Comparison of outcomes of nonoperative management with versus without interval appendectomy for periappendiceal abscess in Korea: a retrospective cohort study
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Nonoperative management (NOM) with percutaneous drainage is widely used for periappendiceal abscesses, but the necessity of interval appendectomy (IA) remains debated. This study evaluated the feasibility of NOM without IA and compared outcomes with IA after NOM.
Methods
A retrospective review was conducted of 53 patients who underwent percutaneous drainage for periappendiceal abscess between January 2009 and December 2019 at Ewha Womans University Mokdong Hospital. Patients were categorized into NOM only (n=26) and IA after NOM (n=27). Clinical data, including demographics, abscess characteristics, laboratory findings, treatment course, and follow-up outcomes, were analyzed.
Results
The recurrence rate after NOM was 7.7%, with all recurrent cases successfully treated surgically and no malignancies detected. Patients in the NOM group were older (62.4±11.5 years vs. 49.5±21.9 years, P=0.007) and had more comorbidities (76.9% vs. 33.3%, P=0.004). The IA group had larger abscesses and higher inflammatory markers. NOM patients had shorter hospital stays (7.9±5.6 days vs. 12.9±6.6 days, P=0.003) and a shorter total antibiotic duration (median [interquartile range]: 15 days [12–18 days] vs. 21 days [15–27 days]; P=0.005). No drainage-related complications occurred.
Conclusion
NOM without IA appears to be a feasible option for selected patients with periappendiceal abscess. Larger prospective studies are warranted to validate these findings and refine patient selection.
Acute appendicitis is the most common cause of intra-abdominal infection requiring emergency surgical intervention. A subset of patients presents with complications such as periappendiceal abscess, often resulting from perforation, which poses unique management challenges.
Traditionally, appendectomy has been regarded as the definitive treatment for acute appendicitis, including its complicated forms [1,2]. However, in cases of periappendiceal abscess, immediate surgical intervention can carry substantial morbidity because of inflamed and friable tissues, frequently requiring more extensive procedures such as ileocecal resection or hemicolectomy [3–6]. Nonoperative management (NOM), consisting of antibiotics and percutaneous drainage, has gained broad acceptance as an initial approach for periappendiceal abscess [1,2,7,8]. Multiple studies have demonstrated its safety, effectiveness, and reduced complication rates compared with emergency surgery [9–12]. Moreover, NOM has been associated with shorter hospital stays and lower overall healthcare costs in carefully selected patients [13]. Despite these benefits, the necessity of interval appendectomy (IA) following successful NOM remains controversial [3,4,11,14]. The World Society of Emergency Surgery (WSES) guidelines also advocate a selective strategy, recommending IA only for patients at high risk of recurrence or with suspected underlying malignancy [7,8].
Objectives
This study aimed to evaluate the feasibility of NOM in patients with periappendiceal abscess and to compare outcomes between those managed with NOM alone and those undergoing NOM followed by IA. In addition, this study sought to determine whether IA is necessary in cases where symptoms resolve after NOM and to assess whether long-term follow-up strategies should be optimized to reduce the risk of missed malignancies.
METHODS
Ethics statement
This study was approved by the Institutional Review Board (IRB) of Severance Hospital in 2017 (No. 4-2017-1238). Because of the limited number of eligible patients, the IRB approval was extended in 2020 to allow continued data collection. For patients in the NOM group who discontinued outpatient follow-up, researchers contacted them by telephone to explain the study, obtain verbal consent, and collect information regarding recurrence and survival status. The process of obtaining verbal consent by telephone was explicitly reviewed and approved by the IRB. For patients in the IA group, informed consent was waived by the IRB because only medical records were analyzed. The study protocol strictly adhered to the ethical principles outlined in the Declaration of Helsinki for patient protection.
Study design and setting
This was a retrospective cohort study conducted at a tertiary referral center. The study included patients diagnosed with periappendiceal abscess who underwent percutaneous drainage (PCD) between January 2009 and December 2019. Patients were divided into two groups according to treatment strategy: NOM only and IA after NOM. Clinical data were collected from electronic medical records and included demographic characteristics, abscess size, laboratory results, treatment course, and follow-up outcomes. Follow-up data were obtained from outpatient visits and supplemented by telephone interviews when necessary.
Participants
A total of 85 patients with periappendiceal abscess were initially screened. After excluding 11 patients with alternative intra-abdominal diagnoses and 21 patients who underwent immediate appendectomy, 53 patients remained eligible and were included in the analysis (Fig. 1). All patients were initially managed with PCD performed under imaging guidance by interventional radiologists.
