Search PubMed⌕ Search

Biomedical subjects

B Gauthier

Publications and source records attributed to B Gauthier.

At least 55 records · Page 3Linked to original sources
PubMed1990

Hepatitis-B-associated glomerulonephritis: pathology, pathogenesis, and clinical course.

Hepatitis-B-associated glomerulonephritis (HBGN) is a distinct entity occurring frequently in hepatitis-B-prevalent areas of the world. The disease affects both adults and children who are chronic hepatitis-B-virus (HBV) carriers with or without a history of overt liver disease. The diagnosis is established by serologic evidence of HBV antigens/antibodies, presence of an immune complex glomerulonephritis, immunohistochemical localization of 1 or more HBV antigens, and pertinent clinical history, when available. In this study we present clinicopathologic and follow-up findings in 12 patients (7 children, 5 adults) with hepatitis-B-associated glomerulonephritis. Twelve patients provided 15 renal biopsies and 1 specimen of kidney tissue, obtained at autopsy; these were examined by light microscopy, electron microscopy, and immunohistochemical methods. Membranous glomerulonephritis (MGN) with or without mesangial proliferation was noted in 7 biopsies, mesangiocapillary (membranoproliferative) glomerulonephritis (MCGN) in 5 biopsies, and proliferative glomerulonephritis with or without membranous changes in 2 biopsies. Tubulointerstitial changes were minimal except in 3 adults, in whom they were attributable to arterionephrosclerosis. Ultrastructural findings included the presence of considerable amounts of focal or diffuse granular electron-dense deposits in the glomeruli, in the subepithelial, subendothelial, and mesangial locations, occasionally destroying or replacing the lamina densa of the basement membrane. Variable mesangial proliferation was also observed, with interposition, with focal irregular reduplication of the basement membranes and rare clusters of spherical particles, probably representing viral particles in the deposits. In addition, granular deposits along tubular basement membranes were seen in 1 case. The glomerular deposits stained for 2 or more immunoglobulins, the predominant one being IgG, and variably also for complement components (C3, C4 and C1q). Hepatitis B viral antigens (HBsAg, HBcAg, HBeAg) were demonstrated using acid elution techniques in the deposits in all biopsies where frozen tissue was available, singly or in a variety of combinations and intensities. There were deposits of IgG, C3, C1q, and HBsAg along the tubular basement membranes in 1 case. Follow-up biopsies in 2 cases, 2 and 5 years apart, showed a transformation from a diffuse MGN to MCGN with segmental membranous features. Follow-up biopsy after 3 years in the third patient, who went into clinical remission, revealed partially resolving glomerular lesions. Renal lesions secondary to chronic liver disease, parasitic diseases, certain tropical nephropathies, and lupus nephritis are some of the diseases that may morphologically resemble HBGN. Recognition and differentiation of HBGN from other entities may have significant prognostic and therapeutic implications.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1989

Estimation of glomerular filtration rate in anorectic adolescents.

Severe malnutrition has been associated with a decrease in fat and lean body mass, as well as in renal function. This study was designed to evaluate the estimation of glomerular filtration rate (GFR, ml/min per 1.73 m2) in malnourished teenagers, by using the formula GFR = kL/Pcr (where L is body height, Pcr is plasma creatinine concentration and k is a proportionality constant relating muscle mass to body size that has been found to equal 0.7 in adolescent boys and 0.55 in girls). Body composition was estimated using anthropometric measurements and urinary creatinine excretion (UcrV). Malnourished female patients showed depletion of fat and muscle, whereas males had primarily decreased muscle mass. There was a good correlation (r = 0.74) between anthropometric [arm muscle volume (AMV)] and chemical UcrV estimates of muscle mass. However, our previously validated estimate of GFR did not give reliable results in this group of malnourished teenagers, probably because their muscle mass was so greatly altered by the severity of malnutrition. Therefore, we used anthropometric measurements and Pcr, to estimate GFR by multiple linear regression. The best prediction was obtained by using AMV/Pcr and the observed/expected (for age, height and sex) weight ratio (WR): GFR (ml/min) = 0.06 AMV/Pcr + 131 WR - 79, r = 0.82, n = 13. We confirm that malnutrition in adolescents is associated with decreased GFR and conclude that the resulting variability in body composition limits the possibility of estimating GFR from Pcr and height.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

A comparison of three nocturnal enuresis treatment methods.

To evaluate the efficacy of an operant approach that includes the bell and pad for the treatment of enuresis (Tangible Rewards with Fading), it was compared with an established operant method that includes the bell and pad (the Dry Bed method) and to a conventional Bell and Pad method. Although there were no overall statistically significant differences among the three methods, individual pairwise comparisons were of interest; the Dry Bed method had no advantage, but the Tangible Rewards with Fading method tended to have more patients reach a 14-day dryness criterion (p less than 0.10) and tended to have fewer patients relapse after treatment (p less than 0.08) than the Bell and Pad method.

Behavior Therapy↗
PubMed1989

Familial thin basement membrane nephropathy in children with asymptomatic microhematuria.

