First Japanese Family With PDX1-MODY (MODY4): A Novel PDX1 Frameshift Mutation, Clinical Characteristics, and Implications

CONTEXT

The PDX1 gene encodes pancreatic and duodenal homeobox, a critical transcription factor for pancreatic β-cell differentiation and maintenance of mature β-cells. Heterozygous loss-of-function mutations cause PDX1-MODY (MODY4).

CASE DESCRIPTION

Our patient is an 18-year-old lean man who developed diabetes at 16 years of age. Given his early-onset age and leanness, we performed genetic testing. Targeted next-generation sequencing and subsequent Sanger sequencing detected a novel heterozygous frameshift mutation (NM_00209.4:c.218delT. NP_000200.1: p.Leu73Profs*50) in the PDX1 transactivation domain that resulted in loss-of-function and was validated by an in vitro functional study. The proband and his 56-year-old father, who had the same mutation, both showed markedly reduced insulin and gastric inhibitory polypeptide (GIP) secretion compared with the dizygotic twin sister, who was negative for the mutation and had normal glucose tolerance. The proband responded well to sitagliptin, suggesting its utility as a treatment option. Notably, the proband and his father showed intriguing phenotypic differences: the proband had been lean for his entire life but developed early-onset diabetes requiring an antihyperglycemic agent. In contrast, his father was overweight, developed diabetes much later in life, and did not require medication, suggesting the oligogenic nature of PDX1-MODY. A review of all reported cases of PDX1-MODY also showed heterogeneous phenotypes regarding onset age, obesity, and treatment, even in the presence of the same mutation.

CONCLUSIONS

We identified the first Japanese family with PDX1-MODY. The similarities and differences found among the cases highlight the wide phenotypic spectrum of PDX1-MODY.

Diagnosis and treatment of primary central nervous system lymphoma with the primary lesion in the hypothalamus: a case report

BACKGROUND

Primary central nervous system lymphoma is a rare extra-nodal lymphoma of the central nervous system. Primary central nervous system lymphoma lesions usually appear in the vicinity of the ventricle, and there are few reports of primary central nervous system lymphoma with hypothalamic-pituitary lesions.

CASE PRESENTATION

We treated a 56-year-old male with primary central nervous system lymphoma with the primary lesion in the hypothalamus, which was found by magnetic resonance imaging after sudden onset of endocrinological abnormalities. Initially, he was hospitalized to our department for hyponatremia. Endocrinological examination in conjunction with head magnetic resonance imaging and endoscopic biopsy revealed hypothalamic hypopituitarism and tertiary hypoadrenocorticism caused by a rapidly growing, diffuse large B-cell lymphoma in the hypothalamus. Remission of the tumor was achieved by high-dose methotrexate with whole brain radiotherapy, and some of the hormone responses were normalized.

CONCLUSIONS

While primary central nervous system lymphoma is rare, it is important to note that hypopituitarism can result and that the endocrinological abnormalities can be partially restored by its remission.

L-Arginine prevents cereblon-mediated ubiquitination of glucokinase and stimulates glucose-6-phosphate production in pancreatic β-cells

We sought to determine a mechanism by which L-arginine increases glucose-stimulated insulin secretion (GSIS) in β-cells by finding a protein with affinity to L-arginine using arginine-immobilized magnetic nanobeads technology. Glucokinase (GCK), the key regulator of GSIS and a disease-causing gene of maturity-onset diabetes of the young type 2 (MODY2), was found to bind L-arginine. L-Arginine stimulated production of glucose-6-phosphate (G6P) and induced insulin secretion. We analyzed glucokinase mutants and identified three glutamate residues that mediate binding to L-arginine. One MODY2 patient with GCK^E442* demonstrated lower C-peptide-to-glucose ratio after arginine administration. In β-cell line, GCK^E442* reduced L-arginine-induced insulin secretion compared with GCK^WT. In addition, we elucidated that the binding of arginine protects glucokinase from degradation by E3 ubiquitin ligase cereblon mediated ubiquitination. We conclude that L-arginine induces insulin secretion by increasing G6P production by glucokinase through direct stimulation and by prevention of degradation.

Using arginine-immobilized magnetic nanobeads, Cho et al. show that glucokinase, the key regulator of glucose-stimulated insulin secretion, binds L-arginine, which protects glucokinase from ubiquitination-mediated degradation while inducing insulin secretion. This study provides mechanistic insights into how L-arginine increases insulin production.

