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Aggressive treatment of high blood lipids is warranted. Low-protein, low-salt diet may result in slower progression of CKD and reduction in proteinuria as well as controlling symptoms of advanced CKD to delay dialysis start. Replacement of erythropoietin and calcitriol, two hormones processed by the kidney, is often necessary in people with advanced disease. Guidelines recommend treatment with parenteral iron prior to treatment with erythropoietin. A target hemoglobin level of 9–12 g/dL is recommended. The normalization of hemoglobin has not been found to be of benefit. It is unclear if androgens help with anemia. Phosphate binders are also used to control the serum phosphate levels, which are usually elevated in advanced chronic kidney disease. Although the evidence for them is limited, phosphodiesterase-5 inhibitors and zinc show potential for helping men with sexual dysfunction.
At stage 5 CKD, renal replacement therapy is usually required, in the form of either dialysis or a transplant.
Generally, angiotensin converting enzyme inhibitors (ACEIs) or angiotensin II receptor antagonists (ARBs) are used, as they have been found to slow the progression. They have also been found to reduce the risk of major cardiovascular events such as myocardial infarction, stroke, heart failure, and death from cardiovascular disease when compared to placebo in individuals with CKD. Furthermore, ACEIs may be superior to ARBs for protection against progression to kidney failure and death from any cause in those with CKD. Aggressive blood pressure lowering decreases peoples risk of death.
Although the use of ACE inhibitors and ARBs represents the current standard of care for people with CKD, people progressively lose kidney function while on these medications, as seen in the IDNT and RENAL studies, which reported a decrease over time in estimated GFR (an accurate measure of CKD progression, as detailed in the K/DOQI guidelines) in people treated by these conventional methods.
Treatment consists of addressing the cause, such as by removing an offending drug. There is no clear evidence that corticosteroids help.
Nutrition therapy consists of adequate fluid intake, which can require several liters of extra fluid.
The myriad causes of intrinsic AKI require specific therapies. For example, intrinsic AKI due to vasculitis or glomerulonephritis may respond to steroid medication, cyclophosphamide, and (in some cases) plasma exchange. Toxin-induced prerenal AKI often responds to discontinuation of the offending agent, such as ACE inhibitors, ARB antagonists, aminoglycosides, penicillins, NSAIDs, or paracetamol.
The use of diuretics such as furosemide, is widespread and sometimes convenient in improving fluid overload. It is not associated with higher mortality (risk of death), nor with any reduced mortality or length of intensive care unit or hospital stay.
The aim of the medical treatment is to slow the progression of chronic kidney disease by reducing blood pressure and albumin levels. The current published guidelines define ideal BP of <130/80 mmHg for patients with hypertensive nephropathy; studies show that anything higher or lower than this can increase cardiovascular risk. According to the African American Study of Kidney Disease (AASK) trial, after an additional 5 years follow-up upon completion of the 10-year trial, up to 65% of the cohort had progressive nephropathy despite having controlled the mean systolic BP level <135 mmHg.
ACE inhibitors, angiotensin receptor blockers, direct renin inhibitors and aldosterone antagonists, are pharmacological treatments that can be used to lower BP to target levels; hence reducing neuropathy and proteinuria progression. The management plan should be individualized based on the condition of the patients including comorbidities and previous medical history.
In addition, there are lifestyle changes that can be made. Weight reduction, exercise, reducing salt intake can be done to manage hypertensive nephropathy.
In prerenal AKI without fluid overload, administration of intravenous fluids is typically the first step to improving kidney function. Volume status may be monitored with the use of a central venous catheter to avoid over- or under-replacement of fluid.
If low blood pressure persists despite providing a person with adequate amounts of intravenous fluid, medications that increase blood pressure (vasopressors) such as norepinephrine and in certain circumstances medications that improve the heart's ability to pump (known as inotropes) such as dobutamine may be given to improve blood flow to the kidney. While a useful vasopressor, there is no evidence to suggest that dopamine is of any specific benefit and may be harmful.
The ideal treatment for IgAN would remove IgA from the glomerulus and prevent further IgA deposition. This goal still remains a remote prospect. There are a few additional caveats that have to be considered while treating IgA nephropathy. IgA nephropathy has a very variable course, ranging from a benign recurrent hematuria up to a rapid progression to chronic kidney failure. Hence the decision on which patients to treat should be based on the prognostic factors and the risk of progression. Also, IgA nephropathy recurs in transplants despite the use of ciclosporin, azathioprine or mycophenolate mofetil and steroids in these patients. There are persisting uncertainties, due to the limited number of patients included in the few controlled randomized studies performed to date, which hardly produce statistically significant evidence regarding the heterogeneity of IgA nephropathy patients, the diversity of study treatment protocols, and the length of follow-up.
