Psychiatric syndromes in pernicious anaemia--a case report.

Surveys of psychiatric population had previously shown a high incidence of patients with low serum vitamin B12. A variety of psychiatric syndromes have been described, ranging from mild disturbance in mood state like depression to maniacal excitement; psychotic conditions like paranoid states and schizophrenia; and cognitive dysfunctions such as memory defect, delirium and dementia. A case of a 67-year-old Chinese lady suffering from pernicious anaemia, but presenting with prominent paranoid delusions is reported. Treatment with cyanocobalamine and anti-psychotic medication led to prompt resolution of her psychotic experience. Subsequently she developed a transient depressive syndrome which also responded well to a short course of antidepressant.