Benign transient hyperphosphatasemia in the pediatric population: a single center cohort study

Alkaline phosphatase (ALP) can be increased in a benign condition known as benign-transient hyperphosphatasemia (BTH). We aimed to evaluate the demographic, and clinical characteristics of infants and children with BTH.

In our retrospective study, infants and children diagnosed with BTH between September 2019 and September 2023 were included.

Of 249 children with elevated ALP levels, 95 (38.1 %) had BTH. The mean age at diagnosis of children with BTH was 2.4 ± 1.3 years (min 0.6 - max 6.2 years). ALP mean value was 2,587 ± 1252 U/L (min 972 - max 5757 U/L). ALP value was an average 7.4 ± 3.6 times higher than the corresponding upper limit of normal. The second measurement was made after an average of 13.2 ± 6 days, and a statistically significant difference was detected compared to the first value, with a decrease of 61 ± 23 % in the ALP value (p<0.001). ALP value returned to normal in an average of 44 ± 29.2 days. Elevated ALP was detected during infection in 49 (51.6 %) children. When the sample was divided into those under 2 years of age and aged 2 and over, no statistical difference was observed in ALP levels in the time it took for ALP levels to return to the normal range (p=0.480).

BTH should be kept in mind if high serum ALP is detected in children without clinical or laboratory suspicion of bone or liver disease. In the follow up detecting a significant decrease trend compared to the first value may be guiding for BTH.