Childhood Disintegrative Disorder (Heller’s Syndrome)

Childhood Disintegrative Disorder

Childhood disintegrative disorder (CDD), also called Heller’s syndrome or disintegrative psychosis, is a rare mental disorder characterized by the reversal of language, social function and motor skills after the onset of late developmental delays. It has been difficult for researchers to determine what causes the disorder.

There are some similarities between CDD and autism, and it’s sometimes considered a lower-functioning form. CDD and other subtypes of PDD (Asperger’s syndrome, autism, and PDD-NOS) were combined in May 2013 under the Department of Health and Human Services’ new DSM-5 manual as “autism spectrum disorder.”

A diagnosis of CDD was originally made 35 years before autism by the Austrian educator Theodor Heller (1869-1938). The syndrome was previously called dementia infantilis by Heller.

The development of skills usually regresses after a period of relatively normal development. It usually occurs after three years of normal development, but the age at which this regression can occur varies.

It is perfectly normal for a child to take notice of his or her regression, and may even ask at first, verbally, what is going on. The most obvious symptom of children who have hallucinations is that skills that they have apparently mastered are lost or deteriorated over time.

Most children with autism are already a little behind when the disorder becomes apparent, but there are some signs in young children that might not be obvious. Many writers have described this as a devastating condition that affects the individual and their family.

It is widely recognized that there is considerable debate about the best treatment for CDD, as there is with all other categories of pervasive developmental disorders.

Related: Learning Disorder

Causes of childhood disintegrative disorder

It is unknown what caused the problem. CDD occurs when previously normally developing children seem to regress, sometimes rapidly. In general, the condition evolves in a short period of time or overtime, and onset is usually in the fourth year of life, though some variations are possible.

The condition has been referred to as childhood dementia by some, suggesting that brain depositions of amyloid are the cause. However, pathophysiology has yet to be established.

The onset of CDD can also be linked to certain other conditions, especially if it occurs later in life:

  • Lipid storage diseases: An excess accumulation of fats (lipids) is evident in the brain and nervous system as a result of this condition.
  • Subacute sclerosing panencephalitis: It occurs when a form of the measles virus infects the brain over time. Nerve cells die as a result of brain inflammation in this condition.
  • Tuberous sclerosis (TSC): TSC is a genetic condition. It can develop tumors in the brain as well as other organs like the kidneys, lungs, heart and eyes. Hamartomas are noncancerous (benign) tumors that develop in the brain.
  • Leukodystrophy: The white matter in the brain eventually fails because the myelin sheath does not develop properly.

Read: Intellectual Development Disorder

Childhood disintegrative disorder symptoms

Children who have been affected show clinically significant loss of earlier acquired skills in at least two of the following areas:

  • Having an expressive language style
  • Receptive language skills
  • Self-care skills and social skills
  • Bowel or bladder control
  • Play skills
  • Motor skills
  • The following two functions are also abnormal:
  • Social interaction
  • Communication
  • Repeated behaviors or interests

It has been at least two years since the child appeared to be developing normally. Between the ages of 3 and 4 years, the change is generally discernible but may occur as early as 10 years of age.

  • An abrupt or gradual onset is possible.
  • Children may become aware of the regression themselves and may ask what is happening to them.
  • Parents and professionals often do not observe abnormalities in language and other non-verbal communication, play, behavioral adaptation and emotional development.
  • Children who can speak in two- or three-word phrases lose this ability. Over time, they would cease to speak altogether or only retain fragments of what they had previously said.
  • A child can experience social and emotional issues, such as becoming afraid of physical contact if he or she was once happy to be cuddled.
  • Hallucinations are sometimes described by or appear to be being experienced by children.

Read: Developmental Coordination Disorder

Comparison with autism

Eventually, the patient displays social and communication issues similar to those associated with severe autism or Kanner’s syndrome. However, it differs from autism due to the normal developmental history that preceded it.

There is a higher probability that CDD children will exhibit fearfulness and early stereotypic behaviors than autistic children.

