Phantom organ pain: a myth or a clinical entity

Abstract

Phantom organ pain syndrome occurs presumably due to injury to the visceral sensory nerves innervating the missing organ. The pain has been attributed to deafferentation due to surgical trauma to the incision site, to deep somatic nerves, to mononeuropathy, or to the possibility of phantom organ pain syndrome. We present a case of a man with chronic left flank pain and pyelonephritis despite ongoing therapy with antibiotics and hydrocodone. Ultimately, a left-sided nephrectomy was performed which resolved his chronic infection but did not minimize his chronic flank pain. Postsurgical imaging included a negative MRI, CT, and ultrasound of his abdomen and pelvis. To determine an optimal treatment plan for our case patient, a literature search for "phantom organ," "phantom pain," and "phantom limb" was undertaken. The following medical databases were used: PubMed, Cochrane Library, MD Consult, Ovid, Google and Google Scholar, Medscape, and UpToDate. Over 100 articles written in English were reviewed, and a total of 36 articles were determined to be clinically relevant to our patient. Only 3 of the 36 aforementioned articles discussed phantom organ pain directly, but no specific treatment for phantom organ pain was described. Multiple treatment options for phantom pain in general were discussed in the reviewed articles. Pharmacologic treatment agents included NSAIDs, narcotics, NMDA antagonists, GABA analogs, anticonvulsants, antidepressants, and muscle relaxants. Interventional treatments included nerve blocks, neurolysis, sympathectomy, spinal cord stimulators, deep brain stimulators, TENS units, and even cortical brain resection. Other significant treatments included rehabilitation and physical therapy, mirror therapy, electromyographic and thermal biofeedback, acupuncture, psychological treatments, and hypnosis. Our case patient was started on low-dose gabapentin and currently very well controlled without narcotics on Gabapentin 600 mg TID and supportive psychotherapy. More research in the field of phantom organ and phantom limb pain is needed to treat this complex disease process.