Tropical calcific pancreatitis and fibrocalculus pancreatic diabetes in Bangladesh

mutTCPdb: a comprehensive database for genomic variants of a tropical country neglected disease-tropical calcific pancreatitis

Tropical calcific pancreatitis (TCP) is a juvenile, non-alcoholic form of chronic pancreatitis with its exclusive presence in tropical regions associated with the low economic status. TCP initiates in the childhood itself and then proliferates silently. mutTCPdb is a manually curated and comprehensive disease specific single nucleotide variant (SNV) database. Extensive search strategies were employed to create a repository while SNV information was collected from published articles. Several existing databases such as the dbSNP, Uniprot, miRTarBase2.0, HGNC, PFAM, KEGG, PROSITE, MINT, BIOGRID 3.4 and Ensemble Genome Browser 87 were queried to collect information specific to the gene. mutTCPdb is running on the XAMPP web server with MYSQL database in the backend for data storage and management. Currently, the mutTCPdb enlists 100 variants of all 11 genes identified in TCP, out of which 45 are non-synonymous (missense, nonsense, deletions and insertions), 46 are present in non-coding regions (UTRs, promoter region and introns) and 9 are synonymous variants. The database is highly curated for disease-specific gene variants and provides complete information on function, transcript information, pathways, interactions, miRNAs and PubMed references along with remarks. It is an informative portal for clinicians and researchers for a better understanding of the disease, as it may help in identifying novel targets and diagnostic markers, hence, can be a source to improve the strategies for TCP management.

Database URL: http://lms.snu.edu.in/mutTCPDB/index.php

Anthropometric measurements of nutritional status in chronic pancreatitis in India: comparison of tropical and alcoholic pancreatitis

AIM

Undernutrition is considered to be a cause of tropical pancreatitis (TP) since this disease is commonly seen in the underprivileged populations of the world. This study was done to compare the nutritional status in patients with TP and alcoholic chronic pancreatitis (ACP) using anthropometric measurements.

METHODS

Anthropometric measurements were done in patients with TP and ACP aged >18 years and matched healthy controls. Presence of pain, recent dietary restriction, diabetes mellitus (DM), calcification, serum prealbumin (PAB), and quantitative fecal elastase (FE) was assessed. Premorbid body mass index (BMI) was determined from weight before the onset of illness as reported by the patients.

RESULTS

Of 54 patients (47 male), 39 (72.2%) had TP and the rest had ACP. Patients with TP were younger than those with ACP; the frequency of pain, DM, calcification, and exocrine insufficiency was similar in the two groups. Compared to control subjects, patients had lower BMI, triceps skin fold thickness (TSFT) and mid-arm circumference (MAC) (p < 0.01), but waist-to-hip ratio (W/H) was similar. Undernutrition was equally common in TP and ACP (15 [38.5%] vs. 6 [40%]). The BMI, TSFT, MAC, and W/H were similar in TP and ACP. The premorbid BMI was higher than that at presentation (20.2 [3.8] kg/m² vs. 19.1 [3.3] kg/m², p < 0.01). There was no association between BMI and features contributing to undernutrition (DM, pain, recent dietary restriction, FE level, and calcification) on univariate analysis.

CONCLUSIONS

Energy undernutrition occurs equally commonly in TP and ACP and this appears to develop after the onset of illness.

Clinical profile of idiopathic chronic pancreatitis in North India

BACKGROUND & AIMS

Tropical pancreatitis, a form of idiopathic chronic pancreatitis (ICP) with unique features, has been described in South and North India. We investigated the clinical profile of ICP patients in North India.

METHODS

Detailed demographic data were recorded; hematological and biochemical analyses were performed on samples from 155 patients (mostly from North India) who had been diagnosed with chronic pancreatitis. Ultrasonography and computed tomography were performed on all patients. Magnetic resonance cholangiopancreatography, endoscopic retrograde cholangiopancreatography, glucose tolerance tests, and fecal fat studies were performed on some patients. Patients were divided into groups based on early- or late-onset ICP (before or after 35 years of age).

