Diabetic Nephropathy Prevention Clinical Approach and Treatment


Recent searches for information in diabetic nephropathy yielded a limited amount of information concerning the disease, its diagnosis and its treatment. What was evident was the fact that it is another concern for those individuals who have been diagnosed with diabetes, and further, that proper (and early) treatment can do much to stop the disease's progression and in many cases will prevent the disease.

Diabetic nephropathy presents itself in individuals with diabetes but it is closely related to nephrolithiasis which is a common condition that affects "nearly five percent of U.S. men and women during their lifetimes" FN1. Nephrolithiasis includes a number of different nephropathy diseases. "Nephrolithiasis specifically refers to calculi in the kidneys (including) both renal calculi ureteral calculi (ureterolithiasis)" FN2 Ureteral calculi almost always originate in the kidneys, although they may continue to grow once they lodge in the ureter. Nephrolithiasis is commonly referred to as kidney stones, but other problems can occur pertaining to the kidney including two of the most prevalent conditions related to nephrolithiasis, which are IgA nephropathy and diabetic nephropathy.

According to the National Kidney and Urologic Diseases Information Clearinghouse (NKUDIC) IgA nephropathy occurs "when IgA - a protein that helps us fight infections - settles in the kidneys" FN3.

Diabetic nephropathy, on the other hand, occurs when there is too much protein and/or blood leaking from the kidney into the blood stream. Many of the symptoms for both diseases are very similar.

Symptoms can include "swelling in the hands and feet, nausea, fatigue, headaches, and sleep problems" FN3.

Approximately 20-30% of individuals with diabetic nephropathy suffer kidney failure while 25% of IgA nephropathy sufferers will suffer kidney failure within 10 to 20 years of diagnosis. Nephrolithiasis produces a calculi that can "be prevented in most patients by the use of a simplified evaluation, reasonable dietary and fluid recommendations, and directed pharmacologic intervention" FN1.

Diabetic nephropathy is normally referred to as diabetic kidney disease and it can lead to kidney failure. "Diabetic nephropathy presents in its earliest stage with low levels of albumin (microalbuminuria) in the urine" FN4. Low levels of albumin can be detected by a number of methods with three of the most common being; a spot urine test, a 24-hour urine sample and a three to six-month urine sample. "The most practical method of screening for microalbuminuria is to assess the albuminto-creatinine ratio with a spot urine test" FN4.

Once the diagnosis has been made early treatment can help to control the progress of the disease and many times will stave off kidney failure for a number of years. Thorp's study showed that "there is good evidence that early treatment delays or prevents the onset of diabetic nephropathy, or diabetic kidney disease" FN4. Early treatments can include a change in diet, exercise, improved blood sugar control, pharmaceuticals and even a regime of vitamins.

A team of investigators for the journal Diabetes Care "demonstrated that vitamin sC and E, along with mineral supplementation (including magnesium) appear to improve kidney function in patients with type 2 diabetes and proved useful in addressing a common complication call diabetic nephropathy" FN5. Treatments for nephrolithiasis can also be helpful for diabetic nephropathy patients. Many physicians will recommend "aggressive fluid intake and moderated intake of salt, calcium, and meat for most patients" FN6. American Family Physicians also reports that allopurinol can be helpful and using inhibitors can help break the cycle of infectious calculi in the kidney. In fact, evidence from Pietrow's 2006 study indicates that "increased water intake reduces the risk of recurrence of urinary calculi and prolongs the average interval between recurrences" FN1. Pietrow also showed that "recurrent calculi can be prevented in most patients by the use of a simplified evaluation, reasonable dietary and fluid recommendations, and directed pharmacologic intervention" FN1.

One of the reasons why it is important to have early diagnosis and treatment of not only diabetic nephropathy but all kidney diseases is that it can drastically affect a large number of individuals. Diabetes is one of the most prevalent diseases in America and the majority of these individuals will experience some form of kidney disease during their lifetime. One study showed that "within two to three decades of diagnosis, roughly one third of patients with diabetes will have some degree of diabetic kidney disease" FN7.

