Incidence and Risk Factors for Tuberculosis After Liver Transplantation in an Endemic Area: A Nationwide Population-Based Matched Cohort Study.

Morbidity and mortality from tuberculosis (TB) are high in Taiwan. We conducted a nationwide population-based matched cohort study using data retrieved from the Taiwan's National Health Insurance Research Database to determine the impact of TB after liver transplantation (LT). During 2000-2011, we identified 3202 liver transplant recipients and selected subjects from the general population matched for age, sex, and comorbidities on the same index date of recognition of LT with a 1:10 ratio. The data were analyzed using Cox proportional hazards models. Compared to the matched cohort, liver transplant patients had a higher risk for TB (adjusted HR 2.25, 95% CI 1.65-3.05, p < 0.001), and those with TB showed higher mortality (HR 2.27, 95% CI 1.30-3.97, p = 0.004). Old age (HR 2.64, 95% CI 1.25-5.54, p = 0.011) and mammalian target of rapamycin inhibitors (mTORis) (HR 3.09, 95% CI 1.68-5.69, p < 0.001) were significant risk factors for TB in LT; mTORis were also associated with mortality after adjusting for confounders (HR 2.13, 95% CI 1.73-2.62, p < 0.001). Therefore, regular surveillance of TB and treatment of latent TB infection in high-risk patients after LT are important, especially in TB-endemic areas.

A prognostic model for patients with hepatocellular carcinoma within the Milan criteria undergoing non-transplant therapies, based on 1106 patients.

BACKGROUND: The Milan criteria are used to select candidates with small hepatocellular carcinoma (HCC) for liver transplantation. Due to severe shortage of donors, majority of patients within the Milan criteria need to seek alternative treatments. AIM: To propose a prognostic model for these patients undergoing non-transplant therapies. METHODS: A total of 1106 HCC patients, who were within the Milan criteria and received non-transplant therapies were retrospectively analysed. Patients were randomly assigned to the derivation and validation set according to treatments. A prognostic model was constructed from independent predictors of survival identified in the multivariate Cox model of the derivation set and was confirmed in the validation set. RESULTS: In the Cox model, serum bilirubin ≥1.5 mg/dL [risk ratio (RR): 1.525, P = 0.016], α-fetoprotein (AFP) ≥100 ng/mL (RR: 1.728, P < 0.001), mild ascites (RR: 1.705, P = 0.025) and moderate/severe ascites (RR: 4.163, P < 0.001) were independent predictors of poor survival in the derivation set (n = 553). A prognostic model with a total of 0-4 points was derived with the sum of three variables: 1 point each for bilirubin ≥1.5 mg/dL, AFP ≥100 ng/mL and mild ascites, and 2 points for moderate/severe ascites. This scoring system accurately predicted the survival in the validation set (n = 553; P < 0.001). The model consistently discriminated the survival in patients stratified by curative and noncurative treatments (both P values <0.001). CONCLUSION: The newly proposed prognostic scoring model, based on serum bilirubin and AFP level, and severity of ascites, is informative to predict the survival in non-transplant HCC patients within the Milan criteria.

Changes in mitochondrial respiratory enzyme activity after ischemia-reperfusion injury in living-donor liver transplantation.

BACKGROUND: Ischemia-reperfusion (I-R) injury plays an important role in the immediate graft function in living-donor liver transplantation (LDLT). There is growing evidence that mitochondria play a pivotal role in I-R injury. Our aim was to evaluate changes in mitochondrial respiratory enzyme activities after I-R injury in LDLT. METHODS: Specimens from 8 donor recipient pairs enrolled in this study were obtained from the donor livers before harvest (before I-R injury) and after vascular anastomosis in the recipient (after I-R injury). Histidine-tryptophan-ketoglutarate solution was used to perfuse the organ during the cold ischemic period between harvesting and transplantation. We correlated changes in mitochondrial respiratory enzyme complex activity (succinate cytochrome c reductase [SCCR]; NADH cytochrome c reductase [NCCR]) after I-R injury with clinical data and graft status. RESULTS: NCCR and SCCR activities did not uniformly decrease after I-R injury. Two of 8 recipients experienced graft dysfunction after transplantation. The decrease in neither NCCR nor SCCR activity correlated with graft dysfunction in these 2 patients. Among the clinical factors, grafts from older donors tended to show decreased NCCR activity after I-R injury. CONCLUSIONS: In this study, changes in mitochondrial respiratory enzyme activity failed to predict the severity of I-R injury in LDLT. The organ preservation solution may play a protective role on mitochondrial respiratory enzymes during I-R injury.