Clinical manifestations of a sporadic maturity-onset diabetes of the young (MODY) 5 with a whole deletion of HNF1B based on 17q12 microdeletion

We report a sporadic case of maturity-onset diabetes of the young type 5 (MODY5) with a whole-gene deletion of the hepatocyte nuclear factor-1beta (HNF1B) gene. A 44-year-old Japanese man who had been diagnosed with early-onset non-autoimmune diabetes mellitus at the age of 23 was examined. He showed multi-systemic symptoms, including a solitary congenital kidney, pancreatic hypoplasia, pancreatic exocrine dysfunction, elevation of the serum levels of liver enzymes, hypomagnesemia, and hyperuricemia. These clinical characteristics, in spite of the absence of a family history of diabetes, prompted us to make the diagnosis of maturity-onset diabetes of the young 5 (MODY 5). One allele deletion of the entire HNF1B gene revealed by multiplex ligation-dependent probe amplification (MLPA) led us to the diagnoses of 17q12 microdeletion syndrome even though there were negative chromosomal analyses with array comparative genomic hybridization (CGH). 17q12 microdeletion syndrome, which is not rare especially in sporadic cases since 17q12 is a typical hot spot for chromosomal deletion, could have complicated the clinical heterogeneity of MODY5.

Periodontal Disease May be Associated With the Occurrence of Diabetic Retinopathy: A Subgroup Analysis of The Survey of the Diabetes Coordination Notebook in Gifu

Aims A questionnaire survey of the prevalence of diabetic retinopathy was recently conducted in Japan. A subgroup analysis to examine the association of periodontal disease with diabetic retinopathy in subjects with diabetes and prediabetes was conducted.

Methods The association of the presence of periodontal disease with the occurrence of diabetic retinopathy was examined using multivariate logistic regression analysis.

Results Of 27 016 subjects who completed a survey at 217 community pharmacies, 5 572 had diabetes or prediabetes, among whom 522 and 1 421 had retinopathy or periodontal disease, respectively. Therapy duration≥10 years (OR: 2.73, 95% CI: 2.17–3.43, P<0.001), periodontal disease (OR: 2.10, 95% CI: 1.68–2.62, P<0.001) and glycated hemoglobin (HbA1c) ≥ 7.0% (OR: 1.64, 95% CI: 1.32–2.04, P<0.001) were significantly associated with the occurrence of retinopathy, while retinopathy (OR: 2.11, 95% CI: 1.69–2.63, P<0.001) and therapy duration ≥10 years (OR: 1.24, 95% CI: 1.06–1.46, P=0.007) were significantly associated with the occurrence of periodontal disease. The prevalence of retinopathy was much higher in diabetic subjects with periodontal disease than in those without it (15.1% vs. 7.8%, P<0.001). Notably, the difference of prevalence of retinopathy between subjects with and without periodontal disease was statistically significant even at HbA1c 6.0–6.9% (15.2% vs. 7.3%, P<0.01).

Conclusions These findings indicate that the target HbA1c level for diabetes patients with periodontal disease may be set lower than for those without it, and that regular dental visits should be prescribed for the management of periodontal disease and the prevention of diabetic retinopathy.

Genetic Dissection and Clinical Features of MODY6 (NEUROD1-MODY)

PURPOSE OF REVIEW

MODY6 due to mutations in the gene NEUROD1 is very rare, and details on its clinical manifestation and pathogenesis are scarce. In this review, we have summarized all reported cases of MODY6 diagnosed by genetic testing, and examined their clinical features in detail.

RECENT FINDINGS

MODY6 is a low penetrant MODY, suggesting that development of the disease is affected by genetic modifying factors, environmental factors, and/or the effects of interactions of genetic and environmental factors, as is the case with MODY5. Furthermore, while patients with MODY6 can usually achieve good glycemic control without insulin, when undiagnosed they are prone to become ketotic with chronic hyperglycemia, and microangiopathy can progress. MODY6 may also cause neurological abnormalities such as intellectual disability. MODY6 should be diagnosed early and definitively by genetic testing, so that the correct treatment can be started as soon as possible to prevent chronic hyperglycemia.

NEUROD1-deficient diabetes (MODY6): Identification of the first cases in Japanese and the clinical features

AIMS

Only a few families with neuronal differentiation 1 (NEUROD1)-deficient diabetes, currently designated as maturity-onset diabetes of the young 6 (MODY6), have been reported, but mostly in Caucasian, and no mutation has been identified by family-based screening in Japanese. Accordingly, the phenotypic details of the disease remain to be elucidated.

METHODS

We examined a total of 275 subjects having diabetes suspected to be MODY who were negative for mutations in MODY1-5 referred from 155 medical institutions throughout Japan. So as not to miss low penetrant cases, we examined non-obese Japanese patients with early-onset diabetes regardless of the presence of family history by direct sequencing of all exons and flanking regions of NEUROD1 . Large genomic rearrangements also were examined.

