Quantitative evaluation of pancreatic tumor fibrosis using shear wave elastography

Background & aimsThere is no established non-invasive method for diagnosis of pancreatic fibrosis. Shear wave elastography (SW-EG) may be a candidate for this purpose. The aims of this study were to assess the reproducibility of SW-EG in the normal imaging pancreas (Phase 1) and to evaluate the diagnostic performance of SW-EG for pancreatic fibrosis classified histologically (Phase 2).MethodsPhase 1: This included 127 cases that underwent SW-EG of the normal imaging pancreas. SW-EG was measured at least five times in the pancreatic parenchyma and the median of repeated measurements was defined as the pancreatic elastic modulus (PEM). Phase 2: This included 53 cases that underwent SW-EG of the pancreatic parenchyma preoperatively and in which pancreas parenchyma were evaluated histologically. Histological fibrosis was graded in 4 stages: normal, mild, moderate, and severe.ResultsPhase 1: Median PEM in the head, body, and tail of the pancreas were 3.23, 3.17, and 2.91 kPa, respectively, with no significant difference among regions (P = 0.554). The intraclass correlation coefficient showed good reproducibility (ρ = 0.71) after 5 measurements. Phase 2: There was a significant positive correlation between PEM and the histological pancreatic fibrosis stage (r_s = 0.63, P < 0.001). Areas under the receiver operating characteristic curve for the accuracy of SW-EG for diagnosis of pancreatic fibrosis were 0.85 (≥mild), 0.84 (≥moderate), and 0.87 (severe).ConclusionSW-EG can be used to determine the stage of pancreatic fibrosis non-invasively with high accuracy and reproducibility.     

Noninvasive assessment of liver fibrosis in children with chronic hepatitis C: Shear wave elastography and APRI versus liver biopsy

Background and study aimsHepatitis C virus (HCV) is a major cause of chronic hepatitis. Although liver histopathological examination remains the reference standard for liver fibrosis assessment, noninvasive means of assessment such as shear wave elastography (SWE) and aspartate aminotransferase–platelet ratio index (APRI) have been developed to reduce the need for biopsy. We evaluated the efficacy of SWE and APRI versus liver biopsy for liver fibrosis assessment in children with chronic HCV infection.Patients and methodsFibrosis staging was performed in 46 children (35 boys, 11 girls; mean age: 15.52 ± 2.71 years) with liver biopsy-proven chronic HCV infection according to the METAVIR system. SWE was performed within 6 months of liver biopsy. APRI scores were calculated using data collected on the day of biopsy.ResultsEighteen children had no or mild fibrosis (<F2, 39.1%) and 28 had significant fibrosis (≥F2, 60.9%), with a significant difference between the corresponding mean APRI scores (0.43 ± 0.23 vs 1.26 ± 1.24; p = 0.043). The APRI scores exhibited a significant correlation with the METAVIR stage (r = 0.630; p < 0.001). The SWE values were significantly higher in those with significant fibrosis than in those with no or mild fibrosis (10.43 vs 4.26 kPa; p < 0.000). These values exhibited significant correlations with the METAVIR stage and APRI score (r = 0.863 and 0.544, respectively; both p < 0.001). For differentiating significant fibrosis, the sensitivity, specificity and positive and negative predictive values for an APRI cutoff value of 0.62 were 46.43%, 94.4%, 92.9% and 53.1%, respectively, and these values for an SWE cutoff value of 7.6 kPa were 55.88%, 100%, 100% and 44.4%, respectively.ConclusionIn the clinical assessment of children, the APRI score and SWE can help differentiate between no or mild fibrosis and significant fibrosis. The routine use of SWE and APRI may help decrease the number of liver biopsies performed.     

Value of shear wave elastography with maximal elasticity in differentiating benign and malignant solid focal liver lesions

