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Biomedical subjects

J E Lewy

Publications and source records attributed to J E Lewy.

At least 37 records · Page 2Linked to original sources
PubMed1985

Erythropoietin response to anaemia in children with sickle cell disease and Fanconi's hypoproliferative anaemia.

The erythropoietin response to anaemia was compared in 30 children with haemolytic anaemia and in 5 children with Fanconi's hypoproliferative anaemia. Serum erythropoietin was measured by radioimmunoassay. In children with haemolytic anaemia the serum erythropoietin concentration increased exponentially with decreasing haematocrit values (r = 0.74; p less than 0.001). Serum erythropoietin levels also correlated with reticulocyte counts (r = 0.62; p less than 0.001). Children with Fanconi's hypoproliferative anaemia had considerably higher serum erythropoietin levels than children with haemolysis for the same degree of anaemia. These data indicate that erythropoietin production in Fanconi's anaemia may be dependent on other factors in addition to the degree of anaemia and relative hypoxaemia.

Adolescent↗
PubMed1985

Erythropoietin and inhibitors of in vitro erythropoiesis in the development of anemia in children with renal disease.

The relative roles of erythropoietin and potential inhibitors of erythropoiesis in the development of anemia in children with renal disease have been studied. Thirty-five children with renal disease of varied origins and severity were compared with 30 children with anemia of similar severity and with normal renal function. Serum erythropoietin was measured by radioimmunoassay; erythroid (CFU-E) and granulocytic (CFU-GM) progenitor cell growth were assessed in fetal mouse liver cell and normal human bone marrow cell cultures, respectively. The degree of serum inhibition of in vitro CFU-E growth in children with renal disease correlated with both creatinine clearance (r = 0.59, P less than 0.001) and hematocrit level (r = 0.55, P less than 0.005). Serum from children with renal disease inhibited in vitro CFU-E growth in a dose-related manner. Normal serum did not inhibit CFU-E growth in culture. The mean serum erythropoietin concentration was significantly (P less than 0.025) higher in children with anemia of renal disease (32.4 +/- 2.4 mU/ml) in comparison with serum values in normal children (19.6 +/- 1.5 mU/ml), but serum erythropoietin levels did not correlate with hematocrit level, creatinine clearance, or serum inhibition of in vitro erythropoiesis. In contrast, children with anemia and normal renal function showed a significant (P less than 0.001) linear increase in serum erythropoietin concentration (range 28.7 to 327 mU/ml), increased reticulocyte count, and stimulation of CFU-E formation with decreasing hematocrit levels. Coincubation of human urinary erythropoietin in the presence of serum from patients with uremia revealed markedly less immunoreactivity in the radioimmunoassay and less biologic activity in the fetal mouse liver CFU-E assay for erythropoietin than when erythropoietin was incubated with normal human serum, suggesting some alteration of erythropoietin in the presence of uremic serum, which reduced both the immunologic and biologic activity of erythropoietin. Normal and uremic sera inhibited CFU-GM growth to the same degree in comparison with controls. In conclusion, relative erythropoietin deficiency, direct alteration in the biologic activity of erythropoietin by uremic toxins, and serum inhibition of erythroid progenitor cells in the bone marrow are probably important factors in the pathogenesis of anemia in children with renal disease.

Acute Kidney Injury↗
PubMed1981

Familial nephrotic syndrome and focal segmental glomerulosclerosis.

Three of five siblings developed a steroid-resistant nephrotic syndrome with focal segmental glomerulosclerosis within a four-month period. Two of the siblings with nephrotic syndrome (Patients 1 and 2) also have sickle cell anemia; the third (Patient 3) carries the thalassemia trait. The dizygotic twin brother of Patient 2 has sickle cell anemia, but does not have the nephrotic syndrome. The nephrotic syndrome of patient 1 was resistant to corticosteroid and cyclophosphamide therapy and she developed severe renal failure 14 months after onset. The nephrotic syndrome of Patients 2 and 3 was steroid resistant but was partially responsive to cyclophosphamide therapy. They have persistent proteinuria with mild elevation of serum creatinine concentration and hypertension 5 1/2 years after diagnosis. In this family, the nephrotic syndrome appeared unrelated to the specific hemoglobinopathy, HLA type or mixed lymphocyte culture responsiveness despite the similarity of the renal disease.