One way to address the possibility of kidney disease even before it has presented in a patient, is by ensuring that the patient control blood glucose levels, maintain a healthy lifestyle, and observe the practices necessary to regulate blood pressure and hypertension. According to a recent article in the American Family Physician journal, "many physicians in family practices and community-based clinics need to have an organized system of regular follow-up and review of patients with hypertension" FN8.

Reasoning behind this type of assertion is that hypertension is a precursor of kidney disease especially in regards to individuals suffering from diabetes. The same article states that "antihypertensive drug therapy should be implemented by means of a vigorous, stepped care approach when patients do not reach target blood pressure levels" FN8. Targeting blood pressure levels, hypertension and controlling glucose levels is important because "diabetes has become the leading cause of end-stage renal disease in the United States" FN9.

One method for ensuring that diseases such as diabetic nephropathy does not overwhelm the medical community or the individuals suffering from those diseases is by continuing to implement preventive medicines. One of the methods that has been most efficient in controlling the diabetic's glucose levels is by the injecting of insulin. This is the most common method of controlling glucose and the hassle of injecting oneself on a daily basis has now been enhanced. Patients needing insulin can now administer the medicine through inhalation procedures.

Recent studies that have been published in the Annals of Internal Medicine provided findings that "researchers noted a significant improvement in sugar control...by adding inhaled insulin therapy (currently awaiting FDA approval) to the diabetic regimen" FN5. In the article, Julio Rosenstock, M.D., from the Dallas Diabetes and Endocrine Center at Medical City states "patients with type 2 diabetes who do not achieve glycemic control with oral therapy eventually require insulin. Compared with injected regular insulin, inhaled insulin is more rapidly absorbed and eliminated and has a more rapid glucose-lowering effect" FN5.

Controlling glucose levels is an important aspect to preventing kidney disease and regular monitoring of those levels is of equal importance. Also important is the monitoring of the diabetic's A1C levels. Screening for microalbuminuria is also an important consideration in determining whether a diabetic is showing symptoms of kidney disease. According to Micah L. Thorp, D.O., M.P.H., Lake Road Nephrology Clinic, "the most practical method of screening for microalbuminuria is to assess the albumin-to-creatinine ratio with a spot urine test" FN4. Thorp asserts that results of two or three of these screenings for microalbuminuria should be more than 30 mg per day or 20 meg per minute in a three- to six-month period. Similar results such as these are useful in diagnosing diabetic nephropathy. At its earliest stages diabetic nephropathy presents with low-level albumin which increases until the patient develops overt nephropathy. When the patient has reached this level, a problem develops that can be overlooked by the diagnosing physician.

The problem is that overt nephropathy often coincides with a high-filter period when both the creatinine clearance and glomerular filtration rates are high. According to Thorp this is the point when deception is high as well. The elevated clearance is replaced by a decrease in glomerular filtration that may ultimately lead to kidney failure FN4. Other interventions can be implemented that will slow the onslaught of kidney disease. Besides those mentioned above (i.e., regulating blood pressure and glucose levels) other important interventions such as "lowering low-density lipoprotein cholesterol, aspirin therapy, influenza vaccination...are recommended for patients with diabetes, even those with A1C levels less than seven percent" FN10. When the patient reaches the overt nephropathy stage screening is no longer necessary when looking for microalbuminuria. The reason for this is because there is a high enough level of protein in the urine to be detected on a routine urinanalysis.

Just as there is no cure for diabetes, there also is no cure for diabetic kidney disease. This does not mean that every diabetic patient with high microalbuminuria will experience diabetic nephropathy, and in fact, some recent studies have show that "patients with low systolic blood pressure, low levels of cholesterol, and low levels of glycosylated hemoglobin were more likely to experience regression" FN4 after being diagnosed with high microalbuminuria levels. Previous studies have also shown the effectiveness of prescribing an angiotension-converting enzyme (ACE) inhibitor or an angiotensin receptor blocker (ARB).

One recent study concluded that "compared with placebo or controls, angiotensin-converting enzyme (ACE) inhibitors (captopril, lisinopril, enalapril, perindopril, and ramipril) reduced progression to microalbuminuria and increased regression to normoalbumin-uria in normotensive persons with type 1 diabetes and microalbuminuria" FN11.

Physicians should be aware, however, that introducing ACE inhibitors can sometimes trigger acute episodes of…