Pulmonary and cutaneous infection caused by Nocardia farcinica in a patient with nephrotic syndrome

Rationale: Nocardia species is known as conditional pathogenic bacteria. Disseminated infection caused by Nocardia species is rare and occurs primarily in immunosuppressed patients. Signs and symptoms of this infection are frequently nonspecific making early diagnosis and treatment difficult. Patient concerns: We report a case of subcutaneous and pulmonary nocardiosis due to Nocardia farcinica (N farcinica) in a patient with nephrotic syndrome who is undergoing long-term corticosteroid therapy. In this patient, systemic and pulmonary symptoms (usually found in nocaria infection) such as fever, cough, and expectoration were absent. Diagnoses: Early diagnosis was made by pus culture from subcutaneous abscesses and 16S rRNA gene sequencing, which confirm the diagnosis of N farcinica infection. Interventions: The patient was treated with combination therapy of cefatriaxone and trimethoprim-sulfamethoxazole (TMP-SMX) for 2 weeks, and the treatment with TMP-SMX continued to 6 months. Outcomes: The abscesses were cured in 4 weeks and a lesion in the upper lobe of left lung resolved in 3 months. Lessons: This case indicates that disseminated infection due to N farcinica could occur in patients with nephrotic syndrome, even during the period of maintenance therapy with a low-dose corticosteroid and common signs and symptoms of infections could be absent.