TB.IGRA在海分枝杆菌感染诊断和鉴别诊断中的应用

目的:探讨结核感染T细胞γ-干扰素释放实验(TB.IGRA)在海分枝杆菌感染诊断和鉴别诊断中的应用价值。方法:回顾性分析在我院门诊诊疗的疑似海分枝杆菌感染患者,排除结核病患者,根据患者海分枝杆菌qPCR是否阳性分为海分枝杆菌感染组和真菌、普通细菌感染组。应用TB.IGRA检测患者外周血中结核感染特异性T细胞,比较分析TB.IGRA和抗酸染色诊断海分枝杆菌感染的灵敏度、特异度、预测值和似然比;比较不同年龄组中TB.IGRA的灵敏度、特异度差异以及海分枝杆菌感染患者的γ-干扰素水平。结果:共纳入87例海分枝杆菌感染和25例真菌、普通细菌感染患者。TB.IGRA诊断海分枝杆菌感染的灵敏度、特异度分别为73.6%、64.0%,灵敏度较抗酸染色高,特异度较抗酸染色低;其阳性、阴性预测值和似然比分别为87.7%、41.0%、2.04和0.41;青年、中年和老年组的灵敏度分别为70.0%、73.5%、74.4%,中年组特异度最高(88.9%),老年组最低(46.2%)。结论:TB.IGRA在海分枝杆菌感染的诊断和鉴别诊断中具有重要的应用价值。     

海分枝杆菌调控巨噬细胞糖酵解重编程的研究

目的:通过检测海分枝杆菌感染巨噬细胞后糖酵解相关基因的表达和代谢产物乳酸的变化情况探究海分枝杆菌对巨噬细胞糖酵解的调控。方法:利用实时荧光定量PCR检测不同感染条件下海分枝杆菌感染巨噬细胞后糖酵解代谢相关基因(SLC2A1、HK2、LDHA)的表达，同时检测糖酵解代谢最终产物乳酸的浓度。使用流式细胞仪和(或)共聚焦显微镜检测不同感染条件下巨噬细胞内葡萄糖摄取情况以及细胞内海分枝杆菌的荧光强度。结果:海分枝杆菌感染增加了巨噬细胞对葡萄糖的摄取，并以感染时间和感染复数依赖的方式促进巨噬细胞糖酵解代谢相关基因(SLC2A1、HK2、LDHA)的表达和乳酸的产生。与热灭活的海分枝杆菌相比，活的海分枝杆菌抑制糖酵解相关基因(SLC2A1、HK2、LDHA)的表达和乳酸的产生。此外，使用2-脱氧葡萄糖抑制糖酵解代谢酶HK2的活性促进了细胞内海分枝杆菌的存活。结论:糖酵解重编程是巨噬细胞对海分枝杆菌感染的免疫防御机制之一，而海分枝杆菌可通过调控巨噬细胞糖酵解促进自身在胞内的存活。因此，通过调控巨噬细胞的糖酵解可能是控制海分枝杆菌感染的潜在干预措施。     

光动力疗法辅助治疗海分枝杆菌感染一例

海分枝杆菌感染的典型特征为皮肤感染性肉芽肿。抗生素是治疗海分枝杆菌皮肤感染的首选药物。本文报道了一例海分枝杆菌感染的中年女性,由于抗生素不耐受,给予光动力治疗和点阵激光辅助加速治疗后成功治愈。     

累及皮肤和肌腱的难治性海分枝杆菌感染一例

患者,男,53岁。右上肢结节半年。皮肤科查体：右上肢见多发暗红色丘疹、结节,部分结节破溃,可见脓血性分泌物,伴右手肿胀,皮温正常,轻度压痛。皮肤组织病理检查符合感染性肉芽肿;组织分枝杆菌培养为海分枝杆菌;海分枝杆菌qPCR(组织)为阳性,B超提示右手指伸肌腱腱鞘炎,结合临床表现及实验室检查诊断为海分枝杆菌感染。给予米诺环素、克拉霉素治疗2个月,效果欠佳,结合药敏结果调整方案为利福平、克拉霉素、多西环素、氨苯砜治疗,5个月后右上肢丘疹、结节基本消失。     

