European Journal of Cardiovascular Medicine

Acute appendicitis is among the commonest surgical emergencies in children. A subset presents late with localized containment of infection, forming an appendicular mass (phlegmon) or appendiceal abscess, where inflamed appendix becomes walled off by omentum and adjacent bowel. These cases are clinically important because indiscriminate early surgery may increase the risk of bowel injury, unplanned ileocecal resection, and postoperative intra-abdominal collections, while prolonged conservative care may increase recurrence and readmission burden.¹–³

The traditional pediatric approach favored initial conservative management—bowel rest, intravenous antibiotics, and drainage of sizeable abscesses—followed by interval appendectomy weeks later.⁴,⁵ This was based on the concept that operating in an inflamed field increases technical difficulty, whereas delayed surgery allows safer dissection. However, interval appendectomy itself adds a second admission, anesthesia exposure, costs, and may be unnecessary because many children do not recur after successful conservative therapy.⁶,⁷ Histopathology studies of interval appendectomy specimens show residual inflammation in a substantial proportion, yet the clinical relevance is debated.⁸

In contrast, proponents of early operative management argue that definitive appendectomy during index admission avoids recurrence, avoids prolonged antibiotic courses, prevents missed alternative diagnoses, and improves compliance by eliminating the need for planned readmission.⁹,¹⁰ Modern laparoscopy has further encouraged early surgery in selected cases, but operative challenges persist, particularly in dense phlegmon or abscess with bowel adherence. Meta-analyses including mixed adult–pediatric data suggest that emergency surgery in appendicular abscess/phlegmon may carry increased operative time and higher likelihood of unplanned bowel resection compared with delayed/interval approaches.²

Recent evidence and guidelines increasingly support risk-stratified care: stable children with localized mass/abscess may benefit from non-operative therapy, while diffuse peritonitis, intestinal obstruction, sepsis, or failure to improve warrant surgery.¹,³ Imaging has become central in defining abscess size, appendicolith presence, and complications. Appendicolith, especially persistent appendicolith, has been linked with higher recurrence risk in some cohorts, supporting closer follow-up or selective interval appendectomy.¹¹,¹²

Despite growing literature, practice variation remains wide due to differences in imaging availability, interventional radiology support, antibiotic protocols, and surgical expertise.¹,³ Therefore, comparing conservative and operative strategies within a uniform institutional pathway is clinically useful. This study aims to evaluate outcomes of conservative versus operative management in children presenting with appendicular mass, focusing on treatment success, complications, hospital stay, readmissions, recurrence, and resource utilization.

A prospective observational comparative study was conducted in the Department of Pediatric Surgery at a tertiary care teaching hospital over a 24-month period. Operational definitions Appendicular mass was defined as a tender right iliac fossa inflammatory lump with supportive imaging (ultrasound/CT) showing phlegmon ± localized abscess without generalized peritonitis. Conservative success was defined as clinical improvement (afebrile, reduced pain/tenderness, improving appetite) with normalization/downtrend of inflammatory markers and no requirement for emergency surgery during index admission. Participants All eligible children presenting to emergency/pediatric surgery services were screened. Inclusion criteria • Age ≤18 years • Clinical suspicion of complicated appendicitis with palpable mass and/or imaging-confirmed phlegmon/abscess • Hemodynamically stable at presentation (for consideration of conservative arm) • Informed consent from parent/guardian (and assent where applicable) Exclusion criteria • Generalized peritonitis on examination • Septic shock or hemodynamic instability requiring immediate surgery • Intestinal perforation with diffuse contamination on imaging • Frank bowel obstruction requiring urgent exploration • Known inflammatory bowel disease, abdominal tuberculosis, malignancy • Prior appendectomy • Immunocompromised status (e.g., chemotherapy, high-dose steroids) if protocol required separate pathway Group allocation (institutional pathway) • Conservative group: IV broad-spectrum antibiotics (e.g., third-generation cephalosporin + metronidazole, adjusted by policy), bowel rest, analgesia, and serial clinical monitoring. Image-guided percutaneous drainage was considered for abscess ≥3 cm, persistent fever >48–72 hours, enlarging collection, or significant toxicity. Discharge followed sustained clinical improvement and tolerance of oral intake. Interval appendectomy was selective (recurrent symptoms, persistent appendicolith, parental preference, or surgeon discretion). • Operative group: Early appendectomy (laparoscopic/open) during index admission. Drain placement and peritoneal lavage were done as required. Postoperative antibiotics were given as per protocol. Outcomes Primary outcomes: treatment success, overall complications (wound infection, intra-abdominal abscess, bowel injury, ileus), length of hospital stay, readmission, and total cost (direct hospital charges). Secondary outcomes: recurrence after conservative success, need for interval appendectomy. Statistical analysis Categorical variables were compared using Chi-square/Fisher’s exact test. Continuous variables were analyzed using Student’s t-test or Mann–Whitney U test depending on distribution. Statistical significance was set at p<0.05.

