Bone Marrow Infection by Pneumocystis jirovecii in a Patient with AIDS: A Case Report and Literature Review

Abstract

Background: Pneumocystis jirovecii primarily causes pneumonia in immunosuppressed individuals, particularly those living with advanced HIV/AIDS. Extrapulmonary dissemination is uncommon, with bone marrow involvement described in only a handful of cases globally. Bone marrow infection occurs in the setting of severe immunosuppression, poses diagnostic challenges, and carries a high mortality rate.

Methods: We describe the case of a 34-year-old man newly diagnosed with HIV/AIDS, presenting with severe immunosuppression and Pneumocystis jirovecii pneumonia. The patient initially improved with cotrimoxazole and corticosteroids, but was readmitted shortly after discharge with abdominal pain, diarrhea, and worsening pancytopenia. A bone marrow biopsy revealed Pneumocystis jirovecii cysts, confirming disseminated infection. Concomitant Kaposi sarcoma involving the skin and gastrointestinal tract was also diagnosed. Despite antimicrobial therapy, the patient's condition worsened, leading to multisystem organ failure and death two months later.

Conclusions: This case highlights a rare presentation of disseminated Pneumocystis jirovecii infection with bone marrow involvement in a patient with advanced HIV/AIDS. Although infrequent, this complication should be considered in individuals with Pneumocystis jirovecii pneumonia who develop persistent cytopenias and systemic symptoms. Diagnosis depends on histopathologic confirmation, which may lead to under-recognition. Early suspicion and individualized management are essential, though the optimal treatment approach for extrapulmonary infection remains undefined.

Keywords: AIDS; Pneumocystis jirovecii; bone marrow; case report; extrapulmonary infection; opportunistic infections; pancytopenia.

Figure 1

A computed tomography of the chest showing multiple ground glass opacities randomly distributed in both lung fields.

Figure 2

Bronchoalveolar lavage with, as follows: (A) Hematoxylin-eosin stain revealing foamy and cottony amorphic exudates; (B) PAS (Periodic Acid Schiff) stain highlights round structures with a small central condensation suggestive of P. jirovecii cysts; (C,D) GMS (Grocott–Gömöri’s methenamine silver) stain with magnification revealing dark brown round structures with a “folded spheres” or “flattened beach balls” appearance suggestive of P. jirovecii cysts.

Figure 3

Bone marrow biopsy with, as follows: (A,B) Hematoxylin-eosin stain revealing foamy amorphic exudate; and (C,D) GMS (Grocott–Gömöri’s methenamine silver) stain and magnification revealing dark, round small structures with no budding within myeloid and erythroid cells suggestive of P. jirovecii yeasts.