Pulmonary infection caused by Nocardia cyriacigeorgica in a patient with allergic bronchopulmonary aspergillosis: A case report

RATIONALE: Nocardia species is known as conditional pathogenic bacteria. Among Nocardia species, pulmonary infection caused by Nocardia cyriacigeorgica associated with Aspergillus fumigatus complex lung disease is rarely reported. PATIENT CONCERNS: A 55-year-old female with a history of productive cough with recurrent expectoration for 20 years presented with increasing cough for 12 months. The patient presented complaining of respiratory symptoms including increasing cough with yellow phlegm, poor appetite, and generalized fatigue for a week prior to admission. DIAGNOSES: Nocardia cyriacigeorgica pneumonia was identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and 16S rRNA gene sequencing. INTERVENTIONS: Combined treatments (trimethoprim-sulfamethoxazole and meropenem) were administered after identification of N cyriacigeorgica. OUTCOMES: The respiratory symptoms of the patient had improved both clinically and radiologically after 4 weeks of antibacterial therapy. LESSONS: Early precise diagnosis and prompt combined therapy are of vital importance in severe Nocardia pulmonary infection.