Empirical antimicrobial treatment guidelines - adults

This guideline gives recommendations for common infectious conditions in adults – for children please see the Paediatric antibiotic guidelines on
the trust intranet

Prescribers should be aware of the trust Antimicrobial Prescribing Policy which describes general requirements in relation to antimicrobial
prescribing

Prescribers should adhere to the guidelines where clinically practicable – further advice can be obtained from the duty Consultant Microbiologist as
needed

Antibiotic duration is given as general guidance, and should not be taken as a minimum duration. Antibiotics should be reviewed on a daily basis
and stopped as soon as possible. Some patients may require antibiotic courses to be lengthened if clinical response is slow or suboptimal – the
reason for this must be documented.

The use of broad spectrum spectrum / C.difficile risk antibiotics (the five Cs) should be avoided unless there are clear clinical indications for their
use – ciprofloxacin (and other quinolones), cephalosporins, clindamycin, co-amoxiclav and clarithromycin (and other macrolides)

Use of ultra-broad spectrum antibiotics should be restricted to recommended indications, or where recommended by a Microbiologist –
meropenem (and other carbapenems) and piperacillin-tazobactam.

Antibiotic resistant organisms (e.g. MRSA, ESBL producing E.coli / Klebsiella) may be resistant to the empirical antibiotic choices, so it is essential
that appropriate samples are sent promptly to the Microbiology lab for culture and sensitivity testing, and that the results of these are checked by
the clinical teams caring for the patient.

The intravenous (IV) antibiotic regimens in this guidance are for use in hospital inpatients. For outpatient IV therapy (OPAT), please refer to
ambulatory care protocols or discuss with Consultant Microbiologist prior to discharge.
BONE & JOINT INFECTIONS
INDICATION
1ST LINE
Septic arthritis
No risk factors for atypical
organisms (S.aureus likely):
Flucloxacillin 2g qds IV plus
sodium fucidate 500mg tds PO,
ALTERNATIVE
Penicillin allergy (not
anaphylactic):
Cefuroxime 1.5g tds IV
PLUS
DURATION
Total 4-6 weeks, at
least 2 weeks of initial
IV antibiotic (except for
meningo/gonococcus -
NOTES
Synovial fluid must be aspirated
and samples sent for microscopy
and culture prior to starting
antibiotics. Septic joints should
1
Followed by:
Flucloxacillin 500mg-1g qds po
plus sodium fucidate 500mg
tds PO.
Sodium fucidate 500mg tds
PO
discuss with
Microbiologist)
Severe reactions to betalactams:
Teicoplanin 800mg IV stat
then:
if < 80kg – 400mg IV od
if >80kg - 600mg IV od
PLUS
Sodium fucidate 500mg tds
PO
Risk factors for atypical
organisms (e.g. elderly, recent
abdominal surgery, MRSA risk,
suspected,
meningo/gonococcus, IVDA, ICU
patient) – discuss with Micro
Infection of orthopaedic
prostheses
CENTRAL NERVOUS SYSTEM
INDICATION
1ST LINE
Bacterial meningitis
Cefotaxime 2g qds IV
(covers N.meningitidis,
S.pneumoniae & Haemophilus)
For adults >55yrs without
typical meningococcal rash, or
immunocompromised patient,
consider addition of amoxicillin
2g 4-hourly IV (to cover
Listeria)
be aspirated to dryness as often
as required.
Patient should be referred to an
Orthopaedic Surgeon
Directed antibiotic therapy is
based on the results of culture of
operative samples
For empirical therapy, discuss
with Microbiologist
ALTERNATIVE
If history of severe betalactam allergy:
Chloramphenicol 25mg/kg
qds IV (reduce dose as soon
as clinically indicated)
PLUS
Co-trimoxazole 60120mg/kg/day in 2-4 divided
doses if suspected Listeria
meningitis
DURATION
7 days (meningococcus)
10 days (Haemophilus)
14 days
(pneumococcal)
21 days (Listeria)
NOTES
Acute meningitis is notifiable (to
Local Authority Proper Officers)
under the Health Protection
(Notification) Regulations 2010
Patients with suspected
meningococcal disease must be
isolated for the first 48hrs of
treatment
Continued antibiotics should be
guided by results of CSF and/or
blood culture
2
Patients with probable or
confirmed meningococcal
disease must be given
ciprofloxacin 500mg stat po to
eradicate throat colonisation
Where pneumococcal meningitis
is suspected or possible,
consider to start
dexamethasone 0.15mg/kg qds
for 4 days started with or just
before the first dose of antibiotic
Antibiotic prophylaxis of family
contacts may be indicated if
probable or confirmed
meningococcal disease – discuss
with Health Protection Unit.
