A 32-year-old man visited a hospital with abnormal chest X-ray findings from routine medical check-up in 2014. On initial chest X-ray and CT, disseminated multiple granulomatous nodules with cavitation were observed on whole lung field (Fig. 1A and B). He was revealed to be HIV positive with western blot assay; his initial CD4+ T lymphocyte count was 56/mm³ and HIV ribonucleic acid (RNA) was 410,000 copies/mL on polymerase chain reaction (PCR) test. Antigen test for Cryptococcus was negative but P. jirovecii was detected from bronchoalveolar lavage (BAL) specimen on PCR test. Accordingly, we started intravenous trimethoprim/sulfamethoxazole (TMP/SMX) and intravenous amphotericin B, suspecting PJI combined with fungal infection. However, there was no improvement in pulmonary nodules at follow-up chest X-rays. On the 13th day of hospitalization, he received open lung biopsy by video-assisted thoracoscopic surgery. Histopathologic examination observed the necrotizing granulomas in lung parenchymal tissue and alveolar spaces filled with pink, foamy exudate containing oval shaped fungal cysts on hematoxylin and eosin (H & E) and gomori methenamine-silver (GMS) stain (Fig. 1E-G). Bacteria, acid-fast bacilli or other fungal species were not observed. Subsequently, TMP/SMX treatment was maintained and amphotericin B was discontinued. After 2 weeks of TMP/SMX therapy, we changed the regimen to oral clindamycin plus primaquine because leukopenia and thrombocytopenia developed. A total of 21 days of antibiotics therapy against PJI was maintained. After completion of PJI therapy, the size of multiple cavitary nodules was decreased at follow-up chest CT (Fig. 1C), and he was finally discharged on hospital day 34. At outpatient clinic, we observed gradual disappearance of multiple nodules on follow-up X-rays (Fig. 1D).

A 43-year-old man visited a hospital with loss of vision in the left eye and right pleuritic chest pain which began 15 days prior in 2015. He was a known HIV patient but had voluntarily stopped highly active antiretroviral therapy (HAART) since 3 years prior. His initial CD4+ T lymphocyte count was 20/mm³ and HIV RNA was 57,900 copies/mL. Retinal hemorrhage was compatible with cytomegalovirus (CMV) retinitis at fundoscopic examination, thus we started intravenous ganciclovir therapy subsequently. Additionally, a 13.35 cm² of lobulated homogeneously enhancing mass-like lesion on right lower lobe with mild filling defect of right descending pulmonary artery was observed at initial chest CT (Fig. 2A and B). We started enoxaparin under the diagnosis of pulmonary infarction. On the 11th day of hospitalization, aggravation of retinal hemorrhage and retinal detachment were observed at fundoscopic examinations; enoxaparin was stopped on hospital day 11 and vitrectomy with silicon oil insertion was performed on hospital day 14. On hospital day 23, follow-up chest CT showed that the initial mass-like lesion was augmented (18.30 cm²), and he underwent fine needle aspiration biopsy (FNAB). Histopathologic examination revealed the fibrotic granulomatous lesions with amorphous bubbly necrotic area which contained oval shaped fungal cysts on H & E and GMS stain (Fig. 2E and F). We started oral TMP/SMX subsequently. After 2 weeks, we changed the regimen to oral clindamycin plus primaquine because the patient experienced visual hallucination as a side effect of TMP/SMX. A total of 28 days of antibiotics therapy against PJI was maintained and he was finally discharged on hospital day 63. At outpatient clinic, we observed decreased mass size (5.87 cm²) on follow-up chest CT (Fig. 2C and D).

A 39-year-old man visited a university hospital with cough, sputum and dyspnea that began 14 days prior in 2014. On initial simple X-ray and chest CT, diffuse ground-glass opacity was observed on whole lung field. In addition, multiple hepatic nodules, enlarged intra-abdominal lymph nodes, and diffuse jejunal wall thickening were found incidentally (Fig. 3A and B). He was revealed to be HIV positive with western blot assay; his initial CD4+ T lymphocyte count was 20/mm³ and HIV RNA was 57,900 copies/mL. P. jirovecii was detected on sputum PCR and we started intravenous TMP/SMX subsequently. For differential diagnosis of hepatic nodules, intra-abdominal lymph node enlargement and jejunal wall thickening from other diseases such as lymphoma, he underwent FNAB of the liver and received a positron emission tomography (PET)-CT on hospital day 7 and 10, respectively. PET-CT showed no increased metabolic uptake (Fig. 3C and D). On histopathology of liver biopsy, necrotizing granuloma without evident organisms was found on H & E and GMS stain (Fig. 3G and H). Under the diagnosis of extrapulmonary manifestation of PJI, we determined to treat him with TMP/SMX only and observe the clinical progress. On follow-up CT performed on hospital day 17, a significant improvement was observed in the aforementioned lesions (Fig. 3E and F). He received TMP/SMX for a total of 3 weeks, and was finally discharged on hospital day 28. Abnormal findings disappeared on follow-up CT at outpatient clinic.