Antiinfectives II

Question 1

Sulphanomides are

Answer 1

Complex synthetic organic chemical compounds
Bacteriostatic
Sulfanilamide is active agent
G+ and G- bacteria
Wide using
Plasmid mediated resistance
Bind to plasma albumin
Min. therapeutic conc. in blood 2-10%

Question 2

Mechanism of action of sulfanomides

Answer 2

Structural analogs of PABA
Inhibit dihydropteroate synthase
Reduce synthesis of dihydrofolic acid
Diminish levels of tetrahydrofolate
Suppression of protein synthesis
Impairment of metabolic processes
Inhibit microbial growth and multiplication
Bacteriostatic

Question 3

What can you combine sulfonamides with to make them bactericidal?

Answer 3

Trimethoprim

• separately they are bacteriostatic

Question 4

Standard use of sulfanomides

Answer 4

Upper and lower respiratory tract infections
Urogenital systems
Erysipelas, septicemia and pyemia
Secondary bacterial infections in viral diseases
Coccidosis

Question 5

Classify sulfanomides

Answer 5

Short-acting - above 50ug for less than 12 hours
Intermediate acting - 50ug between 12h-24h
Long acting - 50 ug obtained after 24h

Question 6

Classification of sulfanomides according to solubility

Answer 6

Highly soluble - UTI
Poorly soluble - ulcerative colitis in dogs

Question 7

Topical sulfanomides are used for

Answer 7

Ophtalmic infections, burn wounds

Question 8

Adverse and undesired effects of sulfanomides

Answer 8

Hepatitis, hypersensitivity, bone marrow depression
Nausea, vomiting, disorders of digestion and urinary tract
Low pH + incorrect administration - crystalluria
Cyanosis (MtHb)
Hemorrhagic syndrome (impact on vit. K synthesis)
Reduction of vit B synthesis (suppression on gut microflora)

Question 9

Quinolones and fluoroquinolones

Answer 9

Bactericidal
Inhibition of bacterial DNA synthesis
In vitro
High activity of microorganisms resistant to other antibiotics

Question 10

Mechanism of action of quinolones and fluoroquinolones

Answer 10

Quinolones: inhibit replication of bacterial DNA by blocking the ligase domain of bacterial DNA ligase

Fluoroquinolones: inhibit 2 enzymes involved in bacterial DNA synthesis

Question 11

Indications of quinolones

Answer 11

UTI: acute cystitis, preventive therapy of chronic infections
Enteric infections: shigellosis, bacterial enterocolitis

Question 12

Indications of fluoroquinolones

Answer 12

Upper respiratory tract infections
Enteric infections: shigellosis, typhoid fever, salmonellosis, yersiniosis, cholera
Anthrax
Infections of urogenital system
Infections of skin, soft tissue, bones and joints
Eye infections
Meningitis by G-
Sepsis
Tuberculosis