Skin Therapy - Pyoderma

Question 0

Which antibiotics are pseudintermedius resistant to UK?

Answer 0

• penicillin, oxytet highest
• lincomycin, erythromycin, trimethoprim low
• 1% to enrofloxacin and marbofloxacoin
• none to cefalexin, co-amoxiclav, oxacillin, meticillin
  > study 1980s, likely increased now

Question 1

2 methods of antiobiotic choice?

Answer 1

1. empirical
   - classical superficiial pyoderma/folliculitis = probably s. pseudintermedius
   - wet lesions = gram neg?
   - local knowledge sensitivity patterns

Question 2

What are some alternative method of antibacterial tx for superficial pyoderma?

Answer 2

Topical therapy
- antibacterial shampoo (combo or alone)
Clindamycin (Antirobe)
- some resistancre

Question 3

Most common deep pyoderma organisms?

Answer 3

• rods (pseudomonas) so not b lactams - fluoroquinolones better
• cocci (staph)- cefalexine

Question 4

Possible reasons for resistance?

Answer 4

> clinical 
- wrong dose
- compliance
- absorption
- underlying cause 
- resustance developed during tx
> bacteria 
- intrinsic resistance (natural trait) 
- acquired resistnace (mutations)

Question 5

What abx still gets multiresistnat bugs? MRSP

Answer 5

oxytet (but reserve for more serious infections than skin disease!!)

Question 6

Is MRSP more virulent than normal buugs?

Answer 6

NO

• just more difficult to treat
• may actually be weaker

Question 7

Which animals are at risk of MRSP infection?

Answer 7

• lots of vet visits and lots of abx use in the past

Question 8

Is rifampin lic ?

Answer 8

NO

Question 9

What ROA iss best for gentamycin?

Answer 9

Not systemic (nephrotox)

Question 10

Can MRSA spread to pets?

Answer 10

YEs

Question 11

Can MRSP spreadto people?

Answer 11

YES - refer owner to GP if treating animal case

Question 12

3 tx options for MRSP?

Answer 12

1. 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 )
2. topical tx alone
3. off lic (exotic abx)

Question 13

Which topical antimicrobial agents have proven efficacy against staph?

Answer 13

• fusidic acid (low MICs shown for MRSA/MRSP)
• chlorhexidine
• benzoyl

Question 14

Should vancomycin be used?

Answer 14

No!! save for human tx of MRSA

Question 15

WHat should be done before using exotics abx?

Answer 15

Get advice from uni etc.

- trerat environment etc.

Question 16

4 main things to do with skin disease to minimise resistance?

Answer 16

1. cytology
2. early culture
3. read the data sheet!!!
4. control spread! last case seen in the day, dont wait in waiting room etc.

Question 18

What empiral assumptions can be made when treating skin bacterial infections?

Answer 18

• classical superficial pyoderma/folliculitis probably S. intermedius
• wet lesions: G-ves?
• local knowledge sensitvity patterns

Question 19

Which ABx are s. pseudintermedius most and least resistant to?

Answer 19

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

Question 20

Alternatives to Abx tx in superifical pyoderma?

Answer 20

> 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)

Question 21

How can tx for deep pyoderma be chosen semi-empirically?

Answer 21

• 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!!!

Question 22

What is MRSP?

Answer 22

> methicillin-resistnace staphylococcus pseudintermedius

• gene encoding broad-spec B-lactam ABx resistance
• more resistant than MRSA
• 20% pseudintermedius submissions

Question 23

What type of infections may be caused by MRSP? Which species?

Answer 23

• dogs and cats
• sometimes horses and donkeys
  > superficial and deep pyoderma
  > septicaemia, UTI, pneumonia, wound infections

Question 24

Tx options for MRSP and other multi-drug resistnant skin pathogens?

Answer 24

1. systemic tx if in vitro susceptibility identified
   - MRSA: most cat and dog isolates susceptible to potentiated sulphonamides and tetracyclines (50% also to clindamycin)
2. topical tx only
3. offlicence tx with exotic ABx

Question 25

Egs of topical tx for multi-drug resistant pathogens?

Answer 25

- fusidic acid (low MICs shown for animals MRSA and MRSP recently) - chlorhexidine - benzoyl peroxide

Question 26

Egs of exotic Abx?

Answer 26

- apramycin - amikacin - vancomycin - chloramphenicol - rifampicin > do not use without advice

Question 27

What is convenia?

Answer 27

- long acting cephalosporin (==fluoroquinolones, G- coverage too) - cefovecin 80mg/cl reconstituted powder

Question 28

Indications of convenia in dogs?

Answer 28

> skin and soft tissue infections - pyoderma, wounds, abscess (s. intermedius, B-haemalytic strep, E. coli, P. multocida) > UTIs (E.Coli, proteus spp)

Question 29

Indications for convenia in cats?

Answer 29

> skin and soft tissue abscesses, wounds (P. multocida, fusobacterium spp. bacteroides spp., prevotella oralis, B-haemolytic strep, s. intermedius) > UTIs (E. coli)

Question 30

contraindications for convenia?

Answer 30

- 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