Hartsfield syndrome

Hartsfield syndrome is a rare condition characterized by holoprosencephaly, which is an abnormality of brain development, and a malformation of the hands and feet called ectrodactyly.

During early development before birth, the brain normally divides into two halves, the right and left hemispheres. Holoprosencephaly occurs when the brain fails to divide properly. In the most severe forms of holoprosencephaly, the brain does not divide at all. These affected individuals have one central eye (cyclopia) and a tubular nasal structure (proboscis) located above the eye. Most babies with severe holoprosencephaly die before birth or soon after. In less severe cases of holoprosencephaly, the brain is partially divided. The life expectancy of these affected individuals depends on the severity of signs and symptoms.

People with Hartsfield syndrome often have other brain abnormalities associated with holoprosencephaly. Affected individuals may have a malfunctioning pituitary, which is a gland located at the base of the brain that produces several hormones. Because pituitary dysfunction leads to the partial or complete absence of these hormones, it can cause a variety of disorders. These include diabetes insipidus, which disrupts the balance between fluid intake and urine excretion; a shortage (deficiency) of growth hormone, leading to slow or delayed growth; and hypogonadotropic hypogonadism, which affects the production of hormones that direct sexual development. Dysfunction in other parts of the brain can cause seizures, feeding difficulties, and problems regulating body temperature and sleep patterns. People with Hartsfield syndrome have delayed development that ranges from mild to severe.

The other hallmark feature of Hartsfield syndrome is ectrodactyly. Ectrodactyly is a deep split in the hands, feet, or both, with missing fingers or toes and partial fusion of the remaining digits. It can affect the hands and feet on one or both sides. Other features that have been described in people with Hartsfield syndrome include premature fusion of certain bones of the skull (craniosynostosis), heart defects, abnormalities of the bones of the spine (vertebrae), and abnormal genitalia. Some affected individuals have distinctive facial features, including eyes that are widely spaced (hypertelorism) or closely spaced (hypotelorism), ears that are abnormally small or unusually shaped, and a split in the lip (cleft lip) with or without an opening in the roof of the mouth (cleft palate).