Herpes simplex
encephalitis
EYE INFECTIONS
INDICATION
Bacterial conjunctivitis
GENITAL INFECTION
INDICATION
Bacterial vaginosis
Acyclovir 10mg/kg tds IV
(usually 750mg tds IV)
10-21 days
Adequate hydration is required
since dehydration increases risk
of nephrotoxicity
1st LINE
Chloramphenicol 0.5% eye
drops, 2-hourly initially, then 4to 6-hourly as infection
responds
ALTERNATIVE
Neomycin 0.5% eye drops 2hourly initially, then 4- to 6hourly as infection responds
DURATION
Until 48 hours after
resolution
NOTES
Discuss with Ophthalmology if
severe
1ST LINE
Metronidazole 400mg bd for 7
days
OR
ALTERNATIVE
Metronidazole 0.75% vaginal
gel 5g at night for 5 nights
OR
DURATION
See text
NOTES
Oral metronidazole is as
effective as topical therapy, and
cheaper
3
Metronidazole 2g stat
Clindamycin 2% cream 5g at
night for 7 nights
Ceftriaxone 500mg stat IM
PLUS
Doxycycline 100mg bd PO
PLUS
Metronidazole 400mg bd PO
Ofloxacin 400mg bd PO
PLUS
Metronidazole 400mg bd PO
Pelvic sepsis
Pelvic inflammatory
disease (PID)
14 days
(ceftriaxone is a single
dose)
Ceftriaxone may be omitted if
low risk of gonorrhoea
Premature rupture of
membranes / group B
strep prophylaxis
Vaginal candidiasis
Less relapse with 7 day
metronidazole regimen than 2g
stat regimen
Avoid 2g stat regimen if
breastfeeding
Treating partners does not
decrease relapse rate
See section on intra-abdominal
sepsis
Avoid ofloxacin regimen if high
risk of gonococcal PID
Essential to test for gonorrhoea
and Chlamydia (refer to GUM)
Metronidazole may be omitted
from the 1st line regimen if side
effects are not tolerated.
See Maternity Department
protocols
Clotrimazole 500mg pessary or
10% cream STAT
OR
Fluconazole 150mg STAT PO
INTRA-ABDOMINAL SEPSIS
INDICATION
1ST LINE
Acute pancreatitis
In pregnancy:
Avoid oral azole and give
intravaginal treatment for 7
days
Clotrimazole 100mg pessary
at night for 6D
Miconazole 2% cream 5g
intravaginally bd for 7 days
See text
All topical and oral azoles give
75% cure
ALTERNATIVE
DURATION
NOTES
Antibiotic not given as a routine
unless clear clinical evidence of
sepsis
4
Gastro-enteritis / food
poisoning
Intra-abdominal sepsis –
appendicitis
Amoxicillin 1g tds IV
Plus
Gentamicin 5mg/kg IV once
daily
Plus
Metronidazole 500mg tds IV
If renal impairment (eGFR
<60mL/min):
Piperacillin-tazobactam 4.5g
tds IV
If penicillin allergy:
Teicoplanin 800mg IV stat
then 400mg od (if <80kg) or
600mg IV od (if >80kg)
plus
Gentamicin 5mg/kg IV once
daily
Plus
Metronidazole 500mg IV tds
5 days if generalised /
complicated.
24 hours antibiotics
adequate if localised /
simple.
Bacterial gastroenteritis (e.g.
Salmonella / Campylobacter)
generally does not require
antibiotic treatment
Antibiotics should be avoided in
colitis due to E.coli O157 (VTEC)
because of the increased risk of
precipitating haemolytic-uraemic
syndrome
Serum levels must be checked
regularly on all patients
receiving regular gentamicin –
see gentamicin section of
antibiotic guidelines.
MAXIMUM 5 DAYS DURATION
FOR GENTAMICIN. Avoid
repeated gentamicin courses for
the same admission. Discuss
with Microbiologist if >5 days
required.
PO switch option:
Co-amoxiclav 625mg tds PO,
or if penicillin allergic (not
anaphylactic) cefalexin
500mg tds PO plus
metronidazole 400mg tds
PO.
5
Intra-abdominal sepsis –
biliary tract (cholecystitis,
cholangitis)
Co-amoxiclav 1.2g tds IV
Followed by co-amoxiclav
625mg tds PO
If severe:
Piperacillin-tazobactam 4.5g
tds IV
Followed by co-amoxiclav
625mg tds PO
If history of severe allergy to
penicillins, use ciprofloxacin
500mg bd PO plus
metronidazole 400mg tds
PO.
Penicillin allergy:
Cefuroxime 1.5g tds IV
PLUS
Metronidazole 500mg tds IV,
Followed by
Cefalexin 500mg tds PO
Plus
Metronidazole 400mg tds PO
5-7 days for
cholecystitis, 5 days
after relief of
obstruction for
cholangitis
Co-amoxiclav is 6 times more
likely to cause a cholestatic
jaundice than amoxicillin. This
can be dangerous, but full
recovery is the rule.
5 days for
uncomplicated disease.
Serum levels must be checked
regularly on all patient receiving
regular gentamicin – see
gentamicin section of antibiotic
guidelines.
Severe penicillin allergy:
Teicoplanin 800mg IV stat
then 400mg od (if <80kg) or
600mg IV od (if >80kg)
Plus
Ciprofloxacin 400mg bd IV
followed by 500mg bd PO
Plus
Metronidazole 500mg tds IV
followed by 400mg tds PO
Intra-abdominal sepsis diverticulitis
Gentamicin 5mg/kg IV once
daily
Plus
Metronidazole 500mg tds IV
If renal impairment (eGFR
<60mL/min):
Piperacillin-tazobactam 4.5g
tds IV
PO switch option:
Co-amoxiclav 625mg tds PO,
Longer courses may be
required – discuss with
Consultant
Microbiology for choice
MAXIMUM 5 DAYS DURATION
6
or if penicillin allergic (not
anaphylactic) cefalexin
500mg tds PO plus
metronidazole 400mg tds
PO.
of agent
FOR GENTAMICIN. Avoid
repeated gentamicin courses for
the same admission. Discuss
with Microbiologist if >5 days
required.
5 days where there is
adequate source
control (e.g.
drainage/debridement).
Where source control is
not possible (e.g.
abscess, persistent
colonic leak) a longer
duration of antibiotic
will be required.
