Genetic and environmental influences on the risk of acute appendicitis in twins

Trends and levels of the global, regional, and national burden of appendicitis between 1990 and 2021: findings from the Global Burden of Disease Study 2021

BACKGROUND

Appendicitis is a common surgical emergency that poses a large clinical and economic burden. Understanding the global burden of appendicitis is crucial for evaluating unmet needs and implementing and scaling up intervention services to reduce adverse health outcomes. This study aims to provide a comprehensive assessment of the global, regional, and national burden of appendicitis, by age and sex, from 1990 to 2021.

METHODS

Vital registration and verbal autopsy data, the Cause of Death Ensemble model (CODEm), and demographic estimates from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) were used to estimate cause-specific mortality rates (CSMRs) for appendicitis. Incidence data were extracted from insurance claims and inpatient discharge sources and analysed with disease modelling meta-regression, version 2.1 (DisMod-MR 2.1). Years of life lost (YLLs) were estimated by combining death counts with standard life expectancy at the age of death. Years lived with disability (YLDs) were estimated by multiplying incidence estimates by an average disease duration of 2 weeks and a disability weight for abdominal pain. YLLs and YLDs were summed to estimate disability-adjusted life-years (DALYs).

FINDINGS

In 2021, the global age-standardised mortality rate of appendicitis was 0·358 (95% uncertainty interval [UI] 0·311-0·414) per 100 000. Mortality rates ranged from 1·01 (0·895-1·13) per 100 000 in central Latin America to 0·054 (0·0464-0·0617) per 100 000 in high-income Asia Pacific. The global age-standardised incidence rate of appendicitis in 2021 was 214 (174-274) per 100 000, corresponding to 17 million (13·8-21·6) new cases. The incidence rate was the highest in high-income Asia Pacific, at 364 (286-475) per 100 000 and the lowest in western sub-Saharan Africa, at 81·4 (63·9-109) per 100 000. The global age-standardised rates of mortality, incidence, YLLs, YLDs, and DALYs due to appendicitis decreased steadily between 1990 and 2021, with the largest reduction in mortality and YLL rates. The global annualised rate of decline in the DALY rate was greatest in children younger than the age of 10 years. Although mortality rates due to appendicitis decreased in all regions, there were large regional variations in the temporal trend in incidence. Although the global age-standardised incidence rate of appendicitis has steadily decreased between 1990 and 2021, almost half of GBD regions saw an increase of greater than 10% in their age-standardised incidence rates.

INTERPRETATION

Slow but promising progress has been observed in reducing the overall burden of appendicitis in all regions. However, there are important geographical variations in appendicitis incidence and mortality, and the relationship between these measures suggests that many people still do not have access to quality health care. As the incidence of appendicitis is rising in many parts of the world, countries should prepare their health-care infrastructure for timely, high-quality diagnosis and treatment. Given the risk that improved diagnosis may counterintuitively drive apparent rising trends in incidence, these efforts should be coupled with improved data collection, which will also be crucial for understanding trends and developing targeted interventions.

FUNDING

Bill and Melinda Gates Foundation.

Unusual Acute Appendicitis Complicated by Sepsis, Evisceration, and Ileostomy: A Case Report

Acute appendicitis stands as a prevalent cause necessitating surgical intervention globally, predominantly affecting young adults and children, with notably lower incidence among the elderly. Timely diagnosis facilitates effective management, mitigating the risk of severe complications. In this report, we present the case of a 59-year-old patient whose delayed diagnosis and consequently delayed surgical treatment led to serious complications. After the appendectomy, the patient, due to developing sepsis, was transferred to the intensive care unit. On the seventh postoperative day, complications were found in the form of wound dehiscence along with perforation of the jejunum. The second surgery involved a classic laparotomy, encompassing partial resection of the small intestine, and the creation of a single-barrel ileostomy. Further conservative treatment was implemented, and drainage of the abscess was performed. After treatment in the ICU, the patient was transferred to the surgical ward for further treatment. During the hospital stay, further conservative treatment was implemented, resulting in the improvement of the patient's general condition and resolution of symptoms. The patient was discharged home in optimal general condition with recommendations. After six months, the patient was brought to the surgical ward for reconstructive surgery to reestablish gastrointestinal continuity, which was carried out successfully.

Appendectomy versus antibiotic treatment for acute appendicitis

BACKGROUND

Acute appendicitis is one of the most common emergency general surgical conditions worldwide. Uncomplicated/simple appendicitis can be treated with appendectomy or antibiotics. Some studies have suggested possible benefits with antibiotics with reduced complications, length of hospital stay, and the number of days off work. However, surgery may improve success of treatment as antibiotic treatment is associated with recurrence and future need for surgery.

OBJECTIVES

To assess the effects of antibiotic treatment for uncomplicated/simple acute appendicitis compared with appendectomy for resolution of symptoms and complications.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, and two trial registers (World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov) on 19 July 2022. We also searched for unpublished studies in conference proceedings together with reference checking and citation search. There were no restrictions on date, publication status, or language of publication.

SELECTION CRITERIA

We included parallel-group randomised controlled trials (RCTs) only. We included studies where most participants were adults with uncomplicated/simple appendicitis. Interventions included antibiotics (by any route) compared with appendectomy (open or laparoscopic).

DATA COLLECTION AND ANALYSIS

We used standard methodology expected by Cochrane. We used GRADE to assess the certainty of evidence for each outcome. Primary outcomes included mortality and success of treatment, and secondary outcomes included number of participants requiring appendectomy in the antibiotic group, complications, pain, length of hospital stay, sick leave, malignancy in the antibiotic group, negative appendectomy rate, and quality of life. Success of treatment definitions were heterogeneous although mainly based on resolution of symptoms rather than incorporation of long-term recurrence or need for surgery in the antibiotic group.

MAIN RESULTS

We included 13 studies in the review covering 1675 participants randomised to antibiotics and 1683 participants randomised to appendectomy. One study was unpublished. All were conducted in secondary care and two studies received pharmaceutical funding. All studies used broad-spectrum antibiotic regimens expected to cover gastrointestinal bacteria. Most studies used predominantly laparoscopic surgery, but some included mainly open procedures. Six studies included adults and children. Almost all studies aimed to exclude participants with complicated appendicitis prior to randomisation, although one study included 12% with perforation. The diagnostic technique was clinical assessment and imaging in most studies. Only one study limited inclusion by sex (male only). Follow-up ranged from hospital admission only to seven years. Certainty of evidence was mainly affected by risk of bias (due to lack of blinding and loss to follow-up) and imprecision. Primary outcomes It is uncertain whether there was any difference in mortality due to the very low-certainty evidence (Peto odds ratio (OR) 0.51, 95% confidence interval (CI) 0.05 to 4.95; 1 study, 492 participants). There may be 76 more people per 1000 having unsuccessful treatment in the antibiotic group compared with surgery, which did not reach our predefined level for clinical significance (risk ratio (RR) 0.91, 95% CI 0.87 to 0.96; I2 = 69%; 7 studies, 2471 participants; low-certainty evidence). Secondary outcomes At one year, 30.7% (95% CI 24.0 to 37.8; I2 = 80%; 9 studies, 1396 participants) of participants in the antibiotic group required appendectomy or, alternatively, more than two-thirds of antibiotic-treated participants avoided surgery in the first year, but the evidence is very uncertain. Regarding complications, it is uncertain whether there is any difference in episodes of Clostridium difficile diarrhoea due to very low-certainty evidence (Peto OR 0.97, 95% CI 0.24 to 3.89; 1 study, 1332 participants). There may be a clinically significant reduction in wound infections with antibiotics (RR 0.25, 95% CI 0.09 to 0.68; I2 = 16%; 9 studies, 2606 participants; low-certainty evidence). It is uncertain whether antibiotics affect the incidence of intra-abdominal abscess or collection (RR 1.58, 95% CI 0.61 to 4.07; I2 = 19%; 6 studies, 1831 participants), or reoperation (Peto OR 0.13, 95% CI 0.01 to 2.16; 1 study, 492 participants) due to very low-certainty evidence, mainly due to rare events causing imprecision and risk of bias. It is uncertain if antibiotics prolonged length of hospital stay by half a day due to the very low-certainty evidence (MD 0.54, 95% CI 0.06 to 1.01; I2 = 97%; 11 studies, 3192 participants). The incidence of malignancy was 0.3% (95% CI 0 to 1.5; 5 studies, 403 participants) in the antibiotic group although follow-up was variable. Antibiotics probably increased the number of negative appendectomies at surgery (RR 3.16, 95% CI 1.54 to 6.49; I2 = 17%; 5 studies, 707 participants; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

