Hypertonia is one of the most common signs of Rett syndrome. It is distinguished by an increase in muscle tension and the loss of stretching ability in a muscle. Hypertonia can cause rigidity and muscle spasms and eventually lead to a loss of muscle function and deformity.
Loss of Speech
Children with Rett syndrome generally start to show a loss of language skills around the age of one or two. Children will have started to babble and talk normally, only to have those skills leave them within a matter of weeks or months. Some children may retain the ability to "mand" – or request desired items, while others will lose language completely and need to communicate via pictures or sign language.
Loss of Motor Skills
Another sign of Rett syndrome is the loss of both fine and gross motor skills. Around the age of six to eight months of age, babies will have a delay or regression in sitting up; this is the first indication of a problem. Loss of fine motor skills relates to grasping, reaching and holding a toy or spoon. Loss of gross motor skills concerns walking, lifting and throwing. These skills will either rapidly disappear or never evolve in the first place for a child with Retts.
Slowed Head Growth
Around the same time children are losing their gross and fine motor skills, parents or doctors may notice a slowed growth of the child's head. Children with Rett syndrome have slower than normal brain growth, resulting in a smaller than normal head circumference. As children with the disorder age, there is delayed growth of other body parts as well, affecting movement and coordination.
Seizures occur in about 80 percent of children with Rett syndrome. Seizures are most commonly seen in children aged seven to twelve, usually those with severe early developmental problems and delays. There are two types of seizures a person might experience – focal seizures and generalized seizures. A focal seizure is also known as a partial seizure and affects only one part of the brain. This type of seizure has minimal convulsing and shaking. A generalized seizure affects both sides of the brain, usually resulting in the convulsing and shaking that people typically associate with a seizure.
Diminished Eye Contact
Babies love to look at people. Another definite sign of Rett syndrome is the lack of or loss of eye contact in your child. Loss of eye contact can usually be observed in a child by the age of 18 months, although it may be noticed as early as six months of age. Children will generally look through you or seem to be staring off into space. Eventually they will stop responding to verbal prompts to look at a person. Eye contact does tend to improve if a child enters Stage IV of Rett syndrome.
Almost every child on the autism engages in self-stimulatory behaviors. Typical behaviors include visual stimming – staring at lights, blinking, twisting or turning a toy in a child's field of vision, or lining up objects and looking at them; auditory – humming, moaning or echolalic speech; tactile – touching objects or holding an object in their hand; and other types of stimulation, such as rocking, licking objects or sniffing and smelling people or things.
Apraxia is perhaps the most severely disabling feature of Rett syndrome, interfering with every body movement, including eye gaze and speech. Once affected with apraxia – in Stage IV of Retts – a person is unable to correctly use any of their muscle functions. They might try to speak only to have the words come out slurred or garbled. They may want to move their hand but be unable to do so. Other ways apraxia affects a person is by confusing the order of tasks (a person will put on a coat before a shirt) or the inability to use objects for their intended purpose (using a spoon as a pen or vice versa).
Other Problems and Concerns
There are other things to look for that occur as a result of being diagnosed with Rett syndrome. Eighty percent of girls with the disorder end up developing scoliosis – curving of the spine that can result in pain and restricted mobility. Many girls will also suffer from constipation or other gastrointestinal problems, such as acid reflux. In addition heart problems characterize this disorder, mainly concerning the heartbeat's rhythm. As the disease progress, children have trouble feeding and dressing themselves, trouble with swallowing or chewing and difficulties with sleep at night, leading to an increase in the amount of time spent sleeping during the daytime hours.
PubMedHealth: Apraxia. http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0004944/
PubMed.gov: Seizures in Rett Syndrome: An Overview from a one-year calendar study. http://www.ncbi.nlm.nih.gov/pubmed/17433737
Medline Plus: Seizures. http://www.nlm.nih.gov/medlineplus/seizures.html
North Shore Pediatric Therapy: Self Stimulatory Behaviors (A.K.A. Stimming). http://nspt4kids.com/health-topics-conditions/self-stimulatory-behaviors/
National Institute of Neurological Disorders and Stroke: NINDS Hypertonia Information Page. http://www.ninds.nih.gov/disorders/hypertonia/hypertonia.htm
Mayo Clinic: Rett Syndrome. http://www.mayoclinic.com/health/rett-syndrome/DS00716/DSECTION=symptoms
Author’s Own Experience