Increased biogenic catecholamine and metabolite levels in two patients with malignant catatonia

The pathophysiology of malignant catatonia, a rare life-threatening psychiatric syndrome, has not yet been elucidated. This paper reports on two patients with malignant catatonia who showed elevated urinary or plasma catecholamine levels. Patient 1 had high catecholamine and metabolite levels in a 24-hour urine sample, and patient 2 had elevated plasma catecholamine levels. These findings indicate the presence of peripheral sympathetic nervous system hyperactivity in malignant catatonia. Symptoms of autonomic dysfunction, including tachycardia, labile blood pressure, and diaphoresis, are typical features of malignant catatonia and may be related to the increased levels of biogenic amines in these cases. Although the findings in the present study cannot entirely explain the pathophysiology of malignant catatonia, they do indicate that hyperactivity of the sympathetic nervous system may be involved in the pathology of this condition.