Antibiotics may be associated with higher rates of unsuccessful treatment for 76 per 1000 people, although differences may not be clinically significant. It is uncertain if antibiotics increase length of hospital stay by half a day. Antibiotics may reduce wound infections. A third of the participants initially treated with antibiotics required subsequent appendectomy or two-thirds avoided surgery within one year, but the evidence is very uncertain. There were too few data from the included studies to comment on major complications.

Misdiagnosis of Acute Appendicitis Cases in the Emergency Room

Acute appendicitis (AA) is one of the most frequent surgical emergencies, especially in pediatric populations, with its misdiagnosis in emergency settings presenting significant health risks. This misdiagnosis leads to various complications, such as delayed treatment or unnecessary surgeries. Factors such as age, gender, and comorbidities contribute to diagnostic errors, leading to complications such as peritonitis and increased negative appendectomy rates. This underscores the importance of accurate clinical assessment and awareness of common pitfalls, such as cognitive biases and over-reliance on laboratory tests. This review delves into the prevalence of AA misdiagnosis, its health burden, and the challenges inherent in the diagnostic process. It scrutinizes the effectiveness of different diagnostic approaches, including clinical assessment and imaging techniques. The treatment paradigms for AA are also explored, focusing on surgical interventions and the potential of conservative treatments using antibiotics. The review underscores the criticality of precise diagnosis in preventing adverse outcomes and ensuring effective treatment.

Investigation of VGLL3 and sub-target genes in the aetiology of paediatric acute appendicitis: a prospective case-control study

PURPOSE

Vestigial like family member 3 (VGLL3) and its sub-target genes show considerable transcriptomic overlap in terms of several autoimmune and inflammatory diseases. Herein, we investigated the role of VGLL3 rs13074432 polymorphism and its sub-target genes in the aetiology of acute appendicitis (AA).

METHODS

In this prospective case-control study, we included 250 patients (age, 0-18 years) who underwent appendectomy with the diagnosis of AA (patient group; blood and appendix tissue samples) and 200 healthy children (control group; only blood samples) without appendectomy. ELISA method was used for protein-level detection of VGLL3 and sub-target genes expression change in obtained tissue samples, and real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used for mRNA level detection. Genotyping analyses were performed on DNA samples isolated from blood using TaqMan SNP genotyping test.

RESULTS

The frequency of TT variant genotype (p < 0.001) and T allele (p = 0.002) showed a significant decrease in the patient group compared with the control group. No significant correlation was observed between the expression of VGLL3 in the appendiceal tissue and patient clinical and demographic data (p > 0.050).

CONCLUSION

This study revealed that the VGLL3 gene and its sub-target genes are associated with AA aetiology.

Typical and Atypical Presentations of Appendicitis and Their Implications for Diagnosis and Treatment: A Literature Review

Appendicitis, an acute inflammation of the appendix, affects all demographic groups and exhibits various incidences and clinical manifestations. While acute appendicitis typically presents with colicky periumbilical abdominal pain that localizes to the right lower quadrant, atypical presentations are more common in children, geriatric, and pregnant patient populations, leading to delays in diagnosis. Clinical evaluation, clinical scoring systems, and inflammatory markers are commonly used, but their limitations have led to the increased use of diagnostic imaging in patients suspected of appendicitis. Acute appendicitis is managed by non-operative and operative management, depending on whether it is uncomplicated or complicated. Developing diagnostic pathways to improve outcomes and reduce complications is crucial. Although medical advancements have been made, diagnosing and managing appendicitis can be challenging, mainly when patients are present atypically. This literature review aims to comprehensively review typical and atypical presentations of appendicitis and their current implications for diagnosis and treatment modalities in pediatric, adult, pregnant, and geriatric patient populations.

The global, regional, and national burden of appendicitis in 204 countries and territories, 1990-2019: a systematic analysis from the Global Burden of Disease Study 2019

BACKGROUND

Appendicitis is the most common abdominal surgical emergency worldwide, and its burden has been changing. We report the level and trends of appendicitis prevalence, and incidence; and years lived with disability (YLD) in 204 countries and territories from 1990 to 2019, based on data from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019.

METHODS

The numbers and age-standardized prevalence, incidence, and YLD rates per 100,000 population of appendicitis were estimated across regions and countries by age, sex, and sociodemographic index (SDI). All the estimates were reported with 95% uncertainty intervals (UIs).

RESULTS

Globally, the age-standardized prevalence and incidence rates of appendicitis in 2019 were 8.7 (95% UI 6.9 to 11.0) and 229.9 (95% UI 180.9 to 291.0) per 100,000 population, with increases of 20.8% (95% UI 18.9 to 23.0%) and 20.5% (95% UI 18.7 to 22.8%) from 1990 to 2019, respectively. Additionally, the age-standardized YLDs rate was 2.7 (95% UI 1.8 to 3.9) in 2019, with an increase of 20.4% (95% UI 16.2 to 25.1%) from 1990 to 2019. In 2019, the age-standardized prevalence, incidence, and YLD rates peaked in the 15-to-19-year age groups in both male and female individuals. However, no statistically significant differences were observed between the male and female individuals in all groups. Ethiopia, India, and Nigeria showed the largest increases in the age-standardized prevalence rate between 1990 and 2019. Generally, positive associations were found between the age-standardized YLD rates and SDI at the regional and national levels.

CONCLUSIONS

Appendicitis remains a major public health challenge globally. Increasing awareness of appendicitis and its risk factors and the importance of early diagnosis and treatment is warranted to reduce its the burden.

A randomized, controlled multicenter feasibility pilot trial on imaging confirmed uncomplicated acute appendicitis: Appendectomy vs. symptomatic treatment in pediatric patients (the APPSYPP) trial study protocol

INTRODUCTION

Imaging-confirmed uncomplicated acute appendicitis can be effectively and safely treated with antibiotics in most adults and children. Symptomatic treatment may have similar efficacy and safety.

METHODS AND ANALYSIS

The APPSYPP trial is a randomized national multicenter feasibility superiority pilot study comparing appendectomy with symptomatic treatment in children with imaging-confirmed uncomplicated acute appendicitis.

