GLOSSARY: U TERMS

Uhthoff phenomenon

Acute worsening of multiple sclerosis symptoms on exposure to heat because high body temperatures may exceed the capacitance of the demyelinated nerve and conduction may fail.

Ultrafiltration

The movement of plasma water across a semi permeable membrane.

Ultrasound

An imaging method that uses high frequency sound waves to produce images of structures within the body.

Uncomplicated acid-base disorder

See simple disorder.

Unknown-onset seizures

Seizures where the onset (ie, focal or generalized) cannot be determined.

Unstable angina

Pathogenically similar to non-ST segment myocardial infarction but without muscle damage, therefore, troponins are not elevated.

Uremia

A condition that results from accumulation of metabolic waste products and endogenous toxins in the body resulting from impaired kidney function. Symptoms of uremia include nausea, vomiting, weakness, loss of appetite, and mental confusion.

Urethral structure

Narrowing of the urethra.

Urgency

A compelling desire to void, which is difficult to defer

Uricosuric

Pertaining to, characterized by, or promoting renal excretion of uric acid.

Urosepsis

Sepsis resulting from a urinary source.

Urticaria

Itchy, raised, swollen areas on the skin. Also known as hives.

Uveitis

An inflammation of the uvea. Uveal structures include the iris, the ciliary body, and the choroid.