Catatonia versus neuroleptic malignant syndrome: the diagnostic dilemma and treatment

Drug-related catatonia in youths: real-world insights from the WHO Safety Database

Catatonia is characterized by psychomotor alterations and reduced contact with the environment. Initially linked to schizophrenia, it also occurs in mood disorders or organic conditions. In children, catatonia remains poorly delineated, despite dramatically increasing the risk of premature death. As data on pediatric drug-induced catatonia bears many uncertainties, we aimed to characterize its age-dependent patterns, using real-world data from the WHO safety database (VigiBase®).VigiBase® was queried for all reports of catatonia registered up to December 8th 2022. Reports involving patients <18 years were classified into 3 groups: ≤23 months, 2-11 years, and 12-17 years. Disproportionality analyses relied on the Reporting Odds Ratio (ROR), and the positivity of the lower end of the 95% confidence interval of the Information Component (IC) was required to suspect a signal. Catatonia was evoked in 421 pediatric reports. In infants, vaccines were leading. In children, the main signals involved haloperidol (ROR 104.3; 95% CI 45.6-238.5), ondansetron (ROR 40.5; 95% CI 16.5-99.5), and ciclosporin (ROR 27.4; 95% CI 13.8-54.1). In adolescents, chlorpromazine (ROR 199.1; 95% CI 134.8-294.1), benzatropine (ROR 193; 95% CI 104.1-361.6), and olanzapine (ROR 135.7; 95% CI 104.6-175.9) reached the highest RORs. In infants, catatonia was related to vaccines, it was ascribed to multiple drugs in children, and mainly to psychotropic drugs in adolescents. Less suspected drugs, such as ondansetron, were highlighted. Despite limitations inherent in spontaneous reporting systems, this study supports that a careful anamnesis is warranted to separate catatonia associated with medical conditions from drug-induced catatonia in pediatric patients.

Catatonia as a putative nosological entity: A historical sketch

Kahlbaum was the first to propose catatonia as a separate disease following the example of general paresis of the insane, which served as a model for establishing a nosological entity. However, Kahlbaum was uncertain about the nosological position of catatonia and considered it a syndrome, or “a temporary stage or a part of a complex picture of various disease forms”. Until recently, the issue of catatonia as a separate diagnostic category was not entertained, mainly due to a misinterpretation of Kraepelin’s influential views on catatonia as a subtype of schizophrenia. Kraepelin concluded that patients presenting with persistent catatonic symptoms, which he called “genuine catatonic morbid symptoms”, particularly including negativism, bizarre mannerisms, and stereotypes, had a poor prognosis similar to those of paranoid and hebephrenic presentations. Accordingly, catatonia was classified as a subtype of dementia praecox/schizophrenia. Despite Kraepelin’s influence on psychiatric nosology throughout the 20^th century, there have only been isolated attempts to describe and classify catatonia outside of the Kraepelinian system. For example, the Wernicke-Kleist-Leonhard school attempted to comprehensively elucidate the complexities of psychomotor disturbances associated with major psychoses. However, the Leonhardian categories have never been subjected to the scrutiny of modern investigations. The first three editions of the DSM included the narrow and simplified version of Kraepelin’s catatonia concept. Recent developments in catatonia research are reflected in DSM-5, which includes three diagnostic categories: Catatonic Disorder due to Another Medical Condition, Catatonia Associated with another Mental Disorder (Catatonia Specifier), and Unspecified Catatonia. Additionally, the traditional category of catatonic schizophrenia has been deleted. The Unspecified Catatonia category could encourage research exploring catatonia as an independent diagnostic entity.

Neuroleptic malignant syndrome: an easily overlooked neurologic emergency

Neuroleptic malignant syndrome is an unpredictable iatrogenic neurologic emergency condition, mainly arising as an idiosyncratic reaction to antipsychotic agent use. It is characterized by distinctive clinical features including a change in mental status, generalized rigidity, hyperpyrexia, and dysautonomia. It can be lethal if not diagnosed and treated properly. Mortality and morbidity attributed to this syndrome have recently declined markedly due to greater awareness, earlier diagnosis, and intensive care intervention. In most cases, the syndrome occurs as a result of a rapid increase in a dose of neuroleptic, especially one of the long-acting ones. Pathophysiology behind this syndrome is attributed to a dopamine receptor blockade inside the neurons rendered by the offending drug and excessive calcium release from the sarcoplasmic reticulum of skeletal myocytes. Laboratory tests, although not diagnostic, may assist in assessing the severity of the syndrome and also the consequent complications. The syndrome has been described in all age groups and occurs more in males than in females. Genetics appears to be central regarding the etiology of the syndrome. Stopping the use of the offending agent, cold intravenous fluids, and removal of the causative agent and its possible active metabolites is the cornerstone of treatment. Periodic observation of psychotic patients recently started on antipsychotic medications, especially those being treated with depot preparations, may aid to an early diagnosis of the syndrome and lead to early treatment.