Risk stratification of immunocompromised children, including pediatric transplant recipients at risk of severe respiratory syncytial virus disease

Background Respiratory syncytial virus (RSV) infection is associated with increased morbidity and mortality in immunocompromised patients. Our goal was to develop a framework for risk stratifying immunocompromised patients, including transplant patients, for RSV prophylaxis. Methods Risk factors for severe RSV disease in immunocompromised patients were identified in the literature and by an expert panel via survey. Experts assigned a probability of developing severe disease (0 to 100 scale) to the risk factors for each immunocompromised population. The results were validated using a clinical dataset. Linear mixed models adjusted for within-expert clustering of ranks were used to estimate average scores, and differences were tested using paired t tests. Logistic regression was utilized to identify important determinants of severe RSV disease. Results The survey was emailed to twenty-seven experts and thirteen responded (48%). Across all transplant groups, age <2 years (mean 77.1, 95% CI 71.7, 82.5) and day care attendance (mean 72.8, 95% CI 67.3, 78.3) were assigned the highest risk of severe disease. The highest risk groups were lung transplant recipients (mean 73.2, 95% CI 67.6, 78.8), combined lung and heart transplant recipients (mean 75.2, 95% CI 69.6, 80.7), allogeneic stem cell transplant (mean 76.0, 95% CI 70.4, 81.6), and severe combined immunodeficiency (mean 74.7, 95% CI 69.1, 80.3). Conclusion The results provide a logical validity to current practice and provide guidance for prioritizing patients to receive prophylactic agents to prevent severe RSV disease. The results will facilitate the development of a risk stratification tool for RSV prophylaxis for immunocompromised patients.