CHRONIC KIDNEY DISEASE

DEFINITION
Chronic kidney disease is kidney damage or a decrease in renal physiology, more or equal to three months prior to diagnosis. As per the recommendations of the NKF-DOQI (The National Kidney Foundation Disease Outcomes Quality Initiative) (2002):


1.    Kidney damage for ≥ 3 months.The meaning there is kidney damage, is found when structural abnormalities or renal function with or without decreased GFR, with one of the manifestations:
- Abnormalities pathology, or
- Alert kidney damage, including abnormalities of blood or urine composition, or radiological abnormalities
2. GFR <60ml/men/1, 73 m2 ≥ 3 months with or without kidney damage.

           GFR <60ml/men/1, 73 m2 ≥ 3 months, classified as CKD regardless of the presence or absence of renal damage because of the level or lower GFR, renal function had lost ≥ 50% and there are complications. On the other hand the existence of kidney damage regardless of the level of GFR is also classified as CKD. In most cases, renal biopsy is rarely performed, so that renal damage is based on the presence of several markers such as proteinuria, abnormal sediment (hematuria, pyuria with a cast), blood disorders are pathognomonic for renal disorders, such as tubular syndrome (eg renal tubular acidosis, diabetes insipidus nephrogenic), and the presence of abnormal radiological images, such as hydronephrosis.

STADIUM

To determine the stage of CKD, need to estimate GFR. Two commonly used formula to estimate GFR, shown below, and combining plasma creatinine concentration was measured, age, gender, and ethnic origin. Now, many laboratories report estimated GFR, or "e-GFR," using one equation.

1. Equation of a study on the modification of diet in renal disease

Estimated GFR (mL / min per 1.73 m 2) = 1.86 x (PCR) -1.154 x (age) -0.203

Note: Multiply by 0.742 for women

          Multiply by 1.21 for African Americans

2. Cockcroft-Gault formula

                                                        (140-age) x body weight   X (0.85 if female)

Creatinine clearance (ml / min.) =                      72 x serum creatinine                     

                                                           

Stadium    Description    GFR (ml/men/1,73 m2)

1    Kidney damage with normal or increased GFR    ≥ 90

2    Kidney damage with mild decrease in GFR    60-89

3    moderate decrease in GFR    30-59

4    Severe decrease in GFR    15-29

5    Kidney failure    < 15 or dialysis

Decrease the annual average of normal GFR, with the age of peak GFR (~ 120 ml / min per 1.73 m2) 'achieved during the third decade of life, is 1 mL / min per 1.73 m2 per year, reaching an average value of 70 ml / min per 1.73 m2 ~ at age 70. Mean GFR was lower in women than in men. For example, a woman 80's with a normal serum creatinine may have a GFR of only 50 mL / min per 1.73 m2. Thus, even a mild elevation of serum creatinine concentration for example, 130 mol / L (1.5 mg / dL)], often indicating a substantial reduction in GFR in some individuals.

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Measurement of albuminuria is also useful for monitoring the nephron injury and response to therapy in various forms of CKD, particularly chronic glomerular disease. While the capacity of the 24-hour urine accurate is the "gold standard" for measurement of albuminuria, the measurement of albumin-creatinine ratio in morning urine samples is often more practical to obtain and correlate well but not perfectly, with 24-hour urine. The value remains in the urine> 17 mg albumin per gram of creatinine in adult men and 25 mg albumin per gram of creatinine in adult women usually indicate chronic kidney damage. Microalbuminuria refers to excretion of albumin in the amount too small to be detected by conventional measures stick urine or urine protein. This is a good screening test for early detection of kidney disease, in particular, and may be a marker for the presence of microvascular disease in general. If a patient has a large amount of albumin excreted, there is no reason to do a test for microalbuminuria.

