Hypernatraemia associated delirious catatonia responsive to electroconvulsive therapy

Background

Delirium is an acute brain dysfunction characterized by disturbances in attention, awareness, and cognition, and is common in medically ill patients. Catatonia is a severe neuropsychiatric syndrome with motor and behavioral abnormalities that may occur in both psychiatric and medical conditions [1].Although DSM-5 does not allow their co-diagnosis, increasing evidence suggests that delirium and catatonia may coexist, particularly in medically ill and older patients, with important implications for diagnosis and treatment [2].

Case Description:A 58-year-old woman presented with acute onset of suspiciousness, aggression, confusion, and behaviour posing risk to others, accompanied by paranoid delusions, auditory hallucinations, reduced sleep, and appetite over 2–3 days. On the day of admission, she failed to recognize her children and exhibited disorganized and aggressive behaviour. On examination, she was stuporous with fluctuating levels of consciousness, impaired orientation, and marked psychomotor retardation. Prominent catatonic features, including mutism, immobility, and stereotypies, were observed. The Bush–Francis Catatonia Rating Scale score was 13. Laboratory testing revealed hypernatraemia (154 mmol/L), while neuroimaging and electroencephalography were unremarkable. Despite correction of sodium levels, both catatonic and psychotic symptoms persisted. Electroconvulsive therapy was initiated, resulting in improvement in consciousness after two sessions. Antipsychotic treatment with olanzapine and quetiapine was subsequently introduced. Following eight sessions of electroconvulsive therapy, psychotic symptoms fully resolved. The patient remained clinically stable at follow-up, with no active psychiatric symptoms.

Methods

A comprehensive clinical and etiological evaluation was conducted, including psychiatric examination, laboratory testing, neuroimaging (MRI, CT), electroencephalography, and cerebrospinal fluid analysis. Catatonic symptoms were assessed using the Bush–Francis Catatonia Rating Scale. Supportive treatment included hypotonic fluid replacement and intravenous thiamine. Electroconvulsive therapy was initiated due to persistent catatonic and psychotic symptoms. Empirical corticosteroid treatment was briefly administered for suspected autoimmune encephalitis and discontinued after negative antibody results.

Results

The patient exhibited prominent catatonic features, including stupor, mutism, stereotypies, and psychomotor retardation, alongside fluctuating levels of consciousness, supporting a diagnosis of delirious catatonia. Laboratory findings revealed hypernatraemia (154 mmol/L), suggesting a metabolic contribution to the clinical presentation. Neuroimaging and electroencephalography were unremarkable. Despite normalization of sodium levels, catatonic and psychotic symptoms persisted. Electroconvulsive therapy was initiated, resulting in rapid improvement in consciousness after two sessions. Antipsychotic treatment with olanzapine and quetiapine was subsequently introduced. Following eight sessions of electroconvulsive therapy, psychotic symptoms fully resolved. The patient remained clinically stable at follow-up with no active psychiatric symptoms.

Conclusions

This case suggests that hypernatraemia may represent a reversible metabolic trigger for delirious catatonia. Early recognition of catatonic features within delirium is crucial, as it directly influences diagnostic formulation and treatment decisions. In such cases, standard approaches may be insufficient, and electroconvulsive therapy may represent an effective and time-sensitive intervention, particularly when benzodiazepines are limited by coexisting delirium. These findings highlight the need for heightened clinical awareness and support reconsideration of the DSM-5 exclusion of catatonia in the presence of delirium.

References

1-Amouri, J., Andrews, P. S., Heckers, S., Ely, E. W., & Wilson, J. E. (2020). A case of concurrent delirium and catatonia in a woman with coronavirus disease 2019. Psychosomatics, 61(5), 556–560. https://doi.org/10.1016/j.psym.2020.09.002 2-Oldham, M. A., & Lee, H. B. (2015). Catatonia vis-à-vis delirium: The significance of recognizing catatonia in altered mental status. General Hospital Psychiatry, 37(5), 554–559. https://doi.org/10.1016/j.genhosppsych.2015.06.011