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.

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.

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 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.

Treatment is focused on preventing deposition of uric acid within the urinary system by increasing urine volume with potent diuretics such as furosemide. Raising the urinary pH to a level higher than 7 (alkalinization) is often difficult to attain, although sodium bicarbonate and/or acetazolamide are sometimes used in an attempt to increase uric acid solubility.

Dialysis (preferably hemodialysis) is started if the above measures fail.

Many major studies showing improvement in kidney function in patients with hepatorenal syndrome have involved expansion of the volume of the plasma with albumin given intravenously. The quantity of albumin administered intravenously varies: one cited regimen is 1 gram of albumin per kilogram of body weight intravenously on the first day, followed by 20 to 40 grams daily. Notably, studies have shown that treatment with albumin alone is inferior to treatment with other medications in conjunction with albumin; most studies evaluating pre-transplant therapies for HRS involve the use of albumin in conjunction with other medical or procedural treatment.

Midodrine is an alpha-agonist and octreotide is an analogue of somatostatin, a hormone involved in regulation of blood vessel tone in the gastrointestinal tract. The medications are respectively systemic vasoconstrictors and inhibitors of splanchnic vasodilation, and were not found to be useful when used individually in treatment of hepatorenal syndrome. However, one study of 13 patients with hepatorenal syndrome showed significant improvement in kidney function when the two were used together (with midodrine given orally, octreotide given subcutaneously and both dosed according to blood pressure), with three patients surviving to discharge. Another nonrandomized, observational study of individuals with HRS treated with subcutaneous octreotide and oral midodrine showed that there was increased survival at 30 days.

The vasopressin analogue ornipressin was found in a number of studies to be useful in improvement of kidney function in patients with hepatorenal syndrome, but has been limited in its use, as it can cause severe ischemia to major organs. Terlipressin is a vasopressin analogue that has been found in one large study to be useful for improving kidney function in patients with hepatorenal syndrome with a lesser incidence of ischemia but is not available in the United States. A key criticism of all of these medical therapies has been heterogeneity in the populations investigated and the use of kidney function, instead of mortality, as an outcome measure.

Other agents that have been investigated for use in treatment of HRS include pentoxifylline, acetylcysteine, and misoprostol. The evidence for all of these therapies is based on either case series, or in the case of pentoxifylline, extrapolated from a subset of patients treated for alcoholic hepatitis.

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.

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 definitive treatment for hepatorenal syndrome is liver transplantation, and all other therapies can best be described as bridges to transplantation. While liver transplantation is by far the best available management option for HRS, the mortality of individuals with HRS has been shown to be as high as 25% within the first month after transplantation. Individuals with HRS and evidence of greater hepatic dysfunction (quantified as MELD scores above 36) have been found to be at greatest risk of early mortality after liver transplantation. A further deterioration of kidney function even after liver transplantation in individuals with HRS has been demonstrated in several studies; however, this is transient and thought to be due to the use of medications with toxicity to the kidneys, and specifically the introduction of immunosuppressants such as tacrolimus and cyclosporine that are known to worsen kidney function. Over the long-term, however, individuals with HRS who are the recipients of liver transplants almost universally recover kidney function, and studies show that their survival rates at three years are similar to those who have received liver transplants for reasons other than HRS.

In anticipation of liver transplantation (which may be associated with considerable in-hospital delay), several other strategies have been found to be beneficial in preserving kidney function. These include the use of intravenous albumin infusion, medications (for which the best evidence is for analogues of vasopressin, which causes splanchnic vasoconstriction), radiological shunts to decrease pressure in the portal vein, dialysis, and a specialized albumin-bound membrane dialysis system termed molecular adsorbents recirculation system (MARS) or liver dialysis.

Prompt treatment of some causes of azotemia can result in restoration of kidney function; delayed treatment may result in permanent loss of renal function. Treatment may include hemodialysis or peritoneal dialysis, medications to increase cardiac output and increase blood pressure, and the treatment of the condition that caused the azotemia.

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.

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.

Treatment is dependent on the underlying cause of this symptom. The most easily treatable cause is obstruction of urine flow, which is often solved by insertion of a urinary catheter into the urinary bladder.

