SAT-375 A 59 Year Old Female with Isolated Vitamin B6 Deficiency and Muscle Spasms

Introduction Vitamins are essential micronutrients required by biological organisms in small quantities for maintaining basic cellular metabolism. Vitamin B6 is an important co-factor for many biochemical reactions in cellular metabolism related to the synthesis and catabolism of amino acids, fatty acids, neurotransmitters, and organelle-specific compounds, as well as in detoxifying reactive oxygen species within the cell. (1) Due to the role of Vitamin B6 in intracellular metabolism and synthesis of neurotransmitters, deficiency of the vitamin results in impaired transcellular signaling between neurons, and classically presents with muscular convulsions, hyperirritability, and peripheral neuropathy. (2) Case Presentation History We present a case of a 59-year old female with Type 2 diabetes who complained of muscle spasms. She experienced muscle spasms in her feet which have spread proximally to involve her legs. She also admitted to experiencing intermittent spasms in her left arm. The spasms occurred intermittently throughout the day and persist throughout the night, making it difficult for her to fall asleep. She had taken cyclobenzaprine twice daily and tried leg stretches, however her spasms persist. She had also tried baclofen in the past without significant alleviation of her symptoms. Evaluation An extensive investigation was conducted including tests for water-soluble vitamins. Her plasma pyridoxal 5-phosphate was 3 mcg/L (reference range 5-50 mcg/L), confirming vitamin B6 deficiency. She was also tested for Vitamins B1, B3, B12 and folate. None of the respective tests indicated deficiencies. Other test results were within normal limits. Treatment The patient received standard-dose intramuscular vitamin B6 injections for three weeks followed by oral supplements for 3 months. She was also given cyclobenzaprine (10 mg tablet) three times a day for muscle spasms in her legs. Although she had reported cyclobenzaprine did not significantly alleviate her spasms per se, it produces a sedative effect which improves her tolerance to the spasms and helps her to fall asleep at night. Conclusion This case illustrates the rare instance of isolated vitamin B6 deficiency with normal serum levels of other water-soluble vitamins, manifesting as myoclonic spasm involving the legs and arms in the absence of objective polyneuropathy. References (i1) Parra, Marcelina, Seth Stahl, and Hanjo Hellmann. “Vitamin B6 and its role in cell metabolism and physiology.” Cells 7.7 (2018): 84. (i2) Brown, Mary J., and Kevin Beier. “Vitamin B6 Deficiency (Pyridoxine).” StatPearls [Internet]. StatPearls Publishing, 2018.