A 9-year-old child presents with pronounced horizontal bone loss in the anterior region and cementum defects. Urine analysis reveals the presence of phosphoethanolamine. What is the most likely diagnosis?

Explanation

The clinical features of early-onset bone loss combined with elevated urinary phosphoethanolamine indicate hypophosphatasia, a metabolic bone disease characterized by defective mineralization due to alkaline phosphatase deficiency. Other conditions like vitamin D resistant rickets, juvenile periodontitis, and osteomalacia do not typically present with increased phosphoethanolamine excretion.