The MELD-Na is an independent short- and long-term prognostic predictor for hepatocellular carcinoma: a prospective survey.

BACKGROUND AND AIM: Serum sodium has been suggested to incorporate into the model for end-stage liver disease to enhance its prognostic ability for cirrhosis. A mathematical equation based on model for end-stage liver disease and sodium, known as "MELD-Na", was developed for outcome prediction for cirrhosis. The severity of liver cirrhosis is a key component to predict survival in patients with hepatocellular carcinoma. This study investigated the prognostic role of MELD-Na for hepatocellular carcinoma. PATIENTS AND METHODS: A total of 535 unselected hepatocellular carcinoma patients were prospectively enrolled to evaluate the performance of MELD-Na. RESULTS: The MELD-Na was better than model for end-stage liver disease in predicting 6-month mortality by comparing the area under receiver operating characteristic curve (0.782 vs. 0.761, p=0.101). MELD-Na, but not model for end-stage liver disease, was an independent predictor associated with 6-month mortality in multivariate logistic regression analysis (odds ratio: 1.14, p=0.001). In the survival analysis, MELD-Na also independently predicted mortality, with an additional risk of 4.3% per unit increment of the score (p<0.001). Patients with MELD-Na scores between 10 and 20 and scores >20 had 2.1-fold (p<0.001) and 7.5-fold (p<0.001) risk of mortality, respectively, compared to patients with a score <10 in the Cox proportional hazard model. CONCLUSION: The MELD-Na score is a feasible and independent prognostic predictor for both short- and long-term outcome predictions in patients with hepatocellular carcinoma.

Supradiaphragmatic ectopic liver: delayed traumatic hepatic hernia mimics pulmonary tumor.

We present a rare case of a 63-year-old woman, the oldest one in the literature, with supradiaphragmatic ectopic liver that mimics a pulmonary nodule. The chest roentgenogram and chest computer tomography showed a lobulated tumor nearby the diaphragm. Pathological examination of the resected tumor disclosed only remarkable fatty liver change. Ectopic liver should be kept in mind to differentiate for the pulmonary tumor nearby the diaphragm.

Evaluation of interleukin-6, interleukin-10 and human hepatocyte growth factor as tumor markers for hepatocellular carcinoma.

AIM: Serum alpha-fetoprotein (AFP) is the most important tumor marker for hepatocellular carcinoma (HCC). Previous reports indicated that HCC was also associated with increased levels of interleukin (IL)-6, IL-10 and hepatocyte growth factor (HGF). This study investigated the role of these cytokines as tumor markers for HCC. METHOD: A total of 128 adults were prospectively enrolled and categorized into four groups: normal subjects (n=29), chronic hepatitis B or C (n=50), non-HCC tumors (n=23) and HCC (n=26). Serum AFP, IL-6, IL-10 and HGF levels were determined in all subjects. RESULTS: The expression of IL-6 or IL-10 (> or =3 pg/ml), or high level of HGF (>1000 pg/ml) or AFP (>20 ng/ml) was observed in only 0-3% of normal subjects. Patients with HCC more frequently had higher IL-6 and IL-10 levels (p<0.05), whereas HGF levels in HCC patients were not significantly elevated compared to patients with chronic hepatitis or non-HCC tumors. Among patients with low (<20 ng/ml) AFP level, IL-6 or IL-10 expression was significantly associated with the existence of HCC (p<0.05). Patients with large (>5 cm) HCC more often had increased IL-6, IL-10 or AFP levels (p values all <0.05). CONCLUSIONS: Serum levels of IL-6 and IL-10 are frequently elevated in patients with HCC but not in benign liver disease or non-HCC tumors. IL-6 and IL-10 may help identify a subset of HCC patients with low AFP level, and may serve as complementary tumor markers in these patients.

ENDO-GIA staplers for side-to-side anastomosis of veins.

