Severe H1N1-associated acute respiratory failure in immunocompromised children.

BACKGROUND

Severe pandemic influenza A (H1N1) infection can lead to acute respiratory failure (ARF) with associated high mortality. Children with malignancy may be at higher risk of H1N1-associated ARF because of underlying primary disease or immunosuppression associated with chemotherapy.

PROCEDURE: We describe the clinical course and outcome of critically ill pediatric oncology/hematology patients with H1N1-associated ARF.

RESULTS

Five patients were admitted to the St. Jude Children's Research Hospital (SJCRH) ICU with H1N1 infection during the 2009-2010 influenza season. Underlying diagnoses included 2 patients with acute lymphoblastic leukemia and one each with neuroblastoma, brainstem glioma, and hemolytic anemia secondary to pyruvate kinase deficiency. All patients were mechanically ventilated secondary to ARF following unsuccessful trials of non-invasive ventilatory support. The majority of patients (4/5) required inotropic support, and none required dialysis. Further measures to support their ARF included high frequency oscillatory ventilation in 2 patients, nitric oxide in 3 patients, and surfactant in 1 patient. Three patients had bronchopleural air leak. All patients received oseltamivir; however, 2 were switched to intravenous zanamivir once resistance to oseltamivir was documented. Mean duration of mechanical ventilation was 24 ± 6.8 days and mean duration of ICU admission was 37 ± 12 days. All patients survived to hospital discharge.

CONCLUSION

Our series suggests an overall favorable outcome in immunocompromised children with H1N1-related ARF. Our experience underscores the value of aggressive support during H1N1-related ARF, and early detection and management of oseltamivir-resistant H1N1 infection in this high-risk population.