Incidence and case fatality rates for acute appendicitis in California. A population-based study of the effects of age

Swedish national guidelines for diagnosis and management of acute appendicitis in adults and children

BACKGROUND

Acute appendicitis is one of the most common causes of acute abdominal pain. Differences in the management of this large group of patients has important consequences for the patients and the healthcare system. Controversies regarding the understanding of the natural course of the disease, the utility of new diagnostic methods, and alternative treatments have lead to large variations in practice patterns between centres. These national guidelines present evidence-based recommendations aiming at a uniform, safe and cost-efficient management of this large group of patients.

METHOD

A working group of six experts with broad clinical and research experience was formed. Additional expertise from outside was consulted during the process. A national survey revealed significant variations in the management of patients with suspicion of appendicitis. The evidence provided in published guidelines and reviews were extracted and systematically graded, according to the GRADE methodology. This was supplemented by additional more recent and more directed search of the literature. Patients treated for appendicitis were involved through interviews. The guidelines were reviewed by external experts before the final version was determined.

RESULTS

The guidelines cover an extensive number of issues: pathology, epidemiology, aetiology, natural history, clinical and laboratory diagnosis, diagnostic scoring systems, diagnostic imaging, treatment, nursing care, follow-up, quality registers and quality indicators, among others. Special considerations related to children and pregnant women are covered.

CONCLUSION

These national guidelines present an extensive and thorough review of the current knowledge base related to appendicitis, and provide up-to-date evidence-based recommendations for the management of this large group of patients.

Spontaneous Resolution of Uncomplicated Appendicitis may Explain Increase in Proportion of Complicated Appendicitis During Covid-19 Pandemic: a Systematic Review and Meta-analysis

BACKGROUND

Reports of an increased proportion of complicated appendicitis during the Covid-19 pandemic suggest a worse outcome due to delay secondary to the restrained access to health care, but may be explained by a concomitant decrease in uncomplicated appendicitis. We analyze the impact of the pandemic on the incidences of complicated and uncomplicated appendicitis.

METHOD

We did a systematic literature search in the PubMed, Embase and Web Of Science databases on December 21, 2022 with the search terms (appendicitis OR appendectomy) AND ("COVID" OR SARS-Cov2 OR "coronavirus"). Studies reporting the number of complicated and uncomplicated appendicitis during identical calendar periods in 2020 and the pre-pandemic year(s) were included. Reports with indications suggesting a change in how the patients were diagnosed and managed between the two periods were excluded. No protocol was prepared in advance. We did random effects meta-analysis of the change in proportion of complicated appendicitis, expressed as the risk ratio (RR), and of the change in number of patients with complicated and uncomplicated appendicitis during the pandemic compared with pre-pandemic periods, expressed as the incidence ratio (IR). We did separate analyses for studies based on single- and multi-center and regional data, age-categories and prehospital delay.

RESULTS

The meta-analysis of 100,059 patients in 63 reports from 25 countries shows an increase in the proportion of complicated appendicitis during the pandemic period (RR 1.39, 95% confidence interval (95% CI 1.25, 1.53). This was mainly explained by a decreased incidence of uncomplicated appendicitis (incidence ratio (IR) 0.66, 95% CI 0.59, 0.73). No increase in complicated appendicitis was seen in multi-center and regional reports combined (IR 0.98, 95% CI 0.90, 1.07).

CONCLUSION

The increased proportion of complicated appendicitis during Covid-19 is explained by a decrease in the incidence of uncomplicated appendicitis, whereas the incidence of complicated appendicitis remained stable. This result is more evident in the multi-center and regional based reports. This suggests an increase in spontaneously resolving appendicitis due to the restrained access to health care. This has important principal implications for the management of patients with suspected appendicitis.

Acute appendicitis manifests as two microbiome state types with oral pathogens influencing severity

Mounting evidence suggests that acute appendicitis (AA) is not one but two diseases: complicated appendicitis, which is associated with necrosis leading to perforation or periappendicular abscess, and uncomplicated appendicitis, which does not necessarily result in perforation. Even though AA is the most frequent cause of surgery from abdominal pain, little is known about the origins and etiopathogenesis of this disease, much less regarding the different disease types. In this study, we investigated the microbiome (inter-domain amplicon and metagenome sequencing) of samples from the appendix, rectum and peritoneum of 60 children and adolescents with AA to assess the composition and potential function of bacteria, archaea and fungi. The analysis of the appendix microbial community revealed a shift depending on the severity of the AA. This shift was reflected by two major community state types that represented the complicated and uncomplicated cases. We could demonstrate that complicated, but not uncomplicated, appendicitis is associated with a significant local expansion of oral, bacterial pathogens in the appendix, most strongly influenced by necrotizing Fusobacterium spp., Porphyromonas and Parvimonas. Uncomplicated appendicitis, however, was characterized by gut-associated microbiomes. Our findings support the hypothesis that two disease types exist in AA, which cannot be distinguished beyond doubt using standard clinical characterization methods or by analysis of the patient's rectal microbiome. An advanced microbiome diagnosis, however, could improve non-surgical treatment of uncomplicated AA.

Risks of complicated acute appendicitis in patients with psychiatric disorders

BACKGROUND

Acute appendicitis often presents with vague abdominal pain, which fosters diagnostic challenges to clinicians regarding early detection and proper intervention. This is even more problematic with individuals with severe psychiatric disorders who have reduced sensitivity to pain due to long-term or excessive medication use or disturbed bodily sensation perceptions. This study aimed to determine whether psychiatric disorder, psychotropic prescription, and treatment compliance increase the risks of complicated acute appendicitis.

METHODS

The diagnosis records of acute appendicitis from four university hospitals in Korea were investigated from 2002 to 2020. A total of 47,500 acute appendicitis-affected participants were divided into groups with complicated and uncomplicated appendicitis to determine whether any of the groups had more cases of psychiatric disorder diagnoses. Further, the ratio of complicated compared to uncomplicated appendicitis in the mentally ill group was calculated regarding psychotropic dose, prescription duration, and treatment compliance.

RESULTS

After adjusting for age and sex, presence of psychotic disorder (odds ratio [OR]: 1.951; 95% confidence interval [CI]: 1.218-3.125), and bipolar disorder (OR: 2.323; 95% CI: 1.194-4.520) was associated with a higher risk of having complicated appendicitis compared with absence of psychiatric disorders. Patients who are taking high-daily-dose antipsychotics, regardless of prescription duration, show high complicated appendicitis risks; High-dose antipsychotics for < 1 year (OR: 1.896, 95% CI: 1.077-3.338), high-dose antipsychotics for 1-5 years (OR: 1.930, 95% CI: 1.144-3.256). Poor psychiatric outpatient compliance was associated with a high risk of complicated appendicitis (OR: 1.664, 95% CI: 1.014-2.732).

CONCLUSIONS

This study revealed a close relationship in the possibility of complicated appendicitis in patients with severe psychiatric disorders, including psychotic and bipolar disorders. The effect on complicated appendicitis was more remarkable by the psychiatric disease entity itself than by psychotropic prescription patterns. Good treatment compliance and regular visit may reduce the morbidity of complicated appendicitis in patients with psychiatric disorders.

A novel Appendicitis TriMOdal prediction Score (ATMOS) for acute appendicitis in pregnancy: a retrospective observational study

Several scoring systems exist for the management of acute appendicitis (AA) during pregnancy. However, the systems are based on the nonpregnant adult population. The aim of this study was to create a highly accurate scoring system that can be applied to pregnant women and to compare it to the most commonly used scores in general population and pregnant women. The creation and subsequent implementation of a highly accurate score system could shorten the diagnostic period and minimize the use of (ionizing) diagnostic imaging allowing the selection of the best treatment approach in pregnant patients with acute appendicitis. A single-center, retrospective cohort observational study was conducted at the University Hospital Centre Zagreb, Zagreb, Croatia. Data were extracted from medical records of pregnant patients with suspected AA from January 2010 to December 2020. A total of 59 pregnant patients diagnosed with AA during pregnancy were identified, 41 were treated surgically, and 18 had non-surgical management. The main objective of our study was the detection of predictive factors of AA during pregnancy. Anorexia, pain migration to the right lower quadrant, rebound pain, axillary temperature over 37.3 °C, CRP/platelet ratio > 0.0422, neutrophil/lymphocyte ratio > 7.182, and ultrasonic signs of AA were scored. Scoring in Appendicitis TriMOdal Score (ATMOS) consists of positive clinical parameter, each bringing 1 point and other parameters mentioned above that bring 2 points each. The score ranges from 0 to 10. Our model of ATMOS yields a high area under the receiver-operating characteristic curve of 0.963. The positive likelihood ratio is 9.97 (95% CI 2.64-38.00), and the negative likelihood ratio is 0.1 (95% CI 0.03-0.31), meaning that 94% of cases with ATMOS > 4 have AA, while less than 13% with an ATMOS ≤ 4 have the diagnosis of AA. The potential of ATMOS differentiating AA during pregnancy was demonstrated. Future prospective, randomized trials are needed to evaluate its accuracy and whether it should be used instead of Alvarado or Tzanakis scores in clinical decision-making.Trial registration number ClinicalTrials.gov-NCT05202483. Date of registration: January 21, 2022.