Patients with isolated hematuria, proteinuria < 1 g/day and normal renal function have a benign course and are generally just followed up annually. In cases where tonsillitis is the precipitating factor for episodic hematuria, tonsillectomy has been claimed to reduce the frequency of those episodes. However, it does not reduce the incidence of progressive kidney failure. Also, the natural history of the disease is such that episodes of frank hematuria reduce over time, independent of any specific treatment. Similarly, prophylactic antibiotics have not been proven to be beneficial. Dietary gluten restriction, used to reduce mucosal antigen challenge, also has not been shown to preserve kidney function. Phenytoin has also been tried without any benefit.
A subset of IgA nephropathy patients, who have minimal change disease on light microscopy and clinically have nephrotic syndrome, show an exquisite response to steroids, behaving more or less like minimal change disease. In other patients, the evidence for steroids is not compelling. Short courses of high dose steroids have been proven to lack benefit. However, in patients with preserved renal function and proteinuria (1-3.5 g/day), a recent prospective study has shown that 6 months regimen of steroids may lessen proteinuria and preserve renal function. However, the risks of long-term steroid use have to be weighed in such cases. It should be noted that the study had 10 years of patient follow-up data, and did show a benefit for steroid therapy; there was a lower chance of reaching end-stage renal disease (renal function so poor that dialysis was required) in the steroid group. Importantly, angiotensin-converting enzyme inhibitors were used in both groups equally.
Cyclophosphamide had been used in combination with anti-platelet/anticoagulants in unselected IgA nephropathy patients with conflicting results. Also, the side effect profile of this drug, including long term risk of malignancy and sterility, made it an unfavorable choice for use in young adults. However, one recent study, in a carefully selected high risk population of patients with declining GFR, showed that a combination of steroids and cyclophosphamide for the initial 3 months followed by azathioprine for a minimum of 2 years resulted in a significant preservation of renal function. Other agents such as mycophenolate mofetil, ciclosporin and mizoribine have also been tried with varying results.
A study from Mayo Clinic did show that long term treatment with omega-3 fatty acids results in reduction of progression to kidney failure, without, however, reducing proteinuria in a subset of patients with high risk of worsening kidney function. However, these results have not been reproduced by other study groups and in two subsequent meta-analyses. However, fish oil therapy does not have the drawbacks of immunosuppressive therapy. Also, apart from its unpleasant taste and abdominal discomfort, it is relatively safe to consume.
The events that tend to progressive kidney failure are not unique to IgA nephropathy and non-specific measures to reduce the same would be equally useful. These include low-protein diet and optimal control of blood pressure. The choice of the antihypertensive agent is open as long as the blood pressure is controlled to desired level. However, Angiotensin converting enzyme inhibitors and Angiotensin II receptor antagonists are favoured due to their anti-proteinuric effect.
In terms of treatment/management for medullary cystic kidney disease, at present there are no specific therapies for this disease, and there are no specific diets known to slow progression of the disease. However, management for the symptoms can be dealt with as follows: erythropoietin is used to treat anemia, and growth hormone is used when growth becomes an issue. Additionally, a renal transplant may be needed at some point.
Finally, foods that contain potassium and phosphate must be reduced
Treatment of analgesic nephropathy begins with the discontinuation of analgesics, which often halts the progression of the disease and may even result in normalization of kidney function.
There is as yet inadeqaute data from randomised controlled trials.
Treatment with HAART and ACE inhibitors/Angiotensin receptor blockers has been shown to be beneficial and should be given to all patients unless otherwise contra-indicated. General renoprotective measures and the treatment of the complications of nephrotic syndrome and kidney failure are adjunctive.
Corticosteroid treatment can be useful in patients who do not respond to the above treatment. There is some evidence that ciclosporin might be helpful in selective cases, however further trials are required on both steroids and ciclosporin before these drugs can become standardised treatment if at all.
Adenosine antagonists such as the methylxanthines theophylline and aminophylline, may help although studies have conflicting results.
Evidence supports the use of N-acetylcysteine with intravenous saline among those getting low molecular weight contrast. The use of statins with N-acetylcysteine and intravenous saline is also supported.
Often, aggressive treatment is unnecessary for people with MSK disease that does not cause any symptoms (asymptomatic). In such cases, treatment may consist of maintaining adequate fluid intake, with the goal of decreasing the risk of developing kidney stones (nephrolithiasis). Cases of recurrent kidney stone formation may warrant evaluation for possible underlying metabolic abnormalities.
In patients with low levels of citrate in the urine (hypocitraturia) and incomplete distal renal tubular acidosis, treatment with potassium citrate helps prevent the formation of new kidney stones. Urinary tract infections, when they occur, should also be treated.
