DIAgnostic iMaging or Observation in Early Equivocal appeNDicitis (DIAMOND)

DIAgnostic iMaging or Observation in Early Equivocal appeNDicitis - a Randomized Controlled Trial

The aim of the study is to evaluate whether patients with early equivocal appendicitis can be observed instead of immediate diagnostic imaging. Half of the patients are randomly assigned to observation group, while the other half will undergo diagnostic imaging. The hypothesis is that resolving appendicitis is common in these patients. Thus, in observation group there will be fewer patients with appendicitis diagnosis and observation reduces the use of diagnostic imaging and surgery.

Study Overview

• Status: Completed
• Conditions: Appendicitis
• Intervention / Treatment: Other: Observation; Other: Diagnostic imaging

Detailed Description

For the study equivocal appendicitis is defined as clinical suspicion of appendicitis with Adult Appendicitis Score between 11 and 15. The estimated prevalence of appendicitis in such patients is around 50%.

Diagnostic imaging is done using conditional computed tomography i.e. abdominal ultrasound first and computed tomography only after negative or inconclusive appendicitis after ultrasound.

In observation group repeated clinical examination is done after 6-8 hours interval with repeated blood test for calculation of Adult Appendicitis Score. Patients with decreasing score value continue observation without imaging, whereas patients with the same score value or higher (but below 16) undergo diagnostic imaging as in other group. Laparoscopy is done without imaging in patients with high score (16 or higher). Antibiotics are not allowed, but prophylactic antibiotics during induction of anesthesia are allowed.

• Study Type: Interventional
• Enrollment (Actual): 185
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Finland
  • Helsinki, Finland, 00029
    • Helsinki University Central Hospital, Meilahti Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Clinical suspicion of acute appendicitis
• Equivocal appendicitis defined by Adult Appendicitis Score: Score ≥11 and ≤15.

Exclusion Criteria:

• C-reactive protein >99 mg/l
• Time from symptom onset over 24 hours
• Pregnancy
• Antibiotics given within last 24 hours
• Suspicion of other disease than appendicitis, that would require immediate interventions such as surgery, diagnostic imaging or gynecologic consultation
• Missing written informed consent
• Patient randomized earlier to the study

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Observation; Clinical follow-up for at least 6-8 hours, after follow-up repeated laboratory tests and repeated clinical examination is done. Adult Appendicitis Score is calculated after observation to determine further actions. Observation is continued in patients with decreasing score. Patients with the same or higher score undergo diagnostic imaging (score 11-15) or laparoscopy (score 16 or higher). Diagnostic imaging is abdominal ultrasound first and if the result is inconclusive or negative for appendicitis abdominal computed tomography is done. Laparoscopic appendectomy is done for those patients with appendicitis in diagnostic imaging.	Other: Observation; Observation for 6 to 8 hours. After observation period repeated clinical examination and repeated blood test for calculation of Adult Appendicitis Score is done.
Active Comparator: Diagnostic imaging; Patients undergo abdominal ultrasound and if the result is inconclusive or negative for appendicitis patients will have abdominal computed tomography. Laparoscopic appendectomy is done for patients with appendicitis in diagnostic imaging.	Other: Diagnostic imaging; Abdominal ultrasound, followed by abdominal computed tomography when necessary

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Appendicitis requiring surgery or other intervention	30 days from randomization

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Complicated appendicitis	Perforated appendicitis or appendiceal abscess	30 days from randomization
Delayed appendicitis diagnosis	Diagnosis is delayed if appendicitis is diagnosed later than 24 hours from randomization	30 days from randomization
Number of diagnostic imaging studies needed	Number of abdominal ultrasound and abdominal computed tomography per patient	30 days from randomization and within 1 year after randomization
Appendicitis requiring surgery or other intervention		within 1 year after randomization
Negative appendectomy	Laparoscopy done for suspected appendicitis, but patient does not have appendicitis	30 days from randomization
Number of re-admissions to emergency unit	Any reason for re-admission are accounted	1 year
Number of other clinically relevant findings	Findings unrelated to appendicitis	30 days from randomization
Number of patients requiring of gynecological consultation	Applicable only in female patients	30 days from randomization
Time for decision	The time from randomization to either decision to operate in appendicitis patients or to discharge in non-appendicitis patients.	30 days from randomization

Collaborators and Investigators

• Sponsor: Helsinki University Central Hospital
• Investigators: Principal Investigator: Panu J Mentula, M.D. Ph.D., Helsinki University Central Hospital

Publications and helpful links

General Publications

• Sammalkorpi HE, Mentula P, Leppaniemi A. A new adult appendicitis score improves diagnostic accuracy of acute appendicitis--a prospective study. BMC Gastroenterol. 2014 Jun 26;14:114. doi: 10.1186/1471-230X-14-114.
• Lastunen KS, Leppaniemi AK, Mentula PJ. DIAgnostic iMaging or Observation in early equivocal appeNDicitis (DIAMOND): open-label, randomized clinical trial. Br J Surg. 2022 Jun 14;109(7):588-594. doi: 10.1093/bjs/znac120.

Helpful Links

• Original publication of Adult Appendicitis Score
• Online calculator for Adult Appendicitis Score

Study record dates

Study Major Dates

• Study Start (Actual): April 1, 2016
• Primary Completion (Actual): April 9, 2020
• Study Completion (Actual): April 30, 2021

Study Registration Dates

• First Submitted: April 7, 2016
• First Submitted That Met QC Criteria: April 13, 2016
• First Posted (Estimate): April 19, 2016

Study Record Updates

• Last Update Posted (Actual): August 25, 2021
• Last Update Submitted That Met QC Criteria: August 24, 2021
• Last Verified: August 1, 2021

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Digestive System Diseases; Infections; Gastrointestinal Diseases; Gastroenteritis; Intestinal Diseases; Cecal Diseases; Intraabdominal Infections; Appendicitis
• Other Study ID Numbers: HUS/95/2016

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO