Infantile neuroaxonal dystrophy is a rare pervasive developmental disorder that primarily affects the nervous system. Individuals with infantile neuroaxonal dystrophy typically do not have any symptoms at birth, but between the ages of about 6 and 18 months they begin to experience delays in acquiring new motor and intellectual skills, such as crawling or beginning to speak. Eventually they lose previously acquired skills. Cause
This condition is inherited in an autosomal recessive pattern, which means two copies of the gene (PLA2G6)  in each cell are altered. Most often, the parents of an individual with an autosomal recessive disorder each carry one copy of the altered gene but do not show signs and symptoms of the disorder. Pathophysiology
Mutations in the PLA2G6 gene have been identified in most individuals with infantile neuroaxonal dystrophy. The PLA2G6 gene provides instructions for making an enzyme called an A2 phospholipase. This enzyme family is involved in metabolizing phospholipids. Phospholipid metabolism is important for many body processes, including helping to keep the cell membrane intact and functioning properly. Specifically, the A2 phospholipase produced from the PLA2G6 gene, sometimes called PLA2 group VI, helps to regulate the levels of a compound called phosphatidylcholine, which is abundant in the cell membrane.Mutations in the PLA2G6 gene impair the function of the PLA2 group VI enzyme. This impairment of enzyme function may disrupt cell membrane maintenance and contribute to the development of spheroid bodies in the nerve axons.
Congenital syphilis is syphilis present in utero and at birth, and occurs when a child is born to a mother with syphilis. Untreated early syphilis infections results in a high risk of poor pregnancy outcomes, including saddle nose, lower extremity abnormalities, miscarriages, premature births, stillbirths, or death in newborns. Some infants with congenital syphilis have symptoms at birth, but many develop symptoms later. Symptoms may include rash, fever, an enlarged liver and spleen, and skeletal abnormalities. Newborns will typically not develop a primary syphilitic chancre but may present with signs of secondary syphilis (i.e. generalized body rash). Often these babies will develop syphilitic rhinitis ("snuffles"), the mucus from which is laden with the T. pallidum bacterium, and therefore highly infectious. If a baby with congenital syphilis is not treated early, damage to the bones, teeth, eyes, ears, and brain can occur. Classification
Early
This is a subset of cases of congenital syphilis. Newborns may be asymptomatic and are only identified on routine prenatal screening. If not identified and treated, these newborns develop poor feeding and runny nose. By definition, early congenital syphilis occurs in children between 0 and 2 years old. After, they can develop late congenital syphilis. Late
Late congenital syphilis is a subset of cases of congenital syphilis.