Red cell sodium and ionic fluxes in patients with hyper- and hypothyroidism

To investigate the status of the Na+ concentrations [Na+]i, K+ concentrations [K+]i and ionic fluxes in red cells of human subjects with abnormal thyroid function, we measured the Na(+)-K+ pump activity as well as Na(+)-K+ cotransport (CoT), Na(+)-Li+ countertransport (CTT) and Na+ passive permeability in erythrocytes of 37 normal subjects, 19 untreated hyperthyroid patients, 12 treated hyperthyroid patients and 9 hypothyroid patients with T4 replacement. The mean [Na+]i value in the untreated hyperthyroidism group was significantly higher than that in the normal subjects (p less than .05), but not significantly different from that in the treated hyperthyroidism group. The mean [Na+]i value in the hypothyroidism with T4 replacement group, however, was significantly lower than that in the normal group (p less than .01). We did not find any significant difference of [K+]i in comparing each group. It was found that the Na(+)-K+ pump activity in erythrocytes was significantly increased in untreated hyperthyroidism (mean; 23.4% above control, p less than 10(-5], but there was no significant difference in treated hyperthyroidism and hypothyroid patients with T4 replacement. The rate constant for ouabain-sensitive Na+ efflux in the hypothyroidism with T4 replacement group was markedly higher than that in normal subjects (p less than .01), but not significantly different in the untreated hyperthyroidism group. We observed a significant increase of the Na+ CoT value in the patients with untreated hyperthyroidism as compared with that of the normal subjects (p less than .05), but there was no significant difference in the patients treated for hyperthyroidism and the hypothyroidism with T4 replacement group. However, the rate constant for Na(+)-CoT in the patients with hypothyroidism with T4 replacement was significantly higher than that in normal subjects (p less than .05). We observed a marked decrease of Na(+)-Li+CTT value in the patients with untreated hyperthyroidism versus that in the normal group (p less than .01). Passive Na+ permeability in the patients with untreated hyperthyroidism was markedly increased (p less than .05), and was markedly decreased in the patients with hypothyroidism with T4 replacement compared to normal subjects (p less than .01). It can be concluded from these studies that an increase in Na(+)-K+ pump activity in the patients untreated for hyperthyroidism might then be regarded as a secondary adaptive cellular response to higher [Na+]i values due to enhanced passive Na+ permeability, rather than a direct effect of the thyroid hormone.

Nephrotic syndrome associated with renal vein thrombosis--a report of 3 cases

The coexistence of nephrotic syndrome and renal vein thrombosis has been of medical interest since Rayer’s description in 1840. Renal vein thrombosis has been underdiagnosed because of its variable clinical and radiological findings but it becomes a more frequently recognizable clinical entity since diagnosis can be easily established by modern angiographic techniques. Generally it has been believed that renal vein thrombosis may cause nephrotic syndrome. But recent articles strongly suggest that renal vein thrombosis is a complication of the nephrotic syndrome rather than a cause. We report three cases of nephrotic syndrome associated with renal vein thrombosis.

Hyperkalemia by beta-fluoroethylacetate: a report of 2 cases

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2,3-diphosphoglyceric acid changes in uremia and during hemodialysis

The present study is an investigation of the mechanism of changes in erythrocyte 2,3-diphosphoglyceric acid (2,3-DPG) in patients with chronic renal failure during hemodialysis. The study was conducted on 7 Korean and 6 American patients on maintenance hemodialysis. The plasma pH of Korean patients was 7.31±0.02 before hemodialysis and 7.40±0.04 after hemodialysis (p<0.001). The pH of erythrocyte also increased from 7.13±0.02 to 7.20±0.03. The concentration of hemoglobin 2,3-DPG in Korean patients was 10.86±2.89 μmol/g before hemodialysis and 19.93±2.89 μmol/g after hemodialysis (p<0.001). Similar results were obtained in American patients. Hemoglobin 2,3-DPG was 12.54±2.53 and 18.76±6.73 μmol/g before and after dialysis respectively. Despite the presence of substantial anemia, hemoglobin 2,3-DPG prior to hemodialysis was significantly lower than the values obtained in the normal controls (17.45±4.3 μmol/g). The blood glucose increased from 93.3±8.5 mg/dl before dialysis to 117.1±6.1 mg/dl after hemodialysis in Korean patients but no significant change was detected in American patients. The increased blood glucose with hemodialysis observed in Korean patients was probably attributable to the lower baseline glucose concentration and the gain of glucose from dialysate, which had a glucose concentration of 186±34.1 mg/dl. The results suggest that the increase in 2,3-DPG with hemodialysis is probably caused by an increase of pH and an increased glucose utilization.