Genetic Background and Clinical Characters of Pediatric Chronic Pancreatitis: Data and Implications from the East

Heterozygous Spink1 c.194+2T>C mutation promotes chronic pancreatitis after acute attack in mice

BACKGROUND & AIMS

Mutations in genes, including serine protease inhibitor Kazal-type 1 (SPINK1), influence disease progression following sentinel acute pancreatitis event (SAPE) attacks. SPINK1 c.194+2T > C intron mutation is one of the main mutants of SPINK1，which leads to the impairment of SPINK1 function by causing skipping of exon 3. Research on the pathogenesis of SAPE attacks would contribute to the understanding of the outcomes of acute pancreatitis. Therefore, the aim of the study was to clarify the role of SPINK1 c.194+2T > C mutation in the CP progression after an AP attack.

METHODS

SAPE attacks were induced in wildtype and SPINK mutant (Spink1 c.194+2T > C) mice by cerulein injection. The mice were sacrificed at 24 h, 14 d, 28 d, and 42 d post-SAPE. Data-independent acquisition (DIA) proteomic analysis was performed for the identification of differentially expressed protein in the pancreatic tissues. Functional analyses were performed using THP-1 and HPSCs.

RESULTS

Following SAPE attack, the Spink1 c.194+2T > C mutant mice exhibited a more severe acute pancreatitis phenotype within 24 h. In the chronic phase, the chronic pancreatitis phenotype was more severe in the Spink1 c.194+2T > C mutant mice after SAPE. Proteomic analysis revealed elevated IL-33 level in Spink1 c.194+2T > C mutant mice. Further in vitro analyses revealed that IL-33 induced M2 polarization of macrophages and activation of pancreatic stellate cells.

CONCLUSION

Spink1 c.194+2T > C mutation plays an important role in the prognosis of patients following SAPE. Heterozygous Spink1 c.194+2T > C mutation promotes the development of chronic pancreatitis after an acute attack in mice through elevated IL-33 level and the induction of M2 polarization in coordination with pancreatic stellate cell activation.

A narrative review on the role of genetics in children with acute recurrent pancreatitis and chronic pancreatitis

The incidence of pancreatitis in children has increased over the past two decades. With advances in molecular biological techniques and clinical research, genetic variations have emerged as a pivotal etiological factor in pediatric pancreatitis. This review aims to summarize recent clinical research advancements in understanding pediatric pancreatitis caused by various gene mutations. As of the year 2020, researchers had identified 12 genes implicated in the pathogenesis of pancreatitis. These genes primarily contributed to the development of pancreatitis through three mechanisms. Pancreatitis resulting from these gene mutations exhibits several distinct characteristics, including early onset, a heightened risk of developing pancreatic duct stones, rapid disease progression, and a significantly increased risk of pancreatic endocrine and exocrine dysfunction, as well as pancreatic cancer in the future. Genetic sequencing is recommended for children with pancreatitis based on six indications. The sequencing not only assists in the clinical diagnosis but also enhances our understanding of the pathophysiology of pancreatitis.

Genetic Investigations in Turkish Idiopathic Pancreatitis Patients Show Unique Characteristics

BACKGROUND/AIMS

Pancreatitis is one of the leading causes of digestive system-related hospital admissions, and it has a genetic background in a considerable portion of the patients. In this study, we aimed to investigate the genetic risk factors of idiopathic pancreatitis in Turkish patients and the contribution of copy number variations to the pathogenesis.

MATERIALS AND METHODS

Idiopathic pancreatitis is defined as failure to detect risk factors despite comprehensive clinical assessments. Next-generation sequencing and multiple ligand-dependent probe amplification of PRSS1, SPINK1, CTRC, and CFTR were performed. For further genotype-phenotype correlations, patients were also questioned for the age of onset, family history, and pancreatic divisum.

RESULTS

A total of 68 idiopathic pancreatitis cases were enrolled. Variants with potential clinical significance of PRSS1 were identified in 13.4%, SPINK1 in 6.3%, CTRC in 4.7%, and CFTR in 26.5% of the patients. No copy number variants were seen in any of these genes. At least 7.4% of the participants had complex genetic etiology involving 2 genes.

CONCLUSIONS

At least 42.6% of the participants had a potential genetic risk factor. Five novel genetic variants were identified, and distinctive genetic risk factors of Turkish population were shown. The results showed that genetic etiology was frequent in pancreatitis and it was even more prominent in patients with early-onset disease. Considering that genetic risk factors may be informative for decisionmaking in the treatment options in addition to providing extensive prognostic value and familial genetic consultation; clinicians need to be more eager to offer genetic tests to pancreatitis patients.

Pancreaticopleural fistula in a Thai boy with SPINK1 c.101A>G substitution variant-related chronic pancreatitis: a case report and literature review

Background

Chronic pancreatitis is the most common etiology of pancreaticopleural fistula (PPF) in children, and underlying genetic variations are now widely known, accounting for most chronic pediatric pancreatitis.

Case report

We describe a case of previously undetected chronic pancreatitis and PPF with a SPINK1 variation in a 10-year-old Thai boy who presented with massive left pleural effusion. Magnetic resonance cholangiopancreatography (MRCP) revealed disruption of the pancreatic duct, which was communicating with a large pancreatic pseudocyst with mediastinal extension. The patient subsequently underwent endoscopic intervention with improved clinical symptoms. We also reviewed the imaging findings of 12 other reported cases of pediatric PPF.