INCLUSION CRITERIA

1) age ≥ 7 and < 16 years, 2) imaging-confirmed uncomplicated acute appendicitis and 3) CRP ≤ 65 mg/l. Patients are randomized to receive emergency laparoscopic appendectomy or symptomatic treatment. To ensure patient safety, symptomatically treated patients are hospitalized for at least 24 h receiving standard practice intravenous fluids and analgesics according to standard clinical practice. Primary outcome is 30-day treatment success defined by the absence of any treatment failure criteria. In appendectomy, treatment failure is defined as normal appendiceal histopathology or any postintervention complication requiring general anesthesia. In symptomatic treatment, treatment failure is defined as 1) inability for hospital discharge without appendectomy within 48 h after randomization with a finding of histopathologically inflamed appendix, 2) appendectomy during the initial hospital stay due to clinical progression of appendicitis with complicated acute appendicitis both histopathologically and surgically, 3) appendectomy with a histopathological finding of acute appendicitis after hospital discharge, or 4) any complication of appendicitis requiring general anesthesia. Detailed predefined secondary outcomes will be analyzed.

ETHICS AND DISSEMINATION

Study was approved by Ethics Committee of Helsinki University Hospital (ID:HUS/1993/2021), conducted in compliance with the declaration of Helsinki with results disseminated in peer-reviewed scientific journals.

TRIAL REGISTRATION

ClinicalTrials.gov (NCT05289713).

STRENGTHS AND LIMITATIONS OF THIS STUDY

Association of Appendicitis Incidence With Warmer Weather Independent of Season

IMPORTANCE

Acute appendicitis is a common cause of abdominal pain and the most common reason for emergency surgery in several countries. Increased cases during summer months have been reported.

OBJECTIVE

To investigate the incidence of acute appendicitis by considering local temperature patterns in geographic regions with different climate over several years.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used insurance claims data from the MarketScan Commercial Claims and Encounters Database and the Medicare Supplemental and Coordination of Benefits Database from January 1, 2001, to December 31, 2017. The cohort included individuals at risk for appendicitis who were enrolled in US insurance plans that contribute data to the MarketScan databases. Cases of appendicitis in the inpatient, outpatient, and emergency department settings were identified using International Classification of Diseases, Ninth Revision, Clinical Modification or International Statistical Classification of Diseases, Tenth Revision, Clinical Modification diagnosis codes. Local weather data were obtained for individuals living in a metropolitan statistical area (MSA) from the Integrated Surface Database. Associations were characterized using a fixed-effects generalized linear model based on a negative binomial distribution. The model was adjusted for age, sex, and day of week and included fixed effects for year and MSA. The generalized linear model was fit with a piecewise linear model by searching each 0.56 °C in temperature for change points. To further isolate the role of temperature, observed temperature was replaced with the expected temperature and the deviation of the observed temperature from the expected temperature for a given city on a given day of year. Data were analyzed from October 1, 2021, to July 31, 2022.

MAIN OUTCOMES AND MEASURES

The primary outcome was the daily number of appendicitis cases in a given city stratified by age and sex, with mean temperature in the MSA over the previous 7 days as the independent variable.

RESULTS

A total of 450 723 744 person-years at risk and 689 917 patients with appendicitis (mean [SD] age, 35 [18] years; 347 473 male [50.4%] individuals) were included. Every 5.56 °C increase in temperature was associated with a 1.3% increase in the incidence of appendicitis (incidence rate ratio [IRR], 1.01; 95% CI, 1.01-1.02) when temperatures were 10.56 °C or lower and a 2.9% increase in incidence (IRR, 1.03; 95% CI, 1.03-1.03) for temperatures higher than 10.56 °C. In terms of temperature deviations, a higher-than-expected temperature increase greater than 5.56 °C was associated with a 3.3% (95% CI, 1.0%-5.7%) increase in the incidence of appendicitis compared with days with near-0 deviations.

CONCLUSIONS AND RELEVANCE

Results of this cohort study observed seasonality in the incidence of appendicitis and found an association between increased incidence and warmer weather. These results could help elucidate the mechanism of appendicitis.

The Role of Alvarado Score in Predicting Acute Appendicitis and Its Severity in Correlation to Histopathology: A Retrospective Study in a Qatar Population

Background/objective

Acute appendicitis (AA) is one of the most common surgical emergencies that require a proper diagnosis to avoid a negative outcome in the case of missed or delayed diagnosis. Our study aims to assess the diagnostic power of the Alvarado score and the prediction of the severity of acute appendicitis in correlation to intraoperative findings and the final histopathology (HP) result.

Methods

This retrospective study was applied to 1,303 patients with clinically proven acute appendicitis (AA) and available HP results. We correlated Alvarado score to the gold standard HP and intraoperative findings. We selected the cutoff point of Alvarado at 5 and 7 as they were the most frequent cutoff value mentioned in the literature and based on the ROC curve in this study to assess sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV).

Results

The mean age of the study cohort is 33.3 ± 9.5 years, with a male predominance (75.8%). The negative appendectomy (NA) rate was 4%. The operative complication rate was 1.2%, and we recorded one mortality case (0.1%). The diagnostic evidence of AA was in 95.9% of cases. Alvarado score ≥ 7 presented sensitivity and specificity of 66.4% and 69.8%, respectively, with PPV of 98.1% and NPV of 8.1%, with an accuracy of 66.5%. For Alvarado score ≥ 5, the sensitivity was 91.2%, specificity was 22.6%, PPV was 96.5%, NPV was 9.8%, and accuracy was 88.4%. In addition, we demonstrated statistical significance between Alvarado risk stratification with HP and intraoperative grades (p = 0.001 each).

Conclusion

The Alvarado scoring system alone is not enough to diagnose AA with unsatisfactory sensitivity and specificity. However, it is a good indicator of the severity of AA that we can depend on to prioritize those patients waiting for surgery.

Impact of Human Genetic Variation on C-Reactive Protein Concentrations and Acute Appendicitis

Background

Acute appendicitis is one of the most common abdominal emergencies worldwide. Both environmental and genetic factors contribute to the disease. C-reactive protein (CRP) is an important biomarker in the diagnosis of acute appendicitis. CRP concentrations are significantly affected by genetic variation. However, whether such genetic variation is causally related to appendicitis risk remains unclear. In this study, the causal relationship between single-nucleotide polymorphisms (SNPs) associated with circulating CRP concentrations and the risk and severity of acute appendicitis was investigated.

Methods

CRP concentrations in serum of appendicitis patients (n = 325) were measured. Appendicitis was categorized as complicated/uncomplicated and gangrenous/non-gangrenous. Imputed SNP data (n = 287) were generated. A genome-wide association study (GWAS) on CRP concentrations and appendicitis severity was performed. Intersection and colocalization of the GWAS results were performed with appendicitis and CRP-associated loci from the Pan-UKBB cohort. A functional-genomics approach to prioritize genes was employed.

Results

Thirteen percent of significant CRP quantitative trait loci (QTLs) that were previously identified in a large cohort of healthy individuals were replicated in our small patient cohort. Significant enrichment of CRP-QTLs in association with appendicitis was observed. Among these shared loci, the two top loci at chromosomes 1q41 and 8p23.1 were characterized. The top SNP at chromosome 1q41 is located within the promoter of H2.0 Like Homeobox (HLX) gene, which is involved in blood cell differentiation, and liver and gut organogeneses. The expression of HLX is increased in the appendix of appendicitis patients compared to controls. The locus at 8p23.1 contains multiple genes, including cathepsin B (CTSB), which is overexpressed in appendix tissue from appendicitis patients. The risk allele of the top SNP in this locus also increases CTSB expression in the sigmoid colon of healthy individuals. CTSB is involved in collagen degradation, MHC class II antigen presentation, and neutrophil degranulation.

