ABSTRACT
BACKGROUND: Acute kidney injury (AKI) is a disease that negatively affects patient prognosis and requires early diagnosis and treatment. Biomarkers that predict AKI are needed for early diagnosis of this disease. METHODS: We compared the AKI group and the non-AKI group in patients who were admitted to our critical care intensive care unit (ICU) and conducted a comparative study focusing on urinary neutrophil gelatinase-associated lipocalin (U-NGAL) and serum procalcitonin (PCT). RESULTS: Seventy-one out of 106 ICU inpatients were diagnosed with AKI in accordance with the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Among the patients who were diagnosed with AKI stages 1 to 3, 94.4% of all patients reached the maximum stage by day 5 after admission. Comparing the non-AKI group and AKI stage 1 to 3 on days 1 to 3 after admission, U-NGAL and PCT levels in the stage 3 group were significantly higher than those in the non-AKI group. Additionally, in receiver operating characteristic curve (ROC) analysis on days 1-3 after admission, U-NGAL and PCT levels can be used as biomarkers for the diagnosis of AKI, and in particular, AKI stage 3 can be predicted and diagnosed with high accuracy. U-NGAL and PCT levels were also significantly higher in AKI due to sepsis and acute pancreatitis and due to sepsis, respectively. CONCLUSIONS: Measuring U-NGAL and PCT levels as biomarkers for AKI may further improve the accuracy of AKI diagnosis in critical care ICU.
Subject(s)
Acute Kidney Injury/blood , Acute Kidney Injury/urine , Critical Care , Hospitalization , Intensive Care Units , Lipocalin-2/urine , Procalcitonin/blood , Acute Kidney Injury/diagnosis , Aged , Aged, 80 and over , Biomarkers/metabolism , Creatinine/blood , Female , Humans , Length of Stay , Male , Middle Aged , Prognosis , ROC Curve , Time FactorsABSTRACT
Segmental progeroid syndromes with lipodystrophy are extremely rare, heterogeneous, and complex multi-system disorders that are characterized by phenotypic features of premature aging affecting various tissues and organs. In this study, we present a "sporadic/isolated" Japanese woman who was ultimately diagnosed with mandibular hypoplasia, deafness, progeroid features, and progressive lipodystrophy (MDPL) syndrome (MIM #615381) using whole exome sequencing analysis. She had been suspected as having atypical Werner syndrome and/or progeroid syndrome based on observations spanning a 30-year period; however, repeated genetic testing by Sanger sequencing did not identify any causative mutation related to various subtypes of congenital partial lipodystrophy (CPLD) and/or mandibular dysplasia with lipodystrophy (MAD). Recently, MDPL syndrome has been described as a new entity showing progressive lipodystrophy. Furthermore, polymerase delta 1 (POLD1) gene mutations on chromosome 19 have been identified in patients with MDPL syndrome. To date, 21 cases with POLD1-related MDPL syndrome have been reported worldwide, albeit almost entirely of European origin. Here, we identified a de novo mutation in exon 15 (p.Ser605del) of the POLD1 gene in a Japanese case by whole exome sequencing. To the best of our knowledge, this is the first identified case of MDPL syndrome in Japan. Our results provide further evidence that mutations in POLD1 are responsible for MDPL syndrome and serve as a common genetic determinant across different ethnicities.
Subject(s)
Abnormalities, Multiple/diagnosis , DNA Polymerase III/genetics , Deafness/complications , Lipodystrophy/complications , Micrognathism/complications , Progeria/complications , Abnormalities, Multiple/genetics , Deafness/congenital , Deafness/diagnosis , Deafness/genetics , Delayed Diagnosis , Diagnosis, Differential , Female , Humans , Japan , Lipodystrophy/congenital , Lipodystrophy/diagnosis , Lipodystrophy/genetics , Mandible/abnormalities , Micrognathism/diagnosis , Micrognathism/genetics , Middle Aged , Mutation , Progeria/diagnosis , Progeria/genetics , SyndromeABSTRACT
Immunosuppressive therapy or chemotherapy-induced hepatitis B virus (HBV) reactivation can cause se- vere hepatitis in inactive HBV carriers or patients with resolved infection. We surveyed patients with measured HBV DNA levels from 2009 to 2014, and analyzed the clinical profile, treatment regimen and the period leading up to HBV reactivation from therapy start date. Between 2009 and 2014, the total number of HBV viral load measurements taken in our hospital increased 2.3-fold. HBV DNA measurements requested by the Department of Gastroenterology and Hepatology ac- counted for 82.8% of the total in 2009; however, this was reduced to 38.0% in 2014, as the number of re- quests from other departments increased. We referred all patients with reactivated HBV infection to a hepatology specialist. The total number of reactivation patients in 2014 was increased to about 8.2 times that observed in 2009. Nineteen males and 24 females were included in our cohort, and the average age was 69±10.1 years old. Thirty-two patients had previously received chemotherapy, and seven had undergone immunosuppressive treatment. A delay of more than 12 months from commencement of therapy to HBV reactivation was observed in 49% of patients. These results indicate that it is very important to monitor HBV DNA and properly enforce pre-treatment examinations according to the guidelines for prevention and treatment of HBV during immunosuppressive therapy. [Original].
