Pain is a very complex topic! Our sensory (taste, seeing, touch & feel, smell, & hearing) signals detected by all of these various nerves all end up in the brain where they must be interpreted: "Ouch! That felt like a fire ant bite!" The same brain that interprets is the same brain that becomes troubled by stress, fear, and anxiety. So, physical and emotional "wires can get crossed".

Crossed wires can also be crossed just in the physical aspect: "referred pain". That is, some pain-provoking physical abnormality below the skin surface can have us "feel like" the pain is somewhere else. With sciatica, the nerve to the upper back of a leg may be pinched where it exits the back bone, but you "feel the pain" [your brain interprets the pain] as running down the back of your leg. The most extreme example is phantom pain syndrome in which irritation at the sight of the severed nerves of a leg amputated above the knee cause it to "feel like" the absent big toe, for example, is hurting.

Somewhat similarly, psychological stress, strain, anxiety and pain can come out as all sorts of psychosomatic ("supratentorial") illnesses such as pain syndromes, allergic reactions, weight loss, and fatigue. Such syndromes may also be referred to as "functional disorders" or "psychological disorders" or ""psychogenic disorders". Due to sudden situations involving relationships or spiritual issues...or even various intense issues as far back as childhood...the patient may begin to experience physical problems which are "as real as it gets".

Since pain involves "the mind", getting to the root of pain problems is a very tricky business!! For example, the source of a reason for a psychosomatic pain problem is most often not even consciously known by the patient. So, your treating doctor may have to sort through trial & error to first separate out any actual physical causes. Biopsies may be a part of such a work up, especially in the GI area...for example, esophageal biopsies in the course of a chest pain work up.

Chest pain:

1. precordial catch syndrome (PCS): common & feels like from a very vague almost unnoticeable twinge of pain in the left chest just over the heart to a sharper pain in the same area.
2. gastroesophageal reflux disorder (GERD): related to acid stomach contents burping or pushing up into the esophagus.
3. gallbladder aches & pains: from either abnormal squeezing in response to food (biliary dyskinesia) or stones (cholelithiasis) or inflammation (cholecystitis).
4. angina (heart pain due to too little blood flow):

Abdominal pain:

1. heavy metal poisoning: burning pain, evidence of peripheral neuropathy (burning feet, hands, skin; numbness): EGD exam may show red mucosa  & biopsy "reactive gastropathy"; diagnosed with 24 hour urine collection and analysis for heavy metals.

2. abdominal migraine: EGD exam usually negative.

3. superior mesenteric artery syndrome: pain usually after meals; EGD exam usually negative.

4. hyperparathyroidism: blood calcium levels usually abnormal.

5. "shingles" (herpes zoster)...postherpetic (VZV) neuralgia (PHN)...skin findings may be absent.

6. black widow spider bite: relatively innocuous bite may almost go unnoticed; then acute onset of abdominal pain wiith board-like abdomin and an elevated blood pressure which pain is relieved by IV injection of calcium.

7. acute intermittent porphyria: 95% are erythroid type & 5% non-erythroid; blood test for PBG-deaminase will be low in the former but not necessarily in the 5% (but, in just population screening, the vast majority of instances of low PBG-deaminase are not AIP...so a low level is not diagnostic). A 24-hour urine test [CP07-17] collected in opaque container (protect from sunlight), clean catch & without preservative or chemicals, & keep specimen refrigerated (or ice slush in a cooler) at all times and direct lab that it must be kept refrigerated...test for PBG & delta ALA. Unless pain episode VERY remote, eryhtroid AIP should have an elevated urine PBG. Also use this specimen when 24 hour urine porphyrins are tested.

8. common causes usually diagnosed by doctor exam plus radiology imaging: stomach dyspepsia, gallbladder problems, ulcers, small bowel infections & lesions (don't forget celiac disease), appendix lesions, & colonic lesions...as well as irritable bowel syndrome (IBS).

Headache (cephalgia), earache (otalgia), toothache (odontalgia): the head is notorious for "referred pain"...the pain sensation is in one site but the cause in another.

1. tension

2. cluster

3. migraine

4. arising from sinus pain: pain over a sinus area or referred into a tooth area.

5. ear pain & otoscopic exam normal: referred pain from orophanygeal mass, irritated eustachian tube, toothache.

6. arising from skin pain...for example, shingles (may not have skin findings)

7. head/face/jaw: trigeminal neuralgia

8. "Benign paroxysmal cranial neuralgia" or "cephalgia fugax"...brief shooting head pains

9. brain tumor or aneurysm

10. other central (CNS) or peripheral nerve injury or lesion

Neck and back pain & sciatica:

1. organic back: HERE...and especially see link #3 at bottom of that page.
2. psychosomatic: I suspect that chiropractic methods work here. Check this website.

Vulvar/Vaginal:

1. spinal nerve entrapment syndrome

2. vulvodynia: as a pathologist, I have closely known one case, and the vulvodynia left upon the exiting from a disappointing marriage & into a compatible marriage.

3. other central (CNS) or peripheral nerve injury

4. referred pain from a pelvic lesion such as a diverticular abscess

Anus/rectal:

1. proctalgia fugax

2. prostatitis

The above & other sites:

1. primary peripheral nerve injury:

   • peripheral diabetic neuropathy (PDN)

   • alcoholic neuropathy

   • acute inflammatory demyelinating polyradiculoneuropathy

   • HIV-related neuropathy

   • post-herpetic neuralgia

   • trigeminal neuralgia

   • posttraumatic neuralgia

   • radiculopathy caused by spinal osteoarthritis or discopathy

   • postradiation plexopathy

Central (CNS) primary injury:

• thalamic stroke

• compressive myelopathy

References:

(posted 9 August 2004; latest addition 26 May 2008)