Serum levels must be checked
regularly on all patients
receiving regular gentamicin –
see gentamicin section of
antibiotic guidelines.
If history of severe allergy to
penicillins, use ciprofloxacin
500mg bd PO plus
metronidazole 400mg tds
PO.
Intra-abdominal sepsis –
peritonitis
Amoxicillin 1g tds IV
Plus
Gentamicin 5mg/kg IV once
daily
Plus
Metronidazole 500mg tds IV
If renal impairment (eGFR
<60mL/min):
Piperacillin-tazobactam 4.5g
tds IV
If penicillin allergy:
Teicoplanin 800mg IV stat
then 400mg od (if <80kg) or
600mg IV od (if >80kg)
plus
Gentamicin 5mg/kg IV once
daily
Plus
Metronidazole 500mg IV tds
PO switch option:
Co-amoxiclav 625mg tds PO,
or if penicillin allergic (not
anaphylactic) cefalexin
500mg tds PO plus
metronidazole 400mg tds
Discuss with
Microbiologist for
antibiotic options
where prolonged
antibiotics are needed .
For discharge
possibilities may be oral
antibiotics or
outpatient IV
antibiotics (OPAT).
MAXIMUM 5 DAYS DURATION
FOR GENTAMICIN. Avoid
repeated gentamicin courses for
the same admission. Discuss
with Microbiologist if >5 days
required.
7
PO.
If history of severe allergy to
penicillins, use ciprofloxacin
500mg bd PO plus
metronidazole 400mg tds
PO.
Liver abscess
Piperacillin-tazobactam 4.5g
tds IV
PLUS
Metronidazole 400mg tds PO
Penicillin allergy:
Teicoplanin 800mg IV stat
then 400mg od (if <80kg) or
2-6 weeks
-Send serum for amoebic
serology
-Send pus for culture and adjust
antibiotic regimen as per
sensitivity results
-Avoid long courses of
metronidazole wherever
possible given risk of toxicity e.g.
peripheral neuropathy
-Discuss antibiotic options with
Microbiologist at the time of
hospital discharge
DURATION
10 days
NOTES
Most cases are self limiting viral
infections which do not need
antibiotics
If patient has had more than 5
days of oral Penicillin V then use
Co-amoxiclav 1.2g IV TDS.
If patient has infectious
mononucleosis (glandular fever)
and >5 d oral Penicillin V use
Cefuroxime 750mg IV TDS and
600mg IV od (if >80kg)
plus
Ciprofloxacin 500mg BD PO
plus
Metronidazole 400mg tds PO
RESPIRATORY TRACT – UPPER
INDICATION
1ST LINE
Bacterial tonsillitis /
Penicillin V 500mg qds PO
pharyngitis
Severe Tonsillitis
Benzyl Penicillin 1.2 g qds IV
PLUS
Metronidazole 400mg tds PO
(500mg IV TDS if unable to
swallow)
ALTERNATIVE
Penicillin allergy:
Clarithromycin 250-500mg
bd PO
Clarithromycin 500mg IV BD
PLUS
Metronidazole 400mg PO
TDS (500mg IV TDS if unable
to swallow)
10 days
(switch to PO when
possible)
8
Acute otitis media
Amoxicillin 500mg tds PO
Penicillin allergy:
Clarithromycin 250-500mg
bd PO
5 days
Malignant otitis externa
Piperacillin/ tazobactam 4.5g
tds IV
Consult microbiologist
Acute Parotitis
Co-amoxiclav 1.2g tds IV
Acute Mastoiditis
Co-amoxiclav 1.2g tds IV
Clarithromycin 500mg bd IV
PLUS
Metronidazole 400mg tds PO
(500mg tds IV if unable to
take PO)
Cefuroxime 1.5g tds IV
PLUS
Metronidazole 400mg tds
PO (500mg tds IV if unable to
take PO)
Prolonged IV may be
required – Consult
microbiologist
7 days
If severe type 1
hypersensitivity
(anaphylaxis):
Teicoplanin 400mg od IV
PLUS
Ciprofloxacin 500mg bd PO
PLUS
Metronidazole (as above).
7 days
Metronidazole 500mg IV TDS
OM resolves in 24h in 60%
without antibiotics and does not
prevent deafness.
Consider 2 or 3 day delayed
antibiotics.
Immediate antibiotics indicated
if otorrhoea.
Review microbiology results
IV Clarithromycin - risk of
phlebitis. Switch to PO as soon
as possible
Consider PO switch ASAP
Switch Co-amoxiclav 1.2g IV to
625mg tds PO
If penicillin allergy:
Switch Cefuroxime 1.5g IV +
Metronidazole 500mg IV to
Cefalexin 500mg tds PO and
Metronidazole 400mg tds PO
If severe type 1
hypersensitivity(anaphylaxis):
Teicoplanin 400mg IV - no PO
equivalent (consult microbiologist)
PLUS
Ciprofloxacin 400mg bd PO
PLUS
9
Metronidazole 400mg tds PO
Acute rhinosinusitis
7 days
Consider delayed 7 day
antibiotics
Immediate antibiotics if purulent
nasal discharge
Consider Azithromycin or
Doxycycline in patients not
tolerating / allergic to
Clarithromycin.