Conclusions

The results of this study prioritize HLX and CTSB as potential causal genes for appendicitis and suggest a shared genetic mechanism between appendicitis and CRP concentrations.

The treatment of acute appendicitis in two age-based groups during COVID-19 pandemic: a retrospective experience in a COVID-19 referral hospital

PURPOSE

During the past months, the Italian Government has reduced the restrictions and access to hospitals as well as outpatient. Since then, up to 40% of non-traumatic abdominal emergencies have had unusual delayed treatment. Given the rapidly evolving situation and the absence of evidence to support recommendations during the COVID-19 pandemic, it is useful to assess how the current situation is influencing the management of elderly patients with acute appendicitis.

METHODS

Between February 2020 and December 2020, all patients 18 years or older undergone appendectomy were included. Patients were divided in two age-based groups (young groups, YG; elderly group, EG). Surgical approach, hospital stay, post-operative complications, radiology reports, and histologic examination were included in the retrospective analysis.

RESULTS

One hundred eight patients underwent appendectomy, 81 patients into the YG, and 27 in the EG. Laparoscopy was performed in 87.7% of the YG and in 51.8% of the elderly (p < 0.000), while conversion to laparotomy was necessary in 3.7% in the YG vs 22.3% of the other group (p < 0.009). Open procedures were more frequent in the EG, 25.9% vs 8.6% (p value < 0.05). No mortality rate was reported in both groups; moreover, the mean hospital stay was greater in the EG than the YG (p < 0.000).

CONCLUSION

Our data highlighted a partial delay in diagnosis in the elderly group, and an increase in complicated appendicitis also demonstrated by the need for conversion to laparotomy despite no significant relationship between these findings and the histologic examination was reported.

Distribution of RET proto-oncogene variants in children with appendicitis

Background

In addition to patient‐related systemic factors directing the immune response, the pathomechanisms of appendicitis (AP) might also include insufficient drainage leading to inflammation caused by decreased peristalsis. Genetic predisposition accounts for 30%–50% of AP. M. Hirschsprung (HSCR), also characterized by disturbed peristalsis, is associated with variants in the RET proto‐oncogene. We thus hypothesized that RET variants contribute to the etiology of AP.

Methods

DNA from paraffin‐embedded appendices and clinical data of 264 children were analyzed for the RET c.135A>G variant (rs1800858, NC_000010.11:g.43100520A>G). In 46 patients with gangrenous or perforated AP (GAP), peripheral blood DNA was used for RET sequencing.

Results

Germline mutations were found in 13% of GAP, whereas no RET mutations were found in controls besides the benign variant p.Tyr791Phe (NC_000010.11:g.43118460A>T). In GAP, the polymorphic G‐allele in rs2435352 (NC_000010.11:g.43105241A>G) in intron 4 was underrepresented (p = 0.0317).

Conclusion

Our results suggest an impact of the RET proto‐oncogene in the etiology of AP. Mutations were similar to patients with HSCR but no clinical features of HSCR were observed. The pathological phenotypes in both populations might thus represent a multigenic etiology including RET germline mutations with phenotypic heterogeneity and incomplete penetrance.

Current Practice of Acute Appendicitis Diagnosis and Management in China (PANDA-C): A National Cross-Sectional Survey

Background: The aim of this study was to describe and analyze the current status of the diagnosis and management of acute appendicitis in China. Patients and Methods: An online record system was used to collect data retrospectively from 52 medical centers in mainland China. All patients with acute appendicitis who were first treated at the hospital in 2017 were included and followed up for one year. Propensity score matching (PSM) was used to exclude the potential confounders and analyze the difference in outcomes between the non-operative management (NOM) and surgical groups. Results: A total of 10,187 patients were enrolled, of whom 5,517 (54.2%) were males. A total of 2,056 (20.2%) cases received NOM. The one-year recurrence rate of appendicitis in the NOM group was 19.3%. On PSM analysis, we found that the NOM group had a lower complication rate (2% vs. 4.2%; p = 0.001) and an acceptable success rate (96.8% vs. 100%; p < 0.001) compared with the operative group in patients with non-complicated acute appendicitis. However, in the complicated acute appendicitis population, the in-hospital complication rate in the NOM group was higher (10.8% vs. 5.8%; p = 0.048) and the success rate was lower (95.4% vs. 100%; p < 0.001) than the operative group. The recurrence rate was lower in patients with non-complicated acute appendicitis than in those with complicated acute appendicitis (17.3% vs. 30.8%; p = 0.010). In the operative group, pre-operative antimicrobial prophylaxis-covered anaerobes could reduce the surgical site infection (SSI) rate compared with that in the non-covered anaerobes group in non-complicated patients (0.9% vs. 1.9%; p = 0.020). Conclusions: Appendectomy is currently the most effective treatment for acute appendicitis. However, NOM is an alternative treatment for non-complicated acute appendicitis but not for complicated acute appendicitis because of the lower complication rate, considerable success rate, and recurrence rate.

Impact of the COVID-19 pandemic on appendicitis treatment in Germany-a population-based analysis

PURPOSE

Acute appendicitis is one of the most common reasons for emergency medical consultation. While simple appendicitis can be treated with antibiotics or surgery, complex appendicitis including gangrene, abscess, and perforation requires appendectomy. During the COVID-19 pandemic in early 2020, an overall drop in emergency room consultations was observed. We therefore aimed to investigate the incidence and treatment strategies of acute appendicitis during that period.

METHODS

Data of insurance holders with the ICD code for "acute appendicitis" or OPS procedure of appendectomy of a major health insurance company in Germany were analyzed retrospectively. Groups were built, containing of the means of March-June of 2017, 2018, and 2019, defined as "pre-COVID group" with the "COVID group," defined as data from March to June of 2020. Data was analyzed by age, sex, comorbidities, length of hospital stay, diagnoses, and treatment. Data of the COVID group was analyzed for simultaneous COVID-19 infection.

RESULTS

During the COVID-19 pandemic of early 2020, an overall reduction by 12.9% of patients presenting with acute appendicitis was noticeable. These results were mainly due to decreased rates of uncomplicated appendicitis, while complicated appendicitis was scarcely affected. Especially in the group of females < 40 years, a drastic reduction was visible. Rates of extended surgery did not change. Likewise, the complication rate like appendix stump leakage or need for re-operation did not differ. In March 2020, 4.8% of acute appendicitis patients had concomitant COVID-19 infection.

CONCLUSION

In line with the overall drop of emergency room visits during the COVID-19 pandemic of spring 2020 in Germany, a significantly lowered number of patients with uncomplicated appendicitis were noticeable, whereas complicated appendicitis did not differ. Also, treatment and complication rate of acute appendicitis did not change. These findings might be a hint that acute appendicitis is not a progressing disease but caused by different entities for uncomplicated and complicated appendicitis and therefore another clue that uncomplicated appendicitis can be treated with antibiotics or observation. Nevertheless provided data does not cover outpatient treatment; therefore, no statement observation or antibiotics in outpatients can be made.

