Transient splenomegaly in acute pancreatitis

Development and validation of a nomogram based on Lasso-Logistic regression for predicting splenomegaly secondary to acute pancreatitis

PURPOSE

Investigate the clinical characteristics of splenomegaly secondary to acute pancreatitis (SSAP) and construct a nomogram prediction model based on Lasso-Logistic regression.

METHODS

A retrospective case-control study was conducted to analyze the laboratory parameters and computed tomography (CT) imaging of acute pancreatitis (AP) patients recruited at Xuanwu Hospital from December 2014 to December 2021. Lasso regression was used to identify risk factors, and a novel nomogram was developed. The performance of the nomogram in discrimination, calibration, and clinical usefulness was evaluated through internal validation.

RESULTS

The prevalence of SSAP was 9.2% (88/950), with the first detection occurring 65(30, 125) days after AP onset. Compared with the control group, the SSAP group exhibited a higher frequency of persistent respiratory failure, persistent renal failure, infected pancreatic necrosis, and severe AP, along with an increased need for surgery and longer hospital stay (P < 0.05 for all). There were 185 and 79 patients in the training and internal validation cohorts, respectively. Variables screened by Lasso regression, including platelet count, white blood cell (WBC) count, local complications, and modified CT severity index (mCTSI), were incorporated into the Logistic model. Multivariate analysis showed that WBC count ≦9.71 × 109/L, platelet count ≦140 × 109/L, mCTSI ≧8, and the presence of local complications were independently associated with the occurrence of SSAP. The area under the receiver operating characteristic curve was 0.790. The Hosmer-Lemeshow test showed that the model had good fitness (P = 0.954). Additionally, the nomogram performed well in the internal validation cohorts.

CONCLUSIONS

SSAP is relatively common, and patients with this condition often have a worse clinical prognosis. Patients with low WBC and platelet counts, high mCTSI, and local complications in the early stages of the illness are at a higher risk for SSAP. A simple nomogram tool can be helpful for early prediction of SSAP.

The risk of developing splanchnic vein thrombosis in acute pancreatitis increases 3 days after symptom onset: A systematic review and meta-analysis

BACKGROUND

Splanchnic vein thrombosis is a complication of acute pancreatitis (AP) and is likely often underdiagnosed.

OBJECTIVES

We aimed to understand the time course and risk factors of splanchnic vein thrombosis in the early phase of AP.

METHODS

A systematic search was conducted using the PRISMA guidelines (PROSPERO registration CRD42022367578). Inclusion criteria were appropriate imaging techniques in adult AP patients, studies that reported splanchnic vein thrombosis data from the early phase, and reliable information on the timing of imaging in relation to the onset of pancreatitis symptoms or hospital admission. The proportion of patients with thrombosis with 95% confidence intervals (CI) was calculated using random-effects meta-analyses, and multiple subgroup analyses were performed.

RESULTS

Data from 1951 patients from 14 studies were analyzed. The proportion of patients with splanchnic vein thrombosis within 12 days after symptom onset was 0.13 (CI 0.07-0.23). The occurrence was lowest at 0.06 (CI 0.03-0.1) between 0 and 3 days after symptom onset, and increased fourfold to 0.23 (CI 0.16-0.31) between 3 and 11 days. On hospital admission, the proportion of patients affected was 0.12 (CI 0.02-0.49); it was 0.17 (CI 0.03-0.58) 1-5 days after admission. The prevalence in mild, moderate, and severe AP was 0.15 (CI 0.05-0.36), 0.26 (CI 0.15-0.43), and 0.27 (CI 0.17-0.4), respectively. Alcoholic etiology (0.31, CI 0.13-0.58) and pancreatic necrosis (0.55, CI 0.29-0.78, necrosis above 30%) correlated with increased SVT prevalence.

CONCLUSION

The risk of developing splanchnic vein thrombosis is significant in the early stages of AP and may affect up to a quarter of patients. Alcoholic etiology, pancreatic necrosis, and severity may increase the prevalence of splanchnic vein thrombosis.

Incidence and prognostic role of pleural effusion in patients with acute pancreatitis: a meta-analysis

BACKGROUND

Pleural effusion (PE) is reported as a common complication in acute pancreatitis (AP), while the incidence of PE in AP varies widely among studies, and the association between PE and mortality is not clear. This study aimed to comprehensively analyze the pooled incidence of PE in patients with AP and to evaluate the influence of PE on mortality through a meta-analysis.