Up to 8 weeks
Recommended as per EPOS2012
(European Position Paper on
Rhinosinusitis)
Benzyl Penicillin 1.2 g qds IV
PLUS
Metronidazole 400mg tds PO
(500mg IV TDS if unable to
swallow)
Clarithromycin 500mg bd IV
PLUS
Metronidazole 400mg tds
PO (500mg tds IV if unable to
take PO)
10 days
If patient has had a course of
oral Penicillin V then use
Cefuroxime 750mg tds IV
PLUS
Metronidazole 500mg tds IV
Cefuroxime 1.5g tds IV
PLUS
Metronidazole 400mg tds PO
(500mg tds IV if unable to
swallow)
Consult microbiologist only if
type 1 anaphylaxis
7-10 days
ALTERNATIVE
Or, if penicillin allergy:
Doxycycline 100mg bd PO
DURATION
5 days
Amoxicillin 500mg tds PO
Doxycycline 100mg bd PO
(double dose if severe)
If persistent infection:
use agent to cover anaerobes
- Co-amoxiclav 625mg tds PO
OR
add Metronidazole 400mg
tds PO to Doxycycline
Chronic rhinosinusitis
Clarithromycin 500mg bd PO
for 2 weeks followed by
Clarithromycin 250mg bd PO
for up to 8weeks
Peritonsillar abscess
(Quinsy)
Supraglottitis
RESPIRATORY TRACT - LOWER
INDICATION
1ST LINE
Acute bronchitis
Usually none, but if severe:
Amoxicillin 500mg tds PO
NOTES
Predominantly viral – antibiotics
usually not required in
previously healthy adults
10
Acute exacerbation of
COPD
Amoxicillin 500mg tds PO
(1g tds IV for first 48hrs if
severe)
Doxycycline 100mg bd PO
If severe, or no response to 1st
line:
Co-amoxiclav 1.2g tds IV for
48hrs, then 625mg tds PO
OR
If penicillin allergy (not
anaphylactic) and severe, or
no response to 1st line:
Cefuroxime 1.5g tds IV for
48hrs, followed by Cefalexin
500mg tds PO to complete 5
days
If severe reaction to betalactams:
Clarithromycin 500mg bd PO
(500mg bd IV for first 48hrs if
severe)
5 days
Community acquired
pneumonia (CAP) – mild
CURB-65 score <1
Amoxicillin 500mg – 1g tds PO
Doxycycline 100mg bd PO
OR
Clarithromycin 500mg bd PO
5-7 days
Community acquired
pneumonia (CAP) moderate
CURB-65 score >2
Benzylpenicillin 1.2g qds IV
initially, then amoxicillin
500mg-1g tds po
PLUS
Clarithromycin 500mg bd po
(IV for first 48hrs if required)
Switch from IV to PO antibiotic
at 48hrs if improving
If penicillin allergy:
Doxycycline 100mg bd PO
7 days
If risk factors for resistant
organisms, see section
below.
If penicillin allergy and unable
to take oral medication:
Teicoplanin 800mg IV stat
then:
if < 80kg – 400mg IV od
if >80kg - 600mg IV od
PLUS
COPD exacerbations are often
caused by viruses, but bacterial
infection may co-exist.
Antibiotics are indicated if:
 Increased volume of
sputum
 Increased purulence of
sputum
 Increased shortness of
breath
IV antibiotics should be
converted to oral equivalents
once fever has resolved (usually
within 48hrs).
Do not give a macrolide (e.g.
clarithromycin) as a matter of
routine unless evidence of
pulmonary infiltrates on CXR or
patient is allergic to penicillin.
CAP should have evidence of
consolidation on CXR
Use CURB-65 score for severity
assessment, score must be
documented.
Assign one point to each of the
following:
-Mental Confusion
-Urea >7mmol/L (disregard if
pre-existing)
-Respiratory rate >30/min
11
Clarithromycin 500mg bd IV
Followed by switch to PO
doxycycline after 48hrs
-Blood pressure systolic
<90mmHg or diastolic <60mmHg
-Age >65yrs
If severe (anaphylactic)
penicillin allergy and unable
to take oral medications:
Teicoplanin 800mg IV stat
then:
if < 80kg – 400mg IV od
if >80kg - 600mg IV od
PLUS
Levofloxacin 500mg bd IV
Followed by switch to PO
doxycycline after 48hrs
Community acquired
pneumonia (CAP)
in patients with risk factors
for resistant organisms, or if
recommended by Consultant
Chest Physician or
Microbiologist:
Risk factors:
- admission to ICU
- hospitalised with 14 days
- significantly
immunocompromised:
-
HIV infection
>10mg/day
prednisolone
other
immunosuppressive
agents
Co-amoxiclav 1.2g tds IV
initially, then Co-amoxiclav
625mg tds PO
PLUS
Clarithromycin 500mg bd IV,
followed by Clarithromycin
500mg bd PO
If penicillin allergy:
Cefuroxime 1.5g tds IV
PLUS
Clarithromycin 500mg bd IV,
followed by a switch to
Doxycycline 100mg bd PO
If severe (anaphylactic)
penicillin allergy:
Teicoplanin 800mg IV stat
then:
if < 80kg – 400mg IV od
if >80kg - 600mg IV od
PLUS
Levofloxacin 500mg bd IV
When clinically resolving
switch to Doxycycline 100mg
bd PO
Up to 3 weeks antibiotic
treatment may be required if
atypical cause suspected or
confirmed (e.g. Legionnaires’
disease)
CURB-65 score >3 = severe CAP.
Requires hospital admission.
Send urine for Legionella and
pneumococcal antigen.
7 days
If condition of mild/moderate
CAP worsens after 48hrs of
antibiotic therapy, treat as sever
CAP.
If MRSA colonised, consider
addition of teicoplanin.