Increased risk of gallstones after appendectomy: A longitudinal follow-up study using a national sample cohort

To evaluate the association between appendectomy and the occurrence of gallstones using a national sample cohort from Korea.The Korean National Health Insurance Service-National Sample Cohort was collected from 2002 to 2013. We extracted data for patients who had undergone appendectomy (n = 14,955) and a 1:4 matched control group (n = 59,820) and then analyzed the occurrence of gallstones. The patients were matched according to age, sex, income, region of residence, hypertension, diabetes mellitus, and history of dyslipidemia. Appendectomies were identified using operation codes (Q2860-Q2863) for appendicitis alone (International Classification of Disease-10: K35). Gallstones were diagnosed if the corresponding International Classification of Disease-10 code (K80) was reported ≥2 times. Crude (simple) and adjusted hazard ratios (HRs) were analyzed using stratified Cox proportional hazard models, and 95% confidence intervals were calculated. Subgroup analyses were performed based on age, sex, and time period after appendectomy.The adjusted HR for gallstones was 1.78 (95% confidence interval = 1.51-2.09, P < .001) in the appendectomy group. Consistent HRs were found in the analyses of all the subgroups determined using age and sex, with the exception of men ≥60 years of age. The risk of gallstones was increased during the first year after appendectomy.The occurrence of gallstones was increased in the patients who had undergone appendectomy.

Relationship between appendicitis and diameter of ileocecal lipomatosis and also ileocecal angle

PURPOSE

One of the most widespread surgical conditions is acute appendicitis in industrialized countries. Nevertheless, diagnosis of borderline cases is mostly troublesome and needs subsequent researches. For this reason, we aimed to investigate new parameters to improve estimation of acute appendicitis. Lymphoid hyperplasia, impacted stool, faecolith, caecal or appendiceal tumors have been accepted as causes of appendicitis formation, but anatomic variations of diameter of ileocecal lipomatosis and ileocecal angle have been never discussed before. The aim of this study was to assess the relationship between appendicitis and diameter of ileocecal lipomatosis and ileocecal angle.

MATERIALS AND METHODS

96 Patients (51 women, 45 men) who were found to have acute appendicitis during exploration and 67 patients (32 women, 35 men) who were not pre-diagnosed with acute appendicitis were enrolled in the study. The diameter of ileocecal lipomatosis and also ileocecal angle values were obtained via computed tomography (CT) scans.

RESULTS

There were no significant differences between two groups in the mean of ileocecal angle (p > 0.05) but diameter of ileocecal lipomatosis values was significantly higher in the appendicitis-positive group compared with the appendicitis-negative group (p: 0.001).

CONCLUSIONS

There is a relationship between increase in diameter of ileocecal lipomatosis and appendicitis formation.

Computed tomography for diagnosis of acute appendicitis in adults

BACKGROUND

Diagnosing acute appendicitis (appendicitis) based on clinical evaluation, blood testing, and urinalysis can be difficult. Therefore, in persons with suspected appendicitis, abdominopelvic computed tomography (CT) is often used as an add-on test following the initial evaluation to reduce remaining diagnostic uncertainty. The aim of using CT is to assist the clinician in discriminating between persons who need surgery with appendicectomy and persons who do not.

OBJECTIVES

Primary objective Our primary objective was to evaluate the accuracy of CT for diagnosing appendicitis in adults with suspected appendicitis. Secondary objectives Our secondary objectives were to compare the accuracy of contrast-enhanced versus non-contrast-enhanced CT, to compare the accuracy of low-dose versus standard-dose CT, and to explore the influence of CT-scanner generation, radiologist experience, degree of clinical suspicion of appendicitis, and aspects of methodological quality on diagnostic accuracy.

SEARCH METHODS

We searched MEDLINE, Embase, and Science Citation Index until 16 June 2017. We also searched references lists. We did not exclude studies on the basis of language or publication status.

SELECTION CRITERIA

We included prospective studies that compared results of CT versus outcomes of a reference standard in adults (> 14 years of age) with suspected appendicitis. We excluded studies recruiting only pregnant women; studies in persons with abdominal pain at any location and with no particular suspicion of appendicitis; studies in which all participants had undergone ultrasonography (US) before CT and the decision to perform CT depended on the US outcome; studies using a case-control design; studies with fewer than 10 participants; and studies that did not report the numbers of true-positives, false-positives, false-negatives, and true-negatives. Two review authors independently screened and selected studies for inclusion.

DATA COLLECTION AND ANALYSIS

Two review authors independently collected the data from each study and evaluated methodological quality according to the Quality Assessment of Studies of Diagnostic Accuracy - Revised (QUADAS-2) tool. We used the bivariate random-effects model to obtain summary estimates of sensitivity and specificity.

MAIN RESULTS

We identified 64 studies including 71 separate study populations with a total of 10,280 participants (4583 with and 5697 without acute appendicitis). Estimates of sensitivity ranged from 0.72 to 1.0 and estimates of specificity ranged from 0.5 to 1.0 across the 71 study populations. Summary sensitivity was 0.95 (95% confidence interval (CI) 0.93 to 0.96), and summary specificity was 0.94 (95% CI 0.92 to 0.95). At the median prevalence of appendicitis (0.43), the probability of having appendicitis following a positive CT result was 0.92 (95% CI 0.90 to 0.94), and the probability of having appendicitis following a negative CT result was 0.04 (95% CI 0.03 to 0.05). In subgroup analyses according to contrast enhancement, summary sensitivity was higher for CT with intravenous contrast (0.96, 95% CI 0.92 to 0.98), CT with rectal contrast (0.97, 95% CI 0.93 to 0.99), and CT with intravenous and oral contrast enhancement (0.96, 95% CI 0.93 to 0.98) than for unenhanced CT (0.91, 95% CI 0.87 to 0.93). Summary sensitivity of CT with oral contrast enhancement (0.89, 95% CI 0.81 to 0.94) and unenhanced CT was similar. Results show practically no differences in summary specificity, which varied from 0.93 (95% CI 0.90 to 0.95) to 0.95 (95% CI 0.90 to 0.98) between subgroups. Summary sensitivity for low-dose CT (0.94, 95% 0.90 to 0.97) was similar to summary sensitivity for standard-dose or unspecified-dose CT (0.95, 95% 0.93 to 0.96); summary specificity did not differ between low-dose and standard-dose or unspecified-dose CT. No studies had high methodological quality as evaluated by the QUADAS-2 tool. Major methodological problems were poor reference standards and partial verification primarily due to inadequate and incomplete follow-up in persons who did not have surgery.

AUTHORS' CONCLUSIONS

The sensitivity and specificity of CT for diagnosing appendicitis in adults are high. Unenhanced standard-dose CT appears to have lower sensitivity than standard-dose CT with intravenous, rectal, or oral and intravenous contrast enhancement. Use of different types of contrast enhancement or no enhancement does not appear to affect specificity. Differences in sensitivity and specificity between low-dose and standard-dose CT appear to be negligible. The results of this review should be interpreted with caution for two reasons. First, these results are based on studies of low methodological quality. Second, the comparisons between types of contrast enhancement and radiation dose may be unreliable because they are based on indirect comparisons that may be confounded by other factors.

Acute perforated appendicitis after blunt abdominal trauma: A report from a 7-year-old

Individually, trauma and appendicitis are some of the most common conditions in clinical practice, particularly in emergency medicine. In rare cases, trauma and appendicitis may co-exist, imposing a dilemma of whether these are only coincidence or appendicitis develops because of trauma. We report here a case of acute perforated appendicitis after a blunt abdominal trauma caused by a horse hoof kick to the abdomen in a 7-year-old boy. We also discussed the potential pathophysiologic mechanisms behind and reviewed the literature on this rare condition.

Simultaneous acute appendicitis in identical twin boys

Acute appendicitis is one of the most common causes of abdominal pain in children but remains a diagnostic challenge, and insight into the aetiology of the condition is lacking. A case of simultaneous acute appendicitis in monozygotic twin boys is reported here. Familial aggregation in acute appendicitis has been described, but the underlying causes for this are not well understood. The patients reported here were both genetically identical and lived a mostly identical lifestyle. Their simultaneous presentation would be exceedingly rare if explained entirely by chance, suggesting a role for both genetic and environmental influences. Increased knowledge of this occurrence may assist in prompt diagnosis and reporting on the incidence and timing of appendicitis in monozygotic twins could better elucidate the genetic and environmental factors that predispose to this disease.