BACKGROUNDIt is important to differentiate benign and malignant focal liver lesions (FLLs) accurately. Despite the wide use and acceptance of shear wave elastography (SWE), its value for assessing the elasticity of FLLs and differentiating benign and malignant FLLs is still investigational. Previous studies of SWE for FLLs used mean elasticity as the parameter to reflect the stiffness of FLLs. Considering the inhomogeneity of tumor stiffness, maximal elasticity (Emax) might be the suitable parameter to reflect the stiffness of FLLs and to differentiate malignant FLLs from benign ones.AIMTo explore the value of SWE with Emax in differential diagnosis of solid FLLs.METHODSWe included 104 solid FLLs in 95 patients and 50 healthy volunteers. All the subjects were examined using conventional ultrasound (US) and virtual touch tissue quantification(VTQ) imaging. A diagnosis of benign or malignant FLL was made using conventional US. Ten VTQ values were acquired after 10 consecutive measurements for each FLL and each normal liver, and the largest value was recorded as Emax.RESULTSThere were 56 cases of malignant FLLs and 48 cases of benign FLLs in this study. Emax of malignant FLLs (3.29 ± 0.88 m/s) was significantly higher than that of benign FLLs (1.30 ± 0.46 m/s, P < 0.01) and that of livers in healthy volunteers (1.15 ± 0.17 m/s, P < 0.01). The cut-off point of Emax was 1.945, and the area under the curve was 0.978. The sensitivity and specificity of Emax were 92.9% and 91.7%, respectively, higher (but not significantly) than those of conventional US (80.4% for sensitivity and 81.3% for specificity). Combined diagnosis of conventional US and Emax using parallel testing improved the sensitivity to 100% with specificity of 75%.CONCLUSIONSWE is a convenient and easy method to obtain accurate stiffness information of solid FLLs. Emax is useful for differential diagnosis of FLLs, especially in combination with conventional US.     

Study of detection times for liver stiffness evaluation by shear wave elastography

AIM: To investigate enough valid measurements (VMs) to assess liver fibrosis in chronic hepatitis B patients (CHB).METHODS: One hundred and twelve CHB patients (25 women, 87 men) with a mean age of 38.43 years received liver stiffness evaluations using real-time shear wave elastography for 10 VMs. All patients underwent liver biopsy. Based on the biopsy pathology, the liver stiffness data obtained from different VMs (1, 2, 3, 5 and 10 times) were compared for the evaluation of liver fibrosis. The correlation between the elastic modulus means of the liver obtained from different VMs of detection at each pathological stage was analysed. The receiver operating characteristic (ROC) curve was employed to determine the diagnostic performance of different VMs of detection, and the areas under the ROC curve of different groups were compared.RESULTS: The liver stiffness values obtained from 1 VM, 2 VMs, 3 VMs, 5 VMs and all 10 VMs for stage F0 were 6.95 ± 2.01 kPa, 6.87 ± 1.83 kPa, 6.90 ± 1.88 kPa, 6.95 ± 1.93 kPa and 7.15 ± 1.89 kPa, respectively (F = 0.043, P = 0.996). For stage F1, these values were 7.12 ± 1.72 kPa, 7.24 ± 1.72 kPa, 7.21 ± 1.74 kPa, 7.10 ± 1.78 kPa and 7.04 ± 1.70 kPa, respectively (F = 0.075, P = 0.990). For stage F2, they were 9.37 ± 3.87 kPa, 9.18 ± 3.68 kPa, 9.19 ± 3.81 kPa, 9.18 ± 3.81 kPa and 9.19 ± 3.53 kPa, respectively (F = 0.012, P = 1.000). For stage F3, these were 11.91 ± 3.88 kPa, 11.78 ± 4.04 kPa, 11.83 ± 4.07 kPa, 11.94 ± 4.17 kPa and 12.00 ± 4.02 kPa, respectively (F = 0.010, P = 1.000). For stage F4, the readings were 19.30 ± 7.63 kPa, 19.40 ± 7.36 kPa, 19.54 ± 7.43 kPa, 19.73 ± 7.21 kPa and 20.25 ± 7.22 kPa, respectively (F = 0.054, P = 0.995). There were no significant differences between these groups. Intraclass correlation coefficients among different pathological stages (F0-F4) with different detection VMs were 0.995, 0.993, 0.996, 0.994 and 0.996, respectively. The mean elasticity values from 1 VM, 2 VMs, 3 VMs, 5 VMs and 10 VMs can accurately distinguish fibrosis stages (F0 vs F1234, F01 vs F234, F012 vs F34 and F0123 vs F4) with no significant differences in the five groups (P > 0.05 for all).CONCLUSION: One VM may be sufficient to assess liver fibrosis by using SWE without any significant loss of accuracy in patients with CHB. However, future studies of larger patient samples are necessary for the validation of this method.     