Demonstration of a new entity of non-perforated appendicitis through studying cluster of appendicitis

Differential diagnosis and management for perforated appendicitis and non-perforated appendicitis are current hot topics. The aim of this study is to demonstrate a new entity of non-perforated appendicitis, “acute hemorrhagic appendicitis” through studying cluster of acute appendicitis among Tibetan students at a high school in central China. Over the 11-year period, there were 120 patients with more female patients (102 of 499, 20.4%) than male patients (18 of 474, 3.8%) among 973 Tibetan students. 117 patients’ clinical data were available. Clinical manifestations were identical to classic appendicitis. However, axilla temperature, white blood cell counts and neutrophil level were elevated mildly in 12 (10.3%), 19 (16.2%) and 12 (10.3%) patients respectively. Pathologically, the resected appendices exhibited focal or diffuse hemorrhages in mucosa and/or submucosa, and infiltration by eosinophil and by lymphocytes. No patients had perforated appendicitis. The median time from the onset to surgery was 3 days (IQR, 2–4). All patients were discharged with full recovery. In conclusion, “acute hemorrhagic appendicitis” represented a new entity of non-perforated appendicitis with unique cause and pathogenesis, which might be treated with antibiotics alone or self-limited. Studying the cluster is a reliable method to find new entity of appendicitis.

Nationwide paediatric cohort study of a protective association between allergy and complicated appendicitis

BACKGROUND

In a nationwide cohort the potentially protective association between allergy and complicated appendicitis was analysed, and the influence of seasonal antigens, antihistamine treatment, and timing of allergy onset assessed.

METHODS

Some 1 112 571 children born between 2000 and 2010 were followed from birth until the end of 2014. A cross-sectional analysis of appendicitis cases, with comparison of allergic versus non-allergic children for absolute risk and odds of complicated appendicitis was first undertaken. This was followed by a longitudinal analysis of children with allergy and matched controls who had never had an allergy, for incidence rate and hazard of subsequent complicated or simple appendicitis.

RESULTS

Of all children, 20.4 per cent developed allergy and 0.6 per cent had appendicitis during follow-up. Among children with appendicitis, complicated appendicitis was more common among non-allergic children (18.9 per cent, 948 of 5016) than allergic children (12.8 per cent, 173 of 1351) (P < 0.001), and allergic children had a lower adjusted odds of complicated appendicitis (adjusted odds ratio (OR) 0.80, 95 per cent c.i. 0.67 to 0.96; P = 0.021). The risk of complicated appendicitis among children with manifest allergy was reduced by one-third in the longitudinal analysis (incidence rate 0.13 versus 0.20 per 1000 person-years; hazard ratio (HR) 0.68, 95 per cent c.i. 0.58 to 0.81; P < 0.001), whereas the risk of simple appendicitis remained unchanged (incidence rate 0.91 versus 0.91; HR 1.00, 0.94 to 1.07; P = 0.932). Seasonal antigen exposure was a protective factor (adjusted OR 0.82, 0.71 to 0.94; P = 0.004) and ongoing antihistamine medication a risk factor (adjusted OR 2.28, 1.21 to 4.28; P = 0.012).

CONCLUSION

Children with allergy have a lower risk of complicated appendicitis, but the same overall risk of simple appendicitis. Seasonal antigen exposure reduced, and antihistamine treatment increased, the risk of complicated disease.

Changes in Incidence and Management of Acute Appendicitis in Children-A Population-Based Study in the Period 2000-2015

INTRODUCTION

 Recent studies suggest that the epidemiology and management of appendicitis have changed during the last decades. The purpose of this population-based study was to examine this in the pediatric population in Denmark.

MATERIALS AND METHODS

 Data were retrieved from the Danish National Patient Registry, the Danish Civil Registration System, and the Statbank Denmark. Patients aged 0 to 17 years diagnosed with appendicitis and appendectomized during the period 2000 to 2015 were included. The primary outcome was the annual incidences of appendicitis. Secondary outcomes were the annual percent of patients with appendicitis having a laparoscopic appendectomy, delay from admission to surgery, length of postoperative hospital stay, and 30-day postoperative mortality.

RESULTS

 A total of 24,046 pediatric cases of appendicitis were identified. The annual incidence steadily declined until 2008 (-29%, all ages) and then remained stable. The surgical approach of choice changed from being open appendectomy in 2000 (97%) to laparoscopic appendectomy in 2015 (94%). Simultaneously, the duration of postoperative hospital stay declined from 41 hours (median) to 17 hours. Delay from admission until surgery did not change during the period. Only one child died within the 30-day postoperative period.

CONCLUSION

 In accordance with other recent studies from Western countries, we found significant changes in the incidence of acute appendicitis including a decline in all age groups except those below 5 years of age, a shift toward laparoscopic appendectomy, and decreasing time spent in the hospital during the years 2000 to 2015.

Prevalence of Postoperative Unfavorable Outcome and Associated Factors in Patients with Appendicitis: A Cross-Sectional Study

Purpose

Appendicitis is surgical emergency that might need removal of the inflamed appendix. Unless treated, appendicular abscess, perforation, and even death might be the unfavorable outcomes. Hence, this study was aimed to investigate the unfavorable outcomes and associated factors among appendicitis operated patients.

Patients and Methods

A total of 300 patients who operated for appendicitis from September 1 2019 to August 30 2020 were studied using a retrospective cross-sectional study. Data were collected by using a checklist. Epi-data and SPSS version 25 were used for data entry and analysis, respectively. Binary logistic regression model was used to identify independent factors. A p<0.05 was used to set the statistical significance of factors.

Results

Among 300 patients who were operated for acute appendicitis, 36 (12%) developed unfavorable outcomes. Though one death because of sepsis was recorded, wound infection was the main postoperative disorder. Female (AOR=0.49; 95% CI: 0.13-0.074), living outside the hospital setting (AOR= 0.49; 95% CI: 0.13-0.074), duration of illness before arrival at the hospital (1-3 days (AOR= 1.67; 95% CI: 1.34-8.37) and ≥4 days (AOR=5.38; 95% CI: 1.63-7.69)), more than 3 days hospital stay (AOR= 3.21; 95% CI: 2.06-8.10), and mass in the right lower quadrant (AOR= 6.01; 95% CI: 2.11-14.50) were the independent predictors of unfavorable outcomes of appendicitis treatment.

Conclusion

In this study, unfavorable outcome of acute appendicitis was high. More than one-tenth of appendicitis cases developed unfavorable outcomes. Living outside the hospital setting area, long duration of illness before arrival at the Hospital, more than 3 days hospital stay, and mass in the right lower quadrant were the risk factors, while females were less likely to have unfavorable outcomes of appendicitis. Therefore, closely working with patients who have abdominal pain and increasing their awareness about acute appendicitis will improve the operation outcome.

Association of Neighborhood Socioeconomic Disadvantage With Complicated Appendicitis in Children

BACKGROUND

Lower socioeconomic status (SES) is linked to poorer outcomes for a variety of health conditions in children, potentially through delay in accessing care. The objective of this study was to measure the association between SES and delay in surgical care as marked by presentation with complicated appendicitis (CA).