Subject(s)
Hepatitis B virus/physiology , Hepatitis B/virology , Virus Activation , Adult , Aged , DNA, Viral/analysis , Female , Hepatitis B virus/genetics , Hospitals, University , Humans , Middle AgedABSTRACT
OBJECTIVES: Anti-cancer and immunosuppressive drugs often induce hepatitis B virus (HBV) reactivation, resulting in lethal hepatitis in the worst cases. It is to elucidate the clinical characteristics of the patients in our hospital, who underwent HBV-related examinations to help prevent HBV-associated hepatitis by reactivation during the two-year period after the announcement of new guidelines by the Ministry of Health, Labour and Welfare of Japan in January 2009. STUDY DESIGN: We enrolled 811 patients who were examined for HBs antigen, anti-HBc antibody, anti-HBs antibody and HBV DNA regarding HBV reactivation. RESULTS: The underlying diseases were hematological malignancies, followed by various other cancers, rheumatoid arthritis, Crohn's disease, and so on. The patients in their 60s showed the peak in the age distribution. The positive ratio of anti-HBc antibody was higher over the age of 40. The rate of reactivation was 7.7% in HBV carriers and 2.0% in the HBV-resolved patients. HBV reactivation occurred in two HBV carriers and four HBV-resolved patients. The three patients, showing hepatitis were two HBV carriers and one HBV-resolved patient without monitoring of HBV DNA, because their therapies started before announcement of the guidelines. In other three patients with reactivation from HBV-resolved infections, HBV DNA returned under detection by immediate administration of entecavir without following hepatitis. CONCLUSION: The patients at high risk of HBV reactivation were prevented from HBV-related hepatitis only by following the guideline. The screening for such patients and monitoring HBV DNA in the guideline are requisite to prevent HBV-related hepatitis.
Subject(s)
Antineoplastic Agents/adverse effects , Chemistry, Clinical , Hepatitis B virus/physiology , Hepatitis B/diagnosis , Hepatitis B/prevention & control , Hospital Departments , Immunosuppressive Agents/adverse effects , Virus Activation , Adult , Aged , Antiviral Agents/administration & dosage , Biomarkers/analysis , DNA, Viral/analysis , Female , Guanine/administration & dosage , Guanine/analogs & derivatives , Hepatitis B/virology , Hepatitis B Antibodies/analysis , Hepatitis B Surface Antigens/analysis , Hepatitis B virus/genetics , Hepatitis B virus/immunology , Humans , Male , Middle Aged , Monitoring, Physiologic , Practice Guidelines as TopicABSTRACT
Procalcitonin (PCT) is a frequently used marker for bacterial sepsis. The present study was aimed to assess the usefulness of PCT measurement in patient with sepsis. We studied the relationship between serum PCT level and blood culture in clinical 209 cases admitted from January 2010 through June 2010. We compared PCT level with blood culture results and other clinical data, and diagnosis such as sepsis and systemic inflammatory response syndrome (SIRS) were obtained from the medical records. In the case of patients with positive blood cultures and PCT < 0.5 ng/mL, the false- positive blood culture was suspected. The possibility of bacteremia was high when PCT level was more than 0.5 ng/mL. Patients with PCT ≥ 2 ng/mL had significant correlation with the presence of sepsis. The PCT measurement could be performed and reported rapidly and provided valuable information before availability of culture results. In this study, we found that the PCT would be a useful biomarker for confirming and ruling out sepsis.
