ABSTRACT
In this case study we describe a man who came to a mental health care centre (MHCC) with difficult to interpret complaints such as loss of fear and empathy, apathy and cognitive symptoms. In addition, he experienced a pronounced fatigue. Later he suffered from cold extremities, bilateral hypoesthesia of the hands and paresthesias of the legs. Routine laboratory tests initially showed no abnormalities. Only later a decreased hemoglobin and vitamin B12 value was seen in the context of a pernicious anemia. A treatment with vitamin B12 supplementation was started, after which gradual improvement of the symptoms was seen. This case study shows that vitamin B12 deficiency can result in both psychiatric and cognitive symptoms including memory and attention problems. The initial presentation of pernicious anemia can involve only psychiatric symptoms before neurological and hematological symptoms are present and before anemia is objectively diagnosed.