Diagnostic Challenge and Management Dilemma of William Syndrome: A Case Report

Facial dysmorphism can be a manifestation of different congenital syndromes. However, diagnosing them remains a challenge. William syndrome is a relatively rare genetic multi-system disorder occurring due to a microdeletion on the chromosomal locus 7q11.23. Herein, a case of a 13-year-old child is being reported, who presented with complaints of delayed attainment of developmental milestones, syndromic facies, intellectual delay, poor scholastic performance and unclear speech. Fluorescent InSitu Hybridisation (FISH) confirmed the diagnosis. Treatment was started with a multidisciplinary approach, including behavioural counselling, genetic counselling, occupational therapy and treating the electrolyte disturbances. After detailed counselling and discussion with the parents as well as the child, the child is doing fine and improving in various domains of life. The quality of life of the child seems to be improving. Uniquely, this child had persistent learning difficulties with an IQ score of 73.8, mild corpus callosum stenosis on Magnetic Resonance Imaging (MRI), and a rare finding of transient asymptomatic hypercalcaemia (14.3 mg/ dL) in adolescence, which is most reported in infancy. The child had no cardiovascular involvement, such as supravalvular aortic stenosis, which is typically seen in 70-80% of cases. This case underscores the expanding neurodevelopmental and biochemical phenotype of Williams syndrome. Recent studies also stress the role of early neuropsychological assessments, ongoing cardiac surveillance and individualised learning strategies for long-term outcomes.