Evaluation of Preoperative Clinical and Serological Determinations in Complicated Acute Appendicitis: A Score for Predicting Complicated Appendicitis

Usefulness of extended inflammatory parameters related to neutrophil activation reported by Sysmex XN-1000 hematology analyzer for predicting complicated acute appendicitis. Comparison with canonical inflammatory laboratory tests

AIM

Accurate diagnosis of complicated appendicitis is of importance to ensure that patients receive early and effective treatment, minimizing the risk of postoperative complications to promote successful recovery. Biochemical markers are a promising tool to identify complicated appendicitis. We aimed to evaluate the potential role of novel parameters related with neutrophil activation, known as "Extended Inflammation Parameters" (EIP), included in blood cell count reported by Sysmex XN-Series analyzers, compared to other canonical biomarkers in identifying complicated appendicitis.

METHOD

Prospective observational study including patients with confirmed diagnosis of acute appendicitis. C-reactive protein (CRP), procalcitonin, cell blood count, including white blood cell (WBC), absolute neutrophil (ANC) and immature granulocyte (IG) count and EIP (neutrophil reactivity [NEUT-RI] and granularity intensity [NEUT-GI]) were analyzed before surgery. Their accuracy to diagnose complicated appendicitis was tested in an ROC curve analysis.

RESULTS

Our population study included 119 patients, and appendicitis was complicated in 58 (48.7%). NLR, CRP and procalcitonin levels, ANC and IG count and NEUT-RI and NEUT-GI were higher in patients with complicated appendicitis. Regarding accuracy for complicated appendicitis, CRP was the biomarker with the highest performance (ROC AUC: 0.829), with an optimal cutoff of 73.1 mg/L (sensitivity: 63.8%, specificity: 88.5%). NEUT-RI and NEUT-GI achieved both significant but poor accuracy, with ROC AUC of 0.606 and 0.637, respectively.

CONCLUSIONS

Novel laboratory tests reported by Sysmex XN-Series analyzers have poor accuracy for identifying complicated appendicitis. In this study, CRP was the biomarker with the highest performance and may be useful as predictor of the severity of acute appendicitis.

Validation of scoring systems for the prediction of complicated appendicitis in adults using clinical and computed tomographic findings

OBJECTIVES

The study aimed to evaluate scoring systems for predicting complicated appendicitis in adults diagnosed with acute appendicitis on computed tomography.

METHODS

Three hundred twenty-five consecutive adult patients (mean age 51.9 ± 19.6 years, 212 women) diagnosed with acute appendicitis on computed tomography were retrospectively included. Clinical and imaging findings were compared between patients with and without complicated appendicitis, and independent associations were identified. As C-reactive protein was not available for most patients, 5 out of 8 scoring systems were modified. They, and a newly proposed system, were compared via area under the receiver operating characteristics (ROC) curve (AUC), Additionally, the latter was internally validated. Pairwise comparison was performed, and diagnostic performance of these scoring systems was obtained.

RESULTS

One hundred twenty-seven patients (36.8%) had complicated appendicitis. Significant independent associations were found between complicated appendicitis and duration of symptoms > 12 h, appendicolith, periappendiceal fat stranding, periappendiceal fluid, and extraluminal air (p values < 0.001 to 0.037; AUCs of 0.824-0.829). AUCs of 9 scoring systems ranged from 0.692 to 0.831. Of these, modified Atema, Kim HY, and proposed scores had similarly high and non-significantly different AUCs (0.793-0.831) on pairwise comparison. Their sensitivities, specificities, and accuracies were 73.0-90.6%, 48.5-70.6%, and 64.3-72.3%, respectively. Internal validity test demonstrated high AUCs (0.826-0.844) with one of the proposed scores using odds ratio having 100% sensitivity and 100% negative predictive value.

CONCLUSIONS

Few scoring systems, including proposed ones, had high AUCs, sensitivity, and reasonable specificities, which could potentially aid in safely selecting adult patients with acute appendicitis for nonoperative management.

CRITICAL RELEVANCE STATEMENT

The study suggests few scoring systems for predicting complicated appendicitis with high AUCs and reasonable sensitivities, potentially aiding in selecting patients for nonoperative management.

KEY POINTS

• The study evaluated existing and proposed new scoring systems to predict complicated appendicitis in adults with acute appendicitis on computed tomography. • Several factors were found to be significantly associated with complicated appendicitis, including duration of symptoms, appendicolith, periappendiceal fat stranding, periappendiceal fluid, and extraluminal air. • The modified Atema, Kim HY, and newly proposed scoring systems performed well, potentially aiding in nonoperative management selection.

Parsimonious clinical prediction model for the diagnosis of complicated appendicitis

Objective

To develop a logistic regression model that combines clinical and radiological parameters for prediction of complicated appendicitis.