Subject(s)
Bacteremia/diagnosis , Calcitonin/blood , Protein Precursors/blood , Sepsis/diagnosis , Adult , Aged , Aged, 80 and over , Biomarkers/blood , Calcitonin Gene-Related Peptide , Diagnosis, Differential , Female , Humans , Male , Middle Aged , Young AdultABSTRACT
We investigated the effects of specimen storage conditions on the analysis of the coagulation molecular markers, soluble fibrin (SF), thrombin-antithrombin complex (TAT), thrombomodulin (TM) and tissue plasminogen activator inhibitor-1 complex (total PAI-1: tPAI). Marker levels were measured using a STACIA automatic coagulation analyzer. Among these four markers in blood from healthy subjects, only tPAI increased gradually with time, and the differences were especially marked when blood samples were stored at room temperature. Patient blood samples were stored for 4 hours under three different conditions: whole blood storage on ice, storage on ice after centrifugation, and refrigerated storage after centrifugation. Analytical results were compared between the three sets of samples. There were no significant differences in TAT or TM after 4 hours' storage under the different conditions. However, SF was decreased in several samples. In 11 of 14 samples with >20 microg/ml SF, SF levels were reduced by >10 microg/ml when whole blood without centrifugation was stored on ice. tPAI levels increased slightly after storage for 4 hours under all three conditions. These results suggest that centrifugation followed by refrigeration is the optimal storage method for blood samples when all four markers are to be measured simultaneously in the same sample.
Subject(s)
Automation, Laboratory/instrumentation , Blood Coagulation Tests/instrumentation , Specimen Handling/methods , Antithrombin III , Biomarkers/blood , Fibrin/analysis , Humans , Peptide Hydrolases/blood , Plasminogen Activator Inhibitor 1/blood , Temperature , Thrombomodulin/blood , Time FactorsABSTRACT
The Hepatitis B virus (HBV) reactivation is defined as proliferation of HBV and hepatitis flare after medication of anti-cancer drugs and/or immunosuppressant drugs in inactive HBV carriers or patients with past illness by HBV infection. In January 2009, the guideline for prevention of immunosuppressive or chemotherapy-induced reactivation of HBV infection was established by Japanese study groups of the Ministry of Health, Labour and Welfare. We then surveyed and analyzed order numbers of the tests of HBV DNA and anti-HBc, the rate of positive results and the department of the doctors who ordered those tests, the patient ages and clinical profiles and the purpose of the tests, from 2008 to 2009 before and after announcement of the guideline. The total numbers of tests of HBV DNA were 942 in 2008 and 1350 in 2009, and those of anti-HBc were 430 in 2008 and 904 in 2009. The percentage of the orders for anti-HBc from doctors in department of gastroenterology and medicine was 71.4% in 2008 and decreased to 53.4% in 2009, instead those of hematology and oncology, pulmonary surgery and gynecology increased remarkably. The positive rates of anti-HBc increased among the patients over age 40, especially it was more than 40% over age 50. The number of the tests for the follow-up after immunosuppressive or chemotherapy increased over 4 folds. This report made clear the actual situation of screenings for the HBV reactivation by analyses of the bases in the orders and the results of the virus tests in our hospital.
Subject(s)
DNA, Viral/analysis , Hepatitis B Antibodies/analysis , Hepatitis B virus/physiology , Hepatitis B/diagnosis , Hepatitis B/virology , Hospitals, University , Virus Activation , Adolescent , Adult , Aged , Aged, 80 and over , Antineoplastic Agents/adverse effects , Biomarkers/analysis , Child , Female , Hepatitis B Core Antigens/immunology , Hepatitis B virus/drug effects , Hepatitis B virus/genetics , Humans , Immunosuppressive Agents/adverse effects , Japan , Male , Middle Aged , Young AdultABSTRACT
Serum profiles of lipids and/or liver enzymes are established markers for the estimation of insulin resistance and diabetic risk in the non-diabetic middle-aged population. To identify prediabetic markers in young subjects, 110 young male subjects (20-29 years of age) with normal glucose tolerance (NGT) were divided into two groups by median body mass index (BMI), <22.18 (n=55) and ≥22.18 (n=55) kg/m(2). Indices of insulin sensitivity including HOMA-IR and ISI composite, indices of ß-cell function including HOMA-ß, insulinogenic index (ΔI(30)/ΔG(30)) and ΔI(30)/ΔG(30)/ HOMA-IR were calculated. Statistical associations between these parameters and the serum lipid profiles and liver function were evaluated. Alanine aminotransferase (ALT), γ-glutamyltransferase (GGT), total cholesterol (TC) and triglyceride (TG) levels were inversely correlated with the ISI composite among individuals with BMI ≥22.18 kg/m(2) but not those with BMI <22.18 kg/m(2). Multivariate regression analysis revealed that, in Group N, the plasma glucose levels at 60 min (PG(60)) were inversely correlated with the ISI composite and the insulinogenic index, and were positively correlated with the GGT, TC and TG levels. On the other hand, in Group L, PG(60) was correlated with the insulinogenic index, TC and TG levels. In conclusion, elevated levels of GGT, TC and TG are good clinical markers to predict diabetic risks, even in young NGT males. Of these, GGT was the most strongly related factor among subjects with relatively high BMI.
