Splenectomy Correlates With Increased Risk of Pyogenic Liver Abscess: A Nationwide Cohort Study in Taiwan

Clinical characteristics and management of 106 patients with pyogenic liver abscess in a traditional Chinese hospital

This is a retrospective study of clinical data from 106 patients with pyogenic liver abscess (PLA) treated in a traditional Chinese hospital during the eight years preceding this publication. We aimed to provide evidence to improve the diagnosis accuracy and the treatment strategies for PLAs. We collected records of patients treated at the Guangxing Hospital, which is affiliated to the Zhejiang Traditional Chinese University in Hangzhou, and we collected their general background information, laboratory and imaging features, and clinical manifestations and outcomes to perform a retrospective analysis. Diabetes mellitus (45.3%, 48/106), biliary calculi (36.8%, 39/106), and history of abdominal surgery (15.1%, 16/106) were the three most common PLA risk factors present in our cohort. Fever and chills (95.3%, 101/106), right upper quadrant pain/epigastric discomfort (68.9%, 73/106), nausea and vomiting (38.8%, 41/106), and cough and sputum (14.2%, 15/106) were the most common clinical manifestations of PLA. Most patients had the abscesses in the right liver lobe, and the most commonly found bacteria were Klebsiella pneumoniae (54.8%, 42/76), Escherichia coli (35.1%, 27/76), and Streptococcus pneumoniae (3.9%, 3/76). Liver Doppler ultrasound is a conventional and effective method to identify liver abscesses. Most patients were treated using a percutaneous puncture under B-ultrasound guidance. Most patients (n = 104 or 98.1%) were cured, one patient (0.9%) died, and one was discharged with multiple abscesses post treatment.

Outcomes of Infection and Risk of Mortality in Liver Transplant Patients with Simultaneous Splenectomy

PURPOSE

The purpose of this study was to compare the outcomes of infection between liver transplant patients with and without simultaneous splenectomy.

METHODS

We retrospectively analyzed the records of 211 patients who underwent liver transplantation in the Tri-Service General Hospital from 2012 to 2017. The frequency of blood cultures obtained after liver transplantation; incidence of bacteremia, pathogens, and complications; and overall survival rates were compared between the groups.

RESULTS

One hundred thirty-three of 211 patients underwent liver transplantation without simultaneous splenectomy. There were no significant differences in the frequency of blood cultures obtained after liver transplantation (non-splenectomy group and splenectomy group: 63% and 62%, respectively); incidences of bacteremia after liver transplantation (21% and 21%, respectively), repeat bacteremia (39% and 35%, respectively), cytomegalovirus infection (4% and 3%, respectively), herpes infection (6% and 7%, respectively), and fungal infection (3% and 3%, respectively); and overall survival rate between the two groups. However, there was a significant difference in infection-related deaths between the groups. Simultaneous splenectomy and episodes of antibody-related rejection were significant risk factors associated with infection-related death in multivariate analyses.

CONCLUSION

Although simultaneous splenectomy does not increase the incidence of infection, simultaneous splenectomy definitely carries risks of infection-related mortality in liver transplantation.

Abnormalities of the composition of the gut microbiota and short-chain fatty acids in mice after splenectomy

The brain–gut–microbiota axis is a complex multi-organ bidirectional signaling system between the brain and microbiota that participates in the host immune system. The spleen, as the largest immune organ in the body, has a key role in the brain–gut–microbiota axis. Here, we investigated whether splenectomy could affect depression-like phenotypes and the composition of the gut microbiota in adult mice. In behavioral tests, splenectomy did not cause depression-like behaviors in mice. Conversely, splenectomy led to significant alterations in the diversity of gut microbes compared with the findings in control (no surgery) and sham-operated mice. In an unweighted UniFrac distance analysis, the boxplots representing the splenectomy group were distant from those representing the other two groups. We found differences in abundance for several bacteria in the splenectomy group at the taxonomic level compared with the other two groups. Finally, splenectomy induced significant changes in lactic acid and n-butyric acid levels compared with those in the other groups. Interestingly, there were significant correlations between the counts of certain bacteria and lactic acid (or n-butyric acid) levels in all groups. These data suggest that splenectomy leads to an abnormal composition of the gut microbiota. It is likely that the spleen–gut–microbiota axis plays a crucial role in the composition of the gut microbiota by regulating immune homeostasis.