Patients were divided into two groups according to subsequent management strategy: NOM group (NOM only without IA; n=26) and IA group (IA after NOM; n=27). The NOM group consisted of patients who underwent PCD and achieved symptom resolution followed by catheter removal, without appendectomy during the index hospitalization. Patients in this group who later developed recurrence (defined as readmission with recurrent symptoms and imaging findings of appendicitis or periappendiceal abscess after catheter removal and initial recovery) remained classified under the NOM group. The IA group included patients who underwent appendectomy during the index hospitalization while the percutaneous catheter remained in place, or those who underwent surgery shortly after discharge during outpatient follow-up, as confirmed by medical records.
Appendectomy was selected as the initial treatment under the following circumstances: (1) abscess located at the tip or body of the appendix with an intact base and cecum; (2) small abscesses (≤2 cm); and (3) deep pelvic abscesses or those surrounded by adjacent bowel where PCD was technically challenging or unsafe. After drainage, subsequent treatment decisions were individualized. Patients with residual abscesses, persistent symptoms, or appendicoliths were managed with delayed appendectomy or resectional surgery. Catheter removal was determined based on clinical improvement, drainage output, and follow-up imaging. Patients discharged with indwelling catheters underwent outpatient removal once symptoms resolved and computed tomography (CT) confirmed abscess resolution. For patients opting for NOM, the risks of recurrence were explained, and follow-up CT scans were performed 3 to 4 weeks after drainage. Persistent abscesses or inflammation prompted surgical intervention, with or without colonoscopy. Patients with complete resolution were counseled regarding the risks and benefits of surgery versus continued NOM and were instructed to return if symptoms recurred.
Inclusion criteria were adults (≥18 years) diagnosed with periappendiceal abscess on CT who underwent initial PCD and had sufficient clinical data for analysis, including outpatient follow-up or structured telephone interviews. Exclusion criteria included incomplete or missing medical records, generalized peritonitis, sepsis, emergent conditions requiring immediate surgery, unresolved abscesses after drainage, suspected malignancy requiring urgent surgery, and pediatric patients (<18 years).
Variables
The primary outcome was the recurrence rate of appendicitis in patients managed with NOM without IA. Secondary outcomes included the feasibility and safety of NOM, evaluated by the need for subsequent surgical intervention, length of hospital stay, drainage duration, and total antibiotic use. Follow-up data were collected during outpatient visits and supplemented by structured telephone interviews to ensure completeness. Clinical outcomes were assessed using the following variables: duration of initial hospitalization, total hospitalization (including readmissions), drainage duration, and total antibiotic duration (including inpatient, outpatient, and additional courses during readmission or surgery).
Data sources and measurement
Baseline demographic and clinical characteristics, including age, sex, comorbidities, abscess size, and treatment type, were extracted from electronic medical records. Laboratory parameters such as white blood cell (WBC) count, delta neutrophil index (DNI), and C-reactive protein levels were also recorded. The DNI, an automated measure of circulating immature granulocytes, has been reported as a useful inflammatory marker for predicting acute and complicated appendicitis [15].
Bias
This retrospective cohort study is subject to selection bias and confounding by indication because the allocation to NOM versus IA was influenced by clinical status and surgeon preference. Older age and a higher prevalence of comorbidities predominated in the NOM group, whereas larger abscesses and higher inflammatory markers were more common in the IA group. To minimize misclassification, exposures and outcomes were abstracted from electronic medical records using predefined criteria. Recurrent appendicitis was defined as the presence of both symptomatic presentation and imaging confirmation. Follow-up consisted of outpatient visits supplemented with structured telephone interviews, which may have introduced recall bias and differential detection if the intensity of surveillance differed between groups. Because of the imbalanced baseline characteristics and small sample size, advanced adjustment methods such as multivariable modeling or propensity score analysis were not applied, making residual confounding likely. Classification of NOM patients who later underwent surgery as “NOM with recurrence” reduced immortal time bias; however, time-dependent confounding cannot be completely excluded. These limitations are reported to support accurate interpretation of the comparative outcomes.
Study size
This study included an exhaustive sample of all eligible adult patients who underwent PCD for periappendiceal abscess at our center between January 2009 and December 2019; therefore, no a priori sample size calculation was performed. The final cohort consisted of 53 patients (NOM group, n=26; IA group, n=27). The precision of key outcome estimates was limited; for example, the NOM recurrence rate of 7.7% (2 of 26) corresponded to an approximate 95% confidence interval of 2.1% to 24.1%. Accordingly, these estimates should be interpreted with caution and confirmed in larger, prospectively powered studies.
