Hyponatremia-A New Diagnostic Marker for Complicated Acute Appendicitis in Children: A Systematic Review and Meta-Analysis

The Role of Vascular Cell Adhesion Molecule-1 (VCAM-1) in Predicting Complicated Appendicitis in Children

BACKGROUND

Acute appendicitis is a common abdominal emergency observed in emergency departments (ED). Distinguishing between uncomplicated and complicated appendicitis is important in determining a treatment strategy. Serum soluble vascular cell adhesion molecule-1 (VCAM-1) is an inflammatory biomarker. We aimed to determine the role of VCAM-1 in predicting complicated appendicitis in children.

METHODS

Pediatric patients with suspected appendicitis admitted to the ED were enrolled in this prospective study. Pre-surgical serum VCAM-1 was tested in children with acute appendicitis within 72 h of symptoms (from day 1 to day 3). Serum VCAM-1 levels were further analyzed and compared between patients with and without complicated appendicitis.

RESULTS

Among the 226 pediatric appendicitis patients, 70 had uncomplicated appendicitis, 138 had complicated appendicitis, and 18 had normal appendices. The mean serum VCAM-1 levels in patients with perforated appendicitis were higher than in those with simple appendicitis (p < 0.001). On day 1 to day 3, the mean VCAM-1 levels in patients with complicated appendicitis were all significantly higher than in those with uncomplicated appendicitis (all p < 0.001).

CONCLUSION

Serum VCAM-1 levels may be helpful in differentiating uncomplicated and complicated appendicitis in children and could predict appendiceal perforation.

The Predictive Value of Plasma Sodium and Other Laboratory Parameters in Determining Complicating Appendicitis in Children

OBJECTIVE

Finding a reliable preoperative predictor of complicated acute appendicitis (AA) has been a challenging diagnostic problem. The present study aimed to identify potential factors that may predict complicated AA in the pediatric emergency department (ED) based on routine, widely available laboratory tests on admission to the ED, including plasma sodium concentration.

METHODS

We retrospectively reviewed clinical and laboratory data of pediatric patients with AA who underwent emergency surgery at our department between January 2020 and December 2022. The patients were divided into two groups: histopathologically proven complicated AA (n = 80), and non-complicated AA (n = 155).

RESULTS

Complicated AA was associated with reduced plasma sodium and chloride concentrations (p < 0.001, both), decreased values of lymphocytes (p = 0.002), elevated C-reactive protein (CRP) ( p < 0.001), elevated values of white blood cells (WBC) and neutrophils (p = 0.012 and 0.001, respectively). In binomial logistic regression, increased levels of CRP and WBC, and decreased levels of sodium were predictors of complicated AA. The area under the ROC curve was 0.825 (95% CI 0.764, 0.886).

CONCLUSION

We identified mild hyponatremia and elevated CRP and WBC values as potential markers for distinguishing complicated from uncomplicated pediatric AA with implications for surgical approaches for treating complicated AA and conservative approaches for treating uncomplicated AA.

Usefulness of serum sodium levels as a novel marker for predicting acute appendicitis severity: a retrospective cohort study

BACKGROUND

Early and accurate preoperative diagnosis of complicated appendicitis mandates the identification of new markers. The aim of this study is to determine whether preoperative serum sodium levels are useful for predicting the severity of acute appendicitis.

METHODS

We retrospectively analyzed 475 patients who underwent emergency appendectomies between January 2018 and February 2023 in a general hospital in Brazil. The patients were divided into 2 groups: complicated (n = 254) and uncomplicated (n = 221). Hyponatremia was defined as serum sodium levels < 136 mEq/L. The primary outcome was to evaluate if hyponatremia is associated with complicated appendicitis.

RESULTS

The patients had a median age of 22 years, and the median serum sodium level was 137 mEq/L in patients with complicated appendicitis and 139 mEq/L in uncomplicated appendicitis (P < 0.001). The analysis of the receiver operating characteristic curve used as the best cutoff value of serum sodium of 136 mEq/L with a sensitivity of 45.7%, specificity of 86.4%, positive predictive value of 79.5%, and negative predictive value of 58.1% for the diagnosis of complicated AA. Of the 254 patients with complicated appendicitis, 84 (33.1%) had serum sodium levels below 136 mEq/L, while only 12 (5.4%) patients with uncomplicated appendicitis had values ​​below this cutoff. Patients with hyponatremia were 5 times more likely to develop complicated appendicitis. (odds ratio: 5.35; 95% confidence interval: 3.39-8.45) CONCLUSIONS: Preoperative serum sodium levels are a useful tool for predicting the severity of acute appendicitis. Due to its low cost and wide availability, it has become an extremely relevant marker.

