Sakatoku Yayoi, Okada Yoshito, Takahashi Yohei
Department of Surgery, Handa City Hospital, 2-29 Toyo-Cho, Handa-City, Aichi, 475-8599, Japan.
Department of Diagnostic Pathology, Handa City Hospital, 2-29 Toyo-Cho, Handa-City, Aichi, 475-8599, Japan.
Surg Case Rep. 2023 Jul 5;9(1):125. doi: 10.1186/s40792-023-01706-8.
Mycobacterium chelonae, a nontuberculous mycobacterium, commonly causes skin, soft tissue, eye, pulmonary, catheter-related, and post-surgical infections in patients with immunosuppression or trauma. M. chelonae breast infections are rare, and most cases occur following cosmetic surgery. Here, we report the first case of spontaneous breast abscess due to M. chelonae.
A 22-year-old Japanese woman presented at our hospital with swelling and pain in the right breast for the past 2 weeks without any fever. She had a 19-month-old child and stopped breastfeeding 1 month after giving birth. The patient had no history of trauma or breast surgeries, no family history of breast cancer, and was not immunocompromised. Breast ultrasonography revealed a heterogeneous hypoechoic lesion with multiple fluid-filled areas suspected to be abscesses. Dynamic contrast-enhanced magnetic resonance imaging revealed a 64 × 58 × 62 mm, ill-defined, high-signal-intensity lesion with multiple ring enhancements in the upper half of the right breast. The first diagnosis was inflammatory breast cancer or granulomatous mastitis with abscess. A core needle biopsy led to drainage of pus. Gram staining did not reveal any bacteria in the pus, but the colonies from the biopsy grew on blood and chocolate agar cultures. Mass spectrometry detected M. chelonae in these colonies. Histopathological findings revealed mastitis without malignancy. The patient's treatment regimen was oral clarithromycin (CAM) based on susceptibility. Three weeks later, although the pus had reduced, the induration in the breast did not resolve; therefore, multidrug antibiotic treatment was initiated. The patient received amikacin and imipenem infusion therapy for 2 weeks, followed by continuation of CAM. Three weeks later, tenderness in the right breast recurred with slight pus discharge. Hence, minocycline (MINO) was added to the treatment. The patient stopped CAM and MINO treatment 2 weeks later. There was no recurrence 2 years after treatment.
We report a case of M. chelonae breast infection and abscess formation in a 22-year-old Japanese woman without obvious risk factors. M. chelonae infection should be considered in cases of intractable breast abscess, even in patients without immunosuppression or trauma.
龟分枝杆菌是一种非结核分枝杆菌，通常在免疫抑制或创伤患者中引起皮肤、软组织、眼部、肺部、导管相关及术后感染。龟分枝杆菌引起的乳腺感染罕见，大多数病例发生在美容手术后。在此，我们报告首例由龟分枝杆菌引起的自发性乳腺脓肿病例。
一名22岁日本女性因右乳肿胀疼痛2周前来我院就诊，无发热。她育有一名19个月大的孩子，产后1个月停止哺乳。患者无创伤或乳腺手术史，无乳腺癌家族史，且无免疫功能低下。乳腺超声检查发现一个不均质低回声病变，有多个液性暗区，怀疑为脓肿。动态对比增强磁共振成像显示右乳上半部分有一个64×58×62mm、边界不清、高信号强度的病变，有多个环形强化。初步诊断为炎性乳腺癌或伴有脓肿的肉芽肿性乳腺炎。粗针活检引出脓液。革兰氏染色未在脓液中发现任何细菌，但活检组织的菌落可在血琼脂和巧克力琼脂培养基上生长。质谱分析在这些菌落中检测到龟分枝杆菌。组织病理学检查结果显示为乳腺炎，无恶性病变。根据药敏结果，患者的治疗方案为口服克拉霉素（CAM）。3周后，虽然脓液减少，但乳腺硬结未消退；因此，开始使用多药联合抗生素治疗。患者接受阿米卡星和亚胺培南静脉输注治疗2周，随后继续服用CAM。3周后，右乳再次出现压痛并伴有少量脓液排出。因此，治疗中加用米诺环素（MINO）。2周后患者停止CAM和MINO治疗。治疗后2年无复发。
我们报告了一例22岁无明显危险因素的日本女性发生龟分枝杆菌乳腺感染及脓肿形成的病例。即使在无免疫抑制或创伤的患者中，对于难治性乳腺脓肿病例也应考虑龟分枝杆菌感染。