Pediatric Liver Abscess: Trends in the Incidence, Etiology, and Outcomes Based on 20-Years of Experience at a Tertiary Center

Background: Liver abscess is an important but relatively rare disease in children. This study investigated the clinical characteristics of eligible patients at a referral tertiary center over the past two decades. Method: A 20-year retrospective study (January 2000-December 2019) enrolled 38 children diagnosed with liver abscess. Demographic data; clinical features; laboratory, imaging, and microbiological findings; management strategy; and outcomes were reviewed from the patients' medical records. Results: Thirty-eight cases of pyogenic liver abscess were identified without a culture-proven amebic or fungal abscess. The mean age of diagnosis was 9.6 ± 6.2 years, and the male-to-female ratio was 1.92: 1. Hemato-oncological (28.9%) and predisposing hepatobiliary diseases (23.7%) were the two most common predisposing factors. Fever (94.7%) was the most common presentation followed by right upper quadrant abdominal pain (42.1%) and pleural effusion (34.2%). Among the laboratory parameters, leukocytosis was common (70.3%), and all patients had elevated serum C-reactive protein levels. Increased serum levels of alanine aminotransferase, aspartate aminotransferase, direct bilirubin, and total bilirubin were found in 40.5, 48.6, 23.1, and 42.9% of the cases, respectively. The most common pathogen in blood and pus cultures was Klebsiella pneumoniae. The mean durations of intravenous antibiotic and total antibiotic use were 29.0 ± 15.7 and 45.1 ± 22.1 days, respectively. Twelve patients (31.6%) were treated with antibiotics alone, while percutaneous needle aspiration, percutaneous pigtail drainage, and surgical intervention were performed in 12 (31.6%), 10 (26.3%), and 5 (13.2%) patients, respectively. No mortality was documented in this series. Conclusion: The present study reflects a relatively declining incidence of liver abscess compared with prior studies in Taiwan. K. pneumoniae remains the most prevalent pathogen in both blood and abscess cultures in Taiwan. Proper antimicrobial therapy with timely drainage generally yielded an adequate treatment response without any mortality.

A comparison of pyogenic liver abscess in patients with or without diabetes: a retrospective study of 246 cases

Background

Pyogenic liver abscess(PLA) has become common in patients with diabetes mellitus (DM), but it is unclear whether differences exist between patients with and without DM. A retrospective study was performed to identify these differences, summarize the clinical experience, and improve the diagnosis and treatment of PLA.

Methods

The patients were enrolled in a teaching hospital from January 2012 to December 2016. The patients were separated into two groups based on comorbidity with diabetes mellitus (DM). The DM group was further separated into two subgroups according to the HbA1C concentration to investigate whether glycaemic control affected the clinical characteristics of PLA patients with DM. Chi-square, Fisher’s exact test, and t-tests were used to analyse and evaluate differences between the two groups.

Results

Two hundred and forty-six PLA patients were identified and 90 (36.6%) had comorbid DM. Patients with DM were older, had higher levels of alkaline phosphatase and γ-glutamyl transferase, hypertension, a loss of body weight, a single abscess, and combined antibiotic therapy with the use of carbapenems and Klebsiella pneumoniae in their blood cultures but a less frequent history of abdominal surgery and Escherichia coli in their pus cultures. When DM patients were compared to non-DM patients, each of these differences was significant (P < 0.05). Diabetic PLA patients with poor glycaemic control had a significantly higher proportion of fever and both lobes abscess(P < 0.05).

Conclusion

PLA patients with diabetes are older, have more serious complications, a higher prevalence of cardiovascular disease, an increased use of combined antibiotic therapy with carbapenem, and K. pneumoniae as the predominant pathogen, but these patients had fewer abdominal surgeries and fewer E. coli infections. In addition, poorly controlled glycaemia in diabetic PLA patients is associated with high incidence of fever and both lobes abscess.

