Bugs & Drugs Flashcards
hemolytic anemia associated with G6PD deficiency can present with _______
fatigue and scleral icterus (yellow in eyes) with elevated lactate dehydrogenase and total bilirubin
patients with G6PD deficiency are susceptible to developing ____ when they are exposed to ____ drugs
hemolysis when they are exposed to oxidizing agents such as sulfonamides like sulfamethoxazole
trimethoprim and pyrimethamine mechanism
inhibits dihydrofolate reductase (folate synthesis need for DNA)
sulfonamides and dapsone mechanism
inhibits dihydropteroate synthase (folate synthesis needed for DNA)
aminoglycosides are commonly associated with what side effects?
ototoxicity (high frequency hearing loss) and nephrotoxicity
tetracyclines toxicity includes:
tooth discoloration, photosensitivity reactions and inhibition of bone growth in children
flouroquinolone toxicity includes:
achilles tendonitis
macrolides toxicity includes:
acute cholestatic hepatitis, eosinophilia and skin rashes
what are the aminoglycosides?
30s ribosomal subunit against gram negative rod infections. Cannot treat anaerobes bc requires O2 for uptake
“GNATS”
gentamicin, neomycin, amikacin, tobramycin, streptomycin
when combined with alcohol, ____ causes a disulfiram-like “hangover” reaction
metronidazole
buildup of acetylaldehyde
what are the fluoroquinolones?
end in “floxacin”
inhibit topo 2 (DNA gyrase)
bactericidal
against gram negative rods of urinary and GI tracts (including pseudomonas)
symptoms and treatment of trichomonas vaginitis
frothy, yellow-green foul smelling discharge. pear shaped trichomonads
metronidazole
symptoms and treatment of candida vulvovaginitis
thick, white, “cottage cheese” discharge.
pseudohyphae
treat with azoles
how does metronidazole work?
forms toxic free radical metabolites in the bacterial cell that damage DNA
bactericidal and antiprotozoal
what is the mechanism of resistance to aminoglycosides?
inactivation via enzymatic modification like acetylation, phosphorylation, adenylation etc.
what is the mechanism of resistance for vancomycin?
amino acid modification of D-Ala-D-Ala to D-Ala-D-Lac
what is the mechanism of resistance for penicillins?
structural change in transpeptidases (PBPs = penicillin binding proteins)
what is the mechanism of resistance against macrolides?
methylation of 23S rRNA-binding site to prevent the drug from binding
what are the penicillinase-resistant penicillins?
dicloxacillin, nafcillin, oxacillin
use “Naf” for staph! (except MRSA)
what is the mechanism for penicillinase-resistant penicillins?
similar to penicillin but has a narrow spectrum. Penicillinase resistant because bulky R groups block access of beta-lactamase to beta-lactam ring
aspergillus fumigatus
branching of septate hyphae, catalase positive
immunocompromised patients can get aspergillomas after TB infection
treat with voriconazole or echinocandins (2nd line)
cryptococcus neoformans
narrow budding, heavily encapsulated yeast. can see clear halo with india ink
found in soil and pigeon droppings
sores on penis can indicate ____
syphillis, confirm diagnosis with flourescent treponemal antibody test. treat with penicillin G
how do macrolides work?
inhibits protein synthesis by blocking translocation