Table 1. Baseline demographics

Interpretation: Both groups were comparable for age and sex. The conservative group had slightly longer symptom duration, consistent with delayed presentation and more organized inflammation.

Table 2. Clinical and laboratory profile

Interpretation: Inflammatory markers and symptom burden were similar, suggesting both arms included clinically comparable complicated appendicitis cases.

Table 3. Imaging characteristics

Interpretation: Abscess frequency tended to be higher in the operative group, though not statistically significant. Appendicolith distribution was similar, allowing comparison of recurrence risk drivers.

Table 4. Primary outcomes

Early operation achieved definitive treatment in all cases but conservative management still had a high success rate (~89%). Operative strategy showed slightly shorter index stay, though conservative failures contributed to longer stays.

Table 5. Complications

Wound infection was significantly higher after early surgery. Serious complications (bowel injury/unplanned resection) were uncommon but occurred only in operative cases, reflecting technical difficulty in dense mass.

Table 6. Follow-up outcomes and resource utilization

Conservative strategy required drainage in a minority and interval appendectomy in roughly one-third (selective policy). Recurrence occurred in ~13% of successfully treated cases, emphasizing the need for structured follow-up and selective surgery in high-risk children.

This comparative study demonstrates that initial conservative management of pediatric appendicular mass is successful in the majority of children and is associated with lower wound-related morbidity, while early operative management offers definitive therapy but with higher immediate complications. Our conservative success rate (~89%) aligns with contemporary pediatric evidence supporting non-operative therapy for appendiceal mass/abscess in clinically stable children.¹,³

A major concern in early surgery is operating in a hostile inflammatory field. Systematic reviews evaluating appendicular abscess/phlegmon suggest early surgery can increase operative time and the likelihood of unplanned bowel resection compared with delayed strategies.² Although such outcomes are rare in children, our findings of bowel injury/unplanned resection only in the operative arm support careful selection for early appendectomy. Pediatric meta-analysis specifically comparing early appendectomy to initial non-operative treatment for appendiceal mass/abscess found fewer overall complications with non-operative approaches, reinforcing that conservative care is often safer in this phenotype.¹

Wound infection was significantly more frequent after operative treatment in our cohort—an expected result due to contaminated dissection and drain use. Conservative care avoids wound complications but may increase resource utilization through prolonged IV antibiotics, drainage procedures, and repeat imaging. Evidence comparing antibiotics alone versus antibiotics plus percutaneous drainage suggests antibiotics can be effective initially, with drainage reserved for non-responders or sizable collections, optimizing cost-effectiveness.¹³ Our protocol similarly used drainage selectively.

Recurrence after successful conservative therapy remains the key reason many surgeons still favor routine interval appendectomy. Modern literature increasingly supports selective interval appendectomy rather than routine, because many children never recur and thus avoid unnecessary surgery.⁶,⁷ Histopathology following interval appendectomy often shows persistent inflammation, but this does not automatically mandate routine removal if clinical recurrence risk is low.⁸ Our recurrence rate (~13%) is comparable to pooled estimates from systematic reviews, where recurrence after non-operative management commonly ranges around 10–20%.⁶

Risk stratification is crucial. Presence of appendicolith, persistent symptoms, or inadequate clinical response may increase failure/recurrence, and recent pediatric studies emphasize tailoring the decision based on abscess size and symptom duration.⁴,¹¹ Additionally, guidelines emphasize operative management when generalized peritonitis, obstruction, or sepsis is present, while conservative management is appropriate for localized abscess/phlegmon in stable patients.³ This supports a pragmatic “conservative-first” approach with clear failure criteria and timely escalation.

Overall, our findings support a selective hybrid strategy: start conservatively in stable children, use image-guided drainage when indicated, and reserve early surgery for those with deterioration or non-response. This approach minimizes complications without compromising safety, while maintaining the ability to provide definitive treatment when required.

Conservative management of pediatric appendicular mass is highly effective and reduces wound-related morbidity and operative field complications. Early operative management provides definitive treatment but may carry higher immediate postoperative complications. A protocol-driven, risk-stratified approach—guided by clinical stability, imaging (abscess size), and response to antibiotics—appears optimal.

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