METHOD

Six databases (PubMed, Web of Science, EMBASE, Cochrane, Scopus, and OVID) were searched thoroughly for relevant studies. Data were extracted, and Stata SE 16.0 software was applied to compute the pooled incidence of PE and assess the association between PE and mortality, taking the risk ratio (RR) as the effect size.

RESULTS

Thirty-five articles involving 7,675 patients with AP were eventually included in this meta-analysis. The pooled incidence of PE was 34% (95% CI: 28%-39%), with significant heterogeneity among studies (I2=96.7%). Further analysis revealed that the pooled incidence of unilateral and small PE occupied 49% (95% CI: 21%-77%) and 59% (95% CI: 38%-81%) of AP patients complicated by PE, respectively. The subgroup analysis revealed that "region" and "examination method" may contribute to heterogeneity. PE may be associated with increased mortality in AP patients (RR 3.99, 95% CI: 1.73-9.2).

CONCLUSION

This study suggested that PE is a common complication with high pooled incidence and that PE may be associated with increased mortality in AP patients. More studies should be performed to validate our findings.

Spleen and splenic vascular involvement in acute pancreatitis: an MRI study

Background

To investigate the spleen and splenic vascular involvement in acute pancreatitis (AP) and their correlations with the severity of AP using magnetic resonance imaging (MRI).

Methods

MRI of 239 patients with AP was retrospectively reviewed to assess splenic and splenic vascular complications, and the severity of AP. The severity of AP was graded by the MRI severity index (MRSI) and the New Revised Classification of AP 2012. The intravoxel incoherent motion (IVIM) parameters (D, D*, and f) of spleen were measured. Thirty-five subjects without pancreatic and splenic disorders were enrolled as controls for IVIM parameters.

Results

Among the 239 patients with AP, splenomegaly (16.7%), splenic infarction (0.4%), splenic vein thrombosis (4.2%), phlebitis (7.5%) and arteritis (4.2%) were observed. Splenic vascular involvement was positively correlated with the severity of AP based on both the MRSI and the New Revised Classification of AP 2012 (P<0.05). In the control and AP groups, the splenic f values were (0.164±0.074) vs. (0.210±0.095) (P=0.023) respectively. In AP patients with and without splenomegaly, f = (0.240±0.091) vs. (0.203±0.095) (P<0.001).

Conclusions

Splenic vascular involvement and splenomegaly were common in AP. The vascular involvement was associated with the severity of AP. This complication should be considered when severity and prognosis of AP are assessed. Quantitative analysis of the spleen with IVIM might be a useful imaging biomarker for splenic perfusion changes in AP, especially in those with splenomegaly.

An immune-modulating formula comprising whey peptides and fermented milk improves inflammation-related remote organ injuries in diet-induced acute pancreatitis in mice

It has been demonstrated that an immune-modulating enteral formula enriched with whey peptides and fermented milk (IMF) had anti-inflammatory effects in some experimental models when it was administered before the induction of inflammation. Here, we investigated the anti-inflammatory effects of the IMF administration after the onset of systemic inflammation and investigated whether the IMF could improve the remote organ injuries in an acute pancreatitis (AP) model. Mice were fasted for 12 hours and then fed a choline-deficient and ethionine-supplemented diet (CDE diet) for 24 hours to induce pancreatitis. In experiment 1, the diet was replaced with a control enteral formula, and mice were sacrificed at 24-hour intervals for 96 hours. In experiment 2, mice were randomized into control and IMF groups and received the control formula or the IMF respectively for 72 hr or 96 hr. In experiment 1, pancreatitis was induced by the CDE diet, and inflammatory mediators were elevated for several days. Remote organ injuries such as splenomegaly, hepatomegaly, and elevation of the hepatic enzymes developed. A significant strong positive correlation was observed between plasma MCP-1 and hepatic enzymes. In experiment 2, the IMF significantly improved splenomegaly, hepatomegaly, and the elevation of hepatic enzymes. Plasma MCP-1 levels were significantly lower in the IMF group than in the control group. Nutrition management with the IMF may be useful for alleviating remote organ injuries after AP.

