2024 Clinical Practice Guideline Update by the Infectious Diseases Society of America on Complicated Intra-abdominal Infections: Risk Assessment, Diagnostic Imaging, and Microbiological Evaluation in Adults, Children, and Pregnant People.

As the first part of an update to the clinical practice guideline on the diagnosis and management of complicated intra-abdominal infections in adults, children, and pregnant people, developed by the Infectious Diseases Society of America, the panel presents twenty-one updated recommendations. These recommendations span risk assessment, diagnostic imaging, and microbiological evaluation. The panel's recommendations are based upon evidence derived from systematic literature reviews and adhere to a standardized methodology for rating the certainty of evidence and strength of recommendation according to the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) approach.

Acute Appendicitis in the Setting of Infectious Mononucleosis: A Case Report.

Infectious mononucleosis (IM) is a viral illness caused by the Epstein-Barr virus that typically manifests with pharyngitis, lymphadenopathy, and fatigue. In rare cases, IM can cause acute appendicitis. We present the case of an 18-year-old female who arrived at the emergency department with worsening abdominal pain and an ongoing cough. Initial imaging showed a questionably dilated appendix, and a follow-up examination revealed cervical lymphadenopathy. She later returned to the ED with severe abdominal pain, clinical signs of acute appendicitis, and a positive monospot test, which led to an appendectomy. This case illustrates the need for complete history taking and thorough physical examination in patients with acute appendicitis, as their condition may be due to an atypical underlying cause.

Radiological diagnosis of severe appendicitis in 4 months infant with possible microperforation: A rare case report.

Appendicitis is the most common cause of acute abdominal pain requiring surgical intervention; however, it is extremely rare in infants. Its diagnosis and treatment are challenging due to nonspecific clinical signs and symptoms. As a result, delayed or missed diagnosis is common in young children and is associated with an increased risk of perforation and peritonitis. We reported a case of a 4-month-old healthy male child. The patient presented with abdominal distention and fever. After ruling out other possible causes, he was diagnosed with acute appendicitis, which was confirmed by a CT scan. A gangrenous appendix, dilated bowel loops, and free fluid in the abdomen were discovered during surgery. An appendectomy was performed. The appendix in infants has an average length of 4.5 cm compared with 9.5 cm in adults. Infantile appendicitis is considered rare but cases have been documented also in neonates, misdiagnosis rates are high due to rarity in this age group in addition to nonspecific signs and symptoms, which led to a high perforation rate. Ultrasonography can diagnose appendicitis in children with a sensitivity and specificity of 90%-95% without subjecting the child to radiation. A physician should always keep the diagnosis of appendicitis in mind in the infant age group, even though it is rare, as a delay in diagnosis and treatment has been associated with an increased risk of complications including appendicular perforation and peritonitis.

Modified Graham patch repair for cecal perforation: A case report.

INTRODUCTION AND IMPORTANCE: Acute appendicitis is a common cause of acute abdomen worldwide. The complications associated with it can sometimes be unpredictable and pose a dilemma in the management of such complications. CASE PRESENTATION: A case of 18 year female with complaints of right iliac fossa pain and vomiting was diagnosed clinically as acute appendicitis and underwent emergency open appendectomy where a cecal perforation was encountered intra-operatively for which a Modified Graham's Patch Repair was done. CLINICAL DISCUSSION: Acute appendicitis can sometimes present with complications like perforation, among which cecal perforation is rare and difficult to diagnose in the initial setting. Perforated appendicitis or colon can increase morbidity and mortality significantly. High degree of suspicion and early surgical approach can lead to identification of rare complications, which can still pose a surgical dilemma on the approach of management. CONCLUSION: Cecal perforation in suspected acute appendicitis is a rarely encountered intra operative complication. Management approaches can range from less invasive suture with omental patch repair to more invasive right hemicolectomy.

Survival among 148 patients with an incidentally detected appendiceal tumours at surgery for acute appendicitis: a population-based cohort follow-up study.

