Relapsing pancreatitis due to a novel compound heterozygosity in the CFTR gene involving the second most common mutation in central and eastern Europe [CFTRdele2,3(21 kb)]

Acute Relapsing Pancreatitis with Pseudocyst Formation due to Sporadic Hypertriglyceridemic Pancreatitis: A Case Report

Acute pancreatitis is one of the common causes of the acute abdomen that should be included in any differential diagnosis for acute abdominal pain; it is also well known with its variant causes, of which most common is biliary tree stones, alcoholic pancreatitis, followed by a long list of other less common causes. We have reported a rare case of relapsing acute pancreatitis due to atypical sporadic hypertriglyceridemia (Frederickson's type IV) in a young male patient who was seen in the accident and emergency department presenting with severe agonizing abdominal pain, with history of recurrent similar attacks, which were unfortunately misdiagnosed elsewhere.

Compound heterozygous mutations affect protein folding and function in patients with congenital sucrase-isomaltase deficiency

BACKGROUND & AIMS

Congenital sucrase-isomaltase (SI) deficiency is an autosomal-recessive intestinal disorder characterized by a drastic reduction or absence of sucrase and isomaltase activities. Previous studies have indicated that single mutations underlie individual phenotypes of the disease. We investigated whether compound heterozygous mutations, observed in some patients, have a role in disease pathogenesis.

METHODS

We introduced mutations into the SI complementary DNA that resulted in the amino acid substitutions V577G and G1073D (heterozygous mutations found in one group of patients) or C1229Y and F1745C (heterozygous mutations found in another group). The mutant genes were expressed transiently, alone or in combination, in COS cells and the effects were assessed at the protein, structural, and subcellular levels.

RESULTS

The mutants SI-V577G, SI-G1073D, and SI-F1745C were misfolded and could not exit the endoplasmic reticulum, whereas SI-C1229Y was transported only to the Golgi apparatus. Co-expression of mutants found on each SI allele in patients did not alter the protein's biosynthetic features or improve its enzymatic activity. Importantly, the mutations C1229Y and F1745C, which lie in the sucrase domains of SI, prevented its targeting to the cell's apical membrane but did not affect protein folding or isomaltase activity.

CONCLUSIONS

Compound heterozygosity is a novel pathogenic mechanism of congenital SI deficiency. The effects of mutations in the sucrase domain of SIC1229Y and SIF1745C indicate the importance of a direct interaction between isomaltase and sucrose and the role of sucrose as an intermolecular chaperone in the intracellular transport of SI.

Usefulness of technetium-99m hexamethylpropylene amine oxime-labeled leukocyte scintigraphy to detect pancreatic necrosis in patients with acute pancreatitis. Prospective comparison with Ranson, Glasgow and APACHE-II scores and serum C-reactive protein

BACKGROUND

In acute pancreatitis (AP), pancreatic necrosis (PN) is an important local complication that can be identified by means of contrast-enhanced computed tomography (CECT). Pancreatic leukocyte infiltration is a significant pathogenic event in the development of PN that can be detected by labeled leukocyte scintigraphy (LLS). The aim of this study was to evaluate the utility of LLS with technetium-99m hexamethylpropylene amine oxime ((99m)Tc-HMPAO) to detect the presence of PN in patients with AP.

METHODS

Prospective cohort study of 84 patients with AP. Patients underwent LLS and the activity of images was scored on a 0-3 scale. CETC was performed to assess PN. Ranson, Glasgow and APACHE-II scores were calculated. Serum C-reactive protein (CRP) was measured. Sensitivity (Sn), specificity (Sp), positive predictive values (PPV), negative predictive values (NPV), areas under receiver operating characteristic (ROC) curves, likelihood ratios, odds ratios, analysis of variances between groups and correlation coefficients between tests were calculated.

RESULTS

PN was present in 11 (13%) patients. Pancreatic labeled leukocyte uptake was present in 38 patients (45%). Sn, Sp, PPV and NPV of LLS grade 2-3 for PN diagnosis were the highest (91, 88, 53 and 98%, respectively) of all tests. Patients with LLS grade 2-3 were 71 times more likely to be at risk of PN compared to those with LLS grade 0-1. The area under ROC curve of the LLS was the largest. A significant correlation was obtained between LLS and CRP (p < 0.001).

CONCLUSION

In patients with AP, LLS with (99m)Tc-HMPAO detects PN with an acceptable level of confidence and therefore could be considered an alternative technique to CECT in detecting PN.

Relapsing pancreatitis due to a novel compound heterozygosity in the CFTR gene involving the second most common mutation in central and eastern Europe [CFTRdele2,3(21 kb)]

A 43-year-old otherwise healthy female patient presented with mild pancreatitis. Her family history revealed that her only son had cystic fibrosis. Genotyping of the patient demonstrated CFTR compound heterozygosity CFTRdele2,3(21 kb) and R117H and wild type alleles of the poly-T-tract in intron 8 (7T/7T). No mutations were detected in the cationic pancreatic trypsinogen (PRSS1) and the pancreatic secretory trypsinogen inhibitor (SPINK1) genes. CFTRdele2,3(21 kb) has only been described in 2000 and is the second most frequent severe CFTR mutation after DeltaF508 in central and eastern Europe. This haplotype should be included in the genetic panel when evaluating patients of central or eastern European genetic background for possible CFTR related pancreatitis.