Statistical methods
Baseline characteristics, clinical outcomes, and follow-up periods are presented as medians with interquartile ranges (IQRs) or means with standard deviations, depending on data distribution. Categorical variables are expressed as frequencies and percentages. The Shapiro-Wilk test was used to assess normality. Normally distributed continuous variables were compared using the independent t-test, whereas non-normally distributed variables were analyzed with the Mann-Whitney U-test. Comparisons between the NOM and IA groups for categorical variables were performed using the chi-square test or Fisher exact test, as appropriate. Statistical analyses were conducted using IBM SPSS ver. 23.0 (IBM Corp). A P-value of <0.05 was considered statistically significant.
RESULTS
A total of 53 patients met the inclusion criteria and were included in the analysis: 26 underwent NOM alone, and 27 underwent IA following initial PCD (Fig. 1).
The median follow-up duration was 37 months (IQR, 15–54 months; range, 4–104 months). In the IA group, 19 patients underwent appendectomy during the index hospitalization, while 8 patients had surgery scheduled after discharge during outpatient follow-up. The mean interval between drainage and surgery among these eight patients was 28.88±16.54 days. In contrast, within the NOM group, two patients experienced recurrence and eventually required surgery, but these procedures occurred substantially later, with the earliest surgeries performed 161 and 244 days after drainage. For analytic consistency, recurrent cases were retained in the NOM group and classified as “NOM with recurrence,” rather than reassigned to the IA group.
Patients in the NOM group were significantly older than those in the IA group (62.4±11.5 years vs. 49.5±21.9 years, P=0.007) and had a higher prevalence of comorbidities (76.9% vs. 33.3%, P=0.004). Conversely, the IA group had larger abscesses (5.23±1.64 cm vs. 6.32±1.67 cm, P=0.011) and higher inflammatory markers, including WBC count (11,075.7±5,462.6/mm3 vs. 16,576.7±5,576.5/mm3, P<0.001) and DNI (1.25 [IQR, 0.50–2.05] vs. 2.35 [IQR, 1.33–3.35], P=0.017) (Table 1).
Treatment outcomes differed significantly between groups (Table 2). Patients in the IA group had longer hospital stays (7.9±5.6 days vs. 12.9±6.6 days, P=0.003) and longer total hospitalization durations, including readmissions (9.3±7.8 days vs. 15.3±6.2 days, P=0.002). The duration of intravenous antibiotic therapy was also significantly greater in the IA group (5 days [IQR, 5–9 days] vs. 13 days [IQR, 9–17 days], P<0.001), resulting in a longer total antibiotic treatment period (15 days [12–18 days] vs. 21 days [15–27 days], P=0.005). The duration of drainage did not differ significantly between groups (12.0±7.9 days vs. 14.7±14.7 days, P=0.213). Importantly, no drainage-related complications occurred.
In the NOM group, the recurrence rate of appendicitis was 7.7% (2 of 26). All recurrent cases were successfully treated surgically (Table 3). No malignancies were identified during follow-up. Four patients in the NOM group died from unrelated comorbid conditions (two malignancies, one cerebrovascular event, and one pulmonary disease), reflecting the higher baseline risk profile of this cohort.
DISCUSSION
Key results
This study evaluated the feasibility and outcomes of NOM in patients with periappendiceal abscesses, comparing those managed with NOM alone and those who underwent NOM followed by IA. The findings indicate that NOM is a safe and effective initial approach, with a low recurrence rate of 7.7%. Patients managed with NOM alone experienced shorter hospital stays, shorter antibiotic duration, and avoided surgery, supporting its role as a viable alternative to routine IA in selected cases.
Interpretation and comparison with previous studies
Patients in the NOM group were significantly older and had a higher prevalence of comorbidities compared with those in the IA group, underscoring NOM as a practical option for high-risk patients who may not tolerate surgery well. Conversely, the IA group demonstrated higher inflammatory markers (WBC count and DNI) and larger abscess sizes, suggesting that these parameters may help guide treatment selection. These findings are consistent with previous studies identifying such factors as predictors of the need for surgical intervention or recurrence risk [13,16,17]. Additionally, the significantly longer total duration of antibiotic therapy observed in the IA group reflects greater resource utilization, including extended hospital stays and prolonged intravenous antibiotic administration.