Subject(s)
Cholesterol/blood , Prediabetic State/blood , Triglycerides/blood , gamma-Glutamyltransferase/blood , Adult , Alanine Transaminase/blood , Biomarkers/blood , Blood Glucose/metabolism , Humans , Insulin Resistance/physiology , Insulin-Secreting Cells/metabolism , Japan , Male , Prediabetic State/diagnosis , Young AdultABSTRACT
We presented a case, who showed extremely high activity of lactate dehydogenase (LD) and confirmed the presence of the LD linked immunoglobulin in her serum. The maximum activity of LD was 6830 IU/L, and the electrophoretic pattern of LD isozymes showed the broad spectrum from isozyme LD2 to LD5. Analysis by counter immuno electrophoresis revealed that immunogloblin was attached to the M subunit of LD and its subtype was an IgG, lambda-chain. The cause, which produced the complex, might be thought to be the side effects by tiapride administrated for her mild dementia. After discontinuance of this drug, the LD activity in serum had gradually reduced. The serum creatinine also increased gradually after administration of tiapride, and did not reverse to normal level by discontinuance of it. The patient died from acute renal failure, which aggravated from sporadic urinary tract infection. It was suggested that her basal renal dysfunction might be due to the LD IgG complexes. We propose a rapid disruption of suspicious drug for the course of the production of LD linked immunoglobulin, because very high titer of these complexes might suffer irreversible damage to the kidney, which chance to become acute renal failure.
Subject(s)
Antipsychotic Agents/adverse effects , Depressive Disorder, Major/drug therapy , Immunoglobulin G/blood , Immunoglobulin lambda-Chains/blood , L-Lactate Dehydrogenase/blood , Tiapamil Hydrochloride/adverse effects , Acute Kidney Injury/etiology , Aged , Depressive Disorder, Major/blood , Fatal Outcome , Female , Humans , Isoenzymes/bloodABSTRACT
The prevalence of impaired glucose tolerance and type 2 diabetes increases with age. However, controversial results have been reported in regard to which has a greater influence on the deterioration of glucose tolerance with age, namely impaired insulin sensitivity or impaired insulin secretion. The conflicting results may arise mainly from differences in the evaluation of insulin secretion and insulin sensitivity, and from differences in the physical composition and the ethnicity of the study subjects. We therefore selected Japanese subjects, between 20 and 80 years of age, with normal glucose tolerance (NGT) and with a body mass index (BMI) below 25.0 kg/m2, and then examined the subject's insulin sensitivity based on the indices of a homeostasis model assessment-insulin resistance index (HOMA-IR) and ISI composite (ISI), and beta-cell function by these of HOMA-beta, AUC I/G(0-120), an insulinogenic index (deltaI30/deltaG30), and then (deltaI30/deltaG30)/HOMA-IR derived from a 75 g-oral glucose tolerance test (OGTT). The subjects were divided into the six subgroups according to sex and age, below age 30, between ages 30 and 49, and equal to and over age 50. Both HOMA-IR and the ISI showed no differences across the range of age and sex. HOMA-beta decreased with age, and AUC I/G(0-120) decreased in the elderly. No change was observed in deltaI30/deltaG30 across the age range in men, however deltaI30/deltaG30/HOMA-IR, the index of the early phase insulin secretion adjusted for insulin sensitivity, decreased with age in both men and women. These data indicated that aging itself had no effect on insulin sensitivity, while insulin secretion in both the early and late phase during the OGTT deteriorated with age even within the NGT subjects.
