Charcot's triad refers to sets of three of symptoms that characterize a pair of diseases. The neurological Charcot's triad, consisting of nystagmus, intention tremor, and staccato or scanning speech, points to a diagnosis of multiple sclerosis. Alternatively, when referring to gastrointestinal illness, Charcot's triad refers to the combination of right upper quadrant abdominal pain, fever, and jaundice. In these cases, Charcot's triad increases the likelihood that the patient has cholangitis, an infection of the bile ducts. Neither triad, however, invariably guarantees the diagnosis, since other diseases may produce the same symptoms.
Multiple sclerosis is a progressive, degenerative neurologic disease in which the myelin sheaths that normally surround and insulate nerves begin to break down. Nerves cannot properly transmit electrical impulses without the normal myelin sheath. The symptoms of Charcot's triad occur as a result of myelin degeneration. Nystagmus is a jerky, rhythmic, involuntary eye movement, while intention tremor is a tremor that intensifies when the patient is deliberately attempting to use an extremity. Staccato speech is speech in which each syllable is enunciated separately, while scanning speech is slurred and droning in quality.
Bile is a body fluid produced by the liver that aids digestion. Cholangitis is an infection of the duct or tube that transports bile to the gallbladder and intestines. If the bile duct becomes obstructed by a gallstone, tumor, or scar tissue, bacteria can cause an infection in the duct, which can subsequently spread to the liver. Jaundice, which is yellowish discoloration of the skin and eyes, happens when the normal excretion of bile is blocked. Fever and right upper quadrant pain occur as the infection develops in the liver and bile duct, which are located in the right upper abdomen. As the patient becomes more ill, hypotension and mental status changes combine with Charcot's triad to make up Reynold's pentad.
Both forms of Charcot's triad are named for Jean-Martin Charcot, a French neurologist who is widely considered to be the originator of modern neurology. One of Charcot's greatest contributions to medical science was his advancement of methodical neurological assessment and the correlation of clinical findings with specific disease entities. Charcot's name is associated with many other medical terms and designations, including Charcot-Bouchard aneurysms, Charcot-Marie-Tooth disease, and Charcot's disease, also known as amyotrophic lateral sclerosis or Lou Gehrig's disease. Charcot also first described the Charcot joint, which is a weight-bearing joint that has degenerated due to loss of peripheral nerve sensitivity.