Gangrenous appendicitis in children: a prospective evaluation of definition, bacteriology, histopathology, and outcomes

Postoperative Antibiotics, Outcomes, and Resource Use in Children With Gangrenous Appendicitis

Importance

Gangrenous, suppurative, and exudative (GSE) findings have been associated with increased surgical site infection (SSI) risk and resource use in children with nonperforated appendicitis. Establishing the role for postoperative antibiotics may have important implications for infection prevention and antimicrobial stewardship.

Objective

To compare SSI rates in children with nonperforated appendicitis with GSE findings who did and did not receive postoperative antibiotics.

Design, Setting, and Participants

This was a retrospective cohort study using American College of Surgeons' National Surgical Quality Improvement Program (NSQIP)-Pediatric Appendectomy Targeted data from 16 hospitals participating in a regional research consortium. NSQIP data were augmented with operative report and antibiotic use data obtained through supplemental medical record review. Children with nonperforated appendicitis with GSE findings who underwent appendectomy between July 1, 2015, and June 30, 2020, were identified using previously validated intraoperative criteria. Data were analyzed from October 2022 to July 2023.

Exposure

Continuation of antibiotics after appendectomy.

Main Outcomes and Measures

Rate of 30-day postoperative SSI including both incisional and organ space infections. Complementary hospital and patient-level analyses were conducted to explore the association between postoperative antibiotic use and severity-adjusted outcomes. The hospital-level analysis explored the correlation between postoperative antibiotic use and observed to expected (O/E) SSI rate ratios after adjusting for differences in disease severity (presence of gangrene and postoperative length of stay) among hospital populations. In the patient-level analysis, propensity score matching was used to balance groups on disease severity, and outcomes were compared using mixed-effects logistic regression to adjust for hospital-level clustering.

Results

A total of 958 children (mean [SD] age, 10.7 [3.7] years; 567 male [59.2%]) were included in the hospital-level analysis, of which 573 (59.8%) received postoperative antibiotics. No correlation was found between hospital-level SSI O/E ratios and postoperative antibiotic use when analyzed by either overall rate of use (hospital median, 53.6%; range, 31.6%-100%; Spearman ρ = -0.10; P = .71) or by postoperative antibiotic duration (hospital median, 1 day; range, 0-7 days; Spearman ρ = -0.07; P = .79). In the propensity-matched patient-level analysis including 404 patients, children who received postoperative antibiotics had similar rates of SSI compared with children who did not receive postoperative antibiotics (3 of 202 [1.5%] vs 4 of 202 [2.0%]; odds ratio, 0.75; 95% CI, 0.16-3.39; P = .70).

Conclusions and Relevance

Use of postoperative antibiotics did not improve outcomes in children with nonperforated appendicitis with gangrenous, suppurative, or exudative findings.

Differences in isolated bacteria between perforated and non-perforated appendicitis: an analysis of 680 consecutive appendicectomies in a single institution

PURPOSE

Escherichia coli and Bacteroides species are the most frequently detected species in ascites in perforated appendicitis and are generally sensitive to non-empiric cephalosporins like cefazolin or cefmetazole. However, monotherapy with such antibiotics is mostly insufficient for perforated appendicitis. To investigate this issue, this study aimed to compare bacterial floras in ascites culture between perforated and non-perforated appendicitis.

METHODS

Ascites culture results in perforated and non-perforated appendicitis cases were analyzed using a departmental database. The duration of symptoms before surgery, pre-surgical white blood cell count, C-reactive protein value, postsurgical length of stay, length of antibiotic treatment, and the rate of using second-line antibiotics or complications were also compared.

RESULTS

A total of 608 and 72 cases of non-perforated and perforated appendicitis were included. Escherichia coli and Bacteroides species were the dominant bacteria in both conditions. However, the total proportions of Pseudomonas aeruginosa, Streptococcus anginosus group, and Enterococcus group were significantly higher in perforated appendicitis than in non-perforated appendicitis.

CONCLUSION

Pseudomonas aeruginosa, Streptococcus anginosus group, and Enterococcus group have better susceptibility to penicillin-based empiric antibiotics than cephalosporins. The abundance of these bacteria might explain why non-empiric cephalosporins are not effective in perforated appendicitis and the superiority of penicillin-based empiric antibiotics.

Systematic Review of Definitions and Outcome Measures for Postoperative Ileus and Return of Bowel Function after Abdominal Surgery in Children

This review aims to objectify which definitions and outcome measures are used for the return of bowel function and postoperative ileus in children. PubMed and Embase were systematically searched from inception to December 17, 2020. Prospective studies conducted in children (aged 0-18 years) undergoing gastrointestinal surgery which reported on definitions and/or outcome measures for post-operative ileus or return of bowel function were evaluated. Definitions and outcome measures were extracted. From 4,027 references, 71 articles were included. From the 17 articles mentioning postoperative ileus, 8 (47%) provided a definition. In total, 34 outcome measures were used and 12 were unique. "Abdominal distension" was the most reported (41%) measure. In 41%, the outcome measures only described the return of gastric motility, while 18% described the return of intestinal motility. The return of bowel function was mentioned in 67 articles, none provided a definition. In total, 133 outcome measures were used and 37 were unique. Time to oral intake was the most reported (14%) measure. In 49%, the outcome measures only described the return of gastric motility, while 10% described the return of intestinal motility. High variation in definitions and outcome measures has limited the generalizability of research into postoperative bowel function in children. Without standardization, it will be impossible to compare research results and evaluate treatments. In children, the return of gastric motility seemingly should get more focus compared to adults. Therefore, we believe that a definition of postoperative ileus with an accompanying core outcome set, developed by a multidisciplinary team, specifically for children is required.

Association of Gangrenous, Suppurative, and Exudative Findings With Outcomes and Resource Utilization in Children With Nonperforated Appendicitis

Importance

The clinical significance of gangrenous, suppurative, or exudative (GSE) findings is poorly characterized in children with nonperforated appendicitis.

Objective

To evaluate whether GSE findings in children with nonperforated appendicitis are associated with increased risk of surgical site infections and resource utilization.