OBJECTIVE: To study the application of ENDO-GIA staplers for the side-to-side anastomosis of veins. MATERIALS AND METHODS: An animal study was conducted. Five dogs received side-to-side anastomosis of allograft IVC by ENDO-GIA staplers (Group 1). In addition, five received the same operation with right renal vein reimplantation to allograft IVC (Group 2). Five dogs, receiving the same operation as in Group 1 using polypropylene sutures (control group, Group 3). An autopsy was performed if the dogs survived more than 8 weeks. RESULTS: The IVC anastomosis remained patent in four subjects (80%) for Group 1, in five subjects (100%) for Group 2 and in four subjects (80%) for Group 3. CONCLUSIONS: From the results of our experiment, ENDO-GIA staplers can be considered for use in the side-to-side anastomosis of large veins such as piggyback cavacaval side-to-side anastomosis in cadaveric orthotopic liver transplantation (OLT) or side-to-side splenorenal shunt in portal hypertension.

Clinicopathologic and prognostic differences between patients with hepatitis B- and C-related resectable hepatocellular carcinoma.

BACKGROUND AND PURPOSE: Hepatitis B and C viral infections are important factors in the development of hepatocellular carcinoma (HCC). This study examined the clinicopathologic and prognostic differences in patients with hepatitis B- and C-related resectable HCC. METHODS: A total of 270 HCC patients who underwent hepatic resection were enrolled. Among these patients, 211 were positive for hepatitis B surface antigen (HBsAg) and 59 were positive for anti-hepatitis C virus antibody (anti-HCV). The clinical manifestations, pathologic features, and treatment outcomes were compared between the HBsAg-positive and anti-HCV-positive groups. RESULTS: Compared to anti-HCV-positive patients, HBsAg-positive patients were significantly younger, had a higher familial incidence of HCC, larger tumor size, and a higher incidence of multiple tumors. HCC patients who were anti-HCV positive had worse liver function and a higher incidence of history of blood transfusion. DNA flow cytometric analysis revealed significantly more proliferative activity in the non-tumor part of the liver in HBsAg-positive HCC patients. The 1-, 3-, and 5-year overall survival rates of HBsAg-positive patients were 79%, 57%, and 48%, respectively, and for anti-HCV-positive patients were 91%, 75%, and 62%, respectively. HBsAg-positive patients had a significantly lower overall survival rate than anti-HCV-positive patients (p = 0.018). CONCLUSIONS: HBsAg-positive patients with resectable HCC had a less favorable survival rate after tumor resection than anti-HCV-positive HCC patients. This survival difference might have been related to the relatively advanced stage of disease and the higher proliferative activity of the non-tumor part of the liver in HBsAg-positive HCC patients.

c-Rel is required for the protection of B cells from antigen receptor-mediated, but not Fas-mediated, apoptosis.

The NF-kappaB/Rel transcription factor family has been shown to protect many cell types from apoptotic signals. However, it is not known whether NF-kappaB is required for all survival pathways and whether each NF-kappaB member plays a unique or a redundant role. Here we describe the results of studies on the role of c-Rel in survival. Mature B cells from c-Rel(-/-) mice exhibit defects in survival, including sensitivity to Ag receptor-mediated apoptosis as well as increased sensitivity to ionizing radiation and glucocorticoids. Transgene expression of Bcl-x(L), a c-Rel target gene, rescues c-Rel(-/-) B cells from their survival defects. Thus, c-Rel-dependent survival pathways are crucial for protection from apoptotic signals that target the mitochondrial pathway. Despite a lack of Bcl-x(L), c-Rel(-/-) B cells can still be rescued from Fas-mediated apoptosis via B cell receptor signaling. The Fas apoptosis inhibitor molecule and FLICE inhibitory protein (c-FLIP) proteins are up-regulated normally in c-Rel(-/-) B cells, and these two molecules may play a more physiological role in the Fas pathway. Furthermore, unlike the TNF sensitivity of RelA(-/-) fibroblasts, c-Rel-deficient fibroblasts are refractory to TNF-mediated cell death. Thus, c-Rel is dispensable for protection against death receptor-mediated apoptosis. Taken together, our data suggest that distinct NF-kappaB/Rel members are required for protecting cells from different types of apoptotic signals.

A progressive growing inflammatory pseudotumor of the liver.

