克氏棒状杆菌感染相关性非哺乳期乳腺炎的细菌学与病理学分析

Bacteriological and pathological analysis of non-lactation mastitis associated with Corynebacterium kroppenstedtii infection

目的探讨克氏棒状杆菌感染相关性非哺乳期乳腺炎的细菌学与病理学特点。方法对2019年1月-2020年12月香港大学深圳医院乳腺外科88例克氏棒状杆菌相关性非哺乳期乳腺炎患者的临床资料进行回顾性分析,分析克氏棒状杆菌的培养及鉴定特性、药敏结果,以及本病的病理学特点。结果88例非哺乳期乳腺炎的女性患者平均年龄为(33.89±5.74)岁,其中78例(88.6%)患者有妊娠史,产后平均(32.64±24.34)个月发生非哺乳期乳腺炎。乳腺标本培养至基质辅助激光解析电离飞行时间质谱(MALDL-TOF MS)鉴定为克氏棒状杆菌的时间平均为(4.62±2.24)d,MALDL-TOF MS鉴定与Nanopore进行16S r DNA测序鉴定结果一致。全部克氏棒状杆菌菌株对青霉素、万古霉素和利福平敏感,只有22株(25%)对克林霉素敏感及红霉素敏感,所有菌株对环丙沙星耐药。50例患者进行乳腺组织病理活检,其中27例(54%)表现为肉芽肿性乳腺炎,镜下可见乳腺小叶为中心的炎症伴以中性粒细胞为主的炎性细胞浸润及非干酪性肉芽肿形成;23例(46%)表现为急慢性炎症,镜下小叶内或导管周围见浆细胞、淋巴细胞及中性粒细胞等炎性细胞浸润,未见肉芽肿结构。结论延长乳腺标本的培养时间可提高克氏棒状杆菌检出率,使用质谱鉴定和16S r DNA测序鉴定克氏棒状杆菌较准确。本病的病理类型可表现为肉芽肿性乳腺炎或非肉芽肿性乳腺炎,此两种类型在病理上可能属于同一疾病的不同阶段。

Objective To investigate the bacteriological and pathological characteristics of non-lactation mastitis associated with Corynebacterium kroppenstedtii infection.Methods The clinical data of 88 patients with non-lactation mastitis associated with Corynebacterium kroppenstedtii infection were retrospectively analyzed,which was from the department of breast surgery of the University of Hong Kong-Shenzhen Hospital,between January 2019 and December 2020.The culture and identification characteristics,drug sensitivity results of Corynebacterium kroppenstedtii and pathological characteristics were analyzed.Results The mean age of 88 patients with non-lactation mastitis was(33.89±5.74)years old;of which,78(88.6%)had a history of pregnancy,and the mean postpartum mastitis was(32.64±24.34)months.The average incubation time of breast-related specimens was(4.62±2.24)days that could be identified as Corynebacterium kroppenstedtii by matrixassisted laser desorption/lonization time of flight mass spectrometry(MALDL-TOF MS).MALDL-TOF MS results were consistent with 16S rDNA sequencing by nanopore.All strains were sensitive to penicillin,vancomycin and rifampicin;22strains(25%)were sensitive to clindamycin and erythromycin,and all strains were resistant to ciprofloxacin.A total of50 patients underwent breast biopsy,27(54%)presented with granulomatous mastitis,lobule-centered granulomatous inflammation was observed by microscopy,accompanied by neutrophil-dominated inflammatory cell infiltration and noncaseous granuloma formation;23(46%)with acute and chronic inflammation,inflammatory cells such as plasma cells,lymphocytes and neutrophils were seen in the lobules or around the ducts,but no granuloma.Conclusions The detection rate of Corynebacterium kroppenstedtii could be improved by prolonging the incubation time of breast specimens.MS and 16S rDNA sequencing methods used to identify Corynebacterium kroppenstedtii were reliable.The histological type of this disease showed granulomatous mastitis or non-granulomatous mastitis,which might belong to different stages of the same disease.