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Currently, the only clinical/pharmacological treatment available for ADPKD consists in reducing the speed in gain of total kidney volume (TKV) with aquaretics (i.e. tolvaptan), which can alleviate pain while giving the patients a better quality of life for over a mean of 3 years. After this period, patients can restart gaining TKV at pre-treatment rates and may eventually have to go through dialysis and kidney transplant. Paliative treatment modalities involve symptomatic medications (non-opioid and opioid analgesics) for abdominal/retroperitoneal pain. Before the advent of aquaretic medication, the only option for analgesic-resistant pain were simple or complex surgical procedures (i.e. renal cyst aspiration, cyst decortication, renal denervation and nephrectomy), which can result in complications inherent to surgery.
In 2014, Japan was the first country in the world to approve a pharmacological treatment for ADPKD followed by Canada and Europe, which approved the drug tolvaptan for ADPKD patients in the beginning of 2015. Tolvaptan, an aquaretic drug, is a vasopressin receptor 2 (V2) antagonist. Pre-clinical studies had suggested that the molecule cAMP could be involved in the enlargement of ADPKD cysts, and studies on rodents confirmed the role of vasopressin in increasing the levels of cAMP in the kidney, which laid the basis for the conduction of clinical studies. Because data from the Consortium for Radiologic Imaging Studies of Polycystic Kidney Disease (CRISP) led by Mayo Clinic showed that total kidney volume (TKV) predicted the risk of developing renal insufficiency in patients with ADPKD, the TEMPO 3:4 trial, which enrolled patients from 129 sites worldwide from 2007 to 2009, evaluated TKV as a primary end-point to test the efficacy of tolvaptan in ADPKD patients. That study showed a significant decrease in the ratio of TKV increase and deterring of renal function decline in ADPKD patients after treatment with tolvaptan; however, because laboratory test results regarding liver function appeared elevated in a percentage of patients enrolled in that study, the approval of the drug was either delayed by regulatory agencies or, as in case of the US, altogether denied.
The treatment options for autosomal recessive polycystic kidney disease, given there is no current cure, are:
- Medications for hypertension
- Medications and/or surgery for pain
- Antibiotics for infection
- Kidney transplantation(in serious cases)
- Dialysis (if renal failure)
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
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.
There is no FDA-approved treatment. However, it has been shown that mild to moderate dietary restrictions slow the progression of autosomal dominant polycystic kidney disease (ADPKD).
If and when the disease progresses enough in a given case, the nephrologist or other practitioner and the patient will have to decide what form of renal replacement therapy will be used to treat end-stage kidney disease (kidney failure, typically stage 4 or 5 of chronic kidney disease).
That will either be some form of dialysis, which can be done at least two different ways at varying frequencies and durations (whether it is done at home or in the clinic depends on the method used and the patient's stability and training) and eventually, if they are eligible because of the nature and severity of their condition and if a suitable match can be found, unilateral or bilateral kidney transplantation.
A Cochrane Review study of autosomal dominant polycystic kidney disease made note of the fact that it is important at all times, while avoiding antibiotic resistance, to control infections of the cysts in the kidneys, and if affected, the liver, when needed for a certain duration to combat infection, by using, quote: "bacteriostatic and bacteriocidal drugs".
The management of this condition can be done via-improvement of any electrolyte imbalance, as well as, hypertension and anemia treatment as the individuals condition warrants.
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 treatment of kidney damage may reverse or delay the progression of the disease. Kidney damage is treated by prescribing drugs:
- Corticosteroids: the result is a decrease in the proteinuria and the risk of infection as well as a resolution of the edema. Prednisone is usually prescribed at a dose of 60 mg/m² of body surface area/day in a first treatment for 4–8 weeks. After this period the dose is reduced to 40 mg/m² for a further 4 weeks. Patients suffering a relapse or children are treated with prednisolone 2 mg/kg/day till urine becomes negative for protein. Then, 1.5 mg/kg/day for 4 weeks. Frequent relapses treated by: cyclophosphamide or nitrogen mustard or cyclosporin or levamisole. Patients can respond to prednisone in a number of different ways:
- Corticosteroid sensitive patient or early steroid-responder: the subject responds to the corticosteroids in the first 8 weeks of treatment. This is demonstrated by a strong diuresis and the disappearance of edemas, and also by a negative test for proteinuria in three urine samples taken during the night.
- Corticosteroid resistant patient or late steroid-responder: the proteinuria persists after the 8-week treatment. The lack of response is indicative of the seriousness of the glomerular damage, which could develop into chronic kidney failure.
- Corticosteroid tolerant patient: complications such as hypertension appear, patients gain a lot of weight and can develop aseptic or avascular necrosis of the hip or knee, cataracts and thrombotic phenomena and/or embolisms.
- Corticosteroid dependent patient: proteinuria appears when the dose of corticosteroid is decreased or there is a relapse in the first two weeks after treatment is completed.
The susceptibility testing in vitro to glucocorticoids on patient's peripheral blood mononuclear cells is associated with the incidence of not optimal clinical responses: the most sensitive patients in vitro have shown a higher incidence of corticodependence, while the most resistant patients in vitro showed a higher incidence of ineffective therapy.