METHODS

Children treated for acute appendicitis between 2015-2019 at a large academic children's hospital were reviewed. Patient home addresses were used to calculate travel time to the children's hospital and to determine Area Deprivation Index (ADI), a neighborhood-level SES marker. Multivariable logistic regression models were used to compare the likelihood of CA across ADI while adjusting for confounders.

RESULTS

Of 1,697 children with acute appendicitis, 38.8% had CA. Compared to those with uncomplicated disease, children with CA were younger, lived farther from the children's hospital, and were more likely to have Medicaid insurance and have ED visits in the 30 days preceding diagnosis. Children with CA disproportionately came from disadvantaged neighborhoods (P < 0.007), with 32% from the two most disadvantaged ADI deciles. The odds of CA rose 5% per ADI decile-increase (adjusted odds ratio [aOR] 1.05, 95%CI 1.01-1.09, P = 0.02). Younger age and >60-min travel time were also associated with CA. Association between ADI and CA remained among younger (<10 y) children (aOR 1.07, 95%CI 1.00-1.15, P = 0.048) and those living closer (<30 min) to the hospital (aOR 1.06, 95%CI 1.01-1.11, p=0.02).

CONCLUSIONS

ADI is associated with CA among children, suggesting ADI may be a valuable marker of difficulty accessing surgical care among disadvantaged children.

Where did the patients go? Changes in acute appendicitis presentation and severity of illness during the coronavirus disease 2019 pandemic: A retrospective cohort study

BACKGROUND

The coronavirus disease 2019 pandemic restricted movement of individuals and altered provision of health care, abruptly transforming health care-use behaviors. It serves as a natural experiment to explore changes in presentations for surgical diseases including acute appendicitis. The objective was to determine if the pandemic was associated with changes in incidence of acute appendicitis compared to a historical control and to determine if there were associated changes in disease severity.

METHODS

The study is a retrospective, multicenter cohort study of adults (N = 956) presenting with appendicitis in nonpandemic versus pandemic time periods (December 1, 2019-March 10, 2020 versus March 11, 2020-May 16, 2020). Corresponding time periods in 2018 and 2019 composed the historical control. Primary outcome was mean biweekly counts of all appendicitis presentations, then stratified by complicated (n = 209) and uncomplicated (n = 747) disease. Trends in presentations were compared using difference-in-differences methodology. Changes in odds of presenting with complicated disease were assessed via clustered multivariable logistic regression.

RESULTS

There was a 29% decrease in mean biweekly appendicitis presentations from 5.4 to 3.8 (rate ratio = 0.71 [0.51, 0.98]) after the pandemic declaration, with a significant difference in differences compared with historical control (P = .003). Stratified by severity, the decrease was significant for uncomplicated appendicitis (rate ratio = 0.65 [95% confidence interval 0.47-0.91]) when compared with historical control (P = .03) but not for complicated appendicitis (rate ratio = 0.89 [95% confidence interval 0.52-1.52]); (P = .49). The odds of presenting with complicated disease did not change (adjusted odds ratio 1.36 [95% confidence interval 0.83-2.25]).

CONCLUSION

The pandemic was associated with decreased incidence of uncomplicated appendicitis without an accompanying increase in complicated disease. Changes in individual health care-use behaviors may underlie these differences, suggesting that some cases of uncomplicated appendicitis may resolve without progression to complicated disease.

Geographic Association Between Incidence of Acute Appendicitis and Socioeconomic Status

Importance

Some studies based on proportions of patients with perforated appendicitis (PA) among all patients with acute appendicitis (AA) have found an association between socioeconomic status (SES) and risk of perforation. A potential limitation is their use of proportions, which assumes that incidence of AA is evenly distributed across populations at risk. This assumption may be invalid, and SES may have a more complex association with both AA and PA.

Objective

To generate population-based incidences of AA and PA and to examine geographic patterns of incidence alongside geographic patterns of SES.

Design, Setting, and Participants

Retrospective study of data from Washington's Comprehensive Hospital Abstract Reporting System and the 2010 US census. Geographic methods were used to identify patterns of age- and sex-standardized incidence in Washington State between 2008 and 2012. The study included all patients discharged with International Classification of Diseases, Ninth Revision codes for AA or PA. Data were analyzed between November 2016 and December 2018.

Exposures

Location of primary residence.

Main Outcomes and Measures

Age- and sex-standardized incidence for AA and PA was generated for each census tract (CT). Global spatial autocorrelation was examined using Moran index (0.0 = completely random incidence; 1.0 = fully dependent on location). Clusters of low-incidence CTs (cold spots) and high-incidence CTs (hot spots) were identified for AA. Census-based SES data were aggregated for hot spots and cold spots and then compared.

Results

Statewide, over the 5-year study period, there were 35 730 patients with AA (including 9780 cases of PA), of whom 16 574 were women (46.4%). Median age of the cohort was 29 years (IQR, 16-48 years). Statewide incidence of AA and PA was 106 and 29 per 100 000 person-years (PY), respectively. Crude incidence was higher within the male population and peaked at age 10 to 19 years. Age- and sex-standardized incidence of AA demonstrated significant positive spatial autocorrelation (Moran index, 0.30; P < .001), but autocorrelation for PA was only half as strong (0.16; P < .001). Median incidence of AA was 118.1 per 100 000 PY among hot spots vs 86.2 per 100 000 PY among cold spots (P < .001). Socioeconomic status was higher in cold spots vs hot spots: mean proportion of college-educated adults was 56% vs 26% (P < .001), and mean per capita income was $44 691 vs $30 027 (P < .001).

Conclusions and Relevance

Age- and sex-standardized incidence of appendicitis is not randomly distributed across geographic subunits, and geographic clustering of AA is twice as strong as PA. Socioeconomic advantages, such as higher income and secondary education, are strongly associated with lower incidence of AA. These findings challenge conventional views that AA occurs randomly and has no predisposing characteristics beyond age/sex. Socioeconomic status, and likely other geographically circumscribed factors, are associated with incidence of AA.

The significant impact of age on the clinical outcomes of laparoscopic appendectomy: Results from the Polish Laparoscopic Appendectomy multicenter large cohort study

Acute appendicitis (AA) is the most common surgical emergency and can occur at any age. Nearly all of the studies comparing outcomes of appendectomy between younger and older patients set cut-off point at 65 years. In this multicenter observational study, we aimed to compare laparoscopic appendectomy for AA in various groups of patients with particular interest in the elderly and very elderly in comparison to younger adults.Our multicenter observational study of 18 surgical units assessed the outcomes of 4618 laparoscopic appendectomies for AA. Patients were divided in 4 groups according to their age: Group 1-<40 years old; Group 2-between 40 and 64 years old; Group 3-between 65 and 74 years old; and Group 4-75 years old or older. Groups were compared in terms of peri- and postoperative outcomes.The ratio of complicated appendicitis grew with age (20.97% vs 37.50% vs 43.97% vs 56.84%, P < .001). Similarly, elderly patients more frequently suffered from perioperative complications (5.06% vs 9.3% vs 10.88% vs 13.68%, P < .001) and had the longest median length of stay (3 [Interquartile Range (IQR) 2-4] vs 3 [IQR 3-5], vs 4 [IQR 3-5], vs 5 [IQR 3-6], P < .001) as well as the rate of patients with prolonged length of hospital stay (LOS) >8 days. Logistic regression models comparing perioperative results of each of the 3 oldest groups compared with the youngest one showed significant differences in odds ratios of symptoms lasting >48 hours, presence of complicated appendicitis, perioperative morbidity, conversion rate, prolonged LOS (>8 days).The findings of this study confirm that the outcomes of laparoscopic approach to AA in different age groups are not the same regarding outcomes and the clinical picture. Older patients are at high risk both in the preoperative, intraoperative, and postoperative period. The differences are visible already at the age of 40 years old. Since delayed diagnosis and postponed surgery result in the development of complicated appendicitis, more effort should be placed in improving treatment patterns for the elderly and their clinical outcome.

MRI for Pediatric Appendicitis in an Adult-Focused General Hospital: A Clinical Effectiveness Study-Challenges and Lessons Learned

OBJECTIVE

The objective of our study was to determine the feasibility and accuracy of MRI for pediatric appendicitis in an adult-predominant general hospital setting where non-pediatric-trained radiologists routinely interpret the studies.

