High mortality from Pneumocystis jirovecii pneumonia in older adults with ILD: a missed opportunity for prophylaxis?

Introduction 

Interstitial lung disease (ILD) is increasingly encountered in older adults, many of whom require prolonged or high-dose corticosteroids with additional immunosuppressive therapy. Although these treatments improve disease control, they increase the risk of Pneumocystis jirovecii pneumonia (PJP), an opportunistic infection associated with significant mortality. Current guidance recommends considering PJP prophylaxis in high-risk patients, yet uptake in routine practice remains inconsistent. We evaluated the characteristics and outcomes of PJP in older adults with ILD to identify opportunities to improve prescribing safety and reduce avoidable mortality. 

Methods 

A five-year retrospective study was undertaken at East Sussex Healthcare NHS Trust of patients with PJP detected on sputum or bronchoalveolar lavage samples. Demographics, immunosuppressive treatment, corticosteroid exposure, prophylaxis use and clinical outcomes were reviewed. 

Results 

Forty-two patients were diagnosed with PJP, of whom 11 (26.2%) had underlying ILD. The mean age was 74.4 years, and 81.8% (n=9) were male. Long-term corticosteroid therapy was prescribed in 81.8% (n=9), and all patients receiving corticosteroids were also receiving additional immunosuppressive therapy. Rituximab was prescribed in 36.4% (n=4), mycophenolate in 18.2% (n=2), and 36.4% (n=4) had received pulsed methylprednisolone within the preceding three months. No patient had received co-trimoxazole prophylaxis. Overall mortality was 81.8% (n=9), with a mean time to death of 20.7 days following diagnosis. 

Conclusion 

Older adults with ILD receiving corticosteroids and additional immunosuppressive therapy experienced very high mortality following PJP, despite none receiving prophylaxis. As geriatricians and respiratory physicians increasingly co-manage older adults with ILD, consideration of PJP prophylaxis should become an integral part of prescribing decisions when initiating prolonged or high-dose corticosteroids. Prospective studies are needed to define optimal prophylaxis strategies in this vulnerable population.