Neonatal adenovirus pneumonia.

A 13-day-old premature infant with hyaline membrane disease was found to have altered pneumocytes, suggesting viral infection. Pneumocytes had nuclear inclusions that were basophilic or eosinophilic with poorly preserved cytoplasm. Monoclonal antibodies specific for the nucleocapsid of herpes simplex virus types 1 and 2 applied to formalin-fixed lung sections were nonreactive. Electron microscopy of lung tissue showed the characteristic crystalline arrays of adenovirus. Documented adenovirus infection, while common in infancy and childhood, is rare in the neonatal period. Light microscopic diagnosis of viral infection lacks specificity, and adenovirus infection may be misdiagnosed. The neonatal lung is vulnerable to viruses other than the more commonly found herpes simplex and cytomegalovirus, and viral culture, immunocytochemistry, or electron microscopy should be used when possible.