Increased risk of appendectomy due to appendicitis after tonsillectomy in women: A longitudinal follow-up study using a national sample cohort

The purpose of this study was to evaluate the risk of appendectomy due to appendicitis after tonsillectomy in Koreans using national cohort data. Using the national cohort study from the Korean Health Insurance Review and Assessment Service, 1:4 matched tonsillectomy participants (9015) and control participants (36,060) were selected. The Cox-proportional hazard model was used. In this analysis, a crude and adjusted model for age, sex, income, region of residence, and the past medical histories of hypertension, diabetes mellitus, and dyslipidemia were used. For the subgroup analyses, the participants were divided as follows: children (≤14 years old) vs adolescents and adults (≥15 years old) and men vs women. The adjusted hazard ratio (HR) of tonsillectomy for appendectomy was 1.06 (95% confidence interval, CI = 0.89-1.27, P = .517). In the subgroup analysis, the HR was 1.03 (95% CI = 0.82-1.30, P = .804) in children and 1.10 (95% CI = 0.84-1.47, P = .468) in adolescents and adults. In another subgroup analysis, the HR was 0.89 (95% CI = 0.70-1.12, P = .314) in men and 1.39 (95% CI = 1.06-1.83, P = .018) in women. The risk of appendectomy was higher in the tonsillectomy group but only in women.

Genetic association and differential expression of PITX2 with acute appendicitis

Appendicitis affects 9% of Americans and is the most common diagnosis requiring hospitalization of both children and adults. We performed a genome-wide association study of self-reported appendectomy with 18,773 affected adults and 114,907 unaffected adults of European American ancestry. A significant association with appendectomy was observed at 4q25 near the gene PITX2 (rs2129979, p value = 8.82 × 10-14) and was replicated in an independent sample of Caucasians (59 affected, 607 unaffected; p value = 0.005). Meta-analysis of the associated variant across our two cohorts and cohorts from Iceland and the Netherlands (in which this association had previously been reported) showed strong cumulative evidence of association (OR = 1.12; 95% CI 1.09-1.14; p value = 1.81 × 10-23) and some evidence for effect heterogeneity (p value = 0.03). Eight other loci were identified at suggestive significance in the discovery GWAS. Associations were followed up by measuring gene expression across resected appendices with varying levels of inflammation (N = 75). We measured expression of 27 genes based on physical proximity to the GWAS signals, evidence of being targeted by eQTLs near the signals according to RegulomeDB (score = 1), or both. Four of the 27 genes (including PITX2) showed significant evidence (p values < 0.0033) of differential expression across categories of appendix inflammation. An additional ten genes showed nominal evidence (p value < 0.05) of differential expression, which, together with the significant genes, is more than expected by chance (p value = 6.6 × 10-12). PITX2 impacts morphological development of intestinal tissue, promotes an anti-oxidant response, and its expression correlates with levels of intestinal bacteria and colonic inflammation. Further studies of the role of PITX2 in appendicitis are warranted.

Familial Risk of Appendicitis: A Nationwide Population Study

OBJECTIVE

To investigate the familial risk of appendicitis in the general population.

STUDY DESIGN

A nationwide, cross-sectional study consisting of 24 349 599 Taiwan National Health Insurance beneficiaries in 2015 was conducted. Among them, 788 042 individuals had at least 1 first-degree relative with appendicitis. The familial relative risks (RRs) of appendicitis and familial transmission were estimated.

RESULTS

The overall RR (95% CI) of appendicitis in individuals with any affected first-degree relatives was 1.67 (1.64-1.71) compared with the general population. The RRs for individuals with an affected twin, sibling, offspring, and parent were 3.40 (2.66-4.35), 1.98 (1.92-2.04), 1.55 (1.51-1.59), and 1.54 (1.50-1.58), respectively. The RRs for individuals with 1, 2, 3 or more affected first-degree relatives were 1.65 (1.62-1.68), 2.63 (2.37-2.91), and 6.70 (4.22-10.63), respectively. Furthermore, there was an age-dependent trend of the RRs, with the greatest RR in the youngest group. The estimated familial transmission (genetic plus shared environmental contribution to the total phenotypic variance of appendicitis) was 23.2%.

CONCLUSION

Individuals with a family history of appendicitis have an increased risk of appendicitis. This risk is age-dependent and related to the genetic distance and numbers of affected relatives.

Association of meteorological factors with pediatric acute appendicitis in China: A 7-year retrospective analysis

Acute appendicitis (AA) affects between 7% and 8% of the world population and is one of the most common general surgical emergencies. The concept of seasonal patterns in the incidence of AA remains controversial. Thus, this study aimed to investigate whether meteorological factors are related to variations in the rate of pediatric AA cases at the Children's Hospital in Chongqing, China.In total, in this retrospective survey, 3436 children younger than 18 years who had been hospitalized with AA from January 1, 2008 to December 31, 2013 were enrolled, and the meteorological factors during this period were collected.Patients with AA showed a male/female ratio of 1.81:1; the highest incidence age ranged from 6 to 12 years old (P < .0001). The highest incidences of pediatric AA occurred in summer and autumn, with a peak in September and a trough in February. Pearson correlation analysis showed that the monthly mean temperature (r = 0.357, P = .001), monthly mean relative humidity (r = -0.357, P = .001), and monthly mean sunshine duration (r = 0.235, P = -0.031) were relatively weak correlated with pediatric AA. Multiple linear regression analysis indicated that pediatric AA occurrence was positively affected by monthly mean temperature (P < .0001) and negatively affected by monthly mean humidity (P < .0001) and monthly sum of sunshine (P < .0001), while monthly mean air pressure (P = .092), monthly wind speed (P = .143) and monthly precipitation (P = .297) were marginally associated with pediatric AA.Pediatric AA is associated with climatic factors. Specifically, pediatric AA is more likely related to the following meteorological conditions of: high temperature (20 °C-30 °C), low humidity, and less sunshine.

Appendectomy and Risk of Subsequent Diverticular Disease Requiring Hospitalization: A Population-Based Case-Control Study

BACKGROUND

Appendicitis and acute diverticulitis share clinical features and are both influenced by genetic and environmental factors. Appendectomy has been positively associated with diverticular disease in hospital-based case-control studies.

OBJECTIVE

The aim of the present study was to investigate, in a population-based setting, whether appendectomy, with or without appendicitis, is associated with an altered risk of hospitalization with diverticular disease.

DESIGN

This was a population-based case-control study.

SETTINGS

The study was based on national healthcare and population registers.

PATIENTS

We studied 41,988 individuals hospitalized between 2000 and 2010 with a first-time diagnosis of colonic diverticular disease and 413,115 matched control subjects.

MAIN OUTCOME MEASURES

The association between appendectomy with or without appendicitis and diverticular disease was investigated by conditional logistic regression, including a model adjusting for hospital use.

RESULTS

A total of 2813 cases (6.7%) and 19,037 controls (4.6%) had a previous record of appendectomy (appendectomy with acute appendicitis: adjusted OR = 1.31 (95% CI, 1.24-1.39); without appendicitis: adjusted OR = 1.30 (95% CI, 1.23-1.38)). Appendectomy was most strongly associated with an increased risk of diverticular disease within 1 year (with appendicitis: adjusted OR = 2.26 (95% CI, 1.61-3.16); without appendicitis: adjusted OR = 3.98 (95% CI, 2.71-5.83)), but the association was still present ≥20 years after appendectomy (with appendicitis: adjusted OR = 1.22 (95% CI, 1.12-1.32); without appendicitis: adjusted OR = 1.19 (95% CI, 1.10-1.28)).