Narrow spectrum antibiotic
therapy (e.g. benzylpenicillin +
clarithromycin) is validated in
patients who do not have risk
factors for resistant organisms
(Charles PG et al, Clin Infect Dis
2008; 46:1512-21)
12
-
-
active treatment for
cancer
prior organ
transplantation
Primary atypical
pneumonia
Clarithromycin 500mg bd
IV/PO
Switch from IV to PO at 48hrs if
improving
Legionnaires’ disease:
In addition to clarithromycin,
add Rifampicin 300-600mg
bd PO
Psittacosis:
Use a tetracycline e.g.
Doxycycline 100mg bd PO
14 days, may require up
to 21 days
Send urine for antigen testing
where Legionella suspected
Mycoplasma can be detected by
sending nose/throat viral swabs
for respiratory PCR
Psittacosis – diagnosis is by
serology – discuss with
Microbiologist where suspected
Aspiration pneumonia
Amoxicillin 500mg tds PO (IV
500mg-1g tds IV for first 48hrs
if required)
PLUS
Metronidazole 500mg IV /
400mg PO tds
If penicillin allergy:
Doxycycline 100mg bd PO
PLUS
Metronidazole 500mg IV /
400mg PO tds
If unable to take PO
medication, replace
doxycycline with
Teicoplanin 800mg IV stat
then:
if < 80kg – 400mg IV od
if >80kg - 600mg IV od
5-7 days
Routine antibiotic treatment is
not required for aspiration
unless there is persistence of
chest signs or fever for 48hrs
post aspiration.
Community acquired
pneumonia (CAP) in
patients with influenza like
illness (influenza season)
Treat for CAP as above. If
treated with Benzylpenicillin or
Amoxicillin, add Flucloxacillin
500mg-1g qds IV
Penicillin allergy:
Treat as above for CAP
Treat influenza with oseltamivir /
zanamivir
Additional flucloxacillin not
required for patients receiving
co-amoxiclav, cefuroxime or
13
Hospital acquired LRTI
without pneumonia
Doxycycline 100mg bd PO
If failed recent course of
doxycycline:
Co-amoxiclav 625mg tds PO
5 days
Hospital acquired
pneumonia (HAP) – nonsevere
Doxycycline 100mg bd PO
If severe (anaphylactic)
penicillin allergy:
5-7 days
If contraindication to
doxycycline or unresponsive to
doxycycline:
Co-amoxiclav 625mg tds PO
(1.2g tds IV for first 48hrs if
required),
Or if penicillin allergy:
Cefuroxime 1.5g tds IV (add
metronidazole if aspiration
suspected)
Levofloxacin 500mg bd IV/PO
Add Metronidazole if
suspected aspiration.
Diagnosis of HAP:
New or progressive infiltrate +
clinical characteristics plus at
least one of:
-Fever >38oC
-Leucocytosis or leucopenia
-Purulent secretions
If unresponsive after 48hrs
treatment, treat as severe
HAP
If unresponsive after 48hrs
treatment, treat as severe HAP
Hospital acquired
pneumonia (HAP) – severe
(not Pseudomonas, not
ventilated)
Amoxicillin 1g IV tds plus
Temocillin 2g IV bd
Replace Amoxicillin with
Teicoplanin or Vancomycin if
known MRSA colonised
Add Flucloxacillin if methicillin-
If penicillin allergy (not
severe):
Meropenem 500mg tds IV
(1g tds IV if ICU).
Add Teicoplanin or
Vancomycin if known MRSA
colonised
teicoplanin.
Not indicated in the absence of
purulent / mucopurulent
sputum. Of most benefit if
patient has increased dyspnoea
and increased purulent sputum.
Hospital acquired pneumonia is
defined as pneumonia that
occurs 48 hours or longer after
admission or admission within
the last 7 days.
7 days
(10-14 days if S.aureus)
Routine antibiotic treatment is
not required for aspiration
unless there is persistence of
chest signs or fever for 48hrs
post aspiration.
