Transient hyperphosphatasemia of infancy.

Striking transient increases in serum alkaline phosphatase in 6 infants are reported. Isoenzymes were studied in 3 infants and increased activity was found in bone as well as in liver fractions. Repeated serum determinations demonstrated a duration of about 11 weeks with a peak serum value in the 6th week. The etiology is unknown but an infectious cause is discussed. The condition may be rather frequent but gives no obvious symptoms. It is important to know this condition to avoid unnecessary diagnostic procedures.