Nonspecific low back pain as initial presentation of Morvan's syndrome successfully treated with therapeutic plasma exchange

Abstract

Morvan's syndrome is a rare, complex neurologic disorder characterized by neuromyotonia, dysautonomia and neuropsychiatric features. We present a 22-year old, previously healthy man with 2 month duration of nonspecific and nonradiating low back pain which was evaluated in two neurologic clinics and resulted with no specific diagnosis. Later, in 2-week time, our patient developed many other „classical“ symptoms of Morvan's syndrome: insomnia, hallucinations, agitation, hyperhidrosis, drooling, weight loss, itching, neuropathic pain and prominent twitching of muscles mostly in the lower limbs. Extensive diagnostic evaluation was done. Normal findings were observed for: routine hematology and biochemistry except for CK which was slightly elevated (380, normal values 50-177); tumor markers, hormones (LH, FSH, ACTH, T3, T4, TSH, PTH); urine analysis; anti-ganglioside antibodies; anti-Hu, anti-Ri, anti-Yo antibodies. Liquor analysis showed elevated protein level 497.2 mg/L (normal values 130-370), while cell count, chloride, glucose, lactate, as well as S-100 protein were normal. EEG and EMNG analysis were within normal limits. He was anti-HbsAG, anti-HCV and anti-HIV negative. Abdomen ultrasound, X-ray of the coxofemoral joints, MSCT of the thorax and brain MRI were without any pathologic findings. Neuropsychologic evaluation showed anxiety, elevated psychomotor tension which was projected on physical plan with lowered mental efficacy. Later, when elevated titer of anti-CASPR2 antibodies were found, the diagnosis was introduced. He was treated with carbamazepine without any improvement in clinical symptoms. We proceed with plasmapheresis (5 treatments) and many symptoms diminished so patient was discharged without any psychopathologic phenomena or vegetative symptoms, and with no low back pain.