Pathogens

Question 1

Tetracycline resistance in Staphylococci

Answer 1

Although the tet(M) gene confers resistance to all agents in the class, tet(K) confers resistance to tetracycline [78] and inducible resistance to doxycycline [79], with no impact on minocycline susceptibility. Therefore, minocycline may be a potential alternative in such cases.

Question 2

Indications for adjunctive abx in abscess

Answer 2

Severe/extensive disease or progression;
Signs/sxs of systemic illness;
Comorbidities/immunosuppression;
Extremes of age;
Face/hand/genitals;
Septic phlebitis;
Lack of response to I and D

Question 3

Recurrent SSTI disease definition

Answer 3

exists, most experts define recurrent disease as 2 or more discrete SSTI ep- isodes at different sites over a 6-month period

Question 4

MRSA decolonization procedures

Answer 4

Nasal decolonization with mupirocin twice daily for 5–10 days (C-III). ii. Nasal decolonization with mupirocin twice daily for 5– 10 days and topical body decolonization regimens with a skin antiseptic solution (eg, chlorhexidine) for 5–14 days or dilute bleach baths. (For dilute bleach baths, 1 teaspoon per gallon of water [or ¼ cup per ¼ tub or 13 gallons of water] given for 15 min twice weekly for !3 months can be considered.) (C-III).

Oral antimicrobial therapy is recommended for the treatment of active infection only and is not routinely recommended for decolonization (A-III). An oral agent in combination with rifampin, if the strain is susceptible, may be considered for decolonization if infections recur despite above measures

measures. If prescribed for decolonization, the optimal regimen and dura- tion is unknown, although a rifampin-based combination (eg, with TMP-SMX or doxycycline) is suggested and administered in short courses (eg, 5–10 days) to decrease the potential for development of resistance.

Question 5

Exclusions for uncomplicated MRSA bacteremia

Answer 5

No endocarditis;
No implanted prostheses;
F/u blood cx negative by 2-4 days;
Defeverscence within 72h of effective therapy;
No metastatic sites of infection

Question 6

Indications for empiric MRSA coverage for HAP (per MRSA guidelines)

Answer 6

For hospitalized patients with severe community-acquired pneumonia defined by any one of the following: (1) a requirement for ICU admission, (2) necrotizing or cavitary infiltrates, or (3) empyema, empirical therapy for MRSA is recommended pending sputum and/or blood culture results

Question 7

MRSA guidelines rec for persistent MRSA bacteremia on vancomycin

Answer 7

High-dose daptomycin (10 mg/kg/ day), if the isolate is susceptible, in combination with another agent (e.g. gentami- cin 1 mg/kg IV every 8 h, rifampin 600 mg PO/IV daily or 300-450 mg PO/IV twice daily, linezolid 600 mg PO/IV BID, TMP-SMX 5 mg/kg IV twice daily, or a beta-lactam antibiotic) should be considered

median time to clearance of MRSA bacteremia is 7–9 days [49, 172], most experts agree that per- sistent bacteremia at or around day 7 of therapy should prompt an assessment to determine whether a change in therapy is in- dicated.