PURPOSE: To investigate the long-term prognosis of appendiceal tumours incidentally detected at appendicectomy for suspicion of benign appendicitis. METHODS: A retrospective register-based single centre cohort study was carried out, using data from the local acute appendicectomy quality register of cases operated on at the Department of Surgery, South General Hospital, Stockholm, Sweden. The local colorectal cancer register was also used to identify appendix tumours. The study period was between January 2004 and January 2023. Survival was calculated according to the Kaplan-Meier method. RESULTS: A total of 11,888 patients were registered in the acute acute appendicectomy register, 54% males and 46% females, median age 32 (Q1 = 21, Q3 = 47) (with 33.7% were 41 years or older). From the appendicectomy and colorectal registers 148 (1.2% of the total cohort) appendiceal tumours were found; 60% in females and 40% in males, median age 56 (Q1 = 43, Q3 = 70) (with 78.4% being 41 years or older). Tumours found were: Low grade Appendiceal Mucinous Neoplasms (LAMN, N = 64); Neuroendocrine Tumours (NET N = 24); adenocarcinomas or other form of carcinomas (N = 57); and adenomas (N = 3). The overall 5-year survival in patients operated for LAMN was 96.8%, for NET 93.3% and for adenocarcinoma 69.7%. The overall 5-year survival for all tumour patients was 85.7%. For the younger patients (< 51 years) with LAMN and NET, almost all survived to the end of follow-up. Survival of patients in the carcinoma group was statistically significantly lower than for the LAMN and NET groups, especially in females 51 years or older. In the group of tumour patients undergoing surgery (n = 146), primary surgery was laparoscopic in 47% and open in 52%. Two patients did not undergo surgery due to widespread disease. In 64% of cases operation was acute, whereas it was delayed and/or planned in 34%. Most procedures were laparoscopic appendicectomy 36%, followed by open appendicectomy 30%, right-sided hemicolectomy 14.6% (open 11.6% and laparoscopic 3%, acute operation 5.5%), ileocaecal resection 5% (acute operation 3.4%), and staging laparoscopy 7%. In 38% of the operated patients the tumour was discovered incidentally at histopathology examination. Two patients had CRS and HIPEC as the initial operation. Forthy-three per cent of the 146 tumour patients operated underwent a second procedure: CRS and HIPEC in 23.3% and right-sided hemicolectomy in 13.6% (laparoscopic 8.2% open 5.4%). CONCLUSION: Survival was high for patients with incidentally detected appendiceal LAMN or NET, but not so for carcinoma. Survival was lower in the carcinoma group older than 50 years, especially those sick and females.

Diagnostic value of systemic immune inflammation index in acute appendicitis and complicated appendicitis in pregnant patients.

INTRODUCTION: Acute pain in the right lower quadrant during pregnancy is difficult to approach and acute appendicitis must be excluded. The complication rate in pregnant acute appendicitis increases as a result of delayed diagnosis due to physiological and anatomic changes. The systemic immune inflammatory index (SII), which includes several inflammatory tests, is considered to be a good indicator of acute inflammation. The aim of the present study was to investigate the diagnostic value of SII in the diagnosis of acute appendicitis and complicated appendicitis in pregnant women. MATERIAL-METHOD: This was designed as a retrospective, single-center case-control study. This study was performed in pregnant women over 12 weeks of gestation who were diagnosed with acute appendicitis as indicated by pathology report and met the inclusion criteria. Vital parameters, demographic characteristics, laboratory values, presence of complicated appendicitis, and pathology reports were taken into analysis. RESULTS: The present study was performed with 76 pregnant women, including 38 pregnant women with acute appendicitis and 38 pregnant women with healthy controls. SII had a sensitivity of 82.0% and specificity of 66.7% with a cut-off value of 840.13 in pregnant acute appendicitis cases (AUC: 0.790; 95% CI: 0.686-0.984; p < 0.001) and SII level was significantly higher in complicated appendicitis cases with a sensitivity and specificity of 66.7% and 91.3%, respectively, with a cut-off value of 2301.66 (AUC: 0.812; 95% CI: 0.665-0.958; p = 0.001). CONCLUSION: SII is a cost-effective, rapid, easily calculated, and powerful marker that can be used for the diagnosis of both acute and complicated appendicitis in pregnant patients.

Evaluating the Diagnostic Accuracy of the Alvarado Score and Abdominal Ultrasound for Acute Appendicitis: A Retrospective Single-Center Study.

