Oral Antibiotic Options for Methicillin-resistant
Staphylococcus aureus (MRSA)
Methicillin-resistant
Staphylococcus aureus (MRSA) in
adults: Oral Treatment of Skin and Soft Tissue Infections (SSTI)
Patients with mild infection (localized involvement with no
systemic symptoms) due to known or suspected MRSA may be treated with oral
antibiotic therapy (kindly refer table below).
Oral antibiotic agents of choice include trimethoprim-sulfamethoxazole (TMP-SMX), tetracyclines
(such as doxycycline or minocycline), or clindamycin. In general, the choice between agents is guided
by individual clinical circumstances including local antibiotic resistance
patterns, allergy history, and concomitant medications.
The efficacy of clindamycin and TMP-SMX for treatment of uncomplicated
skin infection is comparable; in two randomized trials including patients with
uncomplicated skin infections, cure rates for clindamycin and TMP-SMX were
between 78 and 83 percent. Use of the tetracyclines is supported by
susceptibility testing and observational and retrospective reports; their
efficacy for treatment of skin and soft tissue infections due to MRSA has not
been rigorously evaluated or compared in clinical trials.
In the setting of empiric antibiotic therapy,
the efficacy of the above agents against the potential pathogen group A Streptococcus(GAS) should
be considered. Clindamycin and TMP-SMX are active against GAS; doxycycline has uncertain activity
Alternative oral agents include
oxazolidinones (linezolid and tedizolid), the fluoroquinolone delafloxacin, and the tetracycline omadacycline; use of these drugs is limited by cost, clinical
experience, and adverse drug effects. They should be reserved for patients who
do not respond to or cannot tolerate other agents.
Fluoroquinolones (apart from delafloxacin) should NOT be used for treatment of skin and soft tissue infections due to MRSA; resistance may develop during therapy.
Oral Treatment (in Adult)
|
Adult Dose (Normal Renal Function)
|
Clindamycin
|
450 mg orally 3 times daily
|
Doxycycline
|
100 mg orally twice daily
|
Linezolid
|
600 mg orally twice daily
|
Trimethoprim-sulfamethoxazole
(co-trimoxazole)*
|
1 or 2 DS tablets twice daily
|
* DS: double strength (ie, 160 mg
trimethoprim with 800 mg sulfamethoxazole per tablet).
|
|
MRSA Skin and Soft
Tissue Infections - Chahine
& Sucher (PSAP 2015)
TOPICAL Option
|
Dosing Regimen (Adults)
|
Dosing Regimen (Children)
|
Adverse Effects
|
Significant Drug Interactions
|
Mupirocin (ointment,
cream)
|
Skin infections for
adults and
children ≥ 2
months: Apply to affected area twice daily for 5 days
MRSA decolonization
for
adults and children
≥ 12
years: Apply to
anterior nares twice daily for 5 days
|
Hypersensitivity
reactions, skin
irritation,
pruritus, burning
|
-
|
|
SYSTEMIC Option
|
Dosing Regimen (Adults)
|
Dosing Regimen (Children)
|
Adverse Effects
|
Significant Drug Interactions
|
Clindamycin
|
300–450 mg PO
four times daily
Adults: 600 mg IV
three times daily
|
20–40 mg/kg/day IV/PO
divided into 3 doses
|
Clostridium difficile infection,
gastrointestinal
upset
|
-
|
Doxycyline
|
Adults and children
> 45 kg:
100 mg PO twice
daily
|
Children ≥ 8 years
and ≤ 45 kg:
2 mg/kg PO twice
daily
|
Gastrointestinal
upset,
photosensitivity,
permanent
tooth discoloration
in children
< 8 years, not
recommended for
pregnant women and
children <
8 years
|
Oral cations
|
Linezolid
|
Adults and children
≥ 12 years:
600 mg IV/PO twice
daily
|
Children < 12
years: 10 mg/
kg/day IV/PO twice
daily
|
Myelosuppression,
neuropathy,
serotonin syndrome
|
Serotonergic
agents
|
Trimethoprim/
Sulfamethoxazole
(Bactrim)
|
Adults: 1 to 2 DS
tablet(s) PO twice daily
|
8–12 mg/kg/day of
trimethoprim
divided into 4
doses IV or 2 doses
PO
|
Hypersensitivity
reactions,
nausea, vomiting,
myelosuppression,
hyperkalemia,
hepatotoxicity,
not recommended for
women in
the third trimester
of pregnancy
|
Warfarin,
renin-angiotensin aldosterone
system inhibitors
|
Vancomycin
(INTRAVENOUS)
|
30 mg/kg/day
divided into 2
doses
|
40 mg/kg/day
divided into 4
doses
|
Infusion reactions,
red man
syndrome,
nephrotoxicity
|
Nephrotoxic
agents
|
MRSA Infections
(Other Sites) - IDSA 2011
Manifestation
|
Treatment
|
Adult Dose
|
Paediatric Dose
|
Strength of Recommen-dation
|
Comment
|
Purulent cellulitis
(defined as
cellulitis
associated with
purulent
drainage or exudate
in
the absence of a
drainable
abscess)
|
Clindamycin
|
300–450 mg PO TID
|
10–13 mg/kg/dose PO
every
6–8 h, not to
exceed
40 mg/kg/day
|
AII
|
Clostridium difficile–associated
disease may occur
more
frequently,
compared with
other oral agents.
|
TMP-SMX
(Bactrim)
|
1–2 DS tab PO BID
|
Trimethoprim 4–6
mg/kg/dose,
PO BID
|
AII
|
TMP-SMX is pregnancy
category C/D and not recommended for women in the third trimester of pregnancy
and for children <2 months of age.
|
|
Doxycycline
|
100 mg PO BID
|
<45kg: 2 mg/kg/dose
PO BID .