鱼刺伤肉芽肿二例

报道2例鱼刺伤肉芽肿患者。2例患者均有鱼类接触史、组织病理示感染性肉芽肿、结核分枝杆菌γ-干扰素体外释放定量试验(TB-IGRA)阳性、结核感染T细胞γ干扰素升高、海分枝杆菌qPCR阳性。结合其病史、组织病理、TB-IGRA、海分枝杆菌qPCR等确诊为鱼刺伤肉芽肿。2例患者均予以克拉霉素缓释片、利福平胶囊治疗后痊愈。     

海分枝杆菌皮肤感染一例

患者,女,38岁。处理海鲈鱼时,双手多处被鱼刺扎伤。后于受伤部位出现浸润性斑块、溃疡。清创治疗、抗细菌及抗真菌治疗无效。组织活检病理提示感染性肉芽肿,组织培养海分枝杆菌阳性,组织DNA行特异性real time PCR检测海分枝杆菌阳性。予以患者利福平、克拉霉素、乙胺丁醇治疗3个月,皮疹完全消退。随访一年未复发。     

鱼刺伤致腱鞘炎二例

鱼刺伤肉芽肿是因鱼刺伤后被海分枝杆菌感染引起的肉芽肿性损伤,上肢是最常见的感染部位。通常情况下,所报道的病例多表现为皮肤表面的结节、红斑。累及肌腱、骨骼、关节等深部结构较为少见。现报道因海分枝杆菌感染导致的腱鞘炎两例。     

分枝杆菌在北京水源环境中的分布:M.arupense国内首次报告

目的:研究北京水源中分枝杆菌的分布,应用表型鉴定方法和分子生物学方法进行分枝杆菌鉴定,并比较两种方法的准确性和优缺点.方法:采集水源环境标本,进行分枝杆菌分离培养,通过生化反应对所有分离株进行鉴定.同时从培养菌落中提取分枝杆菌DNA,用PCR扩增65 ku热休克蛋白基因,扩增产物分别应用两种限制性内切酶BstEⅡ和Hae Ⅲ酶切,进行限制性片段长度多态性(RFLP)分析和PCR产物的测序分析.结果:从30份养鱼水中分离出35株分枝杆菌.①表型鉴定结果:Runyon Ⅰ群1株,可疑为海分枝杆菌;Runyon Ⅱ群7株,确定为戈登分枝杆菌或疑似戈登分枝杆菌;Runyon Ⅲ群9株,未鉴定到种;Runyon Ⅳ群18株,其中龟-偶发分枝杆菌复合群9株,其余9株未鉴定到种.②PCR-RFLP鉴定结果:戈登分枝杆菌8株,龟-偶发分枝杆菌复合群8株(包括M.peregrinum 1株),疑似日内瓦分枝杆菌10株,其余9株未鉴定到种.③PCR产物测序鉴定:戈登分枝杆菌10株,M.arupense9株,偶发分枝杆菌7株,土分枝杆菌6株,不产色分枝杆菌1株,M.peregrinum 1株,脓肿分枝杆菌1株.结论:非结核分枝杆菌(NTM)广泛存在于养鱼水中,分枝杆菌采用65 ku热休克蛋白基因PCR扩增配合测序鉴定较传统表型鉴定和PCR-RFLP更准确.     

海分枝杆菌感染二例并文献复习

报道2例海分枝杆菌感染并复习相关文献.患者1,男,25岁.右侧拇指红肿破溃伴疼痛1个月.患者2,女,54岁.左侧大拇指及手背手腕红斑结节伴疼痛2个月.2例患者均有鱼扎伤病史,常规抗感染治疗无效,最终诊断为游泳池肉芽肿,给予抗分枝杆菌感染治疗3个月后痊愈.     

