Transcript Antibiotic Guidelines

Antibiotic prescribing
at NSMC
Sue Neal / Steve Newell
16/5/03
Plan for the meetings:
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Enough material for 2 meetings
Consider some research
Look at antibiotic prescribing at
NSMC
For respiratory illnesses
For UTI in children
What are the problems?
Do antibiotics work?
– EBM to support their use?
– For what conditions?
 Huge amounts of time used
 Huge costs involved
 Prescribing legitimises consultation
 Help-seeking behaviour reinforced
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Antibiotic Guidelines
An examination of antibiotic
prescribing with reference to
new guidelines and minor
ailments
Conditions
Acute Sinusitis
 Sore Throat
 Otitis Media
 Cough
 LRTI
 UTI
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Sources
Antimicrobial Prescribing
Guidance for Primary Care
 SMAC
 Clinical Evidence
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Acute Sinusitis – the
evidence base
Antibiotics may be effective in
PROVEN acute sinusitis
 The adult with ‘sinusitis – like
symptoms’ in primary care does not
need immediate antibiotics
 Any effects may be minimal/modest
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The guidelines say
Many cases are viral
 Reserve Rx for severe
illness/persistant symptoms
 Penicillin V 500mg QDS 3-7 days or
 Erythromycin 250 QDS
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Primary-care-based randomised placebo-controlled trial of
antibiotic treatment in acute maxillary sinusitis.
Lancet. 1997 May 17;349(9063):1476
van Buchem FL, Knottnerus JA, Schrijnemaekers VJ, Peeters MF
BACKGROUND: The value of antibiotics in acute rhinosinusitis is
uncertain. Although maxillary sinusitis is commonly diagnosed and
treated in general practice, no effectiveness studies have been done
on unselected primary-care patients. We used a randomised,
placebo-controlled design to test the hypothesis that there would be
an improvement associated with amoxicillin treatment for acute
maxillary sinusitis patients presenting to general practice.
METHODS: Adult patients with suspected acute maxillary sinusitis
were referred by general practitioners for radiographs of the
maxillary sinus. Those with radiographic abnormalities (n = 214)
were randomly assigned treatment with amoxicillin (750 mg three
times daily for 7 days; n = 108) or placebo (n = 106). Clinical course
was assessed after 1 week and 2 weeks, and reported relapses and
complications were recorded during the following year.
FINDINGS: After 2 weeks, symptoms had improved substantially or
disappeared in 83% of patients in the study group and 77% of
patients taking placebo. Amoxycillin did not influence the clinical
course of maxillary sinusitis nor the frequency of relapses during
the 1-year follow-up. Radiographs had no prognostic value, nor
were they an effect modifier. Side-effects were recorded in 28% of
patients given amoxycillin and in 9% of those taking placebo (p <
0.01). The occurrence of relapses was similar in both groups (21
vs 17%) during the follow-up year.
INTERPRETATION: Antibiotic treatment did not improve the clinical
course of acute maxillary sinusitis presenting to general practice.
For these patients, an initial radiographic examination is not
necessary and initial management can be limited to symptomatic
treatment. Whether antibiotics are necessary in more severe cases
warrants further study.
Practice at NSMC
58 cases of acute sinusitis
examined across all clinicians
 Symptoms
 Prescribing
 Other Rx
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Findings
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Wide variety in prevalence indicating
diagnostic variability
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Symptoms - 4 = no history
- 12 post URTI
- 22 pain
- 23 tenderness
- congestion / discharge
/ fever
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Duration
- 33 had a comment
regarding duration
- less than 1 week = 8
- 2 weeks to 1 year
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Prescribing - 100% (1 deferred, 1 nasal spray)
- Amoxicillin / Ampicillin /
Erythromycin
- Trimethoprim & Doxycycline
For - 3 days
- 5 days
- 7 days ( 35)
- 10 days
- Other regimes
Questions
What syndrome are we treating?
 Are the treatments evidence
based?
 Do we need to make any changes
to treatments?