RESULTS

Four patients with 3 frameshift mutations and 1 missense mutation, all of which were heterozygous and 3 of which were novel, were identified. Diabetic ketosis was found occasionally in these patients even under conditions of chronic hyperglycemia, for unknown reasons. Although the capacity of early-phase insulin secretion was low in these patients, the insulin secretory capacity was relatively preserved compared to that in hepatocyte nuclear factor (HNF)1A- and HNF1B-MODY. One of the patients and 2 of their diabetic mothers were found to have some mental or neuronal abnormality.

CONCLUSIONS

This is the first report of NEUROD1 mutations in Japanese, who have a genetic background of intrinsically lower capacity of insulin secretion. NEUROD1-deficient diabetes appears to be low penetrant, and may occur in concert with other genetic factors.

Effectiveness of Sodium-Glucose Cotransporter-2 Inhibitor as an Add-on Drug to GLP-1 Receptor Agonists for Glycemic Control of a Patient with Prader-Willi Syndrome: A Case Report

INTRODUCTION

Diabetes patients with Prader-Willi syndrome (PWS) are obese because of hyperphagia; weight control by dietary modification and medicine is required for glycemic control. There are several recent reports showing the effectiveness of GLP-1 receptor agonists (GLP-1RAs) for diabetes treatment in PWS.

CASE REPORT

A 36-year-old Japanese male patient was diagnosed with PWS at 10 years of age. At age 16 years, he was diagnosed with diabetes and began to take several kinds of oral hypoglycemic agents. At age 29 years, his BMI was 39.1 kg/m² and he was referred to our department for diabetes and obesity treatment. In the present case, the HbA1c was not improved by GLP-1RAs despite a 28-kg BW reduction, which included a 9-kg loss of muscle. Apprehensive of further loss of muscle mass, basal insulin of insulin glargine was administered in addition to GLP-1RAs. Immediately after the addition of tofogliflozin, a sodium-glucose cotransporter-2 (SGLT2) inhibitor, the patient's HbA1c decreased dramatically with only about an additional 3% BW reduction. We note an improvement in our case of lipid deposition in the pancreas confirmed by abdominal CT after the improvement of HbA1c. It is unknown whether this improvement of fatty pancreas was a cause or an effect of the improved glycemic control in the present case.

CONCLUSION

This finding clearly supports the effectiveness of combining SGLT2 inhibitors with GLP-1RAs for treatment of patients with PWS and non-alcoholic fatty pancreas disease.

A first case of adrenomyeloneuropathy with mutation Y174S of the adrenoleukodystrophy gene

The patient first noticed spasticity and weakness in his legs. He was diagnosed with chronic myelogenous leukemia (CML); the symptoms were attributed to neuropathy associated with CML. By treatment with dasatinib, he achieved complete hematological remission, but his difficulty in walking was not improved. His neurological symptom worsened together with an increase in body temperature and then disappeared together with a normalized body temperature, which may be attributed to the Uhthoff's phenomenon often observed in multiple sclerosis. He later developed acute fever, vomiting and a high adrenocorticotropic hormone (ACTH) level, which was diagnosed as adrenal insufficiency. Eventually, he was diagnosed with a milder form of adrenoleukodystrophy (ALD), adrenomyeloneuropathy (AMN) by increased levels of Very Long Chain Fatty Acids (VLCFAs) and genetic testing of the ATP binding cassette subfamily D member 1 (ABCD1) gene. A missense mutation (c.521A>C, p.Tyr174Ser), previously reported to induce severe cerebral ALD, was detected in exon1. Thus, clinical manifestation of ALD is determined by interaction between the primary ABCD1 mutation and modifying genetic and environmental factors. Physicians should be aware of the differing symptoms of AMN and determine the level of VLCFAs in patients having primary adrenal insufficiency, especially those complicated with neurological dysfunction. This is the first report of an AMN patient complicated with CML.

Screening of diabetes of youth for hepatocyte nuclear factor 1 mutations: clinical phenotype of HNF1β-related maturity-onset diabetes of the young and HNF1α-related maturity-onset diabetes of the young in Japanese

AIM

To compare the prevalence and clinical features of HNF1β-related MODY and HNF1α-related MODY in Japanese.

METHODS

We enrolled 230 Japanese patients with suspected MODY and examined them for HNF1α and HNF1β mutations. We characterized the clinical features of HNF1β-related MODY (HNF1β-MODY) and HNF1α-related MODY (HNF1α-MODY).

RESULTS

Six patients had HNF1β mutations, four of which were large gene deletions and 24 patients had HNF1α mutations, which included one gene deletion. The mean fasting plasma glucose level at onset of HNF1β-MODY was considerably higher and the age of onset of HNF1β-MODY was considerably older than they were for HNF1α-MODY, while the mean BMI and C-peptide index at onset were similar. Three patients with HNF1β-MODY were found to have dorsal pancreatic agenesis and four of them had whole-gene deletion. Five of the patients with HNF1β-MODY had insulin secretion defects and were treated with insulin, and four of these did not have a parent with overt diabetes.

