We present a case where malabsorption due to small intestinal bacterial overgrowth (SIBO) resulted in myelopathy, polyneuropathy, and bedbound state.

A 65-year-old male, presented to the hospital for six months of progressively worsening weakness, numbness and tingling in bilateral lower extremities causing bedbound status and development of decubitus ulcers. Past medical history was significant for prostate cancer status-post radiation, chronic ileus, SIBO, pancreatic insufficiency, and migraine. Recent workup at outpatient neuromuscular clinic was consistent with cervical myelopathy without cord compression and polyneuropathy likely secondary to Vitamin E and severe copper deficiency for which he had been started on supplementation, but no improvement was noted. The patient had seen gastroenterology for five years for management of chronic idiopathic ileus, SIBO, and pancreatic insufficiency. Previously, rifaximin had shown short term improvement in chronic diarrhea but had been stopped due to prohibitive cost. During this hospitalization, he was noted to have significant bilateral LE and mild bilateral UE weakness, absent reflexes in bilateral UE and 3+ reflexes in bilateral LE. Workup including NMO, MOG, and CSF studies was negative. MRI lumbar spine showed degenerative disc disease. The patient was started on rifaximin, neomycin, and TPN as SIBO breath test was concerning for methanogenic bacteria. There was a dramatic improvement in his diarrhea and neurological and functional status. He was able to ambulate 240 feet using rolling walker with physical therapy at discharge from rehab.

SIBO is an important cause of malabsorption and treatment with proper antibiotics is necessary along with supplementation. We saw rapid return of strength and function with antibiotic and TPN treatment. This case highlights the need to obtain a thorough history and treat non-neurological etiology of neurological conditions.