liu.seSearch for publications in DiVA
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Structured management of patients with suspected acute appendicitis
Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
2015 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Background. Acute appendicitis (“appendicitis”) is one of the most common abdominal surgical emergencies worldwide. In spite of this, the diagnostic pathways are highly variable across countries, between centres and physicians. This has implications for the use of resources, exposure of patients to ionising radiation and patient outcome. The aim of this thesis is to construct and validate a diagnostic appendicitis score, to evaluate new inflammatory markers for inclusion in the score, and explore the effect of implementing a structured management algorithm for patients with suspected appendicitis. Also, we compare the outcome of management with routine diagnostic imaging versus observation and selective imaging in equivocal cases.

Methods. In study I, the Appendicitis Inflammatory Response (AIR) score was constructed from eight variables with independent diagnostic value (right lower quadrant pain, rebound tenderness or muscular defence, WBC count, proportion of polymorphonuclear granulocytes, CRP, body temperature and vomiting). Its diagnostic properties were evaluated and compared with the Alvarado score. In study II, we performed an external validation and evaluation of novel inflammatory markers for inclusion in the score on patients with suspected appendicitis at two Swedish hospitals. In study III we externally validated and evaluated the impact of an AIR-scorebased algorithm assigning patients to a low or high risk of having appendicitis in an interventional multicentre study involving 25 Swedish hospitals and 3791 patients. In study IV, we compared the efficiency of routine diagnostic imaging with repeated clinical assessment followed by selective imaging in a randomised trial of 1028 patients with equivocal signs of appendicitis, as indicated by an intermediate AIR score, from study III.

Main results. In study I we found that the AIR score could assign 63% of the patients to either a high- or low-risk group of appendicitis with an accuracy of 97%, which compared favourably with the Alvarado score. In study II, the diagnostic properties of the AIR score proved to be  reproducible, but the inclusion of novel inflammatory markers did not improve the diagnostic accuracy. In study III, the AIR-score-based algorithm led to a reduction in negative explorations, operations for nonperforated appendicitis and hospital admissions in the low-risk group and reduced use of imaging in both low- and high-risk groups. In study IV, routine imaging led to more operations for nonperforated appendicitis but had no effect on negative explorations or perforated appendicitis.

Conclusions. The AIR score was found to have promising diagnostic properties that were not improved further with the inclusion of novel inflammatory variables. Structured management of patients with suspected appendicitis according to an AIR-score-based algorithm may improve outcome while reducing hospital admissions and use of imaging. Patients with equivocal signs of appendicitis do not benefit from routine imaging which may lead to an increased detection of, and treatment for, uncomplicated cases of appendicitis that are otherwise allowed to resolve spontaneously.

Place, publisher, year, edition, pages
Linköping: Linköping University Electronic Press, 2015. , 110 p.
Series
Linköping University Medical Dissertations, ISSN 0345-0082 ; 1442
National Category
Clinical Medicine Surgery
Identifiers
URN: urn:nbn:se:liu:diva-113766DOI: 10.3384/diss.diva-113766ISBN: 978-91-7519-137-9 (print)OAI: oai:DiVA.org:liu-113766DiVA: diva2:784649
Public defence
2015-03-06, Originalet, Qulturum, Länssjukhuset Ryhov, Jönköping, 13:00
Opponent
Supervisors
Funder
Futurum - Academy for Health and Care, Jönköping County Council, SwedenMedical Research Council of Southeast Sweden (FORSS)
Available from: 2015-01-30 Created: 2015-01-30 Last updated: 2015-11-16Bibliographically approved
List of papers
1. The appendicitis inflammatory response score: A tool for the diagnosis of acute appendicitis that outperforms the Alvarado score
Open this publication in new window or tab >>The appendicitis inflammatory response score: A tool for the diagnosis of acute appendicitis that outperforms the Alvarado score
2008 (English)In: World Journal of Surgery, ISSN 0364-2313, E-ISSN 1432-2323, Vol. 32, no 8, 1843-1849 p.Article in journal (Refereed) Published
Abstract [en]

Background: The clinical diagnosis of appendicitis is a subjective synthesis of information from variables with ill-defined diagnostic value. This process could be improved by using a scoring system that includes objective variables that reflect the inflammatory response. This study describes the construction and evaluation of a new clinical appendicitis score. Methods: Data were collected prospectively from 545 patients admitted for suspected appendicitis at four hospitals. The score was constructed from eight variables with independent diagnostic value (right-lower-quadrant pain, rebound tenderness, muscular defense, WBC count, proportion neutrophils, CRP, body temperature, and vomiting) in 316 randomly selected patients and evaluated on the remaining 229 patients. Ordered logistic regression was used to obtain a high discriminating power with focus on advanced appendicitis. Diagnostic performance was compared with the Alvarado score. Results: The ROC area of the new score was 0.97 for advanced appendicitis and 0.93 for all appendicitis compared with 0.92 (p = 0.0027) and 0.88 (p = 0.0007), respectively, for the Alvarado score. Sixty-three percent of the patients were classified into the low- or high-probability group with an accuracy of 97.2%, leaving 37% for further investigation. Seventy-three percent of the nonappendicitis patients, 67% of the advanced appendicitis, and 37% of all appendicitis patients were correctly classified into the low- and high-probability zone, respectively. Conclusion: This simple clinical score can correctly classify the majority of patients with suspected appendicitis, leaving the need for diagnostic imaging or diagnostic laparoscopy to the smaller group of patients with an indeterminate scoring result. © 2008 Société Internationale de Chirurgie.