Patients with the more rare form of MSK marked by chronic pain typically require pain management. Non-obstructing stones in MSK can be associated with significant and chronic pain even if they're not passing. The pain in this situation can be constant. It is not certain what causes this pain but researchers have proposed that the small numerous stones seen in MSK may cause obstruction of the small tubules and collecting ducts in the kidney which could lead to the pain. This pain can often be debilitating and treatment is challenging. Narcotic medication even with large quantities is sometimes not adequate. Some success with pain control has been reported using laser lithotripsy (called “ureteroscopic laser papillotomy”).
The optimal treatment is prevention. Rigorous and continuous control of phosphate and calcium balance most probably will avoid the metabolic changes which may lead to calciphylaxis.
There is no specific treatment. Of the treatments that exist, none are internationally recognized as the standard of care. An acceptable treatment could include:
- Dialysis (the number of sessions may be increased)
- Intensive wound care
- Clot-dissolving agents (tissue plasminogen activator)
- Hyperbaric oxygen
- Maggot larval debridement
- Adequate pain control
- Correction of the underlying plasma calcium and phosphorus abnormalities (lowering the Ca x P product below 55 mg2/dL2)
- Sodium thiosulfate
- Avoiding (further) local tissue trauma (including avoiding all subcutaneous injections, and all not-absolutely-necessary infusions and transfusions)
- Urgent parathyroidectomy: The efficacy of this measure remains uncertain although calciphylaxis is associated with frank hyperparathyroidism. Urgent parathyroidectomy may benefit those patients who have uncontrollable plasma calcium and phosphorus concentrations despite dialysis. Also, cinacalcet can be used and may serve as an alternative to parathyroidectomy.
- Patients who receive kidney transplants also receive immunosuppression. Considering lowering the dose of or discontinuing the use of immunosuppressive drugs in people who have received kidney transplants and continue to have persistent or progressive calciphylactic skin lesions can contribute to an acceptable treatment of calciphylaxis.
- A group has reported plasma exchange effective and propose a serum marker and perhaps mediator (calciprotein particles)
People who received earlier referrals to a nephrology specialist, meaning a longer time before they had to start dialysis, had a shorter initial hospitalization and reduced risk of death after the start of dialysis. The authors highlighted the resulting importance of early referral in slowing progression of chronic kidney disease. Other methods of reducing disease progression include minimizing exposure to nephrotoxins such as NSAIDS and intravenous contrast.
In non-diabetics and people with type 1 diabetes, a low protein diet is found to have a preventative effect on progression of chronic kidney disease. However, this effect does not apply to people with type 2 diabetes. A whole food, plant-based diet may help some people with kidney disease. A high protein diet from either animal or plant sources appears to have negative effects on kidney function at least in the short term.
The kidneys are the only body system that are directly affected by tubulointerstitial nephritis. Kidney function is usually reduced; the kidneys can be just slightly dysfunctional, or fail completely.
In chronic tubulointerstitial nephritis, the most serious long-term effect is kidney failure. When the proximal tubule is injured, sodium, potassium, bicarbonate, uric acid, and phosphate reabsorption may be reduced or changed, resulting in low bicarbonate, known as metabolic acidosis, low potassium, low uric acid known as hypouricemia, and low phosphate known as hypophosphatemia. Damage to the distal tubule may cause loss of urine-concentrating ability and polyuria.
In most cases of acute tubulointerstitial nephritis, the function of the kidneys will return after the harmful drug is not taken anymore, or when the underlying disease is cured by treatment. If the illness is caused by an allergic reaction, a corticosteroid may speed the recovery kidney function; however, this is often not the case.
Chronic tubulointerstitial nephritis has no cure. Some patients may require dialysis. Eventually, a kidney transplant may be needed.
Unfortunately, response to treatment is not guaranteed. Also, the necrotic skin areas may get infected, and this then may lead to sepsis (i.e. infection of blood with bacteria; sepsis can be life-threatening) in some patients. Overall, the clinical prognosis remains poor.
Initial treatment is with adequate hydration, alkalization of the urine with citrate supplementation or acetazolamide, and dietary modification to reduce salt and protein intake (especially methionine). If this fails then patients are usually started on chelation therapy with an agent such as penicillamine. Tiopronin is another agent.
