Pharm Miscellaneous Antimicrobial Agents And &urinary Antiseptics

Front 1

Question: Infections caused by gram-negative bacilli have occurred when this cationic surfactant has been used as a skin antiseptic.

Back 1

Benzalkonium chloride.

Note: Pseudomonas can form a film on the skin under which microorganisms can survive.

Front 2

Question: A PT has intense abdominal pain of 2 d duration, and has spread to the RLQ with nausea, vomiting, and fever. BP 85/45, pulse 120, temp 40c. Abdomen is board-like rigidity with diffuse pain to palpation. WBC is 20,000 and creatinine 1.5. Abdominal sepsis is made, possibly from bowel perforation. PT is started on IV ampicillin and gentamicin.

Regarding this PT, what is true?

Question: If the antibiotic regimen is modified to include metronidazole, what should occur?

Back 2

A drug active against anaerobes should be included in the antibiotic regimen. Most likely abdominal sepsis pathogens: Bacteroides fragilis, Enterobacteriaceae, and Enterococcus faecalis.

Active drug would be: metronidazole, cefoxitin, cefotetan, or clindamycin.

The PT should be monitored for candidiasis, which frequently occur when treated with metronidazole.

Front 3

Question: What is used topically to treat scabies and pediculosis?

Back 3

Lindane. Permethrin is an alternative agent.

Front 4

Question: Methenamine salts are used as urinary antiseptics. the reason they lack systemic antibacterial action is that they are?

Back 4

Converted to formaldehyde only at a low pH.

Front 5

Question: What statement about the actions of antimicrobial agents is true?

Back 5

Daptomycin has activity against straints of staphylococci resistant to vancomycin.

Neonatal gonococcal opthalmia can be prevented by silver nitrate.

Salicylic acid has useful antidermatophyte activity when applied topically.

Polymyxins act as cationic detergents to disrupt bacterial cell mm.

Front 6

Question: What antiseptic promotes wound healing?

Back 6

No antiseptic in current use is able to promote wound healing, most agents do the opposite.

Front 7

Question: A 22 year old man with gonorrhea is to be treated with cefixime and will need another drug to provide coverage for possible urethritis caused by C trachomatis. Which of the following drugs is least likely to be effective in nongonococcal urethritis: azithromycin, ciprofloxacin, erythromycin, nitrofurantoin, and tetracycline.

Back 7

Nitrofurantoin.

Note: it is also effective in UTIs except for Pseudomonas aeruginosa Proteus.

Front 8

Question: A PT with AIDS has an extremely high viral RNA titer. While blood is being drawn from this PT, the syringe is accidentally dropped, contaminating the floor, which is made of porous material. The best way to deal with this is to?

Back 8

Clean the four with a 10% solution of household bleach., which has sodium hypochlorite.

Front 9

Question: This compound is used in tablet form to purify drinking water. If a large quantity of organic material is present, cysts of Entamoeba histolytica may not be eradicated.

Back 9

Halazone, which will sterilize most water samples but will not kill cysts of Entamoeba histolytica.

Front 10

Question: Daily use of this substituted phenol results in a bacteriostatic deposit on the skin. The compound may be absorbed and has caused neurotoxic effects in neonates when used as an anti-staphylococcal agent.

Back 10

Hexachlorophene.

Note: repeated bathing of newborns with hexachlorophene to prevent staph colonization may permit systemic absorption, which leads to neurotoxic effects (eg, spongiform degeneration of white matter)

Front 11

Question: Neuropathies are more likely to occur with this agent when it is used in PTs with renal dysfunciton. The drug may cause acute hemolysis in PTs with glucose-6-phosphate dehydrogenase (G6PD) deficiency.

Back 11

Nitrofurantoin

Note: G6PD deficiency occur with drugs that are oxidizing agents, including: antimalarials, nalidixic acid, sulfonamides, and nitrofurans.

Nitrofurantoin also causes both motor and sensory nerve degeneration.

Front 12

Question: This agent is commonly incorporated into soaps used for skin antisepsis and surgical scrub procedures. The compound has minimal activity against Pseudomonas and Serratia.

Back 12

Chlorhexidine

Front 13

Question: A urinary antiseptic, this agent is not effective in the treatment of urinary tract infections caused by Proteus. Mutual antagonism may occur if this drug is used concomitantly with sulfonamides.

Back 13

Methenamine

It releases formaldehyde at acidic pH.

Proteus alkalinize the urine, preventing the release of formaldehyde.

Front 14

Question: Consumption of ethanol together with this drug causes nausea, vomiting, abdominal cramps, flushing, and headache in some PTs.

Back 14

Metronidazole.

Inhibits aldehyde dehydrogenase and may cause disulfiram-like reaction with alcohol.