CONCLUSION

HNF1β-MODY may present as β-cell dysfunction in Japanese rather than as hyperinsulinaemia, which it does among European/American. This dysfunction might result from an intrinsically lower capacity for insulin secretion in Japanese. HNF1β-MODY has an older age of onset than HNF1α-MODY, which may suggest lower penetrance of the disease. In addition, HNF1β-MODY has a broad spectrum of clinical manifestations, some of which are detectable by imaging. This may be helpful in some cases for selecting HNF1β-MODY candidates for genetic testing.

Synergistic effect of α-glucosidase inhibitors and dipeptidyl peptidase 4 inhibitor treatment

Monotherapy of α‐glucosidase inhibitor (α‐GI) or dipeptidyl peptidase 4 (DPP4) inhibitor does not sufficiently minimize glucose fluctuations in the diabetic state. In the present study, we evaluated the combined effects of various of α‐GI inhibitors (acarbose, voglibose or miglitol) and sitagliptin, a DPP4 inhibitor, on blood glucose fluctuation, insulin and active glucagon‐like peptide‐1 (GLP‐1) levels after nutriment loading in mice. Miglitol and sitagliptin elicited a 47% reduction (P < 0.05) of the area under the curve of blood glucose levels for up to 2 h after maltose‐loading, a 60% reduction (P < 0.05) in the range of blood glucose fluctuation, and a 32% decrease in plasma insulin compared with the control group. All three of the combinations elicited a 2.5–4.9‐fold synergistic increase in active GLP‐1 (P < 0.05 vs control). Thus, combined treatment with the α‐GI miglitol, which more strongly inhibits the early phase of postprandial hyperglycemia, and DPP4 inhibitor yields both complementary and synergistic effects, and might represent a superior anti‐hyperglycemic therapy. (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2010.00081.x, 2011)

[Association between polymorphisms of TCF7L2 and type 2 diabetes with special reference to incretin action]

TCF7L2 is a Wnt signaling-associated transcription factor and is ubiquitously expressed. Polymorphisms in the TCF7L2 gene exhibit the strongest association with type 2 diabetes among approximately twenty susceptibility gene variants identified to date. Although the mechanisms by which TCF7L2 affects susceptibility to type 2 diabetes remain to be elucidated, several studies have shown that decreased TCF7L2 protein inhibits the insulin secretory response to oral glucose through impaired incretin action(GLP-1, GIP). In this review, we discuss studies that investigate the association between polymorphisms of TCF7L2 and the diabetic phenotype, especially in vitro beta cell function with special reference to incretin action and the response to lifestyle intervention.

Identification of minimal promoter and genetic variants of Kruppel-like factor 11 gene and association analysis with type 2 diabetes in Japanese

Genetic analysis of the KLF11 gene revealed two rare variants, A347S and T220M, segregating in families with early-onset type 2 diabetes, and one frequent polymorphic Q62R variant significantly associated with type 2 diabetes in Northern Europeans. Furthermore, it has been reported that over-expression of KLF11 has a deleterious effect on insulin promoter activity. Thus, an altered expression level of KLF11 may contribute to the occurrence of type 2 diabetes. To investigate the contribution of KLF11 to type 2 diabetes in Japanese, we surveyed the 5' flanking region of KLF11 by reporter assay and identified the minimal promoter region of the gene. The promoter region from -250 to +162 bp including five Sp1 binding sites showed basal promoter activity both in MIN6-m9 and HepG2 cells. We also examined the entire region of KLF11 to detect genetic variants. A total of 19 polymorphisms, six of which are novel, were identified, but none of them showed association with the occurrence of type 2 diabetes. Two of the identified polymorphisms, R29Q and S124F, are novel coding variants. Functional analyses of these variants were performed, and similarly reduced effects on transcriptional activities of insulin, catalase1, and the Smad7 gene were found. We conclude that variants of KLF11 are not a major factor in the occurrence of type 2 diabetes in Japanese. The promoter region of KLF11 identified in the present study should be useful in further elucidation of the transcriptional regulation mechanism of the gene and genetic analyses of type 2 diabetes.