MATERIALS AND METHODS

MRI was performed in pediatric patients with equivocal ultrasound (US) findings and persistent clinical concern for appendicitis. Neither IV contrast material nor a sedative was administered. Our MRI protocol evolved early during the study period, quickly settling on three sequences (total scanning time, 11 minutes). The clinical reference standard for statistical analysis was appendicitis diagnosed on operative or pathology report; 95% Clopper-Pearson CIs were calculated.

RESULTS

Between 2012 and 2016, 528 pediatric patients (mean age, 9.9 years; age range, 1-17 years) underwent MRI after US evaluation yielded equivocal findings: 10.4% (55/528) of patients were found to have surgically proven or pathologically proven appendicitis. Sensitivity and specificity of MRI for appendicitis were 96.4% and 98.9%, respectively. Positive and negative predictive values were 91.2% and 99.6%. A normal appendix and abnormalities not involving the appendix were identified on MRI in 21.6% (114/528) of patients.

CONCLUSION

Our data show that unenhanced MRI for suspected appendicitis in pediatric patients is clinically effective when performed in a nonpediatric hospital setting with nonpediatric radiologists, emergency physicians, and surgeons.

Effects of Timing of Appendectomy on the Risks of Perforation and Postoperative Complications of Acute Appendicitis

BACKGROUND

It is generally believed that appendectomy should be performed immediately to prevent perforation and complications. Therefore, our objectives were to investigate the effect of timing of appendectomy on the incidence of perforation and complications.

METHODS

We retrospectively reviewed the medical records of patients who underwent laparoscopic appendectomy between January 2014 and June 2015. The time from symptom onset to appendectomy was categorized into three periods: time from symptom onset to hospital admission (symptomatic time), time from admission to appendectomy (hospitalization time), and time from symptom onset to appendectomy [symptomatic period + hospitalization period (overall time)]. Multivariable analyses were performed to identify independent factors associated with perforation and complications.

RESULTS

A total of 1753 patients were included in the present study. Perforation occurred in 28.2% of patients, and postoperative complications occurred in 10.0% of patients. Multivariable analysis showed that BT > 38 °C (P = 0.006), WBC count >13,000 cells/µl (P = 0.02), neutrophil ratio >80% (P < 0.001), and symptomatic time >24 h (P < 0.001) were independent factors of appendiceal perforation, while the neutrophil ratio >80% (P < 0.001) and symptomatic time >48 h (P = 0.003) were independently associated with complications.

CONCLUSIONS

The present study showed that the symptomatic time and overall time were significantly associated with perforation and complications, whereas hospitalization time was not associated with either perforation or complications.

Meaningful standard of reference for appendiceal perforation: pathology, surgery, or both?

Purpose

This retrospective study was aimed to determine if appendiceal perforation identified pathologically but not surgically is clinically meaningful.

Methods

The study consists of 2 parts. First, we reviewed 74 studies addressing appendiceal perforation published in 2012 and 2013. Second, in a cross-sectional study, we classified 1,438 adolescents and adults (mean age, 29.3 ± 8.4 years; 785 men) with confirmed appendicitis as “nonperforation” (n = 1,083, group 1), “pathologically-identified perforation” (n = 55, group 2), “surgically-identified perforation” (n = 202, group 3), or “pathologically- and surgically-identified perforation” (n = 98, group 4). The 4 groups were compared for the frequency of laparoscopic appendectomy and the length of hospital stay using multivariable logistic regression analyses.

Results

The reference standard for appendiceal perforation was frequently missing or inconsistent in the previous studies. Laparoscopic appendectomies were less frequent in groups 3 (52.5%, P = 0.001) and 4 (65%, P = 0.040) than in group 1 (70.7%), while group 2 (73%, P = 0.125) did not significantly differ from group 1. Median hospital stays were 2.9, 3.0, 5.1, and 6.0 days for groups 1–4, respectively. Prolonged hospital stay (≥3.7 days) was more frequent in groups 3 (77.7%, P < 0.001) and 4 (89%, P < 0.001) than in group 1 (23.4%), while group 2 (35%, P = 0.070) did not significantly differ from group 1.

Conclusion

We recommend using surgical rather than pathologic findings as the reference standard for the presence of appendiceal perforation in future investigations.

Appendectomy: Should it Be Performed So Quickly?

Controversy surrounds appendectomy timings and their effects on postoperative outcomes. This study evaluated the influence of hospital delays on perforation rates and complications in patients with acute appendicitis. From January 2008 to December 2013, the cases of 4148 consecutive patients who had undergone appendectomies for suspected appendicitis were reviewed. The patients' demographic data, times from symptom onset to hospital arrival (prehospital delay), times from hospital arrival to surgery (hospital delay), histological findings, and postoperative outcomes were documented. Perforation rates and complications were assessed at each time interval between symptom onset and surgery. Perforation rates and complications increased with longer prehospital delays, but no correlations were evident between hospital delays and perforation rates or between hospital delays and complications. Although delaying appendectomies for >18 hours had no statistically significant impact on perforation rates (25.3 vs 19.4%, P = 0.133), it caused more complications (8.7 vs 3.8%, P = 0.023) compared with cases delayed for 12 to 18 hours. Multivariate analyses determined that hospital delays were not associated with increased risks of perforation, complications, wound infections, or intra-abdominal abscesses. However, a >18-hour hospital delay was associated with a significantly increased risk of postoperative ileus (odds ratio = 2.94, 95% confidence interval = 1.17-7.41, P = 0.022). Hospital delays were not associated with significantly increased risks of perforation and complications. However, patients with perforated appendicitis had higher risks of developing postoperative ileus if hospital delays were >18 hours. Therefore, hospital delays of ≤18 hours are safe, but caution is required if delays are >18 hours.

Less negative appendectomies due to imaging in patients with suspected appendicitis

BACKGROUND

The optimal diagnostics and treatment of acute appendicitis continues to be a challenge. We evaluated the implementation of the guideline "diagnostics and treatment in acute appendicitis" in 2010. This guideline states that, in every patient with clinically suspected acute appendicitis, an ultrasonography or CT scan is advised to confirm the diagnosis before surgery.

PATIENTS AND METHODS

We selected all consecutive patients with acute appendicitis in our hospital in the years 2008 and 2011. We compared the use of imaging and the operation results in both years.

RESULTS

In 2008, 228 patients were treated for acute appendicitis. In 43 %, imaging was performed. In 2011, 238 patients were treated; in 99 % of the cases, imaging was performed. A decrease in patients with negative appendectomy was seen from 19 % in 2008 to 5 % in 2011. Financial analysis showed a reduction in costs favoring 2011.

CONCLUSIONS

The increased use of pre-operative imaging in patients with suspected acute appendicitis resulted in a cost-effective way to decrease the number of patients with negative appendectomies.

Time to appendectomy and risk of perforation in acute appendicitis

IMPORTANCE

In the traditional model of acute appendicitis, time is the major driver of disease progression; luminal obstruction leads inexorably to perforation without timely intervention. This perceived association has long guided clinical behavior related to the timing of appendectomy.

OBJECTIVE

To evaluate whether there is an association between time and perforation after patients present to the hospital.

DESIGN, SETTING, AND PARTICIPANTS

Using data from the Washington State Surgical Care and Outcomes Assessment Program (SCOAP), we evaluated patterns of perforation among patients (≥18 years) who underwent appendectomy from January 1, 2010, to December 31, 2011. Patients were treated at 52 diverse hospitals including urban tertiary centers, a university hospital, small community and rural hospitals, and hospitals within multi-institutional organizations.

MAIN OUTCOMES AND MEASURES

The main outcome of interest was perforation as diagnosed on final pathology reports. The main predictor of interest was elapsed time as measured between presentation to the hospital and operating room (OR) start time. The relationship between in-hospital time and perforation was adjusted for potential confounding using multivariate logistic regression. Additional predictors of interest included sex, age, number of comorbid conditions, race and/or ethnicity, insurance status, and hospital characteristics such as community type and appendectomy volume.

RESULTS

A total of 9048 adults underwent appendectomy (15.8% perforated). Mean time from presentation to OR was the same (8.6 hours) for patients with perforated and nonperforated appendicitis. In multivariate analysis, increasing time to OR was not a predictor of perforation, either as a continuous variable (odds ratio =  1.0 [95% CI, 0.99-1.01]) or when considered as a categorical variable (patients ordered by elapsed time and divided into deciles). Factors associated with perforation were male sex, increasing age, 3 or more comorbid conditions, and lack of insurance.

