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The kidneys may well be the most misunderstood of all the major organs. Patients often fail to grasp the seriousness of their condition and, without a proper understanding, cannot take appropriate steps to ameliorate their condition. Part of the reason for this is the very nature of kidney disease. Most of the damage of kidney disease has already taken place by the time the patient becomes aware that there is a problem. The "silent killer" is easy to ignore; and by the time some patients are roused into action, it is in a last-ditch effort to avoid dialysis.
When attempting to properly treat kidney disease, patients usually first look to their nephrologists who typically use anti-hypertensive medications as a first line of defense. Only very rarely do they give patients any advice about diet. When patients press for further options they are offered more medications and are told that if they are lucky, eventually they will be transplanted.
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Those patients who venture outside of mainstream medicine in search of other options are confronted with confusing and often contradictory information, much of which is inappropriate to their situation. When there is a vacuum of sound medical advice, the internet often fills in the gaps. The patient at least feels they are doing something and not just passively waiting to go on dialysis. However, some good advice is usually mixed with a lot of bad advice. When cranberry juice and herbal diuretics don't stop the progression of chronic kidney disease, the patient often feels they have run out of options.
Patients who turn to alternative practitioners for advice on treating kidney disease often have high expectations and end up disappointed. The gaps in knowledge of nephrology among holistic doctors becomes apparent, particularly with advanced kidney disease. Without a clear understanding of chronic kidney disease, unfortunately patients and practitioners alike often default to many of the prevailing myths surrounding kidney disease. In this article we will look at some of the common misconceptions around kidney disease and how holistic physicians can better serve their renal patients.
Not Using Proper Terminology
Kidney patients experience a huge gap between their experience with their nephrologist and their holistic practitioners. Not only do they operate from different paradigms, they don't even seem to speak the same language. This leaves the patient confused but also contributes to a sense of mistrust from mainstream medicine. How can another practitioner address the kidney patient's concerns if they misuse common terminology?
Kidney function refers to the kidney's filtration ability and only this. The kidneys have many functions including regulating blood pressure, regulating the pH of the blood and producing erythropoietin, but the term kidney function refers only to the ability of the kidneys to filter out uremic wastes. A patient could have any type of kidney ailment from nephrotic syndrome to polycystic kidney disease to chronic kidney infections, and these conditions are serious, but if the kidney's ability to filter wastes has not been compromised, they have 100% kidney function.
Kidney failure refers only to stage 5 chronic kidney disease. There is no such things as stage 3 or stage 4 kidney failure. There is chronic kidney disease which comes in stages, where the kidneys are gradually deteriorating and losing function. If chronic kidney disease continues to progress, it leads to kidney failure. Kidney failure is the state in which the kidneys have lost the ability to filter uremic wastes to the point where lifesaving measures are necessary. If creatinine is normal or just mildly elevated, the patient is not in kidney failure.
Patients in kidney failure may retain some residual function and produce some urine, but if the filtration rate is not high enough to sustain life, they are in renal failure. Residual function may include a high volume of urine, as the kidneys lose the ability to concentrate urine. But this urine is mostly water as the uremic compounds are not being filtered out and remain in the bloodstream.
Not Understanding How Calculations of Kidney Function Work
The most common measurement of kidney function used is eGFR (estimated glomerular filtration rate). This is often taken as what percentage from out of 100% the kidneys are currently operating. It is also used to grade chronic kidney disease. Stage 5 is an eGFR under 15 and considered not enough activity in the kidney to sustain life. Intervention in the form of dialysis or a transplant will be necessary at this point.
However, one should consider how eGFR is calculated. Four values are plugged into a formula that includes creatinine, age, gender, and race. Creatinine is one uremic waste product that the kidneys need to clear. There are more than 3,000 different uremic waste products that the kidneys handle, but creatinine tends to be the most stable.1 Creatinine is a waste product that comes from muscle tissue and since muscle mass does not shift significantly from one day to the next, creatinine tends to be more reliable than other potential markers. BUN (blood urea nitrogen) is also a uremic waste product, but BUN comes from dietary protein and can shift rapidly based on protein intake.
Age is also a factor in calculating eGFR. Some loss of kidney function is part of the aging process, and age-related kidney decline can lead to kidney failure in an otherwise healthy individual. However, it is important to know that anyone over age 60 will have a low eGFR no matter how healthy they are. This is simply how the formula is designed.2 Many elderly patients have consulted the author in a panic because their eGFR is low. It is important for practitioners to keep this in mind and look to the creatinine level directly to judge the patient's situation.
