Unique presentation of late‐onsetPneumocystis pneumonia in a pediatric kidney transplant recipient

Abstract Background Restrictive lung disease leading to abnormal lung function in kidney transplant recipients is commonly associated with noninfectious complications or medications used for post‐transplant immunosuppression. Herein, we report an interesting case of pediatric kidney transplant recipient with weight loss and abnormal spirometry who was diagnosed to have late‐onset Pneumocystis pneumonia. Case Report A 17‐year‐old male patient with a history of allergic rhinitis, mild persistent asthma, and deceased donor kidney transplant, performed 18 months prior, presented for routine evaluation of his asthma to the pulmonology clinic. He was clinically asymptomatic except for a weight loss of 8 kg over 6‐month period prior to presentation. Patient's spirometry was suggestive of a restrictive pattern and further investigation using a high‐resolution computed tomography (HRCT) of the chest showed bilateral diffuse ground‐glass reticulonodular opacities with subpleural sparing suggestive of interstitial pneumonitis. A bronchoscopy with bronchoalveolar lavage revealed organisms consistent with Pneumocystis jirovecii on gomori‐methenamine‐silver (GMS) staining. Beta‐d‐glucan testing in serum revealed a level of >500 pg/mL (normal 0‐59 pg/mL) further supportive of Pneumocystis jirovecii infection. Patient was treated with a 6‐week course of trimethoprim‐sulfamethoxazole. His weight loss and beta‐d‐glucan levels improved over a course of 6 months, and he continues to be on trimethoprim‐sulfamethoxazole prophylaxis. Conclusion Late‐onset Pneumocystis jirovecii infection in kidney transplant recipients can have an atypical presentation. Treating physicians should consider PJP in the differential diagnosis of unexplained weight loss in pediatric kidney transplant recipients, especially those receiving a large cumulative burden of immunosuppression.