CONCLUSIONS AND RELEVANCE

There was no association between perforation and in-hospital time prior to surgery among adults treated with appendectomy. These findings may reflect selection of those at higher risk of perforation for earlier intervention or the effect of antibiotics begun at diagnosis but they are also consistent with the hypothesis that perforation is most often a prehospital occurrence and/or not strictly a time-dependent phenomenon. These findings may also guide decisions regarding personnel and resource allocation when considering timing of nonelective appendectomy.

Acute appendicitis: investigating an optimal outer appendiceal diameter cut-point in a pediatric population

BACKGROUND

Acute appendicitis is the most common cause of abdominal pain in children requiring operative intervention. Among a number of sonographic criteria to aid in the diagnosis of appendicitis, an outer diameter >6 mm is the most objective and widely accepted. However, there is a lack of evidence-based standards governing this consensus.

STUDY OBJECTIVES

The aim of this study was to determine the outer appendiceal diameter that maximizes sensitivity and specificity in a pediatric population.

METHODS

A retrospective review of all urgent diagnostic ultrasounds (US) was performed over 2 years in children aged <18 years. The diagnostic accuracy of various cut-points was assessed by calculating the sensitivity and specificity and plotting a receiver operating characteristic (ROC) curve.

RESULTS

The study sample consisted of 398 patients in whom the appendix was visualized on US. The median outer appendiceal diameter was significantly higher in the surgical group compared to the nonsurgical group (9.4 mm; range = 8.1-12.0 vs. 5.5 mm; range = 4.4-6.5, p < 0.01). The optimal cut-point with the greatest area under the ROC curve was determined to be an outer appendiceal diameter of 7.0 mm.

CONCLUSIONS

In our patients, adopting a 7-mm rather than a 6-mm appendiceal diameter threshold would balance a greater number of missed cases of acute appendicitis for a reduction in the number of unnecessary surgeries.

Examining a common disease with unknown etiology: trends in epidemiology and surgical management of appendicitis in California, 1995-2009

BACKGROUND

The study was designed to examine the epidemiology of appendicitis and risk factors of perforation and appendectomy.

METHODS

Retrospective analysis of the California Office of Statewide Health Planning and Development Patient Discharge Data was performed from 1995 to 2009. Patients with appendicitis were identified by ICD-9 diagnosis code. Population statistics from the RAND Corporation were used to calculate incidence rates. Risk factors of perforation and appendectomy were also calculated.

RESULTS

A total of 608,116 patients with appendicitis (70% non-perforated) were included. The incidence increased at an average rate of 0.5 cases/100,000 population/year (p<0.001), with annual incidence peaking during the third quarter. Children age 10-14 had the highest rates of appendicitis (169.6 cases/100,000). The lifetime cumulative incidence rate is 9.0%. Appendicitis is most common in whites and Hispanics and less common in African Americans and Asians. Risks of perforation include Hispanic or Asian race, young or old age, and non-private insurance. The adjusted odds of appendectomy increased since 1995 in patients with non-perforated appendicitis (OR 1.5, 95% CI (1.3-1.7); p<0.001), but it decreased in patients with perforated appendicitis (OR 0.4, 95% CI (0.4-0.5); p<0.001).

CONCLUSIONS

This is the largest epidemiological study of appendicitis to our knowledge in recent years. Incidence has increased over time and is higher in the summer months. Whites and Hispanics have higher rates of appendicitis, but Hispanics and Asians and patients with non-private insurance, have higher odds of perforation. Surgical management of perforated appendicitis has decreased over time. It is unknown why the incidence has increased, displays seasonality, and varies by race.

Risk of perforation increases with delay in recognition and surgery for acute appendicitis

BACKGROUND

Appendicitis remains a common indication for urgent surgical intervention in the United States, and early appendectomy has long been advocated to mitigate the risk of appendiceal perforation. To better quantify the risk of perforation associated with delayed operative timing, this study examines the impact of length of inpatient stay preceding surgery on rates of perforated appendicitis in both adults and children.

METHODS

This study was a cross-sectional analysis using the National Inpatient Sample and Kids' Inpatient Database from 1988-2008. We selected patients with a discharge diagnosis of acute appendicitis (perforated or nonperforated) and receiving appendectomy within 7 d after admission. Patients electively admitted or receiving drainage procedures before appendectomy were excluded. We analyzed perforation rates as a function of both age and length of inpatient hospitalization before appendectomy.

RESULTS

Of 683,590 patients with a discharge diagnosis of appendicitis, 30.3% were recorded as perforated. Over 80% of patients underwent appendectomy on the day of admission, approximately 18% of operations were performed on hospital days 2-4, and later operations accounted for <1% of cases. During appendectomy on the day of admission, the perforation rate was 28.8%; this increased to 33.3% for surgeries on hospital day 2 and 78.8% by hospital day 8 (P<0.001). Adjusted for patient, procedure, and hospital characteristics, odds of perforation increased from 1.20 for adults and 1.08 for children on hospital day 2 to 4.76 for adults and 15.42 for children by hospital day 8 (P<0.001).

CONCLUSIONS

Greater inpatient delay before appendectomy is associated with increased perforation rates for children and adults within this population-based study. These findings align with previous studies and with the conventional progressive pathophysiologic appendicitis model. Randomized prospective studies are needed to determine which patients benefit from nonoperative versus surgically aggressive management strategies for acute appendicitis.

Risk of perforation increases with delay in recognition and surgery for acute appendicitis

BACKGROUND

Appendicitis remains a common indication for urgent surgical intervention in the United States, and early appendectomy has long been advocated to mitigate the risk of appendiceal perforation. To better quantify the risk of perforation associated with delayed operative timing, this study examines the impact of length of inpatient stay preceding surgery on rates of perforated appendicitis in both adults and children.

METHODS

This study was a cross-sectional analysis using the National Inpatient Sample and Kids' Inpatient Database from 1988-2008. We selected patients with a discharge diagnosis of acute appendicitis (perforated or nonperforated) and receiving appendectomy within 7 d after admission. Patients electively admitted or receiving drainage procedures before appendectomy were excluded. We analyzed perforation rates as a function of both age and length of inpatient hospitalization before appendectomy.

RESULTS

Of 683,590 patients with a discharge diagnosis of appendicitis, 30.3% were recorded as perforated. Over 80% of patients underwent appendectomy on the day of admission, approximately 18% of operations were performed on hospital days 2-4, and later operations accounted for <1% of cases. During appendectomy on the day of admission, the perforation rate was 28.8%; this increased to 33.3% for surgeries on hospital day 2 and 78.8% by hospital day 8 (P<0.001). Adjusted for patient, procedure, and hospital characteristics, odds of perforation increased from 1.20 for adults and 1.08 for children on hospital day 2 to 4.76 for adults and 15.42 for children by hospital day 8 (P<0.001).

CONCLUSIONS

Greater inpatient delay before appendectomy is associated with increased perforation rates for children and adults within this population-based study. These findings align with previous studies and with the conventional progressive pathophysiologic appendicitis model. Randomized prospective studies are needed to determine which patients benefit from nonoperative versus surgically aggressive management strategies for acute appendicitis.

Interval routine appendectomy following conservative treatment of acute appendicitis: Is it really needed

Conservative management of acute appendicitis (AA) is gradually being adopted as a valuable therapeutic choice in the treatment of selected patients with AA. This approach is based on the results of many recent studies indicating that it is a valuable and effective alternative to routine emergency appendectomy. Existing data do not support routine interval appendectomy following successful conservative management of AA; indeed, the risk of recurrence is low. Moreover, recurrences usually exhibit a milder clinical course compared to the first episode of AA. The role of routine interval appendectomy is also questioned recently, even in patients with AA complicated by plastron or localized abscess formation. Surgical judgment is required to avoid misdiagnosis when selecting a conservative approach in patients with a presumed “appendiceal” mass.

Safety and efficacy of antibiotics compared with appendicectomy for treatment of uncomplicated acute appendicitis: meta-analysis of randomised controlled trials

OBJECTIVE

To compare the safety and efficacy of antibiotic treatment versus appendicectomy for the primary treatment of uncomplicated acute appendicitis.

