7.0 Related Conditions

7.1 Introduction

There are many conditions that are associated with autistic spectrum disorders. The purpose of this part of About Autism is to highlight some of the common ones and, where possible, link people to societies, groups or further information resources that can provide additional support.

It is important to note that all children at some stage in development may exhibit behavior that is similar to that seen in a person with autism. Temper tantrums, late speech development, arm flapping when excited, food fads etc are all part of many people's early development. However, the person with autism has a triad of impairments which must all be present for diagnosis: impairments of social interaction, communication and imagination.

The triad cannot be explained away by another disability. Thus the following associated conditions are in addition to the diagnosis of autism, not a replacement for it.

7.2 Learning difficulties

When considering the whole spectrum of autism including Asperger's syndrome about one third have additional learning difficulties. Most diagnosed with Asperger's have IQ's in the low average or better range. Of those with Kanner syndrome, about two-thirds have severe to mild difficulties and one third are in the low average or better range.

7.3 Rett's syndrome

Rett syndrome is a neurological disorder generally supposed to occur only in girls, in which individuals exhibit reduced muscle tone, autistic-like behavior, stereotyped hand movements consisting mainly of wringing and waving, loss of purposeful use of the hands, diminished ability to express feelings, avoidance of eye contact, a lag in brain and head growth, gait abnormalities and seizures. Hypotonia (loss of muscle tone) is usually the first symptom.

The syndrome was first recognized in 1966 by Dr. Andreas Rett, however it was not until a paper was published by Dr. Bengt Hagberg in 1983 that the disorder was made widely known in medical circles. The syndrome affects approximately 1 in every 10,000-15,000 live female births, with symptoms usually appearing in early childhood. The cause of Rett's syndrome is unknown.

7.3.1 Diagnosis

At present, diagnosis depends on observation of a child's early growth and development and on an ongoing assessment of medical history and physical and neurological status. In the case of an adult a review of the same would apply.

As yet, there are no laboratory tests which can confirm the clinical diagnosis. A paediatric neurologist and/or a developmental paediatrician should be consulted for confirmation.

Essential criteria for diagnosis include:

1. Apparently normal pregnancy and delivery, with development of voluntary movements until between 6-18 months.
2. Normal head circumference at birth followed by a slowing of head growth between 6-48 months.
3. Unexplained loss of acquired purposeful hand skills between the ages of 5-30 months accompanied by communication malfunction and social withdrawal.
4. Development of severely impaired speech and understanding of language accompanied by severe retardation of intellectual development.
5. Loss of learned behavioral, social and voluntary motor skills.
6. A fixed pattern of hand movements such as wringing, squeezing, clapping, tapping, washing, rubbing and mouthing, which can become almost constant while awake. Pattern appears after loss of purposeful hand skills.
7. Appearance between 1-4 years of a shuffling or jerky gait with fixing or locking of joints into one position so reducing the ability to move from one position to another. (Only about half of the girls with this syndrome are ever able to walk independently in order to show this criterion).
8. Shakiness of the torso, and also of the limbs, when the child is upset or agitated.
9. Diagnosis usually tentative until 2-5 years of age.

7.4 Fragile X syndrome

Fragile X syndrome (FXS) is now the most common known inherited cause of developmental disabilities, but was not discovered until the late 1970s. By 1980 it was found that people showing certain mental and physical characteristics had a chromosomal abnormality caused by a partial break on an X chromosome, called a 'fragile site'. In 1991 the Fragile X gene was identified within this site.

The spectrum of Fragile X syndrome ranges from normal development to developmental delay, learning disabilities, mild to severe intellectual disability, autistic-like behavior and attentional problems. The majority of children are mildly to moderately affected.

Genetic testing has changed the approach to the diagnosis of the condition because there is now a reliable and relatively simple blood detection test which is available to all children with developmental delay of unknown cause.

7.4.1 Incidence

Estimates suggest about 1 in 4,000 males are affected and that about 1 in 1,000 females carry the gene. Many affected family members are unaware of the genetic cause and have yet to be diagnosed.

7.4.2 Diagnosis

The clinical features of Fragile X syndrome include physical, developmental and behavioral characteristics and range from normal through mild to severe in presentation. Intellectual disability (IQ less than 70) is present in 80% of males and 50% of females. Children may have been labeled as having pervasive developmental disorder, Asperger's syndrome, autistic spectrum disorder, learning disability or developmental delay.

Physical, developmental and behavioral characteristics include:

Physical

The classic features include:

• Elongated face with prominent jaw, which is more obvious after puberty.
• Prominent, large ears.
• High arched palate.
• Large testicles, which are mainly seen after puberty.
• Recurrent ear infections.
• Connective tissue problems, such as flat feet, loose joints, congenital hip dislocation, scoliosis.
• Mitral valve prolapse.
• Seizures, including 'absences' or petit mal.
• Eye problems, such as strabismus or squint.

Developmental

• Attention deficit in at least 80%, may be without hyperactivity.
• Autistic-like features (e.g. hand flapping and biting, gaze aversion, preoccupation with objects).
• Difficulty adjusting to change.
• Social anxiety.
• Jocular, litanic speech.
• Speech perseveration and echolalia (repetition of words or phrases).
• Shyness.
• Anxiety / hyperarousal.
• Sensory defensiveness (aversion to loud noise, touch, strong smells, eye contact).
• Mood instability with aggression, depression (particularly in adolescence).

The diagnosis of Fragile X syndrome is made on a blood sample tested for analysis of the FMR1 gene. This DNA testing has been available since 1991 to detect Fragile X in normal carriers (male and female) and in affected children. This test cannot determine the degree of intellectual disability.