Adolescent↗
PubMed1981

Recurrent nephrotic syndrome with three successive renal allografts.

A girl with idiopathic steroid-resistant nephrotic syndrome was studied at onset of the disease at 6 years of age and during recurrences of the nephrotic syndrome after successive transplantations of three renal allografts. Focal glomerulosclerosis was demonstrated shortly after onset of the original disease with progression to renal insufficiency over 14 months. Recurrence of the nephrotic syndrome was documented 4 weeks following transplantation of the first renal allograft and a biopsy demonstrated focal segmental glomerulosclerosis without evidence of rejection. By 13 months, recurrent disease had caused renal failure requiring dialysis. After transplantation of the next long-functioning graft, the nephrotic syndrome rapidly recurred with urinary protein excretion of 8 g/day and normal glomerular filtration rate at 8 weeks. After the 5th month, progressive renal insufficiency developed and dialysis was resumed at 10 months after transplantation. The nephrectomy specimen showed advanced focal segmental glomerulosclerosis and chronic rejection. Early after the last renal allograft, she had mild persistent proteinuria and then developed nephrotic syndrome at 10 months which was attributed to chronic rejection. The graft was lost to delayed accelerated rejection at 17 months. The rapid recurrence of nephrotic syndrome after transplantation of each of the first two long-functioning allografts to this patient is most consistent with recurrence of original disease. However, observations in a subsequent graft demonstrated that rapid recurrence of the original disease is not inevitable.

Adolescent↗
PubMed1981

Renal function in rats with unilateral proteinuria produced by renal perfusion with aminonucleoside.

Left (L) renal perfusion with an aminonucleoside of puromycin (PA), was used to produce unilateral proteinuria in 15 rats to examine the mechanisms responsible for renal salt retention in the nephrotic syndrome. Thirteen control rats underwent L renal perfusion with isotonic saline. Animals were studied 8 (group I) or 13 (group II) days after perfusion. Renal perfusion with saline per se did not change the glomerular filtration rate, renal plasma flow, or absolute and fractional excretion of sodium (Na) from the perfused kidney. PA animals showed a significant decrease in glomerular filtration rate from the perfused kidney and a proportional decrease in the absolute excretion of Na from the PA perfused kidney as compared to the right kidney. The fractional excretion of Na was equivalent in the L and R kidneys of the PA animals. The mean absolute Na excretion from the nonproteinuric R kidney of PA rats was almost twice that of the R kidney of the controls. The increased Na excretion by the nonproteinuric kidney of the PA animals compensated for the sodium retention by the proteinuric kidney.

Animals↗
PubMed1980

Delayed puberty in males with chronic renal failure.

The effects of chronic renal failure on the pituitary-testicular axis of 31 males, aged 11.7 to 20.0 yr (mean, 16.0 yr) were studied. Nine patients not on hemodialysis (group I) had serum creatinines between 2.5 and 8.0 mg/dl, 10 patients were on hemodialysis (group II) and 12 patients had received a renal transplant (group III). The Tanner stage of pubertal development was delayed relative to chronologic age. Testosterone (T), delta 4-androstenedione (delta 4), and urinary 17-keto steroids were normal when related to pubertal stage in groups I and II; and dehydroepiandrosterone (DHEA) and DHEA sulfate (DS) were in the low normal range. In group III, adrenal androgens (delta 4, DHEA, DS) were decreased as a consequence of prednisone therapy whereas T was normal. Luteinizing hormone levels were normal in all. Follicle-stimulating hormone levels were normal in all. Follicle-stimulating hormone (FSH) was significantly increased in groups I and II. In group III, FSH was normal in 6 of 9 patients with serum creatinine concentrations < 2 mg/dl. FSH levels were uniformly elevated in Tanner I-V patients with creatinines > 2 mg/dl. The data shows that FSH is elevated in patients with chronic renal failure even in prepuberty and early adolescence. This may reflect damage to germinal epithelium prior to the advent of spermatogenesis, whereas Leydig cell function appears to remain intact.

Adolescent↗
PubMed1979

Safety of intravenous diazoxide in children with severe hypertension.

