Introduction
Polyneuropathy related pain (PP) is often encountered problem. Despite many medications, it is challenging to the treat PP.
Of the existing methods, sympathetic ganglion block (SGB) is known to reduce pain. But blocking effect is temporary in most patients. By repeating SGB or using neurodestructive material can make effect longer. However, complications can occur.
Not like neurodestructive material, botulinum toxin (BT) inhibits the release of acetylcholine from cholinergic nerve endings and typically used for dystonia. Sympathetic blocking effect can be obtained by directly inject BT at the sympathetic ganglion. Also there are several reports about prolonged sympathetic blocking effect of SGB using BT.
So we hypothesized that if patients have effect of SGB with local anesthetics and steroid, SGB with BT can relief PP much longer.
Case report
A 48 years old man with Eosinophilic Granulomatous polyangitis (EGPA) was referred to our Department about both feet tingling sensation for 1 month. Both feet pain was started with both leg edema and purpura, without trauma. Pain was tingling nature [VAS 8]. After admission, he was diagnosed with EGPA. Also they did Nerve Conduction Velocity test (NCV) and findings are suggesting bilateral peroneal and tibial neuropathy. Despite the use of steroid, gabapentin and pregabalin, both feet pain didn’t subside and he can’t walk and sleep.
After referred to us, we assumed that his foot pain can be improved by Lumbar SGB (LSGB). So we did Both L2 LSGB with steroid and local anesthetics. After both LSGB, both feet pain was improved but didn’t last long. So 2 weeks later, we did both LSGB with BT 50units on each side. After injection, both feet pain and neuropathic pain were decreased from vas 8 to 3 and maintained for a month.
Discussion
PP is challenging to the treat. If PP didn’t relived by medications, sympathetic block can be helpful.
There are several studies reporting pain relieving effect of SGB. But the blocking effect is temporary in most case. Repeating SGB with local anesthetics or neurodestructive procedures can be a option for longer effect.
BT is commonly used for focal dystonia. BT can block releasing acetylcholine at pre-synaptic nerve terminals. Recently many studies report SGB with BT can relief various kind of pain and also effect last for at least 1 month.
In this case report, patients have intractable both feet pain despite using various medications. So we did both LSGB with local anesthetic agent and steroid, and pain was improved but after 1 week, pain recurred. For longer effect, we did Both LSGB with BT and effect both feet pain and neuropathic pain were decreased from vas 8 to 3 and maintained for a month.
According to this case, We report that SGB using BT could be helpful if PP caused by EGPA has not improved despite drug use. |
