Co-infection with nocardia and mycobacterium tuberculosis in a patient with systemic lupus erythematosus: A case report

Objective: Pulmonary infection is an important cause of morbidity and death in immunosuppressed patients. Recent studies showed that infections caused by Nocardia are quite rare, especially mixed infections with Nocardia and Mycobacterium Tuberculosis (MTB). This case emphasizes the importance of being alert to the possibility of coinfection in immunosuppressed patients. Case description: A 31-year-old female patient presented to the outpatient clinic with recurrent fever and cough. She had also suffered from Systemic Lupus Erythematosus (SLE) and type V lupus nephritis for 8 years. Additionally, she tested positive for the Nocardia nova complex and MTB following culture of the sputum/bronchoalveolar lavage fluid (BALF) and lung tissue. Initial Computed Tomography (CT) showed a bi-pulmonary massive high-density shadow with multiple cavities, Ground-Glass Opacity (GGO) and multiple miliary nodules. After admission, the patient was given Cefoperazone-Sulbactam (CSL) for empiric treatment and also received low-flow oxygen therapy. Four days later, microscopic examination suggested infection with Nocardia and CSL was replaced with Trimethoprim/Sulfamethoxazole (SXT), Moxifloxacin (MFX) and Imipenem (IPM). On the 9th day, the Nocardia nova complex was confirmed although there was a significant improvement in pulmonary symptoms and imaging results. However the images showed that there was no significant change in GGO and miliary nodules. Moreover, 18 days later she was confirmed with MTB infection and was subsequently transferred to the infectious diseases hospital for further treatment. Conclusion: Immunosuppressed patients have higher morbidity and mortality after opportunistic infection with pulmonary pathogens such as Nocardia and MTB. Therefore, early detection of pathogens and selection of appropriate antimicrobial therapy can significantly improve the prognosis.