Utility of Ischemia-Modified Albumin as a Biomarker for Acute Appendicitis: A Systematic Review and Meta-Analysis

BACKGROUND

Acute appendicitis is a frequently encountered surgical emergency. Despite several scoring systems, the possibility of delayed diagnosis persists. In addition, a delayed diagnosis leads to an increased risk of complicated appendicitis. Hence, there is a need to identify biological markers to help clinicians rapidly and accurately diagnose and prognosticate acute appendicitis with a high sensitivity and specificity. Although several markers have been evaluated, the pressing concern is still the low specificity of these markers. One such marker is serum ischemia-modified albumin (IMA), which can be a novel biomarker for accurately diagnosing and prognosticating acute appendicitis.

METHODS

The authors conducted a systematic search of the PubMed, EMBASE, Web of Science, and Scopus databases through February 2023 as per the PRISMA guidelines. The difference in the levels of IMA between patients with acute appendicitis vs. healthy controls, and the difference in the levels of IMA between patients with complicated vs. non-complicated acute appendicitis were taken as the outcome measures. Statistical analysis was performed using a random effects model and mean difference (MD) was calculated. The methodological quality of the studies was assessed by utilizing the Newcastle-Ottawa scale.

RESULTS

A total of six prospective comparative studies were included in the meta-analysis. The analysis revealed that the mean level of serum IMA was significantly raised in the acute appendicitis group (MD 0.21, 95% CI 0.05 to 0.37, p = 0.01). Similarly, the mean serum IMA levels were also raised in the complicated appendicitis group compared to the non-complicated appendicitis group (MD 0.05, 95% CI 0.01 to 0.10, p = 0.02). Three of the studies included were, however, of poor methodological quality.

CONCLUSIONS

Serum IMA is a viable potential marker for diagnosing and prognosticating acute appendicitis. However, due to the limited methodological quality of available studies, further prospectively designed and adequately powered studies are needed.

Trends and Predictors of Pediatric Negative Appendectomy Rates: A Single-Centre Retrospective Study

BACKGROUND

Appendectomy is still the standard treatment for acute appendicitis in the majority of centers. Despite all available diagnostic tools, the rates of negative appendectomies are still relatively high. This study aimed to determine negative appendectomy rates and to analyze the demographic and clinical data of the patients whose histopathology report was negative.

METHODS

All patients younger than 18 years who underwent appendectomy for suspected acute appendicitis in the period from 1 January 2012 to 31 December 2021 were included in the single-center retrospective study. Electronic records and archives of histopathology reports were reviewed for patients with negative appendectomy. The primary outcome of this study was a negative appendectomy rate. Secondary outcomes comprehended the rate of appendectomies and the association of age, sex, body mass index (BMI), values of laboratory markers, scoring systems, and ultrasound reports with negative histopathology reports.

RESULTS

During the study period, a total of 1646 appendectomies for suspected acute appendicitis were performed. In 244 patients, negative appendectomy was reported regarding the patients' pathohistology. In 39 of 244 patients, other pathologies were found, of which ovarian pathology (torsion and cysts) torsion of greater omentum and Meckel's diverticulitis were the most frequent. Finally, the ten-year negative appendectomy rate was 12.4% (205/1646). The median age was 12 years (interquartile range, IQR 9, 15). A slight female predominance was noted (52.5%). A significantly higher incidence of negative appendectomies was noted in girls, with a peak incidence between the ages of 10 and 15 years (p < 0.0001). Male children whose appendectomy was negative had significantly higher BMI values compared to female patients (p = 0.0004). The median values of white blood cell count, neutrophil count, and CRP in the patients with negative appendectomy were 10.4 × 10⁹/L, 75.9%, and 11 mg/dL, respectively. The median of Alvarado's score was 6 (IQR 4; 7.5), while the median of the AIR score was 5 (IQR 4, 7). The rate of children with negative appendectomy who underwent ultrasound was 34.4% (84/244), among which 47 (55.95%) concluded negative reports. The rates of negative appendectomies were not homogenous in terms of distribution regarding the season. The incidence of negative appendectomies was more frequent during the cold period of the year (55.3% vs. 44.7%; p = 0.042).

CONCLUSIONS

The majority of negative appendectomies were performed in children older than 9 years and most frequently in female children aged 10 to 15 years. In addition, female children have significantly lower BMI values compared to male children with negative appendectomy. An increase in the utilization of auxiliary diagnostic methods such as computed tomography could affect the reduction in the pediatric negative appendectomy rate.