Once renal stones have formed, however, the first-line treatment is ESWL (Extracorporeal shock wave lithotripsy). If ESWL do not work efficiently surgery can be necessary. Both endoscopic surgery and conventional open-abdominal surgery have proven to be effective treatment modalities for patients with more advanced disease. Adequate hydration is the foremost aim of treatment to prevent cysteine stones. The goal is to increase the urine volume because the concentration of cystine in the urine is reduced which prevents cystine from precipitating from the urine and forming stones. People with cystine stones should consume 5 to 7 liters a day. The rationale behind alkalizing the urine is that cystine tends to stay in solution and causes no harm. In order to alkalize the urine, sodium biocarbonate has been used. One must be careful in alkalizing their urine because it could lead to other forms of stones in process of preventing cystine stones. Penicillamine is a drug that acts to form a complex with cystine that is 50 times more soluble than cystine itself. Percutaneous nephrolithotripsy (PNL) is performed via a port created by puncturing the kidney through the skin and enlarging the access port to 1 cm in diameter. Most of the time, cystine stones are too dense to be broken up by shock (ESWL) so PNL is needed.
Videos of surgery are available on various websites that show stone removal by percutaneous nephrolithotomy.
In February 2017, an article was published in Nature Medicine entitled 'Alpha lipoic acid treatment prevents cystine urolithiasis in a mouse model of cystinuria', suggesting that a high dose of the readily available antioxidant, alpha-lipoic acid at 2,700 mg/67 kg body weight daily reduced the incidence of stones. The effects were dose dependent. The results are unprecedented for cystinuria. A clinical trial is underway based on this mouse model.
The long-term use of lithium, a medication commonly used to treat bipolar disorder and schizoaffective disorders, is known to cause nephropathy.
Nephropathy can be associated with some therapies used to treat cancer. The most common form of kidney disease in cancer patients is Acute Kidney Injury (AKI) which can usually be due to volume depletion from vomiting and diarrhea that occur following chemotherapy or occasionally due to kidney toxicities of chemotherapeutic agents. Kidney failure from break down of cancer cells, usually after chemotherapy, is unique to onconephrology. Several chemotherapeutic agents, for example Cisplatin, are associated with acute and chronic kidney injuries. Newer agents such as anti Vascular Endothelial Growth Factor (anti VEGF) are also associated with similar injuries, as well as proteinuria, hypertension and thrombotic microangiopathy.
As of today, no agreed-upon treatment of Dent's disease is known and no therapy has been formally accepted. Most treatment measures are supportive in nature:
- Thiazide diuretics (i.e. hydrochlorothiazide) have been used with success in reducing the calcium output in urine, but they are also known to cause hypokalemia.
- In rats with diabetes insipidus, thiazide diuretics inhibit the NaCl cotransporter in the renal distal convoluted tubule, leading indirectly to less water and solutes being delivered to the distal tubule. The impairment of Na transport in the distal convoluted tubule induces natriuresis and water loss, while increasing the reabsorption of calcium in this segment in a manner unrelated to sodium transport.
- Amiloride also increases distal tubular calcium reabsorption and has been used as a therapy for idiopathic hypercalciuria.
- A combination of 25 mg of chlorthalidone plus 5 mg of amiloride daily led to a substantial reduction in urine calcium in Dent's patients, but urine pH was "significantly higher in patients with Dent’s disease than in those with idiopathic hypercalciuria (P < 0.03), and supersaturation for uric acid was consequently lower (P < 0.03)."
- For patients with osteomalacia, vitamin D or derivatives have been employed, apparently with success.
- Some lab tests on mice with CLC-5-related tubular damage showed a high-citrate diet preserved kidney function and delayed progress of kidney disease.
Medical management of patients with CRS is often challenging as focus on treatment of one organ may have worsening outcome on the other. It is known that many of the medications used to treat HF may worsen kidney function. In addition, many trials on HF excluded patients with advanced kidney dysfunction. Therefore, our understanding of CRS management is still limited to this date.
Diuretics
ACEI, ARB, renin inhibitors, aldosterone inhibitors
Natriuretic peptides
Vasopressin antagonists
Adenosine antagonists
Ultrafiltration
Inotropes
Drug regimens prescribed for lupus nephritis include mycophenolate mofetil (MMF), intravenous cyclophosphamide with corticosteroids, and the immune suppressant azathioprine with corticosteroids. MMF and cyclophosphamide with corticosteroids are equally effective in achieving remission of the disease. MMF is safer than cyclophosphamide with corticosteroids, with less chance of causing ovarian failure, immune problems or hair loss. It also works better than azathioprine with corticosteroids for maintenance therapy. Individuals with lupus nephritis have a high risk for B-cell lymphoma (which begins in the immune system cells).
The term "analgesic nephropathy" usually refers to damage induced by excessive use of combinations of these medications, specifically combinations that include phenacetin. For this reason, it is also called analgesic abuse nephropathy. Murray prefers the less judgmental analgesic-associated nephropathy. Both terms are abbreviated to the acronym AAN, by which the condition is also commonly known.