上背部の激痛で発症したGuillain-Barré症候群の1例

A Case of Guillain-Barré Syndrome Starting from Severe Upper Back Pain

要旨　症例は58歳女性。上背部の激痛で発症し，四肢のしびれ，左顔面神経麻痺，小脳失調も出現し当科に入院した。腱反射は低下し，髄液検査で蛋白細胞解離を認め，Guillain-Barré syndrome （GBS） と診断した。上背部の激痛に対し，NSAIDs，抗不安薬，非麻薬性鎮痛薬，ステロイドを使用したが無効であり，プロポフォールで鎮静した。その後，四肢の筋力低下と呼吸不全が出現し，人工呼吸器管理とした。免疫グロブリン大量静注療法で全ての症状は改善した。GBSによる痛みは本邦ではあまり注目されていないが，比較的頻度が高く，初発症状であることもある。また難治性の上背部痛をきたすことがあり，GBSの診断および治療に際し注意が必要である。

Examination of a 58-year-old woman who had developed severe upper back pain showed left peripheral type of facial nerve palsy, sensory disturbance of limbs and body trunk （Th7-9）, cerebellar ataxia and generalized hyporeflexia. Upper back pain increased at night and was resistant to NSAIDs, antianxiety agents, opioids, and corticosteroids. Concentrations of serum CK and cerebrospinal fluid total protein were elevated. Electromyography （EMG） of perivertebral muscles （Th7-10） showed reduced recruitment and polyphasic potential. Several days later,our patient developed weakness of limbs and respiratory failure, and required mechanical ventilation. From these findings, we diagnosed her as having Guillain-Barré syndrome （GBS） and began treatment with intravenous immunoglobulin therapy. All symptoms including upper back pain improved gradually, and she had recovered almost completely by the 40th hospitalization day. Pain, especially lower back and leg pain, have attracted attention as common symptoms in GBS. However, only one GBS patient with initial severe upper back pain has been reported. Although the precise mechanism of pain in GBS remains unclear, EMG findings lead us to surmise our patient's pain originated from the nerve roots. Limb and back pain should therefore be taken into account for the diagnosis and treatment of GBS patients.