Catatonia in Children Can Present Without Waxy Flexibility
Yes, catatonia in pediatric patients can absolutely present without waxing and waning flexible rigidity (waxy flexibility), as this is only one of multiple possible motor signs in the catatonic syndrome. 1
Understanding the Spectrum of Catatonic Motor Signs
Catatonia is defined as a syndrome of primarily psychomotor disturbances characterized by the occurrence of several different symptoms including stupor, catalepsy, waxy flexibility, mutism, negativism, posturing, mannerisms, stereotypies, psychomotor agitation, grimacing, echolalia, and echopraxia. 1 The key word here is "several"—not all signs need to be present for diagnosis.
The most common neurologic finding in catatonia is actually lead pipe rigidity, not waxy flexibility, though akinesia, dyskinesia, or waxy flexibility may be present. 1 This means waxy flexibility is an optional feature, not a required one.
Unique Presentations in Pediatric Populations
Children with Neurodevelopmental Disorders
Catatonia presents differently in children with neurodevelopmental disorders (NDD) such as autism spectrum disorder, Down syndrome, and Prader-Willi syndrome. 2 These presentations can be missed due to diagnostic overshadowing, where clinicians attribute new symptoms to the underlying neurodevelopmental condition rather than recognizing acute catatonic deterioration. 2, 3
The concept of "catatonic deterioration from baseline" is crucial—clinicians must assess current features that are due to catatonia rather than the underlying neurodevelopmental disorder by comparing against the patient's personalized baseline of premorbid neurobehavioral and motor symptoms. 3
Specific Motor Presentations
Motor abnormalities in pediatric catatonia may include:
- Rigidity (lead pipe type most common) 1
- Akinesia 1
- Intermittent tremors 1
- Involuntary movements 1
- Stupor 1
- Psychomotor agitation 1
- Posturing and mannerisms 1
Less common neurologic signs include positive Babinski, chorea, seizures, opisthotonos, trismus, and oculogyric crisis—none of which involve waxy flexibility. 1
Diagnostic Approach
Core Clinical Features to Assess
The hallmarks of catatonia are:
- Hyperthermia 1
- Altered mental status (ranging from alert mutism to agitation to stupor to coma) 1
- Muscle rigidity 1
- Autonomic instability 1
Manifestations of autonomic dysfunction may occur before other symptoms and include fever up to 41°C or higher, tachycardia, blood pressure instability, diaphoresis, pallor, cardiac dysrhythmia, sialorrhea, and dysphagia. 1
Diagnostic Criteria
Because there are no pathognomonic clinical or laboratory criteria, catatonia is a clinical diagnosis. 1 An international Delphi panel of NMS experts (which shares overlapping features with catatonia) assigned point values to various features, with rigidity receiving 17 points and mental status alteration receiving 13 points—but waxy flexibility was not specifically required. 1
Common Pitfalls and Caveats
Diagnostic Overshadowing
The biggest pitfall is attributing acute behavioral changes in children with NDD to their underlying condition rather than recognizing new-onset catatonia. 2, 3 Clinicians must actively look for deterioration from the child's individual baseline.
Historical Misconceptions
For several decades, catatonia was exclusively defined as a subtype of schizophrenia, leading to under-diagnosis in patients with other psychiatric and medical conditions. 4 This historical error continues to complicate recognition today. 4
Atypical Presentations
Catatonia is increasingly recognized in pediatric populations, with about 20% of cases related to underlying medical conditions including viral encephalitis, meningitis, seizure disorders, CNS lesions, endocrinopathies, and Wilson's disease. 5, 6 These medical causes must be ruled out while simultaneously managing symptoms.
Treatment Implications
Untreated catatonia can cause significant morbidity including severe medical complications, making timely recognition essential. 2 Treatment with benzodiazepines and/or electroconvulsive therapy (ECT) is effective, though children with NDD may respond differently to benzodiazepines and may require ECT for adequate response. 2