M–O

Medicare coverage for permanent renal failure
Federal government funding in the United States
that pays for medical treatment for people of any
age who have END-STAGE RENAL DISEASE(ESRD), also
called permanent RENAL FAILURE. Though for other
health conditions an individual must be age 65 or
older to qualify for Medicare coverage, the US
Congress in 1973 passed legislation broadening
Medicare coverage to include care for ESRD at any
age. There are specific eligibility requirements and
co-payments. Health-care providers that offer care
for ESRD have information about the application
and approval processes. The US Centers for
Medicare and Medicaid Services Web site
(www.cms.hhs.gov) also provides comprehensive
information about eligibility and covered services.
See also KIDNEY TRANSPLANTATION; QUALITY OF LIFE;
RENAL DIALYSIS.

micturition See URINATION.

minimal change disease A disorder of kidney
function in which the structure of the KIDNEYS,
notably the nephrons, appears normal with regu-
lar (light) microscope examination though slightly
abnormal with electron microscope examination.
Minimal change disease is primarily a condition of
childhood (usually in children under age six) and
seldom occurs in adults. Researchers believe the
condition is one of immune dysfunction in which
T-cell lymphocytes cause molecular damage to the
delicate walls of the glomeruli. The damage allows
ALBUMIN(protein) to leak from the BLOODinto the
URINE(ALBUMINURIA).

Symptoms and Diagnostic Path

The symptoms of minimal change disease are
often vague and include

• edema, often of the face


• fatigue


• MUSCLE-wasting


• impaired growth


• unexplained weight gain

The diagnostic path begins with urinalysis,

which typically shows albuminuria (albumin

excretion). Other laboratory tests are often nor-

mal. There is a high correlation between minimal

change disease and NEPHROTIC SYNDROME, a constel-

lation of symptoms that indicate kidney dysfunc-

tion. The urologist may recommend a trial of

treatment before conducting further, more inva-

sive diagnostic procedures.

Treatment Options and Outlook

Treatment for minimal change disease is IMMUNO-

SUPPRESSIVE THERAPY with CORTICOSTEROID MEDICA-

TIONSsuch as prednisone. Most children improve

remarkably within two weeks, and nearly all

within six to eight weeks. The nephrologist may

make dietary recommendations to maintain

appropriate protein, sodium, and fluid intake.

Minimal change disease fully resolves, without

residual damage to the kidneys, with treatment in

most children. About 10 percent of children expe-

rience periodic RECURRENCEof symptoms through

ADOLESCENCEand sometimes into adulthood. Chil-

dren taking corticosteroid medications have a

somewhat increased risk for INFECTIONduring the

course of therapy.

Risk Factors and Preventive Measures

Because researchers do not know what causes

minimal change disease, there are no measures to

prevent its occurrence. Prompt treatment mini-

205