Amped up at the Cantina Extended Spectrum Penicillins

1.3 – “Amped up at the Cantina”: Exten Extended ded spectru spectrum m pe penicillins nicillins (A (Ampicillin, mpicillin, amoxic amoxicillin, illin, piperacillin, ticarcillin) & β-lac -lactamase tamase inhibitors (c (clavulanate, lavulanate, taz tazobactam, obactam, sulbactam) • β-lactam antibiotics contain a 4-membered β-lactam ring (ringed planet). Bacterial peptidoglycan cell wall is synthesized by repeating D-alanyl-D-alanine oligopeptides (coccoid Death Star with D-ALA scaffolding). PBPs remove terminal alanine in the process of forming crosslinks between peptides. β-lactams inhibit this transpeptidation reaction by covalently binding PBPs, preventing bacterial cell wall synthesis. Effective in actively growing cells. • Aminopenicillins: o Bactericidal. o Broad spectrum (prism with rainbow). Maintain penicillin spectrum plus expanded activity against GI & genitourinary Grods, e.g. E. coli. Not first line for the latter. o Amoxicillin (ammo box) ▪ β-lactamase sensitive (β-lactamase bouncer) ▪ Similar spectrum to ampicillin but has better bioavailability (Hans Cillin not wearing mask) ▪ Oral administration (Hans Cillin popping pills) ▪ Major indications: • HEENT infections (alien encapsulated by mask), including pharyngitis (red scarf around neck), otitis media, sinusitis (alien with drippy antennae), tonsillitis. d/t S. pneumoniae, Moraxella, H. influenzae (Hib biplane). • Lower respiratory infections, including PNA, d/t β-lactamase-negative Streptococcus spp. (α- and β-hemolytic strains only), S. pneumoniae, Staphylococcus spp., or H. influenzae. (Alien lungs) • Skin infections d/t β-lactamase-negative Streptococcus spp. (α- and β-hemolytic strains only), Staphylococcus spp., or E. coli. • H. pylori triple therapy, combined with clarithromycin and PPI (helicobacter helicopter) • Lyme disease in early stage or young children (Target: Robin of Ixodes – borrelia burgdorferi transmitted by Ixodes tick) o Ampicillin (cantina band has an amp) ▪ β-lactamase sensitive (β-lactamase bouncer) ▪ Similar spectrum to amoxicillin with decreased bioavailability (mask wearing band member). Resistance to isolated ampicillin use is common (band member kicking amp off stage) ▪ Indications: • Oral administration o Mild GI infections with sensitive strains (colonic stills behind bar) o Mild GU infections with sensitive strains o respiratory tract infections d/t non-penicillinase-producing H. influenzae and staphylococci, and streptococci, including S. pneumoniae. o Prophylaxis for encapsulated bacteria in asplenic patients (patron with spleen-shaped hole in shirt KO’d maskwearing patron) o Prophylaxis before dental procedures in patients at high risk for endocarditis (bar-fighter’s teeth flying) • IV administration for systemic infections (Ivy around lead guitar) o Susceptible G+ sepsis. o Endocarditis susceptible G+ organisms o Severe GI infections with susceptible organisms (colonic stills behind bar) o Bacterial meningitis d/t E. coli, group B streptococci, L. monocytogenes, and other G- bacteria (Neisseria meningitidis) (meningitis helmet). Consider Listeria with very old & very young patients who may need additional treatment o Anaerobic infections, including aspiration PNA (gas mask) o Enterococcus, although resistance is common (diplococcus drums). o UTIs d/t E. coli and P. mirabilis. • β-lactamase inhibitors: Clavulanate, sulbactam, & tazobactam (clarinet & back-to-back tambourines) o Prevent drug cleavage by β-lactamase (distracting β bouncer). Often combined with β-lactams to extend activity of penicillins o Amoxicillin/clavulanate (Augmentin®) o Ampicillin/sulbactam (Unasyn®) or tazobactam • Adverse effects o Skin rashes when prescribed in cases of acute viral illness, e.g. EBV (red lights around Epstein’s Bar) o Stevens-Johnson syndrome (red tengu mask sloughing off) o Augmentin one of the most common causes worldwide of drug induced liver injury • Piperacillin & ticarcillin (pipers with tiger stripes) o Paired with tazobactam & clavulanate, respectively. o Broad spectrum coverage includes anaerobic infections (gas masks) o Active against pseudomonas! Important to consider in hospital acquired infections (Mona Lisa)