Subject(s)
Aging/physiology , Insulin Resistance/physiology , Insulin/metabolism , Adult , Aged , Aged, 80 and over , Female , Glucose Tolerance Test , Humans , Insulin Secretion , Male , Middle AgedABSTRACT
In order to support a faster and more informative clinical practice, we established the criteria for panic (critical) values regarding the blood concentrations of glucose, Na, K, Ca, inorganic phosphate (IP), Hb and number of platelets, and also created a system to report these values directly to the doctors in charge. We initiated this system in September 2003. In order to evaluate the availability of this system, we analyzed the clinical data during a one year period, based on the findings of patients showing panic values, mainly concerning the disease states and the correspondences by the doctors who were directly informed. We also carried out questionnaire surveys about the panic values and the new system for all of the doctors in our hospital (recovery rate: 84.3%). The total number of panic values reported was 113 and the mean percentage of the number of ordered examinations was 0.019%. After the report, 79 cases (69.9%) were examined again or treated, while 34 cases (30.1%) had already been treated or watched carefully at the time of the report. Malignant diseases were the main causes of increased panic values (38 cases), especially in the Na, K and blood glucose of patients. The next disease state, which appeared to demonstrate high rates, was chronic renal failure (16 cases), in the low K, high Ca, and low IP patients. Most of the cases of low Hb were caused from bleeding of the gastro-intestinal tract, with malignancies next. A blood infusion was performed for all of the cases with low Hb except for one. As a result of the questionnaire survey among the staff doctors, we confirmed that this system did indeed work efficiently, and 88% of the doctors who answered the questionnaires, were satisfied with the system. In conclusion, we established a new system, which made it possible for panic values to be directly reported to the doctor in charge and this system was then evaluated for its clinical usefulness.
Subject(s)
Emergencies , Hospital Communication Systems/standards , Laboratories, Hospital/organization & administration , Japan , Surveys and QuestionnairesABSTRACT
The unique clinical manifestations of congenital partial lipodystrophy are herein reported due to its rarity.
Subject(s)
Lipodystrophy/complications , Lipodystrophy/diagnosis , Abnormalities, Multiple/diagnosis , Adult , Dwarfism/complications , Female , Growth Charts , Hearing Loss, Sensorineural/complications , Humans , Lipodystrophy/congenital , Lipodystrophy/pathology , Mandible/abnormalities , Mandible/pathologyABSTRACT
The clinical phenotypes of patients with Bartter syndrome type III sometimes closely resemble those of Gitelman syndrome. We report a patient with mild, adult-onset symptoms, such as muscular weakness and fatigue, who showed hypokalemic metabolic alkalosis, elevated renin-aldosterone levels with normal blood pressure, hypocalciuria and hypomagnesemia. She was also suffering from chondrocalcinosis. A diuretic test with furosemide and thiazide showed a good response to furosemide, but little response to thiazide. Although the clinical findings and diuretic tests predicted that the patient had Gitelman syndrome, genetic analysis found no mutation in SLC12A3. However, a novel missense mutation, p.L647F in CLCNKB, which is located in the CBS domain at the C-terminus of ClC-Kb, was discovered. Therefore, gene analyses of CLCNKB and SLC12A3 might be necessary to elucidate the precise etiology of the salt-losing tubulopathies regardless of the results of diuretic tests.
ABSTRACT
BACKGROUND: Insulin analogs are often used to treat patients with diabetes. We evaluated the cross-reactivities of anti-insulin antibodies in two insulin immunoassay kits (Architect and ECLusys) against recombinant human insulin and insulin analogs, and measured insulin concentrations in the serum of the diabetic patients treated with only insulin lispro. METHODS: Ten-fold dilutions of recombinant human insulins and insulin analogs were measured using Architect and ECLusys kits. The serum samples of 4 type 2 diabetic patients at fasting, and several time points after breakfast (25 kcal/kg) following subcutaneous injection of insulin lispro were measured by Architect, ECLusys and LISPro RIA kit. RESULTS: The ECLusys kit could detect human insulin but not insulin analogs. The Architect kit detected human insulin and insulin analogs with similar recovery ratios. The difference in serum insulin concentrations measured by Architect and ECLusys assays reflected the concentration measured by LISPro insulin kit in the patients. The differences in the AUC between Architect and ECLusys assays were significantly correlated with the AUC for LISPro assay (p<0.01). CONCLUSIONS: By exploiting the different cross-reactivities of anti-insulin antibodies to insulin analogs, it may be possible to measure the endogenous and exogenous insulin concentrations in diabetic patients treated with insulin analogs.