Design, Setting, and Participants

This multicenter cohort study used data from the Appendectomy Targeted Database of the American College of Surgeons Pediatric National Surgical Quality Improvement Program, which were augmented with operative report data obtained by supplemental medical record review. Data were obtained from 15 hospitals participating in the Eastern Pediatric Surgery Network (EPSN) research consortium. The study cohort comprised children (aged ≤18 years) with nonperforated appendicitis who underwent appendectomy from July 1, 2015, to June 30, 2020.

Exposures

The presence of GSE findings was established through standardized, keyword-based audits of operative reports by EPSN surgeons. Interrater agreement for the presence or absence of GSE findings was evaluated in a random sample of 900 operative reports.

Main Outcomes and Measures

The primary outcome was 30-day postoperative surgical site infections (incisional and organ space infections). Secondary outcomes included rates of hospital revisits, postoperative abdominal imaging, and postoperative length of stay. Multivariable mixed-effects regression was used to adjust measures of association for patient characteristics and clustering within hospitals.

Results

Among 6133 children with nonperforated appendicitis, 867 (14.1%) had GSE findings identified from operative report review (hospital range, 4.2%-30.2%; P < .001). Reviewers agreed on presence or absence of GSE findings in 93.3% of cases (weighted κ, 0.89; 95% CI, 0.86-0.92). In multivariable analysis, GSE findings were associated with increased odds of any surgical site infection (4.3% vs 2.2%; odds ratio [OR], 1.91; 95% CI, 1.35-2.71; P < .001), organ space infection (2.8% vs 1.1%; OR, 2.18; 95% CI, 1.30-3.67; P = .003), postoperative imaging (5.8% vs 3.7%; OR, 1.70; 95% CI, 1.23-2.36; P = .002), and prolonged mean postoperative length of stay (1.6 vs 0.9 days; rate ratio, 1.43; 95% CI, 1.32-1.54; P < .001).

Conclusions and Relevance

In children with nonperforated appendicitis, findings of gangrene, suppuration, or exudate are associated with increased surgical site infections and resource utilization. Further investigation is needed to establish the role and duration of postoperative antibiotics and inpatient management to optimize outcomes in this cohort of children.

Diagnostic Value of Clinical Prediction Scores for Acute Appendicitis in Children Younger than 4 Years

INTRODUCTION

 Acute appendicitis can be difficult to diagnose, especially in children < 4 years old. The aim of the present study was to assess the diagnostic value of Alvarado score (AS), appendicitis inflammatory response (AIR) score, and pediatric appendicitis score (PAS) in children younger than 4 years.

MATERIALS AND METHODS

 All children younger than 4 years who underwent appendicectomy between 2005 and 2019 were included retrospectively. The diagnostic performance of the scores was analyzed using the area under the receiver-operating characteristic (ROC) curve and by calculating the diagnostic performances at optimal criterion value cutoff points.

RESULTS

 In this study, 100 children were included (58 boys and 42 girls) with a median age of 39.5 (12-47) months. Ninety children were diagnosed with pathologically proven acute appendicitis. The area under ROC curve of AS was 0.73, AIR score was 0.79, and PAS was 0.69 (p > 0.05, respectively). In children with low risk of acute appendicitis, negative predictive values were 75.0% for AS, 50.0% for AIR score, and 66.7% for PAS (p < 0.05, respectively). The positive predictive values in children with high risk of acute appendicitis were of 92.7% for AS, 92.6% for AIR score, and 93.6% for PAS (p > 0.05, respectively). AS, AIR score, and PAS plus positive ultrasonography have 0.58, 0.49, and 0.88 area under ROC curve.

CONCLUSION

 The three scores can be of assistance in the suspicion of acute appendicitis. PAS markedly improved combined with positive ultrasonography, but none can be used in setting the diagnosis of acute appendicitis in young children.

Appendiceal Intraluminal Gas: A CT Marker for Gangrenous Appendicitis

Introduction

This manuscript aims to investigate the amount of intraluminal gas in acute, nonperforated appendicitis identified on computed tomography (CT) in diagnosing gangrenous appendicitis.

Methods

This is a retrospective observational, case-control study with consecutive data collected at a tertiary institution over a two-year period, of patients with CT-diagnosed acute appendicitis who subsequently went on for surgery within 48 hours. Patients who were less than 16 years old, who had an interval between CT and surgery of more than 48 hours, or with CT evidence of appendiceal perforation were excluded. Images were independently assessed by 3 radiologists for intraluminal gas, and the results were then correlated with reference standards obtained from surgical and histopathology reports for the diagnosis of nongangrenous versus gangrenous appendicitis. The sensitivity, specificity, and predictive values of CT intraluminal gas in gangrenous appendicitis were calculated.

Results

Our study identified 93 patients with nonperforated acute appendicitis who underwent surgery within the stated timeframe. Intraluminal gas in the appendix was identified in 26 patients (28%), of which 54% had macroscopic and/or microscopic evidence of gangrenous appendicitis. This is in contrast to the subgroup of patients who did not have intraluminal gas (72%), of which only 33% had gangrenous appendicitis. The specificity of intraluminal gas for gangrenous appendicitis is 79%, with a negative predictive value of 86% and likelihood ratio of 1.85.

Conclusion

In cases of established acute appendicitis, the presence of intraluminal gas is a moderately specific sign for gangrenous complication. This is worth reporting as it can help prognosticate and triage patients accordingly, for a timelier surgical management and a better outcome.

Controversy in the classification of appendicitis and utilization of postoperative antibiotics

BACKGROUND

There is wide variability and considerable controversy regarding the classification of appendicitis and the need for postoperative antibiotics. This study aimed to assess interrater agreement with respect to the classification of appendicitis and its influence on the use of postoperative antibiotics amongst surgeons and surgical trainees.

METHODS

A survey comprising 15 intraoperative images captured during appendectomy was distributed to surgeons and surgical trainees. Participants were asked to classify severity of disease (normal, inflamed, purulent, gangrenous, perforated) and whether they would prescribe postoperative antibiotics. Statistical analysis included percent agreement, Krippendorff's alpha for interrater agreement, and logistic regression.

RESULTS

In total, 562 respondents completed the survey: 206 surgical trainees, 217 adult surgeons, and 139 pediatric surgeons. For classification of appendicitis, the statistical interrater agreement was highest for categorization as gangrenous/perforated versus nongangrenous/nonperforated (Krippendorff's alpha = 0.73) and lowest for perforated versus nonperforated (Krippendorff's alpha = 0.45). Fourteen percent of survey respondents would administer postoperative antibiotics for an inflamed appendix, 44% for suppurative, 75% for gangrenous, and 97% for perforated appendicitis. Interrater agreement of postoperative antibiotic use was low (Krippendorff's alpha = 0.28). The only significant factor associated with postoperative antibiotic utilization was 16 or more years in practice.