The recurrence rate of 7.7% observed in the NOM group aligns with previous evidence suggesting that NOM alone is sufficient to treat periappendiceal abscesses in most cases [7,8,12,17,18]. In the present study, recurrent cases required extensive surgery, including right hemicolectomy and laparoscopic ileocecectomy, due to unresolved inflammation and recurrent abscess formation. One patient was ultimately diagnosed with diverticulitis rather than recurrent appendicitis. These findings highlight the importance of careful patient selection and close follow-up, as a small subset of patients may eventually require more extensive surgical procedures.
Concerns have also been raised regarding the possibility of missed malignancies, particularly neuroendocrine tumors and appendiceal neoplasms, in patients managed without IA. Historically, IA was often performed to identify incidental malignancies, especially in cases of persistent luminal dilation. For instance, in one study of 18 patients undergoing IA after conservative management, one case (5.6%) of appendiceal neuroendocrine tumors was identified [19,20]. In the present study, no malignancies were detected during follow-up. This outcome supports the growing consensus that routine IA is unnecessary in asymptomatic patients, provided that adequate clinical and radiologic monitoring is maintained.
Recent guidelines, including those issued by the WSES, recommend a selective approach to IA, reserving the procedure for patients with unresolved abscesses, recurrent symptoms, or suspected malignancy [2,13,18]. The current findings are consistent with these recommendations, reinforcing the feasibility and safety of NOM alone in appropriately selected patients. Furthermore, avoiding routine colonoscopy unless malignancy is suspected is consistent with WSES guidance and helps reduce unnecessary interventions while maintaining patient safety [2,8,13].
Although IA has traditionally been considered a safeguard against recurrence or missed malignancy, recent evidence indicates that its routine use may not be warranted. Recurrence rates following NOM are relatively low, and most recurrent cases can be managed effectively with minimal morbidity [21–24]. Moreover, IA itself carries risks, including surgical complications and infections, which call into question its routine role in the management of periappendiceal abscess.
The key findings from this study further highlight the importance of individualized decision-making in clinical practice. While patients with elevated inflammatory markers, larger abscesses, or appendicoliths may benefit from IA, NOM remains an appropriate option for older patients or those with substantial comorbidities. These results emphasize the need for personalized treatment strategies based on clinical presentation, imaging findings, and overall health status [14,25,26].
This study has several strengths. First, it reflects real-world data, capturing practical clinical scenarios and patient-centered decision-making. Patients actively participated in selecting their treatment pathways after receiving thorough explanations of the risks and benefits of each option. Second, the study adopted a selective strategy for surgical intervention, reserving IA for unresolved abscesses or suspected malignancy. This approach aligns with evidence-based guidelines, optimizes resource utilization, and minimizes unnecessary procedures. Third, the inclusion of detailed patient characteristics, laboratory markers, and imaging findings provides valuable data to inform clinical decision-making and patient selection. Finally, the long follow-up period (median, 37 months; range, up to 104 months) offers meaningful insight into recurrence rates and long-term outcomes.
Limitations
This study has several limitations. First, as a retrospective, single-center study, the findings may not be generalizable to other institutions or broader patient populations. Second, baseline characteristics differed between the NOM and IA groups; older age and a higher prevalence of comorbidities were more common in the NOM group, whereas the IA group presented with larger abscesses and higher inflammatory markers. These differences suggest potential confounding. Although propensity score matching or multivariable analysis was considered to adjust for these confounders, the small sample size precluded meaningful adjustment. This limitation should be acknowledged when interpreting the results. Another important limitation is that the study only included patients treated between 2009 and 2019, without incorporating more recent cases. Although the extended study period was intended to maximize the dataset, the number of eligible patients remained limited due to variations in real-world clinical decision-making and institutional treatment approaches. The exclusion of patients from 2020 onward means that more recent developments in periappendiceal abscess management, including updated surgical techniques and refinements in nonoperative strategies, may not be fully represented, potentially affecting the study’s relevance to current practice. Additionally, the relatively small sample size and potential selection bias are notable limitations, as certain patient characteristics may be overrepresented within each treatment group. Treatment decisions were made according to surgeon preference rather than a standardized institutional protocol, introducing variability in patient management. While this reflects real-world clinical practice, it also introduces heterogeneity that future prospective studies should address. Some follow-up data were obtained through telephone interviews, which introduces the possibility of recall bias, particularly for long-term outcomes such as recurrence and survival. Although no malignancies were identified during follow-up, the absence of routine colonoscopy in the NOM group could have delayed detection of rare appendiceal malignancies. Close radiologic and colonoscopic surveillance remains essential to mitigate this risk. Finally, while this study suggests that NOM may reduce hospitalization duration and surgical intervention, healthcare costs were not analyzed directly and should be evaluated in future research.
Conclusions
This study suggests that NOM appears to be a feasible treatment option for periappendiceal abscess, particularly in older or high-risk patients, with IA reserved for unresolved abscesses or recurrent symptoms. Although NOM was associated with shorter hospitalization and reduced antibiotic use, the observed recurrence rate of 7.7% and the small sample size warrant cautious interpretation. Larger, prospective studies are needed to validate these findings and further refine patient selection criteria.
ARTICLE INFORMATION
Author contributions
Conceptualization: all authors; Data curation: all authors; Formal analysis: JGL; Investigation: all authors; Methodology: JGL; Project administration: JGL; Resources: JGL; Supervision: JGL; Validation: JGL, CSP; Visualization: JGL; Writing–original draft: CSP; Writing–review & editing: all authors. All authors read and approved the final manuscript.
Conflicts of interest
The authors have no conflicts of interest to declare.
Funding
The authors received no financial support for this study.
Acknowledgments
The authors would like to acknowledge the contributions of the multidisciplinary care team at our institution for their assistance in patient management and follow-up.
Data availability
Data analyzed in this study are available from the corresponding author upon reasonable request.
Fig. 1.
Flowchart of patient selection. PCD, percutaneous drainage; NOM, nonoperative management, IA, interval appendectomy. aIdentified from electronic medical record using keywords "((periappendiceal abscess) or (pertorated appendicitis)) AND percutaneous drainage)."
Table 1.
Characteristic of enrolled patients (n=53)
Characteristic
NOM group (n=26)
IA group (n=27)
P-value
Age (yr)
62.4±11.5
49.5±21.9
0.007
Sex
0.320
Male
15 (57.7)
11 (40.7)
Female
11 (42.3)
16 (59.3)
No. of comorbidities
0.004
0
6 (23.1)
18 (66.7)
1
10 (38.5)
7 (25.9)
2
8 (30.8)
2 (7.4)
3
2 (7.7)
0 (0)
Charlson Comorbidity Index
2.81±1.77
1.36±1.70
0.005
Largest diameter of abscess (cm)
5.23±1.64
6.32±1.67
0.011
CRP level (mg/dL)
150.6 (70.9–192.2)
143.9 (105.4–234.4)
0.140
WBC count (/mm3)
11,075.7±5,462.6
16,576.7±5,576.5
<0.001
Delta neutrophil index
1.25 (0.50–2.05)
2.35 (1.33–3.35)
0.017
Antibiotic
NS
Tazobactam/piperacillin
20 (76.9)
22 (81.5)
Second-generation cephalosporin±antianaerobic
2 (7.7)
3 (11.1)
Third-generation cephalosporin+antianaerobic
3 (11.5)
2 (7.4)
Quinolone+antianaerobic
1 (3.8)
0 (0)
Values are presented as number (%), mean±standard deviation, or median (iterquartile range). Percentages may not total 100 due to rounding.
NOM, nonoperative management; IA, interval appendectomy; CRP, C-reactive protein; WBC, white blood cell count; NS, not significant.
Table 2.
Comparison of clinical outcomes (n=53)
Outcome
NOM group (n=26)
IA group (n=27)
P-value
Readmission (for surgery)
2 (7.7)
8 (29.6)
-
Duration of hospitalization (day)
Initial
7.9±5.6
12.9±6.6
0.003
Readmission (n=2 vs. n=8)
17.5±16.3
7.4±4.9
0.269
Total (initial+readmission)
9.3±7.8
15.3±6.2
0.002
Duration of drainage (day)
12.0±7.9
14.7±14.7
0.213
Drainage to surgery (day) (n=2 vs. n=27)
202.5±18.7
14.7±14.7
0.068
Duration of antibiotics (day)
Intravenous
5 (5–9)
13 (9–17)
<0.001
Oral
9.91±5.22
10.52±6.31
0.734
Total
15 (12–18)
21 (15–27)
0.005
Values are presented as number (%), mean±standard deviation, or median (iterquartile range).
Cases of operative management for recurrence after nonoperative management
Case no.
Sex
Age (yr)
Duration of drainage (day)
Drainage to surgery (day)
Operation
Pathology
1
Male
61
17
160
Right hemicolectomy
Inflammation
2
Male
43
15
244
Laparoscopic ileocecectomy
Inflammation, diverticulitis
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17. Tsai HM, Shan YS, Lin PW, Lin XZ, Chen CY. Clinical analysis of the predictive factors for recurrent appendicitis after initial nonoperative treatment of perforated appendicitis. Am J Surg 2006;192:311–6.