The impact of previous abdominal surgery on clinical characteristics and prognosis of pyogenic liver abscess: A 10-year retrospective study of 392 patients

Many pyogenic liver abscess (PLA) patients underwent abdominal surgery before. However, little is known about the impact of previous abdominal surgery on the clinical characteristics and prognosis of PLA.The clinical data of 392 adult PLA patients who received treatment at our hospital from January 1, 2007 to December 31, 2016 were collected. The demographic data, cause, comorbidities, surgery history, clinical features, laboratory results, imaging findings, microbiological characteristics, choices of treatment, and clinical outcomes were analyzed.In all, 177 PLA patients (45.2%) underwent abdominal surgery before. The median time for the occurrence of PLA after the most recent abdominal surgery was 2.0 (interquartile range 0.25, 6.0) years. PLA patients with a previous abdominal surgery history were more likely to have underlying diseases and presented with more abnormal laboratory values. Klebsiella pneumonia and Escherichia coli were the most common pathogens. Previous abdominal surgery appeared to increase the incidence of E coli. More PLA patients without a previous abdominal surgery history required surgical drainage. However, there were no differences in PLA-related complications, days required for temperature normalization, and length of hospital stay between the 2 groups.Because a large number of PLA patients had a history of abdominal surgery, and proper screening should be performed for patients with any suspicion of a liver abscess after abdominal surgery. Despite the differences in the coexisting conditions, clinical and microbiological characteristics between PLA patients with and without a previous abdominal surgery history, the overall short-term outcomes were comparable.

Periodontitis and dental scaling associated with pyogenic liver abscess: A population-based case-control study

BACKGROUND AND OBJECTIVES

The purpose of this study was to investigate the relationship between periodontitis, dental scaling (DS) and pyogenic liver abscesses (PLAs).

MATERIAL AND METHODS

A nationwide population-based case-control study was applied using data from the National Health Insurance Research Database in Taiwan. We identified and enrolled 691 PLA patients, who were individually matched by age and sex to 2764 controls.

RESULTS

Conditional logistic regression was applied to estimate adjusted odds ratios (aORs) in patients with exposure to periodontitis and DS before PLA. After adjusting for other confounding factors, periodontitis remained a risk factor for PLA among patients aged 20-40 years, with an aOR of 2.31 (95% confidence interval [CI] = 1.37-3.90, P = .0018). In addition, the average aOR for PLA was significantly lower among patients with one DS (aOR = 0.76, 95% CI = 0.59-0.96) and more than one DS (aOR = 0.61, 95% CI = 0.39-0.95) within 1 year before the index date.

CONCLUSION

According to these results, we concluded that adult patients with periodontitis aged <50 years old are more at risk for PLA than controls, particularly when they have no DS. Moreover, from 20 years of age, non-periodontal patients subjected to at least 2 DS per year are less at risk for PLA than controls.

Association between oral corticosteroid use and pyogenic liver abscesses in a case-control study

BACKGROUND AND AIM

There are no epidemiological studies focusing on the association between oral corticosteroid use and pyogenic liver abscesses. The aim of the study was to assess whether oral corticosteroid use is associated with increased odds of pyogenic liver abscesses in adults in Taiwan.

METHODS

This retrospective population-based case-control study was conducted to analyze the database of the Taiwan National Health Insurance Program from 2000 to 2013. Subjects aged 20 to 84 years with their first episode of pyogenic liver abscesses were assigned as the cases (n = 881). Randomly selected subjects without pyogenic liver abscesses aged 20 to 84 years were selected as the controls (n = 3207). A multivariable logistic regression model was used to assess the odds ratio and 95% confidence interval for the correlation of oral corticosteroid use with pyogenic liver abscesses.

RESULTS

After regulating for confounders, the adjusted odds ratio of pyogenic liver abscesses was 1.40 for subjects currently using oral corticosteroids (95% confidence interval 1.14, 1.70), compared with subjects who never used them. Upon further analysis, the adjusted odds ratio of pyogenic liver abscesses was 1.03 for subjects with current use of oral corticosteroids when increasing dosage for every one mg (95% CI 1.01, 1.06).