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Other treatments
Steaming
 Nasal sprays
 Analgesia
 5 went onto second ABX
courses, X-ray or referral
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Sore throat – the evidence base
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Most sore throats are viral and selflimiting
Strep is isolated in 30% of sore throats
BUT
Asymptomatic carriage can be as high as
40%
Typical features only present in 15% of
patients with strep throat
Recent studies do not support antibiotics
as preventative of non-suppurative
complications which are rare anyway
The guidelines say
- indications to treat
Severely inflamed throat AND
marked systemic upset
 Conformed strep infection
 Scarlet fever
 Impaired immunity
 PH non-suppurative complications
 Evidence of obstruction with ENT
referral
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With
Penicillin V 500mg QDS for 7 –10
days
 Erythromycin if allergic 250 QDS
 Deferred script to use if no better 3
days
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Otitis Media – the evidence base
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Approx 80% of acute OM resolves in 3
days without Rx
 ABX do not influence subsequent OM or
deafness at 1 month
 May reduce no of children still in pain 2-7
days but for each 1 improved 3 will
develop ABX related side effects
 Repeated courses may make recurrent
infection more likely
UTI in children
BMJ 1996;312:961-964 (13 April)
Education and debate: ABC of Urology:
URINARY INCONTINENCE AND URINARY
INFECTION
Chris Dawson, Hugh Whitfield
Urinary tract infection: Management in children
Collecting urine specimens to confirm the diagnosis of
urinary tract infection is [..] difficult in children. A
midstream sample can be collected from older children,
but in younger children a sterile bag placed over the
genitalia to catch the urine may be needed. Suprapubic
aspiration of the bladder is seldom required.
..1% of boys aged under 11 years develop a urine
infection, but the incidence is three times as high in girls.
Most such infections occur in the first 12 months of life.
The greatest danger in such children is the development
of upper tract infection and subsequent renal scarring.
Vesicoureteric reflux accompanies urinary tract infection
in children in 20-50% of cases. Although reflux may be the
cause of infection, episodes of infection may lead to
transient reflux. Vesicoureteric reflux alone is not
sufficient to cause renal cortical scarring - infection must
also be present
Treating uncomplicated infections for 3-5 days with
antibiotics usually suffices.
All children with a urinary infection should be
Investigated:
An ultrasound scan or intravenous urogram will show
abnormalities of the upper tracts.
A voiding cystourethrogram should be performed to
look for bladder outlet obstruction or vesicoureteric
reflux.
Sexual abuse as a cause of urinary infection in children
should not be forgotten.
Repeated infections should be treated accordingly:
Prophylactic antibiotics may be needed if more than
three infections occur during six months.
Preventive measures [..] include adequate fluid intake
and the avoidance of constipation.
If vesicoureteric reflux is discovered then conservative
management is appropriate initially. Higher grades of
reflux are unlikely to settle spontaneously, but lower
grade reflux – i.e. not reaching the renal pelvis – may
settle without intervention. Surgery is likely to be needed
if repeated infections occur while the child is taking
prophylactic antibiotics, if antibiotic compliance is low, or
if reflux persists after lengthy surveillance.
BMJ 1999;319:1173-1175 ( 30 October )
Clinical review: Clinical evidence
Urinary tract infection in children
James Larcombe, general practitioner.
Sedgefield, County Durham TS21 3BN
This review of the effects of treatment for urinary tract
infection in children and of preventive interventions is
one of over 60 chapters in the first issue of Clinical
Evidence, published by the BMJ Publishing Group.
Key messages:
Treating symptomatic acute urinary tract infection in
children with an antibiotic is accepted clinical practice
and trials would be considered unethical
We found little evidence on the effects of delaying
treatment while awaiting microscopy or culture results,
but retrospective observational studies suggest
delayed treatment may be associated with increased
rates of renal scarring
One systematic review of randomised controlled trials
(RCTs) has found that antibiotic treatment for seven
days or longer is more effective than shorter courses
We found no convincing evidence of benefit from routine
diagnostic imaging of all children with a first urinary tract
infection, but subgroups at increased risk of future
morbidity may benefit from investigation. Because such
children cannot currently be identified clinically,
investigating all young children with urinary tract
infection may be warranted
Two small RCTs found that prophylactic antibiotics
prevented recurrent urinary tract infection in children,
particularly during the period of prophylaxis. The long
term benefits of prophylaxis have not been adequately
evaluated, even for children with vesicoureteric reflux.
