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Trial details imported from

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Registration number
Ethics application status
Date submitted
Date registered
Date last updated

Titles & IDs
Public title
Non-operative Management for Appendicitis in Children
Scientific title
A Prospective Randomised Controlled Non-inferiority Study to Evaluate the Effectiveness and Safety (APRES) of Non-operative Management in Children With Acute Uncomplicated Appendicitis
Secondary ID [1] 0 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Acute Focal Appendicitis 0 0
Appendicitis 0 0
Condition category
Condition code
Surgery 0 0 0 0
Other surgery

Study type
Description of intervention(s) / exposure
Treatment: Drugs - Non-operative management group (NOM)
Treatment: Surgery - Appendectomy group (Operative management, OM)

Experimental: Non-operative management group (NOM) - Children in the NOM group will receive intravenous Piperacillin with Tazobactam (Tazocin) 100mg/kg/dose every 8 hours for at least 24 hours, and they will be observed and reassessed within 24 hours after randomisation. A further 24 hours of intravenous Piperacillin with Tazobactam therapy will be offered to children in invariable condition. A clinical decision will be made by the attending surgeon to offer OM if a patient's condition deteriorates at any time, or if a patient has failed to improve after 48 hours of intravenous antibiotic therapy. Once the patient is clinically improving and tolerating oral intake, the antibiotic regimen will be changed to oral Amoxicillin plus Clavulanic acid (Augmentin) 22.5mg/kg/dose twice per day to complete a total seven day course of antibiotics. Oral Ciprofloxacin 15mg/kg/dose twice daily and oral Metronidazole 10mg/kg/dose twice daily will be offered to children who are known to have an intolerance or allergy to Amoxicillin or Clavulanic acid.

Active Comparator: Appendectomy group (Operative management, OM) - Children allocated to OM may receive preoperative antibiotic prophylaxis as clinically indicated. Appendicectomy will be performed laparoscopically, or via open surgery according to the surgeon's standard practice. Postoperative antibiotic treatment will be determined on the basis of intraoperative findings in accordance with the institutional practice. The appendix specimen will be examined by a paediatric pathologist, and the formal histopathology report will be recorded.

Treatment: Drugs: Non-operative management group (NOM)
With intravenous Piperacillin with Tazobactam (Tazocin)

Treatment: Surgery: Appendectomy group (Operative management, OM)

Intervention code [1] 0 0
Treatment: Drugs
Intervention code [2] 0 0
Treatment: Surgery
Comparator / control treatment
Control group

Primary outcome [1] 0 0
Unplanned or unnecessary operation(s) and complications
Timepoint [1] 0 0
30 days
Secondary outcome [1] 0 0
Unplanned or unnecessary operation, or complications
Timepoint [1] 0 0
6 months
Secondary outcome [2] 0 0
Length of primary hospital stay - Time of randomisation to discharge
Timepoint [2] 0 0
72 hours
Secondary outcome [3] 0 0
Treatment-related complications
Timepoint [3] 0 0
12 months
Secondary outcome [4] 0 0
Redamission and Emergency Department presentation
Timepoint [4] 0 0
12 months
Secondary outcome [5] 0 0
Cost of treatment in Australian Dollars (AUD)
Timepoint [5] 0 0
12 months
Secondary outcome [6] 0 0
Return to school from time of randomisation
Timepoint [6] 0 0
30 days
Secondary outcome [7] 0 0
Return to normal activities from time of randomisation
Timepoint [7] 0 0
30 days

Key inclusion criteria
1. Age between 5 and 15 years;

2. Clinical diagnosis by at least one paediatric surgeon (or duty surgical registrar) of
acute uncomplicated appendicitis based on with a combination of clinical, laboratory
and/or imaging findings; that before the study would have led to the decision to
recommend been subjected to an appendicectomy.
Minimum age
5 Years
Maximum age
16 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
if one or more of the following is assessed to be present

1. Suspicion of perforated appendicitis on the basis of generalised peritonitis and/or
imaging studyA diagnosis of perforated or complicated appendicitis (e.g. peritonitis,
appendiceal mass) is made on the basis of clinical, laboratory and/or imaging

2. Previous non-operative treatment of acute appendicitis;

3. Age younger than 5 years or older than 16 years;

4. Known intolerance or allergy to Piperacillin with Tazobactam;

5. Known history of inflammatory bowel disease, or other chronic abdominal pain syndrome;

6. Known concurrent significant illness;

7. Unable to obtain informed consent from parents or guardian;

8. Known to have a cognitive impairment, an intellectual disability or a mental illness
that would impair participation.

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?

Intervention assignment
Other design features
Not Applicable
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Unknown status
Data analysis
Reason for early stopping/withdrawal
Other reasons
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)
Recruitment hospital [1] 0 0
Sydney Children's Hospital - Randwick
Recruitment hospital [2] 0 0
The Children's Hospital at Westmead - Westmead
Recruitment postcode(s) [1] 0 0
2031 - Randwick
Recruitment postcode(s) [2] 0 0
2145 - Westmead

Funding & Sponsors
Primary sponsor type
Sydney Children's Hospitals Network

Ethics approval
Ethics application status

Brief summary
This study is designed to determine the safety and efficacy of non-operative antibiotic
management of clinically diagnosed acute uncomplicated appendicitis in children. Enrolled
patients will be randomised and an allocation ratio of 1:1 will be made via weighted
minimisation, where half of the patients will receive non-operative management with
intravenous Piperacillin with Tazobactam, while the other half will have an appendicectomy.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 0 0
Address 0 0
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for public queries
Name 0 0
Susan Adams, MBBS
Address 0 0
Country 0 0
Phone 0 0
61 02 9382 1776
Fax 0 0
Email 0 0
Contact person for scientific queries

Summary results
For IPD and results data, please see