Complement Diagnosis of Acute Appendicitis
Complement Diagnosis of Acute Appendicitis
Acute appendicitis is a common condition requiring urgent surgery but is often difficult to
 distinguish from other non-surgical conditions such as urinary infections, pelvic
 inflammatory disease and non-specific abdominal pain. Delay in diagnosis can result in
 significant morbidity and potential mortality. Currently, there is no one diagnostic test
 available and raised inflammatory markers such as C-reactive protein (CRP) and White Blood
 Count (WBC) along with an evolving clinical picture, help guide management. However, these
 markers are slow to respond to inflammation and are non-specific for appendicitis. The
 Complement cascade is an immune response to inflammation and infection involving three
 pathways which activate a number of proteins in the blood. Monitoring the absolute levels of
 these proteins should provide a faster and differential diagnostic test. The investigators
 propose a pilot trial to measure concentrations of Complement cascade activation biomarkers
 in the blood during hospital admissions for acute right lower abdominal pain, a symptom of
 appendicitis. Further, analysis of the differential Complement cascade pathway activation
 could potentially identify underlying pathology allowing the clinicians to target therapies.
The proposed study is a pilot study on a cohort of participants recruited at emergency
 admission with acute right iliac fossa pain (right lower abdominal pain) to the Royal Devon &
 Exeter Hospital Accident & Emergency department. The pilot trial will collect one urine
 sample on admission and blood over a time course for each patient to record blood plasma
 levels of Complement proteins during hospital admissions with suspected appendicitis. The
 assay schedule is detailed in Table 1 below. The trial will perform additional Complement
 cascade activation tests on routine blood samples taken during the patient's stay in
 hospital. In addition 3 trial samples will be taken at time intervals that will capture the
 early Complement cascade response. Those patients going onto surgery will have a total of 5
 additional trial samples taken, with 2 samples taken intra-operatively whilst under
 anaesthesia. From our previous experience in a similar pilot study CPOP (Complement cascade
 Predictors of Procedural Outcome), the investigators have introduced a blood taking 'curfew
 window' in which trial sample No. 2 & 3 must not take place between the hours of midnight and
 0600 hrs. This is to incorporate the wishes of patients and improve compliance with the
 study. Sample analysis will be performed in parallel in the clinical chemistry laboratory for
 assays of CRP and the complement proteins C3 and C4. The additional trial assays will be
 performed by Prof Shaw's research post doctoral assistant in the clinical chemistry
 laboratory and in the Medical School. A fresh frozen urine sample will be acquired from the
 routine urine sample given on all admissions for RIF pain. This urine sample will be analysed
 for Complement activation products such as C3a and C5a. Diagnostic end points will be
 acquired through the routine management of these patients and accessed via the hospital
 imaging (PACS) and pathology (IHCS) reporting system. These will include appendix histology
 and microbiology, urinalysis, blood cultures, imaging and cervical swabs.

 Table 1Blood Sample Assay Schedule Time Point Time of Test Routine Test Additional Trial Test
 Trial Assays Day Timings (example) PM Timings (example)

 1. t = 0 Admission to A&E

 CONSENT ROUTINE:

 WCC, CRP, LFTs, Amylase, Clotting. Urinalysis.

 On attending clinicians discretion:

 urine culture, blood cultures, cervical swabs, imaging: US, CT, mri. Serum: C3, C4,
 C3dg, compliment activation markers

 Urine: compliment activation markers eg: C3a, C5a. 09:00 hrs 18:00 hrs

 2. t = 1-4 h CONSENT(if not previously obtained) 09:00 to 13:00 hrs 1800 to 22:00 hrs

 3. t = 4 h Trial Sample NO.1 C3, C4, C3dg,compliment activation markers 13:00 hrs 22:00 hrs

 4. t =8h Trial Sample NO.2 C3, C4, C3dg, compliment activation markers 17:00hrs 02:00 hrs

 No action: 'blood taking curfew'

 5. t = 12 h Trial Sample NO. 3 C3, C4, C3dg, compliment activation markers 21:00 hrs 06:00
 hrs

 No action: 'blood taking curfew'

 6. t = 23 h ROUTINE C3, C4, C3dg, compliment activation markers 08:00hrs t = 14 h 08:00 hrs

 7. t = 47 h ROUTINE C3, C4, C3dg, compliment activation markers 08:00hrs t = 38 h 08:00 hrs

 8. t = 71 h

 Some Patients Discharged

 Some patients for Laparoscopy ROUTINE C3, C4, C3dg, compliment activation markers
 08:00hrs t = 62 h 08:00 hrs

 9. If for surgery:

 t = surg0

 On Induction Trial Sample NO. 4 C3, C4, C3dg, compliment activation markers, CRP 09:00
 hrs t = surg 0 21:00 hrs

 10. t = surg 45 min

 End of surgery Pathology: appendix specimen Microbiology: appendix swabs Trial Sample
 NO. 5 C3, C4, C3dg, compliment activation markers, CRP 09:45 hrs t = surg 60 min 22: 00
 hrs

 11. t = x d, y h (days, hours from t0) Routine tests as they occur C3, C4, C3dg, compliment
 activation markers, CRP

 12. Discharge

 If readmitted within 14 days

 tR=x d, y h(days, hours from t0) ROUTINE C3, C4, C3dg, compliment activation markers, CRP

 The assays deployed for the CDAA pilot trial will include the current biomarkers of
 Complement consumption, C3 and C4, available in the clinical chemistry laboratory; in
 addition the investigators will use a panel of activation markers including C3dg, C4d, Bb and
 TCC that have been developed during the CPOP clinical trial. Prof Shaw's group now has
 extensive experience with the development, optimisation and internal auditing of the
 activation assays. The assay for the trial will be performed in Prof Shaw's laboratory in
 parallel with the clinical chemistry laboratory who will be responsible for producing
 aliquots from the plasma
Inclusion Criteria:

 -  Admission for right iliac fossa pain

 Exclusion Criteria:

 Under 18 years unwilling to provide informed consent pregnant women diabetic
 immunosuppressed immunosuppression or steroid treatment within last 12 months learning
 disability Non-english speakers