Inflammatory pseudotumors of the liver are very rare, and their etiology and pathogenesis remain unclear. The diagnosis is often difficult to make because these masses often mimic other lesions such as primary neoplasms, metastases or liver abscesses. Herein, we report a rare case of progressive growing hepatic pseudotumor in a 47-year-old man. The patient presented with body weight loss and general malaise. A series of radiological examinations showed the progressive growth of the hepatic tumor from 3.5 cm to 10.0 cm in diameter within 8 months. He underwent a right lobectomy of the liver, and the final diagnosis was proven by pathology. There were no complications in the post-operative course.

Clinical significance of microscopic tumor venous invasion in patients with resectable hepatocellular carcinoma.

BACKGROUND: Tumor venous invasion in patients with resectable hepatocellular carcinoma (HCC) is frequent and can be macroscopic and microscopic or microscopic alone. Although macroscopic invasion is a well-established prognostic indicator, the clinical significance of microscopic invasion remains unclear. METHODS: There were 322 patients enrolled who had undergone curative resection for HCC. The clinicopathologic factors and prognostic significance associated with macroscopic and microscopic venous invasion were analyzed. RESULTS: Macroscopic invasion was observed in 50 patients (15.5%) and microscopic invasion in 190 (59.0%). The larger the tumor, the more the incidence of venous invasion. There were 140 patients with microscopic invasion only (Group 1). Patients with macroscopic invasion (Group 2, n = 50) also had microscopic invasion. Compared with patients without venous invasion (Group 3, n = 132), Group 1 had a higher alpha-fetoprotein level, a larger tumor size, and more tumors without encapsulation. For group 1, the 1-, 3-, and 5-year disease-free survival rates were 65.6%, 41.6%, and 30.8%, respectively. The 1-, 3-, and 5-year overall survival rates were 87. 8%, 60.0%, and 52.7%, respectively. The survival rates of group 1 were lower than those of group 3 and higher than those of group 2 (P <.05). Multivariate analysis indicated that microscopic and macroscopic venous invasion, surgical margin, indocyanine-green retention, and tumor size and number were significant predictors of postresectional survival. CONCLUSIONS: In HCC patients, microscopic venous invasion is frequent and related independently to postresectional outcome.

Perioperative safety and prognosis in hepatocellular carcinoma patients with impaired liver function.

BACKGROUND: The benefits of liver resection for hepatocellular carcinoma (HCC) patients with concomitant impaired liver function were often considered questionable because of poor postoperative prognosis. This study will clarify whether an acceptable operative risk exists and whether limited resection will compromise the outcomes of these patients. STUDY DESIGN: Between July 1991 and December 1996, a total of 168 patients with HCC who underwent hepatectomies were enrolled and divided into normal (group A) and impaired (group B) liver function groups according to the value of indocyanine green retention rate at 15 minutes. Clinical features, surgical related features, pathologic features, and disease-free and overall survivals were compared between the groups. RESULTS: Operative morbidity and mortality in group A were 27.3% and 1.6%, and in group B were 40.0% and 2.5%, respectively (p = 0.129 and 0.506). Disease-free survival and overall survival at 5 years in group A were 43.2% and 59.6%, respectively, and in group B they were 30.6% and 56.8%, respectively (p = 0.607 and 0.378). CONCLUSIONS: Limited liver resection is safe and provides favorable prognosis in HCC patients with concomitant impaired liver function.

Serum interleukin-10 but not interleukin-6 is related to clinical outcome in patients with resectable hepatocellular carcinoma.

OBJECTIVE: To evaluate the clinical significance of preoperative serum levels of interleukin-10 (IL-10) and interleukin-6 (IL-6) in patients with resectable hepatocellular carcinoma (HCC). SUMMARY BACKGROUND DATA: IL-10 is an immunosuppressive factor and IL-6 is a multifunctional cytokine that plays a role in host defense mechanisms. Both have been reported to be related to the disease prognosis in some human solid tumors. Their role in human HCC has not been investigated. METHODS: Preoperative serum samples of 67 patients with HCC who underwent potentially curative resection and 27 normal healthy donors were assayed. Levels of IL-10 and IL-6 were determined by enzyme-linked immunosorbent assay. The clinical significance of serum IL-10 and IL-6 was evaluated and compared with conventional clinicopathologic factors. RESULTS: Levels of IL-10 and IL-6 were significantly higher in patients with HCC than in healthy subjects. There was no correlation between IL-10 and IL-6 levels. Tumor resection resulted in a decrease in IL-10 and IL-6 levels. On univariate analysis, patients with high IL-10 levels had a worse disease-free survival, but IL-6 levels had no correlation with the disease-free survival. Multivariate analysis identified IL-10 levels as a predictor of postresectional outcome, in addition to the well-established clinical risk factors. CONCLUSIONS: In patients with HCC, the preoperative serum IL-10 level is related to the clinical outcome. IL-10 may play an important role in the progression of HCC.