-Temocillin is not active vs
Pseudomonas or staphylococci –
add additional antibiotic as
suggested if colonised with these
-There are no UK guidelines to
assess severity of HAP, but the
following criteria, in addition to
the HAP features above, would
14
sensitive (MSSA) colonised
Add Clarithromycin if
suspected atypical pneumonia
Add Metronidazole if
suspected aspiration
Hospital acquired
pneumonia (HAP) –
ventilator associated
pneumonia or colonised
with Pseudomonas
SOFT TISSUE INFECTION
INDICATION
Animal or human bite
Piperacillin-tazobactam 4.5g
tds IV
Add Teicoplanin or
Vancomycin if known MRSA
colonised
Add Clarithromycin if
suspected atypical pneumonia
1ST LINE
Co-amoxiclav 625mg tds PO
suggest severe pneumonia:
 New mental confusion
 Respiratory rate 30/min
or more
 Hypoxia (PaO2 <8kPa or
SaO2 <92% on any FiO2)
 Bilateral or multilobular
chest XRay shadowing
 Blood pressure systolic
BP <90mmHg or diastolic
<60mmHg
Add Clarithromycin if
suspected atypical
pneumonia
If severe penicillin allergy:
Teicoplanin 800mg IV stat
then:
if < 80kg – 400mg IV od
if >80kg - 600mg IV od
PLUS
Ciprofloxacin 400mg bd IV
Add Metronidazole if
suspected aspiration
Teicoplanin 800mg IV stat
then:
if < 80kg – 400mg IV od
if >80kg - 600mg IV od
PLUS
Ciprofloxacin 400mg bd IV
ALTERNATIVE
Penicillin allergic:
Doxycycline 100mg bd PO
PLUS
Metronidazole 400mg tds PO
7 days
(10-14 days if S.aureus
or P.aeruginosa)
DURATION
7 days
NOTES
Prophylactic course may be
shorter (5 days)
Alternative options for penicillin
allergy are less effective and
patient progress should be
reviewed
If human bite, assess risk fo
blood borne viruses (hepatitis B
& C, HIV)
15
If animal bite abroad, assess risk
of rabies
Cellulitis of limb – mild
(No signs of systemic
toxicity & no uncontrolled
co-morbidities)
Flucloxacillin 500mg qds PO
Penicillin allergic:
Clarithromycin 500mg bd PO
7 days
Cellulitis of limb –
moderate / severe
(Sepsis syndrome or
complicating comorbidities)
Benzylpenicillin 1.2g qds IV
PLUS
Flucloxacillin 1g qds IV,
Penicillin allergic / MRSA
colonised:
Teicoplanin 800mg IV stat
then:
if < 80kg – 400mg IV od
if >80kg - 600mg IV od
7-10 days
Diabetic foot – infection of
soft tissue / cellulitis
without ulceration
Diabetic foot ulcer
When clinically improving
switch to flucloxacillin 500mg
qds PO
Non severe:
Flucloxacillin 500mg qds PO
Severe:
Flucloxacillin 2g qds IV then to
flucloxacillin 500mg qds PO
when clinically improving
Non-severe:
Co-amoxiclav 1.2g tds IV, then
to co-amoxiclav 625mg tds PO
Severe:
(Systemic signs, in limb
threatening infection, or
otherwise judged severe)
Piperacillin-tazobactam 4.5g
If exposure to fresh water at
site of skin break:
Add Ciprofloxacin 750mg bd
PO
Penicillin allergic:
Clindamycin 450mg qds PO
Non-severe / penicillin
allergic:
Clindamycin 450mg qds PO
PLUS
Ciprofloxacin 500mg bd PO
(avoid ciprofloxacin if MRSA
carrier – seek advice from
Microbiology)
Review for suitability for
outpatient IV therapy:
 Ceftriaxone 2g IV once
daily
 Teicoplanin IV if MRSA
colonised
Draw demarcation line to follow
progress
Swab wound if broken skin
Check for previous MRSA result
7-10 days
7-14 days
Add teicoplanin if MRSA
colonised
Severe / penicillin allergic:
16
tds IV
Add teicoplanin if MRSA
colonised.
Diabetic foot infection osteomyelitis
Flucloxacillin 500mg qds PO
PLUS
Sodium fusidate 500mg tds PO
Neck abscess
Co-amoxiclav 1.2g IV TDS
Necrotising fasciitis /
Fournier’s gangrene
Piperacillin – tazobactam 4.5g
tds IV
PLUS
Teicoplanin 800mg IV stat
then:
if < 80kg – 400mg IV od
if >80kg - 600mg IV od
PLUS
Gentamicin 5mg/kg once
daily (see gentamicin section,
needs drug level checked)
PLUS
Metronidazole 500mg tds IV
or 400mg tds PO
Clindamycin 450mg tds PO
6 weeks
If no improvement after 4-6
weeks (XRay):
Switch to Ciprofloxacin
500mg bd PO to cover
pseudomonas.
If MRSA infection:
Rifampicin 300mg bd PO
PLUS
Doxycycline 200mg stat, then
100mg once daily PO
(if MRSA isolate is
susceptible)
Clarithromycin 500mg bd IV
PLUS
Metronidazole 400mg tds
PO (500mg tds IV if unable
to take PO)
If penicillin allergic:
Teicoplanin 800mg IV stat
then:
Suspected if red, swollen,
sometimes painful joint or toe in
the presence of nearby infected
ulcer
Underlying bone is usually
exposed
XRay may be normal in early
stages
If initial XRay is negative and
osteomyelitis is suspected, an
MRI should be performed (NICE
CG 119: Inpatient management
of diabetic foot problems, Feb
2012)
7 days
Depends on clinical
response
Prompt assessment by surgeons
is essential re debridement
17
Gentamicin 5mg/kg once daily
(see Gentamicin section –
needs monitoring of drug
levels)
if < 80kg – 400mg IV od
if >80kg - 600mg IV od
PLUS
Gentamicin 5mg/kg once
daily
(see Gentamicin section –
needs monitoring of drug
levels)
PLUS
Metronidazole 500mg tds IV
or 400mg tds PO
Clarithromycin 500mg bd PO
7 days
Discuss with ophthalmology
Pre-septal cellulitis (around
eye) - mild
Pinna/Facial Cellulitis
(superficial skin / soft
tissue)
Co-amoxiclav 625mg tds PO
Flucloxacillin 1g qds IV
PLUS
BenzylPenicillin 1.2g qds IV
Clarithromycin 500mg bd IV
7 days
IV Clarithromycin - risk of
phlebitis. Switch to PO as soon
as possible
Facial cellulitis –
odontogenic and other
deep soft tissue infections
Co-amoxiclav 1.2g tds IV
Cefuroxime 1.5g tds IV
PLUS
Metronidazole 400mg tds PO
(500mg tds IV if unable to
take PO)
7 days
Gentamicin – risks of
nephrotoxicity and ototoxicity
Gentamicin duration should be
kept <5 days wherever possible
– review results of cultures and
switch antibiotics according to
sensitivities
If severe type 1
hypersensitivity
(anaphylaxis):
In renal impairment (eGFR
<60ml/min), Gentamicin can be
replaced with Ciprofloxacin
400mg bd IV (500mg bd PO if
able to take oral medications)
Teicoplanin 400mg od IV
PLUS
Gentamicin 5mg/kg/day plus
Metronidazole
(as above).