Background: Acute appendicitis is a complex diagnosis that often requires both clinical and radiological evaluation. Significant variations in diagnostic approaches are evident among clinicians and healthcare institutions. While certain guidelines advocate for risk stratification based on clinical characteristics, others emphasize the importance of pre-operative imaging. This study seeks to explore the accuracy of the Alvarado Score and abdominal ultrasound (AUS) in diagnosing acute appendicitis. Methods: Suspected cases of appendicitis admitted to Al-Thora Hospital in Ibb, Yemen, from Jan 2021 to July 2022 were evaluated. The demographics, clinical, and laboratory data were collected and analyzed. This study assessed Alvarado scores (calculated based on clinical evaluation and laboratory data) and pre-operative AUS findings, correlating them with post-operative and histopathology findings. The Alvarado scores and AUS sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) were assessed using the ROC curve. Results: Out of 1021 cases of acute abdomen, 171 patients were suspected of appendicitis. Using AUS along with the Alvarado score, appendicitis was presumed in 137 patients who underwent appendectomy. 130 (94.9%) patients had positive intraoperative and histopathology findings while 7 (5.1%) had negative findings. The Alvarado Score had a sensitivity and specificity of 94.62% and 87.80% at cutoffs of 6, respectively [Area under the curve (AUC): 0.985; 95% confidence interval (CI), 0.954 to 0.998; p < 0.0001]. Abdominal US showed a sensitivity of 98.46% and specificity of 82.93% (AUC:0.907; 95% CI, 0.853 to 0.946; p < 0.0001). Conclusion: Alvarado's score and AUS exhibited high sensitivity and specificity in diagnosing acute appendicitis. The substantial accuracy and efficacy of both the Alvarado score and AUS support their utilization as primary investigative tools in resource-limited settings. This approach can help avoid unnecessary appendectomies and minimize the financial burden on patients.

Acute appendicitis poses a diagnostic challenge, with a high rate of false-positive cases identified post-operatively. Computed tomography has been recommended by several surgical societies; however, it is limited by unaffordability and unavailability. Herein, we utilized the Alvarado score along with abdominal ultrasound as an alternative accurate, and cost-effective diagnostic approach. In this study, the negative appendectomy rate was 5.1%. The sensitivity of abdominal ultrasound in detecting appendicitis was 98.5%, with a specificity of 82.9%. The positive predictive value, negative predictive value, and accuracy were determined to be 94.8%, 94.4%, and 94.7%, respectively. The mean Alvarado score was 6.9±2.4, with a sensitivity and specificity of 97.81% and 97.06% at cutoffs of 6, respectively. The area under the curve values of the ROC curve for Alvarado's and abdominal ultrasound were 0.985 (95% CI, 0.954 to 0.998) and (AUC:0.907; 95% CI, 0.853 to 0.946), which was statistically significant (p < 0.0001).

A case of death after the severing three appendiceal arteries during appendectomy.

INTRODUCTION: Acute appendicitis is one of the most common acute abdominal issues requiring surgery and is usually treated by appendectomy. During the process of removing the appendix, the appendiceal artery is severed. In most individuals, the appendix is supplied by only one appendiceal artery. CASE PRESENTATION: A 50-year-old man underwent appendectomy. During the surgical procedure, the appendix artery and two accessory arteries of the appendix were severed, leading to massive hemorrhaging in the abdominal cavity, which ultimately resulted in the patient's unfortunate demise. CONCLUSION: Through this case, we hope that surgeons can learn more about the anatomy of the appendiceal artery and understand the possibility of accessory arteries to the appendix. During surgery, the blood vessels supplying the appendix should be carefully explored, and the "one-size-fits-all approach" should be avoided. Moreover, attention should be given to complications after appendectomy, and timely symptomatic treatment should be provided. Key points 1. Rare typing: The case of death due to improper handling of the accessory appendicular artery during appendectomy in patients with three appendiceal arteries is currently unreported. 2. Detailed anatomical knowledge: Surgeons performing an appendectomy need to make a detailed exploration of the blood vessel supply of the appendix to avoid ignoring anatomically different blood vessels. 3. Avoid a one-size-fits-all approach: In the surgical process, a "one-size-fits-all" approach should be avoided, that is, the same surgical approach should not be used in all cases, but should be adjusted according to the anatomical characteristics of the individual. 4. Observation of postoperative bleeding: In the perioperative period, peritoneal drainage should be closely observed. If a large amount of bloody fluid is found, timely surgical treatment should be carried out. 5. Attention to complications: Surgeons should pay.

Hidden Appendicoliths and Their Impact on the Severity and Treatment of Acute Appendicitis.