Childhood developmental disorders cause more epilepsy than autism.

When compared with autism, children with CDD appear to have a more even degree of intellectual impairment, although the overall degree and outcome are similar in both groups.

Signs of CDD

There are not many specific signs that indicate the presence of the condition, and physical abnormalities are rare, although minor abnormalities like microcephaly or motor incoordination may be found.

The patient should undergo a thorough examination of their CNS including fundoscopy to rule out other causes of their symptoms.

Read: Global Developmental Delay

CDD diagnosis

This differential diagnosis also requires consideration of these other pervasive developmental disorders, such as Rett’s syndrome, autistic spectrum disorder, pervasive developmental disorder – not otherwise specified (PDD-NOS), and general learning disabilities. You need to rule out the following conditions:

  • Mercury poisoning
  • Lead poisoning
  • Aminoacidurias
  • Hypothyroidism
  • Brain tumor
  • Organophosphate exposure
  • Atypical seizure disorder
  • HIV infection
  • Creutzfeldt-Jacob disease/new variant CJD
  • Another rare metabolic/neurodegenerative condition is glycogen storage disorders
  • Childhood schizophrenia
  • Subacute sclerosing panencephalitis (SSPE)
  • Tuberous sclerosis


A diagnosis of the condition should exclude reversible causes:

  • FBC
  • U&E/glucose
  • LFT
  • TFT
  • Heavy metal levels
  • HIV testing
  • Urine screening for aminoaciduria
  • Neuroimaging studies

A secondary care provider usually conducts these tests during the initial assessment. A brain scan, MRI, or electroencephalogram (EEG) may be used to confirm that an alternative diagnosis was not overlooked.

Read: Alice in Wonderland Syndrome

Treatment of CDD

Language loss and skills related to self-care and social interaction are serious issues. There are some ongoing disabilities among the affected children, which require long-term care. There are several types of treatment for CDD, including behavior therapy, environmental therapy, and medication.

The treatment is tailored to each child’s disability, needs, and educational goals, as with autism. The following may be included:

  • Behavior therapies, such as applied behavior analysis, aim to teach the child systematic knowledge of the language, self-care and social skills.
  • Environment-based therapies, including sensory enrichment.
  • Medication:
    • Behavioral symptoms of PDD may be improved by risperidone. However, the specific efficacy of CDD treatments is unclear.
    • The use of other antipsychotics, stimulants, and selective serotonin reuptake inhibitors (SSRIs) to help in the control of problematic behavior, especially aggression, can also be effective when used by trained professionals. It is well-known that neuroleptic medications pose a large risk of developing the neuroleptic malignant syndrome.
    • Anti-epileptic medication may be required in cases of epilepsy.

Read: Attachment Disorder


  • It is common for loss of skills to plateau by around ten years of age. Some patients may see some, but very limited improvement.
  • Frequently, children with long-standing impairments in behavioral and cognitive functioning resemble children with severe autism (Kanner’s syndrome).
  • Symptoms include intellectual decline, self-sufficiency problems, and impairments of adaptive skills, most of which lead to severe intellectual disability.
  • Comorbid medical conditions such as epilepsy are common.
  • Mentally disabled individuals with a moderate-to-severe intellectual disability or with a difficulty communicating perform worse in school than those with an intellectual level and some verbal communication.
  • The outlook is poor. Support will be needed for children throughout their lives.
  • SSRIs and neuroleptics can relieve seizures and lower seizure thresholds during childhood and adolescence.
  • It was previously reported that life expectancy was normal. However, recent studies suggest that autistic range disorders are twice as likely to cause death as the general population due to epilepsy-related complications.

Read: Hysteria Disorder

Historical note

Childhood disintegrative disorder was described in 1908 by a Viennese remedial teacher, Theodor Heller, that six children, who had developed normally up to that point, suddenly developed a severe mental regression in their third and fourth years of life. It is also known as dementia infantilis. Dementia infantilis and infantile autism were first distinguished in 1943 by Leo Kanner as separate diagnoses.