Lovecchio Antonio, Bazzacco Giulia, Di Bella Stefano, Di Meo Nicola, Luzzati Roberto
Infectious Diseases Unit, Trieste University Hospital, Trieste, Italy.
Dermatology and Venereology Department, Dermatology Clinic, University of Trieste, Trieste, Italy.
Infez Med. 2022 Jun 1;30(2):285-292. doi: 10.53854/liim-3002-15. eCollection 2022.
is a genus of aerobic actinomycetes that are usually responsible for opportunistic infection in immunocompromised patients. Less frequently nocardiosis can interest immunocompetent population, causing especially primary cutaneous infections. Cutaneous involvement by spp. may occur mostly as one of four clinical manifestations: superficial cellulitis or abscess, mycetoma, lymphocutaneous (also defined "sporotrichoid") infection and secondary cutaneous involvement from systemic disease. Infections usually present after minor local injury, especially in traumatic outdoor activities (. gardeners, farmers, road accidents), with subsequent environmental contamination of the wound. In sporadic cases cutaneous infection follows an insect bite. Microbiological diagnosis is often difficult to obtain and is the species isolated in most cases (80%). We present the case of a 45-year-old female with fever and a painful and necrotizing lesion on her right leg with secondary ascending lesions occurred on the homolateral knee and consensual groin lymphadenopathy after insect sting (maybe a spider bite). Cultures on skin biopsy identified . Infection was completely healed after 5 months of targeted antibiotic therapy. In addition, we performed a literature review of all cutaneous nocardiosis cases in immunocompetent individuals, finding that only in 22 cases the infection presented after insect bite; in most of these cases lymphocutaneous manifestation was seen and was the species isolated. Our case, along with others in literature, reveals that the real burden of soft-tissues nocardiosis seems low but probably many cases might go undiagnosed because of difficulties in microbiology diagnosis. Primary cutaneous nocardiosis should be included in the diagnostic pathway in cases of cellulitis following insect bite or sting, especially when localized to extremities.
是需氧放线菌的一个属，通常导致免疫功能低下患者发生机会性感染。较少见的是，诺卡菌病可累及免疫功能正常人群，尤其引起原发性皮肤感染。诺卡菌属引起的皮肤受累主要可表现为以下四种临床表现之一：浅表蜂窝织炎或脓肿、足菌肿、淋巴管皮肤（也定义为“孢子丝菌样”）感染以及全身性疾病引起的继发性皮肤受累。感染通常在轻微局部损伤后出现，尤其是在户外创伤性活动（如园艺工人、农民、道路交通事故）后，随后伤口受到环境污染。在散发病例中，皮肤感染继发于昆虫叮咬。微生物学诊断往往难以获得，且在大多数情况下（80%）分离出的是该菌。我们报告一例45岁女性病例，该患者在被昆虫蜇伤（可能是蜘蛛叮咬）后，右腿出现发热、疼痛性坏死性病变，同侧膝关节继发上行性病变，并伴有腹股沟淋巴结病。皮肤活检培养鉴定出该菌。经过5个月的针对性抗生素治疗，感染完全愈合。此外，我们对免疫功能正常个体的所有皮肤诺卡菌病病例进行了文献综述，发现仅有22例感染在昆虫叮咬后出现；在这些病例中，大多数可见淋巴管皮肤表现，且分离出的是该菌。我们的病例以及文献中的其他病例表明，软组织诺卡菌病的实际负担似乎较低，但由于微生物学诊断困难，可能有许多病例未被诊断出来。在昆虫叮咬或蜇伤后发生蜂窝织炎的病例中，尤其是局限于四肢时，原发性皮肤诺卡菌病应纳入诊断流程。
