Short stature, hands and feet, and brachycephaly. Distinct facies characterized by prominent mandible, small, broad nose with flat nasal bridge, and small mouth. Other abnormalities affect skin, genitals, teeth, and musculoskeletal system. Mental retardation is present in 90% of children and can be severe.
Acrodysostosis Syndrome; Maroteaux-Malamut Syndrome.
Chromosome studies have been normal. An autosomal dominant inheritance pattern has been described in two families. Sporadic cases have been described. The average parental age was slightly increased compared to the general parent population, which suggests advanced parental age is a risk factor for the condition.
Unknown. Some researchers consider the disorder to be a normocalcemic variant of pseudohypoparathyroidism.
Based on clinical features, with absence of endocrine abnormalities distinguishing it from pseudohypoparathyroidism. Epiphyseal stippling on radiologic examination is a constant finding in infancy.
The most common manifestations (present in >75% of patients) include mental retardation and/or learning difficulties, hypoplasia of the nose (short, broad nose with depressed nasal bridge) and the maxilla (often with prognathism), peripheral dysostosis, hyperplasia of the first ray of the foot, acromesomelic brachymelia, and decreased interpedicular distance of the vertebrae. A small mouth and marked hearing loss are other common findings. On radiologic examination advanced skeletal maturation is seen in combination with cone-shaped epiphyses, peripheral dysostosis, and abnormal metacarpophalangeal pattern profile. The hands and feet appear small secondary to shortening of the tubular bones. Poor growth results in brachymelic dwarfism.
Precautions before anesthesia
Mental retardation and hearing loss may make the management of these patients difficult. Sedative or anxiolytic premedication and the presence of the primary caregiver during induction may be helpful. Careful assessment of the airway in consideration of difficult airway management (hypoplastic maxilla, vertebral anomalies) is needed. Blood workup should include electrolytes, particularly calcium and phosphate levels to rule out pseudohypoparathyroidism.
Hypoplasia of the maxilla may lead to airway obstruction under anesthesia. Maintenance of spontaneous ventilation until the airway has been secured is recommended. Significant restrictions of hands, feet, and spine mobility may make positioning difficult and requires careful padding.
Avoid neuromuscular blockers until the airway has been secured.
Other condition to be considered
☞Albright Hereditary Osteodystrophy: Syndrome presenting with round face, short stature, short neck, and obesity. Subcutaneous and intracranial calcifications, seizures, and neuromuscular problems such as fatigue and muscle cramps. Pseudohypoparathyroidism and hypocalcemia.
WB: Acrodysostosis: Report of a 13-year-old boy with review of literature and metacarpophalangeal pattern profile analysis. Am J Med Genet