18. Habeeb TA, Hussain A, Schlottmann F, et al. Recurrent appendicitis following successful drainage of appendicular abscess in adult without interval appendectomy during COVID-19. Prospective cohort study. Int J Surg 2022;97:106200.
19. Pogorelić Z, Ercegović V, Bašković M, Jukić M, Karaman I, Mrklić I. Incidence and management of appendiceal neuroendocrine tumors in pediatric population: a bicentric experience with 6285 appendectomies. Children (Basel) 2023;10:1899.
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26. Mällinen J, Rautio T, Grönroos J, et al. Risk of appendiceal neoplasm in periappendicular abscess in patients treated with interval appendectomy vs follow-up with magnetic resonance imaging: 1-year outcomes of the Peri-Appendicitis Acuta randomized clinical trial. JAMA Surg 2019;154:200–7.
Comparison of outcomes of nonoperative management with versus without interval appendectomy for periappendiceal abscess in Korea: a retrospective cohort study
Fig. 1. Flowchart of patient selection. PCD, percutaneous drainage; NOM, nonoperative management, IA, interval appendectomy. aIdentified from electronic medical record using keywords "((periappendiceal abscess) or (pertorated appendicitis)) AND percutaneous drainage)."
Graphical abstract
Fig. 1.
Graphical abstract
Comparison of outcomes of nonoperative management with versus without interval appendectomy for periappendiceal abscess in Korea: a retrospective cohort study
Characteristic
NOM group (n=26)
IA group (n=27)
P-value
Age (yr)
62.4±11.5
49.5±21.9
0.007
Sex
0.320
Male
15 (57.7)
11 (40.7)
Female
11 (42.3)
16 (59.3)
No. of comorbidities
0.004
0
6 (23.1)
18 (66.7)
1
10 (38.5)
7 (25.9)
2
8 (30.8)
2 (7.4)
3
2 (7.7)
0 (0)
Charlson Comorbidity Index
2.81±1.77
1.36±1.70
0.005
Largest diameter of abscess (cm)
5.23±1.64
6.32±1.67
0.011
CRP level (mg/dL)
150.6 (70.9–192.2)
143.9 (105.4–234.4)
0.140
WBC count (/mm3)
11,075.7±5,462.6
16,576.7±5,576.5
<0.001
Delta neutrophil index
1.25 (0.50–2.05)
2.35 (1.33–3.35)
0.017
Antibiotic
NS
Tazobactam/piperacillin
20 (76.9)
22 (81.5)
Second-generation cephalosporin±antianaerobic
2 (7.7)
3 (11.1)
Third-generation cephalosporin+antianaerobic
3 (11.5)
2 (7.4)
Quinolone+antianaerobic
1 (3.8)
0 (0)
Outcome
NOM group (n=26)
IA group (n=27)
P-value
Readmission (for surgery)
2 (7.7)
8 (29.6)
-
Duration of hospitalization (day)
Initial
7.9±5.6
12.9±6.6
0.003
Readmission (n=2 vs. n=8)
17.5±16.3
7.4±4.9
0.269
Total (initial+readmission)
9.3±7.8
15.3±6.2
0.002
Duration of drainage (day)
12.0±7.9
14.7±14.7
0.213
Drainage to surgery (day) (n=2 vs. n=27)
202.5±18.7
14.7±14.7
0.068
Duration of antibiotics (day)
Intravenous
5 (5–9)
13 (9–17)
<0.001
Oral
9.91±5.22
10.52±6.31
0.734
Total
15 (12–18)
21 (15–27)
0.005
Case no.
Sex
Age (yr)
Duration of drainage (day)
Drainage to surgery (day)
Operation
Pathology
1
Male
61
17
160
Right hemicolectomy
Inflammation
2
Male
43
15
244
Laparoscopic ileocecectomy
Inflammation, diverticulitis
Table 1. Characteristic of enrolled patients (n=53)
Values are presented as number (%), mean±standard deviation, or median (iterquartile range). Percentages may not total 100 due to rounding.
NOM, nonoperative management; IA, interval appendectomy; CRP, C-reactive protein; WBC, white blood cell count; NS, not significant.
Table 2. Comparison of clinical outcomes (n=53)
Values are presented as number (%), mean±standard deviation, or median (iterquartile range).
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