Yuan-Harel-Lupski syndrome

Yuan-Harel-Lupski (YUHAL) syndrome is a rare neurological condition that has a combination of features of two other disorders, Potocki-Lupski syndrome and type 1A Charcot-Marie-Tooth disease.

The first signs and symptoms of YUHAL syndrome begin in infancy. Infants with YUHAL syndrome usually have weak muscle tone (hypotonia), which may lead to feeding problems. They typically do not grow and gain weight at the expected rate. Babies and children with YUHAL syndrome have delayed development, including delayed speech and language skills and motor skills such as walking. YUHAL syndrome is also associated with behavioral difficulties. Many affected individuals have sleep problems, including pauses in breathing during sleep (sleep apnea) or trouble falling asleep and staying asleep. Some people with YUHAL syndrome have subtle differences in facial features, including outside corners of the eyes that point downward (down-slanting palpebral fissures), a triangular face, and eyes that do not look in the same direction (strabismus). These signs and symptoms are similar to those of Potocki-Lupski syndrome.

Other signs and symptoms of YUHAL syndrome begin in childhood and result from damage to peripheral nerves, which connect the brain and spinal cord to muscles and to sensory cells that detect sensations such as touch, pain, and heat. Damage to peripheral nerves can lead to loss of sensation and wasting (atrophy) of muscles in the legs. Children with YUHAL syndrome often develop muscle weakness, particularly in the lower legs, which may lead to an unusual walking style (gait). Some affected individuals have foot abnormalities such as flat feet (pes planus), high arches (pes cavus), or an inward- and upward-turning foot (clubfoot). They may also experience reduced reflexes and a decreased sensitivity to touch, heat, and cold in the feet and lower legs. Similar features are seen in individuals with type 1A Charcot-Marie-Tooth disease, although they may appear earlier in people with YUHAL syndrome, often before age 5.

Abnormal development of other tissues and organs, such as the heart or kidneys, can occur in YUHAL syndrome.