Dr. Kevin Fairbairn (biography, no disclosures)
What I did before
Appendicitis can often present itself in the black box of abdominal pain. Fortunately at times the history and physical can give practitioners a clear window, straight through the fascia, to an unhappy appendix. After making a clinical diagnosis I would get on my game face and weave a convincing story, filled with compelling characters and an intricate plot, for my surgical consultation. This all is done with the hope of arriving at decision for definitive imaging.
What changed my practice
Alvarado Score 1 :
|Migrating pain to RLQ||1|
|Left shift of neutrophils||1|
*modified score includes leukocytosis, but excludes Left shift 2
Free app availability includes Calculate QxMD: https://www.qxmd.com/calculate/calculator_269/alvarado-score-for-acute-appendicitis and mdcalc – online, app in beta testing: http://www.mdcalc.com/alvarado-score-for-acute-appendicitis/.
Pay apps: mediquations, medfixation (http://www.medfixation.com http://www.mediquations.com).
The Alvarado score isn’t new. It was first suggested in 1986 and while it is primarily clinical it does take into consideration differential white blood cell count. 1 A modified score was then developed to allow the use of this tool in resource limited settings without access to basic lab work (white cell differential). 2 Since then there have been several important studies outlining the usefulness and pitfalls of these tools. The Alvarado score has been validated multiple times with high sensitivities >93% in adult men with scores >7; however low sensitivities (67%) and high false positives in female populations. 2-4
More recently an observational study in 2012 observed that a low modified Alvarado score was not helpful in ruling out appendicitis. 5 Low scores of <4 had a only a sensitivity of 72% and specificity of 54% whereas clinical judgement yielded a sensitivity and specificity of 93% and 33% respectively. 5 This was contrary to a 2011 meta analysis suggestive that Alvarado scores <5 were able to rule out appendicitis with sensitivities from 94% to 99%. 6 In these cases observation and serial assessment may provide a reasonable option. 6
Unfortunately similar controversy exists in the pediatric population. One recent meta analysis suggests that the Alvarado score may be applicable in the setting of appropriate pretest probability. 7 However, a 2013 systematic review noted that neither the Alvarado score nor the Pediatric Appendicitis Score out performed the benchmark of >95% sensitivity (used for several other clinical prediction rules). 8,9
In regards to imaging scores in the 4-6 range have traditionally led to further radiographic work up. 10,11 CT scans in the equivocal group (4-6) improved sensitivity and specificity from 35.6% and 94% to 90.4% and 95%. Ultrasound yielded a sensitivity of 83.7% and a specificity of 95.9% in these groups. 11
What I do now
Appendicitis remains a clinical diagnosis. In utilizing clinical prediction rules it is critical to understand their applications and limitations. In the case of the Alvarado score, high scores in adult male populations are well validated. 4 Lower scores and other populations (female and children) require clinical suspicion and often further investigation including imaging. 3,5,10
What this tool has done is change my communication with specialists. In clear cases with high scores >6 I can reduce my clinical findings to a short sentence conveying my concerns and intentions immediately and upfront. 6 In the rapid pace of surgery and the ER I have found this to be a more effective use of time. Several studies have noted that using the Alvarado score in coordination with clinical assessment, as opposed to using the score for definitive diagnosis, may have some utility. 9,12 In regards to lower scores further assessment through observation or further diagnostic/imaging workup is required. 6,10 Not all cases necessitate a knee jerk CT scan. If clinical suspicion and Alvarado score are high enough a discussion with your general surgeon is warranted, as an US may be sufficient. Although ultimately, unless clinically unclear, the decision of imaging and CT vs US will rest with the surgeon on call, as they will be the one’s opening up the abdominal black box.
