Chronic Kidney Disease is a misunderstood clinical entity, whose importance has only emerged in recent years and whose great clinical value has not been properly recognized by the community of medical specialists involved in managing renal patients. Characteristic is the case of a patient to whom the doctor announces that he suffers from high cholesterol while the creatinine levels are marginally elevated, with interest concentrating exclusively on how cholesterol can be reduced, how long it will take, which is the best diet, when should the patient start treatment, how often one should be tested and the side effects of the medication etc. As for creatinine, it is considered enough for the patient to increase the daily water intake and the problem may be solved without any other intervention! So, let's look at some myths circulating around Chronic Kidney Disease and which often inhibit the treatment of the disease.

"First myth: if you drink some more water your creatinine levels will fall." This is the most common myth among renal patients. It is a fact that an elevated creatinine value may be a transient finding in the context of some conditions that are not related to the kidney (e.g. antibiotic treatment or other drugs, nutritional factors, muscle mass, etc.), but on the other hand, this elevated value may be suggesting some degree of renal impairment, especially in high-risk patients for renal disease (e.g. diabetic, hypertensive, obese, etc.). In such cases, the physician's purpose is to carefully investigate the causes of creatinine elevation and to further examine the patient for potential renal damage, not just to frivolously advise additional daily water intake, which, obviously in no way heals the damage! There are even cases in which excessive water consumption can lead to the worsening of a kidney problem, as is the case for people with a solitary kidney (congenital or of acquired etiology). In such cases, consumption of additional water may further harm the patient, leading to ultrafiltration and hyperfunction of the kidney with damaging results (e.g., exacerbation of existing proteinuria). Increased water consumption (> 2 L) is recommended in very specific cases, such as for patients with recurrent nephrolithiasis or recurrent urinary tract infections and for elderly patients taking diuretics. Even in the latter case, because of the thirst mechanism, it is imperative that patients are closely monitored so that their daily intake of water is within recommended limits and diuretic action does not lead to dehydration.

"Second myth: your creatinine levels are within the normal range, so there is no problem with your kidneys." What is normal or not when assessing laboratory parameter is in no way dependent only on the normal limits given by each laboratory. What is of particular value is the comparative study of the laboratory parameters over time as well as the consideration of the particular characteristics of the person under consideration. For example, a creatinine value of 1.3 mg / dl may be a perfectly normal value for a 40-year-old muscular man whereas the same value for a 70-year-old man may suggest a loss of renal function of up to 60-70%! Also, a creatinine value that ranged from 0.6 to 0.8 mg / dl years ago and is currently estimated at 1.2 and 1.3 mg / dl is an important pathological finding, which should be evaluated with due care, even if these values remain within the normal limits given by the laboratory. Finally, it is noted that the value of creatinine is only one of many indicators of kidney damage. There are a few cases where even though creatinine is considered within normal limits, the kidney has a significant degree of damage. It is therefore necessary to further evaluate several different indicators when diagnosing a patient's kidney health status.

"Third myth: Increased creatinine is not important. More important is your increased cholesterol value". Renal disease is considered by many specialists to be equivalent to coronary heart disease. This means that a patient with impaired renal function and a patient with a history of myocardial infarction undertake theoretically the same risk of having a cardiovascular event in the future. This fact, combined with the empirical observation that chronic renal disease significantly increases the risk of cardiovascular disease (coronary artery disease, stroke, peripheral arterial disease, etc.) or even the risk of death of a patient, constitute proof that the elevated creatinine level is a serious disease indicator that needs to be assessed with due care and which is clearly more severe than an elevated cholesterol value, being after all just one of many risk factors to the onset of cardiovascular disease.

"Fourth myth: Chronic kidney disease is only dangerous at its last stages, just before the patient begins dialysis treatments." It is a fact that chronic renal disease is an asymptomatic disease which in its final stages is accompanied by a remarkable symptomatology. However, its timely diagnosis is important for three reasons. Firstly, because of the previously mentioned increase in cardiovascular risk. Secondly, due to the significant therapeutic interventions that can be made in the early stages of the disease, either to induce cure (less often), or to slow down the progression of renal damage. And thirdly, because of the "silent" complications of the disease that start to appear during its third stage. These complications include among others, anemia of renal disease and bone renal disease, which if diagnosed relatively early, can be treated with the appropriate medication.

The demolition of these myths is imperative in adequately treating patients with CKD, thus substantially improving their level of health. Due to the high incidence of the disease both in the general population and in specific patient samples (diabetics, hypertensives etc.), the participation of the nephrologist in the patients’ medical team is mandatory. It is also important that other medical specialists involved in treating CKD patients are well educated as to the nature and peculiarities of renal disease. In the end, we can all agree that an increased creatinine value means much more than a simple recommendation of drinking a few more glasses of water daily. To paraphrase the old English proverb: “A glass of water a day cannot keep the nephrologist away”.

Anastasios Ch. Fountoglou, Specialist Nephrologist, Nephroxenia Dialysis Center Corfu

Bibliography

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