Elevated Alkaline Phosphatase in Children

Diagnostic Approach

• The American Academy of Pediatrics recommends checking for symptoms or signs of disease, such as bone pain, skeletal deformities, growth impairment, dental abnormalities, jaundice, hepatomegaly, or recent illness in children with elevated alkaline phosphatase 1
• A comprehensive metabolic panel, including serum calcium, phosphate, creatinine, liver transaminases, and bilirubin, should be obtained in asymptomatic children with isolated ALP elevation 1
• The Endocrine Society suggests measuring PTH and 25(OH) vitamin D levels to exclude metabolic bone disorders in children with elevated ALP 1, 2

Pathological Causes

• X-linked Hypophosphataemia (XLH) is characterized by low phosphate, elevated ALP, and low TmP/GFR, and requires treatment with oral phosphate supplements and active vitamin D 3, 2
• The National Institute of Diabetes and Digestive and Kidney Diseases recommends avoiding normalization of phosphate levels as a treatment goal in XLH, as fasting phosphate will not normalize with oral supplements 3
• The American College of Gastroenterology suggests considering MRCP if ALP does not normalize with treatment in hepatobiliary disease 4

Monitoring and Management

• The American Academy of Pediatrics recommends monitoring children with confirmed pathological causes, such as XLH, every 3-6 months with height, weight, BMI, blood pressure, ALP, calcium, phosphate, creatinine, PTH, and 25(OH) vitamin D 1, 2
• Annual assessment of growth velocity and clinical evaluation of bone deformities is recommended for children with XLH 1
• The American Dental Association suggests dental visits twice yearly after tooth eruption for children with XLH 2