Prediction of pancreatic fistula after pancreatectomy by virtual touch tissue imaging and quantification (VTIQ) technology

ObjectivesThe aim of this study was to quantitatively evaluate the stiffness of pancreatic parenchyma and solid focal pancreatic lesions (FPLs) by virtual touch tissue imaging and quantification (VTIQ) technique and to investigate the potential usefulness of VTIQ method in the prediction of post-operative pancreatic fistula (POPF) after pancreatectomy.MethodsIn this prospective study, patients who scheduled to undergo pancreatectomy were initially enrolled and received VTIQ assessment within one week before surgery. VTIQ elastography (Siemens ACUSON Sequoia, 5C-1 transducer) was used to measure the shear wave velocity (SWV) value of FPLs and the body part pancreatic parenchyma. The palpation stiffness of pancreas was qualitatively evaluated during operation by surgeons. POPF was finally diagnosed and graded through a three-weeks post-operative follow-up according to international study group of pancreatic fistula (ISGPF). SWV values were compared between POPF positive and negative group. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic efficacy of SWV value in predicting POPF.ResultsFrom December 2020 to June 2021, 44 patients were finally enrolled in this study, among which, 26 patients were identified to develop POPF after pancreatectomy. The SWV value of pancreatic parenchyma in POPF positive group was significantly lower than that in POPF negative group (P = 0.001). However, there was no significant difference in palpation stiffness between the two groups (P = 0.124). Besides, neither the SWV value of FPL nor the SWV ratio between FPL to surrounding pancreatic parenchyma differ significantly between POPF positive and negative group (P > 0.05). Taking SWV value of pancreatic parenchyma >1.10 m/s as a cut-off value for predicting POPF, area under the receiver operating characteristic curve (AUROC) was 0.864 with 72.2% sensitivity, 92.3% specificity, 86.7% positive predictive value (PPV) and 82.8% negative predictive value (NPV), respectively.ConclusionsVTIQ technique might be a potential non-invasive imaging method to predict POPF before pancreatectomy in future clinical practice.     

Value of shear wave elastography combined with the Toronto clinical scoring system in diagnosis of diabetic peripheral neuropathy

To evaluate the diagnostic values of shear wave elastography (SWE) alone and in combination with the Toronto clinical scoring system (TCSS) on diabetic peripheral neuropathy (DPN) in patients with type 2 diabetes mellitus (T2DM).The study included 41 DPN patients, 42 non-DPN patients, and 21 healthy volunteers. Conventional ultrasonography and SWE were performed on the 2 sides of the tibial nerves, and cross-sectional area (CSA) and nerve stiffness were measured. TCSS was applied to all patients. A receiver operating characteristic curve analysis was performed.The stiffness of the tibial nerve, as measured as mean, minimum or maximum elasticity, was significantly higher in patients in the DPN group than the other groups (P < .05). The tibial nerve of subjects in the non-DPN group was significantly stiffer compared to the control group (P < .05). There was no significant difference of the tibial nerve CSA among the 3 groups (P > .05). Mean elasticity of the tibial nerve with a cutoff of 71.3 kPa was the most sensitive (68.3%) and had a higher area under the curve (0.712; 0.602–0.806) among the 3 shear elasticity indices for diagnosing DPN when used alone. When combining SWE with TCSS in diagnosing DPN, the most effective parameter was the EMax, which yielded a sensitivity of 100.00% and a specificity of 95.24%.SWE is a better diagnostic tool for DPN than the conventional ultrasonic parameter CSA, and a higher diagnostic value is attained when combining SWE with TCSS.     

Comparison of five-phase computed tomography images of type 1 autoimmune pancreatitis and pancreatic cancer: Emphasis on cases with atypical images

Background/objectivesInternational consensus diagnostic criteria (ICDC) include characteristic images of autoimmune pancreatitis (AIP); however, reports on atypical cases are increasing. The aims of this study were to compare CT findings between AIP and pancreatic cancer (PC), and to analyze type 1 AIPs showing atypical images.MethodsFive-phase CT images were compared between 80 type 1-AIP lesions and 80 size- and location-matched PCs in the case-control study. Atypical AIPs were diagnosed based on the four ICDC items.ResultsICDC items were recognized in most AIP lesions; pancreatic enlargement (87.7%), narrowing of the main pancreatic duct (98.8%), delayed enhancement (100%), and no marked upstream-duct dilation (97.5%). CT values of AIPs increased rapidly until the pancreatic phase and decreased afterward, while those of PCs gradually increased until the delayed phase (P < 0.0001). Atypical images were recognized in 14.8% of AIPs, commonly without pancreatic enlargement (18.5 mm) and sometimes mimicking intraductal neoplasms. The CT values and their ratios were different between atypical AIPs and size-matched PCs most significantly in the pancreatic phase, but similar in the delayed phase.ConclusionsOrdinary type 1 AIPs can be diagnosed with the ICDC, but atypical AIPs represented a small fraction. “Delayed enhancement” is characteristic to ordinary AIPs, however, “pancreatic-phase enhancement” is more diagnostic for atypical AIPs.     