RESULTS

ICP was reported in 41.3% of patients and alcoholic chronic pancreatitis in 38.1%. The mean age of ICP patients was 33.0 +/- 13.0 years and the mean duration of symptoms at the time of presentation was 40.2 +/- 34.4 months. Pain was the dominant symptom in patients with early- (95.1%) and late-onset (100%) ICP; pseudocyst was the most common local complication. Diabetes was observed in 17.1% of patients with early-onset ICP and 34.8% with late-onset ICP. Pancreatic calcification was noted in 46.3% of patients with early-onset and 47.8% with late-onset ICP. Pseudocyst and segmental portal hypertension occurred more frequently in non-calcific ICP, whereas diabetes mellitus and abnormal fecal fat excretion occurred more frequently in patients with calcific ICP.

CONCLUSIONS

In North India, ICP differs from the classical tropical pancreatitis described in the literature. It is associated with a higher prevalence of pain and lower frequencies of diabetes, calcification, and intraductal calculi.

Natural history of endocrine failure in tropical chronic pancreatitis: a longitudinal follow-up study

BACKGROUND AND AIMS

Diabetes in tropical chronic pancreatitis (TCP), also known as fibrocalculous pancreatic diabetes (FCPD), is frequently seen at diagnosis. The aim of the present study was to determine the natural history of endocrine failure in TCP subjects without diabetes at baseline.

METHODS

Of 73 TCP subjects without diabetes according to World Health Organization (WHO) criteria at baseline who were seen at an out-patient center, 54 (74.0%) underwent periodic oral glucose tolerance tests on follow up. Another 54 sex-matched, non-diabetic subjects without chronic pancreatitis served as controls. Baseline demographic and clinical characteristics were noted.

RESULTS

After a median follow up of 5.0 years in TCP subjects and 7.0 years in controls, 27 of 54 TCP subjects (50%) developed diabetes compared with 14 of 54 controls (25.9%). Of the TCP subjects, those who developed diabetes on follow up were older (31 +/- 12 vs 23 +/- 11 years; P = 0.013), had a higher body mass index (21.7 +/- 4.4 vs 18.2 +/- 3.5 kg/m2; P = 0.004), higher 2 h post-load plasma glucose (8.8 +/- 1.9 vs 6.7 +/- 1.4 mmol/L; P < 0.001) and lower fecal chymotrypsin (2.1 +/- 1.2 vs 4.3 +/- 2.5 U/g; P < 0.001) at baseline compared with those who did not develop diabetes. The median time for the development of diabetes after diagnosis of TCP was 9.6 years (compared with 14.4 years among controls). Only 2 of 13 TCP subjects (15.4%) who had undergone surgical interventions during the normal glucose tolerance phase developed diabetes during follow up.

CONCLUSIONS

In TCP, there is progressive deterioration of endocrine pancreatic function, with development of diabetes in 50% of patients upon follow up, suggesting that FCPD is merely a later stage in the course of TCP. Early surgery may prevent the development of diabetes in TCP subjects.

Serine Protease Inhibitor Kazal Type 1 Mutations and Pancreatitis

SPINKI is thought to play an important role in protecting the pancreas against excessive trypsinogen activation. SPINK1 mutations are associated with the development of acute and chronic pancreatitis and have been detected in all forms of chronic pancreatitis. The strong association of mutations in the PRSS1 gene and in the SPINKI gene with chronic pancreatitis supports the concept of intracellular trypsin activation as an initiating and extremely important step in the development of pancreatitis. The N34S mutation represents the most frequently observed pancreatitis-associated SPINKI variant. Because the SPINKI N34Smutation is very common in the general population, it is unlikely that this mutation alone can initiate the development of chronic pancreatitis. Thus, it rather appears that in most patients with SPINKI-associated chronic pancreatitis, this genetic variant acts as disease modifier or within a polygenic model with other yet unidentified genes or environmental co-factors. The possible interaction of mutations in the SPINK1 gene with other pancreatitis-associated susceptibility genes has to be investigated in future research efforts. The most promising candidate gene for such an interaction is the CFTR gene, because genetic alterations within the CFTRgene are also common in the general population and already have been associated with chronic pancreatitis.

Serine protease inhibitor Kazal type 1 mutations and pancreatitis

In summary, SPINK1 is thought to play an important role in protecting the pancreas against excessive trypsinogen activation. SPINK1 mutations are associated with the development of acute and chronic pancreatitis and have been detected in all forms of chronic pancreatitis. The strong association of mutations in the PRSS1 gene and in the SPINK1 gene with chronic pancreatitis supports the concept of intracellular trypsin activation as an initiating and extremely important step in the development of pancreatitis. The N34S mutation represents the most frequently observed pancreatitis-associated SPINK1 variant. Because the SPINK1 N34S mutation is very common in the general population, it is unlikely that this mutation alone can initiate the development of chronic pancreatitis. Thus, it rather appears that in most patients with SPINK1-associated chronic pancreatitis, this genetic variant acts as disease modifier or within a polygenic model with other yet unidentified genes or environmental cofactors. The possible interaction of mutations in the SPINK1 gene with other pancreatitis-associated susceptibility genes has to be investigated in future research efforts. The most promising candidate gene for such an interaction is the CFTR gene, because genetic alterations within the CFTR gene are also common in the general population and already have been associated with chronic pancreatitis.

Diabetes mellitus in Tropical Chronic Pancreatitis Is Not Just a Secondary Type of Diabetes

AIMS

In chronic calcific pancreatitis of the tropics, etiology and relationship to developing diabetes mellitus are unknown. Some consider these cases a straightforward secondary type of diabetes, while others suggest selective beta-cell impairment. Testing pancreatic function, we investigated whether selective beta-cell impairment triggers diabetes associated with tropical pancreatitis.

METHODS

At a Bangladeshi research institute, 8 chronic tropical pancreatitis and no diabetes mellitus subjects, 14 fibrocalculous pancreatic diabetics and 27 matched healthy controls underwent arginine (endocrine pancreatic function) and secretin (exocrine pancreatic function assessment) stimulation tests.

RESULTS

All patients with clinically-diagnosed, chronic pancreatitis demonstrated pronounced exocrine pancreatic dysfunction with beta-cell functioning differing significantly between the two groups. Compared to controls, patients having tropical pancreatitis and no diabetes showed normal plasma C-peptide values at baseline and after arginine stimulation, while fibrocalculous pancreatic diabetics demonstrated a typical diabetic pattern for plasma C-peptide levels. In contrast, pancreatic alpha-cell functioning (glucagon response to arginine) was preserved in both pancreatitis groups.

CONCLUSION

A preserved pancreatic alpha-cell function in diabetics with advanced chronic pancreatitis of the tropics supports the concept of two different pathogenic mechanisms, one eliciting chronic pancreatitis and the other selective pancreatic beta-cell impairment and subsequent diabetes mellitus.

Hereditary pancreatitis as the premalignant disease: a Japanese case of pancreatic cancer involving the SPINK1 gene mutation N34S

Mutations in the cationic trypsinogen gene are acknowledged as a risk factor for pancreatic cancer in patients with hereditary pancreatitis. However, whether patients with mutations in other genes, such as the serine protease inhibitor Kazal type 1 (SPINK1) gene, are also at a higher risk of pancreatic cancer remains unknown. We report a case of pancreatic cancer associated with chronic calcifying pancreatitis in a patient with a homozygous N34S mutation in the SPINK1 gene. A 44-year-old woman was hospitalized due to obstructive jaundice. Preoperative examination showed a tumor in the head of the pancreas and multiple pancreatic stones; pancreatoduodenectomy revealed a solid tumor, 3.0 x 2.5 cm in size, in the head of the pancreas, and numerous pancreatic stones throughout the pancreas. Pathologic studies revealed moderately differentiated tubular adenocarcinoma. Mutational analyses of the SPINK1 and PRSS1 genes in members of the patient's family were carried out. The homozygous N34S mutation in the SPINK1 gene was found in the patient and her older sister, who was previously diagnosed with chronic calcific pancreatitis and had undergone the Frey operation. The patient's parents and brother were unaffected carriers of the N34S heterozygous mutation. No family members had any mutations in the cationic trypsinogen gene. To our knowledge, this is the first reported case of chronic pancreatitis accompanied by pancreatic cancer in a patient with the SPINK1 N34S mutation. Although this case does not meet the classic criteria of hereditary pancreatitis, it does suggest that the SPINK1 N34S mutation may be associated with cancer development in patients with hereditary pancreatitis. Further prospective, multicenter trials investigating secondary screening for pancreatic cancer in hereditary pancreatitis are necessary to clarify the role of SPINK1 mutations in the development of pancreatic cancer.

