Heiner syndrome mimicking an immune deficiency.

Heiner syndrome is a rare but reversible non-IgE mediated hypersensitivity to cow's milk resulting in an atypical pulmonary disease in infants and young children. There isoften a delay in diagnosis in this disorder due to its unusual presentation with heterogeneous manifestations. Such infants usually have chronic or recurrent upper or lower respiratory tract symptoms, suggestive of recurring infections such as otitis media or pneumonia. The patchy infiltrates on chest x-ray are commonly mistaken for pneumonia, yet are refractory to antibiotictreatment. Systemic features such as fever, vomiting, diarrhea, and failure to thrive further contribute to the difficulty in making a prompt diagnosis. Only a few case reports have been published. We report a case of this unique milk-induced pulmonary syndrome in a hospitalized 12-month-old child, which illustrates the importance of considering this diagnosis in any child with unexplained lung infiltrates.