Diabetic angiopathy
Encyclopedia
Diabetic angiopathy is a form of angiopathy
associated with diabetes mellitus
. While not exclusive, the two most common forms are Diabetic retinopathy
and Diabetic nephropathy
, whose pathophysiologies are largely identical.
, pericytes express enzymes which convert glucose into osmologically-active metabolites such as sorbitol
leading to hypertonic cell lysis.
Over time, pericyte death may result in reduced capillary integrity; subsequently, there is leaking of albumin
and other proteins into fluid compartments. The glomeruli of the kidneys are especially sensitive - see diabetic nephropathy - where protein leakage caused by late-stage angiopathy results in diagnostic proteinuria
and eventually renal failure
. In diabetic retinopathy the end-result is often blindness due to irreversible retinal damage.
in the US, usually toes and feet, often as a result of gangrene
, and almost always as a result of peripheral vascular disease. Retinal damage (from microangiopathy) makes it the most common cause of blindness among non-elderly adults in the US.
Prognosis is generally poor for all forms of Diabetic angiopathy, as symptomatology is tied to the advancement of the underlying pathology i.e. the early-stage patient displays either non-specific symptoms or none at all.
"Diabetic dermopathy
" is a manifestation of diabetic angiopathy. It is often found on the shin.
There is also Neuropathy; also associated with diabetes mellitus; type 1 and 2.
Angiopathy
Angiopathy is the generic term for a disease of the blood vessels . The best known and most prevalent angiopathy is diabetic angiopathy, a common complication of chronic diabetes.-By caliber:...
associated with diabetes mellitus
Diabetes mellitus
Diabetes mellitus, often simply referred to as diabetes, is a group of metabolic diseases in which a person has high blood sugar, either because the body does not produce enough insulin, or because cells do not respond to the insulin that is produced...
. While not exclusive, the two most common forms are Diabetic retinopathy
Diabetic retinopathy
Diabetic retinopathy is retinopathy caused by complications of diabetes mellitus, which can eventually lead to blindness....
and Diabetic nephropathy
Diabetic nephropathy
Diabetic nephropathy , also known as Kimmelstiel-Wilson syndrome, or nodular diabetic glomerulosclerosis and intercapillary glomerulonephritis, is a progressive kidney disease caused by angiopathy of capillaries in the kidney glomeruli. It is characterized by nephrotic syndrome and diffuse...
, whose pathophysiologies are largely identical.
Pathophysiology
As insulin is required for glucose uptake, hyperglycemia in diabetes mellitus does not result in a net increase in intracellular glucose in most cells. However, chronic dysregulated blood glucose in diabetes is toxic to cells of the vascular endothelium which passively assimilate glucose. That is, cells in which insulin is not required for intercellular transport of glucose, most-notably the pericytes of the microvasculature. In addition to direct glucose-induced damage by (e.g.) glycationGlycation
Glycation is the result of the bonding of a protein or lipid molecule with a sugar molecule, such as fructose or glucose, without the controlling action of an enzyme. All blood sugars are reducing molecules. Glycation may occur either inside the body or outside the body...
, pericytes express enzymes which convert glucose into osmologically-active metabolites such as sorbitol
Sorbitol
Sorbitol, also known as glucitol, Sorbogem® and Sorbo®, is a sugar alcohol that the human body metabolizes slowly. It can be obtained by reduction of glucose, changing the aldehyde group to a hydroxyl group. Sorbitol is found in apples, pears, peaches, and prunes...
leading to hypertonic cell lysis.
Over time, pericyte death may result in reduced capillary integrity; subsequently, there is leaking of albumin
Albumin
Albumin refers generally to any protein that is water soluble, which is moderately soluble in concentrated salt solutions, and experiences heat denaturation. They are commonly found in blood plasma, and are unique to other blood proteins in that they are not glycosylated...
and other proteins into fluid compartments. The glomeruli of the kidneys are especially sensitive - see diabetic nephropathy - where protein leakage caused by late-stage angiopathy results in diagnostic proteinuria
Proteinuria
Proteinuria means the presence of anexcess of serum proteins in the urine. The protein in the urine often causes the urine to become foamy, although foamy urine may also be caused by bilirubin in the urine , retrograde ejaculation, pneumaturia due to a fistula, or drugs such as pyridium.- Causes...
and eventually renal failure
Renal failure
Renal failure or kidney failure describes a medical condition in which the kidneys fail to adequately filter toxins and waste products from the blood...
. In diabetic retinopathy the end-result is often blindness due to irreversible retinal damage.
Prognosis and complications
Diabetes mellitus is the most common cause of adult kidney failure worldwide. It also the most common cause of amputationAmputation
Amputation is the removal of a body extremity by trauma, prolonged constriction, or surgery. As a surgical measure, it is used to control pain or a disease process in the affected limb, such as malignancy or gangrene. In some cases, it is carried out on individuals as a preventative surgery for...
in the US, usually toes and feet, often as a result of gangrene
Gangrene
Gangrene is a serious and potentially life-threatening condition that arises when a considerable mass of body tissue dies . This may occur after an injury or infection, or in people suffering from any chronic health problem affecting blood circulation. The primary cause of gangrene is reduced blood...
, and almost always as a result of peripheral vascular disease. Retinal damage (from microangiopathy) makes it the most common cause of blindness among non-elderly adults in the US.
Prognosis is generally poor for all forms of Diabetic angiopathy, as symptomatology is tied to the advancement of the underlying pathology i.e. the early-stage patient displays either non-specific symptoms or none at all.
"Diabetic dermopathy
Dermopathy
Dermopathy can refer to:* Diabetic dermopathy* Graves' dermopathy, or Infiltrative dermopathy* Nephrogenic fibrosing dermopathy * Restrictive dermopathyspecial type of diseases accouting with skin and its underlying layers...
" is a manifestation of diabetic angiopathy. It is often found on the shin.
There is also Neuropathy; also associated with diabetes mellitus; type 1 and 2.