Severe pre-septal cellulitis
Co-amoxiclav 1.2g IV TDS
Cefuroxime 1.5g tds IV
PLUS
7 – 10 days
Gentamicin – risks of
18
Metronidazole 400mg tds PO
(500mg tds IV if unable to
take PO)
and ALL orbital cellulitis
nephrotoxicity and ototoxicity
Gentamicin duration should be
kept <5 days wherever possible
– review results of cultures and
switch antibiotics according to
sensitivities
If severe type 1
hypersensitivity
(anaphylaxis):
Teicoplanin 400mg od IV
PLUS
Gentamicin 5mg/kg/day
PLUS
Metronidazole (as above).
SYSTEMIC SEPSIS
INDICATION
Sepsis – source unclear
1ST LINE
Amoxicillin 1g tds IV
PLUS
Gentamicin 5mg/kg stat
(review need for further doses,
if continuing drug levels will
need to be monitored – see
Gentamicin section)
Review clinical progress –
change antibiotic to regimen as
determined by likely source –
see relevant sections.
ALTERNATIVE
If penicillin allergy:
Cefuroxime 1.5g tds IV
PLUS
Gentamicin 5mg/kg stat
(review need for further
doses, if continuing drug
levels will need to be
monitored – see Gentamicin
section)
If severe penicillin allergy
(type 1 immediate reaction):
Teicoplanin 400mg 12-hourly
IV for 3 doses, then 400mg
once daily
PLUS
Ciprofloxacin 400mg bd IV
(750mg bd PO if able to take
In renal impairment (eGFR
<60ml/min), Gentamicin can be
replaced with Ciprofloxacin
400mg IV BD (500mg BD PO if
able to take oral medications)
DURATION
48hrs in the first
instance, subsequent
antibiotic choice and
duration depends on
the source of infection
– refer to relevant
sections of the
empirical guidelines.
NOTES
Definition of sepsis:
The systemic inflammatory
response syndrome (SIRS) plus
clinical evidence of infection.
SIRS is defined by 2 or more of:
 Temp <36°C or >38°C
 Heart rate >90 beats/min
 Respiratory rate >20
breaths/min
 WBC count <4 or >12 x 109/L
Initial regimen for sepsis (not
severe sepsis) of unknown
source, where a chest or urinary
infection is thought most likely.
Results of recent microbiology
samples (e.g. urine and sputum)
19
oral medications)
PLUS
Gentamcin 5mg/kg stat
(review need for further
doses, if continuing drug
levels will need to be
monitored – see Gentamcin
section)
Severe sepsis
Piperacillin-tazobactam 4.5g
tds IV
PLUS
Gentamicin 5mg/kg stat
(review need for further doses,
if continuing drug levels will
need to be monitored – see
Gentamicin section)
Penicillin allergy (not
anaphylactic) or recent ESBL:
Meropenem 1g tds IV
If MRSA colonised:
Add Vancomycin or
Teicoplanin (see relevant
sections for advice on dosing
and monitoring)
If severe penicillin allergy:
Teicoplanin 800mg IV stat
then:
if < 80kg – 400mg IV od
if >80kg - 600mg IV od
PLUS
Ciprofloxacin 400mg bd IV
(750mg bd PO if able to take
oral medications)
PLUS
Gentamicin 5mg/kg stat
(review need for further
doses, if continuing drug
levels will need to be
monitored – se Gentamicin
section)
must be reviewed if available as
this may direct a broader
regimen.
Antibiotic regimen should be
changed to that appropriate to
likely source after clinical review.
7-10 days
Severe sepsis is sepsis plus
evidence of organ dysfunction
Definition of sepsis:
The systemic inflammatory
response syndrome (SIRS) plus
clinical evidence of infection.
SIRS is defined by 2 or more of:
 Temp <36°C or >38°C
 Heart rate >90 beats/min
 Respiratory rate >20
breaths/min
 WBC count <4 or >12 x 109/L
Organ dysfunction is defined as
sepsis plus any of the following:
 Systolic BP <90mmHg
 Oliguria
(output<0.5ml/kg/hr)
 Hypoxaemia (SpO2<95% on
>60% O2)
 Altered mental status
 Lactate >4mmol/L
20
 EWS >5
Septic shock is defined as severe
sepsis with refractory arterial
hypotension or hypoperfusion
abnormalities in spite of
adequate fluid resuscitation.
Neutropenic fever
Piperacillin-tazobactam 4.5g
qds IV
PLUS
Gentamicin 5mg/kg once daily
(drug levels should be
monitored, see Gentamcin
section)
If penicillin allergic:
Teicoplanin 800mg IV stat
then:
if < 80kg – 400mg IV od
if >80kg - 600mg IV od
PLUS
Ciprofloxacin 750mg bd PO
PLUS
Gentamicin 5mg/kg once
daily IV
(drug levels should be
monitored, see Gentamcin
section)
Dependent on clinical
response.