CONCLUSION

Although the findings are not unexpected, they are important because they suggest that current use of oral corticosteroids is significantly associated with increased odds of developing pyogenic liver abscesses in adults in Taiwan, with a dose-dependent effect.

Population-based cohort study investigating the association between weight loss and pyogenic liver abscesses

BACKGROUND AND AIM

Few systematic studies focus on the association between weight loss and pyogenic liver abscesses. The objective of the study was to assess the association between weight loss and pyogenic liver abscesses in adults in Taiwan.

METHODS

This population-based cohort study utilized the database of the Taiwan National Health Insurance Program. Totally, 8453 subjects aged 20 to 84 years with newly diagnosed weight loss between 2000 and 2012 were assigned as the weight loss group, and 33777 randomly selected subjects without weight loss were assigned as the non-weight loss group. Both the weight loss and the non-weight loss groups were matched according to sex, age, and comorbidities. The incidence of pyogenic liver abscesses at the end of 2013 was measured in both groups.

RESULTS

A multivariable Cox proportional hazards regression model was done and presented evidence that the adjusted HR of pyogenic liver abscess was 2.47 (95 %CI 1.21, 5.02) for those subjects with weight loss and without comorbidities, as compared with those subjects without weight loss and without comorbidities. Among the weight loss group, 5% developed pyogenic liver abscesses within 3 months.

CONCLUSION

Weight loss is associated with pyogenic liver abscesses in adults. Yet weight loss might not be an early clinical symptom of undiagnosed pyogenic liver abscesses.

Predialysis chronic kidney disease correlates with increased risk of pyogenic liver abscess: a population-based cohort study

BACKGROUND/OBJECTIVE

The incidence of pyogenic liver abscess in Taiwan appears to be much higher than that in western countries. However, little is known about the incidence of pyogenic liver abscess among patients with predialysis chronic kidney disease. The objective of this study was to assess the association between predialysis chronic kidney disease and the risk of pyogenic liver abscess in Taiwan.

METHODS

This population-based, retrospective, cohort study was conducted to analyse the database of the Taiwan National Health Insurance Program. There were 81118 subjects aged 20-84 years with newly diagnosed chronic kidney disease as the predialysis chronic kidney disease group since 2000-2010, and 81118 randomly selected subjects without chronic kidney disease as the nonchronic kidney disease group. The predialysis chronic kidney disease group and the nonchronic kidney disease group were matched with sex, age and comorbidities. The incidence of pyogenic liver abscess at the end of 2013 was calculated in both groups. Subjects who currently received dialysis therapy before the endpoint were excluded from the study. The multivariable Cox proportional hazards regression model was used to assess the hazard ratio (HR) and 95% confidence interval (CI) for the risk of pyogenic liver abscess associated with predialysis chronic kidney disease and other comorbidities including alcohol-related disease, biliary stone, chronic liver disease and diabetes mellitus.

RESULTS

The overall incidence of pyogenic liver abscess was 1·65-fold higher in the predialysis chronic kidney disease group than that in the nonchronic kidney disease group (1·38 vs. 0·83 per 1000 person-years, 95% CI 1·59, 1·71). After adjustment for covariables, the adjusted HR of pyogenic liver abscess was 1·51(95% CI 1·30, 1·76) for the predialysis chronic kidney disease group, comparing with the nonchronic kidney disease group. In addition, the adjusted HR would increase to 3·31 (95% CI 2·61, 4·19) for subjects with predialysis chronic kidney disease and with any comorbidity studied.

CONCLUSION

Predialysis chronic kidney disease is associated with 1·5-fold increased risk of pyogenic liver abscess. There seem to be a synergistic effect on the risk of pyogenic liver abscess between predialysis chronic kidney disease and comorbidities.

Population-based cohort study examining the association between splenectomy and empyema in adults in Taiwan

OBJECTIVE

This study aimed to investigate the association between splenectomy and empyema in Taiwan.

