Sensitization of the nervous system can occur without an obvious precipitating cause, e.g., fibromyalgia, or chronic headache.

In many patients, chronic pain becomes a distinct disease unto itself.

The pain-generating mechanism is often difficult or impossible to determine with certainty; such patients are demanding of the physician’s time and often appear emotionally distraught.

●Neuropathic pain (either peripheral, including post-herpetic neuralgia, diabetic neuropathy; or central, including post-stroke pain or multiple sclerosis)

●Musculoskeletal pain (eg, back pain, myofascial pain syndrome, ankle pain)

●Inflammatory pain (eg, inflammatory arthropathies, infection)

●Mechanical/compressive pain (eg, renal calculi, visceral pain from expanding tumor masses)

Note that these categories are not entirely mutually exclusive, since back pain might be considered both musculoskeletal and mechanical/compressive if it results from nerve root compression.




The problem is often difficult to diagnose with certainty, and pts may appear emotionally distraught.

Several factors can cause, perpetuate, or exacerbate chronic pain:

(1) painful disease for which there is no cure (e.g., arthritis, cancer, chronic daily headaches, diabetic neuropathy);

(2) perpetuating factors initiated by a bodily disease that persist after the disease has resolved (e.g., damaged sensory or sympathetic nerves);

(3) psychological conditions.

Pay special attention to the medical history and to depression.

Major depression is common, treatable, and potentially fatal (suicide).


Managing patients with chronic pain is intellectually and emotionally challenging.

The traditional medical approach of seeking an obscure organic pathology is usually unhelpful. On the other hand, psychological evaluation and behaviorally based treatment paradigms are frequently helpful, particularly in the setting of a multidisciplinary pain-management center. Unfortunately, this approach, while effective, remains largely underused in current medical practice.



Most people with pyelonephritis do not have complications if appropriately treated with bacteria-fighting medications called antibiotics.

In rare cases, pyelonephritis may cause permanent kidney scars, which can lead to chronic kidney disease, high blood pressure, and kidney failure. These problems usually occur in people with a structural problem in the urinary tract, kidney disease from other causes, or repeated episodes of pyelonephritis.

Infection in the kidneys may spread to the bloodstream—a serious condition called sepsis—though this is also uncommon.



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