Hematuria sulfonamides

Sulfonamides may precipitate in urine, especially at neutral or acid pH, producing crystalluria, hematuria, or even obstruction. This is rarely a problem with the more soluble sulfonamides (eg, sulfisoxazole). Sulfadiazine when given in large doses, particularly if fluid intake is poor, can cause crystalluria. Crystalluria is treated by administration of sodium bicarbonate to alkalinize the urine and fluids to maintain adequate hydration. Sulfonamides have also been implicated in various types of nephrosis and in allergic nephritis. 

Adverse effects The side effects include gastrointestinal distress. At higher doses, albuminuria, hematuria and rashes may develop. Methenamine mandelate is contraindicated in treating patients with renal insufficiency, because mandelic acid may precipitate. Sulfonamides react with formaldehyde and must not be used concomitantly with methenamine. 

Nissen Nl, Aagaard K, Flindt-Flansen E. Sulfonamide hematuria frequency of injury to the urinarytract as estimated on the basis of 6,084 cases treated with different sulfonamide preparations. Acta medica Scandinavica. 1950 138(4) 301-14. 

Renal stone formation, possibly also accompanied by intratubular precipitation of crystalline material, has been arare complication of drug therapy. Until the AIDS era, triamterene had been the drug most frequently associated with renal stone formation, with an incidence approximating 1 in 1500 users of triamterene-hydrochlorothiazide. However, it has been unclear whether triamterene or its metabolites actually initiated stone formation, or are passively absorbed onto the organic matrix of pre-existing calculi. Sulfadiazine is a poorly soluble sulfonamide that has caused symptomatic acetylsul-fadiazine crystalluria with stone formation and flank or back pain, hematuria, or renal insufficiency in up to 29% of patients treated with the drug. A high urine volume and urinary aUcalinization to... 

Fewer than 0.1% of patients receiving sulhsoxazole suffer serious toxic reactions. The untoward effects prodnced by this agent are similar to those that follow the administration of other sulfonamides. Because of its relatively high solubility in the urine as compared with sulfadiazine, sulhsoxazole only infrequently produces hematuria or crystalluria (0.2 to 0.3%). Despite this, patients taking this drug should ingest an adequate quantity of water. Sulhsoxazole and all snlfonamides that are absorbed must be used with caution in patients with impaired renal function. Like all sulfonamides, sulhsoxazole may produce hypersensitivity reactions, some of which are potentially lethal. Sulhsoxazole currently is preferred over other snlfonamides by most clinicians when a rapidly absorbed and rapidly exaeted sulfonamide is indicated. 

Gastrointestinal distress frequently is caused by doses greater than 500 mg fom times a day, even with enteric-coated tablets. Painful and frequent micturition, albuminuria, hematuria, and rashes may result from doses of 4 to 8 g/day given for longer than 3 to 4 weeks. Once the urine is sterile, a high dose should be reduced. Because systemic methenamine has low toxicity at the typically used doses, renal insufficiency does not constitute a contraindication to the use of methenamine alone, but the acids given concurrently may be detrimental. Methenamine mandelate is contraindicated in renal insufficiency. CrystaUuria from the mandelate moiety can occur. Methenamine combines with sulfamethizole and perhaps other sulfonamides in the urine, which results in mutual antagonism. 

Nephrotoxicity Sulfonamides may precipitate in the urine at acidic pH, causing crystal-luria and hematuria. 

The most common adverse effect of sulfonamides is a skin I ash due to hypersensitivity. CNS effects and hematuria occur less frequently. Sulfonaiuides are usually avoided in the third... 

The majority of adverse effects to sulfonamides are mild in nature and reversible, although idiosyncratic drug reactions may occur. Urinary tract disturbances, including sulfonamide crystalluria and hematuria, can be minimized in susceptible animals by maintaining an adequate water intake to maintain a high urine flow. Bone marrow depression and dermatologic reactions have also been associated with sulfonamide therapy in animals. 

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