Role of Acetazolamide and Hydrochlorothiazide Followed by Furosemide in Treating Nephrotic Edema

Acetazolamide and Hydrochlorothiazide Followed by Furosemide Versus Hydrochlorothiazide and Furosemide Followed by Furosemide for the Treatment of Adults With Refractory Nephrotic Edema: A Randomized, Double-Blind Trial

The purpose of this study is to determine whether using furosemide following acetazolamide is effective in treating refractory edema associated with nephrotic syndrome.

Edema is referred to increase in interstitial fluid that is clinically evident. The main causes of generalized edema are heart failure, renal failure, nephrotic syndrome, glomerulonephritis and chronic liver failure. In some cases, edema is treated by management of the underlying disease. However, in some other cases edema may persist and become more severe that needs adjuvant treatments. Because use of diuretics such as furosemide and hydrochlorothiazide is not completely effective in treating severe refractory edema, use of some other diuretics is also recommended. In this double-blind clinical trial, weight and some lab data including blood urea nitrogen, serum creatinine, serum sodium, serum potassium, serum albumin, urine sodium, urine potassium, 24-hour urine volume, 24-hour urine protein and 24-hour urine creatinine of 20 random adult patients with nephrotic syndrome who have refractory edema and GFR>60 ml/min/1.73m2 and are referred to nephrology clinic of Shiraz University of Medical Sciences will be measured; the patients should not have hypokalemia and other causes of edema such as heart failure or cirrhosis. Then the patients are divided into 2 groups with 10 members in each. The first group will be prescribed 40 mg of furosemide and 50 mg of hydrochlorothiazide and the second one will receive 250 mg of acetazolamide and 50 mg of hydrochlorothiazide daily for 1 week. Then, weight and mentioned lab data will be measured again. After that, all the patients will have 40 mg of furosemide daily for 2 weeks. Then, weight and mentioned lab data will be measured for one more time.

Inclusion Criteria:

1. Having refractory edema due to nephrotic syndrome
2. Having GFR>60 ml/min/1.73m2
3. Being able to come for weekly visit
4. Having the minimum age of 18 years
5. Signing the informed consent form

Exclusion Criteria:

1. Hypokalemia
2. Pregnancy
3. Renal transplant
4. active malignancy or infection
5. acidosis
6. Using NSAIDs
7. Having another causes of edema including liver cirrhosis, heart failure
8. Neurologic or psychiatric problem hindering adherence to the study protocol