A 73 year-old woman presented with lethargy and decreased responsiveness for one day. She did not respond to her name or noxious stimuli and did not follow commands. She would spontaneously repeat the phrase “I see the light” but was otherwise non-verbal. Waxy rigidity was noted on passive extension and flexion of her extremities. Pupillary response was normal with intact corneal reflexes. No incontinence was noted.
Her hematologic profile, chemistries, liver function tests, and thyroid studies revealed no significant abnormalities. Electrocardiogram revealed no acute changes. A urine toxicology screen was negative for all tested substances. Urinalysis and chest x-ray revealed no evidence of infection. No abnormalities were revealed on non-contrast head CT. No epileptiform activity was seen on electroencephalogram.
Due to suspicion for catatonia, the patient received 1 mg of lorazepam with temporary improvement in her symptoms. She responded by opening her eyes, moving around in the bed, lifting her head, and experiencing temporary relief of rigidity in her extremities. A bedside lumbar puncture was attempted by anesthesiology. Due to agitation, a second dose of lorazepam was administered prior to the procedure, but because of continued movement the procedure was aborted. However, within the hour she was more interactive, following commands, making jokes, and having meaningful conversations. She maintained this improved mental status, allowing psychiatric evaluation and adjustments to her medications for depression. She was discharged with full resolution of her presenting symptoms.
Discussion:
Acute encephalopathy is a condition commonly encountered by hospitalists. Catatonia is a behavioral cause of acute encephalopathy characterized by motor disruption in a background of psychiatric or general medical disorders that may be overlooked if not considered on initial presentation. The approximate incidence of catatonia is 10% among psychiatric inpatients. There are three subtypes: retarded, malignant, and excited. In retarded catatonia, inhibited movement, rigidity, posturing, mutism, and negativism are the prominent signs as demonstrated by this case.
First line treatment, regardless of the subtype, is a benzodiazepine or electroconvulsive therapy (ECT). Retarded catatonia is most often initially treated with lorazepam. A lorazepam challenge test is positive when there is partial, temporary relief of signs 5-10 minutes after the first or second dose of intravenous lorazepam (1-2 mg). However, a negative response does not rule out catatonia. Retarded catatonia patients that do not respond to benzodiazepines are treated with ECT. Catatonia generally has a good prognosis, especially the retarded and excited subtypes.
Conclusions:
Encephalopathy is a condition that is frequently admitted to hospital medicine floors, and catatonia should be considered as a cause when its characteristic signs are present.