CONCLUSIONS

Surgeon agreement is poor with respect to both subjective appendicitis classification and objective utilization of postoperative antibiotics. This survey demonstrates that a large proportion (59%) of surgeons prescribe antibiotics after nongangrenous or nonperforated appendectomy, despite a lack of evidence basis for this practice. These findings highlight the need for further consensus to enable standardized research and avoid overtreatment with unnecessary antibiotics.

Associations of hair cortisol concentrations with paediatric appendicitis

The pathogenesis of paediatric appendicitis is still an enigma. In recent years, it has become more evident that our inherent immunological responses affect the trajectory of the disease course. Long-term stress has an impact on our immune system; however, it is practically and ethically challenging to prospectively track blood measurements of cortisol-levels in asymptomatic children should an acute appendicitis episode develop. The aim of this case–control study was therefore to evaluate the effect of increased stress measured as historical imprints in hair (hair cortisol concentrations [HCC]), on the risk of developing appendicitis and complicated appendicitis. 51 children (aged < 15 years) with appendicitis (34 with complicated appendicitis), were compared to 86 healthy controls. HCC reflecting the activity of the HPA-axis 0–3 and 4–6 months prior to sampling was evaluated and compared between groups as well as between the two measurements of each study subject. In the univariate analysis with both cases and controls, an increase in HCC between the measurement timepoints was associated with a substantial increase in risk of appendicitis (OR 7.52 [95% CI 2.49–22.67], p = 0.001). This increased risk remained in the multivariate analysis after adjustment for age, sex and season (aOR OR 10.76 [95%CI 2.50–46.28], p  = 0.001). When comparing the cases of uncomplicated and complicated appendicitis through a multivariate analysis, adjusted for age and sex, the children with an increased HCC prior to appendicitis had a substantial and statistically significant increase in risk of complicated appendicitis (aOR 7.86 [95% CI 1.20–51.63], p = 0.03). Biological stress, measured as an increase in HCC, seems to be associated with an increased risk of paediatric appendicitis and a more complicated disease course.

Clinical Prediction Scores for Pediatric Appendicitis

INTRODUCTION

 The rate of misdiagnosis of appendicitis in children is a challenge and clinical prediction scores could be part of the solution. However, the pediatric appendicitis score (PAS) and the Alvarado score have shown disappointing diagnostic accuracy in pediatric validation studies, while the appendicitis inflammatory response (AIR) score and the novel pediatric appendicitis risk calculator (pARC) have not yet been validated thoroughly. Therefore, the aim of the present study was to evaluate these four prediction scores prospectively in children with suspected appendicitis.

MATERIALS AND METHODS

 A prospective study was conducted over a 2-year period. All patients <15 years with suspected appendicitis were eligible for inclusion. The four prediction scores were compared regarding predictive values, receiver operating characteristics (ROC) curves, decision curve analysis, and clinical outcome.

RESULTS

 Of the 318 patients included, 151 (47 %) patients had appendicitis. The AIR score and the pARC had substantially higher specificity and positive predictive value, and lower rate of false positives (7% and 2%), than the PAS and Alvarado score (36 and 28%, p < 0.001). Across the different gender and age groups, the AIR score and the pARC generally had fewer false positives than the PAS and Alvarado score. There were no significant differences in sensitivity, negative predictive values, rates of missed appendicitis, or ROC curve analysis. In decision curve analysis, the AIR score and the pARC outperformed the PAS and Alvarado score at most threshold probabilities.

CONCLUSION

 The AIR score and the pARC are superior to the PAS and Alvarado score in diagnosing children with suspected appendicitis.

[Impact of COVID-19 on the presentation and course of acute appendicitis in paediatrics]

Introducción

La apendicitis aguda (AA) es la patología quirúrgica urgente más frecuente en pediatría. La pandemia por la COVID-19 ha generado un descenso en las consultas a urgencias, pudiendo conllevar un retraso en la atención sanitaria y un aumento en la gravedad de las patologías. El objetivo es analizar la tasa de AA complicadas durante la pandemia, en comparación con el mismo periodo del año anterior.

Material y métodos

Estudio retrospectivo observacional de cohortes unicéntrico que incluyó a pacientes menores de 14 años atendidos en urgencias con diagnóstico de AA durante los meses de marzo a mayo de 2019 (no pandemia) y 2020 (pandemia).

Resultados

Se incluyeron 90 pacientes (41 en no pandemia y 49 en pandemia). No se encontraron diferencias en el tiempo desde el inicio de la clínica hasta la consulta en urgencias entre los dos periodos (37 h vs. 38 h, p = 0,881), pero sí en el tiempo desde la llegada a urgencias hasta la intervención quirúrgica (7:00 h vs. 10:30 h; p = 0,004). La diferencia se acentuó al comparar el mes de marzo con abril-mayo de 2020 (6 h vs. 12 h; p = 0,001). No se observaron diferencias significativas en la tasa de AA complicadas en el diagnóstico intraoperatorio (35% vs. 33%; p = 0,870) ni anatomopatológico (35% vs. 48%; p = 0,222), ni tampoco en el número de complicaciones postoperatorias, duración de ingreso y reingresos. Se objetivó un aumento del diagnóstico anatomopatológico de AA con periapendicitis (47% vs. 81%; p = 0,001).

Conclusión

Durante la pandemia se observó una demora desde la llegada a urgencias hasta la intervención quirúrgica en niños diagnosticados de AA. Esta demora se tradujo en un incremento del diagnóstico de AA evolucionadas histológicamente, pero sin objetivarse un aumento de las complicaciones de la enfermedad.

Safety assessment of open appendectomies for complicated acute appendicitis in children: a comparison of trainees and specialists

PURPOSE

The aim of this study was to compare the outcome of children with complicated acute appendicitis (CAA) who underwent open appendectomy (OA) performed either by trainees under the direct supervision of an SPS, or an SPS.