Mutations in the small heterodimer partner gene increase morbidity risk in Japanese type 2 diabetes patients

Mutations in the small heterodimer partner gene (NR0B2; alias SHP) are associated with high birth weight and mild obesity in Japanese children. SHP mutations may also be associated with later obesity and insulin resistance syndrome that induces diabetes. To investigate this possibility, the prevalence of SHP mutations in Japanese with and without type 2 diabetes mellitus and the functional properties of the mutant proteins were evaluated. Direct sequencing of two exons and flanking sequences of SHP in 805 diabetic patients and 752 non-diabetic controls identified 15 different mutations in 44 subjects, including 6 novel mutations. Functional analyses of the mutant proteins revealed significantly reduced activity of nine of the mutations. Mutations with reduced activity were found in 19 patients (2.4%) in the diabetic group and in 6 subjects (0.8%) in the control group. The frequency difference between DM and control subjects adjusted for sex and age was statistically significant (P=0.029, odds ratio 2.67, 95% CI 1.05-6.81, 1-beta=0.91). We conclude that SHP mutations associated with mild obesity in childhood increase susceptibility to type 2 diabetes in later life in Japanese.

Case report of familial Carney complex due to novel frameshift mutation c.597del C (p.Phe200LeufsX6) in PRKAR1A

Carney complex is an autosomal dominantly inherited disease characterized by skin pigmentation, myxoma, primary pigmented nodular adrenocortical disease (PPNAD), and acromegaly. However, only a few incidences of PPNAD combined with acromegaly are observed in patients. The type 1alpha regulatory subunit of cAMP-dependent protein kinase (PRKAR1A) has been identified in patients as a causative gene for Carney complex by a positional cloning approach. Here, we report a female patient diagnosed with Cushing's syndrome and a GH-producing pituitary adenoma without otherwise evident acromegaly that could be diagnosed only by specialized endocrinological tests. Based on family history of acromegaly (mother and sister) and the fact that the combination of both diseases is very rare, genetic diagnosis involving Carney complex was considered to be appropriate. The 10 exons and flanking regions of PRKAR1A were screened for mutations by direct DNA sequencing. The patient and her mother and sister were found to have the same, novel frameshift mutation resulting from a single base deletion in exon 6 coding cAMP-binding domain A, denoted c.597delC in PRKAR1A. This single base deletion generated an immature stop codon at the sixth codon (p.Phe200LeufsX6). Even family members with the same mutation can show distinct phenotypes, suggesting that Carney complex is a multifactorial disorder comprising various genetic and environmental factors. Genetic diagnosis makes it possible to prepare more effective therapeutic strategies for patients and gene carriers and to avoid unnecessary tests for non-carriers in the family of the patient.

Replication of genome-wide association studies of type 2 diabetes susceptibility in Japan

BACKGROUND

In Europeans and populations of European origin, several groups have recently identified novel type 2 diabetes susceptibility genes, including FTO, SLC30A8, HHEX, CDKAL1, CDKN2B, and IGF2BP2, none of which were in the list of functional candidates.

OBJECTIVE AND DESIGN

The aim of this study was to replicate in a Japanese population previously identified associations of single nucleotide polymorphisms (SNPs) within 10 candidate loci with type 2 diabetes using a relatively large sample size: 1921 subjects with type 2 diabetes and 1622 normal controls.

RESULTS

A total of 15 SNPs were genotyped. Eight SNPs in five loci were found to be associated with type 2 diabetes: rs3802177 [odds ratio (OR) = 1.16 (95% confidence interval (CI) 1.05-1.27); P = 4.5 x 10(-3)] in SLC30A8; rs1111875 [OR = 1.27 (95% CI 1.14-1.40); P = 1.4 x 10(-5)] and rs7923837 [OR = 1.27 (95% CI 1.13-1.43); P = 1.0 x 10(-4)] in HHEX; rs10811661 [OR = 1.27 (95% CI 1.15-1.40); P = 1.9 x 10(-6)] in CDKN2B; rs4402960 [OR = 1.23 (95% CI 1.11-1.36); P = 8.1 x 10(-5)] and rs1470579 [OR = 1.18 (95% CI 1.07-1.31); P = 8.3 x 10(-4)] in IGF2BP2; and rs7754840 [OR = 1.28 (95% CI 1.17-1.41); P = 4.5 x 10(-7)] and rs7756992 [OR = 1.27 (95% CI 1.15-1.40); P = 9.8 x 10(-7)] in CDKAL1. The first and second strongest associations were found at variants in CDKAL1 and CDKN2B, both of which are involved in the regenerative capacity of pancreatic beta-cells.

CONCLUSION

Some of these variants represent common type 2 diabetes-susceptibility genes in both Japanese and Europeans.