Background/Objectives: In patients diagnosed with uncomplicated acute appendicitis (UAA), the absence of calcified deposits or stones, called appendicoliths, often leads to consideration of non-operative treatment (NOT), despite the notable treatment failure rate associated with this approach. Previous research has indirectly estimated the prevalence of appendicoliths to range between 15% and 38% retrospectively by CT scan, intraoperative palpation, and pathology report, thereby potentially missing certain concrements. Our hypothesis proposes that this reported prevalence significantly underestimates the occurrence of appendicoliths, which could explain the high failure rate of 29% of patients with appendicitis observed with NOT. Methods: In our prospective study, conducted with a cohort of 56 adult patients diagnosed with acute appendicitis (AA), we employed intraoperative extracorporeal incisions of the vermiform appendix, in addition to standard diagnostic methods. Results: Our findings revealed 50% more appendicoliths by intraoperative incision (n = 36, p < 0.001) compared to preoperative imaging (n = 24). Appendicoliths were present in 71.4% (n = 40, p < 0.001) of AA patients. Conclusions: These results suggest that conventional diagnostic procedures plausibly underestimate the actual prevalence of appendicoliths, potentially elucidating the frequent treatment failures observed in NOT approaches applied to patients with UAA.

Can Physicians Delay Appendectomy for One Night in Children With Acute Appendicitis?

Background: In pediatrics, appendicitis is the leading cause of emergency surgery. It was previously believed that postponing the surgery could lead to the appendix rupture. Children with this condition can be difficult to diagnose. The evidence regarding the necessity of an immediate appendectomy is a topic of debate. In this study, we evaluated the medical records of patients who were diagnosed with acute appendicitis to determine whether postponing appendectomy for one night is safe or not. Methods: This study involved 534 individuals diagnosed with acute appendicitis, who were separated into two groups: those who underwent an appendectomy immediately (within 8 hours) and those who had a delayed procedure (between 8-18 hours). We recorded and compared demographic data, symptoms, laboratory results, time of symptoms, hospitalization duration, surgery duration, overall time, length of stay after surgery, and any other complications that occurred between the two groups. Results: The rate of surgical site infection (SSI) did not differ significantly between the groups (2.8% vs 4.2%, P=0.74). Additionally, there was no significant difference in the risk of perforation between the time of surgery in our study (21.9% vs 19.8%, P>0.05). Conclusion: Our findings suggest that there is no increased risk of complications such as perforation when appendectomy is delayed for up to 18 hours.

Spondylodiscitis Following Perforated Acute Appendicitis: A Case Report.

Spondylodiscitis is a multifactorial disease of significant medical and socioeconomic importance, the treatment of which presents a challenge to clinicians and surgeons. Acute appendicitis is a common inflammatory disease in children, with postoperative complications occurring in up to 55% of cases. We present the case of a 15-year-old male with symptoms of severe back pain and fever two months following surgery for perforated appendicitis. The computed tomography (CT) revealed spondylodiscitis of T12-L1 spinal level. Discectomy and posterior pedicle-screw fixation were performed, followed by antibiotic treatment resulted in the resolution of preoperative symptoms. To the best of our knowledge, this is the third case of spondylodiscitis after perforated acute appendicitis in literature. Timely diagnosis and treatment in cases of spondylodiscitis are prerequisites for lowering the rate of permanent neurological deficits in these patients.

A Tale of Two "Citis": Appendicitis Versus Crohn's Appendicitis.

Appendicitis is one of the most common emergencies worldwide. One of the rare causes of acute appendicitis is Crohn's disease (CD). Management of appendicitis should not be decided in haste without a complete workup of the patient, including coexisting symptoms and past history. The appendix is essential for intestinal homeostasis, preventing the development of certain pathologies. It is important to correlate clinical and radiographic findings in diagnosing and managing Crohn's appendicitis. The mainstay of management of CD with appendicitis involves the use of systemic steroids.

Early Diagnosis of Acute Appendicitis in the Second Trimester of Pregnancy Based on Non-typical Clinical Findings: Report of a Rare Case and a Mini-Review of the Literature.

Acute appendicitis is the most common non-obstetric reason for exploratory laparotomy during pregnancy. This case report involves a primigravida patient who presented to the emergency department of the General Hospital of Trikala at 15 weeks of gestation due to diffuse abdominal pain, primarily in the epigastric region. She also reported watery bowel movements. The ongoing atypical clinical symptoms, along with elevated inflammatory markers, strongly indicated a diagnosis of acute appendicitis. An immediate exploratory laparotomy was performed, during which acute localized inflammation of the appendix was found, leading to an appendectomy. Histological examination confirmed the diagnosis of acute appendicitis. The patient reported pain relief immediately after the surgery. On the fourth postoperative day, she was discharged without any signs of a threatened second-trimester miscarriage. At 39 gestational weeks, she delivered by elective cesarean section due to breech presentation. This paper discusses the case and highlights the significant challenges in the early diagnosis and management of acute appendicitis during pregnancy, emphasizing the importance of preventing potentially life-threatening complications for both the mother and the fetus.

