Transient hyperphosphatasemia in an infant with bronchiolitis and pneumonia

We present benign transient hyperphosphatasemia in a 4-month old infant with acute bronchiolitis and pneumonia. During hospitalization the infant had increased catalytic activity of the ALP: 2nd day-5074 U/L, 3rd day 5622-U/L, 8th day-3129 U/L. The X-ray, leukocytosis, and CRP pointed to bacterial etiology of the respiratory disorder. Electrophoretic separation revealed atypical isoenzyme profile: fast anodal, near-cathodal and bone fractions. ALP levels normalized within 54 days, and control electrophoresis revealed the appearance of normal liver, placental/placental-like, intestinal and bone isoenzymes. The appearance of an atypical fast anodal and near-cathodal fractions of ALP in this infant during an acute lower respiratory tract infection and rapid return within the reference intervals points to benign transient hyperphosphatasemia.