LIMITATIONS

Detailed clinical information on the cases was not available. There were unmeasured potential confounders, such as smoking and dietary factors.

CONCLUSIONS

The findings are consistent with a hypothesis of appendectomy causing an increased risk of diverticular disease, for example, by affecting the mucosal immune system or the gut microbiome. However, several other mechanisms may contribute to, or account for, the positive association, including a propensity for abdominal pain increasing the risk of both the exposure and the outcome. See Video Abstract at http://links.lww.com/DCR/A604.

Familial history aggregation on acute appendicitis

Appendectomy is the most commonly performed surgical procedure, affecting 1%-8% of the paediatric population, with a total 7% lifetime risk, most likely in adolescents and young adults.A case of familial aggregation was reported in our hospital in a family composed of nine siblings from which six of them (66.6%) had been treated of acute appendicitis, five of them in our centre.Many factors have been described as predisposing to appendicitis. Several studies have highlighted the influence of genes in the evolution of this disease and its severity, demonstrating a relative risk increase by three when family history is present.Family history of acute appendicitis is an important factor to be taken into consideration during the medical interview. Clinicians attempting to fine-tune their diagnostic accuracy when patients present with acute abdominal pain should inquire about family history of appendicitis.

Sequence variant at 4q25 near PITX2 associates with appendicitis

Appendicitis is one of the most common conditions requiring acute surgery and can pose a threat to the lives of affected individuals. We performed a genome-wide association study of appendicitis in 7,276 Icelandic and 1,139 Dutch cases and large groups of controls. In a combined analysis of the Icelandic and Dutch data, we detected a single signal represented by an intergenic variant rs2129979 [G] close to the gene PITX2 associating with increased risk of appendicitis (OR = 1.15, P = 1.8 × 10-11). We only observe the association in patients diagnosed in adulthood. The marker is close to, but distinct from, a set of markers reported to associate with atrial fibrillation, which have been linked to PITX2. PITX2 has been implicated in determination of right-left symmetry during development. Anomalies in organ arrangement have been linked to increased prevalence of gastrointestinal and intra-abdominal complications, which may explain the effect of rs2129979 on appendicitis risk.

The Association Between Ventriculo-Peritoneal Shunt and Acute Appendicitis in Patients with Traumatic Brain Injury: A 14-Year, Population-Based Study

OBJECTIVE

The association between preexisting ventriculoperitoneal (VP) shunt and the risk of new-onset acute appendicitis in patients with traumatic brain injury (TBI) is not well established. The aim of the present study was to determine the relationships between VP shunt and acute appendicitis in patients with TBI.

METHODS

A longitudinal cohort study matched by a propensity score in patients with TBI with (4781 patients) or without (9562 patients) VP shunt was conducted using the National Health Insurance Research Database in Taiwan between January 1993 and December 2013.

RESULTS

The main outcome studied was diagnosis of acute appendicitis. The cumulative probability of acute appendicitis was not different between these 2 groups (P = 0.6244). A Cox model showed central nervous system (CNS) infection to be an independent predictor of acute appendicitis with an adjusted hazard ratio of 2.98. Patients with TBI with both a VP shunt and a CNS infection had a greater risk of developing new-onset acute appendicitis (hazard ratio 4.25; 95% confidence interval 1.84-9.81) compared patients with TBI without a VP shunt or CNS infection.

CONCLUSIONS

We concluded that VP shunt is not a risk factor in the development of appendicitis in patients with TBI. Patients with TBI with a shunt and a CNS infection may have a greater risk of developing acute appendicitis. Therefore, care in avoiding CNS infection is a key for the prevention acute appendicitis in this patient population.

Pediatric appendicitis: state of the art review

Appendicitis is a common cause of abdominal pain in children. The diagnosis and treatment of the disease have undergone major changes in the past two decades, primarily as a result of the application of an evidence-based approach. Data from several randomized controlled trials, large database studies, and meta-analyses have fundamentally affected patient care. The best diagnostic approach is a standardized clinical pathway with a scoring system and selective imaging. Non-operative management of simple appendicitis is a reasonable option in selected cases, with the caveat that data in children remain limited. A minimally invasive (laparoscopic) appendectomy is the current standard in US and European children's hospitals. This article reviews the current 'state of the art' in the evaluation and management of pediatric appendicitis.

Incidence of appendicitis according to region of origin in first- and second-generation immigrants and adoptees in Sweden. A cohort follow-up study

BACKGROUND

Geographic variations in incidence of appendicitis and proportion of perforations suggest environmental or genetic etiological factors. We study incidence of appendicitis and proportion of perforations according to geographical origin in immigrants and international adoptees in Sweden.

METHODS

A cohort of 11,557,566 Swedish residents - 277,104 first- and 377,773 second-generation immigrants and 57,304 adoptees - was followed from 1988 till 2010. Differences in proportion of operation for perforated appendicitis and negative appendectomy and standardized incidence ratios (SIR) of perforated and non-perforated appendicitis associated with geographic origin was analyzed.

RESULTS

High incidence rates are seen in first- and second-generation immigrants from South America for perforated (SIR 1.58 and 1.81, respectively) and non-perforated appendicitis (SIR 1.18 and 1.22, respectively), and in adoptees from South America for non-perforated appendicitis (SIR 1.07). Low incidence rates are seen for perforated appendicitis in first-generation immigrants and adoptees from Asia (SIR 0.74 and 0.56, respectively), and for non-perforated appendicitis in immigrants from Africa and Asia (SIR 0.69 and 0.76 in first-generation, 0.51 and 0.74 in second-generation, respectively) and in adoptees from Asia (SIR 0.71). A high proportion of perforated appendicitis is associated with a low incidence rate of non-perforated appendicitis but no increase in the incidence rate of perforated appendicitis.

CONCLUSIONS

The association of different incidence of appendicitis with geographic origin which remains over generations and is seen in adoptees suggest genetic etiologic factors. The proportion of perforation can be high without an increased incidence rate of perforation and is therefore an imperfect indicator of quality of care.

Polymorphisms in the IL-6 and IL-6R receptor genes as new diagnostic biomarkers of acute appendicitis: a study on two candidate genes in pediatric patients with acute appendicitis

Background

Acute appendicitis (AA) (OMIM: 107700) is an inflammatory disease which is characterized by appendiceal inflammation. Genetic and environmental factors contribute to the development of AA. Especially, multiple genetic factors appear to be promising in the explanation of etiopathogenesis of AA. IL-6 (Interleukin-6) is an inflammatory cytokine and IL-6 receptor (IL-6R) plays an important role in the immune response. IL-6 (-572G/C rs1800796) and IL-6R (1:G.154448302 T > C rs7529229) gene polymorphisms may have an impact on cytokine production, immune response and these gene polymorphisms may be used as inflammatory markers in the diagnosis of appendicitis.

Method

A total of 75 children with appendicitis, and 75 healthy children were included in the study. DNA extracts were obtained from peripheral lymphocytes. Single-nucleotide polymorphisms (SNPs) were analysed using an automated SYBR® Green RT-PCR system in pediatric patients with appendicitis (n = 75) and healthy controls (n = 75).

