Singleton Minor Injuries Unit
Typical Class II Cellulitis Pathway-Out Patient Ambulatory
Treatment (OPAT)
February 2010-Dr Chris Johns (07967806603)
Background
Many patients are often admitted to hospital unnecessarily for Intravenous antibiotics for
Class II Cellulitis. Cellulitis in adults is a common medical condition taking up a large number
of occupied bed days in Acute hospitals. In 1985 in the UK, skin and subcutaneous tissue
infections resulted in 29,820 hospital admissions and a mean occupancy of 664 hospital
beds each day 1. One survey concluded that it accounted for around 3% of emergency
medical consultations at a UK district general hospital.
The classification system
Eron LJ (2000) devised this classification system of skin and soft tissue infections to aid
the GP/Nurse diagnosis, treatment and admission decisions.
Class I patients have no signs of systemic toxicity, have no uncontrolled co-morbidities
and can usually be managed with oral antimicrobials.
Class II patients are either systemically ill or systemically well but with a co-morbidity such
as peripheral vascular disease, chronic venous insufficiency or morbid obesity which may
complicate or delay resolution of their infection.
Class III patients may have a significant systemic upset such as acute confusion,
tachycardia, tachypnoea and hypotension or may have unstable co-morbidities that may
interfere with a response to therapy or have a limb threatening infection due to vascular
compromise.
Class IV patients have sepsis syndrome or severe life threatening infection such as
necrotizing fasciitis.
Clinical findings alone are usually adequate for diagnosing cellulitis, particularly in
non-toxic immunocompetent patients.
In the past, it has been standard practice to hospitalize Class II patients with serious soft
tissue infections, such as cellulitis. However, those of Class II severity can usually be treated
safely and effectively with OPAT followed by transition to oral agents as the infection
resolves.
Ceftriaxone has been listed for the management of Class II infections. This agent is
administered once daily making it a suitable agent if OPAT is locally available and considered
appropriate. Its safety and efficacy in this situation is well established. It is relatively cheap
ABMU Health Board presently buying a 2g vial of Ceftriaxone at £1.63p
There are community pathways available that have been developed but there have been
workload implications for already stretched community services and problems with patients
needing to re-attend secondary care for cannulae care. In addition community medical
assessment and review is not always possible.
Singleton Minor Injuries Unit is ideal to deliver OPAT. Patients can be referred from Accident
and Emergency and other secondary care specialities. Singleton MIU can provide daily iv
antibiotics, cannula care, ongoing assessment and conversion to oral antibiotics when
appropriate.
Exclusion Criteria
If the patient has any criteria listed below they are not suitable for outpatient IV
treatment of cellulitis.
1. Hypersensitive (allergic) to Penicillin or Cephalosporins
2. Pregnant/lactating women [subject to clinical review]
3. Hepatic and/or renal disease
4. Neutropenia
5. Concurrent, uncontrolled illness
6. Inability to manage at home due to present circumstances - e.g.: Support
services/Carer : Effects of condition
7. Likelihood of non-compliance
8. Facial/Orbital cellulitis
9. Class 3 & 4 Cellulitis
10. Known colonisation with Ceftriaxone resistant organism e.g. MRSA
(discuss with Microbiology)
11. Age 16 or under
Referrals
Referrals are accepted by Singleton Minor Injuries for ambulatory management of Class II
cellulitis by telephone on 0179 2281582 and patient details faxed to 01792 298347.
Referrals can be accepted after diagnosis from the secondary care team. In most cases it is
anticipated the first dose of iv antibiotics would be administered by the secondary care
team at Morriston or Singleton Hospital.
Specialities with access to pathway
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Morriston A+E
Burns and Plastics Morriston
Singleton MIU
General Medicine Morriston and Singleton
Morriston Trauma and Orthopaedics
General Surgery Morriston and Singleton

Singleton Dermatology
DVT pathway
The DVT pathway in MIU has been running for 6 weeks. Patients are being seen and treated
very quickly and initial figures a good pick up rate with reference to positive scans. Some
DVT patients will suffer secondary problems with post thrombotic syndrome and a cellulitis
pathway facets in well with the DVT service
Clinical issues (http://www.crestni.org.uk/cellulitis-guide.pdf)
Cellulitis presents as the acute and progressive onset of a red, painful, hot, swollen and
tender area of skin. The edge of the erythema may be well demarcated or more diffuse and
typically spreads rapidly. Constitutional upset with fever and malaise occurs in most cases,
and may be present before the localising signs. Blistering/bullae, superficial haemorrhage
into blisters, dermal necrosis, lymphangitis and lymphadenopathy may occur . The leg is the
commonest site and there may be an identifiable portal of entry, for example, a wound, an
ulcer or signs of tinea infection. Bilateral leg cellulitis is extremely rare. The use of simple
clinical diagnostic criteria should be encouraged and should avoid over diagnosis and
inappropriate investigations and antibiotics . The absence of typical clinical features should
make one think of the main differential diagnoses, especially:
1.Varicose eczema which is often bilateral with crusting, scaling and itch or other lower leg
eczema.
2. DVT with pain and swelling without significant erythema.
3. Acute liposclerosis which may have pain, redness and swelling in the absence of
significant systemic upset .
Other differential diagnosis include lower leg oedema with secondary blistering, erythema
nodosum, other panniculities or vasculitis and pyoderma gangrenosum.
Complications include fasciitis, myositis, subcutaneous abscesses, septicaemia, post
streptococcal nephritis and death.iianan
II2
Investigations
Although non-specific, nearly all patients have a raised white cell count and elevated ESR or
C-reactive protein. Normal results make a diagnosis of cellulitis less likely.