How can the surgeon choose preoperatively the most appropriate antibiotic prophylaxis vs therapy in pediatric acute appendicitis?

INTRODUCTION: The aim of this study was to find statistically valid criteria to preoperatively divide acute appendicitis into simple and complicated to enable surgeons to administer the most appropriate antibiotic prophylaxis/therapy before surgery. MATERIALS AND METHODS: We retrospectively reviewed a cohort of patients who underwent appendectomy from January 2022 to December 2023. Patients included were 0-14 years of age. Exclusion criteria included patients who underwent interval appendectomy or concurrent procedures at the same time of appendectomy. We divided patients into two groups: simple (group S) and complicated (group C) appendicitis according to intraoperative finding. Generalized linear model (GLM) with logit function was developed to identify the predictive variables of the type of appendicitis (S vs C) in terms of CRP value, neutrophils percentage and WBC count adjusted for age and sex of patients. Finally, principal component analysis (PCA) was carried out to identify the cutoff value of statistically significant variables found in the previous analysis. RESULTS: One hundred and twenty patients were eligible (N female = 49, N male = 71) for the study. 74 and 46 patients were included in groups S and C, respectively. In a preliminary analysis using univariate and multivariate GLM, only CRP (p value = < 0.001) and neutrophils percentage (p value = 0.02) were predictive variables for the type of appendicitis. The GLM shows a statistical lower value of CRP (adjusted odds ratio [OR] per unit, 0.17 [95% CI, 0.08-0.39]) and neutrophil percentage (adjusted OR per unit, 0.37 [95% CI, 0.16-0.86]) in the S group compared to C adjusted to age and sex. PCA analysis revealed a P-ROC cutoff of 4.2 mg/dl and 80.1 of CRP value (AUC = 84%) and neutrophil percentage (AUC = 70%), respectively. CONCLUSIONS: We will perform a prospective study giving preoperative prophylactic cefazolin to patients with a CRP value under 4.2 mg/dl and amoxicillin-clavulanate therapy to patient with CRP value over 4.2 mg/dl.

Exceptional association of two species of bacteria causing acute appendicitis: Haemophilus influenzae and Enterobacter cloacae.

Appendicitis, typically caused by appendiceal lumen obstruction, is a prevalent abdominal surgical emergency worldwide. While most cases involve Enterobacterales, Haemophilus influenzae, primarily known for upper respiratory infections, is infrequently associated with gastrointestinal infections. This article presents an exceptional case of acute appendicitis caused by both Haemophilus influenza and Enterobacter cloacae in a 15-year-old child, highlighting the significance of recognizing uncommon pathogens in appendicitis and emphasizing the necessity for thorough microbiological investigations to refine diagnostic approaches.

Metastatic Breast Cancer Presenting as Acute Appendicitis: A Case Report and Literature Review.

Breast cancer is considered one of the most common cancers worldwide. The most common sites for breast cancer to metastasize are the lymph nodes, bones, lungs, brain, and liver. Involvement of the gastrointestinal tract is uncommon, and metastasis to the appendix is rare. We report a case involving a 43-year-old woman with no previous history of malignancy who presented with acute appendicitis and underwent laparoscopic appendectomy, with the final histopathological assessment revealing metastatic breast cancer.

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.

Introducing the ratio of cross diameters of the appendix for ultrasound diagnosis of acute appendicitis can significantly increase specificity.