METHODS

Two hundred thirty eight patients with CAA were reviewed operated on either by a junior trainee (JT) or a senior trainee (ST) under the direct supervision of an SPS or by an SPS. The outcome measures were the overall rate of complications, operative time (OT), length of hospital stay (LHS) and 30-day readmission rate.

RESULTS

No statistical differences were observed between the three groups regarding the overall complication rates and 30-day readmission rate. Although, no statistical differences were observed in the mean OT between the three groups, the mean OT for perforated appendicitis (PA) performed by JTs was significantly longer than when performed by SPSs (p 0.012). Furthermore, there was a statistically significant difference between JTs and SPSs in terms of LHS for patients with PA (p 0.028).

CONCLUSION

This study suggests that no statistical differences were observed between the supervised trainees and SPSs regarding the overall complication rate and 30-readmission rate when they performed OA for GA or PA except of a longer OT and LHS for PA performed by JTs.

Evaluation of concordance among surgeons and pathologists regarding the diagnosis and classification of acute appendicitis in children

Acute appendicitis is the most frequent urgent abdominal surgical pathology in children. Therapeutic decisions in patients who have undergone an appendectomy are made based on the macroscopic findings at the moment of surgery. There is high variability between surgical and histopathological findings.

METHOD

Concordance among surgeons and pathologists regarding the diagnosis and classification of acute appendicitis was assessed in children who have undergone an appendectomy. Surgical site infection (SSI) incidence was measured for both the surgical and pathological classification.

RESULTS

The statistical analysis included 1092 children. The pathologists confirmed the presence of appendicitis in 90.4% of the patients. Concordance in the diagnosis of appendicitis among surgeons and pathologists was weak (kappa 0.57), while concordance in the classification of perforated or non-perforated appendicitis was moderate (kappa 0.7). There were no significant differences in these findings determined by the surgeons' experience or the open or laparoscopic approach. In the discordant group of 70 patients in which the surgeon classified the appendicitis as non-perforated but the pathologist classified as perforated, just one patient developed an intra-abdominal abscess.

CONCLUSIONS

The classification of appendicitis as perforated or non-perforated shows moderate concordance between the surgical and histopathological diagnosis. This concordance is not determined by the surgeons' experience or the surgical approach.

TYPE OF STUDY

Diagnostic Test LEVEL OF EVIDENCE: Level II.

Sensibilidad antimicrobiana en aislamientos de líquido peritoneal de niños intervenidos por abdomen agudo e infección intraabdominal

Introducción. La apendicitis aguda es causa frecuente de infección intraabdominal en pediatría. La elección del antibiótico se basa en los hallazgos quirúrgicos macroscópicos, el criterio médico, las guías locales o internacionales y, en pocas ocasiones, en el resultado de los aislamientos bacterianos en cultivos de líquido peritoneal y las tasas locales de resistencia. Se analizaron la frecuencia y la sensibilidad microbiológica de los cultivos de muestras de líquido peritoneal de pacientes de un mes a 16 años de edad con manejo quirúrgico por abdomen agudo con sospecha de infección intraabdominal. Materiales y métodos. Se llevó a cabo un estudio prospectivo de cohorte con análisis de las historias clínicas y de resultados de laboratorio de niños sometidos a cirugía por abdomen agudo, en la que el cirujano tomó muestra del líquido peritoneal para la tipificación y determinación de los perfiles de sensibilidad de los microorganismos aislados. Los datos se analizaron con el programa Stata™, versión15.0. Resultados. Se identificaron 303 casos, de los cuales el 93,6 % recibió profilaxis antibiótica con ampicilina-sulbactam y clindamicina-amikacina. El 95,3 % de los procedimientos fueron apendicectomías. Se tomó cultivo del 50 % de las apendicitis perforadas. Se aislaron 48 microorganismos; el más frecuente (2,7 %) fue Escherichia coli positiva para BLEE. El 100 % de los microorganismos resultaron ser sensibles a la amikacina, el 97,2 % al meropenem, y el 94,4 %, a la ciprofloxacina, el cefepime y el ceftazidime. La resistencia más frecuente (37,1 %) fue contra la combinación de ampicilina y sulbactam, en los gérmenes Gram negativos. Discusión. La evaluación de la sensibilidad antimicrobiana de los aislamientos de líquido peritoneal de los procedimientos quirúrgicos en pediatría, es una buena práctica clínica que orienta al cirujano en la adecuada selección del esquema antibiótico y, además, disminuye el riesgo de falla terapéutica temprana y la posibilidad de mayor resistencia o complicaciones infecciosas.

Postoperative Outcomes of Patients With Nonperforated Gangrenous Appendicitis: A National Multicenter Prospective Cohort Analysis

BACKGROUND

Controversy exists regarding the use of postoperative antibiotics for nonperforated gangrenous appendicitis.

OBJECTIVE

The aim of this study was to evaluate the rate of postoperative infectious complications and the effect of postoperative antibiotic use among patients with nonperforated gangrenous appendicitis.

DESIGN

This was a prospective cohort study conducted during 2 months.

SETTINGS

A national multicenter observational study was conducted in 62 Dutch hospitals.

PATIENTS

All of the consecutive patients who had surgery for suspected acute appendicitis were included. Patients were excluded if no appendectomy was performed or appendectomy was performed for pathology other than acute appendicitis.

MAIN OUTCOMES MEASURES

Type of appendicitis was categorized as phlegmonous, gangrenous, or perforated. The primary end point was the rate of infectious complications (intra-abdominal abscess and surgical site infection) within 30 days after appendectomy. Univariable and multivariable logistic regression analyses were performed to identify predictors of infectious complications.

RESULTS

A total of 1863 patients were included: 1321 (70.9%) with phlegmonous appendicitis, 181 (9.7%) with gangrenous appendicitis, and 361 (19.4%) with perforated appendicitis. Infectious complications were more frequent in patients with gangrenous versus phlegmonous appendicitis (7.2% vs 3.8%; p = 0.03). This association was no longer statistically significant in multivariable analysis (OR = 1.09 (95% CI, 0.49-2.44)). There was no significant difference in infectious complications between ≤24 hours (n = 57) of postoperative antibiotics compared with >24 hours (n = 124; 3.6% vs 8.9%; p = 0.35) in patients with gangrenous appendicitis.

LIMITATIONS

Possible interobserver variability in the intraoperative classification of appendicitis was a study limitation.