Culture of any local lesion is generally unrewarding – intradermal needle aspiration yielding
positive culture results in around 10% of cases and punch biopsy in 20% 6. However where
there is an open wound, drainage or an obvious portal for microbial entry, a swab should be
taken for culture.
Blood cultures are rarely positive (2-4%) and contaminants may outnumber pathogens .
Blood cultures should not be undertaken routinely but be reserved for patients where the
infection has been graded as Class III or Class IV where they are more likely to yield the
causative organism.
Serological tests such as ASOT or AntiDNAse B only provide retrospective evidence in
selected refractory cases.
Class II Cellulitis should be investigated with FBC, ESR/CRP, U+E and Culture of any skin
break, serous leak or blister fluid. In this Class there is no evidence that Blood Cultures,
Streptococcal Serology or Skin Biopsy is helpful
Suitable Treatment Regimes for Typical Class II Cellulitis
Flucloxacillin 2g iv qds or Ceftriaxone 1g iv od (OPAT) (no history of Penicillin
allergy/anaphylaxis)
Penicillin allergy: It is essential to obtain a detailed history of a patient’s reaction to
penicillin as this may allow a clinician to exclude allergy. The vast majority of patients with a
history of penicillin rash tolerate cephalosporins without significant reaction . If the patient
has experienced an anaphylactic reaction or immediate urticarial rash to a penicillin, this
class of drug must be avoided. Macrolide antibiotics or clindamycin are suitable alternatives.
( Clarithromycin 500mg iv bd or Clindamycin 600mg iv bd)
In the past, it has been standard practice to hospitalize Class II patients with serious soft
tissue infections, such as cellulitis. However, those of Class II severity can be treated safely
and effectively with OPAT followed by transition to oral agents as the infection resolves.
Ceftriaxone has been listed for the management of Class II infections. This agent is
administered once daily making it a suitable agent if OPAT is locally available and
considered appropriate. Its safety and efficacy in this situation is well established.
Although criteria for the switch from parenteral to oral antibiotics for patients with
community acquired pneumonia have been studied there is less information in relation to
cellulitis. It has been suggested that patients can be switched safely to oral antibiotics within
3.5 days of therapy for uncomplicated cellulitis . Use of IV therapy for longer than 3-4 days
in these uncomplicated cases does not correlate with better outcomes.
Criteria for change to oral therapy
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Pyrexia settling
Co-morbidities stable
Less intense erythema
Falling inflammatory markers
Suitable oral regimes
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Flucloxacillin 500mg qds for 14 days
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Clarithromycin 500mg bd (Penicillin allergy) for 14 days
Clindamycin 300mg qds (Penicillin allergy) for 14 days
Minor Injury Unit Pathway Proposal
Singleton Minor Injuries Unit is an ideal clinical environment for the delivery of OPAT for
Class II cellulitis. Patients can be referred by secondary care after initiation of management.
Benefits
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Avoids unnecessary admission to hospital
Transfers work from stretched Morriston A+E
Close contact with other specialities-Podiatry, Dermatology, Vascular etc.
Avoids Community problems with overstretched District Nursing and cannula care
Quality of service for patients-waits etc
Maximise MIU time when not functioning as Out of Hours Service.
Joint working between GP’s and Hospital
Ambulatory Care Model-future for Singleton Hospital
Closer contact with Primary Care on discharge
Enhance the position of MIU
Test the water for future service provision?-direct GP referral?
Timescales
If the proposal is accepted the pathway could start 1st Sept 2010 which would allow 6
months of the DVT pathway to run and to develop the pathway further.
Patient Numbers
It is almost impossible to establish accurately the likely numbers of referrals as the exclusion
criteria and multiple referral routes from specialities make measurements difficult.
Morriston A+E are looking at likely referral numbers. It may be that the pathway will begin
without an accurate forecast and will have to react to referral numbers and patterns
accordingly.
Resource Implications
There may be need, particularly given the workload implications of the DVT pathway, the
need to look at Nursing rota adjustments as two nurses during the day would be ideal to
cover both the DVT pathway and the Cellulitis pathway in addition to “walk in” minor
injuries. As the work in predictable the pathway will run 7 days a week 9am until 6pm,
alongside the DVT pathway. It is unlikely there would be any medical staff resource issue as
this work can be absorbed in present structures.
Additional information
http://www.crestni.org.uk/cellulitis-guide.pdf
http://www.prodigy.nhs.uk
http://www.cks.nhs.uk/clinical_knowledge/clinical_topics/previous_version/cellulitis.pdf
Algorithm
See below
Algorithm for OPAT of Typical Class II CellulitisSingleton Minor Injuries Unit
Patients presents to Morriston A+E (or
other secondary care speciality) with
Class II Cellulitis and suitable for OPAT.
Patient assessed, investigated,
observations recored, iv cannula sited,
erythema marked. First dose of iv
antibiotics given. Patient is referred by
telephone/fax to MIU and appointment
time given for next day
Patient attends MIUdaily for
iv antibiotics (Ceftriaxone iv),
further assessment and
cannula care
No Clinical improvement or
deteriorating signs and
symptoms at any time
Patient referred to
appropriate secondary care
team for further
management or admissionMedical, Surgical,
Dermatology or
Microbiology
Clinical improvement after
4 days iv antibiotics
(Ceftriaxone 1g)
Converted to oral
antibiotics. Flucloxacillin
500mg qid for 14 days
Patient discharge to GP with
recommendations for follow
up in 7 days and need for
Outpatient referralDermatology, Surgical,
Lymphoedema or antibiotic
prophylaxis if 2 or more
episodes at same site