Brachydactyly is believed to be largely due to abnormalities arising from the bones inside the hands and feet, specifically the metacarpals and metatarsals. Craniofacial abnormalities
Furthermore, most people with Filippi Syndrome exhibit craniofacial abnormalities. Craniofacial abnormalities are birth defects observed at the head or face region of affected individuals. Some of the craniofacial abnormalities present in people with Filippi Syndrome include microcephaly (having a skull that is smaller than normal), prominent/ elevated nasal bridge, hypertelorism (having ones pair of eyes further apart from each other than normal), and underdeveloped nasal alae (underdeveloped tissues surrounding the nostril). Less common craniofacial abnormalities include having a broad forehead, thin vermilion border (having a thin upper lip), and frontal hirsutism (having a hairy forehead). Mental retardation
People with Filippi Syndrome may also demonstrate varying degrees of intellectual disability. Affected individuals may experience defective speech development, aphasia (experiencing difficulty in finding the appropriate words to use), vision impairment, and an inability to speak. Growth retardation
Another characteristic symptom of people with Filippi Syndrome is the occurrence of growth retardation, which is also referred to as growth delay. Such growth delays may be either prenatal or postnatal, meaning that they can occur both before and after birth. In particular, delayed bone maturation can be observed in patients with Filippi Syndrome. Other symptoms
People with Filippi Syndrome may exhibit some other physical abnormalities.
Under normal conditions, the neurons forming a germinal layer around ventricles migrate to the surface of the brain and form the cerebral cortex and basal ganglia. If this process is abnormal or disturbed it could result in the enlargement of the occipital horns of the lateral ventricles. Common prenatal disturbances that have been shown to disturb the neuronal migration process include the following:
continuation of oral contraceptives
exposure to alcohol
intrauterine malnutrition
intrauterine infections such as toxoplasmosis
maternal drug ingestion during early pregnancy such as corticosteroids, salbutamol, and theophyllineResearchers also believe that these factors can cause destruction of neural elements that have previously been normally formed.It is suggested that the underdevelopment or lack of white matter in the developing fetus could be a cause of colpocephaly. The partial or complete absence of white matter, also known as agenesis of the corpus callosum results in anatomic malformations that can lead to colpocephaly. This starts to occur around the middle of the second month to the fifth month of pregnancy. The lateral ventricles are formed as large cavities of the telencephalic vesicle. The size of the ventricles are decreased in normal development after the formation of the Foramen of Magendie, which decompresses the ventricular cavities. Myelination of the ventricular walls and association fibers of the corpus callosum and the calcarine fissure helps shape the occipital horns. In cases where this developmental process is interrupted, occipital horns are disproportionately enlarged.Colpocephaly has been associated with chromosomal abnormalities such as trisomy 8 mosaic and trisomy 9 mosaic.