An intriguing case of idiopathic flaccid quadriparesis and cerebellar ataxia in an HIV patient on Anti-Retroviral Therapy(ART)

Abstract

Background: Vitamin B12 deficiency is not a frequently considered diagnosis among HIV patients with neuropsychiatric disorders in Africa despite some medical literature stating that lack of this vitamin is not uncommon among this population. We highlight a case that further demonstrates this fact. Case Description: A 62 y old who was receiving ART from a major centre,presented to us with a 2 w history of progressive weakness of the lower limbs that was followed by that of the upper limbs,inability to walk,dizziness as well as prickly pains in the hands and feet. He had been on ART for 11 y and was currently on the 3rd line regimen Darunavir/Ritonavir/Raltegravir/Abacavir. His CD4 count was 544/ml. Latest viral load was not known. Examination revealed a sick-looking,middle aged male with no pallor,pyrexia,lymphadenopathy or edema. Had slowed mentation,dysarthria but no craniopathies or meningeal signs. Had normal muscle bulk but decreased tone and reflexes in upper and lower limbs,with power grade 3 in upper limbs and grade 2 in lower limbs. Tests for coordination identified dysmetria and dysdiadochokinesia in the upper limbs implying cerebellar ataxia. Coordination in the lower limbs could not be tested due to the sginificant weakness (only grade 2 power). There was a sensory level at L3 and loss of joint position sense. The Chest X-ray and brain CT scan were normal. Laboratory tests for common coinfections: tuberculosis(urine LAM),toxoplasmosis,cryptococcus,Hepatitis B,Hepatitis C,Syphilis(TPHA),brucellosis(BAT) were all negative. The vitamin B12 level was 169 pg/ml(normal range 191–943). Treatment was with daily cyanocobalamine 1000 micrograms for 1 w followed by weekly doses for 1 m and now monthly maintenance dose. Improvement occurred rapidly in the first one week and the patient was able to walk with aid of a walking stick by end of the second week(videos to be shown). Discussion: Our case presented with both features of cerebellar ataxia and subacute combined degeneration of the spinal cord Conclusion: This case has shown the importance of vitamin B12 among the causes of neuropsychiatric illness among HIV patients. It also advocates for need for further research in this area.