PURPOSE: To validate whether the introduction of the ratio of the cross diameters on the transverse section of the appendix (RATIO) ≤ 1.18 is useful for improving the ultrasound diagnosis of acute appendicitis (AA). METHODS: Data from 220 patients with AA and 110 patients with a normal appendix were retrospectively studied. The RATIO ≤ 1.18, maximal outer diameter (MOD) > 6 mm, and a combination of RATIO ≤ 1.18 and MOD > 6 mm were used for predicting AA. The area under the receiver operating characteristic curve (AUC), sensitivity, specificity, positive and negative predictive values (PPV and NPV) were calculated. RESULTS: The RATIO ≤ 1.18, MOD > 6 mm, and a combination of RATIO ≤ 1.18 and MOD > 6 mm for predicting AA showed a sensitivity of 90, 100, and 90%; specificity of 79.1, 27.3, and 88.2%; and AUC of 0.845, 0.636, and 0.891, respectively. When comparing the outcomes between MOD > 6 mm and a combination of MOD > 6 mm and RATIO ≤ 1.18, the specificity and PPV increased from 27.3 to 88.2% and 73.3 to 93.8%, respectively (all P < 0.0001). The sensitivity and NPV decreased from 100 to 90% and 100 to 81.5%, respectively (all P < 0.0001). The AUC increased from 0.636 to 0.891 (P < 0.0001). When comparing the AUC of MOD > 6 mm, and a combination of RATIO ≤ 1.18 and MOD > 6 mm for predicting AA with the AUC in a previous study, there were no significant differences between each other (all P > 0.05). CONCLUSION: Introducing the RATIO ≤ 1.18 for the evaluation of AA can improve the diagnostic performance and significantly increase specificity.

Factors associated with early inhospital adverse outcome following surgery for acute appendicitis in Uganda: a multicenter cohort.

INTRODUCTION: Surgery for acute appendicitis has been associated with significant morbidity. This study aimed to determine the factors associated with early inhospital adverse outcomes following surgery for acute appendicitis in Uganda. METHODS: This was a multicentre, prospective cohort in which early inhospital outcome following surgery for acute appendicitis was assessed at 4 regional referral hospitals in Uganda. The occurrence of complications during the admission period was documented as well as the length of hospital stay. Factors associated with adverse outcomes were determined using Poisson regression. RESULTS: Of the 102 patients who underwent surgery for acute appendicitis, the majority were males 79(77.5%) with a mean age of 23.8(SD = 12.5) years. The perforated appendix was seen in 26 (25.5%) patients. Post-operative complications occurred in 21(20.6%) with the commonest being surgical site infection in 19(18.6%) patients. The median length of hospital stay was 3(IQR = 3-4) days with 43(42.2%) staying in hospital for more than 3 days. The presence of anemia (Hb < 8) (aRR = 1.376, CI = 1.159-1.634, P = < 0.001) and having a perforated appendix (aRR = 1.263, CI = 1.026-1.555, P = 0.027) were independently associated with occurrence of complications while being HIV positive (aRR = 1.379, CI = 1.105-1.721, P = 0.005) and having a perforated appendix (aRR = 1.258, CI = 1.019-1.554, P = 0.033) were independently associated with prolonged hospital stay. CONCLUSION: Community education about early presentation is still required in order to reduce the number of patients that present late which should, in turn, reduce the risk of complications and length of hospital stay.

Applying an explainable machine learning model might reduce the number of negative appendectomies in pediatric patients with a high probability of acute appendicitis.

The diagnosis of acute appendicitis and concurrent surgery referral is primarily based on clinical presentation, laboratory and radiological imaging. However, utilizing such an approach results in as much as 10-15% of negative appendectomies. Hence, in the present study, we aimed to develop a machine learning (ML) model designed to reduce the number of negative appendectomies in pediatric patients with a high clinical probability of acute appendicitis. The model was developed and validated on a registry of 551 pediatric patients with suspected acute appendicitis that underwent surgical treatment. Clinical, anthropometric, and laboratory features were included for model training and analysis. Three machine learning algorithms were tested (random forest, eXtreme Gradient Boosting, logistic regression) and model explainability was obtained. Random forest model provided the best predictions achieving mean specificity and sensitivity of 0.17 ± 0.01 and 0.997 ± 0.001 for detection of acute appendicitis, respectively. Furthermore, the model outperformed the appendicitis inflammatory response (AIR) score across most sensitivity-specificity combinations. Finally, the random forest model again provided the best predictions for discrimination between complicated appendicitis, and either uncomplicated acute appendicitis or no appendicitis at all, with a joint mean sensitivity of 0.994 ± 0.002 and specificity of 0.129 ± 0.009. In conclusion, the developed ML model might save as much as 17% of patients with a high clinical probability of acute appendicitis from unnecessary surgery, while missing the needed surgery in only 0.3% of cases. Additionally, it showed better diagnostic accuracy than the AIR score, as well as good accuracy in predicting complicated acute appendicitis over uncomplicated and negative cases bundled together. This may be useful in centers that advocate for the conservative treatment of uncomplicated appendicitis. Nevertheless, external validation is needed to support these findings.