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Conjunctival capillary fragility (CCF) and skin capillary fragility (SCF) were studied by a negative-pressure suction cup method in 25 normal subjects and 38 diabetic patients with diabetic retinopathy. The CCF was significantly higher (P less than .001) in patients with diabetic retinopathy than in normal subjects; there was no significant difference in the SCF.
Capillary fragility has been examined in 110 elderly patients, excluding those patients who might have been expected to have abnormal fragility. Nonetheless, fragility appeared to be greater in elderly patients than in younger subjects. It was much increased in the non-paralysed arm of hemiplegic patients but not in the paralysed arm--perhaps because petechiae were obscured by trophic changes. Capillary fragility was significantly correlated with systolic blood pressure but not with age. This suggests that higher values in elderly patients may be related to the high prevalence of arteriosclerosis rather than to age itself.
Within-subject variation of capillary fragility with a 20 mmHg change in blood pressure has been studied in a series of elderly patients. Capillary fragility is increased by an average of 48% by a 20 mmHg rise in blood pressure. The reported association of capillarly fragility and blood pressure is thus artefactual rather than an indication of a higher prevalence of vascular abnormality in subjects with higher blood pressure.
Capillary fragility in man during exposure to 1-5 ATA air and after decompression from these pressures was studied by means of a petechiometer. A significant increase in capillary fragility was observed at 4 and 5 ATA air and after decompression from 3, 4, and 5 ATA air to normal pressure. It is suggested that this phenomenon may be associated with impairment of neurophysiological functions detectable only by special tests.
Calcium dobesylate was administered for 30 days to diabetics with or without clinical signs referable to microangiopathy and increased capillary fragility unaccompanied by coagulation and haemostasis disturbances. Good results were observed in 90% of cases. It is felt that the drug can also be used in the tertiary prevention of systemic microangiopathy, as well as the medical management of diabetic retinopathy.
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On the basis of previous biochemical observations, which have demonstrated the formation of complexes between anthocyanosides and some phospholipids, the AA. investigate the modifications induced by local and general administration of anthocyanosides 1) on the foreign body granuloma and 2) on the composition of the protein fractions in the exudate from the capillaries of the granulation tissue, growing on post-thromboflebitic or varicose leg ulcerations. The biochemical and histochemical data may show that the anthocyanosides protect the altered capillary walls with a double mechanism: a) increasing the endothelium barrier-effect through a stabilisation of the membrane phospholipids and b) increasing the biosynthetic processes of the acid mucopolysaccharides of the connective ground substance, by restoring the altered mucopolysaccharidic pericapillary sheat. This last effect may explain the marked increase of new-formed capillaries and collagen fibrils induced by the anthocyanosides.
The characteristic histologic change seen at 2 h in the Rumpel-Leede (Hess) test is, in addition to focal hemorrhage in the upper dermis, a perivascular lymphocyte infiltrate with focal areas of lymphocytic epidermal invasion. The histologic findings, even with the liquefaction degeneration, are similar to those of purpura simplex and indicate that, early in many forms of vasopermeability, the lymphocyte may be a primary inflammatory cell.
Medical practitioners often have difficulty in assessing the presence or severity of diabetic retinopathy. The tourniquet test is a method of assessing diabetic capillary fragility that has been felt to reliably correlate with background and proliferative diabetic retinopathy. We studied 100 consecutive diabetic patients and 50 age-matched controls in a masked fashion, using fundus photographs and fluorescein angiography to correlate the amount of capillary fragility with the presence and severity of background and proliferative diabetic retinopathy. Although the severity of diabetic capillary fragility did correlate with the presence and severity of diabetic retinopathy (p less than 0.001), this test was not as good an indicator of diabetic retinopathy as were other risk factors such as duration of diabetes (p much less than 0.001). The tourniquet test is unreliable in predicting the presence or severity of diabetic retinopathy because of its high false negative response rate.
The incidental discovery of scurvy in a patient with a symptomatic hiatal hernia has led to the identification of 9 other individuals with chemically proved vitamin C deficiency secondary to an expressed aversion to "acid" food in any form. These patients were screened with capillary fragility tests and serum ascorbic acid determinations from approximately 200 hiatal hernia and reflux patients. With resumption of a normal vitamin C intake, scattered deficiency symptoms disappeared and both capillary fragility tests and serum ascorbic acid levels returned toward normal. There were no wound healing problems.
Features of metabolism and haemostasis which are different in diabetics of both types in comparison with normal subjects were covered by the statistical method of multivariance analysis depending on the severity of diabetic retinopathy. In 29 diabetics without retinopathy, 46 patients with stage I or II, and 36 patients with stage III the following parameters could be found as optimal criteria for characterizing the extent of vascular changes: blood sugar concentration, concentration of sialic acid and HDL cholesterol in the serum, serum protein, sialic acid per protein volume, total cholesterol in the serum and capillary fragility and number of large spreading forms of platelets features of hemostasis. Thus, diabetic retinopathy is characterized by a wide spectrum of different features containing the parameters of hemostasis. Thrombocytic vascular interactions are characterized by platelet spreading and capillary fragility which are significant for the development of diabetic retinopathy.
Presomen, a preparation of natural conjugated estrogen has been applied to 81 ophthalmologic patients. Some patients received it as a preoperative measure for the prevention of hemorrhages, others were treated with the drug in order to facilitate the absorption of vitreous and retinal hemorrhages. The effect of the preparation on capillary fragility has likewise been studied. The literature contains contradictory reports on the mode of action of conjugated estrogens. Clinical observations show conjugated estrogens suitable for the prevention of hemorrhages in connection with surgical interventions.
