Neuromyelitis optica spectrum disease coexisting with subacute combined degeneration: a case report.

BACKGROUND: Subacute combined degeneration (SCD) is a demyelinating disease characterized by vitamin B12 deficiency related segmental degeneration of the dorsal or lateral columns of the spinal cord. However, few cases have been reported as a comorbidity of SCD and neuromyelitis optica spectrum disease (NMOSD). CASE PRESENTATION: Herein, we describe a female patient (61-year-old) who had sensory deficits, paresthesia, and weakness of the distal extremities for over 2 months. She then received an initial diagnosis of SCD with typical inverted "V-sigh" hyperintensities over the posterior aspect of the spinal cord in magnetic resonance imaging (MRI - T2-weighted imaging), as well as megaloblastic anaemia in blood examinations. From the past history, there was no evidence of a dietary deficiency or gastric abnormalities. However, traditional treatment with vitamin B12 supplementation was ineffective. Hence, a demyelinating antibody examination showed that she had antibodies targeting aquaporin 4 (AQP4) in both the cerebrospinal fluid and serum, leading to the diagnosis of NMOSD. Her clinical symptoms were obviously improved after treatment with intravenous glucocorticoids. CONCLUSION: People who have nutritional deficiency or altered gastrointestinal function are more likely to develop SCD. This case raises the awareness that the poor therapeutic effects of simple vitamin B12 supplementation could be explained by immunoreactions against AQP4. A better recognition will be of great importance for the correct diagnosis of the comorbidity, as well as for essential treatment and even a better prognosis.

Myeloradiculoneuropathy due to vitamin B12 deficiency: an unusual clinical and radiological presentation.

A 42-year-old man from rural India presented with asymmetric progressive paraparesis mimicking compressive dorsal myelopathy, followed by distal upper limb, truncal and neck-flexor weakness, further complicated by acute urinary retention. His sensory deficits were marked by loss of joint position sense (JPS) and graded loss of vibration sense, along with a definite sensory level. Deep tendon jerks were hypo-to-areflexic, plantar was bilaterally extensor. He had become less attentive and occasionally failed to keep track with conversations. A syndromic diagnosis of myeloradiculoneuropathy with cognitive impairments was made. Further tailored investigations revealed vitamin B12 deficiency with positive anti-parietal cell antibody. Diagnosis of subacute combined cord degeneration (SACD) was confirmed. Neuro-imaging revealed intramedullary intensity changes only along lateral aspect of spinal cord instead of characteristic posterior involvement. Following parenteral vitamin B12 supplementation, patient started showing improvement in motor power and subjective sensory symptoms. His bladder symptoms persisted initially, however recovered finally after 6 months.

Subacute combined degeneration of the spinal cord is associated with tripterygium glycoside tablet usage.

BACKGROUND: Subacute combined degeneration (SCD) is a neurodegenerative disease caused by vitamin B12 deficiency. The lesions mainly involve the posterior cord, lateral cord, and peripheral nerves. Occasionally, the lesions also involve brain white matter and optic nerves in severe cases. Reports of drug-induced impaired absorption and metabolism of vitamin B12 resulting in SCD are scarce. INTRODUCTION: A patient developed SCD after long-term use of tripterygium glycoside tablets in the treatment of glomerulonephritis. However, after discontinuation and vitamin B12 treatment with tripterygium glycoside tablet, the symptoms of SCD were significantly resolved. CONCLUSION: Drug-induced SCD is a less commonly reported cause of the disease. Tripterygium glycoside tablets can induce adverse reactions in the digestive system, causing damage to absorption and metabolism of vitamin B12. Physicians should be aware of the possibility of tripterygium glycoside tablet-induced SCD after excluding more common causes such as inadequate dietary intake and impaired absorption due to gastrointestinal diseases or genetic disorders.

Recreational nitrous oxide abuse related subacute combined degeneration of the spinal cord in adolescents - A case series and literature review.