Surgical results in patients with hepatitis B-related hepatocellular carcinoma and positive hepatitis B early antigen.

Hepatitis B virus (HBV) infection is the major risk factor in the pathogenesis of hepatocellular carcinoma (HCC). Patients who are positive for hepatitis B early antigen (HBeAg) have active liver disease. The present study aimed to evaluate the possible role of HBeAg in patients with resectable HCC. A series of 249 HCC patients with complete preoperative hepatitis marker who had undergone potentially curative resection were enrolled. Patients with hepatitis C virus infection were excluded. Of these patients, 27 were positive for hepatitis B surface antigen (HBsAg) and HBeAg (group I), 171 were positive for HBsAg and negative for HBeAg (group II), and 51 were negative for hepatitis B markers (group III). The clinicopathologic features and postoperative survivals were compared among the three groups. The prevalence of HBeAg was 10.8%. Group I patients were significantly younger and had worse liver function, smaller tumors, and a higher incidence of liver cirrhosis and chronic active hepatitis than those in groups II and III. No increase in tumor invasiveness was noted in group I patients. The operative morbidity, mortality, and postresection survival were comparable among the three groups. Our findings indicated that HBeAg positivity is not a negative factor for resection in HCC patients and has no significant influence on postresection survival.

Evaluation of a simplified staging system for prognosis of hepatocellular carcinoma.

The current TNM (tumor, nodes, metastases) staging system for human hepatocellular carcinoma (HCC) has been challenged since a new T staging system was proposed to correlate the staging group with patient outcome after curative liver resection. The new T staging system proposed T1 as no vascular invasion, small size (< or = 5 cm), and solitary tumor. T2 was defined as the presence of one of the following factors: size greater than 5 cm, vascular invasion, or multiple tumors; T3 as the presence of two of the above three factors; and T4, the presence of all three factors. A total of 323 patients undergoing curative partial hepatectomy for HCC were studied. Kaplan-Meier survival analysis was used to evaluate the postoperative outcome. The new T staging showed good correlation between the staging group and patient outcome. The 1-year disease-free survival (DFS) rate and overall survival (OS) rate were 80.0% and 87.8% for stage 1 (n = 115), 67.6% and 81.6% for stage 2 (n = 136), 40.0% and 58.0% for stage 3 (n = 58), and 21.4% and 42.8% for stage 4 (n = 14), respectively. The 3-year DFS rate and OS rate were 61.0% and 64.5% for stage 1, 37.8% and 50.7% for stage 2, 21.4% and 29.8% for stage 3, and 21.4% and 34.3% for stage 4, respectively. When analyzed using the current International Union Against Cancer (UICC) pathologic (p) TNM staging system, the 1-year and 3-year DFS rates were 86.2% and 64.0% for stage 1 (n = 30), 73.9% and 50.0% for stage 2 (n = 182), and 46.8% and 22.3% for stage 3 (n = 111), respectively. Our results showed that, while both staging systems allow clear stratification of patients into prognostic groups, the modified TNM system is not superior to the UICCpTNM system in predicting survival of HCC patients after curative partial hepatectomy. A larger scale, multicenter study may be needed to test the revised TNM system.

Heterotopic pancreas: a difficult diagnosis.

Heterotopic pancreas is a rare disease. We evaluated 17 patients treated surgically at our hospital. Epigastric pain (77%), abdominal fullness (30%), and tarry stools (24%) were the three most frequent symptoms and signs. The lesions were diagnosed as gastroduodenal tumors by gastroduodenoscopy (67%) or upper gastrointestinal series (71%). Among these, only one gastric submucosal tumor was considered to be heterotopic pancreas preoperatively. Three patients were found to have gastric tumor by abdominal ultrasound. Computed tomography, small-intestinal series, barium enema, endoscopic retrograde cholangiopancreatography, angiography, and cholescintigraphy did not help in disclosing lesion. In about half of the patients, the lesions were located at the stomach. Tumor size varied from 1 to 3 cm. Surgical excision relieved symptoms. These findings indicated heterotopic pancreas is still a difficult disease for diagnosis, regardless of the improvements of diagnostic tools and techniques.