METHODS

A population-based cohort study was conducted using the hospitalisation dataset of the Taiwan National Health Insurance Program. A total of 13 193 subjects aged 20-84 years who were newly diagnosed with splenectomy from 2000 to 2010 were enrolled in the splenectomy group and 52 464 randomly selected subjects without splenectomy were enrolled in the non-splenectomy group. Both groups were matched by sex, age, comorbidities and the index year of undergoing splenectomy. The incidence of empyema at the end of 2011 was calculated. A multivariable Cox proportional hazards regression model was used to estimate the HR with 95% CI of empyema associated with splenectomy and other comorbidities.

RESULTS

The overall incidence rate of empyema was 2.56-fold higher in the splenectomy group than in the non-splenectomy group (8.85 vs 3.46 per 1000 person-years). The Kaplan-Meier analysis revealed a higher cumulative incidence of empyema in the splenectomy group than in the non-splenectomy group (6.99% vs 3.37% at the end of follow-up). After adjusting for confounding variables, the adjusted HR of empyema was 2.89 for the splenectomy group compared with that for the non-splenectomy group. Further analysis revealed that HR of empyema was 4.52 for subjects with splenectomy alone.

CONCLUSION

The incidence rate ratio between the splenectomy and non-splenectomy groups reduced from 2.87 in the first 5 years of follow-up to 1.73 in the period following the 5 years. Future studies are required to confirm whether a longer follow-up period would further reduce this average ratio. For the splenectomy group, the overall HR of developing empyema was 2.89 after adjusting for age, sex and comorbidities, which was identified from previous literature. The risk of empyema following splenectomy remains high despite the absence of these comorbidities.

Risk of pneumonia among patients with splenectomy: a retrospective population-based cohort study

BACKGROUND

People without a spleen are particularly susceptible to various overwhelming infections including pneumonia. Although the association between splenectomy and pneumonia has been previously studied, there has been no study using the national claims data.

OBJECTIVES

The aim of the study was to investigate the association between splenectomy and pneumonia.

DESIGN

A retrospective population-based cohort analysis.

SETTINGS

Database of the Taiwan National Health Insurance Program.

PATIENTS

Persons newly diagnosed with splenectomy from 2000 to 2010 were compared with randomly selected subjects without splenectomy. The groups were matched by sex, age, comorbidities, and the year of index date and analyzed by multivariate methods.

MAIN OUTCOME MEASURE

The difference in incidence of pneumonia at the end of 2011.

RESULTS

In 12 757 individuals aged 20-84 years with splenectomy, the overall incidence of pneumonia was 1.86-fold higher than in the 51 019 individuals without splenectomy (25.0 vs. 13.4 per 1000 person-years, 95% CI 1.78, 1.95). After multivariate analysis, the adjusted hazard ratio for pneumonia was 2.2 for subjects with splenectomy (95%CI 2.07, 2.34). In further analysis, in the absence of any comorbidity, the adjusted HR for pneumonia was 3.03 for those with splenectomy alone (95% CI 2.76, 3.33) and 5.28 (95% CI 4.82, 5.78) for splenectomy and any comorbidity.

CONCLUSIONS

Although not a novel finding, we confirmed that splenectomy increases the relative risk for developing pneumonia in a large study population. Even in the absence of any comorbidity, the risk remains high. Patients with splenectomy should receive preventive interventions for pneumonia, such as vaccination.

LIMITATIONS

ICD-9 codes do not differentiate if pneumonia is caused by a viral, a bacterial or unspecified organisms, and some behavioral factors like smoking could not be ascertained directly.

Pneumonia is an independent risk factor for pyogenic liver abscess: A population-based, nested, case-control study

Background

Bacteremic pneumonia is considered a potential cause of distal organ abscess formation. Therefore, we hypothesize that pneumonia is a risk factor for pyogenic liver abscess (PLA).The aim of this study is to explore the association between pneumonia and PLA.

