Master Sulfonamides Mechanisms with Picmonic for Medicine

Gram-positive organisms absorb the crystal violet stain due to the thick peptidoglycan layer in the cell wall. Examples of Gram-positive microorganisms include Staphylococcus and Streptococcus species. Due to their mechanism of action, sulfonamides are active against a wide spectrum of bacteria, including both Gram-positive and Gram-negative organisms.

Gram-negative organisms do not stain with crystal violet due to a relatively thin peptidoglycan layer in the cell wall. Due to their mechanism of action, sulfonamides are active against a wide spectrum of bacteria, including Gram-negative organisms.

Nocardia is a Gram-positive rod that forms beaded, branching filaments that resemble fungi. It is weakly acid-fast and classically presents in immunocompromised patients as lung cavitations or brain and kidney infections. Nocardia is classically treated with a sulfonamide antibiotic.

Chlamydia trachomatis is an obligate intracellular human pathogen composed of multiple serovars that cause distinct clinical syndromes: serovars A-C lead to trachoma; serovars D-K cause urogenital infections such as urethritis, cervicitis, and pelvic inflammatory disease; and serovars L1-L3 are responsible for lymphogranuloma venereum. The recommended treatment for infections caused by Chlamydia trachomatis, as well as Chlamydia pneumoniae and Chlamydia psittaci, is doxycycline, with macrolides such as azithromycin serving as effective alternatives.

Sulfonamides are structural analogs and competitive antagonists of para-aminobenzoic acid (PABA) and compete with para-aminobenzoic acid (PABA) for incorporation into folic acid. Incorporation of sulfonamides causes inhibition of the enzyme dihydropteroate synthase in the folic acid synthesis pathway. Because folic acid is necessary for vital cell functions like DNA synthesis, bacteria that are deprived of folate will eventually die.

Sulfonamides are structural analogs and competitive antagonists of para-aminobenzoic acid (PABA) and compete with para-aminobenzoic acid (PABA) for incorporation into folic acid. Incorporation of sulfonamides causes inhibition of the enzyme dihydropteroate synthase in the folic acid synthesis pathway. Because folic acid is necessary for vital cell functions like DNA synthesis, bacteria that are deprived of folate will eventually die.

Sulfamethoxazole is a sulfonamide antibiotic most often used as part of a synergistic combination with trimethoprim, commonly abbreviated as TMP-SMX or known under trade names like Bactrim. It is primarily used against susceptible forms of Staphylococcus and Streptococcus species, E. coli, and oral anerobes.

Sulfisoxazole is a sulfonamide antibiotic with an oxazole component. This antibiotic has activity against a wide range of Gram-positive and Gram-negative organisms, like the other sulfonamide antibiotics.

Sulfadiazine is a sulfonamide antibiotic that is used in combination with pyrimethamine to treat toxoplasmosis. It is also commonly used to treat urinary tract infections.