To investigate the clinical manifestations, diagnosis, differential diagnosis and treatment of skin and soft tissue actinomycosis and to improve the wound surgeons’ understanding of skin and soft tissue actinomycosis.

One case of skin and soft tissue actinomycosis on the back was reported and related literatures with "actinomycosis, actinomycete infection, skin, soft tissue" and "actinomycosis, cutaneous, soft tissue" reviewed as searching terms in CNKI and PubMed, respectively.

Compared with searched 20 literatures, it was typical with self-characteristic on the clinical manifestation, diagnosis, differential diagnosis and treatment. In this case, there was no obvious cutaneous mass on admission, but it was typical of multiple sinuses accompanied by more brown pus in the subcutaneous infected tissue. Actinomycetes were cultured from the patient on the 9th day after admission, however, no typical "sulfur particles" were observed by naked eye, bacterial culture and histopathology. The physical examination, intraoperative findings and auxiliary examination results of this case were highly similar to the clinical manifestations of gas gangrene, so that it was highly suspected of clostridium perfringens infection at first. But clostridium perfringens was not detected by repeated bacterial culture and smears. The treatment mainly included general treatment, surgical debridement and the use of antibiotics.

Primary skin and soft tissue actinomycosis is a rare disease with various clinical manifestations. There is relatively typical characteristics but no specificity. Therefore, the diagnosis should be considered comprehensively and differentiated carefully. Because of the low morbidity and difficulty in diagnosis, wound surgeons should pay attention to skin and soft tissue actinomycosis and make the correct diagnosis and treatment early.