- Immunosupressors (cyclophosphamide): only indicated in recurring nephrotic syndrome in corticosteroid dependent or intolerant patients. In the first two cases the proteinuria has to be negated before treatment with the immunosuppressor can begin, which involves a prolonged treatment with prednisone. The negation of the proteinuria indicates the exact moment when treatment with cyclophosphamide can begin. The treatment is continued for 8 weeks at a dose of 3 mg/kg/day, the immunosuppression is halted after this period. In order to be able to start this treatment the patient should not be suffering from neutropenia nor anaemia, which would cause further complications. A possible side effect of the cyclophosphamide is alopecia. Complete blood count tests are carried out during the treatment in order to give advance warning of a possible infection.
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.
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.
There is no proven therapy for the CFHR5 nephropathy, although research is currently underway to develop ways of preventing kidney failure developing in those affected.
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.
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.
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.
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.
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.
The objective of this treatment is to treat the imbalances brought about by the illness: edema, hypoalbuminemia, hyperlipemia, hypercoagulability and infectious complications.
- Edema: a return to an unswollen state is the prime objective of this treatment of nephrotic syndrome. It is carried out through the combination of a number of recommendations:
- Rest: depending on the seriousness of the edema and taking into account the risk of thrombosis caused by prolonged bed rest.
- Medical nutrition therapy: based on a diet with the correct energy intake and balance of proteins that will be used in synthesis processes and not as a source of calories. A total of 35 kcal/kg body weight/day is normally recommended. This diet should also comply with two more requirements: the first is to not consume more than 1 g of protein/kg body weight/ day, as a greater amount could increase the degree of proteinuria and cause a negative nitrogen balance. Patients are usually recommended lean cuts of meat, fish, and poultry. The second guideline requires that the amount of water ingested is not greater than the level of diuresis. In order to facilitate this the consumption of salt must also be controlled, as this contributes to water retention. It is advisable to restrict the ingestion of sodium to 1 or 2 g/day, which means that salt cannot be used in cooking and salty foods should also be avoided. Foods high in sodium include seasoning blends (garlic salt, Adobo, season salt, etc.) canned soups, canned vegetables containing salt, luncheon meats including turkey, ham, bologna, and salami, prepared foods, fast foods, soy sauce, ketchup, and salad dressings. On food labels, compare milligrams of sodium to calories per serving. Sodium should be less than or equal to calories per serving.
- Medication: The pharmacological treatment of edema is based on the prescription of diuretic drugs (especially loop diuretics, such as furosemide). In severe cases of edema (or in cases with physiological repercussions, such as scrotal, preputial or urethral edema) or in patients with one of a number of severe infections (such as sepsis or pleural effusion), the diuretics can be administered intravenously. This occurs where the risk from plasmatic expansion is considered greater than the risk of severe hypovolemia, which can be caused by the strong diuretic action of intravenous treatment. The procedure is the following:
- Hypoalbuminemia: is treated using the medical nutrition therapy described as a treatment for edema. It includes a moderate intake of foods rich in animal proteins.
- Hyperlipidaemia: depending of the seriousness of the condition it can be treated with medical nutrition therapy as the only treatment or combined with drug therapy. The ingestion of cholesterol should be less than 300 mg/day, which will require a switch to foods that are low in saturated fats. Avoid saturated fats such as butter, cheese, fried foods, fatty cuts of red meat, egg yolks, and poultry skin. Increase unsaturated fat intake, including olive oil, canola oil, peanut butter, avocadoes, fish and nuts. In cases of severe hyperlipidaemia that are unresponsive to nutrition therapy the use of hypolipidemic drugs, may be necessary (these include statins, fibrates and resinous sequesters of bile acids).
- Thrombophilia: low molecular weight heparin (LMWH) may be appropriate for use as a prophylactic in some circumstances, such as in asymptomatic patients that have no history of suffering from thromboembolism. When the thrombophilia is such that it leads to the formation of blood clots, heparin is given for at least 5 days along with oral anticoagulants (OAC). During this time and if the prothrombin time is within its therapeutic range (between 2 and 3), it may be possible to suspend the LMWH while maintaining the OACs for at least 6 months.
- Infectious complications: an appropriate course of antibacterial drugs can be taken according to the infectious agent.
In addition to these key imbalances, vitamin D and calcium are also taken orally in case the alteration of vitamin D causes a severe hypocalcaemia, this treatment has the goal of restoring physiological levels of calcium in the patient.
- Achieving better blood glucose level control if the patient is diabetic.
- Blood pressure control. ACE inhibitors are the drug of choice. Independent of their blood pressure lowering effect, they have been shown to decrease protein loss.
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)
Most patients with thin basement membrane disease need only reassurance. Indeed, this disease was previously referred to as "benign familial hematuria" because of its usually benign course. Angiotensin converting enzyme inhibitors have been suggested to reduce the episodes of hematuria, though controlled studies are lacking. Treating co-existing hypercalciuria and hyperuricosuria will also be helpful in reducing hematuria.
The molecular basis for thin basement membrane disease has yet to be elucidated fully; however, defects in the gene encoding the a4 chain of type IV collagen have been reported in some families.
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.
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.
Adenosine antagonists such as the methylxanthines theophylline and aminophylline, may help although studies have conflicting results.
There is no standard treatment for LCDD. High-dose melphalan in conjunction with autologous stem cell transplantation has been used in some patients. A regimen of bortezomib and dexamethasone has also been examined.