PCR-RFLP检测皮肤分枝杆菌

目的建立检测8种常见皮肤分枝杆菌的PCR-RFLP方法。方法①用通用引物对分枝杆菌的热休克蛋白hsp65基因序列进行PCR扩增：②用限制性内切酶BstEⅡ和HaeⅢ对扩增产物进行消化,根据所得片段确定各分枝杆菌特征性的酶切图谱,从而对分枝杆菌进行鉴别。结果 8种常见皮肤分枝杆菌感染标准株(鸟、胞内、堪萨斯、结核、瘰疬、海、偶发、龟分枝杆菌)的酶切图谱与文献报道一致。结论 PCR-RFLP方法可用以检测鉴定皮肤分枝杆菌。     

Disseminated Mycobacterium marinum infection with extensive cutaneous eruption and bacteremia in an immunocompromised patient

Mycobacterium marinum can cause fish tank granuloma (or swimming pool or aquarium granuloma) in immunocompetent patients. Dissemination of Mycobacterium marinum-infection is a rare condition which occurs mainly in immunocompromised patients and can be life-threatening. We report the case of an 87-year-old woman who was treated with oral corticosteroids for polymyalgia rheumatica for many years and developed erythema nodosum-like lesions on the right forearm and arthritis of the right wrist. By increasing the steroid dosage and adding methotrexate only short-term remission was achieved. Seven months later painful erythematous nodules occurred on all extremities which became necrotic, ulcerative and suppurative. Ziehl-Neelsen staining revealed acid-fast bacilli and Mycobacterium marinum was cultured from skin biopsies, blood, and urine. The critically ill patient was treated with clarithromycin and ethambutol resulting in a dramatic improvement of the general condition. After four months, doxycycline had to be added because of new skin lesions. This case illustrates the impact of Mycobacterium marinum infection in immunocompromised patients.     

Utility of anti-bacillus Calmette-Guérin antibodies as a screen for organisms in sporotrichoid infections

BACKGROUND: Sporotrichoid infections often present a diagnostic challenge for the dermatopathologist. Therefore an affordable, reliable method of easier recognition of organisms is desired. Recently, immunohistochemical staining with antibodies against Mycobacterium bovis (bacillus Calmette-Guérin, BCG) was found to be useful in identifying various fungi and mycobacteria with minimal background staining. OBJECTIVE: The purpose of this study was to demonstrate the usefulness of anti-BCG antibodies as a screen for organisms in sporotrichoid infections. METHODS: Thirteen specimens of suspected sporotrichosis were selected for staining with anti-BCG antibody. Sporotrichoid infection was confirmed by histochemical staining, biopsy, and follow-up results. RESULTS: Twelve of the 13 specimens stained positively using anti-BCG antibody. Of the 5 cultures done, 2 were positive for M. marinum, and 1 grew Sporothrix schenckii. CONCLUSION: Immunohistochemical staining with anti-BCG antibody offers another screening method to identify organisms in sporotrichoid infections because of its ease, cost-effectiveness, and simplicity.     

Mycobacterium marinum infections treated with tetracycline.

Five cases of Mycobacterium marinum skin infections were successfully treated with 2 gm of tetracycline hydrochloride daily for periods from four to 12 weeks. In each case, the isolated M marinum was sensitive in vitro to tetracycline at levels from 25 to 50 microgram/ml. Tetracycline is recommended as treatment for extensive or sporotrichoid M marinum infections.     

