<i>Pneumocystis jirovecii</i> and <i>Mycobacterium tuberculosis</i> Pulmonary Coinfection in an HIV-Seronegative Patient: A Case Report and Literature Review

Background Coinfection with Pneumocystis jirovecii and Mycobacterium tuberculosis is rare in HIV-seronegative patients. Because it is associated with unknown morbidity and a high mortality rate especially in patients with immunosuppression, health care practitioners should have a high index of suspicion when dealing with such patients. Case presentation A 66-year-old man with glucocorticoid therapy for 9 years had a fever after getting a cold and developed respiratory failure rapidly within 3 days. He was given trimethoprim-sulfamethoxazole empirically before Pneumocystis pneumonia (PCP) was confirmed with the presence of cysts in the sputum. Although there was a partial improvement of symptoms, an area of consolidation on the left upper lung lobe gradually enlarged. Bronchoscopy was performed 3 times and Mycobacterium tuberculosis infection was finally diagnosed. For 1 years, he was treated with standard antituberculosis agents, and his psychological well-being was managed using traditional Chinese medicine techniques. After 3 years of follow-up, his outcome was very good. Conclusion HIV-seronegative patients on long-term glucocorticoid therapy in areas with a high incidence of Mycobacterium tuberculosis may be co-infected with Pneumocystis jirovecii . When opportunistic infections are suspected, diagnostic procedures including invasive ones should be performed as soon as possible and appropriate interventions need to be carried out promptly.