Hematuria sulfadiazine

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. 

Figure 1. Sulfadiazine nephrotoxicity (crystalluria and acute renal failure). 35 year old man with AIDS and cerebral toxoplasmosis treated for 33 days with 4-6 g/dayofsulfadiazine.The patient received oral hydration and possibly had an episode of transient renal impairment during days 8-13. By day 29 of treatment, crystalluria, hematuria, flank pain, renal calculi, and acute renal failure developed. Urine was alkalinized late in the course.

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. 

---