A review of 130 children with persistent microhematuria showed that the most common abnormality was a form of hereditary nephritis for wich we propose the term 'familial thin basement membrane nephropathy' (FTBMN). This lesion is not as severe as that of Alport's syndrome but carries a guarded prognosis. Family histories, urinalyses and audiograms systematically done on parents and other relatives show that FTBMN may be present in as many as 39% of children with persistent microhematuria and that careful family studies identify children likely to have this lesion.

Adolescent↗
PubMed1988

Platelet vasopressin levels in childhood idiopathic nephrotic syndrome.

Despite the importance of disturbances in plasma volume in nephrotic patients, the only clinically accepted measurement of this value in common use is plasma renin activity. We assessed the usefulness of plasma vasopressin levels as an index of plasma volume in patients with idiopathic nephrotic syndrome. However, since 80% to 90% of arginine vasopressin circulates bound to platelets, we measured vasopressin levels in platelet-rich and platelet-poor plasma. The nephrotic patients (n = 19) had significantly higher vasopressin levels in platelet-poor and platelet-rich plasma compared with controls (3.2 +/- 0.6 vs 1.0 +/- 0.3 pg/mL, and 10.4 +/- 3.6 vs 3.3 +/- 0.6 pg/mL. respectively). The percent binding of vasopressin to platelets was reduced in nephrotic patients compared with controls (50.2% +/- 6% vs 70.4% +/- 2.9%). The values for platelet-poor vasopressin, but not platelet-rich vasopressin, correlated significantly with the plasma renin activity (r = .83). We conclude that in nephrotic patients, platelet-poor vasopressin levels correlate with plasma renin activity and may provide a useful measure of minute-to-minute vasopressin release in response to changes in plasma volume.

Adolescent↗
PubMed1987

Parenteral calcitriol for treatment of severe renal osteodystrophy in children with chronic renal insufficiency.

Renal osteodystrophy is a common and incapacitating complication of chronic renal failure in children. Standard therapy with oral calcium supplements, phosphate binders, and vitamin D preparations is often inadequate to control progressive bone disease. We report the use of parenteral calcitriol therapy in two children, aged 2 and 15 years, respectively, with chronic renal failure. This treatment effectively suppressed secondary hyperparathyroidism in both patients, causing a nearly 50% reduction in circulating parathyroid hormone level and a parallel decline in serum alkaline phosphatase activity. In the younger patient, therapy was associated with healing of subperiosteal bone resorption and accelerated growth velocity. These findings indicate that parenteral administration of calcitriol may be an effective treatment option in some patients with refractory renal osteodystrophy and secondary hyperparathyroidism.

Administration, Oral↗
PubMed1985

Intrarenal hemangiomas in the Klippel-Trenaunay syndrome.

The Klippel-Trenaunay syndrome is composed of the triad of unilateral limb hypertrophy, abnormalities of the deep venous system, and port-wine hemangiomas. An interesting case is presented in which there were multiple abnormalities of the renal veins and intrarenal hemangiomas resulting in renal failure in addition to the usual peripheral abnormalities.

Angiomatosis↗
PubMed1985

A simple estimate of glomerular filtration rate in adolescent boys.

We reexamined the relationship between creatinine clearance (Ccr) and body habitus in 212 girls and 356 boys, including 181 boys and 69 girls between 13 and 21 years of age. The use of formula Ccr = k L/Pcr, where k = 0.55 for the calculation of GFR, resulted in a significant underestimation of GFR in adolescent boys but was suitable for girls. In 51 adolescent boys the equation Ccr = 0.7 L/Pcr resulted in an accurate estimate of GFR. Regression analysis in 133 boys aged 3 to 21 years showed that the constant k increased gradually and linearly with age (r = 0.35, P less than 0.01). GFR could be better estimated for boys of any age by the linear bivariate equation Ccr = 1.5 (age) + 0.5 (L/Pcr), where age is given in years (r = 0.82, P less than 0.001). This equation yielded slightly better results than did 0.7 L/Pcr in 91 additional clearance studies performed in adolescent boys with native kidneys or functioning renal transplants. The larger value for the constant k (0.7) and the age correction for GFR reflect the greater rate of urinary creatine excretion (and thus muscle mass) per unit of body mass in adolescent boys.

Adolescent↗
PubMed1984

[Not Available].

Explore the source record for details and available documents.

France↗
PubMed1978

Characteristics of the inhibition of serum alkaline phosphatase by theophylline.

1. The effect of various parameters on the inhibition of alkaline phosphatase activity by theophylline was studied. The influence of pH is great, being optimum for a value of 9.4. The temperature and the magnesium ion concentration have no to low effect. 2. The nature of the substrate and the nature of the buffer in which the enzymatic activity is measured have an effect:by measuring the activity of alkaline phosphatase in serum by a method with phenolphthaleinphosphate in Tris buffer, a negligible interference by therapeutic or toxic levels of theophylline is observed. 3. The inhibition by theophylline varies greatly with the origin of alkaline phosphatase: the liver isoenzyme is strongly inhibited, the intestinal one to a lesser degree and the placental isoenzyme almost not inhibited. 4. The inhibition of the liver and intestinal isoenzymes are uncompetitive and the inhibition constants were measured.

Alkaline Phosphatase↗