Does tobacco influence the natural history of autoimmune pancreatitis?

Tobacco recently appeared as a major independent factor adversely influencing the natural course of alcoholic chronic pancreatitis. However, the role of tobacco in patients with autoimmune pancreatitis (AIP) has never been studied. Type 2 AIP is associated with inflammatory bowel disease, especially ulcerative colitis in which smoking is protective. The aim of our study was to evaluate the influence of smoking on course of AIP.Patients and methodsAll consecutive patients followed in our centre for AIP according to ICDC were studied. Tobacco consumption was recorded. A relation between smoking and all event related to AIP was searched for.Results96 patients with type 1 (73%) or type 2 (27%) AIP were included; 76% of patients were low smokers (never, ex- or smokers <10 p.y.) and 24% were high smokers (≥10 p.y.). The mean follow-up was 60 months [5–188]. AIP relapse was observed in 26% of patients. At the end-point, smokers ≥10 p.y. presented more frequently diabetes (50% vs 27%, p = 0.04) and imaging pancreatic damages (59% vs 34%, p = 0.02) than low smokers. There was also a non significant tendency to observe more frequently exocrine insufficiency and relapse in smokers ≥10 pack-year. No protective effect of smoking was observed in the subgroup of patients with type 2 AIP and ulcerative colitis.ConclusionsIn patients with AIP, high tobacco intake is associated with the risk of imaging pancreatic damages and with the occurrence of diabetes. Smoking cessation should be recommended.     

剪切波弹性成像技术联合多参数评估肝硬化患者食管静脉曲张价值研究*

目的 探讨应用剪切波弹性成像(SWE)技术联合多参数评估肝硬化患者并发食管静脉曲张(EV)的价值。方法 2018年3月～2021年3月我院收治的肝硬化患者89例,接受胃镜检查,了解EV发生情况,采用SWE技术检测脾脏杨氏模量最大值(Emax)和杨氏模量平均值(Emean),使用彩色多普勒超声检测肝脏门静脉直径(PVD)、脾脏厚径(ST)、脾脏长径(SD)和脾静脉直径(SVD),应用受试者工作特征曲线下面积(AUC)分析各参数诊断肝硬化患者并发EV的效能。结果 经胃镜检查发现,本组89例肝硬化患者并发EV者53例;EV组在Child-Pugh分级、白蛋白、凝血酶原时间国际标准化比值、血小板计数和有腹水的比率等方面与非EV组比,均存在显著性差异(P<0.05);EV组Emax和Emean分别为(55.9±10.5)kPa和(38.9±9.2)kPa,显著大于非EV组【分别为(45.2±7.3)kPa和(29.3±6.7)kPa,P<0.05】,PVD、ST、SD和SVD分别为(13.6±2.1)mm、(48.0±9.4)mm、(149.1±27.1)mm和(10.1±1.9)mm,均显著大于非EV组【分别为(11.5±1.8)mm、(36.9±8.7)mm、(119.8±24.9)mm和(7.8±1.7)mm,P<0.05】;分别以Emax、Emean、PVD、ST、SD和SVD为53.2 kPa、33.6 kPa、11.9 mm、43.8 mm、136.5 mm和8.9 mm为截断点,其诊断肝硬化并发EV的AUC分别为0.84、0.83、0.73、0.80、0.67和0.82,诊断的敏感度和特异度分别为66.0%和88.9%、75.5%和77.8%、79.3%和61.1%、77.4%和72.2%、58.5%和69.4%、77.4%和80.6%。结论 应用SWE技术测量脾脏Emax和Emean可用于肝硬化患者并发EV的诊断,对帮助判断病情,及时予以预防处理。     

The relationship between pancreatic atrophy after steroid therapy and diabetes mellitus in patients with autoimmune pancreatitis

