Dear Pain Matters blog readers,
Here is an interesting case:
Primary Erythromelalgia Treated with Intrathecal Ziconotide:
A 31-year old woman suffered from primary erythromelalgia for most of her life. Symptoms included:
- Painful reddish skin and swelling in both feet and lower legs;
- Loss of vision in right eye and severely impaired vision in left eye (due to bilateral congenital glaucoma, exophthalmos/abnormally protruding eyeballs and megalocornea);
- Constant erythema and excessively warm lower legs;
- Severe pain including:
- Intense burning throughout both the lower legs;
- Allodynia near the perimalleolar regions in both ankles; and
- Hyperalgesia in bilateral gastrocnemius and instep (arched part of feet).
Physical examination confirmed warmer skin temperatures in the lower legs, very strong burning pain (10/10, when lying very still) and swollen ankles. The skin on her feet was thickened, red and ulcerated, due to her habit of immersing her feet in cold water as often as possible (as part of self-medication). Refer to (a) in first photo.
March 2010 –
After trying ‘almost everything’, a decision was made to trial and implant an intrathecal pump drug delivery system in March 2010.
A low titration schedule from 0.3 mcg/die to 1.2 mcg/die of ziconotide was commenced. This resulted in complete resolution of both allodynia and hyperalgesia.
Dosage was increased to 1.8 mcg/die.
It is noteworthy that the severe swelling and oedema in both lower legs and feet was significantly improved after 1 week of ziconotide treatment. Refer to (b) in first photo.
Source: Russo et al, 2015
April 2013 (3 Years Later) –
In April 2013, the patient presented 4 days late for pump recharging. This delay resulted in both legs and feet being swollen with burning pain. Refer to (a) in below photo.
Following (4-day-delayed) refill, her legs and feet were no longer swollen 2 days later, and there was nil burning pain 1 week later. Refer to (b) in below photo.
Source: Russo et al, 2015
The woman no longer had to immerse her feet in cold water resulting in improved skin appearance. She was able to rest in a bed now (instead of staying up in a chair for months). Overall, ongoing intrathecal ziconotide treatment offered an improved quality of life for the patient.
Long-term use of intrathecal ziconotide does not lead to addiction or tolerance.
Ziconotide exerts its analgesic effects by potently and selectively blocking neuronal N-type voltage-sensitive calcium channels at the presynaptic level, hence inhibiting neurotransmitter release.
It is promising to see that severe pain including burning pain, hyperalgesia and allodynia, as well as swelling, redness and excessive warmth of lower legs and feet in patients with primary erythromelalgia may be managed by intrathecal ziconotide treatment in some cases.
“Sedare dolorem divinum opus est”
“It is divine to alleviate pain”
Galen, 130-200 C.E.
Russo R, Caroleo MC, Cione E, Perri M, Paparo MT, Russo A.
Dual Effect of Ziconotide in Primary Erythromelalgia.
Case Reports in Medicine (2015); Volume 2015, Article ID 592170, 4 pages.