CONCLUSIONS

Patients with nonperforated gangrenous appendicitis are at higher risk of infectious complications than patients with phlegmonous appendicitis, yet gangrenous disease is not an independent risk factor. Postoperative antibiotic use over 24 hours was not associated with decreased infectious complications. See Video Abstract at http://links.lww.com/DCR/A1000. RESULTADOS POSTOPERATORIOS DE PACIENTES CON APENDICITIS GANGRENOSA NO PERFORADA: UN ANÁLISIS DE COHORTE PROSPECTIVO MULTICÉNTRICO NACIONAL:: Existe controversia sobre el uso de antibióticos postoperatorios para la apendicitis gangrenosa no perforada.El objetivo de este estudio fue evaluar la tasa de complicaciones infecciosas postoperatorias y el efecto del uso de antibióticos postoperatorios en pacientes con apendicitis gangrenosa no perforada.Estudio de cohorte prospectivo realizado durante dos meses.Estudio observacional multicéntrico nacional en 62 hospitales holandeses.Todos los pacientes consecutivos sometidos a cirugía por sospecha de apendicitis aguda. Los pacientes fueron excluidos si no se realizó una apendicectomía o si se realizó una apendicectomía para otra patología que no fuera la apendicitis aguda.El tipo de apendicitis se clasificó como flegmonosa, gangrenosa o perforada. El criterio de valoración primario fue la tasa de complicaciones infecciosas (absceso intraabdominal e infección en el sitio quirúrgico) dentro de los 30 días posteriores a la apendicectomía. Se realizaron análisis de regresión logística univariables y multivariables para identificar predictores de complicaciones infecciosas.Se incluyeron un total de 1863 pacientes: 1321 (70,9%) con apendicitis flegmonosa, 181 (9,7%) con apendicitis gangrenosa y 361 (19,4%) con apendicitis perforada. Las complicaciones infecciosas fueron más frecuentes en pacientes con apendicitis gangrenosa frente a flegmonosa (7,2% frente a 3,8%, p = 0,03). Esta asociación ya no fue estadísticamente significativa en el análisis multivariable (OR 1,09; IC del 95%: 0,49 a 2,44). No hubo diferencias significativas en las complicaciones infecciosas entre ≤ 24 h (n = 57) de los antibióticos postoperatorios en comparación con> 24 h (n = 124) (3,6% vs. 8,9%, p = 0,35) en pacientes con apendicitis gangrenosa.Posible variabilidad interobservador en la clasificación intraoperatoria de la apendicitis.Los pacientes con apendicitis gangrenosa no perforada tienen un mayor riesgo de complicaciones infecciosas que los pacientes con apendicitis flegmonosa, aunque la enfermedad gangrenosa no es un factor de riesgo independiente. El uso de antibióticos postoperatorios durante 24 horas no se asoció con una disminución de las complicaciones infecciosas. Vea el Resumen del Video en http://links.lww.com/DCR/A1000.

Gangrenous appendicitis: No longer complicated

BACKGROUND

Appendicitis presents on a spectrum ranging from inflammation to gangrene to perforation. Studies suggest that gangrenous appendicitis has lower postoperative infection rates relative to perforated cases. We hypothesized that gangrenous appendicitis could be successfully treated as simple appendicitis, reducing length of stay (LOS) and antibiotic usage without increasing postoperative infections.

METHODS

In February 2016, we strictly defined complex appendicitis as a hole in the appendix, extraluminal fecalith, diffuse pus or a well-formed abscess. We switched gangrenous appendicitis to a simple pathway and reviewed all patients undergoing laparoscopic appendectomy for 12 months before (Group 1) and 12 months after (Group 2) the protocol change. Data collected included demographics, appendicitis classification, LOS, presence of a postoperative infection, and 30-day readmissions.

RESULTS

Patients in Group 1 and Group 2 were similar, but more cases of simple appendicitis occurred in Group 2. Average LOS for gangrenous appendicitis patients decreased from 2.5 to 1.4 days (p < 0.001) and antibiotic doses decreased from 5.2 to 1.3 (p < 0.001). Only one gangrenous appendicitis patient required readmission, and one patient in each group developed a superficial infection; there were no postoperative abscesses.

CONCLUSIONS

Gangrenous appendicitis can be safely treated as simple appendicitis without increasing postoperative infections or readmissions.

TYPE OF STUDY

Prognosis study.

LEVEL OF EVIDENCE

Level II.

Can ultrasound reliably identify complicated appendicitis in children?

BACKGROUND

The ability of ultrasound to identify specific features relevant to nonoperative management of pediatric appendicitis, such as the presence of complicated appendicitis (CA) or an appendicolith, is unknown. Our objective was to determine the reliability of ultrasound in identifying these features.

METHODS

We performed a retrospective study of children who underwent appendectomy after an ultrasound at four children's hospitals. Imaging, operative, and pathology reports were reviewed. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of ultrasound for identifying CA based on pathology and intraoperative findings and an appendicolith based on pathology were calculated. CA was defined as a perforation of the appendix. Equivocal ultrasounds were considered as not indicating CA.

RESULTS

Of 1027 patients, 77.5% had simple appendicitis, 16.2% had CA, 5.4% had no evidence of appendicitis, and 15.6% had an appendicolith. Sensitivity and specificity of ultrasound for detecting CA based on pathology were 42.2% and 90.4%; the PPV and NPV were 45.8% and 89.0%, respectively. Sensitivity and specificity of ultrasound for detecting CA based on intraoperative findings were 37.3% and 92.7%; the PPV and NPV were 63.4% and 81.4%, respectively. Sensitivity and specificity of ultrasound for detecting an appendicolith based on pathology were 58.1% and 78.3%; the PPV and NPV were 33.1% and 91.0%, respectively. Results were similar when equivocal ultrasound and negative appendectomies were excluded.

CONCLUSIONS

The high specificity and NPV suggest that ultrasound is a reliable test to exclude CA and an appendicolith in patients being considered for nonoperative management of simple appendicitis.

Timing of antimicrobial prophylaxis and infectious complications in pediatric patients undergoing appendectomy

PURPOSE

Antibiotic administration within one hour prior to incision is a common quality metric; however, antibiotics are typically started at the time of diagnosis in pediatric patients with acute appendicitis. The purpose was to determine if antibiotic administration within one hour prior to incision reduces the incidence of surgical site infections (SSI) in pediatric patients with acute appendicitis started on parenteral antibiotics upon diagnosis.

