Varicella pneumonia in a bone marrow-transplanted,immune-reconstituted adenosine deaminase-deficient patient with severe combined immunodeficiency disease

Bone marrow transplantation provides an important modality for enzyme replacement and the immune reconstitution of patients with adenosine deaminase (ADA) deficiency and severe combined immunodeficiency disease. We report a patient with ADA deficiency who develops severe varicella pneumonia 6 years after successful bone marrow transplantation and immune reconstitution. Marked abnormalities in T-cell mitogen responsiveness and pokeweed mitogen-induced polyclonal immunoglobulin synthesis occurred. Coculture experiments suggested the presence of increased suppressor activity. T-cell phenotyping showed decreased T3 and T4 subsets. These abnormalities slowly resolved over several months as the patient recovered from the varicella infection. ADA enzyme levels and metabolite concentrations in urine and erythrocytes remained unchanged. These findings, together with the chromosome and immune studies, suggested that the bone marrow graft remained intact. These studies indicate that immunologically reconstituted ADA-deficient patients may be at higher risk for complications related to varicella infection and suggest that the institution of preventive measures is important.