DESIGN

Meta-analysis of randomised controlled trials.

POPULATION

Randomised controlled trials of adult patients presenting with uncomplicated acute appendicitis, diagnosed by haematological and radiological investigations.

INTERVENTIONS

Antibiotic treatment versus appendicectomy.

OUTCOME MEASURES

The primary outcome measure was complications. The secondary outcome measures were efficacy of treatment, length of stay, and incidence of complicated appendicitis and readmissions.

RESULTS

Four randomised controlled trials with a total of 900 patients (470 antibiotic treatment, 430 appendicectomy) met the inclusion criteria. Antibiotic treatment was associated with a 63% (277/438) success rate at one year. Meta-analysis of complications showed a relative risk reduction of 31% for antibiotic treatment compared with appendicectomy (risk ratio (Mantel-Haenszel, fixed) 0.69 (95% confidence interval 0.54 to 0.89); I(2)=0%; P=0.004). A secondary analysis, excluding the study with crossover of patients between the two interventions after randomisation, showed a significant relative risk reduction of 39% for antibiotic therapy (risk ratio 0.61 (0.40 to 0.92); I(2)=0%; P=0.02). Of the 65 (20%) patients who had appendicectomy after readmission, nine had perforated appendicitis and four had gangrenous appendicitis. No significant differences were seen for treatment efficacy, length of stay, or risk of developing complicated appendicitis.

CONCLUSION

Antibiotics are both effective and safe as primary treatment for patients with uncomplicated acute appendicitis. Initial antibiotic treatment merits consideration as a primary treatment option for early uncomplicated appendicitis.

Risk factors for gastric distension in patients with acute appendicitis: a retrospective cohort study

PURPOSE

There has been no report on risk factors for gastric distension (GD) when inducing general anesthesia in an emergency situation. The aim of this study was to clarify the risk factors for GD in patients with acute appendicitis at their hospital visit.

METHODS

We reviewed medical records of patients from April 2007 to March 2010 who underwent open appendectomy for acute appendicitis and were diagnosed pathologically. GD was defined as a larger anteroposterior diameter and larger lateral diameter of the stomach than those of the left kidney in computed tomography (CT) imaging. The primary outcome was the presence of GD. Candidate variables such as patient characteristics, physical findings, and CT imaging findings associated with GD were assessed. Time after beginning of abdominal pain was categorized and compared. Determinants with significant univariate association (P < 0.20) with the primary outcome were used to construct multivariable logistic regression models.

RESULTS

We enrolled 121 patients and divided this cohort into a GD group (44 cases, 36%) and a non-GD group (77 cases, 64%). Results of univariate analysis showed longer duration of time after beginning of abdominal pain (P = 0.016), younger age (P < 0.001), and more frequent distended small bowel (P < 0.001) in the GD group than in the non-GD group. In multivariate analysis, age [odds ratio (OR) = 0.939, P = 0.002] and time after beginning of abdominal pain (OR = 1.807, P = 0.031) were shown to be independent risk factors.

CONCLUSION

Younger appendicitis patients with acute abdominal pain for 1 or more days should be treated as patients with high risk for GD.

Use of antibiotics alone for treatment of uncomplicated acute appendicitis: a systematic review and meta-analysis

BACKGROUND

The use of antibiotics alone in the treatment of uncomplicated acute appendicitis has been controversial. The present report is based on a systematic review and meta-analysis of existing studies that compared antibiotics treatment to appendectomy in patients with uncomplicated acute appendicitis.

METHODS

A Medline search was performed for studies published between 1970 and 2009. Studies were selected based on specific inclusion and exclusion criteria. Six reports comprised of 1,201 patients were analyzed.

RESULTS

In patients treated with antibiotics alone, 6.9 ± 4.4% failed to respond and required appendectomy, and acute appendicitis recurred in 14.2 ± 10.6%. One appendectomy patient had a recurrence. A normal appendix was found in 7.3 ± 5.1% of patients at appendectomy. Complications were considerably less likely to occur with antibiotic treatment than with appendectomy. Major surgical complications included enterocutaneous fistula and reoperation.

CONCLUSION

In some cases, antibiotic treatment may fail, and there is a risk of recurrence. However, surgically treated patients, including those with the potential for spontaneous resolution and those with a normal appendix, are subjected to the risks of operative morbidity and mortality. Antibiotic therapy incurs significantly fewer complications. Prospective randomized studies are urgently needed to conclusively define the roles of appendectomy and antibiotic treatment in the management of uncomplicated acute appendicitis.

Causes of short-term mortality after appendectomy: a population-based case-controlled study

OBJECTIVE

This case control study is a detailed analysis of the causes of death and the risk factors of short-term mortality after appendectomy.

SUMMARY BACKGROUND DATA

Although death is a rare event after appendectomy, we found a 7-fold excess mortality after appendectomy overall and a 9-fold excess mortality after negative appendectomy, compared to the background population in a previous study from Sweden, in accordance with others.

MATERIALS AND METHODS

All patients who died within 30 days after appendectomy, and controls matched to age, sex and period, were identified of 119,060 patients who were operated with appendectomy in 1987 to 1996 from the Swedish National Inpatient Registry. Causes of death and differences between the cases and controls in comorbidity and appendectomy diagnoses were analyzed on the basis of a review of hospital records. Only patients and controls with appendectomy as the only surgical intervention and without prevalent malignant diagnosis were included in the analysis to avoid bias.

RESULTS

A total of 179 patients who died within 30 days and 400 matched controls remained for the analyses. Nonproductive and negative exploration was strongly associated with mortality [odds ratio (OR), 5.11; confidence interval (CI), 2.09-12.48; P < 0.001 and OR, 2.38; CI, 1.24-4.57; P = 0.009, respectively] in contrast to perforated appendicitis (OR, 1.60; CI, 0.95-2.70; P = 0.078) after adjustment for age, sex, and comorbidity. Chronic obstructive pulmonary disease (OR, 3.31; CI, 1.05-10.45, P = 0.041), renal insufficiency (OR, 2.32; CI, 1.26-4.27; P = 0.007), and diabetes mellitus were also independent risk factors (OR, 2.39; CI, 1.12-5.12; P = 0.025). Cardiovascular or thromboembolic disease was responsible for the death in more than 50% of the cases, whereas appendicitis was responsible in only 17.9%.

CONCLUSIONS

Appendicitis is only responsible for a small portion of the deaths after appendectomy. Comorbidity and negative appendectomy are strongly associated with mortality, suggesting that comorbidity, diagnostic failure, and the anesthesiosurgical trauma may play an important role.

Pediatric appendicitis in New England: epidemiology and outcomes

BACKGROUND

Acute appendicitis is among the most common indications for surgery in children in the Western world. The epidemiology of acute appendicitis in the United States has not been recently analyzed in a population-based cohort study.

METHODS

Here, we describe the epidemiology of acute appendicitis in the pediatric population in New England from 2000 to 2006.

RESULTS

Our results show that there is clustering of perforated and nonperforated appendicitis by hospital catchment area (Moran I index 0.01 and 0.03, respectively). The overall incidence of nonperforated appendicitis decreased over our study period by 9.7% (P < .05), the proportion of perforated appendicitis did not change significantly over our study period, and there was a 38% decrease in the proportion of negative appendectomies (P < .05).

CONCLUSIONS

There were trends toward increased operative volume for pediatric surgeons as well as sharp increases in the use of laparoscopy and early discharge with home health services. Our results demonstrate that the epidemiology, outcomes, and trends in treatment of acute appendicitis continue to change.

Negative appendicectomy and perforation rates in patients undergoing laparoscopic surgery for suspected appendicitis

BACKGROUND

Despite widespread use of imaging technologies including ultrasonography and computed tomography, rates of negative appendicectomy and perforated appendicitis remain high. This trend analysis examined whether rates of negative appendicectomy and perforated appendicitis have decreased over time, and sought to evaluate clinical predictors associated with negative appendicectomy and perforated appendicitis.

METHODS

This analysis was based on the prospective database of the Swiss Association of Laparoscopic and Thoracoscopic Surgery (SALTS). All patients aged 12 years and over undergoing emergency laparoscopic appendicectomy between 1995 and 2006 were included. Unadjusted and risk-adjusted logistic regression analyses were performed.

