| 저자 |
Geun Su LEE1*, Na Na Lim1, Ki Hong Won1, Jin Sun Kang1, Sung Hoon Lee1, Eun Young Kang1, Hyun Kyung Lee1, Youn Kyung Cho1† |
[Introduction]Folate is one of the water-soluble B vitamins and is typically found in fresh green vegetables, legumes, citrus fruit, and liver. Folate deficiency is caused by lack of intake or absorption disorder and It is known to causes immunologic, hematologic, dermatologic, cardiovascular, and neurologic complications.
[Case]56-year-old woman was admitted to our hospital because of lower extremity weakness and neuropathic pain. In her past years, she had been drinking alcohol, losing appetite, and suffering from liver cirrhosis and mild cognitive impairment. The muscle bulk of the lower limbs was reduced and stretch reflexes were diminished. Babinski sign and ankle clonus were negative. Pain sensation was blunted over the feet and distal part of the legs. Brain MRI(fig. 1) and Lumbar MRI(fig. 2) were performed to find the cause of lower extremity weakness. Diffuse cortical atrophy was identified on brain MRI but there was no findings have been observed that may cause lower extrimity weakness. Neurophysiological study was conducted for suspected peripheral neuropathy. The principal electrophysiological abnormality(table 1) consisted of absent sensory action potentials in lower extremities, with mild slowing of the motor conduction velocities and markedly decreased amplitudes of both tibial nerves. So, she was diagnosed with axonal polyneuropathy. Work up was conducted on factors that might cause polyneuropathy including diabetes mellitus, thyroid dysfunction, renal failure, or nutritional dificiency. She had low serum folates concentrations on hematological assessment (Serum folate(>5.38ng/ml) 2.86, deficient, vitamin B 12 normal range). we prescribed folic acid 15mg per day and educated to correct dietary imbalances particularly the insufficient intake of fresh green vegetables to improve serum folate levels. Peripheral neuropathy caused by folic acid deficiency is known to respond to folic acid supplementation. But patients in this case was follow up has been lost as she moved to local nursing home.
[Discussion]The main characteristics of acquired folate-responsive polyneuropathies are (1) they are mixed sensorimotor types; (2) they either affect one or both of the lower extremities much more severely than the upper extremities. In our case, she manifested symmetric polyneuropathy with predominant involvement of the lower rather than the upper extremities. Nerve conduction studies indicated that axonal neuropathy was predominant in the lower extremities(table 1). We presumed that inadequated ingestion due to anorexia and mild cognitive impairmend could be considered as causative factors, and Liver cirrhosis is also thought to be a contributing factor, but mechanism underlying folate-responsive polyneuropathy remains unknown.
[Conclusion]Vitamin deficiency such and folate, which is rare compared to the past, should be considered the cause of peripheral neuropathy in patients with difficulty caring for themselves and poor intake. |