Methodology/Principal findings

A nationwide, population-based, nested, case–control study was conducted using data from the Taiwan National Health Insurance Research Database. In total, 494 patients with PLA and 1,976 propensity score matched controls were enrolled. Conditional logistic regression was used to estimate adjusted odds ratios (aORs) in patients with exposure to pneumonia before PLA. After matched and adjusted for confounding factors including age, sex, urbanization, income, chronic liver disease, alcohol-related disease, biliary stone, chronic kidney disease, diabetes mellitus, chronic liver disease, and cancer, hospitalization for pneumonia remained an independent risk factor for PLA with an aORs of 2.104 [95% confidence interval (CI) = 1.309–3.379, p = 0.0021]. Moreover, the aORs were significantly higher among patients hospitalized for pneumonia within 30 days (aORs = 10.73, 95% CI = 3.381–34.054), 30–90 days (aORs = 4.698, 95% CI = 1.541–14.327) and 90–180 (aORs = 4.000, 95% CI = 1.158–13.817) days before PLA diagnosis.

Conclusion

Pneumonia is an independent risk factor for subsequent PLA. Moreover, hospitalization for pneumonia within 180 days before PLA diagnosis was associated with an increased risk of PLA.

Correlation between proton pump inhibitors and risk of pyogenic liver abscess

BACKGROUND/OBJECTIVE

Little is known about the relationship between proton pump inhibitors use and pyogenic liver abscess. The objective of this study was to evaluate the correlation between proton pump inhibitors use and pyogenic liver abscess in Taiwan.

METHODS

This was a population-based case-control study using the database of the Taiwan National Health Insurance Program since 2000 to 2011. Subjects aged 20 to 84 who experienced their first episode of pyogenic liver abscess were enrolled as the case group (n = 1372). Randomly selected subjects aged 20 to 84 without pyogenic liver abscess were enrolled as the control group (n = 1372). Current use, early use, and late use of proton pump inhibitors was defined as subjects whose last one tablet for proton pump inhibitors was noted ≤30 days, between 31 to 90 days and ≥91 days before the date of admission for pyogenic liver abscess. Subjects who never received a prescription for proton pump inhibitors were defined as nonusers of proton pump inhibitors. A multivariable unconditional logistic regression model was used to measure the odds ratio and 95% confidence interval to evaluate the correlation between proton pump inhibitors use and pyogenic liver abscess.

RESULTS

After adjusting for confounders, the adjusted odds ratio of pyogenic liver abscess was 7.59 for subjects with current use of proton pump inhibitors (95% confidence interval 5.05, 11.4), when compared with nonusers.

CONCLUSIONS

Current use of proton pump inhibitors is associated with a greater risk of pyogenic liver abscess.

Statin Use Correlates with Reduced Risk of Pyogenic Liver Abscess: A Population-Based Case-Control Study

Little research is available on the relationship between statin use and pyogenic liver abscess. The objective of the study was to determine whether prior use of statins is associated with pyogenic liver abscess. This case-control study was conducted to analyse the claim data of the Taiwan National Health Insurance Program. There were 1828 participants aged 20-84 years with first episode of pyogenic liver abscess from 2000 to 2013 as the cases and 1828 randomly selected participants without pyogenic liver abscess matched with sex, age and index year as the controls. Statin use was defined as 'current', 'recent' or 'past' if the statin prescription was filled ≤3 months, 3-6 months or >6 months before the date of pyogenic liver abscess diagnosis, respectively. Relative risk of pyogenic liver abscess associated with statin use was estimated by the odds ratio (OR) with 95% confidence interval (CI) using the multivariable logistic regression model. After controlling for potential confounders, the adjusted ORs of pyogenic liver abscess were 0.65 for participants with current use of statins (95% CI 0.50, 0.84), 0.74 for participants with recent use of statins (95% CI 0.49, 1.11), and 1.10 for participants with past use of statins (95% CI 0.90, 1.34), compared with participants with never use of statins. In the further analysis, the adjusted ORs of pyogenic liver abscess were 0.65 for participants with cumulative duration of statin use ≥12 months (95% CI 0.48, 0.88) and 0.68 for participants with cumulative duration of statin use <12 months (95% CI 0.43, 1.07), compared with participants with never use of statins. Our findings provide strong evidence that patients with current use of statins are associated with a 35% reduced odds of pyogenic liver abscess. The protective effect is stronger for longer duration of statin use.

Association between chronic pancreatitis and pyogenic liver abscess: a nationwide population study

BACKGROUND

The relationship between chronic pancreatitis (CP) and subsequent pyogenic liver abscess (PLA) is not well understood.