Diagnostic Accuracy of Leucine-Rich α-2-Glycoprotein 1 as a Non-Invasive Salivary Biomarker in Pediatric Appendicitis

The aim of this study is to evaluate the diagnostic accuracy of leucine-rich α-2-glycoprotein 1 (LRG1) in saliva as a novel biomarker for acute appendicitis in the pediatric population. From October 2021 to June 2022, 92 children aged 5 to 17 years who presented with acute abdomen and suspected acute appendicitis were enrolled in this prospective study. The parameters documented included demographic and clinical information, as well as operative and postoperative data. Patients were divided into two groups: those with acute appendicitis who underwent laparoscopic appendectomy (n = 46) and those without appendicitis (n = 46). The total white blood cell (WBC) count, percent of neutrophils, C-reactive protein (CRP) level, and salivary LRG1 were compared between groups. A commercially available enzyme-linked immunosorbent assay (ELISA) LRG kit was used to measure the LRG levels. The median salivary LRG1 level was significantly higher in the group of children with pathohistologically confirmed acute appendicitis compared to the control group: 233.45 ng/mL (IQR 114.9, 531.2) vs. 55.95 ng/mL (IQR 51.5, 117.9), p < 0.001. LRG1 had an overall good receiver-operator characteristic area under the curve of 0.85 (95% CI 0.76-0.92; p < 0.001). The optimal LRG1 cutoff with best separation between acute appendicitis and the controls was >352.6 ng/mL (95% CI from >270.7 to >352.6). Although the specificity was 100% at this cutoff, the sensitivity for identifying appendicitis was 36%. In addition, a significant difference was found between groups in the laboratory values of all inflammatory markers tested: WBC, absolute neutrophil count, and CRP (p < 0.001 for all). Although LRG1 in saliva showed a good AUC parameter and significantly higher values in patients with acute appendicitis compared to the controls, its usefulness in the patient population who present at emergency departments with abdominal pain is debatable. Future studies should focus on investigating its diagnostic potential.

Diagnostic Algorithm Based on Machine Learning to Predict Complicated Appendicitis in Children Using CT, Laboratory, and Clinical Features

To establish a diagnostic algorithm for predicting complicated appendicitis in children based on CT and clinical features.

METHODS

This retrospective study included 315 children (<18 years old) who were diagnosed with acute appendicitis and underwent appendectomy between January 2014 and December 2018. A decision tree algorithm was used to identify important features associated with the condition and to develop a diagnostic algorithm for predicting complicated appendicitis, including CT and clinical findings in the development cohort (n = 198). Complicated appendicitis was defined as gangrenous or perforated appendicitis. The diagnostic algorithm was validated using a temporal cohort (n = 117). The sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve (AUC) from the receiver operating characteristic curve analysis were calculated to evaluate the diagnostic performance of the algorithm.

RESULTS

All patients with periappendiceal abscesses, periappendiceal inflammatory masses, and free air on CT were diagnosed with complicated appendicitis. In addition, intraluminal air, transverse diameter of the appendix, and ascites were identified as important CT findings for predicting complicated appendicitis. C-reactive protein (CRP) level, white blood cell (WBC) count, erythrocyte sedimentation rate (ESR), and body temperature also showed important associations with complicated appendicitis. The AUC, sensitivity, and specificity of the diagnostic algorithm comprising features were 0.91 (95% CI, 0.86-0.95), 91.8% (84.5-96.4), and 90.0% (82.4-95.1) in the development cohort, and 0.7 (0.63-0.84), 85.9% (75.0-93.4), and 58.5% (44.1-71.9) in test cohort, respectively.

CONCLUSION

We propose a diagnostic algorithm based on a decision tree model using CT and clinical findings. This algorithm can be used to differentiate between complicated and noncomplicated appendicitis and to provide an appropriate treatment plan for children with acute appendicitis.

A Bizarre Cause of Acute Appendicitis in a Pediatric Patient: An Ingested Tooth

(1) Background: Among all possible causes, foreign bodies are the rarest cause of appendicitis in the pediatric population. In the majority of cases, ingested foreign bodies pass through the gastrointestinal tract without causing symptoms. However, those foreign bodies that pass through the lumen of the vermiform appendix cannot re-enter the colon and may cause acute appendicitis. So far, various foreign bodies have been described to enter the appendix and cause acute appendicitis, such as seeds, needles, toothpicks, plant material, or even hair. Tooth or dental implants as a cause of acute appendicitis have been described in only a few cases. To our knowledge, this is the first described case of the tooth causing acute appendicitis in the pediatric population. (2) Case presentation: A 14-year-old male patient presented to the emergency department complaining of pain in the right lower quadrant of the abdomen and vomiting that persisted for approximately 24 h. Until then, the patient was healthy and had no concomitant diseases. Physical examination revealed guarding and tenderness in the right lower abdominal quadrant. The white blood cell count was 17.1 × 10⁹/L with a neutrophil count of 91.1% and a C-reactive protein of 39.3 mg/dL. Ultrasonography of the abdomen revealed a thickened, inflamed appendix with a diameter of 11 mm and free periappendicular fluid. A 9 × 6 mm foreign body at the base of the appendix was visualized. The patient was diagnosed with acute appendicitis, and an emergency laparoscopic appendectomy was performed on the same day. Intraoperatively, gangrenous appendicitis was noted and removed without complications. Upon examination of the removed specimen, it was determined that the patient's appendicitis had been caused by an ingested tooth. As it later turned out, the patient had broken a lateral incisor while playing sports the day before admission without knowing that he had swallowed it. The patient recovered well and was discharged the day after surgery. (3) Conclusion: Although an extremely rare event, acute appendicitis can be caused by a swallowed tooth. This case highlights the importance of a thorough history in pediatric patients who present to the emergency department with suspected acute appendicitis to determine if there is a precipitating event that may have caused acute appendicitis.