METHODS

A retrospective review was performed of 478 patients aged 0-18years who underwent appendectomy for acute appendicitis from 7/2013 to 4/2015. Patients were categorized based on timing of antibiotic administration; there were 198 patients in Group A (<60min before) and 280 in Group B (>60min before).

RESULTS

Demographics and operative time (A: 30.5±9.9 vs B: 30.8±12.2min, p=0.51) were similar. Procedures were performed laparoscopically and the groups had similar proportions of single-incision operations (A: 53% vs B: 55%, p=0.64). There was no difference in the incidence of superficial SSI (A: 2.0% vs B: 2.1%, p=1.0) or intraabdominal abscess (A: 4.0% vs B: 3.6%, p=0.81) and this remained true when stratified by intraoperative classification.

CONCLUSION

Antibiotic administration within one hour of appendectomy in pediatric patients with acute appendicitis who receive antibiotics at diagnosis did not change the incidence of postoperative infectious complications.

TYPE OF STUDY

Treatment study.

LEVEL OF EVIDENCE

III.

Risk stratification in pediatric perforated appendicitis: Prospective correlation with outcomes and resource utilization

PURPOSE

Despite a wide spectrum of severity, perforated appendicitis in children is typically considered a single entity in outcomes studies. We performed a prospective cohort study to define a risk stratification system that correlates with outcomes and resource utilization.

METHODS

A prospective study was conducted of all children operated for perforated appendicitis between May 2015 and December 2016 at a tertiary free-standing university children's hospital. Surgical findings were classified into one of four grades of perforation: I. localized or contained perforation, II. Contained abscess with no generalized peritonitis, III. Generalized peritonitis with no dominant abscess, IV. Generalized peritonitis with one or more dominant abscesses. All patients were treated on a clinical pathway that involved all points of care from admission to final follow-up. Outcomes and resource utilization measures were analyzed using Fisher's exact test, Kruskal-Wallis test, One-way ANOVA, and logistic regression.

RESULTS

During the study period, 122 patients completed treatment, and 100% had documented follow-up at a median of 25days after operation. Grades of perforation were: I, 20.5%; II, 37.7%; III, 10.7%; IV, 31.1%. Postoperative abscesses occurred in 12 (9.8%) of patients, almost exclusively in Grade IV perforations. Hospital stay, duration of antibiotics, TPN utilization, and the incidence of postoperative imaging significantly increased with increasing grade of perforation.

CONCLUSION

Outcomes and resource utilization strongly correlate with increasing grade of perforated appendicitis. Postoperative abscesses, additional imaging, and additional invasive procedures occur disproportionately in patients who present with diffuse peritonitis and abscess formation. The current stratification allows risk-adjusted outcome reporting and appropriate assignment of resource burden.

LEVEL OF EVIDENCE

I (Prognosis Study).

Standardization of care for pediatric perforated appendicitis improves outcomes

BACKGROUND

The treatment of perforated appendicitis in children is characterized by significant variability in care, morbidity, resource utilization, and outcomes. We prospectively studied how minimization of care variability affects outcomes.

METHODS

A clinical pathway for perforated appendicitis, in use for three decades, was further standardized in May 2015 by initiation of a disease severity classification, refinement of discharge criteria, standardization of the operation, and establishment of criteria for use of postoperative total parenteral nutrition, imaging, and invasive procedures. Prospective evaluation of all children treated for 20months on the new fully standardized protocol was conducted and compared to a retrospective cohort treated over 58months prior to standardization. Differences between outcomes before and after standardization were analyzed using regression analysis techniques to adjust for disease severity.

RESULTS

Median follow-up time post discharge was 25 and 14days in the post- and prestandardization groups, respectively. Standardization significantly reduced postoperative abscess (9.8% vs. 17.4%, p=0.001) and hospital stay (p=0.002). Standardization reduced the odds of developing a postoperative abscess by four fold.

CONCLUSION

Minimizing variability of care at all points in the treatment of perforated appendicitis significantly improves outcomes.

TYPE OF STUDY

Prospective Cohort Study.

LEVEL OF EVIDENCE

Level II.

Predictors of a histopathologic diagnosis of complicated appendicitis

BACKGROUND

Despite its utilization, the intraoperative (IO) assessment of complicated appendicitis (CA) is subjective. The histopathologic (HP) diagnosis should be the gold standard in identifying patients with CA; however, it is not immediately available to guide postoperative management. The objective of this study was to identify predictors of an HP diagnosis of CA.

MATERIALS AND METHODS

A retrospective review of all patients who underwent appendectomy at our institution from 2011-2013 was conducted. CA was defined by perforation or abscess on pathology report. Predictors of an HP diagnosis of CA were evaluated using a multivariable regression model.

RESULTS

A total of 239 of 1066 patients had CA based on IO assessment, whereas 143 of 239 patients (60%) had CA on HP and IO assessment. On multivariable analysis, an IO diagnosis of CA was associated with an HP diagnosis of CA (odds ratio [OR]: 10.92; 95% confidence interval [CI]: 7.19-16.58). Other risk factors were age (OR: 1.28; 95% CI: 1.09-1.49), number of days of pain (OR: 1.20; 95% CI: 1.07-1.37), increased heart rate (OR: 1.14; 95% CI: 1.02-1.26), appendix size (OR: 1.09; 95% CI: 1.03-1.16), and an appendicolith (OR: 1.74; 95% CI: 1.12-2.71) on preoperative CT imaging.

CONCLUSIONS

In addition to age, increased heart rate, pain duration, appendix size and appendicolith, the IO assessment is also associated with an HP diagnosis of CA; however, 40% of patients were incorrectly classified. Using these predictors with improved IO grading may achieve more accurate diagnosis of CA.

A call for a standardized definition of perforated appendicitis

BACKGROUND

Abscess rates have been reported to be as low as 1% and as high as 50% following perforated appendicitis (PA). This range may be because of lack of universal definition for PA. An evidence-based definition (EBD) is crucial for accurate wound classification, risk-stratification, and subsequent process optimization. ACS NSQIP-Pediatric guidelines do not specify a definition of PA. We hypothesize that reported postoperative abscess rates underrepresent true incidence, as they may include low-risk cases in final calculations.