METHODS

We investigated the risk of PLA in patients with CP using inpatient claims data from the Taiwan National Health Insurance Program for the period 2000-2010. We identified 17,810 patients with chronic pancreatitis (CP group) and 71,240 patients without CP (non-CP group). Both cohorts were followed until a diagnosis of PLA, until they were censored from the study because of loss to follow-up, death, or termination of insurance, or until the study cut-off date of 31 December 2011. Incidence and risk factors for development of PLA, and the effects of comorbidities, were assessed.

RESULTS

The incidence of PLA in the CP group was 12.9 times that in the non-CP group (38.3 vs. 2.89 events per 1000 person-years; 95% confidence interval [CI], 10.5-15.8). After adjusting for age, sex, and the comorbidities of hypertension, diabetes, hyperlipidemia, cerebral vascular accident, cirrhosis, heart failure, chronic obstructive pulmonary disease, chronic kidney disease, cancer, alcoholism, other diseases of the pancreas, cholecystitis, and cholelithiasis and other disorders of the biliary tract and endoscopic insertion of stent (tube) into the bile duct, the risk of PLA remained higher among CP patients than among the comparison cohort (adjusted hazard ratio, 6.40; 95% CI, 4.83-8.49). CP patients with five or more comorbidities had a significantly higher risk of PLA (adjusted hazard ratio, 24.9; 95% CI, 18.3-33.8).

CONCLUSION

CP was associated with increased risk of subsequent PLA. The risk of PLA was higher in patients with five or more comorbidities.

A case of IgG4-related hepatic inflammatory pseudotumor replaced by an abscess after steroid treatment

BACKGROUND

Hepatic inflammatory pseudotumor (IPT) is a rare disease which often mimics a malignant tumor and is therefore often misdiagnosed and surgically resected. Recently, a concept of IgG4-related diseases (IgG4-RD) has been proposed that is becoming widely recognized and includes IgG4-related hepatic IPT. Corticosteroids are widely accepted as the standard treatment.

CASE PRESENTATION

A 72-year-old Japanese man, who had been followed for ten years after surgery and chemotherapy for treatment of hilar and lower bile duct cancers, developed intermittent fever and abdominal pain and visited this hospital. Blood examinations revealed an inflammatory reaction, worsened glucose intolerance, and an increased level of serum IgG4 (137 mg/dL). Computed tomography (CT) revealed a 5 cm-sized mass in hepatic segment 7. Because of his cancer history, not only was a benign mass suspected, but there was also the possibility of a recurrent biliary malignancy. Liver biopsy was performed and the histology met the criteria for IgG4-related IPT. Corticosteroid therapy was initiated and his symptoms quickly resolved. However, two months later, a repeat CT demonstrated that the hepatic mass had been replaced by an abscess. The abscess was initially refractory, despite tapering corticosteroid treatment, controlling diabetes by intensive insulin therapy, administration of antibiotics, and percutaneous abscess drainage. Finally, after six months, the condition resolved.

CONCLUSION

The diagnosis of hepatic IPT is sometimes difficult. To differentiate it from a malignant tumor, histological examination is necessary. Although corticosteroids are recognized as the standard therapy, unexpected and critical complications can develop in cases of IgG4-related hepatic IPT.

Splenectomy and risk of renal and perinephric abscesses: A population-based cohort study in Taiwan

