[Pulmonary co-infection with Nocardia otitidiscaviarum and Aspergillus: a case report]

Nocardia is a rarely encountered opportunistic gram-positive bacterium that exhibits marked invasiveness and dissemination. Typically, acquired through trauma or inhalation, this pathogen primarily affects immunocompromised individuals and is a potentially life-threatening risk in severe cases. Nocardia otitidiscaviarum is a particularly rare subtype of Nocardia infection, and the occurrence of concurrent Aspergillus infection is extremely rare. In cases where both infections manifest concomitantly, rapid and accurate diagnosis is essential to facilitate the subsequent selection of appropriate anti-infective interventions. This paper reported the diagnostic and therapeutic experience in managing a case of pulmonary co-infection with Nocardia otitidiscaviarum and Aspergillus. The patient presented with an acute onset, rapid progression, and early manifestation of respiratory failure. The diagnostic process included respiratory pathogen culture and bronchoscopy, which was supplemented with targeted next-generation sequencing (tNGS). These comprehensive diagnostic modalities led to the identification of pulmonary co-infection with Nocardia otitidiscaviarum and Aspergillus. After adjustment of the antibiotic regimen, the patient's condition improved rapidly, culminating in a timely discharge.