Anemias sulfonamides causing

The answer is a. (Katzung, p 162.) Many drugs can cause an immunohemolytic anemia. Methyldopa may cause a positive Coombs test in as many as 20% of patients, along with hemolytic anemia. Other drugs with similar actions on red blood cells are penicillins, quinidine, procainamide, and sulfonamides. These form a stable or unstable hapten on the red cell surface, which induces an immune reaction I immunoglobulin G (IgG) antibodies] and leads to dissolution of the membrane. 

The answers are 484-k 485-j. (tlardman, pp 1061-1062, 1682-1685.) Sulfonamides can cause acute hemolytic anemia. In some patients it mayr be related to a sensitization phenomenon, and in other patients the hemolysis is due to a glucose-6-phosphate dehydrogenase deficiency Sulfamethoxazole alone or in combination with trimethoprim is used to treat UTls. The sulfonamide sulfasalazine is employed in the treatment of ulcerative colitis. Daps one, a drug that is used in the treatment of leprosy, and primaquine, an anti mala rial agent, can produce hemolysis, particularly in patients with a glucose-6-phosphate dehydrogenase deficiency. 

Severe reactions Severe reactions including deaths caused by sulfonamides have been associated with hypersensitivity reactions, agranulocytosis, aplastic anemia, other blood dyscrasias, and renal and hepatic damage. Irreversible neuromuscular and CNS changes and fibrosing alveolitis may occur. 

Caution [B (D if near term), M] Contra Sulfonamide or salicylate sensitivity, porphyria, GI/GU obst avoid in hepatic impair Disp Tabs SE GI upset discolors urine dizziness, HA, photosens, oligospermia, anemias, Stevens-Johnson synd Interactions T Effects OF oral anticoagulants, oral hypoglycemics, MTX, pheny-toin, zidovudine X effects W/ antibiotics X effects OF digoxin, folic acid, Fe, procaine, proparacaine, sulfonylureas, tetracaine EMS T Effects of anticoagulants monitor EGG and BP for signs of hypovolemia and electrolyte disturbances d/t D skin urine may become yellow-orange may stain contact lenses T risk of photosensitivity Rxns OD May cause NA, drowsiness, HA, abd pain, skin Rxns, lactic acidosis, and jaundice symptomatic and supportive... 

Serious adverse effects are rare except in AIDS patients. TMP-SMX can cause the same adverse effects as those associated with sulfonamide administration, including skin rashes, central nervous system (CNS) disturbances, and blood dyscrasias. Blood dyscrasias, hepatotoxicity, and skin rashes are particularly common in patients with AIDS. Most of the adverse effects of this combination are due to the sulfamethoxazole component. Trimethoprim may increase the hematological toxicity of sulfamethoxazole. Long-term use of trimethoprim in persons with borderline foUc acid deficiency, such as alcoholics and the malnourished, may result in megaloblastic anemia, thrombocytopenia, and granulocytopenia. 

Sulfonamides can cause hemolytic or aplastic anemia, granulocytopenia, thrombocytopenia, or leukemoid reactions. Sulfonamides may provoke hemolytic reactions in patients with glucose-6-phosphate dehydrogenase deficiency. Sulfonamides taken near the end of pregnancy increase the risk of kernicterus in newborns. 

Trimethoprim produces the predictable adverse effects of an antifolate drug, especially megaloblastic anemia, leukopenia, and granulocytopenia. The combination trimethoprim-sulfamethoxazole may cause all of the untoward reactions associated with sulfonamides. Nausea and vomiting, drug fever, vasculitis, renal damage, and central nervous system disturbances occasionally occur also. Patients with AIDS and pneumocystis pneumonia have a particularly high frequency of untoward reactions to trimethoprim-sulfamethoxazole, especially fever, rashes, leukopenia, diarrhea, elevations of hepatic aminotransferases, hyperkalemia, and hyponatremia. 

Some ADRs are caused by most or all medications in a class, while others are agent specific. Nausea, vomiting, and diarrhea have been observed with most antibiotics, yet only chloramphenicol and certain sulfonamide antibiotics have been consistently implicated as causes of aplastic anemia. Some pharmacological effects, such as sedation from an antihistamine, may be considered adverse effects when they are... 

Severe adverse drug reactions with trimethoprim and co-trimoxazole are rare (12-14). This also applies to children (15). The adverse effects of co-trimoxazole correspond to those expected from a sulfonamide (16). In HIV-infected patients, adverse effects of co-trimox-azole are more frequent and more severe (17-19). Hematological disturbances due to co-trimoxazole include mild anemia, leukopenia, and thrombocytopenia, which may be due to folic acid antagonism. Serious metabolic disturbances that are associated with trimethoprim include hyperkalemia and metabolic acidosis. Trimethoprim can cause hypersensitivity reactions. However, with co-trimoxazole, the sulfonamide is generally believed to be more allergenic (12). Generalized skin reactions predominate. Other effects, such as anaphylactic shock, are extremely rare (20-22). Carcinogenicity due to trimethoprim or co-trimoxazole has not been reported. 

These compounds were extensively used in the 40 s through the 60 s to treat pulmonary and other systemic infections. Reports of acute renal failure, most secondary to crystalluria were common [1-3]. Rarely, the sulfonamides can cause acute interstitial nephritis, necrotizing arteritis or hemoglobinuric acute renal failure due to massive acute hemolytic anemia [4, 6]. 

Hematotoxicity Though such effects are rare, sulfonamides can cause granulocytopenia, thromboc3Topenia, and aplastic anemia. Acute hemolysis may occur in persons with glu-cose-6-phosphate dehydrogenase deficiency. 

F. Toxicity of Trimethoprim Trimethoprim may cause the predictable adverse effects of an antifolate dmg, including megaloblastic anemia, leukopenia, and granulocytopenia. These effects are usually ameliorated by supplementary folinic acid. The combination of trimethoprim-sulfamethoxazole may cause any of the adverse effects associated with the sulfonamides. AIDS patients given TMP-SMZ have a high incidence of adverse effects, including fever, rashes, leukopenia, and diarrhea. 

In humans, folic add avitaminosis is more often caused by faulty uptake and/or utilization, than by dietary deficiency. It usually results in blood ab-normtilities, e.g. megablastic anemia and thrombocytopenia. Antimetabolites of folic acid are aminop-terin and methopterin, which are used therapeutically in the treatment of leukemia. The sulfonamides are antimetabolites of p-aminobenzoic acid, and therefore act as inhibitors of bacterial folic acid synthesis. 

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