Tropical chronic pancreatitis

Tropical chronic pancreatitis (TCP) is a juvenile form of chronic calcific non-alcoholic pancreatitis, seen almost exclusively in the developing countries of the tropical world. The classical triad of TCP consists of abdominal pain, steatorrhoea, and diabetes. When diabetes is present, the condition is called fibrocalculous pancreatic diabetes (FCPD) which is thus a later stage of TCP. Some of the distinctive features of TCP are younger age at onset, presence of large intraductal calculi, more aggressive course of the disease, and a high susceptibility to pancreatic cancer. Pancreatic calculi are the hallmark for the diagnosis of TCP and in non-calcific cases ductal dilation on endoscopic retrograde cholangiopancreatography, computed tomography, or ultrasound helps to identify the disease. Diabetes is usually quite severe and of the insulin requiring type, but ketosis is rare. Microvascular complications of diabetes occur as frequently as in type 2 diabetes but macrovascular complications are uncommon. Pancreatic enzyme supplements are used for relief of abdominal pain and reducing the symptoms related to steatorrhoea. Early diagnosis and better control of the endocrine and exocrine dysfunction could help to ensure better survival and improve the prognosis and quality of life of TCP patients.

Tropical calcific pancreatitis: strong association with SPINK1 trypsin inhibitor mutations

BACKGROUND & AIMS

Tropical calcific pancreatitis (TCP) is a chronic pancreatitis unique to developing countries in tropical regions. The cause of TCP is obscure. Whereas environmental factors, such as protein energy malnutrition and ingestion of cassava, have been implicated, a genetic predisposition to the disease also may be important. In the present study we report on mutations in the serine protease inhibitor, Kazal type 1 (SPINK1) gene in north Indian patients with TCP.

METHODS

We studied 66 unrelated TCP patients (44 men, 49 with diabetes, and 6 with family history of TCP), 25 relatives, and 92 healthy control subjects. Samples were analyzed for SPINK1 variants (-53C>T, L14P, N34S, P55S, and 272T>C) and cationic trypsinogen (PRSS1) variants (A16V, K23R, N29I, and R122H) by melting curve analysis.

RESULTS

Twenty-nine patients (44%) carried the N34S missense mutation, of whom 9 (14%) were homozygotes. In contrast, only 2 (2.2%) control subjects were N34S heterozygotes (prevalence ratio 20.2; 95% confidence interval 5.0-81.8; P < 0.0001 vs. TCP). The severity of pancreatitis did not differ between TCP patients with or without N34S, or among those heterozygous or homozygous for N34S. Among TCP patients with or without diabetes, the frequency of N34S carriers (43% vs. 47%) and N34S homozygotes (14% vs. 12%) was similar.

CONCLUSIONS

TCP is highly associated with the SPINK1 N34S mutation. The high prevalence of N34S in TCP patients with and without diabetes suggests that these 2 subtypes have a similar genetic predisposition. The genetic predisposition to TCP resembles, at least in part, the idiopathic chronic pancreatitis found in industrialized countries.

SPINK1/PSTI mutations are associated with tropical pancreatitis and type II diabetes mellitus in Bangladesh

BACKGROUND & AIMS

Tropical pancreatitis, including tropical calcific pancreatitis and fibrocalculous pancreatic diabetes, is endemic in parts of Asia and Africa. In a preliminary study, we found serine protease inhibitor, Kazal type 1 (SPINK1) mutations in 6 of 8 patients with fibrocalculous pancreatic diabetes in Bangladesh. A more extensive investigation of patients with pancreatic diseases in Bangladesh, including non-insulin-dependent diabetes mellitus, was undertaken.

METHODS

Patients with fibrocalculous pancreatic diabetes (n = 22), tropical calcific pancreatitis (n = 15), and non-insulin-dependent diabetes mellitus (n = 43) and controls (n = 76) from Bangladesh were studied. DNA was extracted, and the SPINK1 gene was sequenced in all patients and 50 controls. Exon 3 was sequenced in an additional 26 controls.

RESULTS

SPINK1 N34S mutations appeared in 1 of 76 controls (1.3%), 12 of 22 patients with fibrocalculous pancreatic diabetes (55%; odds ratio, 83; P < 0.00001), 3 of 15 with tropical calcific pancreatitis (20%; odds ratio, 11.2; P = 0.04), and 6 of 43 with non-insulin-dependent diabetes mellitus (14%; odds ratio, 11.9; P = 0.009). P55S was present in 2 of 76 controls (3%) and in 1 of 22 patients with fibrocalculous pancreatic diabetes (5%; P = not significant). A novel Y54H (160T>C) mutation was identified in 1 of 15 tropical calcific pancreatitis patients.