Subject(s)
Antibody Specificity , Diabetes Mellitus, Type 2/drug therapy , Hypoglycemic Agents/analysis , Insulin Antibodies/immunology , Insulin Lispro/analysis , Insulin/analysis , Aged , Area Under Curve , Blood Glucose/analysis , Cross Reactions , Diabetes Mellitus, Type 2/metabolism , Fasting , Female , Humans , Hypoglycemic Agents/administration & dosage , Immunoassay , Injections, Subcutaneous , Insulin/biosynthesis , Insulin Antibodies/chemistry , Insulin Lispro/administration & dosage , Male , Middle Aged , Recombinant Proteins/administration & dosage , Recombinant Proteins/analysis , Sensitivity and SpecificityABSTRACT
SUMMARY: The purpose of the present study was to elucidate the role of obesity in both early- and late-phase insulin secretion during an oral glucose tolerance test (OGTT) performed with 75 g glucose in Japanese subjects. This was performed using indices of ß-cell function adjusted for insulin sensitivity. Of 155 subjects assessed, 68 had normal glucose tolerance (NGT) and 87 had impaired glucose tolerance (IGT). We used the homeostasis model assessment-insulin resistance (HOMA-IR) index as an indicator of insulin sensitivity. As indicators of ß-cell function, we used the HOMA-ß index, an insulinogenic index (ΔI30/ΔG30), and ΔAUC I/G(0-120), which were obtained in the OGTT. We then reevaluated the results after adjusting the ß-cell function for insulin sensitivity ([ΔI30/ΔG30]/HOMA-IR index and [ΔAUC I/G(0-120)]/HOMA-IR index). ß-Cell function was observed to reduce as the glucose tolerance deteriorated from NGT to IGT. However, when the effects of obesity were considered, the obese subjects with NGT already showed a decline in the (ΔAUC I/G(0-120))/HOMA-IR index value when compared with the nonobese subjects with NGT, despite the fact these subjects did not differ with regard to (ΔI30/ΔG30)/HOMA-IR index. As the glucose tolerance deteriorated to IGT, both (ΔI30/ΔG30)/HOMA-IR index and (ΔAUC I/G(0-120))/HOMA-IR index decreased to an identical extent in both subgroups. These data indicate that obesity causes a decrease in insulin secretion, especially during the late phase following a glucose load, even if the glucose tolerance remains normal.:
ABSTRACT
OBJECTIVE: Persistent hyperinsulinaemic hypoglycaemia of infancy (PHHI) is a disorder of glucose metabolism that is characterized by dysregulated secretion of insulin from pancreatic beta-cells. This disease has been reported to be associated with mutations of the sulfonylurea receptor SUR1 (ABCC8) or the inward-rectifying potassium channel Kir6.2 (KCNJ11), which are two subunits of the pancreatic beta-cell ATP-sensitive potassium channel. PATIENTS AND METHODS: In 14 Japanese PHHI patients, all exons of SUR1 and Kir6.2 genes were analysed by polymerase chain reaction (PCR) and direct sequencing. Four patients responded to diazoxide, and nine patients underwent a subtotal pancreatectomy. Histologically, seven patients were diagnosed to have a focal form and two a diffuse form of the disease. RESULTS: We found nine novel mutations in the SUR1 gene and two in the Kir6.2 gene. In the SUR1 gene mutations, three were nonsense mutations (Y512X, Y1354X and G1469X), one was a one-base deletion in exon 7, and two were missense mutations in the nucleotide-binding domain 2 (K1385Q, R1487K). The other three mutations occurred in introns 14, 29 and 36, which might cause aberrant splicing of RNA. Two siblings in one family were heterozygotes for a missense mutation, K1385Q, which was maternally inherited. In Kir6.2 gene screening, one patient was found to be a compound heterozygote of a missense mutation (R34H) and a one-base deletion (C344fs/ter). CONCLUSION: The novel mutations reported here could be pathological candidates for PHHI in Japan. They also reveal that SUR1 and Kir6.2 mutations in the Japanese population exhibit heterogeneity and that they occurred at a frequency similar to other genetic populations.
