SERUM B12 DEFICIENCY;

NEUROPSYCHIATRIC MANIFESTATIONS

Abstract

Objective: To determine the frequency of various neurological and psychiatric symptoms associated with B12 deficiency.
Study design: Observational and descriptive study. Place and duration of study: The study was conducted on patients presenting to the
neurology clinics and inpatients who were admitted through the emergency department at Aga khan University Hospital Karachi, from 1st
July 2011 to March 2012. Subjects and methods: 150 patients of either gender and age more than 18 years. Detailed history was taken
from all the patients with special regard to anemia. Inclusion criteria were that patients above 18 years of age of either sex with low serum
B12 levels. Patients having any type of neurological tumors, major ischemic stroke, major intracranial haemorrhage, patients on
neuroleptic medications and any evidence of toxin induced neuropathy were excluded. All patients underwent for specific investigation
complete blood count, serum B12 levels (derived by Radio Assay method (RIA). Further investigations Nerve Conduction Studies /
Electromyography and CT Scan / Magnetic resonance Imaging of the Brain / spinal cord were carried out as and when required,
depending on the clinical scenario. Results: There were 69 (46%) males and 81(54%) females. Female to male ratio was 1:0.8. The age
ranged between 18 to 90 years with the mean age of 45.7+ 5.6. Out of 150 patients 107 patients (71.3 %) had severe vitamin B 12
deficiency while 43 (28.7%) had mild to moderate deficiency. Neurological manifestations which were observed included; Memory was
impaired in 13 (8.7%) of the patients. Dysarthia, along with other cerebellar signs (Nystagmus and dysdiadochokinesia) was present in
9 patients (6%). 4 patients (2.7%) sought medical attention regarding their abnormal gait and their neurological examination revealed
extensor planter responses and hyperreflexia. Cranial nerve examination revealed Anosmia in 2 (1.3%) and upper motor neuron facial
weakness in 1 (0.66%) patients. Motor weakness was found in 2 patients (1. 3%), and spasticity in 2 (1.3%) patients. 5 patients (3.3%)
had sensory complains and were found to have impaired pain and touch perception. Proximal muscle weakness in one patient while
another patient had asymmetric muscle weakness and rest of the patients had normal muscle power. None of the patient had autonomic
dysfunction. In six neuropsychiatric problems were commonly seen in vitamin B 12 deficient people. In these patients depression was
observed in 16%, agitation 12.7 %, memory impairment 8.7%, cerebellar signs and dysarthria 6%, sensory symptoms 3.3% and gait
abnormality and hyperreflexia and extensor planters 2.7 %. Conclusions: Various Neuropsychiatric problems are associated with vitamin
B 12 deficiency and the most common Neuropsychiatric illness found in these patients were depression, agitation, and memory
impairment.