National Category
Medical and Health Sciences
Identifiers
urn:nbn:se:liu:diva-45600 (URN)10.1007/s00268-008-9649-y (DOI)
Available from: 2009-10-11 Created: 2009-10-11 Last updated: 2017-12-13
2. Can New Inflammatory Markers Improve the Diagnosis of Acute Appendicitis?
Open this publication in new window or tab >>Can New Inflammatory Markers Improve the Diagnosis of Acute Appendicitis?
Show others...
2014 (English)In: World Journal of Surgery, ISSN 0364-2313, E-ISSN 1432-2323, Vol. 38, no 11, 2777-2783 p.Article in journal (Refereed) Published
Abstract [en]

The diagnosis of appendicitis is difficult and resource consuming. New inflammatory markers have been proposed for the diagnosis of appendicitis, but their utility in combination with traditional diagnostic variables has not been tested. Our objective is to explore the potential of new inflammatory markers for improving the diagnosis of appendicitis. The diagnostic properties of the six most promising out of 21 new inflammatory markers (interleukin [IL]-6, chemokine ligand [CXCL]-8, chemokine C-C motif ligand [CCL]-2, serum amyloid A [SAA], matrix metalloproteinase [MMP]-9, and myeloperoxidase [MPO]) were compared with traditional diagnostic variables included in the Appendicitis Inflammatory Response (AIR) score (right iliac fossa pain, vomiting, rebound tenderness, guarding, white blood cell [WBC] count, proportion neutrophils, C-reactive protein and body temperature) in 432 patients with suspected appendicitis by uni- and multivariable regression models. Of the new inflammatory variables, SAA, MPO, and MMP9 were the strongest discriminators for all appendicitis (receiver operating characteristics [ROC] 0.71) and SAA was the strongest discriminator for advanced appendicitis (ROC 0.80) compared with defence or rebound tenderness, which were the strongest traditional discriminators for all appendicitis (ROC 0.84) and the WBC count for advanced appendicitis (ROC 0.89). CCL2 was the strongest independent discriminator beside the AIR score variables in a multivariable model. The AIR score had an ROC area of 0.91 and could correctly classify 58.3 % of the patients, with an accuracy of 92.9 %. This was not improved by inclusion of the new inflammatory markers. The conventional diagnostic variables for appendicitis, as combined in the AIR score, is an efficient screening instrument for classifying patients as low-, indeterminate-, or high-risk for appendicitis. The addition of the new inflammatory variables did not improve diagnostic performance further.

Place, publisher, year, edition, pages
Springer, 2014
National Category
Clinical Medicine
Identifiers
urn:nbn:se:liu:diva-112174 (URN)10.1007/s00268-014-2708-7 (DOI)000343048900006 ()25099684 (PubMedID)
Note

Funding Agencies|Jonkoping County Research Council; Research Council of South-Eastern Sweden (FORSS); Futurum- Academy of Health Care, Jonkoping County Council, Jonkoping, Sweden

Available from: 2014-11-18 Created: 2014-11-18 Last updated: 2017-12-05Bibliographically approved
3. Structured Management of Patients with Suspected Acute Appendicitis Using a Clinical Score and Selective Imaging (STRAPPSCORE)
Open this publication in new window or tab >>Structured Management of Patients with Suspected Acute Appendicitis Using a Clinical Score and Selective Imaging (STRAPPSCORE)
2015 (English)Manuscript (preprint) (Other academic)
Abstract [en]

Background

The management of patients with suspected appendicitis is highly variable with implications for the rate of diagnostic errors, unnecessary admissions and resource consumption. We hypothesise that a structured management algorithm based on the Appendicitis Inflammatory Response (AIR) score can improve diagnostic accuracy, limit the use of diagnostic imaging, and reduce the number of hospital admissions for patients with suspected appendicitis.

Methods

Prospective interventional multicentre study. Patients at 25 Swedish hospitals over the age of five, presenting with suspected appendicitis at the emergency department were considered for inclusion. After an initial period of routine management and registration of the AIR score parameters (baseline period), an AIR-score-based management algorithm was implemented (intervention period). The study analyses the discriminating capacity and predictive value of the AIR score and the impact of implementing the AIR-score-based algorithm.