For further support contact:

The US based National Fragile X Foundation - http://www.nfxf.org/

7.5 Landau-Kleffner syndrome

Landau-Kleffner Syndrome is also known as Acquired Epileptic Aphasia in Childhood. Most children first show signs of this syndrome somewhere between the age of three and nine years old. Prior to this they have usually grown and developed normally with no sign of a seizure.

7.5.1 Symptoms

The first sign of difficulty usually appears in the form of difficulty with communicating with speech and language. They show not only difficulty understanding what is said to them (a receptive dysphasia) but also have difficulty in putting their thoughts into words (an expressive dysphasia). Other aspects of learning are probably not affected. Seizures will appear in the majority of these children certainly within a few weeks of the first signs of the language difficulty. They take the form either of tonic clonic seizures which are probably partial in origin or complex partial seizures.

7.5.2 Diagnosis

An EEG (electroencephalogram) will show signs of a brain malfunction involving both cerebral hemispheres but usually the spike and wave activity seen on the EEG will be more prominent in the dominant cerebral hemisphere which deals with language function. For most people this will be on the left side.

The cause of the syndrome is not known. Twice as many boys than girls are affected which may mean that, for many, the problem results from some of the neural networks within the brain falling short of full development. In other children, the problem seems to be precipitated by a viral infection.

The long term outlook for most children with this condition is good. In the vast majority, the seizures will disappear by the time they are in their mid-teens. In half the children, the language difficulties will disappear within a few months or certainly the first year or two. In the remaining half, some improvement will occur in time. In perhaps 20 per cent, or one in five, of cases the children will keep their language difficulties.

For further support contact:

The British Epilepsy Association - http://www.epilepsy.org.uk/

7.6 Tuberous sclerosis

Tuberous Sclerosis (TS) is a genetic disorder that causes benign tumors to form in many different organs - primarily in the brain, eyes, heart, kidney, skin, and lungs. It is often first recognized because of two neurologic symptoms - epileptic seizures and varying degrees of learning difficulties. Many people with TS also have autism.

7.6.1 Incidence

The true prevalence of TS is unknown, but its incidence has recently been estimated to be 1 in 6,000 live births. TS occurs in both sexes and in all races and ethnic groups. TS is a genetic disease.

7.6.2 Diagnosis

All of the following tests are usually recommended at the time of diagnosis of TS, or if TS is suspected:

1. A thorough examination of the skin to detect any of the usual skin lesions of TS. This should include an examination with a Wood's lamp.
2. Dilation of the pupils with eye drops containing an atropine-like substance allows direct examination of the retina with the ophthalmoscope, and an ophthalmologist familiar with TS should do an indirect examination with a magnifying lens.
3. A CT or MRI of the brain should be done to look for TS brain lesions. A MRI should be done if possible so that the full aspect of the brain involvement in TS is documented.
4. An ultrasound, CT or MRI of the kidney should be done to document kidney involvement.
5. EEG and/or telemetry studies should be done if the child has seizures.
6. An echocardiogram (to detect cardiac rhabdomyomas) and an EKG of the heart should be done so that any heart involvement will be documented.

For further support contact:

The US National Tuberous Sclerosis Association - http://www.ntsa.org/

The UK Tuberous Sclerosis Association - http://ourworld.compuserve.com/homepages/tsassn/tsa.htm

7.7 Epilepsy

Epilepsy occurs in 30% of people with autism. In the UK 1 in 130 people has epilepsy - around 420,000 - making it the second most common neurological condition after migraine. It may take many forms from full-blown seizures to 'absence attacks', in which the person seems to 'blank out' for a few seconds or minutes.

There are over 40 different types of seizures. Each person will experience epilepsy in a way that is unique.

7.7.1 Diagnosis

It can be difficult for doctors to diagnose epilepsy. This is because there is no one certain test and there are many other possible reasons for the loss of consciousness. Most people with epilepsy don't recall what happened during a seizure. About one in 20 people has had an epileptic seizure at some time in their lives but not all develop epilepsy.

If a doctor suspects epilepsy she/he should refer the person to a doctor who specialises in brain disorders or in epilepsy itself. This specialist may order a number of painless tests to help decide whether the person has epilepsy and identify what type it is, these may include:

• An EEG (electroencephalogram). This test picks up the electrical activity of brain cells and transmits it to an instrument, which produces a printout of the brain waves. The test is performed whilst the patient opens and closes their eyes, breaths deeply and during exposure to a flashing light. The whole thing usually takes less than half an hour. The specialist may ask for more specialised types of EEG to help diagnose attacks of uncertain cause.
• Brain scans to look for any areas of damage to the brain that could account for the seizures. The most common type of scan is CT (computed tomography). X-rays are taken of the brain at different angles and passed through a computer to produce a picture of 'slices' of your brain.

A more sophisticated technique is MRI (magnetic resonance imaging). This provides a high-quality image of your brain - without using X-rays or other radiation. The drum-like scanner contains a powerful magnet that picks up signals from the brain. These are fed into a computer, which creates a 3-D image of the area being scanned and displays it on a screen.

A blood test is usually taken to check overall health and to look for any other conditions that could be responsible for seizures.

For further support contact:

The British Epilepsy Association ­ http://www.epilepsy.org.uk/

7.8 Deafness

Autistic disorders can occur with any degree of deafness in which case a dual diagnosis is important. Testing may be difficult so parental observations are very important as a part of diagnosis.