Definition of neutropenic sepsis:
Discuss with
Microbiology
Three sets of blood cultures
must be taken prior to
Neutrophil count 0.5 x 109 per
litre or lower
PLUS, either:
temperature >38°C
Or other signs and symptoms
2nd line regimen
(unresponsive to 1st line):
Teicoplanin 800mg IV stat
then:
if < 80kg – 400mg IV od
if >80kg - 600mg IV od
PLUS
Meropenem 1g tds IV
Endocarditis Acute onset, IVDU, MRSA
Vancomycin (see vancomycin
section for dosing)
21
colonised, or prosthetic
valve
Endocarditis –
Indolent (subacute)
presentation and native
valve
PLUS
Gentamicin 1mg/kg bd (see
gentamcin section – need drug
levels)
PLUS
Rifampicin 300 - 600mg bd PO
if prosthetic valve
Amoxicillin 2g 4-hourly IV
PLUS
Gentamicin 1mg/kg bd IV (see
gentamcin section – need drug
levels)
Line infection – peripheral
cannula infection (nonsepsis)
Flucloxacillin 500mg qds PO
(only if MRSA screen is
negative)
Line infection - central /
tunnelled line sepsis and
peripheral cannula
infection with sepsis
IV Vancomycin (see
vancomycin section for dosing)
commencing antibiotics
Definitive antibiotic therapy is
directed by culture and
sensitivity – discuss with
Microbiologist
Penicillin allergic:
Vancomycin IV (see
vancomycin section for
dosing)
PLUS
Gentamcin 1mg/kg tds IV
(see gentamcin section –
need drug levels)
If penicillin allergic or MRSA
positive:
Doxycycline 100mg bd PO
(most MRSA isolates are
doxycycline sensitive, but if
not, manage as below)
Three sets of blood cultures
must be taken prior to
commencing antibiotics – at
least 6 hours apart where
possible.
Definitive antibiotic therapy is
directed by culture and
sensitivity – discuss with
Microbiologist
7 days
NOT in patients with features of
systemic sepsis
Consider antibiotic therapy
where VIP score 3-4
MRSA screening swab status
must be checked
7 days
Central / tunnelled lines
generally require removal –
discuss with Microbiology as
appropriate
For central / tunnelled line
sepsis, collect central and
peripheral blood cultures prior
to starting antibiotics
If associated
bacteraemia, follow
Microbiology advice for
regimen / duration
22
Consider adding a stat dose of
gentamicin if risk factors for
gram negative infection
For peripheral cannula infection
– commence if VIP score 5
URINARY TRACT INFECTION
INDICATION
1ST LINE
Lower UTI
Nitrofurantoin 50mg qds PO
(avoid if eGFR <40ml/min)
OR
Trimethoprim 200mg bd PO
(avoid if eGFR <30ml/min
Complex UTI –
Gentamicin 5mg/kg once daily
Failure of either 1st line
IV for 2 doses then review
treatments, recent
culture results.
urological surgery,
structural abnormalities of If eGFR <60mL/min, take
urinary tract, oral route
trough level 20 hours post 1st
unviable
dose and await result – only redose when level <1mg/L
In moderate/severe renal
impairment, consider
Temocillin as alternative if not
penicillin allergic (see dosing
opposite)
ALTERNATIVE
If resistant to 1st line / renal
failure / other contraindication (e.g. pregnant):
Cefalexin 500mg bd PO
DURATION
Female: 3 days
Male: 5-7 days
If gentamicin resistant
ESBL/ampC E.coli or
Klebsiella from a recent urine
sample:
Temocillin 2g bd IV
2 days Gentamicin,
followed by 5 days of
antibiotic as directed by
urine sensitivity
If penicillin allergic AND
gentamicin resistant
ESBL/ampC E.coli or Klebsiella
from a recent urine sample:
Meropenem 500mg tds IV
If not penicillin allergic but
with impaired renal function:
If eGFR 30-60mL/min:
Temocillin 1g bd IV
If eGFR 10-30mL/min:
Temocillin 1g once daily IV
7 days for Temocillin /
Meropenem
NOTES
Send urine for culture and
sensitivity before starting
antibiotics
-Review results at 48hours,
consider IV to oral switch or
cessation of antibiotics
-De-escalate where possible to
narrow spectrum antibiotic
-Bacteriuria (or positive dipstick)
in the absence of clinical signs
and symptoms of UTI does not
warrant antibiotic treatment
(unless in known risk group)
-Catheter related bacteriuria
does not require treatment
unless clinical evidence of
infection
-Temocillin is not active vs
Pseudomonas & gram positive
organisms – use other agents for
these
23
If eGFR 10mL/min:
Temocillin 500mg once daily
IV
Pyelonephritis
Co-amoxiclav 1.2g tds IV
Add gentamicin 5mg/kg stat if
severe
(review need for further doses,
if continuing drug levels will
need to be monitored – see
Gentamcin section)
Followed by: Co-amoxiclav
625mg tds PO
Penicillin allergic:
Ciprofloxacin 750mg bd PO
(400mg bd IV if unable to
take oral medications)
OR
Gentamicin 5mg/kg once
daily
(see gentamcin section –
need drug levels)
7-10 days (if coamoxiclav),
7 days if ciprofloxacin
or gentamicin
-The following patients are at
risk of ESBL/ampC producing
E.coli / Klebsiella:
 >65 yrs of age
 long term catheter in
situ
 recent urological
procedure
 ESBL/ampC +ve E.coli or
Klebsiella in the previous
24 months
Pyelonephritis defined as:
Renal angle tenderness plus
presence of two SIRS criteria:
 Temp <36°C or >38°C
 Heart rate >90
beats/min
 Respiratory rate >20
breaths/min
 WBC count <4 or >12 x
109/L
If eGFR <20mL/min discuss
antibiotic choice with
Microbiology.
24