Coffin-Lowry syndrome is a rare syndromic form of X-linked mental retardation characterized by psychomotor retardation and growth retardation, and various skeletal anomalies. The clinical presentation of this condition shows a remarkable variability. Affected patients tend to have a characteristic facies, including microcephaly, large nose, anteverted nares, hypertelorism, down-slanting palpebral fissures, maxillary hypoplasia, frontal bossing, and high vaulted/narrow palate. Males show moderate to severe mental retardation and developmental delay. Skeletal abnormalities include a short stature and spinal curvature. Some patients may have seizures. Sensorineural hearing defects are seen in about 30% of the patients. About 15% also have mitral regurgitation. Affected females have a much less severe form of the disease, with moderate mental retardation in the worst cases.
Diagnosis of the condition in males is based on the presence of moderate-to-severe developmental delay, characteristic craniofacial and hand findings, and radiographic findings. Confirmation of the diagnosis requires the identification of mutations in the RPS6KA3 gene. Early diagnosis is important for proper management. Patients need to be followed up for potential hearing impairment, dental and ocular complications, and cardiac defects. Management is symptomatic. Seizures and drop attacks can be managed with the help of medications. Worsening kyposcoliosis may require surgical correction. Coffin-Lowry syndrome has an estimated incidence of 1:50,000 to 1:100,000.