BACKGROUND: Nitrous oxide (N2O) is a commonly used inhaled anesthetic in outpatient dental procedures. However, the increasing recreational use of N2O may result in vitamin B12 deficiency-related neurologic and psychiatric symptoms. The aim of this study was to demonstrate the clinical features of chronic N2O abuse in pediatric patients. METHODS: Patients under 20 years of age who were diagnosed with N2O-induced subacute combined degeneration of the spinal cord from 2012 to 2018 were enrolled in this study. Clinical presentations, laboratory, imaging, ancillary studies, treatments and outcomes were analyzed. RESULTS: Nine patients were included, all of whom presented with symptoms of myeloneuropathy including limb numbness, limb weakness or unsteady gait. Six patients had low or low-normal vitamin B12 (cyanocobalamin) levels. Eight patients had evidence of subacute combined degeneration of the spinal cord via neuroimaging studies. All of the patients received vitamin B12 supplementation as treatment. All had full recovery of muscle power within 2 months. Five patients had persistent sensory deficits. CONCLUSION: Chronic N2O abuse can cause permanent neurological damage if not treated promptly. Clinical staff should be aware of the various presentations of neurotoxicity related to N2O abuse.

Nitrous Oxide-induced Subacute Combined Degeneration Presenting with Dystonia and Pseudoathetosis: A Case Report.

PURPOSE: Nitrous oxide (N2O) is neurotoxic by interfering with vitamin B12 bioavailability. The clinical picture is indistinguishable to that of subacute combined degeneration (SCD). A movement disorder might occur though it is not a characteristic feature. We report a patient with N2O-induced SCD, exhibiting a combination of different involuntary movements. CASE REPORT: A 20-year-old woman presented with one month of progressive unsteady gait, involuntary movements and tingling sensation in a stocking-glove distribution. She had used N2O and ketamine intermittently for recreational purposes for about two years. Neurological examination demonstrated normal cranial nerve functions except for dystonia in the facial muscle and tongue. Her muscle strength was full, but there were bilateral hyperreflexia and extensor plantar response. She exhibited dystonia in four limbs with athetoid movement in fingers and toes, worsened by eye closure. Vibration and proprioception were impaired. Laboratory tests revealed anemia (Hb: 9.9 g/dl) with normal mean corpuscular volume (85.7 fL) and decreased iron level (22 µg/dl) while other results were normal including serum vitamin B12 level (626 pg/ml). Magnetic resonance imaging showed a hyperintense lesion from C1 to C6 level in the posterior column. She was diagnosed as having SCD caused by N2O abuse, presenting with generalized dystonia and pseudoathetosis. The involuntary movements disappeared with vitamin B12 supplementation. CONCLUSION: Movement disorders may be the rare manifestations of SCD associated with N2O abuse. Early recognition of the etiology is vital because it is treatable with vitamin B12 and methionine.

Pitfalls in the diagnostic evaluation of subacute combined degeneration.

We report a case of a 43-year-old man presenting with a 2-week history of painless ascending sensory disturbances, suspected to be suffering from acute inflammatory polyneuropathy. On clinical examination, deep tendon reflexes were preserved and muscle strength was 5/5 everywhere. Gait was ataxic with positive Romberg test. Lumbar puncture was normal and electroneurography demonstrated demyelination. With spinal cord involvement centred on the posterior tracts on MRI, differential diagnosis focused on cobalamin deficiency. Initial laboratory work up showed nearly normal holotranscobalamin (43 pmol/L, normal>50) suggesting no vitamin B12 deficiency. Surprisingly, further testing including methylmalonic acid (3732 nmol/L, normal<271) and homocysteine (48.5 µmol/L, normal<10) showed an impairment of vitamin B12-dependent metabolism leading to the diagnosis of subacute combined degeneration. Only after repeated history taking did the patient remember having taken tablets containing cobalamin for 3 days before hospitalisation. In case of B12 deficiency, holotranscobalamin can rapidly normalise during supplementation, whereas methylmalonic acid and homocysteine might help to detect B12 deficiency in patients who recently started supplementation.

Contribution of spinal MRI for unsuspected cobalamin deficiency in isolated sub-acute combined degeneration.

Sub-acute combined degeneration (SCD) is a rare cause of demyelination of the dorsal and lateral columns of the spinal cord and is a neurological complication due to vitamin B12 deficiency. Revealing forms of SCD without anemia are rare. We report a case of SCD of the spinal cord in a 33-year-old woman without anemia but with a 10-month history of paresthesis and urine imperiosity. Magnetic resonance imaging (MRI) of the spine showed intramedullary hyperintensity seen on T2-weighted images in the posterior column of the cervico-dorsal spinal cord, extending from C1 to D1. A diagnosis of SCD of the spinal cord was considered and confirmed by a low serum cobalamin. The patient was treated with vitamin B12 supplements and showed gradual improvement in her clinical symptoms.