Subacute Combined Degeneration of the Spinal Cord Induced by Nitrous Oxide Abuse: A Rare Patient Presentation to a Spine Surgery Clinic: Illustrative Case.

Subacute combined degeneration (SCD) of the spinal cord is a disease involving the lateral and posterior columns of the spinal cord that can manifest in patients with vitamin B12 deficiency. Nitrous oxide (N2O)-induced SCD of the spinal cord is a result of N2O interfering with the metabolism of vitamin B12 and results in nervous system demyelination. This is an infrequent complication of N2O anesthesia; however, cases are rising with recreational N2O use. This case report describes a patient with SCD of the spinal cord induced by recreational N2O abuse. The patient presented to a spine surgery clinic with a 3-week history of progressive global weakness and paresthesias. After a detailed history and physical examination, the diagnosis was made and supported by various tests and imaging findings. Despite marked neurologic deficits, the patient's symptoms improved markedly with therapy and vitamin B12 supplementation. Spine surgery clinicians may be confronted with these cases and should be aware of this atypical presentation of SCD. As in our case, patients may present with neurologic deficits of unclear etiology. Neurologic dysfunction may be irreversible; therefore, accurate diagnosis, medical treatment, and complete neurologic evaluation are of the utmost importance to prevent additional progression.

Not a Laughing Matter: When Nitrous Oxide Causes Functional Vitamin B12 Deficiency.

Subacute combined degeneration (SCD) is an acquired neurologic complication from prolonged vitamin B12 deficiency. As a result of dorsal and lateral spinal cord column degeneration, patients present with a range of neurological symptoms, including paresthesias, ataxia, and muscle weakness. Without prompt treatment, irreversible nerve damage occurs. Here we present a young man who developed progressive ascending paresthesias and lower extremity weakness after escalated nitrous oxide use. This case highlights the importance of considering SCD from nitrous oxide toxicity when patients present with progressive ataxia, paresthesia, and lower extremity weakness.

Nitrous oxide abuse induced subacute combined degeneration despite patient initiated B12 supplementation.

INTRODUCTION: Nitrous oxide (N2O) is a commonly used inhaled anesthetic that is legal to purchase as a food additive and is popular as a recreational euphoric drug. Abuse causes a functional B12 deficiency, leading to clinical features and imaging consistent with subacute combined spinal cord degeneration (SCD). CASES: Poison Center medical records from four patients are reviewed in this series. Four patients presented with lower extremity weakness, paresthesias and gait abnormalities in the setting of chronic N2O abuse. Each reported using 50-150 N2O cartridges ("whippets") almost daily for months to years, and reported supplementing with oral B12 at the recommendation of other users and online forums. None reported prior B12 deficiency or dietary restrictions, and none exhibited hematologic abnormalities. RESULTS: All patients had clinical signs of neurotoxicity including weakness and ataxia. Additionally, all had elevated methylmalonic acid and homocysteine concentrations with normal B12 indicating a functional B12 deficiency. Three had imaging consistent with SCD despite home supplementation The MRI in the fourth case was inconclusive due to movement artifact. CONCLUSION: We report four cases of subacute combined degeneration induced by recreational nitrous oxide abuse despite self-administered vitamin B12 supplementation.

Degeneración combinada subaguda de la médula espinal por deficiencia de vitamina B12 / Subacute combined degeneration of the spinal cord due to vitamin B12 deficiency

Introducción: la degeneración combinada subaguda de la médula espinal es una mielopatía inducida por deficiencia de vitamina B12. Produce disestesias simétricas, alteraciones de la sensibilidad superficial y vibratoria. En estadios avanzados causa defectos de la memoria, el aprendizaje, comportamiento, gusto y olfato.Objetivo: presentar el caso de una paciente diagnosticada y tratada por degeneración combinada subaguda de la médula espinal, afección rara en Cuba.Presentación del caso: paciente femenina, de 50 años de edad. Refirió que dos años antes del ingreso presentó debilidad progresiva en los miembros inferiores, añadiéndose frialdad y adormecimiento de las cuatro extremidades, marcha tambaleante, palpitaciones, fatiga, cefalea, disnea de esfuerzo y tinte de la piel de color amarillo limón. Se le realizaron exámenes complementarios de laboratorio, imagenológicos e histológicos. La lámina periférica mostró anisocitosis y macrocitosis marcadas, presencia de poiquilocitos y policromatofilia. A la paciente se le administró diariamente, en dosis única, 100 mg de vitamina B12 durante 10 días, con recuento leucocitario diario. Fue egresada a los 15 días, con indicaciones para seguir el tratamiento. Transcurridos tres meses recuperó 70 por ciento de sus capacidades cognitivas y motoras, con movilidad de las cuatro extremidades.Conclusiones: el diagnóstico de esta enfermedad precisa de una correcta aplicación del método clínico, y la realización de exámenes de laboratorio, imagenológicos e histológicos. Ello fue posible por la atención multidisciplinaria entre los especialistas de medicina interna, hematología, imagenología y gastroenterología. En este caso la edad de la paciente no estaba comprendida en el rango de presentación de la enfermedad(AU)