METHODS

Local institutional records of PA patients were reviewed to calculate the postoperative abscess rate. The ACS NSQIP-Pediatric participant use file (PUF) was used to determine cross-institutional postoperative abscess rates. A PubMed literature review was performed to identify trials reporting PA abscess rates, and definitions and rates were recorded.

RESULTS

20.9% of our patients with PA developed a postoperative abscess. The ACS NSQIP-Pediatric abscess rate was significantly lower (7.61%, p<0.001). In the eighteen published studies analyzed, average abscess rate (14.49%) was significantly higher than ACS NSQIP-Pediatric (p<0.001). There was significantly more variation in trials that do not employ an EBD of perforation (Levene's test F-value =6.980, p=0.018).

CONCLUSIONS

A standard EBD of perforation leads to lower variability in reported postoperative abscess rates following PA. Nonstandard definitions may be significantly altering the aggregate rate of postoperative abscess formation. We advocate for adoption of a standard definition by all institutions participating in ACS NSQIP-Pediatric data submission.

LEVEL OF EVIDENCE

III.

Evaluation of the microbiome in children's appendicitis

BACKGROUND/AIM

The role of the microbiome has been widely discussed in the etiology of appendicitis. The primary aim was to evaluate the microbiome in the normal appendix and in appendicitis specifically divided into the three clinically and histopathologically defined grades of inflammation. Secondary aims were to examine whether there were any microbiome differences between proximal and distal appendices, and relate the microbiome with histopathological findings.

METHODS

A prospective pilot study was conducted of children undergoing appendectomy for appendicitis. The diagnosis was based on histopathological analysis. Children with incidental appendectomy were used as controls. The proximal and distal mucosa from the appendices were analyzed with 16S rRNA gene sequencing.

RESULTS

A total of 22 children, 3 controls and 19 appendicitis patients; 11 phlegmonous, 4 gangrenous, and 4 perforated appendices, were prospectively included. The amount of Fusobacterium increased and Bacteroides decreased in phlegmonous and perforated appendicitis compared to controls, but statistical significance was not reached, and this pattern was not seen in gangrenous appendicitis. No relation could be seen between different bacteria and the grade of inflammation, and there was a wide variation of abundances at phylum, genus, and species level within every specific group of patients. Further, no significant differences could be detected when comparing the microbiome in proximal and distal mucosa, which may be because the study was underpowered. A trend with more abundance of Fusobacteria in the distal mucosa was seen in appendicitis patients with obstruction (25 and 13 %, respectively, p = 0.06).

CONCLUSION

The pattern of microbiome differed not only between groups, but also within groups. However, no statistically significant differences could be found in the microbiome between groups or clinical conditions. No correlation between a specific bacteria and grade of inflammation was found. In the vast majority of cases of appendicitis, changes in microbiome do not seem to be the primary event. Since there seem to be differences in microbiome patterns depending on the sample site, the exact localization of biopsy sampling must be described in future studies.

Urinary biomarkers in pediatric appendicitis

PURPOSE

The diagnosis of pediatric appendicitis is still a challenge, resulting in perforation and negative appendectomies. The aim of this study was to evaluate novel biomarkers in urine and to use the most promising biomarkers in conjunction with the Pediatric Appendicitis Score (PAS), to see whether this could improve the accuracy of diagnosing appendicitis.

METHODS

A prospective study of children with suspected appendicitis was conducted with assessment of PAS, routine blood tests, and measurements of four novel urinary biomarkers: leucine-rich α-2-glycoprotein (LRG), calprotectin, interleukin 6 (IL-6), and substance P. The biomarkers were blindly determined with commercial ELISAs. Urine creatinine was used to adjust for dehydration. The diagnosis of appendicitis was based on histopathological analysis.

RESULTS

Forty-four children with suspected appendicitis were included, of which twenty-two (50 %) had confirmed appendicitis. LRG in urine was elevated in children with appendicitis compared to children without (p < 0.001), and was higher in children with gangrenous and perforated appendicitis compared to those with phlegmonous appendicitis (p = 0.003). No statistical significances between groups were found for calprotectin, IL-6 or substance P. LRG had a receiver operating characteristic area under the curve of 0.86 (95 % CI 0.79-0.99), and a better diagnostic performance than all routine blood tests. LRG in conjunction with PAS showed 95 % sensitivity, 90 % specificity, 91 % positive predictive value, and 95 % negative predictive value.

CONCLUSION

LRG, adjusted for dehydration, is a promising novel urinary biomarker for appendicitis in children. LRG in combination with PAS has a high diagnostic performance.

Paradigm Shifts in the Treatment of Appendicitis

Acute appendicitis is the most common cause of emergent surgery in children. Historically, surgical dogma dictated emergent appendectomy due to concern for impending perforation. Recently, however, there has been a paradigm shift in both the understanding of its pathophysiology as well as its treatment to more nonoperative management. No longer is it considered a spectrum from uncomplicated appendicitis inevitably progressing to complicated appendicitis over time. Rather, uncomplicated and complicated appendicitis are now considered two distinct pathophysiologic entities. This change requires not only educating the patients and their families but also the general practitioners who will be managing treatment expectations and caring for patients long term. In this article, we review the pathophysiology of appendicitis, including the differentiation between uncomplicated and complicated appendicitis, as well as the new treatment paradigms. [Pediatr Ann. 2016;45(7):e235-e240.].

Mean Platelet Volume and Platelet Distribution Width as Markers in the Diagnosis of Acute Gangrenous Appendicitis

Introduction. Acute gangrenous appendicitis (AGA) is a common medical condition; however, the grade of appendicitis usually cannot be established preoperatively. We have attempted to identify some indicators, such as the mean platelet volume (MPV) and the platelet distribution width (PDW), to diagnose AGA. Aims. To evaluate whether or not the MPV and PDW are suitable markers to diagnose AGA. Methods. A retrospective study of 160 patients with AGA and 160 healthy patients was undertaken. Disease diagnosis was confirmed based on the pathologic examination of surgical specimens. Patient white blood cell (WBC) count, neutrophil ratio (NR), platelet (PLT) count, MPV, PDW, and hematocrit (HCT) were analyzed. Receiver operating characteristic (ROC) curves were used to evaluate the sensitivity and specificity of these indices in AGA. Results. There were no significant differences between the AGA and control groups in age and gender. Compared to the control group, the WBC count, NR, and PDW were significantly higher (P < 0.001, resp.) and the MPV and HCT were significantly lower (P < 0.001, resp.) in the AGA group. The diagnostic specificities of the WBC count, NR, PLT count, MPV, PDW, and HCT were 86.3%, 92.5%, 58.1%, 81.7%, 83.9%, and 66.3%, respectively. Therefore, the NR had the highest diagnostic specificity for the diagnosis of AGA. Conclusions. This is the first study to assess the MPV and PDW in patients with AGA. Our present study showed that the MPV is reduced and the PDW is increased in patients with AGA; the sensitivity of PDW was superior to the MPV. A decreased MPV value and an increased PDW could serve as two markers to diagnose AGA. The NR had the highest specificity for the diagnosis of AGA.

