摘要:

Ammonium is the most important component of renal acid excretion. A reduced rate of ammonium excretion is the common feature of the group of diseases called distal renal tubular acidosis. We have presented an alternative approach to patients with distal acidification defects based upon the pathophysiology of these disorders. Accordingly, the purpose of this review is to describe a revised classification based on our current understanding of collecting duct hydrogen ion secretion and ammonium addition to the lumen of the distal nephron. We have subdivided these defects into four groups: disorders of the collecting duct proton pump (pump defects); failure to generate and/or maintain an appropriate electrical gradient to favor hydrogen ion secretion (voltage defects); back-leak of hydrogen ions across an abnormally permeable collecting duct membrane (gradient defects), and diminished availability of NH3 in this nephron segment (NH3 defects). These four subtypes can be identified by measuring the urine pH and PCO2 under appropriate circumstances and evaluating the renal excretion of ammonium and potassium.

ISSN:0250-8095    

DOI:10.1159/000166895

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

The effects of treatment with hydrochlorothiazide combined with amiloride were compared to hydrochlorothiazide treatment alone in 2 brothers with congenital nephrogenic diabetes insipidus. Whereas both modalities of treatment resulted in reduction in voiding frequency and urine volume, decrease in daily fluid intake and increase in urine osmolality, the two-drug combination was found to be superior to hydrochlorothiazide alone by preventing urinary potassium losses, hypokalemia, and alkalosis. It was also found that amiloride had a certain additive effect to the thiazide in terms of increasing initial urinary sodium excretion, reducing urine volume and free water clearance, and lowering serum sodium concentration and osmolality. Similar comparison of the hydrochlorothiazide-amiloride regimen to treatment with the hydrochlorothiazide-tolmetin combination in 1 of the patients revealed that the effectiveness of both diuretic modalities was close with slight advantage of the former. Treatment of the 2 patients for 10 months with hydrochlorothiazide and amiloride showed no adverse effects and consistent reduction in fluid intake and urine volume. It is concluded that the hydrochlorothiazide-amiloride regimen is superior to hydrochlorothiazide alone and can be a satisfactory alternative to the hydrochlorothiazide-prostaglandin synthetase inhibitor combination in the treatment of congenital nephrogenic diabetes insipidus.

ISSN:0250-8095    

DOI:10.1159/000166896

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

Patients with IgA nephropathy have elevated serum levels of polymeric IgA, probably due to an increase in their synthesis by peripheral blood mononuclear cells, and specific abnormalities in the immunoregulation of IgA. The existence of familial cases of IgA nephropathy, as well as the published association of this nephropathy with some antigens of the HLA system, decided us to test the hypothesis that some of these alterations might be genetically controlled. For this reason we studied some of these immunological assays in 25 first-degree relatives of 7 patients with IgA nephropathy and 22 control subjects matched for age and sex. An abnormal immunological assay was found in at least 1 relative of all families examined. Thus, 16 of 25 relatives had a significant increase in the percentage of polymeric IgA-producing cells after 7 days of culture in the presence of pokeweed mitogen. Some derangement in the concanavalin A generation of specific IgA suppressor cells was found in 11 out of 25 relatives. These results are, though in lower frequency, similar to those seen in patients and suggest that the IgA-immunological abnormalities observed are genetic markers, even if they cannot by themselves explain the pathogenesis of the IgA nephropathy. The absence of IgA immune complexes seen in relatives as well as their high prevalence in patients suggest that in predisposed subjects other factors (genetic or not) are required for the development of IgA nephropathy.

ISSN:0250-8095    

DOI:10.1159/000166897

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

Clinical and immunological data are reported of 12 patients suffering from Wegener’s granulomatosis and severe renal involvement. Although 9 patients recovered from their acute illness, at long-term follow-up a relapse occurred in 4 of these 9 patients. Therefore, lifelong follow-up in this group of patients seems to be mandatory. Extensive immunological investigations did not provide evidence for humoral mechanisms underlying the pathogenesis of this disease; T lymphocyte subsets in peripheral blood as well as functional reactivity of lymphocytes in vitro were also normal. However, none of the patients was able to mount a primary cellular immune response in vivo. On the other hand, kidney biopsy specimens obtained before the initiation of drug therapy revealed periglomerular and interstitial cellular infiltrations consisting predominantly of T lymphocytes with a ratio Leu 3a (OKT4)/Leu 2a (OKT8) of 5:1. This may indicate that a type IV (delayed-type) hypersensitivity reaction takes place in the kidney. These findings suggest that an abnormal cellular immunoreactivity plays a major role in the pathogenesis of Wegener’s granulomato