Front 15

What is the MOA of metronidazole and tinidazole?

SE

Back 15

The drug undergoes reductive bioactivation of their nitro group by ferredoxin (present in anaerobic parasites) to form reduced reactive cytotoxic compounds that damages DNA and nucleic acid synthesis.

Disulfiram-like reaction with ethanol, metallic taste.

Front 16

What is metronidazole effective against?

Back 16

Anaerobic bacteria: Clostridium and Bacteroides species.

Protozoans: Giardia, Entamoeba, Trichomonas, Gardnerella vaginalis.

DOC for pseudomembrane colits.

Is used also for H. pylori infection.

Front 17

GET GAP on the Metro

Back 17

Giardia, Entamoeba, Trichomonas, Anaerobes (Bacteroides, Clostridium) h. Pylori.

Front 18

What is the MOA of polymyxins?

Back 18

These drugs act like cationic detergents, disrupting bacterial cell mm and increasing permeability of cell mm to polar molecules.

Front 19

What is polymyxins used for and their SE?

Back 19

Because of their toxicity (acute renal tubular necrosis and neurotoxicity), they are used only topically to treat infected skin lesions of resistant gram-negative rods.

Front 20

What is the purpose behind urinary antiseptics and name three of them.

Back 20

The drugs lack systemic antibacterial effects but may be toxic. They are often administered with acidifying agents because low pH is an independent inhibitor of bacterial growth in urine.

Nitrofurantoin, nalidixic acid, methenamine.

Front 21

What is nitrofurantonin used for and its SE.

Back 21

UTIs (but not for Proteus or Pseudomonas).

Hemolysis in PTs with glucose-6-phosphate dehydrogenase (G6PD) deficiency, pulmonary infiltrates, phototoxicity, neuropathies.

Front 22

What is nalidixic acid used for?

Back 22

It is rarely used since it is excreted rapidly. It is a quinolone drug used against gram-negative (but not Proteus or Pseudomonas).

Front 23

Methenamine MOA?

Back 23

Forms formaldehyde in urine, and is not effective against Proteus.

Front 24

What is the difference between a disinfectant and an antiseptic?

Back 24

Disinfectant kills microorganisms in an inanimate environment.

Antiseptic inhibits bacterial growth both in vitro and in contact with the surfaces of living tissue.

Front 25

Ethanol and isopropanol

Formaldehyde

Acetic acid

Salicylic acid and undecylenic acid

Back 25

Skin antiseptic since they denature microbial proteins.

Too irritating for topical use, but a disinfectant for instruments.

Surgical dressing, active against gram-negatives including Pseudomonas.

Dermatophyte infections

Front 26

Iodine tincture

Hypochlorous acid

Back 26

Antispetic for preparing the skin before taking blood samples.

Forms chlorine in water that prevents antimicrobial actions.

Active component in bleach. Disinfection of blood spill that may contain HIV or HBV.

Front 27

Hydrogen peroxide

Potassium permangante

Back 27

Releases molecular O2. Used for mouthwash, cleaning wounds, disinfection of contact lenses.

Effective bactericidal agent,b ut leaves persistent brown stains on skin and clothing.

Front 28

Mercury and silver

Nitromersol and thimerosal

Merbromin

Silver nitrate

Silver sulfadiazine

Back 28

Rarely used because of toxicity. Inactivates sulfhydryl groups of enzymes and precipitate proteins

Preservatives for vaccines, antitoxins, and immune sera.

Weak antiseptic and stains tissues bright red

replaced by topical antibiotics

A sulfonamide, used to decrease bacterial colonization in burns.

Front 29

What are the chlorinated phenols and their uses?

Back 29

Phenol: due to its toxicity, disinfectant of inanimate objects

Hexachlorophene: used in surgical scrub routines and deodorant soaps to decrease resident bacteria. Repeated use can cause CNS white matter degeneration.

Chlorhexidine: gram-positive cocci, used in hospital scrub routines.

Note: all antiseptic soaps can cause allergies or photosensitization.

Front 30

What are some ectoparasiticides?

Back 30

Lindane: used for mites or lice, and agricultural insecticide. Can cause blood dyscrasias and convulsions. Crotamiton is an alternative to lindane.

Permethrin: topically for pediculosis and scabies.

Malathion: organophosphate cholinesterase inhibitor, used topically in pediculosis.

Front 31

What are two cationic surfactants, and what has the CDC said about it?

Back 31

Benzalkonium chloride and cetylpyridinium chloride: disinfectants of surgical instruments and surfaces such as floors and bench tops.

Not to be used as antiseptics because outbreaks of infection have resulted from growth of gram-negative bacteria (e.g., Pseudomonas) in such antiseptic solutions.