MYCOBACTERIUM MARINUM CUTANEOUS INFECTIONS ACQUIRED FROM OCCUPATIONS AND HOBBIES

Background. Nontuberculous mycobacterial (NTB) infections are not commonly diagnosed in Thailand. The dissertation of reported cases among 10 published reports of 44 cases within 20 years revealed only six cases of cutaneous infections in which M. marinum was not included. Methods. The proven cases of M. marinum infection were studied at the Institute of Dermatology, Bangkok from 1981 to 1990. The clinical data, histopathology, tuberculin test, chest x-ray, and treatments were recorded. Results. M. marinum skin infection accounted for 18 cases (81.8% of NTB skin infection), 10 men and 8 women. A history of preceding trauma occurred in 11 cases (61.1%), most of which were negligible wounds or minor abrasions. Twelve cases (66.7%) were in contact with organisms in their occupations and hobbies associated with fish and water exposure. Conclusions. Eighteen cases of M. marinum cutaneous infection acquired from occupations and hobbies were reported. The term “M. marinum cutaneous infection” or “M. marinum granuloma” instead of swimming pool granuloma or fish tank granuloma was proposed. According to this study, cotrimoxazole was the most appropriate drug for the treatment of M. marinum cutaneous infection.     

Mycobacterium marinum infection simulating interstitial granuloma annulare: a report of two cases

We report two cases of Mycobacterium marinum infection that histologically simulated interstitial granuloma annulare (GA). In one case, an infectious etiology was not suspected in histologic sections, but a tissue culture performed during the patient's clinic visit identified M. marinum, and a subsequent Fite stain revealed mycobacteria. Interstitial granulomatous dermatitis is a rare presentation for cutaneous nontuberculous mycobacteria and has yet to be attributed specifically to M. marinum. In both immunocompetent and immunosuppressed patients, infection with M. marinum should be considered in lesions histologically resembling interstitial GA, particularly when there is clinical suspicion for an infectious process.     

Mycobacterium marinum with associated bursitis.

BACKGROUND: Mycobacterium marinum infections have been reported for over 50 years, mostly in association with trauma in the setting of water exposure. OBJECTIVE: The differential diagnosis for nodules in a sporotrichoid distribution with simultaneous bursitis is discussed. Mycobacterium marinum treatment regimens for skin and joint involvement are reviewed. METHODS: Mycobacterium marinum was identified by skin tissue culture with Lowenstein-Jensen medium at 32 degrees C. Histopathologic findings support mycobacterial infection. RESULTS: Bursitis and nodules resolved in the first 2 months of a 6-month course of minocycline treatment. CONCLUSION: Bursitis is an extremely rare but significant complication of M. marinum.     

Severe Sporotrichoid Fish Tank Granuloma Following Infliximab Therapy

Mycobacterium marinum is an atypical mycobacterium usually found in non-chlorinated water. It rarely disseminates, except in the setting of a severely immunosuppressed patient, and usually follows a sporotrichotic type of distribution. We report the case of a 45-year-old man who had ankylosing spondylitis and was receiving infliximab and isoniazid for latent tuberculosis. The patient presented with a 5-month history of painful erythematous and suppurative nodules and abscesses on the right upper extremity. M. marinum was not isolated in cultures and histologic findings together with clinical examination provided evidence of sporotrichoid-like fish tank granuloma. The patient was treated with rifampin (rifampicin) and ethambutol for 8 months and responded satisfactorily while continuing to receive infliximab. In accordance with data in the published literature, isoniazid proved ineffective in preventing M. marinum infection in this patient. While mycobacterial complications of tumor necrosis factor-alpha (TNFalpha) inhibitor therapy are well established, our case appears to be the first reported instance of M. marinum infection in a patient taking infliximab. As anti-TNFalpha agents become increasingly used for a variety of conditions, awareness of the potential infectious complications associated with use of these agents will be vital for clinicians.     

Mycobacterium marinum infection complicating Crohn's disease, treated with infliximab

Tumour necrosis factor-alpha inhibitors including infliximab are often used to treat a number of recalcitrant medical conditions. These agents are increasingly associated with infections, particularly mycobacterial infections. We report sporotrichoid spread of Mycobacterium marinum in a 37-year-old woman with Crohn's disease, who had been receiving infliximab infusions for 2 years. An infection had spread up the right leg, after she had been swimming on holiday in the Canary Islands. M. marinum was cultured from the lesions and also identified by PCR on formalin-fixed tissue. To our knowledge, this is the first report of M. marinum occurring in a patient receiving infliximab.