Stage 1 and 2 of CKD are usually not associated with symptoms arising from the reduction in GFR. However, there may be a symptom of kidney disease itself, such as edema in patients with nephrotic syndrome or signs of hypertension secondary to renal parenchymal disease in patients with polycystic kidney disease, some forms of glomerulonephritis, and many renal parenchyma and other vascular diseases, even with well-preserved GFR. If the decrease in GFR progressed to stage 3, and 4 clinical and laboratory CKD complications become more prominent. Nearly all organ systems are affected, but the most obvious complications, including anemia and related fatigue easily; decreased appetite with progressive malnutrition, abnormalities in calcium, phosphorus, and mineral regulatory hormones, such as 1,25 (OH) 2D3 (calcitriol) and parathyroid hormone (PTH), and abnormalities in sodium, potassium, water, and acid-base homeostasis. If patients progressed to stage 5 CKD, toxins accumulate so that patients usually experience a marked impairment in their daily activities, welfare, nutrition, and water and electrolyte homeostasis, especially in the uremic syndrome. As discussed above, this situation will lead to death unless treated with renal replacement (dialysis or transplantation).

Etiology and Risk Factors

Aetiology CKD varies greatly from country to country. The main causes of CKD in the United States (1995-1999) are:

a.    Diabetes mellitus (44%)

- Type 1 (7%)

- Type 2 (37%)

b. Hypertension and vascular disease large (27%)

c. Glomerulonephritis (10%)

d. Interstitial nephritis (4%)

e. Polycystic kidney disease (3%)

f. Systemic disease (eg, lupus and vasculitis) (2%)

g. Neoplasms (2%)

h. No known cause (4%)

Until the year 2009, in the United States, diabetes mellitus and hypertension is still a major cause of CKD. According to the Nephrology Association of Indonesia (Pernefri) in 2000 recorded the cause of renal failure undergoing hemodialysis in Indonesia, namely:

a. Glomerulonephritis 46.39%

b. Diabetes mellitus 18.65%

c. Obstruction and infection of 12.85%

d. Hypertension 8.46%

e. Other reasons (polycystic kidney, interstitial nephritis, nephrolithiasis, and idiopathic) 13.65%

The most common causes of CKD are diabetic nephropathy, most often secondary for type 2 diabetes mellitus. Hypertensive nephropathy is a common cause of CKD in the elderly, where chronic renal ischemia as a result of renovascular disease of small and large vessels can be underrecognized. Nephrosclerosis progressive of renal vascular disease are correlated the same process that causes coronary heart disease and cerebrovascular disease. The increasing incidence of CKD in the elderly has been ascribed, in part, to reduced mortality from heart and brain complications of atherosclerotic vascular disease in these individuals, which allows a large segment of the population to realize the components common renal vascular disease. However, it should be appreciated that very many of them with early stage kidney disease, particularly vascular origin, will succumb to cardiovascular and cerebrovascular consequences of vascular disease before they can progress to the most advanced stages of CKD. Early stages of CKD, manifesting as albuminuria and even small reductions in GFR, is now recognized as a major risk factor for heart disease.

A striking interindividual variability in the rate of progression to CKD have a significant heritable component, and a number of genetic loci that contribute to the progression of CKD has been identified. Similarly, it has been noted that women of reproductive age who are relatively protected against the development of many kidney diseases, and sex-specific responses to angiotensin II and blockade have been identified.

Potential risk factors of  CKD incidence

Clinical factors

diabetes
hypertension
autoimmune diseases
systemic infection
Urinary tract infections
Urinary tract stones
Lower urinary tract obstruction
malignancy

Family history of CKD
Recovery from ARF
Decrease in renal mass
Exposed to certain drugs
Low birth weight   

 Factors sosiodemografis

geriatrics
American minority status: African, American, American Indian, Spanish, Asian or Pacific Islands are exposed to some chemical conditions and environmental education / low income

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Related Article:

1. Pathophysiology of Chronic Kidney Disease

2. Symptoms and Signs of Chronic Kidney Disease

3. How to Treat and Therapy of Chronic Kidney Disease