Origin of the microangiopathic changes in diabetes

Successful plasma exchange in a 34-year-old woman with diabetic ketoacidosis and a thrombotic microangiopathy

Thrombotic microangiopathy (TMA) associated with diabetic ketoacidosis (DKA) is a rare complication reported in the pediatric setting. We report a case of an adult patient with new-onset DM, DKA, and TMA who was treated successfully with therapeutic plasma exchange (TPE). The patient underwent five procedures and experienced quick recovery in her platelet count and a near-normalization of her LDH. Within 3 days, ADAMTS13 activity was reported at 40.7% (>66.8%). After a protracted hospital course, mostly focused on treating the patient's bilateral hemorrhagic chemosis, the patient was discharged on hospital day 30. TMA is associated with a spectrum of diseases such as TTP and sepsis but, to our knowledge, it has not been reported in the setting of DKA in an adult patient. Evidence supports that metabolic alterations associated with DKA and its treatment disrupt basal hemostatic mechanisms and promote a thrombotic state. Although ADAMTS13 activity was only moderately decreased, our patient responded rapidly to TPE, with a striking increase and stabilization of her PLT count that was durable beyond discharge. As reported recently, patients who have TMA with ADAMTS13 activity levels >10% have a range of diagnoses, presentations, and outcomes. Although the underlying microangiopathic process is incompletely understood, these patients may respond well to TPE, as was seen in this case.

Prevalence of Microalbuminuria among Rural North Indian Population with Diabetes Mellitus and its Correlation with Glycosylated Haemoglobin and Smoking

INTRODUCTION

Macrovascular and microvascular complications of diabetes mellitus are a consequence of metabolic derangement mainly hyperglycemia. Diabetic nephropathy being one of them causes end stage renal disease. Hence, to detect renal involvement, microalbuminuria can be considered as an early marker.

AIM

To study mean albumin creatinine ratio (ACR) in type 1 and type 2 diabetes mellitus with respect to HbA1c, duration of diabetes and smoking.

MATERIALS AND METHODS

Two hundred cases of type 1 and type 2 diabetes mellitus and 100 controls, age and sex matched were included in this study and measured for spot urinary albumin, spot urinary creatinine, fasting plasma glucose and HbA1c.

RESULTS

It was observed that mean ACR was significantly elevated in type 1 and type 2 diabetes mellitus as compared to the controls. Mean ACR increases in diabetics with poor glycemic control, duration of diabetes and smoking.

CONCLUSION

The early detection of microalbumin in diabetics can significantly reduce the progression of renal complications and before the development of proteinuria.

Hyperbaric oxygen therapy ameliorates the blood-retinal barrier breakdown in diabetic retinopathy

BACKGROUND

To study the effect of hyperbaric oxygen (HBO) therapy on diabetic retinopathy in a streptozotocin-induced diabetic rat model.

METHODS

Sprague-Dawley albino male rats were divided into three groups. The three groups were as follow: (i) non-diabetic control group (non-DM control); (ii) diabetic control group (DM control); and (iii) diabetic rats receiving hyperbaric oxygen therapy (DM HBO). Rats in DM HBO group were incubated in an oxygen monoplace chamber. The HBO condition was set at 2.5 atmospheres and 100% oxygen. The duration of a single HBO treatment was 90 min. Rats in DM HBO groups received HBO three times per week for 3 months. Retinal vascular permeability was assessed by measuring fluorescein isothiocyanate-labelled bovine albumin and retinal Evans blue leakage into the retina.

RESULTS

We found that the retinal parenchyma showed prominent thickening but not statistically significant in rats with DM, corresponding to the retinal oedema, compared with the control and DM HBO groups. fluorescein isothiocyanate relative fluorescence intensity (Mean+/-SE) in normal control animals, diabetic animals, and HBO-treated diabetic animals was 356+/-47, 865+/-78, and 518+/-49, respectively, demonstrating significant difference between the means of diabetic and HBO-treated diabetic animals, and between means of control and diabetic animals (n=8, P<0.05). Retinal Evans blue leakage in control animals, diabetic animals, and HBO-treated diabetic animals was 7.6+/-2.9, 18.5+/-4.2 and 10.2+/-3.1 microL plasma/g retinal dry weight/h, respectively, demonstrating significant difference between the means of diabetic and HBO-treated diabetic animals, and between means of control and diabetic animals (n=8, P<0.05).

CONCLUSION

HBO therapy may diminish the extent of the increased blood-retinal barrier breakdown in diabetic animals.

Structural impairments in optic nerve of diabetic rats ameliorated with the aldose reductase inhibitor

Structural impairments of optic nerve fibers in the streptozotocin-induced diabetic rat were investigated using morphometric analysis. The effect of aldose reductase inhibitor (ARI) on abnormalities in myelinated nerve fibers was also evaluated. Three months after the induction of diabetes, loss of body weight and significantly elevated levels of serum glucose were observed. Light microscopic examination revealed that the mean size of the optic nerve in the diabetic rat remained unchanged. Electron microscopic morphometry showed the significantly smaller cross-sectional size of axons and myelin but no change of myelinated fiber number. Reductions of myelinated fiber size was especially remarkable in the larger fibers. ARI treatment improved structural abnormalities without any changes in body weight and blood glucose level. Reduction of axon size and myelin/axon ratio was completely inhibited by ARI treatment. These findings suggest that structural impairment may contribute to the abnormalities of psychophysical and electrophysiological measurements detected in diabetes. Moreover, ARI treatment, which can improve the polyol metabolism, may have a beneficial effect on optic nerve impairment in diabetes.

Microangiopathic hemolytic anemia as a complication of diabetes mellitus

A mature-onset diabetic patient who developed microangiopathic hemolytic anemia (MHA) is presented. Although numerous causes of hemolysis are reported in the literature, MHA is a rare complication of diabetes. The proposed mechanism of hemolytic anemia is thought to be related to the abnormal formation of cell membranes in the diabetic environment. The ratio of cholesterol to phospholipid in the core of the membrane is altered in diabetics; as a result, the red blood cell wall becomes rigid and nondeformable. The abnormal cells becomes disrupted as they circulate through the microangiopathic blood vessels. The mechanism of action of the antiplatelet agents is to enhance cell membrane compliance. With improved cell-wall compliance, one can expect a reduction in hemolysis, as occurred in our patient. The literature on diabetes mellitus-related microangiopathic hemolytic anemia is reviewed.

Role of glucose regulatory mechanisms in diabetic retinopathy

Images