CONCLUSIONS

In Bangladesh, the SPINK1 N34S mutation increases the risk of several forms of pancreatic disease, including fibrocalculous pancreatic diabetes, tropical calcific pancreatitis, and non-insulin-dependent diabetes mellitus.

SPINK1/PSTI mutations are associated with tropical pancreatitis in Bangladesh. A preliminary report

BACKGROUND/AIMS

Tropical pancreatitis (TP) refers to a severe type of idiopathic chronic pancreatitis that develops in children in tropical regions of Africa and southern Asia. Phenotypically TP is subdivided into fibrocalculous pancreatic diabetes (FCPD) and tropical calcific pancreatitis without diabetes mellitus (TCP). Recently an association was identified between idiopathic pancreatitis in the USA and Europe and mutations in the serine protease inhibitor, Kazal type 1 (SPINK1) gene (previously termed pancreatic secretory trypsin inhibitor, PSTI). Our aim was to determine if either form of TP has a genetic basis.

METHODS

We studied 8 well-characterized patients from Bangladesh with FCPD, 4 with TCP and 4 controls without pancreatic disease. The entire SPINK1 gene was sequenced in these patients.

RESULTS

We detected two disease-associated SPINK1 mutations (N34S/IVS1 - 37T > C and IVS3 + 2T > C) in 6 of 8 patients from Bangladesh with FCPD but not in 4 patients with TCP (p < 0.03) or 4 controls (p < 0.03).

CONCLUSIONS

We conclude that SPINK1 mutations are associated with FCPD in Bangladesh. Since SPINK1 mutations in Europeans and North Americans are associated with idiopathic chronic pancreatitis that is phenotypically different from FCPD, we further conclude that mutated SPINK1 markedly increases the risk of developing a variety of pancreatic diseases possibly through a chronic elevation of active trypsin within the pancreas.

SPINK1 mutations are associated with multiple phenotypes

Mutations in the gene encoding for the pancreatic secretory trypsin inhibitor or serine protease inhibitor, Kazal type I (SPINK1) have been associated with different entities of chronic pancreatitis. While there is no doubt about the involvement of SPINK1 mutations in pancreatic inflammatory disease, much controversy has arisen regarding which alterations are associated with disease and what type of disease model should be applied when the SPINK1 gene is examined. This article presents the existing data on SPINK1 mutations in idiopathic chronic pancreatitis, familial pancreatitis, hereditary pancreatitis and tropical pancreatitis. The possible role of SPINK1 mutations and polymorphisms in pancreatic disease is discussed.

Genetic susceptibility to fibrocalculous pancreatic diabetes in Bangladeshi subjects: a family study

Fibrocalculous pancreatic diabetes (FCPD) is an uncommon cause of diabetes, seen mainly in developing countries. A family-based study was carried out in 67 Bangladeshi families, consisting of a proband with FCPD and both parents, to determine whether an association exists between FCPD susceptibility and either the major histocompatiblity complex (MHC) or insulin gene (INS) loci. HLA-DQB1 typing was done using allele-specific primers, and INS was typed using the restriction enzyme HphI. Three microsatellites (TNFa, TNFc and TNFd), from within and flanking the TNF-LT locus, were used for MHC Class IV typing and a PCR-RFLP assay was used to define the -308G/A TNF promoter polymorphism. The extended transmission disequilibrium test (ETDT) was used for statistical analysis. An overall association was observed between FCPD and HLA-DQB1 (P = 0.003), that was largely due to a positive association with HLA-DQB1*0302 and a negative association with HLA-DQB1*0202. Although no association was found between FCPD and TNF-LT microsatellite markers a trend was observed for TNFc (P = 0.037, Pc = 0.15). No association was found between FCPD and INS (P = 0.26). This study confirms an association between FCPD and the MHC using a family-based study design and the stringent ETDT analysis; a novel protective association was found with HLA-DQB1*0202 in Bangladeshi FCPD subjects. The genetic susceptibility to FCPD has features both similar and dissimilar to T1DM.