תוצאת חיפוש

Islet Autoantibody Assays in Type I Diabetes can Replace ICA Test

Daniel Lazar, Naomi Weintrob, Natalia Abramov, Sara Assa, Konstantin Bloch, Regina Ofan, Hadassa Ben-Zaken, Pnina Vardi

Institute for Pediatric Endocrinology and Diabetes, Schneider Children's Medical Center, Petah Tikva and Felsenstein Medical Research Center, Tel Aviv University

Islet cell antibodies (ICA) continue to serve as the basis of the principal serological test for definition of active autoimmunity of beta-cells. Its disadvantages are the need for human pancreatic tissue and difficulty in obtaining quantitative results. In the past decade biochemically-defined beta-cell antigens were described, leading to the development of sensitive and specific autoantibody assays, to predict insulin-dependent diabetes mellitus (IDDM). We examined the value of combined biochemically-based serological assays, such as autoantibodies to insulin (IAA), glutamic acid decarboxylase (GADA) and ICA512 (ICA512A) to replace the traditional ICA assay.

Blood samples of 114 newly diagnosed IDDM patients, aged 12‏5 yrs (range 2 months - 29 years) were tested for ICA (indirect immunofluorescence), IAA, GADA and ICA512A (radiobinding assay). The latter 2 assays were performed using recombinant human [35S]-labeled antigen produced by in vitro transcription/translation. We found that fewer sera scored positive for ICA and/or IAA (80.7%, 92/114) than for 1 or more of IAA, GAD, or ICA512 (88.6%, 101/114). We conclude that combined testing for IAA, GAD and ICA512 can replace the traditional ICA/IAA test to predict IDDM and is helpful in the differential diagnosis of insulin-dependent and noninsulin-dependent diabetes.

Progression of Diabetic Retinopathy after Cataract Extraction

Y. Raniel, Y. Teichner, Z. Friedman

Annette and Aron Rozin Dept. of Ophthalmology, Bnai-Zion Medical Center and Bruce Rappaport Faculty of Medicine, The Technion, Haifa

A prospective study of the effect of cataract extraction with intraocular lens implantation on the course of diabetic retinopathy (DR) in 44 patients (59 eyes) was carried out. It showed that in the 1-3 years following surgery, there was progression of DR (including development of newly formed retinopathy) in 35% of the patients (28.8% of eyes). Progression was more marked in patients with pre-operative bilateral DR compared to those without bilateral DR (77% and 16% respectively). Insulin dependence did not play a role in progression. Final visual acuity was better in patients without pre-operative DR, as well as in eyes without progressive retinopathy.

Red Cell Na+/H+ Exchange and Role of Protein Kinase C in its Stimu-Lation in Diabetes Mellitus, Essential Hypertension and Nephropathy

Wladimir Koren, Robert Koldanov, Edna Peleg, Eva Izsak, Meir Berezin, Talma Rosenthal

Dept. of Medicine C, Hypertension Unit and Endocrinology Institute, Chaim Sheba Medical Center, Tel Hashomer

Na+/H+ exchange (NHE) was measured as maximal initial velocity of pH-dependent H+ efflux from red cells into an alkaline medium containing Na+ in patients with insulin-dependent or noninsulin-dependent diabetes, with and without hypertension and in normoglycemic, essential hypertensives and normal controls (50 subjects in each subgroup). Maximal velocities of NHE were found in microalbuminuric patients in all subgroups, and NHE correlated with the rate of microalbuminuria (r=0.61, p=0.02). Daily insulin requirements were greater in those with elevated NHE (84±8 vs 42±4 U/day). There was no correlation between NHE and levels of plasma glucose, HbA1 and plasma aldosterone and lipid profile and PRA. NHE was correlated with plasma prolactin (r=0.51, p=0.02) and PTH r=0.24, p=0.05). In uremic patients, NHE was inversively correlated with creatinine clearance (r=-0.48, p=0.03). Since calphostin C, a selective inhibitor of protein kinase C, lowered increased NHE in vitro, the protein kinase C-dependent pathway of the exchanger regulation was concluded to be responsible for NHE activation in diabetes mellitus and essential hypertension.

Temporal Hemianopia And Diabetes Insipidus Following Head Injury

M. Zaaroor, D. Goldsher, M. Feinsod

Center for Treatment and Applied Research in Head Injuries, Dept. of Neurosurgery and Diagnostic Radiology Dept., Rambam Medical Center and Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa

Bitemporal hemianopia and diabetes insipidus following head injury are caused by a lesion in the center of the optic chiasm, together with injury to the adjacent pituitary stalk or the hypothalamus. This combination was thought to be a rare complication of severe head injury. The case of a 16-year-old male is presented, which together with recent reports suggests that this relatively under-recognized syndrome is not infrequent, that it may follow even minor head injury, and that magnetic resonance imaging can demonstrate the chiasmal lesion.