Mannitol is a medicine that is used to increase the amount of water removed from the blood and thus improve the blood flow to the kidneys. However, mannitol is contraindicated in anuria secondary to renal disease, severe dehydration, intracranial bleeding (except during craniotomy), severe pulmonary congestion, or pulmonary edema.

Dextrose and Dobutamine are both used to increase blood flow to the kidney and act within 30 to 60 minutes.

The main goal of treatment is to treat shock and preserve kidney function. Initially this is done through the administration of generous amounts of intravenous fluids, usually isotonic saline (0.9% weight per volume sodium chloride solution). In victims of crush syndrome, it is recommended to administer intravenous fluids even before they are extracted from collapsed structures. This will ensure sufficient circulating volume to deal with the muscle cell swelling (which typically commences when blood supply is restored), and to prevent the deposition of myoglobin in the kidneys. Amounts of 6 to 12 liters over 24 hours are recommended. The rate of fluid administration may be altered to achieve a high urine output (200–300 ml/h in adults), unless there are other reasons why this might lead to complications, such as a history of heart failure.

While many sources recommend additional intravenous agents to reduce damage to the kidney, most of the evidence supporting this practice comes from animal studies, and is inconsistent and conflicting. Mannitol acts by osmosis to enhance urine production and is thought to prevent myoglobin deposition in the kidney, but its efficacy has not been shown in studies and there is a risk of worsening kidney function. The addition of bicarbonate to the intravenous fluids may alleviate acidosis (high acid level of the blood) and make the urine more alkaline to prevent cast formation in the kidneys; evidence suggesting that bicarbonate has benefits above saline alone is limited, and it can worsen hypocalcemia by enhancing calcium and phosphate deposition in the tissues. If urine alkalinization is used, the pH of the urine is kept at 6.5 or above. Furosemide, a loop diuretic, is often used to ensure sufficient urine production, but evidence that this prevents kidney failure is lacking.

In the initial stages, electrolyte levels are often abnormal and require correction. High potassium levels can be life-threatening, and respond to increased urine production and renal replacement therapy (see below). Temporary measures include the administration of calcium to protect against cardiac complications, insulin or salbutamol to redistribute potassium into cells, and infusions of bicarbonate solution.

Calcium levels initially tend to be low, but as the situation improves calcium is released from where it has precipitated with phosphate, and vitamin D production resumes, leading to hypercalcemia (abnormally high calcium levels). This "overshoot" occurs in 20–30% of those people who have developed kidney failure.

Management of hematuria is aimed at treating secondary causes of hematuria. If hematuria is a result of a UTI, treatment with antibiotics is usually initiated and urine testing repeated after 6 weeks. If hematuria is secondary to a kidney stone, then management depends on the size of the kidney stone. If the stone is small enough, usually less than 1 cm, then conservative management with analgesics and fluid hydration may be sufficient, however stones that are too bid may require removal by a urologist. Another common cause of hematuria is benign enlargement of the prostate (BPH), treatment is aimed at reducing the size of the bladder with medications like finasteride and symptomatic management with drugs like terazonsin or tamsulosin.

For people with exercise induced hematuria, management is conservative and involves cessation of strenuous activities and keeping hydrated. If the cause of hematuria is a result of malignancy, treatment and management depends on the type and stage of cancer and can involve chemotherapy, radiation or surgical resection of the tumor or organ involved.

Increasing fluid intake to yield a urine output of greater than 2 liters a day can be advantageous for all patients with nephrocalcinosis. Patients with hypercalciuria can reduce calcium excretion by restricting animal protein, limiting sodium intake to less than 100 meq a day and being lax of potassium intake. If changing ones diet alone does not result in an suitable reduction of hypercalciuria, a thiazide diuretic can be administered in patients who do not have hypercalcemia. Citrate can increase the solubility of calcium in urine and limit the development of nephrocalcinosis. Citrate is not given to patients who have urine pH equal to or greater than 7.

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

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 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.

Patients will require dialysis to compensate for the function of their kidneys.

Increase the water intake to prevent oxalates to precipitate .

Minimize dietary intake of oxalates by restricting the intake of leafy vegetables , sesame seeds , tea , cocoa , beet root , spinach , rhubarb , etc.