Depressive state and paresthesia dramatically improved by intravenous MgSO4 in Gitelman's syndrome

A 69-year-old woman was referred to our department for evaluation of hypokalemia, which had been treated by oral potassium for more than ten years. She complained of headache, knee joint pain, sleeplessness and paresthesia in extremities and, most prominently, depression. Laboratory data suggested Gitelman's syndrome, which is caused by mutations in the gene encoding the thiazide-sensitive Na-Cl cotransporter. Direct sequencing of the gene in this patient revealed homozygous mutation R964Q in exon 25. Intravenous supplement of MgSO4 dramatically improved both the depression and the paresthesia, suggesting that hypomagnesemia played a role in the clinical manifestations.

Gadolinium-enhanced MR imaging of the liver: optimizing imaging delay for hepatic arterial and portal venous phases--a prospective randomized study in patients with chronic liver damage

PURPOSE

To investigate the optimal imaging delays for hepatic arterial and portal venous phases of gadolinium-enhanced dynamic spoiled gradient-recalled-echo magnetic resonance (MR) imaging of the liver in patients with chronic liver damage.

MATERIALS AND METHODS

MR images were obtained after intravenous bolus injection of gadopentetate dimeglumine in 100 patients with chronic liver damage. Test bolus imaging was performed to determine the aortic transit time. A 26-second spoiled gradient-recalled-echo sequence was used. Patients were randomized into four groups so that the middle of k space was acquired at 5, 10, 15, and 20 seconds for the first phase and 45, 50, 55, and 60 seconds for the second phase, respectively, from the time of arrival of contrast material in the abdominal aorta. Mean signal intensities of the liver, spleen, and abdominal aorta were measured, and images were reviewed prospectively by three radiologists in consensus. Analysis of variance, the Scheffé criterion for continuous data, and the Kruskal-Wallis test for categorical data were used for statistical evaluation.

RESULTS

Intense splenic enhancement with the moiré pattern without intense hepatic enhancement occurred at 10-15 seconds. Aortic and splenic enhancement significantly decreased from 45 to 50 seconds (P <.05). Spleen-to-liver contrast-to-noise ratio began to decrease at 20 seconds and decreased constantly over time. Qualitative results correlated well with quantitative results.

CONCLUSION

Biphasic imaging with k space centered at 10-15 and 50 seconds or later after arrival of contrast material in the abdominal aorta may be the optimal technique to obtain ideal contrast enhancement. Empirically, delays of 28-34 and 68 seconds or later after initiating contrast material injection may be effective for biphasic imaging.

Can endoscopic papillary balloon dilation really preserve sphincter of Oddi function?

BACKGROUND

Endoscopic papillary balloon dilation (EPBD) is assumed to preserve sphincter of Oddi function because it causes little trauma to the papilla. However, few studies have addressed this issue specifically. In this study, we investigated whether EPBD can preserve sphincter function, and evaluated whether or not such preservation has clinical significance.

METHODS

Seventy patients with common bile duct (CBD) stones were randomly assigned to EPBD or endoscopic sphincterotomy (EST). Sphincter of Oddi (SO) function was measured by endoscopic manometry before, one week after, and one year after treatment. Incidence of pneumobilia and later complications were compared between the two groups at one year. Series manometric data were compared within each group and between the two groups. For a more detailed analysis of the cumulative incidence of later complications, retrospective cohorts were added to the study groups, giving a total number of 235 patients in the EPBD group and 126 in the EST group.

RESULTS

Baseline characteristics did not differ significantly between the 35 EPBD and 35 EST patients. CBD stones were discharged successfully in all cases. CBD pressure, SO basal and peak pressures, and contraction frequency decreased significantly at one week in both groups. The damage was more severe in the EST group, and SO contraction completely disappeared in 23 patients in this group. The incidence of pneumobilia was significantly lower in the EPBD group than in the EST group (p<0.01) whereas CBD stones recurred and cholecystitis appeared at a similar rate in both groups at one year. A complete series of manometric data up to one year was obtained in 55 patients; 28 in the post-EPBD and 27 in post-EST groups. In the post-EPBD group, SO basal and peak pressures significantly recovered at one year compared with data at one week but these measures still remained significantly lower than those before EPBD (p< 0.01). In the post-EST group, SO contraction did not recover even after one year. A Kaplan-Meier analysis of 235 EPBD and 126 EST patients for a median follow up of 37 months revealed significantly lower incidences of biliary complications such as recurrent CBD stones and cholangitis, and cholecystitis in the EPBD group than in the EST group (p<0.05). The risk of pneumobilia was also significantly lower in the EPBD group (p<0.01).

CONCLUSIONS

Preservation of papillary function after EPBD was not complete but remained somewhat reduced. However, preservation was more successful with EPBD than with EST. Such preservation may be clinically beneficial for the prevention of later complications.