Factors correlated with number of metastatic lymph nodes in gastric cancer.

OBJECTIVE: We had previously reported a reasonable categorization of the number of positive lymph nodes (LN: 0, 1-4, 5-8, and > 8) as a prognostic indicator. This study was an extension, to see which factors correlated with number of positive lymph nodes. METHODS: A total of 533 patients with gastric adenocarcinoma, who underwent curative surgery between January 1988 and December 1995, were entered into this study. Patients were divided into four groups according to metastatic LN number (0, 1-4, 5-8, and > 8). Their survival and clinicopathological factors were analyzed. RESULTS: A total of 16,457 LNs, with an average of 30.9 per specimen, were removed, of which 1686 (10.2%) showed metastases. The 5-yr cumulative survival rate decreased as the number of metastatic LNs increased, ie., 91.3% for LN 0; 67.4% for LN 1-4; 37.2 for LN 5-8, and 14.1% for LN > 8. Multivariate analyses showed that depth of cancer invasion (odds ratio: 2.4), gross appearance (odds ratio: 1.9), size (odds ratio: 1.9), and location (odds ratio: 1.4) of tumor were four independent factors correlated with the number of metastatic LNs. Number of metastatic LNs increased with advanced Japanese nodal stage and UICC-TNM stage. CONCLUSIONS: Depth of tumor invasion, and gross appearance, size, and location of tumor were four pathological factors independently correlated with number of metastatic LNs in gastric cancer.

Active-site titration of serine proteases using a fluoride ion selective electrode and sulfonyl fluoride inhibitors.

We report a general procedure for the determination of active enzyme concentrations for serine proteases. The method relies on the measurement of fluoride ion released from sulfonyl fluorides upon reaction with the active-site serine using an ion selective electrode. The results have been independently confirmed by amino acid analyses of subtilisins and by spectrofluorometric and spectrophotometric titrations. The minimal enzyme concentration detectable is 1-10 microM protease. The method is insensitive to color and turbidity of the sample and is therefore useful for measuring protease concentration in broth solutions. The active enzyme concentration of subtilisin BPN' from Bacillus amyloliquefaciens determined by titration with phenylmethylsulfonyl fluoride is 25% higher than the concentration determined using the spectrophotometric burst titrant N-trans-cinnamoylimidazole. Analysis of the pre-steady-state burst amplitude and kinetics suggests that the extinction coefficient for the cinnamoyl acyl-enzyme is larger than previously measured and a significant fraction of the enzyme is present as an unproductive ES2 complex. The molar extinction coefficient at 280 nm for subtilisin BPN' is 26.5 mM-1 cm-1 and for subtilisin from Bacillus lentus is 22.5 mM-1 cm-1.

Elective interval laparoscopic management for periappendiceal abscess.

BACKGROUND: In Far Eastern countries, the right-sided colonic diverticular diseases are more prevalent than the left-sided ones. Accurate differential diagnosis between appendiceal abscess and right-sided diverticulitis with abscess formation is difficult to make preoperatively. Conservative treatment followed by elective interval surgery remains the mainstay of management for patients with periappendiceal abscess. Laparoscopic diagnosis and treatment have been advocated in managing patients with abdominal pain of uncertain diagnosis. The purpose of this study was to evaluate the beneficial effect of interval barium enema and mini-invasive procedures for patients with periappendiceal abscess. METHODS: Patients with periappendiceal abscess (n = 8) were enrolled in this study. Conservative treatment was instituted by administration of antibiotics, and interval barium enema and laparoscopic intervention were scheduled later. Clinical manifestations, results of barium enema, outcomes of laparoscopic intervention and pathological diagnoses were reviewed. RESULTS: The frequency of periappendiceal abscess was 18/263 (6.8%). There were no operative complications. The correlation between barium enema, laparoscopic findings, and pathological diagnosis was quite good. Patients gained the advantages of laparoscopic surgery. CONCLUSIONS: Interval barium enema study and laparoscopic diagnosis and treatment are worthy of trying for patients with periappendiceal abscess, especially in those areas with high prevalence of right-sided diverticular diseases.