Subject(s)
Congenital Hyperinsulinism/genetics , Islets of Langerhans/enzymology , Mutation , Potassium Channels/genetics , ATP-Binding Cassette Transporters/genetics , Adenosine Triphosphate/metabolism , Asian People , Cell Membrane/metabolism , Congenital Hyperinsulinism/metabolism , Genetic Markers , Genotype , Heterozygote , Humans , Infant, Newborn , Japan , Mutation, Missense , Pedigree , Point Mutation , Polymorphism, Single-Stranded Conformational , Potassium Channels, Inwardly Rectifying/genetics , Receptors, Drug/genetics , Sulfonylurea ReceptorsABSTRACT
BACKGROUND: A 95% pancreatectomy has become the mainstay of surgical therapy for patients with persistent hyperinsulinemic hypoglycemia of infancy (PHHI) who did not respond to medical therapy. However, a high incidence of diabetes recently has been reported after a 95% pancreatectomy. Mutations of the SUR1 (sulfonylurea receptor) or Kir 6.2 (inwardly rectifying potassium channel) genes also have been detected in some patients with nesidioblastosis. METHODS: Six infants underwent a subtotal pancreatectomy (about 80%) for the initial surgical treatment of PHHI between 1 and 6 months of age. The clinical follow-up ranged from 2 years to 23 years (mean, 14 years). Mutations of the SUR1 and Kir 6.2 genes were examined in whole exons by the PCR-SSPC method using DNA extracted from white blood cells. RESULTS: SUR1 mutations were found in 5 of the 6 cases (83.3%), whereas no Kir 6.2 mutations were detected. Four of the 5 cases were found to have hetero-type mutations. These 4 cases and the 1 case without mutation were a pathologically focal type (head, 1; body, 2; tail, 2) and showed euglycemia after the operation. The other case was found to have a homo-type mutation and was pathologically diffuse. This case showed hypoglycemia and required medical treatment for several years. Diabetes developed 10 years after surgery. CONCLUSIONS: In the patients with either a hetero-type mutation or no mutation of the SUR1 gene, a focal type is suspected, whereas a homo-type mutation is considered to be associated with a diffuse type and also is a predictor of poor blood sugar control and a tendency toward diabetes. A genetic analysis of the SUR1 gene using peripheral white blood cells is considered a useful parameter to determine the optimal surgical strategy for the treatment of PHHI.
Subject(s)
ATP-Binding Cassette Transporters , Hyperinsulinism/genetics , Hypoglycemia/genetics , Mutation , Pancreatic Diseases/genetics , Potassium Channels, Inwardly Rectifying , Potassium Channels/genetics , Receptors, Drug/genetics , Blood Glucose/analysis , Diabetes Mellitus/epidemiology , Diabetes Mellitus/genetics , Female , Humans , Hyperinsulinism/pathology , Hyperinsulinism/surgery , Hypoglycemia/pathology , Hypoglycemia/surgery , Infant , Infant, Newborn , Longitudinal Studies , Male , Pancreas/pathology , Pancreas/surgery , Pancreatectomy , Pancreatic Diseases/pathology , Pancreatic Diseases/surgery , Sulfonylurea Receptors , Treatment OutcomeABSTRACT
To elucidate its effect on proinsulin processing, we introduced the expression of a Pittsburgh type-mutant, alpha1-protease inhibitor M/R (alpha1-PIM/R) and its chimera protein with growth hormone (GH) (GHalpha1-PIM/R) into MIN6 cells. In metabolic labeling and chasing experiments with [3H]-Leu and [35S]-Met, proinsulin appeared in the medium during stimulatory secretion only from MIN6 clones expressing GHalpha1-PIM/R and, surprisingly, alpha1-PIM/R, but not from the clones of either the control or alpha1-PI. The major part of alpha1-PIM/R was secreted through the constitutive pathway and about 10% of total secreted alpha1-PIM/R in the chase periods entered the regulated pathway. On the other hand, GHalpha1-PIM/R was mainly transported to the secretory granules and about 80% of the total secreted GHalpha1-PIM/R in the chase periods was secreted during stimulatory secretion. In the first 3 h chase periods without stimulation, only alpha1-PIM/R and no GHalpha1-PIM/R appeared in the medium, thus suggesting that alpha1-PIM/R might be transported through a constitutive-like pathway for those periods. The alpha1-PI, which had no inhibitory effect on proinsulin processing, showed similar secretion pathways to those of alpha1-PIM/R. This implies that some part of alpha1-PIM/R and alpha1-PI entered the regulated pathway, not due to any specific interaction between the processing endoproteases and serine protease inhibitors, but due to some type of passive transport in a nonselective manner. The inhibitory effect of alpha1-PIM/R in the regulated secretory pathway was slightly but clearly evident when it was expressed in MIN6 beta-cells.