The safety and efficacy of diazoxide administered intravenously in the treatment of children with acute severe hypertension have been evaluated by a collaborative study. Observations of the response of blood pressure in 36 patients, ranging in age from two months to 18 years, during the initial episode of hospitalization reveal diazoxide treatment to be effective in lowering blood pressure in 94 per cent of the cases. No serious adverse circulatory, fluid and electrolyte, metabolic or hematologic effects were observed. Symptomatic and subjective reactions observed with diazoxide administered intravenously to children were identical with those described in adults. Reinstitution of other means of antihypertensive therapy is safe and effective when delayed until the transiently induced period of hypotension has passed. Repeated use of diazoxide for subsequent recurrence of severe hypertension was equally effective and safe in 93 per cent of the instances. The results lead us to recommend the use of intravenous diazoxide for treatment of children with severe symptomatic hypertension especially when it is refractory to control by other hypertensive agents.

Adolescent↗
PubMed1978

Somatomedin and growth retardation in children with chronic renal insufficiency.

The somatomedins are a family of growth hormone-dependent insulin-like peptides which have been postulated to mediate the actions of pituitary growth hormone on skeletal tissue. The somatomedin peptides are part of a larger family of growth factors. Somatomedin has been measured by bioassays, by radioreceptor assays, and recently by a radioimmunoassay. Bioassays are influenced by glucocorticoids, sulfate, heparin, and other inhibitors; radioreceptor assays from different laboratories presently give conflicting results but early experience with the immunoassay is promising. Somatomedin levels are low in hypopituitary states, in malnutrition, and in general when growth hormone is low. Somatomedin's levels in uremia are variously reported. Most bioassays report low values, although the hole of inhibitors is not clear. Values by radioreceptor assays are normal or elevated, but their specificity is unproven. No data are available using radioimmunoassay. No study has addressed end-organ responsivity in uremia.

Biological Assay↗
PubMed1978

Stimulation of p-aminohippurate extraction in the maturing rabbit kidney.

In vivo studies were performed to evaluate maturational changes in PAH extraction (EPAH) in the rabbit and to determine whether accelerated maturation of this process could be achieved. Fifty-four animals were injected with penicillin before study at 10, 14, 21, or 28 days of life. Forty-eight rabbits served as saline-injected controls. PAH extraction in controls increased from 29.3 +/- 2.4% at 10 days of age to 35.9 +/- 3.3% at 14 days, 59.7 +/- 3.5% at 21 days, 71.6 +/- 1.9% at 28 days, and 72.7 +/- 2.3% at 35 days of life. Penicillin injection on the 3 days before study resulted in enhancement of EPAH on days 10 and 14 to 42.7 +/- 2.4% and 65.0 +/- 3.2% (P less than 0.005). On days 21 and 28 less stimulation was noted (68.7 +/- 2.3%; 76.0 +/- 4.1%). Preinjection on days 6--9 with study delayed to day 14 also led to augmentation (46.7 +/- 3.7% P less than 0.05) but less than that achieved after injection on days 10--13. These data suggest that EPAH stimulation may be transient, descreases as maturation is approached and is likely related to substrate availability.

Aminohippuric Acids↗
PubMed1978

Failure to thrive associated with renal disease.

Failure to thrive is a clinical syndrome usually associated with severely reduced increments in height and weight. It is commonly present in patients with chronic renal failure and occurs occasionally in patients with recurrent urinary-tract infections or tubular disorders. Renal osteodystrophy, protein-calorie malnutrition, and chronic glucocorticoid administration have been shown to be important causes of growth failure in patients with renal disease. Altered hormone production, metabolism, or peripheral utilization and acidosis may be causally related to growth failure. Such factors as anemia and hypos-thenuria appear to play no direct role.

Acidosis↗
PubMed1978

The use of furosemide in the treatment of edema in infants and children.

One hundred thirty-seven courses of furosemide therapy were given to 106 hospitalized pediatric patients with salt and water retention associated with cardiac or renal disease. The diuretic was effective and safe in the pediatric age group when administered acutely as a parenteral medication and over a long-term course by the oral route in the doses and at the time intervals used in this study. On the basis of each kilogram of body weight, the infants with edema as a result of cardiac failure and the children with edema secondary to renal disease responded equally well to furosemide therapy.

Administration, Oral↗