Results

In total, 3791 patients were included. Advanced appendicitis is unlikely at an AIR score <5 points (sensitivity 0.96), and appendicitis is likely at an AIR score >8 (specificity 0.98). The implementation of the AIR-score-based algorithm resulted in fewer negative explorations and operations for phlegmonous appendicitis (1.6% vs 3.4%, p=0.019 and 5.5% vs 9.4%, p=0.003, respectively), a reduction in admissions to hospital and use of imaging (29.5% vs 42.8%, p<0.001 and 19.2% vs 34.5%, respectively), and no difference with regard to advanced appendicitis in the low-risk group, and a decrease in the use of diagnostic imaging in the high-risk group (38.5% vs 53.1%, p=0.021).

Conclusions

The AIR score has high discriminating capacity. Implementing an AIR-score-based algorithm increased diagnostic accuracy and lowered the use of diagnostic imaging and in-hospital observation.

National Category
Clinical Medicine
Identifiers
urn:nbn:se:liu:diva-113764 (URN)
Funder
Futurum - Academy for Health and Care, Jönköping County Council, SwedenMedical Research Council of Southeast Sweden (FORSS)
Available from: 2015-01-30 Created: 2015-01-30 Last updated: 2015-01-30Bibliographically approved
4. Routine versus selective diagnostic imaging in patients with intermediate probability of acute appendicitis: A randomised controlled multicentre study
Open this publication in new window or tab >>Routine versus selective diagnostic imaging in patients with intermediate probability of acute appendicitis: A randomised controlled multicentre study
2015 (English)Manuscript (preprint) (Other academic)
Abstract [en]

Background

Diagnostic imaging is increasingly used in patients with suspected appendicitis, with increased costs and concerns about exposure to ionising radiation. Indications suggest that routine imaging is associated with a higher detection rate and treatment of potentially resolving appendicitis. The efficiency of routine imaging compared with in-hospital observation and selective imaging is not well studied.

Methods

The proportions of negative appendectomy and treatments for appendicitis are studied in 1068 patients with intermediate suspicion of appendicitis, indicated by an Appendicitis Inflammatory Response (AIR) score sum of five to eight points, randomly allocated by opaque sealed envelopes to early routine diagnostic imaging (Imaging group, n=543) or re-assessment after 4–8 hours inhospital observation followed by selective diagnostic imaging (Observation group, n=525). Some 21 hospitals in Sweden participated in this multicentre study.

Findings

The Imaging and Observation groups had the same proportion of negative appendectomies (6·5% in both, difference 0·03%, CI –3·0%–3·1%, p=0·98) but routine imaging was associated with an increased proportion of patients treated for appendicitis (53·4% vs 46·3%, difference  7·1%, CI 1·0–13·2%, p=0·020). As secondary outcomes, the Imaging group had shorter time to surgery (median 13·7 hours vs 15·5 hours, p<0·01), but no difference in admissions, number of perforations or length of hospital stay.

Interpretation

Patients with suspected appendicitis and equivocal clinical findings do not benefit from early routine diagnostic imaging compared with re-assessment after observation and selective imaging. The latter is associated with fewer operations for non-perforated appendicitis which supports the hypothesis of resolving appendicitis.

National Category
Clinical Medicine
Identifiers
urn:nbn:se:liu:diva-113765 (URN)
Funder
Futurum - Academy for Health and Care, Jönköping County Council, SwedenMedical Research Council of Southeast Sweden (FORSS)
Available from: 2015-01-30 Created: 2015-01-30 Last updated: 2015-01-30Bibliographically approved

Open Access in DiVA

fulltext(2482 kB)441 downloads
File information
File name FULLTEXT01.pdfFile size 2482 kBChecksum SHA-512
6c2544d2dd3664217fc0dfa825ca80ee731e8a44ca8926d12913bfb2155eef5d57947d81637f062fbb14dc4e8fa7b41d5838719c775714bc82078336115cd6d8
Type fulltextMimetype application/pdf
omslag(2881 kB)49 downloads
File information
File name COVER01.pdfFile size 2881 kBChecksum SHA-512
c392e42c107f24d50471b47d7ba2c06da5925a782d9852d4234d865ccea2e5ccb15e3ae174ee577b9e254e818a62d109bca01568a95511ace7e67d66652ac9f2
Type coverMimetype application/pdf

Other links

Publisher's full text

Authority records BETA

Andersson, Manne

Search in DiVA

By author/editor
Andersson, Manne
By organisation
Department of Clinical and Experimental MedicineFaculty of Health Sciences
Clinical MedicineSurgery

Search outside of DiVA

GoogleGoogle Scholar
Total: 441 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

doi
isbn
urn-nbn

Altmetric score

doi
isbn
urn-nbn
Total: 3273 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf