When patients are first diagnosed with kidney disease, they are often overwhelmed by the sheer amount of information they have to learn. Renal disease is complicated because impairment of the kidneys affects many different systems of the body and can result in hypertension, anemia and bone problems. These issues go far beyond filtration of blood, which is one of the kidneys' main functions.
The chief feature of the kidneys are the various vascular structures from which they are made. The complicated network of veins, arteries and capillaries that carry the blood are all part of the vascular system. Much of the tissue of the kidneys is made from arteries and capillaries, such as the large renal artery that brings blood to the kidneys and the tiny capillaries called glomeruli that filter the blood.
According to The National Institutes of Diabetes, Digestive and Kidney Disease, patients with advanced kidney disease are often anemic because because their scarred kidneys lose their ability to work effectively with the endocrine system.
The endocrine system refers to the collection of chemical messengers called hormones that are released into the blood stream. The kidneys are also part of the endocrine system because they release a hormone called erythropoitin--abbreviated EPO-- which is responsible for transforming reticulocytes into mature iron-bearing red blood cells.
Regular injections of synthetic EPO can be very helpful for anemic kidney patients.
More Expert Insight
The Family Practice Notebook explains that the renin-angiotensin system (RAS) is part of the endocrine system involved in the regulation of blood pressure. The kidneys secrete an enzyme called renin, which converts angiotensin to angiotension I, which in turn is converted into angiotensin II. Angiotensin II is directly involved in the regulation of blood pressure.
When kidneys become scarred, they sense less blood flowing through them, so they secrete more renin, which in turn causes more production of angiotensin II. Angiotensin II constricts blood vessels, causing an increase in blood pressure.
Since hypertension destroys kidney disease, the involvement of the RAS creates a vicious cycle that can be difficult to control.
Elevated levels of phosphorus in kidney patients indirectly cause the skeletal system to become weakened.
Impaired kidneys lose the ability to remove phosphorus from the blood which causes serum phosphorus levels to increase. Since phosphorus is involved in the regulation of calcium, high blood levels of phosphorus cause calcium to drop. If calcium levels drop, the parathyroid glands in the neck secrete parathyroid hormone which pulls calcium from the bones to compensate. This gradually and silently weakens the bones.
The National Institute of Diabetes, Digestive and Kidney Disease explains that the effects of kidney disease on the skeletal system are called renal osteodystrophy.
Monitoring and Treatment
Regardless whether they involves hypertension, bone strength, anemia or something else, symptoms caused by kidney failure are managed by a nephrologist. The nephrologist monitors blood pressure, red blood cell counts, phosphorus levels, parathyroid hormone levels and other aspects of kidney disease. Maintaining a close relationship with the nephrologist is critical so that problems are identified and treated appropriately regardless what body system is involved.