Pulmonary function following varicella-zoster pneumonia in children with leukemia

Varicella-zoster virus (VZV) is a cause of serious pneumonias in immunosuppressed patients. Although there are reports of residual lung changes in adults following VZV pneumonia, no previous studies of lung function in children following this infection have been done. We studied 11 patients (median age 11 years) who had had VZV pneumonia 1 to 16 years previously. All patients had a primary diagnosis of acute lymphocytic leukemia. Pneumonia was mild in most of the patients: Three had only radiographic evidence of pneumonia and required no supplemental oxygen, and seven required an Fio2 ≤ 0.4 for intervals for up to 11 days. One patient had severe pneumonia and required major ventilatory support. Three patients (27%) had significant restrictive defects on follow-up, with total lung capacity 62–69% predicted; and a fourth was abnormal at 1 month follow-up but normal at 16 months. No obstructive defects were noted, although RV/TLC ratios were elevated in three patients and volume of isoflow increased in three. Single breath diffusing capacity was reduced in two patients, but gas exchange was normal in all. No residual radiographic changes were present except in the patient who had severe pneumonia and increased lung markings at 2 months follow-up. All three patients with restrictive changes had other infections before or following VZV, including Pneumocystis carinil pneumonia in two and recurrent, nonspecific pneumonias in the third. We conclude that VZV pneumonia had minimal residual effects on lung function in children with leukemia.