A 66-year-old man presented and was admitted to the hospital with fever for 3 days and dyspnea for 1 day. The patient had been diagnosed with malignant pemphigus vulgaris and put on prednisolone, methylprednisolone and other immunosuppressive drugs for the past 9 years. On admission, he experienced respiratory failure. The absolute count of regulatory T lymphocytes was 156.67 cells/uL. The lactate dehydrogenase increased to 457 IU/L. The chest computed tomography (CT) scan revealed multiple flaky, fuzzy, and high-density opacities in both lungs (Figure 1A). The patient had been on steroids for a long time. He had obvious hypoxia and had never had any other respiratory symptoms or other infections. On respiratory examination, the patient did not have many rales in the lungs. The lung CT scan showed interstitial changes. PCP, usually treated with sulfonamides, was considered a possible etiology because of his immunocompromised state. Caspofungin is a good treatment of choice for Aspergillus infection, which could not be excluded. For other atypical pathogens, moxifloxacin should be added. Thus he was given trimethoprim-sulfamethoxazole (3 tablets, twice daily for 3 weeks), caspofungin (loading dose, 70mg infused over 1 hour; maintenance dose, 50 mg daily infused over 1 hour for 2 weeks), steroids, and moxifloxacin. Consequently, his respiratory function improved, and his body temperature dropped. PCP was confirmed 4 days later when cysts were found in the sputum (Supplementary Material).
Curiously, the follow-up chest CT suggested an enlarged consolidation in the left upper lobe (Figure 1A-C). The patient was admitted to the hospital again due to cough, expectoration, and intermittent fever. Bronchoscopy was performed for 3 times. Smears and culture of the bronchial brush, tracheal secretions, and bronchoalveolar lavage fluid (BALF) were performed. Lung tissue was taken for culture and pathological examination, and tuberculosis was diagnosed (Figure 2). Antituberculosis treatment (isoniazid 300 mg once daily, rifapentine 600 mg twice weekly, ethambutol 750 mg once daily, and pyrazinamide 500 mg thrice daily) was given for 2 months and later ethambutol and pyrazinamide were excluded. Antituberculosis treatment lasted for 1 year. Simultaneously, traditional Chinese medicine techniques were used to manage the patient's psychological well-being and improve mental state. After 3 years of follow-up, the clinical outcome was good (Figure 3). The patient's complete course is shown in Figure 4.