Background/objectivesMany patients with autoimmune pancreatitis (AIP) have an association with diabetes mellitus. It has not been clarified whether steroid therapy for AIP improves or worsens the condition of diabetes mellitus. The aim of this study was thus to investigate the relationship between pancreatic atrophy after steroid therapy and the clinical course of diabetes.MethodsThirty-one AIP patients, who were treated by steroid therapy, were included in this study during December 2005 to March 2013. Pancreatic atrophy 6 months after the beginning of steroid therapy was defined to be present when the width of the pancreatic body was less than 10 mm. The relationships between pancreatic atrophy and patient characteristics as well as the course of diabetes were examined.ResultsSteroid therapy was effective in all treated patients. Pancreatic atrophy was observed in 12 patients and not in 19 patients after the steroid therapy. AIP patients with pancreatic atrophy showed higher incidences of diabetes mellitus (p = 0.001, 9/12 vs. 2/19), diabetes control worsening (p = 0.007, 7/12 vs. 2/17), and new onset of diabetes (p = 0.02, 5/7 vs. 1/18) than those without atrophy. It was not associated with gender, other organ involvement, pattern of pancreas swelling (diffuse/focal), serum IgG4 level, alcohol intake, and pancreatic calcification on CT. Patients with new onset of diabetes needed insulin therapy, even in the maintenance therapy of AIP.ConclusionsAIP patients with pancreatic atrophy after steroid therapy have a high incidence of diabetes mellitus. New onset of diabetes is closely associated with pancreatic atrophy after steroid therapy.     

直肠腔内剪切波弹性成像对局部进展期直肠癌新辅助放化疗后T分期的价值

目的探讨经直肠腔内超声弹性成像对局部进展期直肠癌新辅助放化疗后T分期的应用价值。 方法收集就诊于中国医学科学院肿瘤医院的局部进展期直肠癌患者57例,均于术前接受新辅助放化疗,并进行根治性手术。所有患者新辅助放化疗前后行经直肠腔内超声（ERUS）及剪切波弹性成像（SWE）检查。以术后病理为金标准,评价ERUS及SWE对直肠癌新辅助放化疗后T分期的准确性。 结果ERUS对局部进展期直肠癌新辅助放化疗后T分期的诊断准确率为59.6%（34/57）。ERUS判断肿瘤局限于肠壁（T0~T2）的准确性为39.3%（11/28）。46.2%（6/13）的ypT0期患者被过高分期。放化疗前后,杨氏模量最大值（Emax）平均值分别为（103.27±29.23）kPa、（49.91±32.67）kPa,差异有统计学意义（t=6.236,P<0.001）。新辅助治疗后病理T分期越高,Emax平均值随之升高。以放化疗后病灶Emax构建ROC曲线,选取58 kPa作为最佳诊断临界点时,诊断放化疗后残余病变局限于肠壁内的敏感性、特异性、准确性分别为76.2%、86.4%、78.9%;以43 kPa为最佳诊断临界点,诊断ypT0期的敏感性、特异性、准确性分别为100%、84.6%、89.7%,均较ERUS有改善,说明SWE可提高新辅助治疗后直肠癌再分期的准确性,有助于临床治疗方案的制定。 结论经直肠腔内SWE可提高局部进展期直肠癌新辅助放化疗后T分期的准确性,可丰富现有影像检查方法。     

Evaluation of spleen stiffness in healthy volunteers using point shear wave elastography

Introduction and ObjectivesThis study aims to measure the values of spleen stiffness (SS) in healthy subjects, the inter-operator agreement in SS measurement, and to detect statistically significant correlations between SS and age, sex, weight, BMI, portal vein dynamics and splenic dimensions.Materials and methodsThe study included 100 healthy volunteers who had no substantial alcohol intake (<30 g/daily for man, <20 g/daily women), were negative on hepatitis B, hepatitis C, HIV blood serology, and had any history of lymphoproliferative disorders. Abdominal ultrasound, liver and spleen elastography were performed on each patient to search for focal splenic lesions, bile tract or portal vein dilatation, moderate/severe liver steatosis, and to measure liver and spleen stiffness.ResultsThe mean value was 18.14 (±3.08) kPa. In the group of men (n = 49), the mean was 17.73 (±2.91) kPa, whereas in the group of women (n = 51) it was 16.72 (±3.32) kPa. Statistical analyses showed no correlation between spleen stiffness and sex, age, weight, and BMI. Regarding their splenoportal axis, statistically significant differences in SS were found in the means of the two subgroups of subjects stratified by their portal flow velocity (p = 0.003) and spleen area (p < 0.001).Spearman's rank showed a weak association between SS and portal flow velocty (r = 0.271) and splenic area (r = −0.237). ICC showed excellent (0.96) inter-operator agreement and Bland–Altman plot demonstrated no systematic over/under-estimation of spleen stiffness values.ConclusionsOur results may serve as a reference point in the evaluation of SS especially in patients affected by advanced liver disease.     

