, clofazimine, and linezolid) for macrolide-susceptible strains, or 2–3 parenteral and oral drugs for macrolide-resistant organisms, along with inhaled amikacin. To date, 32 reported cases of facial M. abscessus infections have been documented, predominantly affecting women aged 31–40 years [Supplementary Table 1].[5-8] Symptoms’ duration varied from 7 to 90 days, with the most common presentation being facial nodules and abscesses. A significant number of these cases were linked to cosmetic procedures, particularly fat grafting (about 66%). Our patient presented a unique case, with no history of prior facial medical interventions or trauma, which complicated the diagnosis. The initial rash appeared around the eyes and was initially misdiagnosed as dermatomyositis. Despite treatment, the condition did not improve and worsened due to the delay, underscoring the need for clinicians to consider rare presentations of nontuberculous mycobacterial (NTM) infections.Supplementary Table 1: Characteristics of the reported cases of facial Mycobacterium abscessus infectionThe misdiagnosis of dermatomyositis and the ineffective treatment with immunosuppressive drugs illustrate the diagnostic challenges faced with rare NTM presentations. The patient’s eventual recovery following a customized antibiotic regimen emphasizes the critical importance of accurate diagnosis and the necessity of long-term antibiotic therapy in managing M. abscessus infections. Data availability statement The datasets generated during and/or analyzed during the current study are publicly available. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent form. In the form, the patient has given her consent for her images and other clinical information to be reported in the journal. The patient understands that her name and initials will not be published and due efforts will be made to conceal her identity, but anonymity cannot be guaranteed. Financial support and sponsorship This work was funded by Shenzhen Municipal Stable Support Plan for Higher Education Institutions (approval number: 20231122162117001). Conflicts of interest There are no conflicts of interest.