Methods

248 patients with histologically proven uncomplicated (n = 214) and complicated (n = 34) acute appendicitis were analyzed retrospectively. All patients had undergone a presurgical abdominal and/or pelvic computed tomography (CT) scan, assessed by two radiologists. A model using univariate and multivariate logistic regression analyses was developed, and the strength of association between independent predictors and complicated acute appendicitis was evaluated by adjusted odds radio. Clinical parameters were gender, age, anorexia, vomiting, duration of symptoms, right lower abdominal quadrant (RLQ) tenderness, rebound tenderness, body temperature, white blood cell (WBC) count, and neutrophil ratio. Radiological parameters were appendix diameter, appendicolith, caecal wall thickening, mesenteric lymphadenopathy, extraluminal air, abscess, fat stranding, and periappendicular fluid.

Results

Four features (body temperature＞37.2 °C, vomiting, appendicolith, and periappendiceal fluid) were included in the logistic regression model, and yielded an area under the curve (AUC) of 0.87 (95% confidence interval (CI), 0.80-0.93), sensitive of 88%, and specificity of 74%.

Conclusion

The logistic regression model makes an accurate and simple prediction of complicated appendicitis possible.

Development of a scoring model based on objective factors to predict gangrenous/perforated appendicitis

BACKGROUND

The mortality rate of gangrenous/perforated appendicitis is higher than that of uncomplicated appendicitis. However, non-operative management of such patients is ineffective. This necessitates their careful exam at presentation to identify gangrenous/perforated appendicitis and aid surgical decision-making. Therefore, this study aimed to develop a new scoring model based on objective findings to predict gangrenous/perforated appendicitis in adults.

METHODS

We retrospectively analyzed 151 patients with acute appendicitis who underwent emergency surgery between January 2014 and June 2021. We performed univariate and multivariate analyses to identify independent objective predictors of gangrenous/perforated appendicitis, and a new scoring model was developed based on logistic regression coefficients for independent predictors. Receiver operating characteristic (ROC) curve analysis and the Hosmer-Lemeshow test were performed to assess the discrimination and calibration of the model. Finally, the scores were classified into three categories based on the probability of gangrenous/perforated appendicitis.

RESULTS

Among the 151 patients, 85 and 66 patients were diagnosed with gangrenous/perforated appendicitis and uncomplicated appendicitis, respectively. Using the multivariate analysis, C-reactive protein level, maximal outer diameter of the appendix, and presence of appendiceal fecalith were identified as independent predictors for developing gangrenous/perforated appendicitis. Our novel scoring model was developed based on three independent predictors and ranged from 0 to 3. The area under the ROC curve was 0.792 (95% confidence interval, 0.721-0.863), and the Hosmer-Lemeshow test showed a good calibration of the novel scoring model (P = 0.716). Three risk categories were classified: low, moderate, and high risk with probabilities of 30.9%, 63.8%, and 94.4%, respectively.

CONCLUSIONS

Our scoring model can objectively and reproducibly identify gangrenous/perforated appendicitis with good diagnostic accuracy and help in determining the degree of urgency and in making decisions about appendicitis management.

Prediction of peritoneal soiling in acute appendicitis with simple clinical and laboratory data. Prospective, multicenter, cohort study of 2,645 adult patients nationwide

BACKGROUND AND AIMS

In order to facilitate the preoperative prediction of complicated appendicitis, we propose a complementary approach by selecting an endpoint defined by the intraoperative finding of peritoneal soiling (PS).

METHODS

Over a 6-month period, 38 centers (5% of all public hospitals) attending emergency general surgery patients on a 24-hour, 7-days a week basis, enrolled consecutive adult patients requiring appendectomy. Patients were stratified according to the absence or the finding of PS during the surgical procedure.

RESULTS

A total of 2645 patients were included; median age (IQR) was 35 (22-51) years, 44.3% were female. The laparoscopic approach was used in 70.8% of appendectomies. In a third of patients (31.7%), there was PS with pus around the appendix, or bowel contents, free pus, or blood in the peritoneal cavity. To develop the prediction model, 1764 patients were randomly selected for the derivation cohort and the remaining 881 patients were assigned to the validation cohort. On multivariable logistic regression analysis of all patients, two clinical variables (age, and pulse) and three laboratory variables (serum urea, serum sodium, and white blood cell count) were individually associated (P < .05) with a greater probability of having PS (Hosmer-Lemeshow chi, 1.63; P = .99; C-statistic, 0.7). Based on the multivariable regression model, both static and dynamic nomograms were developed for the prediction of PS in patients with acute appendicitis.

CONCLUSIONS

The entry of simple clinical and laboratory variables in the dynamic nomogram may be useful in guiding the initial management of patients with acute appendicitis in resource-limited settings.