Nocardia brasiliensis infection causes skin abscesses around the eyes: A case-report and review of literature.

Nocardia species are widely distributed in environments such as soil. Nocardia brasiliensis is the primary pathogen responsible for primary cutaneous nocardiosis. The clinical manifestations of this disease are often non-specific, making it prone to misdiagnosis. This article reports a case involving a 42-year-old immunocompetent female patient who presented with a right periorbital skin abscess accompanied by cervical lymphadenitis, without a clear history of trauma or insect bite. Empirical antibacterial therapy proved ineffective. The infection was definitively diagnosed as Nocardia brasiliensis by secretion culture (antimicrobial susceptibility testing indicated sensitivity to co-trimoxazole). Based on the susceptibility results, treatment was adjusted to oral trimethoprim-sulfamethoxazole (SMZ-TMP), supplemented by local debridement and drainage. Following significant symptomatic improvement, the patient was discharged and continued with sequential oral SMZ-TMP therapy for two months. Combined with a literature review, this case highlights that: For immunocompetent hosts presenting with progressive periorbital or facial abscesses accompanied by lymphadenitis and lacking typical predisposing factors, cutaneous nocardiosis (particularly infection by N. brasiliensis) should be highly suspected. Early implementation of etiological culture and antimicrobial susceptibility testing is crucial for definitive diagnosis and guiding precise treatment (based on SMZ-TMP), with the prognosis typically being favorable.