Skin Therapy - Pyoderma Flashcards
Which antibiotics are pseudintermedius resistant to UK?
- penicillin, oxytet highest
- lincomycin, erythromycin, trimethoprim low
- 1% to enrofloxacin and marbofloxacoin
- none to cefalexin, co-amoxiclav, oxacillin, meticillin
> study 1980s, likely increased now
2 methods of antiobiotic choice?
- empirical
- classical superficiial pyoderma/folliculitis = probably s. pseudintermedius
- wet lesions = gram neg?
- local knowledge sensitivity patterns
What are some alternative method of antibacterial tx for superficial pyoderma?
Topical therapy
- antibacterial shampoo (combo or alone)
Clindamycin (Antirobe)
- some resistancre
Most common deep pyoderma organisms?
- rods (pseudomonas) so not b lactams - fluoroquinolones better
- cocci (staph)- cefalexine
Possible reasons for resistance?
> clinical - wrong dose - compliance - absorption - underlying cause - resustance developed during tx > bacteria - intrinsic resistance (natural trait) - acquired resistnace (mutations)
What abx still gets multiresistnat bugs? MRSP
oxytet (but reserve for more serious infections than skin disease!!)
Is MRSP more virulent than normal buugs?
NO
- just more difficult to treat
- may actually be weaker
Which animals are at risk of MRSP infection?
- lots of vet visits and lots of abx use in the past
Is rifampin lic ?
NO
What ROA iss best for gentamycin?
Not systemic (nephrotox)
Can MRSA spread to pets?
YEs
Can MRSP spreadto people?
YES - refer owner to GP if treating animal case
3 tx options for MRSP?
- systemic tx if in vitro susceptability proven (rarely with MRSP, for MRSA most cat/dog strains susceptible to potentialted sulphonamidees and tetracyclines, 50% to clindamycin )
- topical tx alone
- off lic (exotic abx)
Which topical antimicrobial agents have proven efficacy against staph?
- fusidic acid (low MICs shown for MRSA/MRSP)
- chlorhexidine
- benzoyl
Should vancomycin be used?
No!! save for human tx of MRSA
WHat should be done before using exotics abx?
Get advice from uni etc.
- trerat environment etc.
4 main things to do with skin disease to minimise resistance?
- cytology
- early culture
- read the data sheet!!!
- control spread! last case seen in the day, dont wait in waiting room etc.
What empiral assumptions can be made when treating skin bacterial infections?
- classical superficial pyoderma/folliculitis probably S. intermedius
- wet lesions: G-ves?
- local knowledge sensitvity patterns
Which ABx are s. pseudintermedius most and least resistant to?
1988 study (so will have ^ now)
- no resisntace to cefalexin, co-amoxiclav, oxacillin, metacillin
- 1% resistnace to enrofloxacin and marbofloxacin
- low resistnace to trimethoprim, erythromycin, lincomycin
- medium resistnace to oxytetracycline
- high resistance to penicillin
Alternatives to Abx tx in superifical pyoderma?
> Clindamycin (Antirobe)
- narrow-spec
- topical antibacterial shampoos
- in combination or alone
- products with proven efficacy (chlorhexidine, benzoyl peroxide)
- owner compliance (2x weekly bathing, min 10mins contact time)
How can tx for deep pyoderma be chosen semi-empirically?
- 60-80% pseudintermedius
- alwways culture
- while waiting for lab results (~1 week) tx based on cytology
> cocci: cefalexine
> rods: fluoroquinolones - duration of tx many weeks, at least 2 weeks beyong clinical cure!!!
What is MRSP?
> methicillin-resistnace staphylococcus pseudintermedius
- gene encoding broad-spec B-lactam ABx resistance
- more resistant than MRSA
- 20% pseudintermedius submissions
What type of infections may be caused by MRSP? Which species?
- dogs and cats
- sometimes horses and donkeys
> superficial and deep pyoderma
> septicaemia, UTI, pneumonia, wound infections
Tx options for MRSP and other multi-drug resistnant skin pathogens?
- systemic tx if in vitro susceptibility identified
- MRSA: most cat and dog isolates susceptible to potentiated sulphonamides and tetracyclines (50% also to clindamycin) - topical tx only
- offlicence tx with exotic ABx
Egs of topical tx for multi-drug resistant pathogens?
- fusidic acid (low MICs shown for animals MRSA and MRSP recently)
- chlorhexidine
- benzoyl peroxide
Egs of exotic Abx?
- apramycin
- amikacin
- vancomycin
- chloramphenicol
- rifampicin
> do not use without advice
What is convenia?
- long acting cephalosporin (==fluoroquinolones, G- coverage too)
- cefovecin 80mg/cl reconstituted powder
Indications of convenia in dogs?
> skin and soft tissue infections - pyoderma, wounds, abscess (s. intermedius, B-haemalytic strep, E. coli, P. multocida)
UTIs (E.Coli, proteus spp)
Indications for convenia in cats?
> skin and soft tissue abscesses, wounds (P. multocida, fusobacterium spp. bacteroides spp., prevotella oralis, B-haemolytic strep, s. intermedius)
UTIs (E. coli)
contraindications for convenia?
- hypersesntivity to cephalopsporins or penicillin
- small mammals (guinaepigs, rabbits)
- dogs and cats < 8 weeks
> reserve 3rd gen cephalosporins for cases with c+s and failure or expected failure to respons to other drugs