Discriminatory capacity of serum total bilirubin between complicated and uncomplicated acute appendicitis in children: a systematic review and a diagnostic test accuracy meta-analysis

This study aimed to examine the ability of serum total bilirubin (STB) to discriminate between complicated and uncomplicated paediatric acute appendicitis (PAA). We conducted a systematic review of the literature that involved an extensive search in the main databases of medical bibliography (Medline, PubMed, Web of Science, OVID, Scopus, Cochrane Library). Two independent reviewers selected the relevant articles based on the previously defined inclusion and exclusion criteria. Methodological quality of the selected articles was assessed using the QUADAS2 index. Data extraction was performed by two independent reviewers. A synthesis of the results, a standardization of the metrics and a random-effect meta-analysis were performed. Between-study heterogeneity was assessed in subgroup analysis by study design. In addition, a diagnostic test accuracy (DTA) meta-analysis was performed. This review included 8 studies with data from 3634 participants aged between 0 and 18 years (2230 with uncomplicated PAA and 1404 with complicated PAA). The random-effects meta-analysis showed significantly higher mean STB in the complicated PAA group than in the uncomplicated PAA group (difference = 0.27; 95% CI 0.06-0.48) and high heterogeneity (I² = 96%). In subgroup analyses by study design, the difference remained significant in prospective studies. The DTA meta-analysis resulted in an AUC of 0.83 (95% CI 0.79-0.86) and pooled sensitivity and specificity of 68.53% (95% CI 48.35%-83.51%) and 81.12% (95% CI 67.76%-89.78%), respectively. Mean values of STB are higher in children with complicated than uncomplicated acute appendicitis, and the diagnostic yield of STB seems to be high. Due to the high heterogeneity between studies, these results must be interpreted with caution.

Alterations and diagnostic performance of capillary ketonemia in pediatric acute appendicitis: a pilot study

INTRODUCTION

The diagnostic performance of capillary ketonemia (CK) has been previously evaluated in context of pediatric acute gastroenteritis. To our knowledge, there is no literature on its performance in the setting of pediatric acute appendicitis (PAA).

MATERIALS AND METHODS

In this study, 151 patients were prospectively included and divided into two groups: (1) patients with non-surgical abdominal pain in whom the diagnosis of PAA was excluded (n = 53) and (2) patients with a confirmed diagnosis of PAA (n = 98). In 80 patients (Group 1, n = 23 and group 2, n = 57) a CK was measured at the time of diagnosis. The PAA group was further classified into complicated (n = 18) and uncomplicated PAA (n = 39). Quantitative variables were compared between groups using the Mann-Whitney U test. Diagnostic performance of CK was evaluated with ROC curves.

RESULTS

CK values were 0.3 [0.1-0.9] mmol/L in group 1 and 0.7 [0.4-1.4] mmol/L in group 2 (p = 0.01). Regarding the type of PAA, CK values were 0.6 [0.4-0.9] mmol/L in uncomplicated PAA and 1.2 [0.8-1.4] mmol/L in complicated PAA (p = 0.02). The AUC for the discrimination between groups 1 and 2 was 0.68 (95% IC 0.53-0.82) (p = 0.24) and the AUC for the discrimination between uncomplicated PAA and complicated PAA was 0.69 (95% IC 0.54-0.85) (p = 0.04). The best cut-off point (group 1 vs group 2) resulted in 0.4 mmol/L, with a sensitivity of 80.7% and a specificity of 52.2%. The best cut-off point (non-complicated vs complicated PAA) resulted in 1.1 mmol/L, with a sensitivity of 61.1% and a specificity of 76.9%.

CONCLUSIONS

This study found significantly higher levels of CK in patients with PAA than in those with NSAP. Similarly, significantly higher levels were observed in patients with complicated than in those with uncomplicated PAA. Nevertheless, the diagnostic performance of CK was only moderate in the two settings analyzed. The potential usefulness of CK determination as a tool to guide the preoperative rehydration regimen of patients with PAA to prevent postoperative hyporexia and vomiting is a promising line of research and should be evaluated in future studies.