Experimental thrombocytopenia results in endothelial alterations associated with bleeding. In this study prednisone was shown to prevent or reverse these changes, which supports the clinical inference that adrenocorticosteroids decrease capillary fragility in thrombocytopenia. Rabbits (3-4 kg), intraperitoneally injected with busulfan, developed 98-99% reductions in platelet count and hemorrhaged profusely. Orally administered prednisone (0.2 mg/kg or 1.0 mg/kg daily) reduced bleeding despite persistent thrombocytopenia. Tongue biopsies obtained after 3 days of prednisone treatment were examined by electron microscopy. Normal rabbits served as controls. 25 consecutive capillaries or venules from each of four animals in the control group and each of five experimental groups were examined for fenestrations, "thin spots" (<800 A thick), and mean wall thickness as determined by planimetry. Vessels from control animals had no thin spots or fenestrations, and the mean vessel wall thickness was 4,254+/-105 A SEM. The 100 vessels from the thrombocytopenic animals had a mean vessel wall thickness of 2,081+/-218 A (P < 0.001), and 42 had thin spots of fenestrations. After administration of the smaller dosage of prednisone, the mean vessel wall thickness increased to 3,556+/-40 A (P < 0.001), and only nine vessels had thin spots or fenestrations. With the larger dosage, only six vessels had thin spots or fenestrations and the mean vessel wall thickness of this group increased to 3,704+/-206 A (P < 0.005). All preparations demonstrated normal endothelial junctions. The data are consistent with the hypothesis that the bleeding of thrombocytopenia is caused by altered capillary and venule endothelium and that diminished bleeding observed with prednisone administration results from amelioration of these endothelial changes.
A retrospective study of 2,292 tonsillectomies revealed 12 cases of hereditary capillary fragility. These cases showed an increased morbidity from bleeding complications and accounted for 4.8 per cent of those with a secondary hemorrhage. When diagnosed, skin bleeding time should be carried out at the time of premedication, and, if prolonged, the procedure postponed.
Various thrombocyte functions and metabolic criteria were investigated in 309 test persons, among them 198 Patients affected with diabetes mellitus, 67 of type I and 131 of type II as well as 111 healthy control persons. From the variety of these factors an optimal amount was determined by means of the statistical method of multivariance analysis separating both types of diabetes and healthy control persons. In addition to haemoglobin A1 concentration, thrombocyte parameters have been found together with the degree of capillary fragility, adrenalin-induced aggregation, platelet aggregation test and clot retraction, which allow individuals to be assigned diagnostically to various groups of test persons. Thus, thrombocyte functions found in both types of diabetes and normal persons exhibit differences which may contribute to a diagnostic classification.
An epidemiological study of cerebrovascular disease in Akabane and Asahi, Japan, was made. (These cities are located near Nagoy, Japan.) The study population included 4,737 men and women aged 40 to 79 at the time of entry into the study. There were 4,186 persons who were examined and, of these, 264 cases of cerebrovascular attacks were observed between 1964 and 1970. The incidence rate of stroke in those persons not responding to the survey was 15.9 times higher than in those persons examined according to person-year observation in Akabane. The risk factors for cerebral hemorrhage and thrombosis were evaluated by age-adjusted and sex-adjusted relative risks. The predisposing factors to cerebral hemorrhage appeared to be high blood pressure, high left R wave, ST depression, T abnormality, capillary fragility counts, previous medical history of stroke and albuminuria. For cerebral thrombosis, the predisposing factors appeared to be high blood pressure, ST depression and funduscopic sclerotic findings, and those factors assumed to be significant were glycosuria and smoking habits. Ocular funduscopic abnormality was the most prominent risk factor for cerebral thrombosis, while high blood pressure and ECG abnormalities were highly related to cerebral hemorrhage. It was suggested that those subjects with a relatively higher blood pressure may have a higher relative risk of cerebral hemorrhage than those with a lower (normal range) blood pressure. A previous or family history of stroke also appeared significantly related to cerebral hemorrhage.
We used the multiple-indicator dilution technique to examine the kinetics of tracer oxygen distribution and uptake in the rat liver perfused in a nonrecirculating fashion with blood. 51Cr-labeled 18O2-saturated erythrocytes, labeled albumin, sucrose and water (the tracers for oxygen and vascular, interstitial and cellular references) were injected simultaneously into the portal vein. Timed anaerobic samples were collected from the hepatic vein and analyzed by mass spectrometry for relative 18O2 enrichment and radioactivity. In a set of experiments performed at 32 degrees C, oxygen uptake was substantially diminished; tracer oxygen profiles approached those expected for a completely recovered, flow-limited substance. At 37 degrees C, much larger tracer oxygen sequestration occurred. Experiments were carried out at each temperature at higher and lower hematocrit, and oxygen consumption at each temperature was found to be independent of hematocrit. The tissue space of distribution for tracer oxygen relative to the total sinusoidal vascular content was influenced by the hematocrit: it was smaller at higher hematocrit and larger at lower hematocrit, as expected. The derived partition coefficient of oxygen for liver cells relative to plasma (expressed in terms of the liver and plasma water spaces) was, on average, 2.62 ml/ml; it was independent of the hematocrit. Analysis of the indicator dilution experiments indicates that the tracer oxygen is distributed into tissue in a flow-limited rather than a barrier-limited fashion, and that with this, an ongoing concomitant intracellular sequestration of tracer can be seen.