Examples of resistance in gram- bacteria/yeasts/fungi

egs of gram+ rods (6)

clostridioides difficile, costridium tetani, c botulinum, c perfringens; listeria monocytogenes, corynebacteriums spp

gram+ cocci egs + how do they look on the gram stain?

streptococcus spp (chains), staphylococcus spp (bunches)

egs of gram- rods (1 (4 subtypes), 2)

enterobacteriaceae (klebsiella, proteus, salmonella, e coli), haemophilus influenzae, pseudomonas spp

gram- rods label top to bottom

h influenzae, e. coli, c. jejuni, fusobacteria

gram- cocci egs (3)

neisseria gonorrhoeae, neisseria meningitidis, moraxella catarrhalis

gram- cocci - label top then bottom left then bottom right

m. catarrhalis, n. gonorrhoeae, n. meningitidis

MDR gram- bacteria - 3 egs

ESBL producing enterobacteriales, carbapenemase producing psuedomonas, carbapenemase producing acinetobacter

3 classes of beta lactams + some egs per class

penicillins - amoxicillin, cephalosporins - cefazoline, cefuroxim, ceftriaxon/ceftazidim, carbapenems - meropenem

spectrum of beta lactamases (3)

penicillinases, cefalosporinases, carbapenemases

beta lactamase decr

inducible, hydrolyze beta lactams

esbl long

extended spectrum beta lactamase

esbl - what is it resistant to

all penicillins, all cefalosporins (1st, 2nd and 3rd gen), often combined with resistance to other abx (plasmid)

eg where does overexpression of efflux pump happen

in MDR bacteria like pseudomonas or acinetobacter

6 ways of resistance to gram- bacteria

on plasmid: antibiotic degrading enzyme (eg betalactamse), antibiotic altering enzyme (eg aminoglycoside modifying enzyme);
overexpression of efflux pump, cell wall (eg van gene cluster results in low binding affinity in glycopeptides, inhibiting last stage of cell wall synthesis), reduce permeability (eg change in PBPs like in MRSA)

possible community sources of ESBL (4)

hospital and long term care facilities, food producing animals, raw vegetables, foreign travel

prevalence of ESBL in NL

about 8.5%

retail chicken meal - how much percent at least 1 e. coli ESBL positive?

94%

conclusion of the study on ESBL in meat?

suggestive for transmission of ESBL genes, plasmids and e. coli isolates from poultry to humans, most likely through the food chain

conclusion of ESBL producers in raw vegatables

presence of ESBL-producing enterobacteriaceae in some raw vegetables in amsterdam (6%), no e coli and more other species than those found to date in humans and meat in NL, genes comparable to those found in humans and meat

what is the prevalence of carbapenemases in NL?

very low

2 subtypes in ambler classification + egs for each class

serine - beta lactamases: class A (KPC), class C (eg AmpC), class D (eg OXA-48)
metallo-beta-lactamases: class B (eg NDM)

risk factors for hospital transmission of ESBL (2)

repatriation from foreign hospital, known carriage

contact isolation for ESBL/carbapenemases

1 person room, wash hands, lab coat, gloves - then contact w/ patient then lab coat and gloves in bin, wash hands, leave (less severe than w/ other things)

conclusion on ESBL/carbapenemase producing bacteria (6)

resistance due to enzymes, encoded on plasmids; prevalence increasing worldwide; in NL prevalence of ESBL 4-8% in community, carbapenemases <1%; found in raw vegetables and meat; prevalence high in patients repatriated from foreign hospitals/ICU; contact isolation

treatment options for Multiple resistant gram- bacteria (7 drugs + 2 general guidlines)

colistin, fosfomycin i.v., tigecyclin, minocyclin, aztreonam, ceftolozaan/tazobactam, ceftazidim/avibactam; combination therapy, high dose therapy

what to expect in the future with antibiotics (4 + egs)

new combination of beta lactam/beta lactam inhibitor tested in phase 3 studies (meropenem-vaborbactam, biapenem-varbobactam, imipenem-relebactam); a new aminoglycoside (plazomicine); a new flurocyclin (eravacycline (similar to tigecyclin but 2-4 times more active); a new siderphore cephalosporin (cefiderocol)

phage therapy descr

mainly used in georgia and russia, topical treatment of skin infections (eg against S. aureus), few articles - mostly case studies