ISSN:0250-8095    

DOI:10.1159/000166898

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

Pneumococcal vaccine, 14-valent, was administered to 75 stable adult renal transplant patients on maintenance immunosuppression. 32 had undergone splenectomy prior to transplantation and 43 had not. Functional opsonizing antibody was measured by chemiluminescence methodology for types 12F and 14, contained in the vaccine, and for type 5, a control strain. Serum was examined prior to and at 1 and 6 months after vaccine injection. 33, 71, and 35% of transplant patients had preexisting antibody to types 5, 12F, and 14, respectively, as compared to 58, 87, and 68% of controls. No differences were observed in nonsplenectomized versus splenectomized patients. Following immunization, 59 and 76% of antibody-negative patients converted to positive for pneumococcus type 12F and 14. These included 70 and 70% for nonsplenectomized patients as compared to 50 and 84% for those splenectomized. Vaccination did not result in the production of opsonizing antibody for the related type 5 pneumococcus. Pneumococcal vaccine generates functional antibody and is safe in renal transplant patients.

ISSN:0250-8095    

DOI:10.1159/000166899

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

A rapid ultrafiltration technique was used to measure the free (unbound) fraction of disopyramide in serum obtained from 14 normal volunteers, 6 chronic hemodialysis patients, and 10 renal transplant recipients. The disopyramide-free fraction varied more than tenfold at a corresponding total (free plus bound) serum disopyramide concentration of 3 μg/ml and was related to the concentration of an acute-phase protein, alpha-1 -acid glycoprotein (AAG), in patient serum. Moreover, disopyramide-free fraction values were nearly twofold lower than normal in serum specimens obtained from those renal patients and transplant recipients with corresponding AAG serum concentrations greater than 100 mg/l00 ml. AAG concentrations varied tenfold in patient serum and were on average nearly three times higher than AAG concentrations in normal volunteer serum. These findings suggested that the free fraction of disopyramide and possibly other drugs which bind extensively to AAG may be lower, and the interpatient variability in drug binding may be much more pronounced in serum obtained from hemodialysis patients and transplant recipients than previously recognized

ISSN:0250-8095    

DOI:10.1159/000166900

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

Urinary oxalate excretion was measured in 101 male idiopathic calcium (Ca) stone formers studied on 3 dietary conditions (free-choice, Ca-enriched, and low-Ca diet). The population consisted of 38 normocalciuric and 63 hypercalciuric patients. Mean oxalate excretion was similar in normocalciuric and in hypercalciuric patients, on free-choice as well as on Ca-enriched diet. In both conditions the incidence of hyperoxaluria ( ≥ 435 μmol/24 h) within each group of stone formers was also similar, ranging from 11 to 22%. On low-Ca diet, however, mean oxalate excretion increased significantly (p < 0.01) in hypercalciurics but not in normocalciurics; on this diet, the incidence of hyperoxaluria was particularly high in the hypercalciurics (33%), compared with the normocalciurics (13%). On low-Ca diet, oxalate excretion was positively correlated with the estimated degree of intestinal absorption of calcium (p=0.01). These results show that among idiopathic stone formers, mild hyperoxaluria is not a rare finding and that this disorder can be encountered in each group of patients; its incidence, however, is influenced by the calcium content of the diet. On a low-Ca diet, patients with intestinal Ca hyperabsorption are particularly prone to develop hyperoxaluria, an observation which leads to question the relevance of such a dietary advice unless oxalate intake is simultaneously reduc

ISSN:0250-8095    

DOI:10.1159/000166901

出版商:S. Karger AG    

年代:1985

数据来源: Karger

摘要:

In animals with reduced renal mass increased glomerular filtration is associated with accelerated glomerular sclerosis. Whether hyperfiltration causes glomerular damage in humans is unknown. Since increased glomerular filtration occurs in obesity, the amount of glomerular sclerosis found in renal autopsy tissue from 46 patients with massive obesity was compared to that found in 46 normal body weight controls. Despite increased kidney weight and glomerular size, obese patients had the same proportion of completely sclerosed glomeruli as controls. In addition, no focal segmental glomerular sclerosis was seen in the obese group. It is concluded that patients with massive obesity have increased kidney weight and nephron size consistent with hyperfiltration. Nevertheless, massively obese patients do not appear to have increased glomerular sclerosis.

ISSN:0250-8095    

DOI:10.1159/000166902

出版商:S. Karger AG    

年代:1985

数据来源: Karger

ISSN:0250-8095    

DOI:10.1159/000166903

出版商:S. Karger AG    

年代:1985

数据来源: Karger

ISSN:0250-8095    

DOI:10.1159/000166904

出版商:S. Karger AG    

年代:1985

数据来源: Karger