Prevalence of Splanchnic Vein Thrombosis in Pancreatitis: A Systematic Review and Meta-Analysis of Observational Studies

Splanchnic vein thrombosis (SVT) may be negatively associated with the prognosis of pancreatitis. We performed a systematic review and meta-analysis of literatures to explore the prevalence of SVT in pancreatitis. All observational studies regarding the prevalence of SVT in pancreatitis were identified via PubMed and EMBASE databases. The prevalence of SVT was pooled in the total of patients with pancreatitis. And it was also pooled in the subgroup analyses according to the stage and causes of pancreatitis, location of SVT, and regions where the studies were performed. After the review of 714 studies, 44 studies fulfilled the inclusion criteria. Meta-analyses showed a pooled prevalence of SVT of 13.6% in pancreatitis. According to the stage of pancreatitis, the pooled prevalence of SVT was 16.6% and 11.6% in patients with acute and chronic pancreatitis, respectively. According to the causes of pancreatitis, the pooled prevalence of SVT was 12.2% and 14.6% in patients with hereditary and autoimmune pancreatitis. According to the location of SVT, the pooled prevalence of portal vein, splenic vein, and mesenteric vein thrombosis was 6.2%, 11.2%, and 2.7% in pancreatitis. The prevalence of SVT in pancreatitis was 16.9%, 11.5%, and 8.5% in Europe, America, and Asia, respectively.

Natural history of pancreatitis-induced splenic vein thrombosis: a systematic review and meta-analysis of its incidence and rate of gastrointestinal bleeding

BACKGROUND

Pancreatitis-induced splenic vein thrombosis (PISVT) is an acquired anatomic abnormality that impacts decision making in pancreatic surgery. Despite this influence, its incidence and the rate of associated gastrointestinal (GI) bleeding are imprecisely known.

METHODS

The MEDLINE, EMBASE, Cochrane Central Register of Clinical Trials and Cochrane Database of Systematic Reviews databases were searched from their inception to June 2010 for abstracts documenting PISVT in acute (AP) or chronic pancreatitis (CP). Two reviewers independently graded abstracts for inclusion in this review. Heterogeneity in combining data was assumed prior to pooling. Random-effects meta-analyses were performed to estimate percentages and 95% confidence intervals.

RESULTS

After review of 241 abstracts, 47 studies and 52 case reports were graded as relevant. These represent a cohort of 805 patients with PISVT reported in the literature. A meta-analysis of studies meeting inclusion criteria shows mean incidences of PISVT of 14.1% in all patients, 22.6% in patients with AP and 12.4% in patients with CP. The incidence of associated splenomegaly was only 51.9% in these patients. Varices were identified in 53.0% of patients and were gastric in 77.3% of cases. The overall rate of GI bleeding was 12.3%.

CONCLUSIONS

Although reported incidences of PISVT vary widely across studies, an overall incidence of 14.1% is reported. Splenomegaly is an unreliable sign of PISVT. Although the true natural history of PISVT remains unknown, the collective reported rate of associated GI bleeding is 12.3%.

Splenic atrophy in experimental severe acute pancreatitis

INTRODUCTION

In severe acute pancreatitis, immunologic impairment is supposed to be linked to the development of subsequent infectious complications.

AIM

To examine alterations of spleen in rat experimental severe acute pancreatitis.

METHODOLOGY

Severe necrotizing pancreatitis was induced by retrograde injection of 3% sodium deoxycholate into the biliopancreatic ducts of male Wistar rats.

RESULTS

In the rats with pancreatitis 12 and 24 hours after the induction, splenic weights were significantly lower than those of sham-operated rats. Numbers of splenocytes were also significantly reduced simultaneously. By in situ nick-end labeling, DNA fragmentation enzyme linked immunosorbent assay (ELISA), and DNA electrophoresis, no apoptosis was detected on the splenocytes from the rats with pancreatitis 6, 12, and 24 hours after the onset. Peripheral lymphocytes in the rats with pancreatitis were significantly decreased 6, 12, and 24 hours after the onset compared with those in sham-operated rats. With antecedent splenectomy, peripheral lymphocyte counts 12 hours after the onset were significantly lower than those in rats who had not undergone splenectomy. Moreover, nuclear fragmentation was noted, and DNA fragments were significantly increased in peripheral lymphocytes at 6 hours in sodium deoxycholate pancreatitis.

CONCLUSION

These results indicate that splenic atrophy resulting from splenocyte reduction occurs in rat experimental severe acute pancreatitis. It is suggested that splenocytes are recruited into systemic circulation in response to peripheral lymphocyte reduction as a result of apoptosis.