Looking towards the future there are some studies suggesting the incorporation of imaging and more specifically ultrasound into new scoring systems. 13
References and/or Additional reading
- Alvarado A. A practical score for the early diagnosis of acute appendicitis. Annals of Emergency Medicine. 1986;15(5):557-64(0196-0644) (Request with CPSBC or view UBC) DOI: 1016/S0196-0644(86)80993-3
- Kalan M, Talbot D FAU – Cunliffe,W J., Cunliffe WJ FAU – Rich,A J., Rich AJ. Evaluation of the modified alvarado score in the diagnosis of acute appendicitis: A prospective study. Annals of The Royal College of Surgeons of England. 1994;76(6):418-9(0035-8843) View
- Malik AA, Wani NA. Continuing diagnostic challenge of acute appendicitis: Evaluation through modified alvarado score. (0004-8682) Aust N Z J Surg. 1998 Jul;68(7):504-5. (View with CPSBC or UBC) DOI: 1111/j.1445-2197.1998.tb04811.x
- Pouget-Baudry Y, Mucci S, Eyssartier E, et al. The use of the alvarado score in the management of right lower quadrant abdominal pain in the adult. Journal of Visceral Surgery. 2010;147(2):e40-e44. (View with CPSBC or UBC) DOI: 1016/j.jviscsurg.2010.05.002
- Meltzer AC, Baumann BM FAU – Chen,Esther H., Chen EH FAU – Shofer,Frances S., Shofer FS FAU – Mills,Angela M., Mills AM. Poor sensitivity of a modified alvarado score in adults with suspected appendicitis. Annals of Emergency Medicine. 2013;62(2):126-31(1097-6760 (Electronic); 0196-0644. (View with CPSBC or UBC) DOI: 1016/j.annemergmed.2013.01.021
- Ohle R, O’Reilly F FAU – O’Brien,Kirsty K., O’Brien KK FAU – Fahey,Tom, Fahey T FAU – Dimitrov,Borislav D., Dimitrov BD. The alvarado score for predicting acute appendicitis: A systematic review. BMC Medicine. 2011;9:139(1741-7015) View DOI: 10.1186/1741-7015-9-139
- Ebell MH, Shinholser J. What are the most clinically useful cutoffs for the alvarado and pediatric appendicitis scores? A systematic review. Annals of Emergency Medicine. 2014;64(4):365-372(1097-6760 (Electronic); 0196-0644. (View with CPSBC or UBC) DOI: 1016/j.annemergmed.2014.02.025
- Maguire J, Kulik D, Laupacis A, Kuppermann N, Uleryk E, Parkin P. Clinical prediction rules for children: A systematic review. 2011(128):pp. e666–e677. View DOI: 10.1542/peds.2011-0043
- Kulik DM, Uleryk EM FAU – Maguire,Jonathon L., Maguire JL. Does this child have appendicitis? A systematic review of clinical prediction rules for children with acute abdominal pain. Journal of Clinical Epidemiology. 2013;66(1):95-104(1878-5921 (Electronic); 0895-4356. (View with CPSBC or UBC) DOI: 1016/j.jclinepi.2012.09.004
- McKay R, Shepherd J. The use of the clinical scoring system by alvarado in the decision to perform computed tomography for acute appendicitis in the ED. American Journal of Emergency Medicine. 2007;25(5):489-93(1532-8171 (Electronic); 0735-6757. (View with CPSBC or UBC) DOI: 1016/j.ajem.2006.08.020
- Shogilev DJ, Duus N, Odom SR, Shapiro NI. Diagnosing appendicitis: Evidence-based review of the diagnostic approach in 2014. Western Journal of Emergency Medicine. 2014;15(7):859-71(1936-9018 (Electronic); 1936-900X. View DOI: 10.5811/westjem.2014.9.21568
- Man E, Simonka Z FAU – Varga,Akos, Varga A FAU – Rarosi,Ferenc, Rarosi F FAU – Lazar,Gyorgy, Lazar G. Impact of the alvarado score on the diagnosis of acute appendicitis: Comparing clinical judgment, alvarado score, and a new modified score in suspected appendicitis: A prospective, randomized clinical trial. Surgical Endoscopy. 2014;28(8):2398-405(1432-2218 (Electronic); 0930-2794. (View with CPSBC or UBC) DOI: 10.1007/s00464-014-3488-8
- Debnath J, Ravikumar R, Muralidharan CG, Singh G. Alvarado score: Is it time to develop a clinical-pathological-radiological scoring system for diagnosing acute appendicitis? American Journal of Emergency Medicine. 2015;33(6):839-40.(Electronic); 0735-6757. (View with CPSBC or UBC) DOI: 1016/j.ajem.2015.03.010