RESULTS

A total of 7964 patients underwent laparoscopic appendicectomy, of whom 7452 (93.6 per cent) had acute appendicitis and 512 (6.4 per cent) had a macroscopically normal appendix. Perforation occurred in 1230 (16.5 per cent) of those with appendicitis. In multivariable analysis, younger age (12-18 years), female sex, absence of local or generalized peritonitis and an early point during the study period were significant predictors of negative appendicectomy. For perforated appendicitis, significant predictors included age over 36 years, presence of localized or generalized peritonitis, and high American Society of Anesthesiologists grade. The rate of negative appendicectomy decreased from 12.7 per cent in 1995 to 2.8 per cent in 2006, there being a significant reduction in both unadjusted and risk-adjusted analyses (P < 0.001 for trend). In adjusted analyses, the rate of perforated appendicitis did not increase significantly over time.

CONCLUSION

The rate of negative appendicectomy decreased over time, without an accompanying increase in perforated appendicitis. The risk of having a negative appendicectomy was highest in girls aged 12-18 years without local or generalized peritonitis during the early study period, whereas perforation was associated with age over 36 years, presence of localized or generalized peritonitis, and greater co-morbidity. Copyright © 2011 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.

Decision model for acute appendicitis treatment with decision tree technology--a modification of the Alvarado scoring system

BACKGROUND

How to decide the proper time to do laparotomies for acute appendicitis patients is sometimes very difficult, especially in areas with no imaging diagnostic tools. The Alvarado scoring system (ASS) is a convenient and inexpensive decision making tool; however, its accuracy needs to be improved. The decision tree is the most frequently used data mining technology for diagnostic model building. This study used a decision tree to modify the ASS and to prioritize the variables.

METHODS

We collected 532 patients who underwent appendectomy. Patients who had undergone incidental appendectomy were excluded from the study. The decision tree algorithm was constructed with the data mining workbench Clementine version 8.1. It is a top-down algorithm designed to generate a decision tree model with entropy. The algorithm chooses the best decision node with which to separate different classes from empirical data. The Wilcoxon signed rank test, Student t test and chi(2) test were used for statistical analysis.

RESULTS

Among the 532 patients recruited into the study, 420 had acute appendicitis and 112 had normal appendix. Women with acute appendicitis were older than their male counterparts (p < 0.001). All patients had right lower quadrant tenderness. The new model was constructed with decision tree technology, and the accuracy of the diagnostic rate was better than that of ASS (p < 0.001). The sensitivity and specificity of the new model were 0.945 and 0.805, respectively.

CONCLUSION

The new model is more convenient and accurate than ASS. Right lower quadrant tenderness is an inclusion criterion for acute appendicitis diagnosis. Migrating pain and neutrophil count > 75% were significant factors for acute appendicitis diagnosis if ASS score < 6. Although the criteria of nausea/vomiting and white blood cell count > 10,000/dL were significantly different between acute appendicitis and normal appendix, there was no significant contribution of entropy change below the "neutrophil count > 75%" nodes in the model. So they were erased from the decision tree model. Further studies need to be conducted to investigate why older women are at higher risk for acute appendicitis.

The management of right iliac fossa pain - is timing everything?

BACKGROUND

Right iliac fossa (RIF) pain remains the commonest clinical dilemma encountered by general surgeons. We prospectively audited the management of acute RIF pain, examining the relationship between symptom duration, use of pre-operative radiological imaging and patient outcome.

METHODS

Over a six-month period, 302 patients, median age 18 years, 59% female, were admitted with RIF pain. Symptoms, clinical findings and laboratory results were documented. Patient management, timing of radiological investigations and operations, and outcome were recorded prospectively.

RESULTS

Non-specific abdominal pain (26%), gynaecological (22%) and miscellaneous causes (14%) accounted for most admissions. Ultimately, 119 patients (39%) had appendicitis. Anorexia, tachycardia or rebound tenderness in the RIF significantly predicted a final diagnosis of appendicitis. Patients with perforated appendicitis (n = 29) had a longer duration of pre-hospital symptoms (median 50h) compared to those with simple appendicitis (median 17 h) (p<0.001). The use of pre-operative imaging resulted in an increased time to surgery but was not associated with increased post-operative morbidity or perforated appendicitis.

CONCLUSION

The majority of patients presenting to hospital with RIF pain did not have appendicitis. Increased duration of pre-hospital symptoms was the main factor associated with perforated appendicitis. However, increased in-hospital time to theatre was not associated with perforated appendicitis or post-operative morbidity.

Progress of tissue injury in appendicitis involves the serine proteases uPA and PAI-1

OBJECTIVE

Serine proteases and the matrix metalloproteinases (MMPs) are key factors in the proteolytic cascade and participate in extracellular matrix (ECM) degradation. Fibrinolytic activators and inhibitors may have an effect on inflammatory cells, thereby modulating the inflammatory response. It is reasonable to assume that they may be implicated in the tissue injury in acute appendicitis that subsequently leads to appendix perforation. The purpose of this study was to investigate the expression and distribution of urokinase-type plasminogen activator (uPA) and plasminogen-activator inhibitor type 1 (PAI-1) in appendicitis.

MATERIAL AND METHODS

Expression of uPA and expression of PAI-1 were measured in tissue specimens from patients with appendicitis (n=30) and in control specimens (n=9), using the quantitative ELISA technique. Distribution of enzymes was studied with immunohistochemistry. The uPA and PAI-1 levels in the subgroups of appendicitis and controls were compared.

RESULTS

The overall expressions of uPA and PAI-1 were greater in appendicitis than in control specimens (p <0.001 and p<0.0001, respectively). Expressions of uPA and PAI-1 in phlegmonous (n=15), gangrenous (n=6) and perforated appendicitis (n=9) were all higher than those in controls (n=9), (p<0.01). Moreover, the PAI-1 level was elevated in perforated appendicitis compared with phlegmonous appendicitis (p<0.01). uPA staining was observed in connection with vascular endothelial cells and the serosa stained intensely in specimens from perforated appendicitis.

CONCLUSIONS

The expression of uPA and especially the over-expression of PAI-1 seem to correlate to the progression of local inflammatory response in acute appendicitis.

Elective appendectomy at the time of cesarean delivery: a randomized controlled trial

OBJECTIVE

The purpose of this study was to compare postoperative morbidity in patients who underwent cesarean delivery with and without elective appendectomy.

STUDY DESIGN

Subjects who underwent cesarean delivery were assigned randomly by computer-generated randomization to either standard cesarean delivery or cesarean delivery with appendectomy. Primary variables that were measured were operative times and markers of morbidity. Secondary outcome was appendiceal pathologic condition.

RESULTS

Ninety-three subjects whose condition required cesarean delivery from July 2002 to May 2006 were enrolled (control subjects, 48; active subjects, 45). Operative time in the study group was increased by 8.8 minutes (P < or = .028). Postoperative morbidity findings were similar. Pathologic evaluation revealed 9 abnormalities that included acute appendicitis in 2 patients.

CONCLUSION

Elective appendectomy at the time of cesarean delivery does not increase inpatient morbidity. Consideration can be given safely to elective appendectomy at the time of cesarean delivery in selected cases, such as women with palpable fecaliths and/or an abnormal appearing appendix, a history of pelvic pain, endometriosis, or anticipated intraabdominal adhesions.

Surgery for appendicitis: is it necessary?

BACKGROUND

Appendectomy for acute appendicitis is an effective, universally accepted procedure performed more than 300,000 times annually in the United States. It is generally believed that appendicitis progresses invariably from early inflammation to later gangrene and perforation, and that appendectomy is required for surgical source control. Although non-operative management with antibiotics of uncomplicated diverticulitis, salpingitis, and neonatal enterocolitis is now established, the non-operative management of appendicitis remains largely unexplored.

METHODS

Systematic review of published literature and derived expert opinion.

RESULTS

Clinical, epidemiologic, radiologic, and pathologic evidence is presented for spontaneous resolution of uncomplicated acute appendicitis. The pathogenesis of appendicitis is reviewed with specific consideration of the role of bacterial infection in the pathogenesis. Evidence is also provided documenting the clinical success of non-operative management.

