“Whippets”-Induced Cobalamin Deficiency Manifesting as Cervical Myelopathy

Abstract

This patient presented with the symptoms and signs of Cbl deficiency. The MRI lesions in the posterior columns aided the diagnosis. Physicians need to have a high level of suspicion in cases of unexplained Cbl deficiency and myelopathy.

Subacute combined degeneration of the spinal cord in a patient abusing nitrous oxide and self-medicating with cyanocobalamin

“…6 When abused chronically and in high volume, nitrous oxide has been associated with myelopathy related to vitamin B 12 deficiency, a disorder in which patients commonly have paresthesia, ataxia, and loss of position and vibration senses. [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] Other cases have also demonstrated the manifestation of myelopathy from acute nitrous oxide exposure via anesthesia in patients with underlying vitamin B 12 deficiency. [21][22][23][24][25][26] The spinal cord abnormality caused by vitamin B 12 deficiency, often seen on magnetic resonance imaging (MRI) as an irregular demyelination of white matter, is known diagnostically as subacute combined degeneration (SCD).…”

“…20 The literature demonstrates that with cyanocobalamin supplementation and abstinence from nitrous oxide use, significant-to-total recovery from SCD can occur within 14 days to 21 months. [6][7][8][9][10][12][13][14][15]17,[19][20][21][22][23][24][25] However, this evidence is limited to noncontrolled studies and case reports involving follow-up encounters. One observational study reviewed outcomes in 57 cases of SCD and showed that although 86% of patients treated with cyanocobalamin had some recovery from neurologic symptoms, only 14% had total recovery at a range of 1-84 weeks after diagnosis.…”

“…daily for a minimum of five days, with continued intermittent dosing until symptoms abate. 6,[8][9][10][11][13][14][15]17,19,22,23,25 Cyanocobalamin supplementation in primary vitamin B 12 deficiency via the parenteral route is well documented, with doses ranging from 100 to 1000 mg i.m. administered daily or every 48 hours for one to two weeks followed by maintenance with 100-1000 mg i.m.…”

Nitrous oxide myelopathy posing as spinal cord injury

“…This finding in previous literature could explain the rapid recovery that would not typically be observed in central cord myelopathy. 6,8,15,16,18 Nitric oxide, a rapid and interchangeable form of nitrous oxide in the body, is implicated in the pathophysiology of secondary injury in spinal cord trauma. Liu and associates demonstrated a rapid increase of nitric oxide within 60 minutes of injury 17 .…”

“…It is frequently abused for its euphoric and anesthetic effect. 8,24 The effects of nitrous oxide on the spinal cord have been reported in the literature, 4,6,7,15,16,18,19,25,31 however, the unique and insidious presentation after cervical trauma has not been documented. Since the abuse of nitrous oxide is increasing in prevalence, this may be an important mechanism for spinal cord injuries and should be considered in the differential in the acute care setting.…”