Corticosteroids prevent the progression of autoimmune pancreatitis to chronic pancreatitis

Background/objectivesPatients with autoimmune pancreatitis (AIP) sometimes progress to chronic pancreatitis (CP). We evaluated the ability of corticosteroids to prevent the progression to CP.MethodsWe defined patients with definitive findings of CP (stones in the main pancreatic duct [MPD] or multiple pancreatic calcifications) as having severe calcification (SC). A total of 145 AIP patients were enrolled. We measured the duration between AIP diagnosis and SC development and retrospectively compared the time to SC development between patients with and without steroids. Multivariate analysis for factors associated with SC were performed.ResultsNineteen (13%) patients progressed to SC. Since 95 patients had pancreatic head swelling and SC was found in these patients only, our analysis focused mainly on these at-risk populations. In Kaplan-Meier analysis limited to patients with pancreatic head swelling, the incidence of SC was significantly lower in patients with steroids than in those without (hazard ratio [HR] 0.18, 95% confidence interval [CI] 0.07–0.52; p < 0.001). Multivariate testing of patients with pancreatic head swelling confirmed that steroid therapy was significantly associated with a lower incidence of SC (HR 0.11, 95% CI 0.03–0.34; p < 0.001), while MPD dilation at AIP diagnosis was related to a higher incidence of SC (HR 4.02, 95% CI 1.43–11.7; p = 0.009).ConclusionsCorticosteroids appeared to prevent progression to CP in AIP patients, especially in those with pancreatic head swelling. Patients with both pancreatic head swelling and MPD dilation at diagnosis have a higher incidence of progression to CP. Steroid therapy is suggested for these high-risk cases.     

A proposal of a diagnostic algorithm with validation of International Consensus Diagnostic Criteria for autoimmune pancreatitis in a Japanese cohort

BackgroundAmong many diagnostic criteria for autoimmune pancreatitis (AIP), the International Consensus Diagnostic Criteria (ICDC) first enabled us to diagnose and compare type 1 and type 2 AIP, which permitted tailoring individual diagnostic algorithms depending on local expertise. We compared them and validated ICDC with special reference to levels 1 and 2, and proposed a diagnostic algorithm for AIP in Japan.MethodsThe diagnostic sensitivity of 5 major criteria (ICDC, Korean, Japanese-2011, Asian, and HISORt criteria) was compared, using 61 patients with AIP. Fifty six patients with pancreatic cancer served as a control. Pancreas imaging on computed tomography (CT) and endoscopic retrograde pancreatography (ERP) were independently evaluated by 3 pancreatologists (5, 10, and 20 years of career experience) and each diagnostic criterion of ICDC was validated with special reference to levels 1 and 2.ResultsThe sensitivities of 5 major criteria were 95.1% (ICDC), 90.2% (Korean), 86.9% (Japanese), 83.6% (Asian), and 83.6% (HISORt) with 100% of specificity in each. In the evaluation of pancreas imaging, diagnostic sensitivities of combination with CT and ERP in segmental/focal type AIP were significantly higher than single imaging (26% in CT (P < 0.01) or 35% in ERP (P < 0.05) vs 63% in CT + ERP), but not significantly different in the diffuse type.ConclusionsOf the 5 criteria, ICDC is the most sensitive and useful for diagnosing AIP. We have proposed a diagnostic algorithm with CT for the diffuse type of AIP, and combination with CT + ERP followed by EUS-FNA for the segmental/focal type.     

Efficacy of pancreatic stenting prior to extracorporeal shock wave lithotripsy for pancreatic stones

BackgroundExtracorporeal shock wave lithotripsy is the first-line therapy for large pancreatic duct stones; however, it requires a long duration of therapy.AimsTo clarify the effect of pancreatic stenting prior to extracorporeal shock wave lithotripsy on shortening the duration of therapy and reducing complications.MethodsWe retrospectively compared 45 patients who underwent pancreatic stenting prior to extracorporeal shock wave lithotripsy (stenting group) and 35 patients who did not undergo stenting prior to extracorporeal shock wave lithotripsy (non-stenting group) with regard to the cumulative number of shock waves required for stone fragmentation (stone size <3 mm) and the rate of complications.ResultsThe stenting group was associated with a significantly lower cumulative number of shock waves in univariate analysis (log-rank, p = 0.046) and multivariate Cox proportional hazard analysis (hazard ratio, 1.88; 95% confidence interval, 1.13–3.14; p = 0.015) than the non-stenting group. The frequency of pancreatitis tends to be lower in the stenting group than the non-stenting group (2.2% [1/45] vs 11.4% [4/35]; p = 0.162).ConclusionsPancreatic stenting prior to extracorporeal shock wave lithotripsy reduced the cumulative number of shock waves required for pancreatic stone fragmentation, and could be useful to shorten the duration of therapy.     