Operative Findings Are a Better Predictor of Resource Utilization in Pediatric Appendicitis

PURPOSE

Post-operative management following appendectomy is dependent upon intraoperative assessment. We determined concordance between surgical and histopathologic diagnosis to better predict resource utilization in pediatric patients undergoing appendectomy.

METHODS

A retrospective analysis of 326 patients with operative appendicitis from July 2012 to July 2013 was performed. Based on operative findings, patients were classified as simple appendicitis (SA) or complex appendicitis (CA).

RESULTS

The SA group included 194 (59.5%) patients while the CA group included 132 (40.5%) patients. There were significant differences in WBC, CRP, operative time, length of stay, and 30-day complications. Seventy percent of patients with intra-operative findings of SA were found to have complex pathology while 10.6% with intra-operative findings of CA were found to have simple pathology. There is poor agreement between intra-operative findings and histopathologic findings (κ=0.173). Although 70% of patients with intra-operative findings of SA were labeled as complex pathology, 86% followed a fast track protocol (same day discharge) with a low complication rate (1.7%).

CONCLUSIONS

Pathology findings that overestimate the severity of disease correlate poorly with the post-operative outcomes for appendicitis. We conclude that operative findings are more predictive of clinical course than histopathologic results. This can have an impact on resource utilization planning.

Correlating surgical and pathological diagnoses in pediatric appendicitis

BACKGROUND

The stratification of appendicitis into simple and complex variants has far-reaching implications. While the operative diagnosis made by the surgeon dictates clinical management, the pathologic diagnosis often differs and is frequently used for coding and reimbursement. The purpose of this study was to examine discrepancies between the operative and pathologic diagnoses with subsequent correlation to clinical outcomes.

METHODS

Patients with acute appendicitis from July 2011 to July 2012 were identified. Diagnoses included simple (normal, acute, and suppurative) and complex (gangrenous and perforated). We evaluated the inter-rater reliability between pathologic and operative diagnoses in the five appendicitis categories. Clinical outcomes of deep and superficial surgical site infections were evaluated according to the pathologic and surgical diagnosis.

RESULTS

During the study period, we identified 1166 patients with acute appendicitis. The surgeon and pathologist agreed on the specific diagnosis (acute, suppurative, gangrenous, perforated, normal) in 48% of patients (kappa 0.289, 95% CI 0.259-0.324, p=0.001). Agreement on disease severity (simple vs. complex) improved to 82%. The operative diagnosis more accurately predicted infectious complications than the pathologic diagnoses.

CONCLUSION

Significant discordance exists between surgical and pathologic diagnoses. While the relevance of this discordance to clinical outcomes is still not clear, a potential for incorrect hospital coding and subsequent reimbursement exists. Future quality improvement projects should focus on standardizing the surgical and pathologic diagnoses.

Determinants of postoperative abscess occurrence and percutaneous drainage in children with perforated appendicitis

PURPOSE

Postoperative abscesses after perforated appendicitis have no clear risk factors or indications for percutaneous drainage. Our study addressed these two issues.

METHODS

A logistic regression model was used to delineate risk factors for postoperative abscess in children with perforated appendicitis treated during a recent 5-year period. Drainage of abscess was compared to antibiotic treatment.

RESULTS

Postoperative abscess occurred in 42 (14.8%) of 284 patients. Higher WBC count, presence of bowel obstruction at presentation, diffuse peritonitis with a dominant abscess at surgery, and one specific surgeon were significantly associated with postoperative abscess, while fever or pain requiring narcotics at the time of abscess diagnosis was significantly associated with drainage. Compared to non-drainage, those drained had longer hospital stay including readmissions (15.9 ± 5.3 vs. 12.2 ± 4.6 days, p < 0.005) and less readmissions (9.5 vs. 33.3%, p = 0.06). Over the 5-year period, there was no increased trend in abscess occurrence (p = 0.56), but there was an increased trend in the use of percutaneous drainage (p = 0.02).

CONCLUSIONS

The risk of a postoperative abscess can be predicted by specific clinical characteristics, surgical findings, and treatment-related factors. Percutaneous drainage was associated with longer hospital stays, but less readmissions.

Benefits of an abridged antibiotic protocol for treatment of gangrenous appendicitis

BACKGROUND

We previously reported a validated, objective definition of gangrenous, nonperforated appendicitis. In this study, we compared a cohort of children with gangrenous appendicitis treated with abridged antibiotics (AA) to another treated with prolonged antibiotics (PA).

METHODS

In 2012, our service changed its standard of care for gangrenous appendicitis from PA to AA. In PA, patients received postoperative triple antibiotics until ileus resolved, they were afebrile (<37.5°C) for 24hours, and achieved a normal WBC count. In AA, patients received two doses of postoperative triple antibiotics. A PA cohort during a 12-month period (February 2010-January 2011) was compared to an AA cohort during another 12-month period (April 2012-March 2013).

RESULTS

Twenty patients were treated with AA and 38 patients with PA. AA patients had a significantly shorter overall length of stay (2.1±1.58 vs. 3.18±1.09days, p=0.003), as well as a significantly shorter postoperative stay (1.85±1.42 vs. 2.95±1.14days, p=0.002). There were no differences between the AA and PA cohorts in wound infections (0%), intraabdominal infections (0%), or appendicitis-related readmissions (0%).

CONCLUSIONS

Abridged postoperative antibiotics for gangrenous appendicitis significantly shorten hospital stay without increasing complications.