For example, a child may be delayed in speech (i.e., unable to produce intelligible speech sounds), but not delayed in language because they use a Sign Language. Additionally, language delay encompasses the entirety of language developmental progress being slowed and not just the speech aspects. Language delays are recognized by comparing language development of children to recognized developmental milestones. They are presented in a variety of ways, as every individual child has a unique set of language skills and deficiencies that are identifiable through many different screenings and tools. There are different causes leading to language delay; it is often a result of another developmental disorder and treatment requires analysis of the unique individual causes. The condition is frequently observed early on, among two- and three-year-olds. Early language delays are only considered risk-factors in leading to more severe language disorders. Language Development
The anatomical language centers of the brain are the Brocas and Wernickes area. These two areas include all aspects of the development of language. The Brocas area is the motor portion of language at the left posterior inferior frontal gyrus and involves speech production. The Wernickes area is the sensory portion of language at the posterior part of the left superior temporal gyrus and involves auditory verbal comprehension.There are recognizable speech and language developmental milestones in children. For children with language delays, milestones in their language development may be different or slowed. Recent studies have shown the different milestones for children with language delay compared to children with normal language development.
Sly syndrome, also called mucopolysaccharidosis type VII (MPS-VII), is an autosomal recessive lysosomal storage disease caused by a deficiency of the enzyme β-glucuronidase. This enzyme is responsible for breaking down large sugar molecules called glycosaminoglycans (AKA GAGs, or mucopolysaccharides). The inability to break down GAGs leads to a buildup in many tissues and organs of the body. The severity of the disease can vary widely. Signs and symptoms
The most severe cases of Sly syndrome can result in hydrops fetalis, which results in fetal death or death soon after birth. Some people with Sly syndrome may begin to have symptoms in early childhood. Symptoms can include an enlarged head, fluid buildup in the brain, coarse facial features, enlarged tongue, enlarged liver, enlarged spleen, problems with the heart valves, and abdominal hernias. People with Sly syndrome may also suffer from sleep apnea, frequent lung infections, and problems with vision secondary to cloudy corneas. Sly syndrome causes various musculoskeletal abnormalities that worsen with age. These can include short stature, joint deformities, dysostosis multiplex, spinal stenosis, and carpal tunnel syndrome.While some individuals have developmental delay, others may have normal intelligence. However, the accumulation of GAGs in the brain usually leads to the slowing of development from ages 1–3, and then a loss of previously learned skills until death. Genetics
The defective gene responsible for Sly syndrome is located on chromosome 7. Diagnosis
Most people with Sly disease will have elevated levels of GAGs seen in the urine. A confirmatory test is necessary for diagnosis.