A 5-year-old boy is brought in due to persistent nighttime bedwetting and loose first deciduous molars on both sides. His mother reports that he frequently wakes up multiple times at night to drink water. What is the most probable diagnosis?

Explanation

The combination of chronic bedwetting, loose deciduous molars, and increased thirst at night suggests Hand-Schüller-Christian disease, a form of Langerhans cell histiocytosis characterized by bone lesions and diabetes insipidus. Other options like osteopetrosis, Niemann-Pick disease, and fibrous dysplasia do not typically present with these symptoms.