deafness-genital anomalies-metacarpal and metatarsal synostosis syndrome

Deafness-genital anomalies-metacarpal and metatarsal synostosis syndrome is a very rare condition, affecting fewer than 1 in 1,000,000 people, that presents with sensorineural hearing impairment, skeletal anomalies of the hands and feet, and genital abnormalities such as hypospadias in males. The condition is also associated with distinct facial dysmorphism including a prominent forehead, ear anomalies, and facial asymmetry as well as cognitive challenges. It has been reported in only two unrelated patients, and thus, the full spectrum of clinical features and the natural history remain under investigation. Despite the absence of a clearly defined genetic basis, the condition is recognized by its consistent clinical presentation across multiple organ systems.

Individuals with this condition typically present with a combination of neurological, craniofacial, skeletal, and urogenital features. Neurologically, sensorineural hearing impairment and intellectual disability are prominent, contributing to challenges with cognitive development and communication, while an abnormal speech pattern may also be observed. Craniofacial features include facial asymmetry, a prominent forehead, and various ear anomalies—such as posteriorly rotated, low-set, and protruding ears—as well as abnormal nasal morphology and distinctive dermatoglyphics. Skeletal manifestations are marked by bilateral synostosis of the 4th and 5th metacarpals and metatarsals, with additional findings including short hallux, toe syndactyly, pes cavus, and other dysmorphic features. Genital anomalies, hypospadias in males, round out the multisystem presentation. Not all individuals experience every feature, and severity varies considerably.

The precise genetic basis of deafness-genital anomalies-metacarpal and metatarsal synostosis syndrome is not yet determined and is thought to involve complex genetic and environmental factors, given that no specific gene has been identified. Inheritance information is currently not available, and because the condition has only been described in two unrelated patients, its underlying mechanisms remain under investigation. Families are encouraged to seek genetic counseling for further clarification as advances in research may provide additional insights in the future.

Currently, management focuses on supportive care and symptom management for deafness-genital anomalies-metacarpal and metatarsal synostosis syndrome. Treatment is highly individualized and typically involves a multidisciplinary team that may include audiologists, developmental pediatricians, orthopedists, and urologists, among others. Long-term management includes regular surveillance to monitor for potential complications across multiple organ systems. Families are encouraged to discuss treatment options with their healthcare team and consider genetic counseling to help navigate complex care decisions.

Outcomes for individuals with deafness-genital anomalies-metacarpal and metatarsal synostosis syndrome vary considerably, and the overall clinical course is not uniformly predictable. With current standards of care, including comprehensive supportive management and timely intervention for specific complications, many individuals experience stabilization of symptoms following early challenges. Outcomes described in medical literature continue to evolve as standards of care improve, and with modern advances, quality of life has improved for many affected individuals. Families often find it helpful to connect with specialists familiar with the condition, as genetic counseling and support groups offer valuable guidance and community connections.