Identification of commensal flora-associated antigen as a pathogenetic factor of autoimmune pancreatitis

ObjectivesAutoimmune pancreatitis (AIP) is a chronic fibro-inflammatory disease of the pancreas constituting, in part, a recently defined nosological entity of IgG4-related systemic sclerosing diseases. The pathogenetic factors of AIP have not been fully elucidated. We previously established a mouse model of AIP using chronic exposure to a commensal bacteria, Escherichia coli.MethodsTo determine the pathogenetically relevant antigen of E. coli, the outer membrane fractions of E. coli were subjected to two-dimensional gel electrophoresis followed by immunoblotting against sera from the AIP model. Immunoreactive spots were determined using MALDI TOF/MS and Mascot search. The recombinant protein of the identified antigen was examined for their ability to induce AIP-like disorder in C57BL/6 mice. Furthermore, the antibody titer against that antigen was determined in AIP patients.ResultsOne representative spot reacting with sera from E. coli-inoculated mice was identified as FliC from E. coli, based on the results of TOF/MS. The repeated inoculation of recombinant FliC in C57BL/6 mice induced AIP-like pancreatitis and higher titers of anti-lactoferrin and anti-carbonic anhydrase II. Sera from patients with AIP had the highest antibody titer, while those from patients with pancreatic diseases other than AIP had a higher antibody titer against E. coli and FliC, compared with pancreatic disease-free controls.ConclusionsFliC from E. coli may pathogenetically generate an AIP-like inflammation status. A reconsideration of the importance of commensal bacteria as an environmental factor(s) capable of inducing autoimmunity could provide insight to overcoming AIP.     

Demystifying seronegative autoimmune pancreatitis

BackgroundAutoimmune pancreatitis (AIP) has been classified into type 1 and type 2 subtypes. Serum immunoglobulin G4 (IgG4) elevation characterizes type 1 AIP. Type 2 AIP and a subset of type 1 AIP are seronegative, i.e., have normal serum IgG4 levels.AimWe compared the profiles of the three subsets of AIP to identify the unique characteristics of seronegative type 1 AIP and type 2 AIP.MethodsWe compared the clinical profiles of 69 seropositive type 1 AIP patients, 21 seronegative type 1 AIP patients and 22 type 2 AIP patients.ResultsAmong type 1 AIP, seronegative group had similar clinical profiles when compared to seropositive group except that they were more likely to undergo surgical resection than seropositive patients (p = 0.001). Seronegative type I AIP patients were older (61.9 ± 13.7 vs 45.3 ± 17.4; p = 0.004), and differed in the occurrence of other organ involvement (OOI) (71.4% vs 0%; p < 0.001) and disease relapse (33.3% vs 0%; p = 0.005) when compared with type 2 AIP. All seronegative type 1 AIP patients had at least one of the following –OOI, disease relapse, and age >50 years while none of the type 2 AIP had OOI or disease relapse.ConclusionsSeronegative and seropositive type 1 AIP patients have similar clinical profiles, which are distinct from that of type 2 AIP. Among the seronegative AIP group, patients are more likely to have type 1 AIP rather than type 2 AIP if they are older than 50 years or have OOI or disease relapse.     