Since men have a greater muscle mass than women, their creatinine will run higher. This is why gender is factored into the calculation for eGFR. Race is also factored in as those of African descent tend to have a higher baseline creatinine. However, many practitioners encounter the extremely fit young man who has a high creatinine and low eGFR. This is due to the increased muscle mass and may not be indicative of kidney weakness. For these people, it is good to run Cystatin C, an altogether different indicator of kidney function that is not affected by muscle mass.3
Misinterpreting Wide Fluctuations
With healthy kidneys, measuring function is often straightforward: the amount of the waste product creatinine present per volume unit of blood. A creatinine under 1.0 or under 1.3 is a healthy kidney, and whether the patient drank water the day before will have little impact on the creatinine. As the creatinine creeps up above 1.3 toward 2.0 and beyond, small changes in hydration can result in wide readings. Dehydration will cause the creatinine to be more concentrated. While a healthy kidney tightly regulates the water balance, advanced kidney disease often brings large shifts in the numbers. This is not necessarily reflective of an actual shift in the kidney filtration.
It is not always straightforward whether or not the patient is dehydrated and if dehydration is shifting the serum creatinine. Dehydration may be apparent from the specific gravity on the urinalysis or a pH that is more acidic than usual. A high hemoglobin/ hematocrit may also indicate dehydration, but since these numbers tend to be low with chronic kidney disease, it may be difficult to tell.4 It is also important to know if the patient has been warned against drinking too much water due to concerns over cardiac stress with fluid overload.
Underestimating the Relationship Between Filtration and Blood Pressure
Hypertension is easy for many patients to ignore, but once the damage to the kidneys becomes apparent, patients want to get on track. Now they're ready to get serious, take their blood pressure medications and do holistic interventions to keep their blood pressure down. But much to their dismay, their kidney function doesn't get better, it actually gets worse. The patient may interpret this as a side effect of their medication and blame the toxicity of the drug. They stop the blood pressure medication and their kidney function gets better, so in their mind clearly the drugs were the problem. And since their listlessness and fatigue seems worse with an alpha blocker or beta blocker, who can blame them?
Convinced that blood pressure medications are the biggest issue, the patient may want to leave well enough alone and think that out-of-control blood pressure is really not all that bad. Or if they're seeking out alternatives, they believe that If only the blood pressure were managed naturally instead of with medications, it would be different. But much to their dismay, natural agents like Rauwolfia, celery seed, hibiscus, and magnesium don't seem to help the kidney function either.
This is often a difficult situation and it can be hard to convince these patients that blood pressure management is essential. As the kidneys filter the blood across a pressure gradient, the more internal tension there is in the kidney, the better it will filter the blood. It's often useful for the patient to compare this to cleaning with a sponge. The tighter one squeezes a sponge, the better it cleans. When the kidneys are weak and not filtering the blood well, the blood pressure goes up. This helps the kidneys filter out the waste products. A healthy kidney does not need elevated blood pressure to sustain normal filtration. Correcting the blood pressure did not damage the kidneys, it simply revealed how much damage had already taken place. And like a sponge that is squeezed too vigorously and becomes worn out, the extra wear and tear of uncontrolled blood pressure will make the situation worse in the long term, even if it temporarily makes the serum creatinine better.5
Patients coming to alternative practitioners often hope to be able to discontinue their prescription medications. They need to understand that with weak kidneys there will be a need for intervention to manage blood pressure most likely from this point forward.5 At best they may be able to reduce the dosage or switch to some agent with fewer side effects. The worst course of action would be to abruptly stop blood pressure medication, especially since there is the possibility of rebound hypertension making the situation much worse.
It is important for the patient and the practitioner to anticipate that once out-of-control blood pressure is brought under control, there may be a sudden elevation in serum creatinine. Understanding the relationship between blood pressure and kidney filtration is necessary to understand the patient's situation. Once the blood pressure is normalized, then evaluating the serum creatinine will give a better picture of the kidney's filtration.
This is true not only for hypertension but also for hypotension and bradycardia. If an elderly patient exhibits low blood pressure and a slowed heart rate, do not jump to the conclusion that high creatinine means kidney dysfunction. There may simply be not enough pressure for filtration to take place. Normalize the blood pressure and heart rate first, and then see if the creatinine goes back down to an acceptable baseline.
Using Diuretics to Build Kidney Function
A diuretic is a stimulant. It temporarily pushes the kidney to expel more water and nothing more. It does not address the root cause of chronic kidney disease or protect the parenchymal tissue of the kidney from damage. One would not use a stimulant for other chronic conditions. One would not prescribe large doses of coffee for adrenal fatigue, and yet herbal diuretics are used as a panacea for all renal problems.
While anuria and oliguria are a problem in advanced kidney disease, as the kidneys break down and lose the ability to produce urine, herbal diuretics are not a solution. Like flogging a dying horse, demanding that it go faster, diuretics only serve to push an already weakened state. This is often difficult for the patient to accept as they believe that kidney cleanse products they purchased from the health food store are helping and they take the increased urine volume as evidence.
This is not to say that diuretics don't have a place. When water retention is a serious issue, diuretics – either natural or by prescription – can provide relief. Diuretics can also be an important line of defense against persistent hypertension. Just don't expect uva ursi, juniper, or parsley to help the kidneys filter wastes any better. The urine will be in a greater volume, but the kidneys are not any stronger.
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