Pulmonary nocardiosis due to Nocardia otitidiscaviarum in an immunocompetent host:A case report and literature review

Abstract BackgroundNocardia otitidiscaviarum is a relatively rare pathogen that belongs to the distinctive species within the Nocardia genus. It is typically found in soil or decaying matter and can enter the body through a break in the skin or, less commonly, through the respiratory tract. Pneumonic nocardial disease is an uncommon infection that primarily affects immunocompromised individuals. Case presentationThis article presents a case study of a pneumonic nocardiosis infection in a 22-year-old immunocompetent female with symptoms of fever, cough, and sputum production. The patient had no prior history of diabetes, was not on steroid therapy, had no adverse lifestyle habits, and had not been diagnosed with tuberculosis previously. A chest CT scan revealed suppurative inflammation in both lungs. Bronchoscopy was conducted, and alveolar lavage fluid was collected and sent for culture and next-generation sequencing (NGS). NGS results confirmed the presence of Nocardia otitidiscaviarum within 24 hours. After 96 hours of conventional laboratory culture, positive colonies were observed. The morphological features of bacteria in these colonies were consistent with Nocardia otitidiscaviarum, as confirmed by Gram staining. The patient received precise antibiotic treatment and showed positive outcome. We conducted a review of previously documented cases involving infections caused by Nocardia otitidiscaviarum. ConclusionsEnhanced recognition of the diverse presentations of Nocardia otitidiscaviarum could potentially elevate the survival rate of this otherwise lethal condition.