[Usefulness of dynamic MR mammography for diagnosis of axillary lymph node status in breast cancer patient]

A retrospective study was performed to evaluate whether dynamic MR imaging is useful for the diagnosis of axillary lymph node metastases from breast cancer. Thirty-five patients with breast cancer were scanned and 147 lymph nodes were detected and compared with pathological nodal status. The parameters were the long axis dimension, the short axis dimension, the long-to-short axis (L/S) ratio, the shape, the contrast enhancement ratio (CER), the CER of lymph node-to-primary tumor (L/P) ratio. All parameters had significant differences between metastatic and normal nodes and there was a positive correlation between the CER of primary breast tumors and metastatic nodes. Multivariate analysis identified three parameters: the shape, the CER (1st phase), the L/P ratio (1st phase). ROC analysis revealed the shape and CER are superior in diagnostic performance to L/P ratio. If the shape and CER (1st phase) 60% and above are employed as criteria, the sensitivity, the specificity, the accuracy and the positive and negative predictive value were 86.0%, 78.4%, 81.0%, 67.2% and 91.6%, respectively. This method gives us useful information about the evaluation of axillary lymph node status preoperatively.

Inflammatory pseudotumor of the liver with primary sclerosing cholangitis

Inflammatory pseudotumor (IPT) of the liver is a rare benign variant of hepatic masses, and its exact etiology has not been elucidated. We report a case of IPT associated with primary sclerosing cholangitis (PSC). The patient was a 50-year-old man admitted to our hospital because of jaundice. Abdominal ultrasonography (US) and computed tomography showed multiple dilations of the intrahepatic bile ducts and multiple masses in the liver. On magnetic resonance imaging, the masses were slightly hypointense on T1-weighted images and slightly hyperintense on T2-weighted images. On T1-weighted images after the bolus infusion of Gd chelate, the masses had no contrast enhancement, and they were hypointense in the arterial phase and portal venous phase. However, they were slightly enhanced and became almost isointense relative to the surrounding normal liver parenchyma in the delayed phase. Endoscopic retrograde cholangiography demonstrated multiple irregular strictures and dilations of the intrahepatic bile ducts. Angiography demonstrated no abnormal findings, but, interestingly, subsequent dynamic CO2-enhanced US showed a strongly hyperechoic string, indicating that an artery had penetrated through the hypoechoic mass. A US-guided percutaneous needle biopsy revealed that the lesions were morphologically comparable to IPT. After cholangiography and microscopic analysis of the tumor, the final diagnosis was determined to be IPT of the liver with PSC. A number of previous reports have suggested a possible relationship between IPT and PSC, based on pathological findings. This report confirmed, based on clinical findings, that PSC is one of the causes of hepatic IPT.

Appearance of sodium dodecyl sulfate-stable amyloid beta-protein (Abeta) dimer in the cortex during aging

We previously noted that some aged human cortical specimens containing very low or negligible levels of amyloid beta-protein (As) by enzyme immunoassay (EIA) provided prominent signals at 6 approximately 8 kd on the Western blot, probably representing sodium dodecyl sulfate (SDS)-stable Abeta dimer. Re-examination of the specificity of the EIA revealed that BAN50- and BNT77-based EIA, most commonly used for the quantitation of Abeta, capture SDS-dissociable Abeta but not SDS-stable Abeta dimer. Thus, all cortical specimens in which the levels of Abeta were below the detection limits of EIA were subjected to Western blot analysis. A fraction of such specimens contained SDS-stable dimer at 6 approximately 8 kd, but not SDS-dissociable A(beta) monomer at approximately 4 kd, as judged from the blot. This A(beta) dimer is unlikely to be generated after death, because (i) specimens with very short postmortem delay contained the A(beta) dimer, and (ii) until 12 hours postmortem, such SDS-stable A(beta) dimer is detected only faintly in PDAPP transgenic mice. The presence of A(beta) dimer in the cortex may characterize the accumulation of A(beta) in the human brain, which takes much longer than that in PDAPP transgenic mice.

Endoscopic papillary balloon dilatation for common bile duct stones: efficacy of combination with extracorporeal shockwave lithotripsy for large stones

BACKGROUND

Endoscopic papillary balloon dilatation (EPBD) is generally considered a safe and effective technique for removal of common bile duct (CBD) stones. However, some reports have prompted concern about the risk of pancreatitis following the procedure, and it seems to be more difficult and to require adjunctive procedures more frequently in patients with large stones.

AIMS

To analyse the factors influencing pancreatitis after the procedure, and to examine which is the more suitable adjunct for treating large stones, mechanical lithotripsy (ML) or extracorporeal shockwave lithotripsy (ESWL).

PATIENTS AND METHODS

EPBD was performed in 92 patients, including 40 with large stones (> or = 12 mm). These 40 patients were randomly assigned to two groups receiving ML or ESWL to fragment stones (20 patients each).

