E–F

end-stage renal disease (ESRD) A condition of
permanent RENAL FAILUREin which the KIDNEYScan
no longer function to filter wastes from the BLOOD.
People who have ESRD require ongoing RENAL
DIALYSISand may be appropriate candidates for KID-
NEY TRANSPLANTATION. DIABETES, HYPERTENSION(high
BLOOD PRESSURE), andGLOMERULONEPHRITISare the
most common causes of ESRD in the United
States. About 300,000 Americans live with ESRD,
about 15,000 of whom undergo kidney transplan-
tation each year. ESRD typically follows a period
of chronic renal failure that extends for years to
several decades. More than 40 percent of Ameri-
cans who have ESRD are between the ages of 45
to 64.
About a third of people who have ESRD sur-
vive five years on renal dialysis, whereas 80 to 90
percent who receive transplanted kidneys live five
years after the transplant operation, the five-year
marker being a key assessment point for the suc-
cess of treatment. The waiting list for a cadaver
donor kidney (a kidney donated after a person’s
death) varies widely because donors and recipi-
ents must match, and it can be two or three years
before one receives a kidney because the supply of
donor organs is so limited. An increasingly popu-
lar option is living donor transplantation, in which
a person (often a family member) who provides a
close match for BLOOD TYPEand blood antigens and
has two healthy kidneys donates one kidney for
transplantation into the person who has ESRD.
Each year in the United States nearly 80,000 peo-
ple die from ESRD.
The U.S. federal government’s health-care pro-
gram for older Americans, Medicare, extends cov-
erage to those of any age who have ESRD.
Medicare covers many though not all the costs of
renal dialysis and kidney transplantation. Private

health insurance and state-funded programs may

provide further benefits for those who qualify.

See also MEDICARE COVERAGE FOR PERMANENT

RENAL FAILURE; ORGAN TRANSPLANTATION; SURGERY BEN-

EFIT AND RISK ASSESSMENT.

enuresis An inability to hold the URINE, particu-

larly at night (nocturnal enuresis). A common

term for enuresis is bedwetting. Enuresis is prima-

rily a condition of childhood though may persist

into adulthood, depending on the cause and treat-

ment efforts. About 85 percent of children are

developmentally mature enough to master volun-

tary control of the bladder sphincter between the

ages of 3 and 6. Generally enuresis that persists

beyond the age of 12 is either secondary to other

physical conditions or psychological in origin.

Enuresis is more common among boys.

Conditions commonly associated with enuresis

include CYSTITIS, NEUROGENIC BLADDER, and urethral

obstruction such as CONGENITAL ANOMALY or

obstructive calcifications. Occasionally the cause is

damage to the lower SPINAL CORDor to the SPINAL

NERVESthat control BLADDERfunction. In teens or

adults who develop enuresis, the enuresis may be

an early sign of DIABETESor indicate other health

conditions such as OBSTRUCTIVE SLEEP APNEA(which

disrupts the body’s normal sleep rhythms), SEIZURE

DISORDERS, or HYPERTHYROIDISM(overactive THYROID

GLAND). Obstructive sleep apnea may also be a fac-

tor in children between the ages of two and five

who have enlarged adenoids, which is a common

circumstance among this age group, that block the

back of the throat when lying down. Research in

the late 1990s suggests some people who have

enuresis experience dysfunction of the neurologic

interactions that regulate the depth of sleep and

initiate sleep arousal.

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