Little epidemiological research is available on the relationship between splenectomy and renal and perinephric abscesses. The purpose of the study was to examine this issue in Taiwan.We conducted a population-based retrospective cohort study using the hospitalization dataset of the Taiwan National Health Insurance Program. A total of 16,426 participants aged 20 and older who were newly diagnosed with splenectomy from 1998 to 2010 were assigned to the splenectomy group, whereas 65,653 sex-matched, age-matched, and comorbidity-matched, randomly selected participants without splenectomy were assigned to the nonsplenectomy group. The incidence of renal and perinephric abscesses at the end of 2011 was measured in both groups. The multivariable Cox proportional hazards regression model was used to measure the hazard ratio (HR) and 95% confidence interval (CI) for risk of renal and perinephric abscesses associated with splenectomy and other comorbidities including cystic kidney disease, diabetes mellitus, urinary tract infection, and urolithiasis.The overall incidence rate of renal and perinephric abscesses was 2.14-fold greater in the splenectomy group than that in the nonsplenectomy group (2.24 per 10,000 person-years vs 1.05 per 10,000 person-years, 95% CI 2.02, 2.28). After controlling for sex, age, cystic kidney disease, diabetes mellitus, urinary tract infection, and urolithiasis, the multivariable regression analysis demonstrated that the adjusted HR of renal and perinephric abscesses was 2.24 for the splenectomy group (95 % CI 1.30, 3.88), when compared with the nonsplenectomy group. In further analysis, the adjusted HR markedly increased to 7.69 for those comorbid with splenectomy and diabetes mellitus (95% CI 3.31, 17.9).Splenectomy is associated with renal and perinephric abscesses, particularly comorbid with diabetes mellitus. In view of its potential morbidity and mortality, clinicians should consider the possibility of renal and perinephric abscesses when patients with splenectomy present with fever of unknown origin.

The Evolving Nature of Hepatic Abscess: A Review

Hepatic abscess (HA) remains a serious and often difficult to diagnose problem. HAs can be divided into three main categories based on the underlying conditions: infectious, malignant, and iatrogenic. Infectious abscesses include those secondary to direct extension from local infection, systemic bacteremia, and intra-abdominal infections that seed the portal system. However, over the years, the etiologies and risks factors for HA have continued to evolve. Prompt recognition is important for instituting effective management and obtaining good outcomes.

Appendectomy correlates with increased risk of pyogenic liver abscess: A population-based cohort study in Taiwan

Little is known on the association between appendectomy and pyogenic liver abscess. The objective of this study was to investigate the association between appendectomy and the risk of pyogenic liver abscess in Taiwan.This population-based retrospective cohort study was conducted using the hospitalization dataset of the Taiwan National Health Insurance Program. There were 212,530 subjects age 20 to 84 years with newly diagnosed appendectomy as the appendectomy group since 1998 to 2010, and 850,099 randomly selected subjects without appendectomy as the nonappendectomy group. Both appendectomy and nonappendectomy groups were matched with sex, age, comorbidities, and index year of diagnosing appendectomy. The incidence of pyogenic liver abscess at the end of 2011 was estimated in both groups. The multivariable Cox proportional hazards regression model was applied to investigate the hazard ratio (HR) and 95% confidence interval (CI) for risk of pyogenic liver abscess associated with appendectomy and other comorbidities including alcoholism, biliary stone, chronic kidney disease, chronic liver diseases, and diabetes mellitus.The overall incidence of pyogenic liver abscess was 1.73-fold greater in the appendectomy group than that in the nonappendectomy group (3.85 vs 2.22 per 10,000 person-years, 95% CI 1.71, 1.76). The multivariable regression analysis disclosed that the adjusted HR of pyogenic liver abscess was 1.77 for the appendectomy group (95% CI 1.59, 1.97), when compared with the nonappendectomy group.Appendectomy is associated with increased hazard of pyogenic liver abscess. Further studies remain necessary to confirm our findings.

Splenectomy Correlates With Increased Risk of Acute Pancreatitis: A Case-Control Study in Taiwan

OBJECTIVE

The objective of the study was to investigate the association between splenectomy and acute pancreatitis.

METHODS

We conducted a case-control study using the database of the Taiwan National Health Insurance Program. We included 7666 subjects aged 20-84 years with first-time acute pancreatitis during the period of 1998-2011 as cases and 30 664 randomly selected subjects without acute pancreatitis as controls. Both cases and controls were matched for sex, age, and index year of acute pancreatitis diagnosis. The association of acute pancreatitis with splenectomy was examined using a multivariable unconditional logistic regression model and reported as an odds ratio and its 95% confidence interval (CI).

RESULTS

After adjustment for covariables, the adjusted odds ratio of acute pancreatitis was 2.90 for subjects with splenectomy (95% CI, 1.39-6.05) compared with subjects without splenectomy.

CONCLUSIONS

Splenectomy is associated with acute pancreatitis. Further studies are necessary to clarify the underlying mechanism.