Clinical analysis of Pneumocystis jirovecii pneumonia in children with malignant disease.

OBJECTIVE

To characterize Pneumocystis jirovecii pneumonia (PJP) in pediatric malignancy patients receiving chemotherapy or glucocorticoids, and provide guidance for timely diagnosis and effective treatment.

METHODS

A retrospective analysis of clinical features, laboratory findings, radiological characteristics, treatment approaches, and outcomes in pediatric malignancy patients who developed PJP.

RESULTS

Ten patients (1:1 male-to-female ratio; median age 6.50 years, range 2.83-14.58 years) were followed for a median of 14 months (range 6-53 months). Eight developed PJP during chemotherapy and two post-completion. Nine received glucocorticoids in their chemotherapy regimen. PJP prophylaxis was either absent (n = 4) or discontinued > 1 month prior (n = 5). Clinical presentations included fever, dyspnea, and wheezing, often without significant cough. Laboratory findings showed elevated (1,3)-β-D-glucan(BDG)in 7 cases. Chest CT typically revealed bilateral diffuse patchy infiltrates, ground-glass opacities, and nodular shadows. All cases had a positive metagenomic next-generation sequencing (mNGS) or targeted next-generation sequencing (tNGS) result for P. jirovecii from sputum or bronchoalveolar lavage fluid (BALF) samples.Treatment included Trimethoprim-sulfamethoxazole(TMP/SMZ) with/without caspofungin and adjunctive corticosteroids. Eight patients required PICU admission (median stay 7.5 days, range 0-45 days) for respiratory support. Nine patients survived PJP, with one PJP-related death and one death from underlying disease.

CONCLUSION

High clinical suspicion for PJP is warranted in pediatric malignancy patients presenting with fever, dyspnea, elevated BDG, and characteristic imaging findings, particularly in those with inadequate prophylaxis. Early pathogen detection and treatment initiation are crucial. While TMP/SMZ remains first-line therapy, combination with caspofungin may improve outcomes. Short-term adjunctive corticosteroids may benefit moderate to severe cases.