Introduction: subacute combined degeneration of the spinal cord is a myelopathy induced by vitamin B12 deficiency. It produces symmetric dysesthesias, alterations of superficial and vibratory sensitivity. In advanced stages it causes defects of memory, learning, behavior, taste and smell.Objective: to present the case of a patient diagnosed and treated by subacute combined degeneration of the spinal cord, a rare condition in Cuba.Case presentation: female patient, 50 years old. She reported that two years before admission she presented progressive weakness in the lower limbs, adding coldness and numbness of the four limbs, wobbly march, palpitations, fatigue, headache, dyspnea and lemon yellow skin tint. She was given complementary laboratory, imaging and histological exams. The peripheral lamina showed marked anisocytosis and macrocytosis, presence of poikilocytes and polychromatofilia. The patient was given daily, in a single dose, 100 mg of vitamin B12 for 10 days, with daily white blood cell count. She was discharged 15 days after, with instructions to continue the treatment. After three months she recovered 70 percent of her cognitive and motor skills, with mobility of the four limbs.Conclusions: the diagnosis of this disease requires a correct application of the clinical method, and the realization of laboratory, imaging and histological exams. This was possible due to the multidisciplinary care among specialists in internal medicine, hematology, imaging and gastroenterology. In this case, the age of the patient was not included in the range of presentation of the disease(AU)

Subacute combined degeneration caused by nitrous oxide intoxication: case reports.

PURPOSE: Case reports with a comprehensive review of the current literature concerning subacute combined degeneration induced by nitrous oxide inhalation. A differential diagnosis should be considered when young patients present with progressive myelopathy because that the misuse of nitrous oxide has potentially serious outcomes. CASES REPORT: Three young patients aged from 18 to 24, one male and two females, were diagnosed with progressive ascending numbness in four limbs or both legs and ataxia. They all had been inhaling nitrous oxide from whipped-cream containers for several months. A cervicothoracic magnetic resonance imaging scan revealed long segmental hyperintensity changes at the posterior column of the spinal cord. Serological examination showed a low level of vitamin B12. Subacute combined degeneration of the spinal cord was diagnosed and the etiology was considered related to nitrous oxide misuse. Their neurological status, neuroimage, and neurophysiologic condition improved after vitamin B12 supplementation and cessation of nitrous oxide inhalation. CONCLUSION: Iatrogenic usage of nitrous oxide apparently resulted in subacute combined degeneration in our three patients. Recently, nitrous oxide misuse has increased among young people. Subacute combined degeneration of the spinal cord should be considered as a possible outcome of such abuse.

Reversible myelopathy with vitamin B12 deficiency.

Vitamin B12 deficiency causes haematological, gastrointestinal, psychiatric and neurological diseases. Subacute combined degeneration (SCD) of the spinal cord, characterised by degeneration of the lateral and posterior columns, is often found due to vitamin B12 deficiency. We report SCD occurring in a 57-year-old man who presented with a 2.5-month history of gradually progressing tingling in the fingers and toes and neck ache. Laboratory data revealed vitamin B12 deficiency and magnetic resonance (MR) imaging of the cervical spinal cord demonstrated abnormal hyperintense signal changes on T2-weighted imaging of the posterior columns. In our case, follow-up MR imaging findings correlated well with clinical outcome after treatment with vitamin B12 supplements. Neurological symptoms in vitamin B12 deficiency are frequent. Early spinal MR imaging assists in the early diagnosis and treatment of the disease.