The optimum duration of treatment is unknown
One systematic review and a subsequent multicentre RCT
found no difference between surgery for vesicoureteric
reflux and medical management in preventing recurrence
or complications from UTI
Practice at NSMC
33 cases of Hx entry UTI over 3 years
 Age range 1year – 14years
 Symptoms including abdo pain, dysuria,
frequency, vomiting, fever, wetting
 15% no symptoms recorded
 72% urine dip recorded, 7 did not, 2
noted not possible
 All those with urine dip reported positive
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Prescribing for UTI
NSMC
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Of all positive dips all but 2 had ABX
immediately
2 positive dips awaited MSU before Rx
Where dip not possible 2 awaited MSU
before Rx
17 had Trimethoprim, 9 Amox/Amp, 1 Cipro
Length of Rx ranged from 3 – 10days
(Trimethoprim 10 days, Amp 5 days)
MSU
63% had MSU result
 21% had MSU mentioned in Hx but not
result appeared
 39% MSU positive
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Referral
50% positive MSUs were referred on
first infection
 2 negative MSUs were referred
 4 were referred after subsequent
infections
 3 investigated in house with USS
 1 not referred (seen at hospital)
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Issues
Hx entries, symptom recording
 Prescribing
 MSUs
 FU and referral – esp from hospital
 In house investigation?
 Haematuria??
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Consider the issue of
antibiotic prescribing
in sore throat ~
What is the problem?
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Double blind RCTs suggest
antibiotics give only marginal
benefit when prescribed for
common acute respiratory illnesses
 Yet antibiotics are still widely
prescribed in this situation
 Is the problem that doctors do not
feel that RCTs are applicable to the
usual practice setting?
Paper for discussion:
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“Open randomised trial of prescribing
strategies in managing sore throat”
Little et al, BMJ 1997, 314, 722 (8th
March)
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The objective of this study was to
assess three prescribing strategies for
sore throat – antibiotics, no antibiotics
or deferred prescription for antibiotics
Description of paper - 1
Objective – to assess three
prescribing strategies for sore
throat
 Open randomised follow-up
study – involved discussion with
patients
 Provides another model for
clinical management
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Description of paper - 2
Setting – 11 practices in South and West
Region
 716 patients with ST and an abnormal
physical sign in the throat – 84% had
“tonsillitis” or “pharyngitis”
 Patients randomised to three groups:
antibiotics for 10/7 (246), no prescription
(230), prescription to be used if symptoms
were not settling after 3/7 (238) – in fact
add to 714
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Results - 1
10
9
8
7
6
5
4
3
2
1
0
Days of Rx
Illness duration
Days off
Rx
No Rx
Defer
Results - 2
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
Better at 3/7
Pt satisfied
Thought Rx
effective
Intended to
come in future
Rx
No Rx
Defer
Results - 3
69% of patients in deferred group did
not use the prescription
 Legitimisation of illness for school or
work (60%) was an important reason
for consultation
 Patients who were more satisfied
with the way the doctor dealt with
them got better more quickly
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Conclusion in paper
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“Prescribing antibiotics for sore
throat only marginally affects the
resolution of symptoms but
enhances belief in antibiotics and
intention to consult in future when
compared with the acceptable
strategies of no prescription or
delayed prescription”.
Another paper
“A RCT of delayed antibiotic
prescribing as a strategy for
managing uncomplicated respiratory
tract infection in primary care”.
Dowell et al, BJGP, 2001, 464, 200
(March)
 Reached similar conclusions.
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What this means
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Antibiotics are not always needed
for sore throat to resolve
 Strategy of deferred prescription
can reduce antibiotic usage
 Patients can be managed in this
way and still remain happy with
their care
Next steps
Can this idea be generalised?
 What about acute cough?
 What about conjunctivitis?
 What about otitis media?
 What about sinusitis?
 Other conditions?
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