45kg:
adult dose
|
All
|
Tetracyclines are
not recommended for children under 8 years of age and are pregnancy
category D.
|
|
Linezolid
|
600 mg PO BID
|
10 mg/kg/dose PO TID,
not to exceed 600 mg/dose
|
All
|
More expensive
compared
with other
alternatives
|
|
Nonpurulent
cellulitis
(defined as
cellulitis with
no purulent
drainage
or exudate and no
associated abscess)
|
Clindamycin
|
As above
|
|||
Linezolid
|
As above
|
||||
Complicated SSTI
|
Linezolid
|
600 mg PO/IV BID
|
10 mg/kg/dose PO/IV
TID
not to exceed
600 mg/dose
|
AI/AII
|
For children >12
years of age,
600 mg PO/IV BID. Pregnancy
category C
|
Clindamycin
|
600 mg PO/IV TID
|
10–13 mg/kg/dose
PO/IV every
6–8 h, not to
exceed
40 mg/kg/day
|
AIII/AII
|
Pregnancy category
B
|
|
Pneumonia
|
Linezolid
|
600 mg PO/IV BID
|
10 mg/kg/dose PO/IV
TID
not to exceed
600 mg/dose
|
AII
|
For children >12
years of age,
600 mg PO/IV BID.
Pregnancy
category C
|
Clindamycin
|
600 mg PO/IV TID
|
10–13 mg/kg/dose
PO/IV every
6–8 h, not to
exceed
40 mg/kg/day
|
BIII/AII
|
Pregnancy category
B
|
|
Osteomyelitis / Septic
arthritis
|
Linezolid
|
600 mg PO/IV BID
|
10 mg/kg/dose PO/IV
TID
not to exceed
600 mg/dose
|
BII/CIII
|
|
Clindamycin
|
600 mg PO/IV TID
|
10–13 mg/kg/dose
PO/IV every
6–8 h, not to
exceed
40 mg/kg/day
|
BIII/AII
|
||
TMP-SMX and
rifampin
|
3.5–4.0 mg/kg/dose
PO/IV
every 8–12 h
& 600 mg PO QD
|
No Data (ND)
|
BII/ND
|
||
Alternative dosing for osteomyelitis (from Medscape 2018):
Preferred:
|
|
Vancomycin (INTRAVENOUS)
|
15 mg/kg IV q12hr if MIC
|
Linezolid
|
600 mg IV/PO q12hr
|
Alternative based on results of sensitivity testing
and intolerance of vancomycin:
|
|
Trimethoprim-sulfamethoxazole
PLUS
Rifampin
|
4 mg/kg IV q12hr (dose based on trimethoprim component)
600 mg PO q24hr or 300-450 mg PO q12hr
|
Oral therapy
based on results of sensitivity testing:
|
|
Doxycycline
|
100 mg PO q12hr
|
Clindamycin
|
450 mg PO q6hr or 600 mg PO q8hr
|
Trimethoprim-sulfamethoxazole
|
2 DS tablets PO q8-12hr
|
Levofloxacin
PLUS
Rifampin
|
500-750 mg PO daily
600-900 mg PO qd (only if the
isolate is sensitive to both antibiotics)
|
Definitive Prosthetic
Joint Infection Treatment [National Antibiotic
Guideline 2019]
Initial
treatment:
*Vancomycin 15-20 mg/kg (actual body weight)
IV q8-12h; NOT to exceed 2 gm/dose
PLUS
Rifampicin 300-450 mg PO q12h
|
·
Duration: 2-6 weeks (according to
treatment strategy)
·
Followed by an oral combination
therapy according to susceptibility.
·
Rifampicin should be included if
implant is in situ
|
References:
1.
UptoDate:
Methicillin-resistant Staphylococcus
aureus (MRSA) in adults: Treatment of skin and soft tissue infections
2.
UptoDate:
Oral antimicrobial therapy for treatment of skin and soft tissue infections due
to methicillin-resistant Staphylococcus
aureus (MRSA) in adults (table)
3.
Skin
and Soft Tissue Infections - Chahine & Sucher (PSAP 2015). Available from: https://www.accp.com/docs/bookstore/psap/2015B1.SampleChapter.pdf
4.
Practice
Guidelines for the Diagnosis and Management of Skin and Soft Tissue Infections:
2014 Update by the Infectious Diseases Society of America.
5.
Clinical
Practice Guidelines by the Infectious Diseases Society of America for the
Treatment of Methicillin-Resistant Staphylococcus
aureus Infections in Adults and Children, 2011.
6.
Medscape:
Osteomyelitis Organism-Specific Therapy, 2018. Available from: https://emedicine.medscape.com/article/2018345-overview
7.
National
Antibiotic Guideline (Malaysia) 2019
All information accessed on 24.02.2020
