Bibliographic record
Abstract
A 12-year-old boy with autism spectrum disorder (ASD), moderate intellectual disability and seizures initially exhibited symptoms of hyperactivity, irritability and obsessive behaviour. He was managed with 7.5 mg methylphenidate orally three times per day, 0.5 mg risperidone orally two times per day and 350 mg valproic acid orally two times per day with good initial response. He subsequently exhibited sudden onset of negative self-talk and crying episodes with no identifiable triggers. Over the following six months, he gradually developed urinary incontinence, slowing of motor function and decreased speech. He required verbal and physical prompts to complete a task; however, his symptoms of anxiety, hyperactivity and irritability abated. There was no history of illness or stressful life events. Clinically, he was mute and exhibited posturing movements. On physical examination, no neurological deficits or autonomic dysfunction were identified. Investigations, including an ophthalmological examination for Kayser-Fleisher rings, electroencephalogram, urine culture, complete blood count, thyroid, liver and renal function tests, ceruloplasmin and vitamin B12 levels, were normal. A drug screen only revealed risperidone and valproic acid metabolites. A trial of 2 mg lorazepam was ineffective. His medications were then weaned and discontinued, and his diagnosis became clear. Initially the patient had waxy flexibility (slight resistance to positioning by the examiner), echopraxia (imitation of examiners’ movement) and experienced freezing while eating, walking and toileting. Discontinuation of his antipsychotic and stimulant medication resulted in a slow resolution of his catatonic symptoms. His findings were consistent with catatonia in ASD, although waxy flexibility is uncommon in the ASD population. Catatonia is a clinical psychiatric presentation that may be acute or surreptitious in development. There are no biological markers for catatonia. Its presentation in ASD is ambiguous due to overlapping symptomatology and nosology. Catatonia is typified by the presence of ≥3 of the following manifestations: stupor; catalepsy; waxy flexibility; mutism; negativism; posturing; mannerism; stereotypy; agitation; grimacing; and echopraxia (1). Reported clinical presentation of catatonia in the context of ASD includes regression in motor or speech skills (2). The prevalence of catatonia among youth and adults with ASD has been reported to be as high as 17%, which is greater than the 0.6% to 10% reported in the non-ASD psychiatric population (2,3). However, selection bias and retrospective study designs make the true prevalence rate unclear. Presentation of catatonia is most common between 10 and 19 years of age; in 50% of subjects, catatonia is preceded by behavioural disturbance, such as aggression, and 43% experience some emotional event. Catatonia is characterized not only by the number of symptoms but in the substantial deterioration in clinical presentation and function from baseline. The etiology of catatonia is believed to involve neurochemical pathways involving dopamine blockade, glutamate hyperactivity and relative gamma-amino butyric acid (GABA) deficit. GABA acts inversely with glutamate and, when there is an excess of glutamate, GABA will suppress its release. This gives credence to the effectiveness of benzodiazepine (GABA agonist) in its management (4). Genetic linkage studies have shown potential association with ASD, catatonia and GABA receptors on chromosome 15q (5). Catatonia is associated with antipsychotic medications and other dopamine modulators. With the increased use of pharmacotherapy in the ASD population to manage irritability, it is imperative for physicians to recognize the presentation of catatonia and initiate management swiftly. Catatonia can be acute in onset, such as in the associated autonomic dysfunction ‘malignant catatonia’, which should be considered a medical emergency because it is associated with a 10% to 20% mortality rate (6). There are no ASD-specific rating scales for the assessment of catatonia. The first-line management of catatonia is to discontinue precipitants such as antipsychotics. Historically, benzodiazepines, mainly lorazepam, are used as first-line pharmacotherapy for the management of catatonia in ASD. There are no randomized controlled trials evaluating pharmacotherapy options in this population. Management is based on data from case reports/series. A trial of 1 mg to 2 mg lorazepam orally or parentally is recommended. If there is improvement in catatonic symptoms, one should consider increasing the lorazepam dose. A maximum dose of 24 mg per day has been reported (7). Improvement is anticipated within one to two weeks. Long-term therapy for up to 12 months has been suggested with a tapering regimen. Electroconvulsive therapy is usually indicated for severe catatonia in adults; however, its true efficacy and effectiveness to treat catatonia in ASD is unknown. Current evidence for its use is limited to case reports. With the increased prevalence of ASD and use of antipsychotic medication among this population, recognition of catatonia and prompt management is essential. A team approach is recommended. Catatonia in ASD commonly presents during adolescence with regression of motor and speech skills. The potential cause is an imbalance in glutamate (high) and dopamine (low) and, therefore, discontinuation of antipsychotics and initiation of benzodiazepines is recommended. Consider autoimmune, infectious, recreational drug exposure and metabolic etiologies when encountering this presentation.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.009 |
| Meta-epidemiology (narrow) | 0.003 | 0.002 |
| Meta-epidemiology (broad) | 0.002 | 0.003 |
| Bibliometrics | 0.005 | 0.002 |
| Science and technology studies | 0.006 | 0.003 |
| Scholarly communication | 0.003 | 0.002 |
| Open science | 0.004 | 0.004 |
| Research integrity | 0.015 | 0.011 |
| Insufficient payload (model declined to judge) | 0.005 | 0.002 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".