Principles of Antimicrobial Therapy Flashcards
Clindamycin may cause a superinfection of Clostridium difficile, resulting in this condition:
Pseumembranous colitis
Targets of antimicrobials unique to microorganisms?
Cell wall enzymes
Bacterial ribosomes
Enzymes required for DNA synthesis and reproduction
Examples of drugs with a postantibiotic effect?
Aminoglycosides
Streptogamins
Quinolones
This drug targets TB active in macrophages:
Pyrazinamide
This drug targets TB inside cavitary lesions:
Streptomycin
These drugs targes TB inside marcophages, cavitary lesions and caseations:
Isoniazid and Rifampicin
Gram-type with high LPA, periplasmic space, and absent teichoic acids:
Gram Negative
Examples of virulence factors:
Pili
Certain K antigen types
Secretion of hemolysin and colicin V
This type of H. influenzae is more virulent than other strains
Haemophilus infulenzae
This type of Pneumococci is more virulent that other strains:
Encapsulated Pneumococci
This bacterial proteins have enzymatic activity that facilitate local tissue spread:
Protease Hyaluronidase Neuraminidase Elastase Collagenase
These organisms are capable of traversing intact eukaryotic cells:
Shigella flexneri
Yersinia enteroclitica
Acetyltransferases inactivate these drugs:
Chloramphenicol
Kinases and other enzymes inactivate these drugs:
Aminoglycosides
Antimicrobials contraindicated in patients with GP6D deficiency
Quinolones Sulfonamides and Sulfones Chloramphenicol Chloroquines Furazolidone Diaminopyrimidines
Drugs affected by variations in acetylation (fast and slow):
Isoniazid, Dapsone
These drugs may cause neural tube defects in babies:
Sulfonamides and sulfas prevent folic acid formation
This class of cellular structures are used to make small molecules like AA, nucleotides, and folate:
Class II
This class of cellular structures build larger molecules like proteins, nucleic acids, and peptidoglycans:
Class III
These drugs are inhibitors of cell wall synthesis:
Beta Lactams Bacitracin Cycloserine Vancomycin Imidazoles
These drugs inhibit the 50S Ribosomal RNA subunit:
Macrolides (Erythromycin) Chloramphenicol Fusidic Acid Lincosamides (23s RNA) Oxazolidinones (23s RNA)
These drugs inhibit the 30s Ribosomal RNA subunit:
Aminoglycosides
Tetracycline
These drugs inhibit DNA dependent RNA polymerase enzyme:
Quinolones
Rifampicin
These drugs weaken the cell membrane:
Polymixin (anti-fungal)
Imidazoles
Polyene antibiotics like Nystatin and Amphothericin
This is an example of an antimetabolite drug:
Trimethoprim and Sulfamethoxazole (cotrimoxazole)
These are nucleic acid analogues:
Ziduvidine
Ganciclovir
Acyclovir
Vidarabine
Microbicidal drugs:
Beta Lactams Quinolones Aminoglycosides Rifampicin Polypeptides Vancomycin
Microbiostatic drugs:
Chloramphenicol Macrolides Sulfonamides Linsosamides Tetracyclines Trimethoprim
Drugs with a narrow spectrum:
Penicillin G Aztreonam Vancomycin Trimethoprim 3rd Gen Cephalosporins Anti-staphylococcal penicillins
Drugs with an intermediate spectrum:
Aminoglycosides
Lincosamides
Macrolides
Sulfonamides
Drugs with a broad spectrum:
Aminopenicillins Chloramphenicol Tetracyclines 2nd Gen Cephalosporins Imipenem
Nephrotoxic drugs:
Aminoglycosides Polymixin Vancomycin Cephaloridine Tetracycline
Ototoxic drugs:
Aminoglycosides
Marcrolides
Vancomycin
Hepatotoxic drugs:
Rifampicin Pyrazinamide Isoniazid Tetracycline Erythromycin estolate
Hematologically toxic drugs:
Chloramphenicol
Sulfonamides
Neurotoxic drugs:
Aminoglycosides
Beta Lactams
Combinations with an extended antimicrobial spectrum:
Beta lactam + aminoglycosides
Penicillin + streptomycin
Amphotericin + flucytosine
Reasons for antimicrobial failure:
Incorrect spectrum Inadequate coverage Inadequate blood levels Poor tissue penetration Drug-drug interaction
Some unusual pathogens:
Legionella
Mycoplasma pneumonia
Chlamydia
Drug resistance is commonly acquired through not mutation but:
Horizontal transfer through transduction, transformation, and conjugation
Mutation for resistance to streptomycin:
ribosomal mutation
Mutation for resistance to quinolones:
gyrase or topoisomerase IV mutation
Mutation for resistance to rifampin:
RNA polymerase mutation
Mutation for resistance to linezolid:
ribosomal RNA mutation
