Can normal inflammatory markers rule out acute appendicitis? The reliability of biochemical investigations in diagnosis. Issue 10 (12th November 2019)

• Record Type: Journal Article
• Authors: Kim, Jason J. Y.; Dobson, Benjamin H.; L. H. Ng, Cedric; Thong, Da Wei; Arthur, Thomas; Parker, David
• Other Names: Anwari Tahmina investigator.; Archer Leigh investigator.; Auld Michael investigator.; Bagguley Dominic investigator.; Bhatt Jubin investigator.; Bierton Christopher investigator.; Bormann Sarah investigator.; Bradshaw Kimberley investigator.; Callahan Rosie investigator.; Capati Gian investigator.; Cattanach Daniel investigator.; Chai Debbie investigator.; Cozier Matthew investigator.; Daza Fermina investigator.; Della Martina Olivia investigator.; Dickfos Marilla investigator.; Duncan Catriona investigator.; Edward Laura investigator.; Elstner Kristen investigator.; Franceschini Luke investigator.; Fuller Emma investigator.; Gavey Roderick investigator.; Goldman Hariette investigator.; Gole Hobia investigator.; Harrison Elizabeth investigator.; Honore Matthew investigator.; Hughes Ian investigator.; Hwang Yang investigator.; Jacob Matthew investigator.; Jain Anshini investigator.; Jones Stephanie investigator.; Kothapalli Anita investigator.; Kwok Michael investigator.; Lavarack Bruce investigator.; Lee Lisa investigator.; Liu David investigator.; Lonie James investigator.; Low Nicholas investigator.; Mackrill David investigator.; Maddern Guy investigator.; McFarlane Julia investigator.; Metcalfe Dinusha investigator.; Moar Xavier investigator.; Morden Brendon investigator.; Nabi Hajir investigator.; Nice Neo Eu investigator.; Ying Kin Daniel Ng investigator.; O'Brien Eavan investigator.; O'Donohue Peter investigator.; Paget Sarah investigator.; Potent Keith investigator.; Puhalla Harald investigator.; Ramachandran Roshan investigator.; Rosley Muhammad investigator.; Schachtel Michael investigator.; Schmidt Amy investigator.; Sharpe Kendall investigator.; Shivananda Arjun investigator.; Stupart Douglas investigator.; Ta'I Shayan investigator.; Theophilus Mary investigator.; Toonsen Phill investigator.; Udovicich Cristian investigator.; Van Der Nest Bianca investigator.; Walch Anna investigator.; Walker Daniel investigator.; Wong Enoch investigator.; Hame Wong Zee investigator.; Zubair Omar investigator.;
• Is Part Of: ANZ journal of surgery. Volume 90:Issue 10(2020)
• Page Start: 1970
• Page End: 1974
• Publication Date: 2019-11-12
• Subjects: appendicitis -- C‐reactive protein -- inflammatory marker -- white cell count; Surgery -- Periodicals; 617.005
• DOI: 10.1111/ans.15559
• Languages: English
• ISSNs: 1445-1433

Abstract

Abstract: Background: Acute appendicitis is a common general surgical condition where diagnosis is predominantly clinical, with the aid of adjunct investigations. This study reviews the relationship between normal and elevated biochemical inflammatory markers, duration of symptoms and proven appendicitis. Methods: A multicentre prospective observational study was performed across 27 centres and included a total of 949 patients with clinical suspicion of appendicitis, who had both white cell count (WCC) and C‐reactive protein (CRP) recorded and underwent appendicectomy. Results: A total of 90.4% of patients with raised WCC and CRP had appendicitis with a positive predictive value (PPV) of 0.9 and negative predictive value (NPV) of 0.4. Sensitivity and specificity of elevated WCC (sensitivity 66.5%, specificity 66.0%) and elevated CRP (sensitivity 77.3%, specificity 52.0%) lie within ranges identified by previous studies. A total of 39.8% of patients with normal CRP and WCC had appendicitis. Sensitivity and PPV for patients with elevated inflammatory markers were high until 48 h of symptoms (sensitivity 94%, PPV 0.87). NPV was elevated after 24 h (NPV 0.65 in patients with 24–48 h of symptoms, and 0.61 after 48 h), whilst those with symptoms less than 24 h had a lower NPV of 0.52. Conclusion: Whilst elevated inflammatory markers are a helpful aid in the diagnosis of appendicitis, they should not be relied on by themselves. Nor can normal inflammatory markers be used to exclude appendicitis, even in those with prolonged duration of symptoms. The diagnosis of appendicitis should be guided by a combination of clinical judgement with the assistance of inflammatory markers.