RESULTS

Complete ductal clearance was obtained in all 92 patients. Significant elevation of the serum amylase level compared with the prior value (> 300 IU/l) was observed in 26 (28%), and eight (8.7%) developed clinical pancreatitis. To assess the influence of various factors on the amylase level, multivariate analysis was used. The number of stones and the time required for treatment had a significant influence on the incidence of increased amylase level (P < 0.05), and ML also significantly increased it (P < 0.05). On the other hand, the amylase level remained low in the ESWL group. ML caused elevation of amylase level in 11 patients (55%), while three (15%) had elevation after ESWL.

CONCLUSIONS

In patients with multiple stones, elevation of the amylase level is more frequent. This seems to be because repeated cannulation and much time is required for treatment. In patients with large stones, the rate was also high if ML was used, but was low when ESWL was used. ESWL may reduce the incidence of pancreatitis.

Hepatodiaphragmatic portosystemic shunt in cirrhosis

A case of an unusual form of hepatodiaphragmatic portosystemic shunt arising from the periphery of left posterosuperior portal vein branch, running beneath the inferior aspect of left hemidiaphragm and draining into the left lateral abdominal wall is demonstrated and assessed with digital subtraction portography, maximum-intensity-projection images reconstructed from helical CT during arterial portography and pulsed Doppler sonography with flow velocity measurement. This is a reported case of this unusual intrahepatic portosystemic shunt and discussion on the utility of current radiological techniques.

Nondiseased portal perfusion defects adjacent to the right ribs shown on helical CT during arterial portography

OBJECTIVE

The purpose of our study was to assess the frequency and imaging characteristics of nonpathologic portal perfusion defects in subcapsular liver parenchyma adjacent to the right ribs as seen on CT hepatic arteriography combined with helical CT during arterial portography (CTAP).

MATERIALS AND METHODS

From January 1994 to June 1997, helical CTAP and CT hepatic arteriography were performed in 94 patients with suspected malignant hepatic tumors. The patient group comprised 66 men and 28 women ranging from 37 to 83 years old (mean, 64 years old). Three radiologists retrospectively reviewed the images obtained by CTAP to evaluate portal perfusion defects adjacent to the right ribs for location, shape, size, and correlation with findings seen on CT hepatic arteriography.

RESULTS

We identified 16 nonpathologic portal perfusion defects adjacent to the right eighth (n = 1), ninth (n = 12), and tenth (n = 3) ribs in 12 (13%) of 94 patients. The shapes of the 16 defects were circular (n = 1), oval (n = 7), wedge (n = 3), and irregular (n = 5). The defects were 10-30 mm in diameter (mean, 16.9 mm). In four (25%) of 16 locations, CT hepatic arteriography showed poorly identified, homogeneous, irregularly shaped areas of contrast enhancement corresponding to the defects seen on CTAP. The portal perfusion defects were proven to be nonpathologic on definitive surgery in four patients and on follow-up radiography in eight patients.

CONCLUSION

Helical CTAP may show nonpathologic portal perfusion defects adjacent to the right ribs. Most defects did not appear circular but rather were oval, irregular, or wedge-shaped. CT hepatic arteriography infrequently showed corresponding findings. Radiologists should recognize this potential pitfall when interpreting images obtained by helical CTAP.

Nonpathological focal enhancements on spiral CT hepatic angiography

BACKGROUND

To assess the frequency and characteristics of nonpathological focal enhancements seen on spiral computed tomographic (CT) hepatic angiography (CTA).

METHODS

Spiral CTA and spiral CT arterial portography (CTAP) were performed in 31 patients with suspected liver malignancy prior to potential liver resection. The CTA images were retrospectively reviewed for focal enhancements by two radiologists. After determining nonpathological focal enhancements on CTA images based on the other radiographic tests, surgical exploration including intraoperative sonography, follow-up imagings, the frequency, size, site, and shape of nonpathological focal enhancements with CTA were assessed.

RESULTS

Thirty-six nonpathological focal enhancements with CTA from 4 to 23 (mean = 11. 4) mm were seen in 14 (45.2%) of 31 patients. Thirteen (36.1%) of 36 nonpathological focal enhancements with CTA were not depicted with CTAP. Nonpathological focal enhancements with CTA were frequent in Couinaud segments III (27.8%), V (22.2%), and VI (19.4%). Twenty-three (63.9%) of 36 nonpathological focal enhancements were located in the edge of the liver. Shapes of 36 nonpathological focal enhancements with CTA included circular (n = 16), worm (n = 7), irregular (n = 6), dot (n = 6), and wedge (n = 1).

CONCLUSION

In nearly half of patients, spiral CTA shows various shapes of small nonpathological focal enhancements more frequently in the liver edge.