Therapeutics of Mid-Hindgut Infections Flashcards
What is the use of Metronidazole and Tinidazole? what are acute and longterm adverse fx
Antiprotozoal and anti-obligate anaerobes (kills trophozoites, not cysts)
adverse fx
acute: nausea, diarrhea, alcohol intolerance, sleep disturbances
chronic - peripheral neuropathy, encephalopathy
What is the mechanism of fluoroquinolones? how is resistance mediated? Adverse Fx?
Ciprofloxacin, Levofloxacin
DNA gyrase inhibition (prevents transcription)
Resistance: plasmid mediated
adverse fx: long QT interval (arrhythmia), arthropathy (dont use in pts under 18)
What are 3 macrolides? mechanism? resistance? Metabolism/excretion? Adverse fx?
Erythromycin, Clarithromycin, Azithromycin (longest half life)
50s inhibitors (bacteriostatic)
resistance: plasmid mediated
Met: P-450
Excr: Excreted in bile
Adverse fx: Erythromycin can cause Cholestatic hepatitis
What drug group is Clindamycin in? What are adverse fx?
Macrolide-like
adverse fx: Impaired liver fxn, C. DIFF INFECTION
What is the mechanism of Vancomycin? What are adverse fx? uses?
Glycopeptide Abx: prevents cross-linking (bactericidal)
Uses: Abx a/w Colitis
adverse fx:
Red man syndrome - histamine release (flushing)
Ototoxicity
Renal toxicity
What bacteria most commonly causes Traveler’s Diarrhea? what is transmission? What are risk factors?
E. Coli (Montezuma revenge) Food borne (fecal-oral): self limiting (3-7 days) Risks: Most significant = Travel Destination (S. America, Africa, Asia) H2 blockers, PPI's H. pylori immunocompromised age (very young, old)
When do you prescribe Abx for Travelers Diarrhea? What 2 Abx are they?
> 4 loose stools a day w/:
fever, blood/pus/mucus in stools
Fluoroquinolones (Ciprofloxacin)
Macrolides (Azithromycin, Rifaximin)
What is transmission and Sx of Shigella? and treatment?
Fecal oral Diarrhea + Hemolytic Uremia Tx: rehydration primary: Fluoroquinolone secondary: Azithromycin
What is transmission of Salmonella? and treatment?
fecal oral
Tx:
drug resistant = Ceftriaxone
secondary: Azithromycin
How does Vibrio cholera cause diarrhea? what is primary and secondary therapy? what is transmission?
Oral-fecal - toxin mediated diarrhea Tx: Primary: Oral rehydration Secondary: Macrolides (Azithromycin, Erythromycin) then: fluoquinolones, tetracyclines
How does Death from bacillary diarrheas usually occur? which 2 bacteria are the most severe?
Dehydration + electrolyte imbalances
Salmonella typhi
Vibrio Cholera
Where is Giardia common? What is Tx for normal and pregnancy?
common in developed and under developed world
Tx: Metronidazole, Nitazoxanide, Albendazole
Pregnancy: Paromomycin
What is the life cycle for giardia?
Cyst is ingested
becomes trophozoite and multiplies in small bowel
becomes cyst and excreted in poop
*cysts can also come from COWS
What are Sx of Cryptosporidia? What is Tx?
Watery diarrhea, infxn goes away within week or two
one celled parasite burrows into intestine wall
Tx: Nitazoxanide, Parmomomycin
What are Sx of Cyclospora? Tx? how is it contracted?
Water/Explosive diarrhea, fever, muscle aches
Tx: Sulfamethoxazole, Trimethoprim
oocysts in water/food