Results

The allele and genotype frequencies for IL-6 rs1800796 and IL-6R rs7529229 polymorphisms were not different between the study groups (p > 0.05). Any statistically significant differences as for age, sex and other laboratory factors were not detected between the patients with appendicitis for genotype-allele frequencies (p > 0.05). Still in analyses performed to determine correlations among age, and gender of the patients, routine laboratory parameters and allele-genotype frequencies, a statistically significant intergroup difference was not detected. Genotype and allele frequencies were consistent with Hardy-Weinberg equilibrium (HWE) in all groups.

Discussion

This is the first study to investigate the effects of functional two polymorphisms on IL-6 and IL-6R genes in a pediatric patient group with AA risk. With this study we investigated the contribution of IL-6 (-572G/C rs1800796) and IL-6R (1:G.154448302 T > C rs7529229) polymorphisms on pathogenesis, and severity of AA in pediatric patients with AA: These results will guide further genetic researches to be performed on the role of IL-6 and IL-6R in AA.

Conclusions

Given the putative biological importance of this SNPs, these emerging data can provide a new foundation to stimulate future debate and genetic investigations of AA, focusing on new molecular mechanisms such as other IL gene polymorphisms, particularly in accessible peripheral tissues for novel molecular diagnostics for appendicitis.

Acute appendicitis: modern understanding of pathogenesis, diagnosis, and management

Acute appendicitis is one of the most common abdominal emergencies worldwide. The cause remains poorly understood, with few advances in the past few decades. To obtain a confident preoperative diagnosis is still a challenge, since the possibility of appendicitis must be entertained in any patient presenting with an acute abdomen. Although biomarkers and imaging are valuable adjuncts to history and examination, their limitations mean that clinical assessment is still the mainstay of diagnosis. A clinical classification is used to stratify management based on simple (non-perforated) and complex (gangrenous or perforated) inflammation, although many patients remain with an equivocal diagnosis, which is one of the most challenging dilemmas. An observed divide in disease course suggests that some cases of simple appendicitis might be self-limiting or respond to antibiotics alone, whereas another type often seems to perforate before the patient reaches hospital. Although the mortality rate is low, postoperative complications are common in complex disease. We discuss existing knowledge in pathogenesis, modern diagnosis, and evolving strategies in management that are leading to stratified care for patients.

Seasonal variations of acute appendicitis and nonspecific abdominal pain in Finland

AIM: To investigate whether seasonal changes had an effect on the incidence of acute appendicitis (AA) or nonspecific abdominal pain (NSAP).

METHODS: We carried out a national register study of all patients with a hospital discharge diagnosis of AA and acute NSAP in Finland. Data were analyzed for the whole country and correlated to seasonal and weather parameters (temperature, humidity). Moreover, additional sub-analyses were performed for five geographically different area of Finland.

RESULTS: The observation period spanned 21 years, with 186558 appendectomies, of which 137528 (74%) cases were reported as AA. The incidence of AA declined for 32% over the study period. The average incidence of the NSAP was 34/10000 per year. The mean annual temperature, but not relative humidity, showed clear geographical variations. The incidence of AA decreased significantly during the cold months of the year. No correlation was detected between temperature and incidence of NSAP. Humidity had a statistically significant impact on NSAP.

CONCLUSION: The incidence of acute appendicitis is declining in Finland. We detected a clear seasonality in the incidence of AA and NSAP.

Vegetables, fruit and risk of non-gallstone-related acute pancreatitis: a population-based prospective cohort study

OBJECTIVE

To examine the association of vegetable and fruit consumption with the risk of non-gallstone-related acute pancreatitis.

DESIGN

A population-based prospective cohort of 80,019 women and men, aged 46-84 years, completed a food-frequency questionnaire at baseline and was followed up for incidence of non-gallstone-related acute pancreatitis from 1 January 1998 to 31 December 2009. Participants were categorised into quintiles according to consumption of vegetables and consumption of fruit. Cox proportional hazards models were used to estimate RRs and 95% CIs.

RESULTS

In total, 320 incident cases (216 men and 104 women) with non-gallstone-related acute pancreatitis were identified during 12 years of follow-up (891,136 person-years). After adjustment for potential confounders, the authors observed a significant inverse linear dose-response association between vegetable consumption and risk of non-gallstone-related acute pancreatitis; every two additional servings per day were associated with 17% risk reduction (RR=0.83; 95% CI 0.70 to 0.98; p=0.03). Among participants consuming >1 drink of alcohol per day and among those with body mass index ≥25 kg/m2, the RR for the highest compared with the lowest quintile of vegetable consumption was 0.29 (95% CI 0.13 to 0.67) and 0.49 (95% CI 0.29 to 0.85), respectively. Fruit consumption was not significantly associated with the risk of non-gallstone-related acute pancreatitis; the RR comparing extreme quintiles of consumption was 1.20 (95% CI 0.81 to 1.78).

CONCLUSIONS

Vegetable consumption, but not fruit consumption, may play a role in the prevention of non-gallstone-related acute pancreatitis.

Effect of type of alcoholic beverage in causing acute pancreatitis

Background

The effect of different alcoholic beverages and drinking behaviour on the risk of acute pancreatitis has rarely been studied. The aim of this study was to investigate the effect of different types of alcoholic beverage in causing acute pancreatitis.

Methods

A follow-up study was conducted, using the Swedish Mammography Cohort and Cohort of Swedish Men, to study the association between consumption of spirits, wine and beer and the risk of acute pancreatitis. No patient with a history of chronic pancreatitis was included and those who developed pancreatic cancer during follow-up were excluded. Multivariable Cox proportional hazards models were used to estimate rate ratios.

Results

In total, 84 601 individuals, aged 46-84 years, were followed for a median of 10 years, of whom 513 developed acute pancreatitis. There was a dose–response association between the amount of spirits consumed on a single occasion and the risk of acute pancreatitis. After multivariable adjustments, there was a 52 per cent (risk ratio 1·52, 95 per cent confidence interval 1·12 to 2·06) increased risk of acute pancreatitis for every increment of five standard drinks of spirits consumed on a single occasion. The association weakened slightly when those with gallstone-related pancreatitis were excluded. There was no association between consumption of wine or beer, frequency of alcoholic beverage consumption including spirits, or average total monthly consumption of alcohol (ethanol) and the risk of acute pancreatitis.

Conclusion

The risk of acute pancreatitis was associated with the amount of spirits consumed on a single occasion but not with wine or beer consumption.

The role of high-mobility group box-1 (HMGB-1) in the management of suspected acute appendicitis: useful diagnostic biomarker or just another blind alley?

Acute abdominal pain is one of the most frequent reasons for admitting patients to the emergency department for surgical evaluation. A wide number of differential diagnoses are available and their pre-test likelihood ratio varies according to the patients' age, gender, duration of symptoms and overall clinical context. While many patients with abdominal pain do not need to be admitted to the hospital wards and even fewer need eventual surgical intervention, the diagnosis of acute appendicitis remains one of the most frequently entertained differential in patients with abdominal pain. In fact, surgery for appendicitis is one of the most frequently performed operations in the Western world. As the authors of the current study point out, the high mobility group box-1 protein (HMGB1) has been known for many years. The study demonstrates in a small pilot that there is a difference in expression of HMGB1 between those with and those without appendicitis. However, is this difference clinically important? Clinically relevant results can only be documented through larger studies comparing its use and expression levels in both healthy subjects, subjects with abdominal pain for other reasons, patients with 'clear-cut' (histopathologically confirmed) appendicitis and in the difficult subgroup of patients with suspected appendicitis and equivocal symptoms.