CONCLUSIONS

Appendectomy may not be necessary for the majority of patients with acute uncomplicated appendicitis, as many patients resolve spontaneously and others may be treatable with antibiotics alone. However, the supporting documentation is scant and of poor quality. A randomized, prospective trial of non-operative management versus early appendectomy of acute uncomplicated appendicitis corroborated by radiologic imaging is called for.

Appendicitis in HIV-infected patients during the era of highly active antiretroviral therapy

BACKGROUND

Limited studies have suggested increased incidence rates and unusual clinical presentations of appendicitis among HIV-infected patients during the pre-highly active antiretroviral therapy (HAART) era. Data in the HAART era are sparse, and no study has evaluated potential HIV-related risk factors for the development of appendicitis.

METHODS

We retrospectively studied 449 HIV-infected patients receiving care at a US Naval hospital involving 4750 person-years (PY) of follow-up. We also evaluated the rates of appendicitis among HIV-negative persons at our medical facility. We compared demographics, HIV-specific data, and HAART use in HIV-infected patients with and without appendicitis.

RESULTS

Sixteen (3.6%) of 449 patients developed appendicitis after HIV seroconversion. The incidence rate was 337 cases/100 000 PY, more than fourfold higher than among HIV-negative persons. Eighty-eight per cent of cases among HIV-infected patients had an elevated white blood count at presentation, 39% were complicated, and 64% required hospitalization. HIV-infected patients with appendicitis compared with those who did not develop appendicitis were less likely to be receiving HAART (25 vs. 71%, P<0.001), had higher viral loads (3.5 vs. 1.7 log(10) HIV-1 RNA copies/mL, P=0.005), and were younger (median age of 30 vs. 41 years, P<0.002). In the multivariate model, receipt of HAART remained protective [odds ratio (OR) 0.21, P=0.012] for appendicitis, while younger age was positively associated (OR 1.08, P=0.048) with appendicitis.

CONCLUSION

Acute appendicitis occurs at higher incidence rates among HIV-infected patients compared with the general population. Our study demonstrates that the lack of HAART may be a risk factor for appendicitis among HIV-infected patients; further studies are needed.

Impact of body mass index and tobacco smoking on outcome after open appendicectomy

Background

The effect of body mass index (BMI) and smoking on the risk of perforated appendix and postoperative complications in patients undergoing open appendicectomy for acute appendicitis was studied.

Methods

Record linkage was used to identify 6676 male construction workers who underwent open appendicectomy for acute appendicitis between 1971 and 2004. Multivariable binomial logistic regression analyses were performed.

Results

After adjustment for age, calendar period and BMI, smoking was significantly associated with an increased risk of perforated appendicitis (PA) (P = 0·004). The relative risk was 1·29 (95 per cent confidence interval 1·11 to 1·50) among current smokers with more than 10 pack-years of tobacco use. In patients with non-perforated appendicitis (NPA), the relative risk of overall postoperative complications was significantly associated with BMI (P &lt; 0·001), and was 2·60 (1·71 to 3·95) in obese patients and 1·51 (1·03 to 2·22) in current smokers with more than 10 pack-years of tobacco use. In patients with PA, overweight, obesity and smoking status were not associated with an increased risk of overall postoperative complications.

Conclusion

Perforation due to acute appendicitis was associated with current tobacco smoking. A BMI of 27·5 kg/m2 or more and current smoking were associated with overall postoperative complications in patients with NPA.

Small bowel obstruction secondary to an appendiceal tourniquet

BACKGROUND

An 83-year-old lady was admitted with a 3-day history of non-specific abdominal pain that had rapidly increased in severity on the day of admission necessitating an emergency laparotomy. Intra-operative findings demonstrated a mechanical small bowel obstruction secondary to a chronically inflamed appendix acting as a tourniquet around a loop of terminal ileum.

LEARNING POINT

This case highlights an extremely rare and life-threatening complication of appendicitis.

LITERATURE REVIEW

True mechanical small bowel obstruction secondary to an acutely or chronically inflamed appendix encircling the distal small bowel remains extremely rare with only ten cases reported in the literature.

CONCLUSION

Clinical assessment remains paramount in the treatment of these patients to facilitate prompt diagnosis and treatment which is vital to provide an optimal platform for post-operative recovery and survival. Although CT imaging is a highly effective investigative modality in these cases, operative treatment should not be delayed for a radiological investigation in the presence of abdominal peritonism.

Disparities in appendicitis rupture rate among mentally ill patients

BACKGROUND

Many studies have been carried out that focus on mental patients' access to care for their mental illness, but very few pay attention on these same patients' access to care for their physical diseases. Acute appendicitis is a common surgical emergency. Our population-based study was to test for any possible association between mental illness and perforated appendicitis. We hypothesized that there are significant disparities in access to timely surgical care between appendicitis patients with and without mental illness, and more specifically, between patients with schizophrenia and those with another major mental illness.

METHODS

Using the National Health Insurance (NHI) hospital-discharge data, we compared the likelihood of perforated appendix among 97,589 adults aged 15 and over who were hospitalized for acute appendicitis in Taiwan between the years 1997 to 2001. Among all the patients admitted for appendicitis, the outcome measure was the odds of appendiceal rupture vs. appendicitis that did not result in a ruptured appendix.

RESULTS

After adjusting for age, gender, ethnicity, socioeconomic status (SES) and hospital characteristics, the presence of schizophrenia was associated with a 2.83 times higher risk of having a ruptured appendix (odds ratio [OR], 2.83; 95% confidence interval [CI], 2.20-3.64). However, the presence of affective psychoses (OR, 1.15; 95% CI: 0.77-1.73) or other mental disorders (OR, 1.58; 95% CI: 0.89-2.81) was not a significant predictor for a ruptured appendix.

CONCLUSION

These findings suggest that given the fact that the NHI program reduces financial barriers to care for mentally ill patients, they are still at a disadvantage for obtaining timely treatment for their physical diseases. Of patients with a major mental illness, schizophrenic patients may be the most vulnerable ones for obtaining timely surgical care.

Can Acute Appendicitis be Treated by Antibiotics Alone?

Emergency appendectomy at presentation has been the standard of care for acute appendicitis. We examined the use of antibiotics as an alternative treatment. From September 2002 to August 2003, 170 consecutive patients diagnosed with acute appendicitis without abscess were reviewed retrospectively. Patients were divided into two groups: Group I (n = 151) underwent emergency appendectomy and Group II (n = 19) received antibiotics alone. The mode of treatment was at the attending surgeon's discretion. The overall complication rate was eight per cent for Group I and 10 per cent for Group II patients ( P = 0.22). Group II patients suffered no complications during antibiotic treatment, and any complications that did occur developed after subsequent appendectomy. One Group II patient had recurrent appendicitis (5%). The length of stay was 2.61 ± 0.21 days for Group I and 2.95 ± 0.38 days for Group II patients ( P = 0.57). Patients with acute appendicitis may be treated safely with antibiotics alone without emergency appendectomy.

Search for evidence of recurring or persistent viruses in Crohn's disease

New-onset Crohn's disease and acute flares are often associated with viral infections. The aim of this study was to search for evidence of persistent or recurrent viruses in patients. Tissue blocks were obtained from surgical specimens from patients and a control population. 111 samples were tested by PCR or RT-PCR, for EBV, CMV, HSV 1, HSV 2, HHV 8, pestiviruses, and enteroviruses. Additionally, seven sets of serum samples, including pre-operative and post-operative samples, from CD patients were analyzed serologically for antibodies to EBV. The tests revealed evidence of EBV nucleic acid in tissues of 11 patients from a total of 70 tested (15.7%) and in tissues of 3 of 41 control subjects (7.3%). Evidence of pestivirus was found in one CD patient, while one patient and one control were positive for CMV. No HSV 1 or 2, HHV 8 or enteroviruses were found. The serologic tests revealed that five of seven CD patients had antibodies against the early protein, the capsid protein and the EBV nuclear antigen (EBNA). The titers were not significantly altered post-surgically. None of the patients had antibodies of the IgM isotype. Our findings vary from those of Ruther et al. who demonstrated evidence of EBV in tissues from 7 of 11 (64%) German CD patients. Antibodies to early EBV viral antigen and to nuclear antigen in five of seven Belgian patients suggest persistent active viral infection.