Page 677 - Fundamentals of anatomy physiology

Spotlight Figure 18–18 Retinal Damage
Diabetes Mellitus The proliferation of capillaries
and hemorrhaging at the retina
Untreated diabetes mellitus disrupts metabolic activities may cause partial or complete
throughout the body. Clinical problems arise because the tissues blindness. This condition is
involved are experiencing an energy crisis—in essence, most called diabetic retinopathy.
of the tissues are responding as they would during chronic
starvation, breaking down lipids and even proteins Early Heart Attacks
because they are unable to absorb glucose from their Degenerative blockages in
surroundings. Problems involving abnormal cardiac circulation can lead to
changes in blood vessel structure are early heart attacks. For a given
particularly dangerous. An estimated 25.8 age group, heart attacks are
million people in the United States have three to five times more likely
some form of diabetes. in people with diabetes than in
nondiabetic people.
Kidney Degeneration
Degenerative changes in the Peripheral Nerve Problems
kidneys, a condition called Abnormal blood flow to neural
diabetic nephropathy, can tissues is probably responsible
lead to kidney failure. for a variety of neural problems
with peripheral nerves,
Diabetes Mellitus including abnormal autonomic
function. These disorders are
Diabetes mellitus (mel-Ī-tus; mellitum, honey), is characterized by glucose collectively termed diabetic
concentrations that are high enough to overwhelm the reabsorption neuropathies.
capabilities of the kidneys. (The presence of abnormally high glucose levels
in the blood in general is called hyperglycemia [hī-per-glī-SĒ-mē-ah].) Peripheral Tissue Damage
Glucose appears in the urine (glycosuria; glī-kō-SYŪ-rē-a), and urine Blood flow to the distal portions
volume generally becomes excessive (polyuria). of the limbs is reduced, and
peripheral tissues may suffer as
subdivided into a result. For example, a
reduction in blood flow to the
Type 1 Diabetes Type 2 Diabetes feet can lead to tissue death,
ulceration, infection, and loss of
Type 1 is characterized by Type 2 is the most common form toes or a major portion of one
inadequate insulin production of diabetes mellitus. Most people or both feet.
by the pancreatic beta cells. with this form of diabetes
Persons with Type 1 diabetes produce normal amounts of
require insulin to live and insulin, at least initially, but their
usually require multiple tissues do not respond properly,
injections daily, or continuous a condition known as insulin
infusion through an insulin resistance. Type 2 diabetes is
pump or other device. This associated with obesity, and
form of diabetes accounts for weight loss through diet and
approximately 5% of cases. It exercise can be an effective
usually develops in children treatment, especially when
and young adults. coupled with oral medicines.

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