Increase diagnostic accuracy in differentiating focal type autoimmune pancreatitis from pancreatic cancer with combined serum IgG4 and CA19-9 levels

Background/objectivesTo distinguish autoimmune pancreatitis (AIP), especially focal type, from pancreatic cancer, is a greatest challenge for clinician. The aim of the study is to compare the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of combined serum IgG4 and CA19-9 levels to differentiate AIP from pancreatic cancer by HISORt, Asian and international consensus diagnostic criteria.MethodsWe measured serum IgG4, CEA, and CA19-9 levels in 188 AIP patients, 86 non-AIP chronic pancreatitis patients, and 130 pancreatic cancer patients. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy were compared with different diagnostic criteria. We also compared the diagnostic performance in patients with or without jaundice.ResultsThe serum level of IgG4 was significantly higher in AIP than those in non-AIP chronic pancreatitis and pancreatic cancer. The optimal cutoffs of IgG4 and CA19-9 to differentiate AIP from pancreatic cancer were 175 mg/dL and 85.0 U/ml based on ROC analysis. Combining IgG4 level over 280 mg/dL and CA19-9 below 85.0 U/ml could yield a best diagnostic accuracy (85.6%) to distinguishing AIP from pancreatic cancer in all of the HISORt, Asian and international consensus diagnostic criteria. With the combination of serological test, focal type AIP could be diagnosed with comparable accuracy as diffuse type AIP.ConclusionsOur study demonstrated that combined use of serum IgG4 (over 280 mg/dL) and CA19-9 9 (below 85.0 U/ml) together increases the diagnostic accuracy to distinguish AIP from pancreatic cancer non-invasively, especially in focal type autoimmune pancreatitis.     

两种超声弹性成像技术诊断慢性乙型肝炎患者肝纤维化价值比较*

目的 探讨瞬时弹性成像和二维剪切波弹性成像用于CHB患者肝纤维化诊断的临床价值。方法 2016年3月～2018年12月我院收治的CHB患者164例,均行瞬时弹性成像和二维剪切波弹性成像检查及肝穿刺活检,采用受试者工作特性(ROC)曲线下面积比较两种超声弹性成像检查诊断不同肝纤维化分期的效能。结果 经肝穿刺活检,在164例CHB患者中,诊断肝组织S₁期50例,S₂期42例,S₃期39例,S₄期33例;瞬时弹性成像检查S₁～S₄期肝纤维化分期的弹性值分别为(6.5±1.1)kPa、(8.6±1.4)kPa、(11.7±1.8)kPa和(16.3±1.8)kPa,二维剪切波弹性成像检查弹性值分别为(5.9±0.8) kPa、(8.1±1.2)kPa、(10.9±1.5)kPa和(16.7±1.9) kPa,两种超声弹性成像检查不同肝纤维化分期弹性值差异无统计学意义(P >0.05);二维剪切波弹性成像检查诊断肝纤维化S₂、S₃和S₄期的ROC曲线下面积(AUC)分别为0.971、0.979和0.973,显著高于瞬时弹性成像检查的0.902、0.906和0.904(P <0.05),其诊断的敏感性分别为90.3%、90.6%和100.0%,特异性分别为95.8%、90.6%和84.5%,而瞬时弹性成像检查诊断则分别为78. 5%、81.3%和73.1%,和93.3%、87.9%和91.0%。结论 二维剪切波弹性成像和瞬时弹性成像检查均可用于慢性乙型肝炎患者的肝纤维化诊断,其临床价值均需要进一步探讨。     

Role of ultrasound shear wave elastography in preoperative prediction of pancreatic fistula after pancreaticoduodenectomy

BackgroundMajority of predictors of postoperative pancreatic fistula (POPF) use intraoperative variables. We aimed to study the role of preoperative ultrasound shear wave elastography (USWE) to predict POPF.MethodsThe consecutive patients who underwent pancreaticoduodenectomy (PD) between January 2019 to March 2020 were prospectively enrolled. All patients underwent USWE assessment at the pancreatic neck level. Intraoperative variables including pancreatic texture, pancreatic duct diameter, blood loss and histological grading of fibrosis were also recorded. Associations between USWE and intraoperative variables and histological grading with the development of POPF were analyzed.ResultsOf the 62 patients assessed, 50 patients (mean age: 53 ± 14 years; 31 males) were included. POPF and clinically relevant POPF (CRPOPF) were observed in 22 (44%) and 7 (14%) patients respectively. Soft pancreas was an independent predictor of CRPOPF (p = 0.04). The mean USWE valve was significantly lower in patients with CRPOPF as compared to no CRPOPF (9.7 Kpa vs. 12.8Kpa, p = 0.016). At receiver operating characteristic curve analysis, USWE value of 12.65Kpa yielded sensitivity and specificity of 100% and 47%, respectively, for prediction of CRPOPF. USWE showed significant correlation with intraoperative pancreatic texture (Spearman’s rank correlation coefficient (ρ) = 0.565, p = 0.001).ConclusionUSWE helps in preoperative prediction of CRPOPF. This may further help to customize management strategy in high risk patients.