Conclusions

Massive pleural effusion due to PPF can be an atypical manifestation in children with chronic pancreatitis. MRCP is the preferable imaging study for PPF due to the production of highly detailed images of pancreatic duct disruptions and anatomy, and the imaging is helpful to guide for appropriate treatment. Tests for genetic variation are also recommended in a child with chronic pancreatitis.

Prevalence of Germline Sequence Variations Among Patients With Pancreatic Cancer in China

IMPORTANCE

A higher incidence of pancreatic cancer has been reported in the Chinese population compared with the White population, but genetic differences are unknown to date. Large-sample germline testing for both familial and sporadic pancreatic cancers has been conducted predominantly in White populations, whereas similar studies in Chinese populations are limited.

OBJECTIVE

To assess the prevalence of germline sequence variations in patients with pancreatic diseases in China.

DESIGN, SETTING, AND PARTICIPANTS

This genetic association study was a case series that included genetic data from patients with pancreatic ductal adenocarcinoma (PDAC) or non-PDAC pancreatic diseases seen at The First Affiliated Hospital of Nanjing Medical University in Nanjing, China, between January 2006 and December 2017 (Nanjing cohort). Comparator group data were obtained for a US cohort from Johns Hopkins Hospital (JHH), a population from East Asia from the Exome Aggregation Consortium (ExAC) database, and the larger population from China from the ChinaMAP database. Data were updated and analyzed in July 2021.

MAIN OUTCOMES AND MEASURES

Next-generation sequencing technology was used to examine the prevalence of deleterious variations in 59 genes of the included Chinese patients with DNA extracted from peripheral blood samples. The Fisher exact test was used to assess differences among the frequencies of germline variations in the study patients vs the comparator groups.

RESULTS

A total of 1009 patients with PDAC (627 [62.1%] male; mean [SD] age, 62.8 [10.2] years) and 885 with non-PDAC diseases (477 [53.9%] male; mean [SD] age, 52.0 [15.9] years) from the Nanjing cohort were included for genetic analysis; all were Han Chinese individuals. Pathogenic variations were detected in 63 patients with PDAC (6.2%; 95% CI, 4.7%-7.7%). Variations in BRCA2 (odds ratio [OR], 3.2; 95% CI, 1.4-7.7; P = .008) and PALB2 (OR, 5.2; 95% CI, 1.6-17.0; P = .007) were significantly associated with pancreatic risk in the Nanjing cohort. Pathogenic variants of genes associated with homologous recombination DNA damage repair, including ATM, BRCA1/2, PALB2, BRIP1, FANCA, FANCC, RAD51D, and XRCC2, were found in 34 patients with PDAC (3.4%). No Ashkenazi Jewish-specific BRCA2 variation (p.Ser1982fs) was detected. The odds ratio of a SPINK1 variation in patients with PDAC was 3.2 (95% CI, 1.8-5.7; P < .001) in the Nanjing cohort compared with the ExAC cohort. Variations in the pancreatic secretory enzyme genes CPA1 and CPB1 were not detected in the Nanjing cohort.

CONCLUSIONS AND RELEVANCE

In this genetic association study, sporadic pancreatic cancer was associated with pathogenic germline variations in a cohort from China. These findings provide insights into the genetic background of pancreatic cancer in the Han Chinese population with PDAC.

Clinical and Practice Variations in Pediatric Acute Recurrent or Chronic Pancreatitis: Report From the INSPPIRE Study

OBJECTIVE

The aim of the study was to determine whether clinical characteristics and management of pediatric acute recurrent pancreatitis (ARP) and chronic pancreatitis (CP) differ across INSPPIRE (INternational Study Group of Pediatric Pancreatitis: In Search for a cuRE) sites.

STUDY DESIGN

Data were collected from INSPPIRE and analyzed per US regions and "non-US" sites. Between-group differences were compared by Pearson chi-square test. Differences in disease burden were compared by Kruskal-Wallis test.

RESULTS

Out of the 479 subjects, 121 (25%) were enrolled in West, 151 (32%) Midwest, 45 Northeast (9%), 78 (16%) South, and 84 (18%) at non-US sites. Hispanic ethnicity was more common in South (P < 0.0001); white race in Northeast (P = 0.009). CP was less common and time from diagnosis of first acute pancreatitis to CP was longer in children at non-US sites (P = 0.0002 and P = 0.011, respectively). Genetic mutations were most common among all groups; PRSS1 variants predominated in Midwest (P = 0.002). Gallstones were more frequent in South (P = 0.002). Endoscopic retrograde cholangiopancreatography (ERCP) and computed tomography (CT) imaging were more commonly utilized in United States compared with non-United States (P < 0.0001), but there were no differences in the use of MRI/MRCP. Disease burden was highest in the West and Midwest, possibly as total pancreatectomy and islet autotransplantation (TPIAT) referral sites were located in these regions. All therapies were less commonly administered in non-US sites (P < 0.0001).

CONCLUSIONS

This is the first study to describe geographical variations in the INSPPIRE cohort, which possibly reflect variations in practice and referral patterns. The underlying reason behind the lower frequency of CP and fewer treatments in non-United States sites need to be further explored.