infantile hypophosphatasia

Infantile hypophosphatasia is a very rare and severe form of hypophosphatasia that primarily affects infants, manifesting as rickets without the typical elevation of serum alkaline phosphatase activity. It results from pathogenic variants in the ALPL gene, which compromise enzyme function necessary for proper bone mineralization. Although precise prevalence data is unavailable, the condition is understood to be extremely rare. Early clinical signs in infancy are critical for prompt diagnosis and management of the many complications associated with poor bone mineralization.

The hallmark clinical features include phosphoethanolaminuria and decreased circulating alkaline phosphatase activity, both observed in all affected individuals. Infants typically present with signs of rickets and skeletal hypomineralization shortly after birth. Not all individuals experience all features, and severity varies considerably, which underscores the need for individualized assessment.

This condition is caused by pathogenic variants in the ALPL gene, which plays a critical role in bone mineralization. It is inherited in an autosomal recessive pattern, meaning an affected child must inherit two altered copies of the gene, one from each parent. Families are encouraged to consider genetic counseling to fully understand inheritance implications and family planning options.

Currently, management focuses on supportive care and symptom management, with treatment plans tailored to the individual. A multidisciplinary team approach is typically employed to address the diverse complications that may arise during the course of the condition. Patients should discuss treatment options with their healthcare team, and genetic counseling is recommended to help families understand the inheritable aspects of the condition.

Infantile hypophosphatasia is a lifelong condition with a highly variable course, where outcomes depend on factors such as symptom severity, age at diagnosis, and access to specialized care. With current standards of care, quality of life may be improved, although the condition can progress differently among individuals. Outcomes described in medical literature continue to evolve as standards of care improve. Families often find it helpful to connect with specialists familiar with this condition to guide ongoing management and future planning.

Clinical trials are underway exploring new treatment approaches for infantile hypophosphatasia. Individuals interested in clinical trials can search ClinicalTrials.gov or consult their care team about eligibility.