Review the following distinct clinical presentations of pediatric genetic syndromes. Match each patient's phenotypic description with the most appropriate underlying diagnosis.
- An infant presents with profound hypotonia and feeding difficulties shortly after birth, which transitions during early childhood into an insatiable appetite, rapid onset of obesity, and distinct almond-shaped eyes.Prader-Willi syndrome
- A toddler exhibits severe speech impairment, frequent inappropriate bouts of smiling and laughter, a jerky 'puppet-like' ataxic gait, and early-onset epilepsy.Angelman syndrome
- A preschool-aged child demonstrates an overly outgoing, highly verbal personality, accompanied by periorbital fullness, a stellate iris pattern, and echocardiographic evidence of supravalvular aortic stenosis.Williams syndrome
- An adolescent male is evaluated for intellectual disability, avoidant eye contact, prominent forehead and chin, large protruding ears, and bilateral macroorchidism.Fragile X syndrome
- A newborn is found to have tetralogy of Fallot, a cleft palate, facial dysmorphism, and experiences tetany in the first week of life due to severe hypocalcemia.DiGeorge syndrome (22q11.2 deletion syndrome)
Answer
The presentations map respectively to Prader-Willi syndrome, Angelman syndrome, Williams syndrome, Fragile X syndrome, and DiGeorge syndrome.
Each syndrome described has unique and highly testable phenotypic markers: Prader-Willi is marked by a biphasic feeding/weight pattern; Angelman by neurobehavioral features like spontaneous laughter and seizures; Williams by hypersociability and elastin-related vascular issues; Fragile X by characteristic physical traits like macroorchidism; and DiGeorge by developmental field defects affecting the pharyngeal pouches.
Step-by-Step Solution
Key Concept
Clinical diagnosis of pediatric genetic and microdeletion syndromes based on characteristic physical, behavioral, and metabolic phenotypes.