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K D Gardner

Publications and source records attributed to K D Gardner.

18 recordsLinked to original sources
PubMed1992

On the probability that kidneys are different in autosomal dominant polycystic disease.

We hypothesized that highly variable cyst fluid sodium concentrations are a characteristic of every kidney in autosomal dominant polycystic kidney disease (ADPKD). We added our data on sodium concentrations in 124 fluids from ten ADPKD kidneys to data published by others of concentrations in 32 fluids from five kidneys. The values ranged from 3 to 207 mEq/liter; none fell between 59 and 74 mEq/liter. Fluids were designated as low (< 60 mEq/liter; 50 fluids) or high (> 60 mEq/liter; 106 fluids) sodium fluids. Transmission electron microscopy identified differences in the depths of apical tight junctions between cells from cyst walls of 12 of the low and 10 of the high sodium fluids from two kidneys (mean +/- SE depths of 2039 +/- 74 A vs. 386 +/- 18 A respectively; P < 0.0001). When fluids were grouped by kidney of origin, six of the 15 kidneys had only high sodium fluids. The probability that chance had led to the sampling of only high sodium fluids in these organs, given that 32% of all fluids were low sodium fluids, was calculated at < 0.00015. The possibility must be considered that all kidneys are not alike in ADPKD.

Adult↗
PubMed1992

Phenotype recognition. Clinicians' contributions to molecular genetics.

Medullary cystic disease, Alport's syndrome, and autosomal dominant polycystic kidney disease are inherited renal disorders whose genetic bases are better understood because of careful clinical observation. I explore the relationships among some clinical aspects of each of these conditions, the rapidly advancing field of molecular genetics, and the ethical issues that need to be addressed before gene identification becomes too widely applied as a diagnostic tool.

Ethics, Medical↗
PubMed1991

Cytokines in fluids from polycystic kidneys.

We sought evidence of cytokine presence and interleukin-1 beta (IL-1 beta) bioactivity in 104 aerobic culture negative cyst fluids (CFs) from 13 kidneys of 13 patients with symptomatic normal to end-stage autosomal dominant polycystic kidney disease (ADPKD). ELISAs were used to detect IL-1 beta, interleukin-2 (IL-2), tumor necrosis factor alpha (TNF alpha) and stromelysin. Prostaglandin E2 (PGE2) was detected by radioimmunoassay. IL-1 beta was present in 65 of 94 (less than 20 to 419 pg/ml, TNF alpha in 54 of 75 (less than 10 to 73 pg/ml), stromelysin in 18 of 23 (less than 1.0 to 56 ng/ml), IL-2 in 7 of 23 (0.1 to 1.3 ng/ml) and PGE2 in 9 of 10 fluids (0.03 to 0.49 ng/ml). Of 51 fluids with immunoreactive IL-1 beta, 36 were mitogenic for thymocytes. IL-1 beta concentrations correlated directly with those of IL-2; IL-1 beta presence was associated with higher stimulation indices, higher mean concentrations of TNF alpha, IL-2, stromelysin, and PGE2, and with positive endotoxin assays, suggesting activation of the cytokine cascade in vivo. Cytokine, stromelysin and PGE2 concentrations did not correlate with sodium or non-sodium solute concentrations, nor with CF blood, osmolality, or endotoxin activity, indicating that differences in concentrations among fluids could not be explained by differences in water content. These data identify cytokines as candidate contributors to the morbidity and pathogenesis of ADPKD.

Adult↗
PubMed1979

Polypoid and papillary epithelial hyperplasia: a potential cause of ductal obstruction in adult polycystic disease.

In experimental models of cystic renal disease, functional studies define conditions that suggest increased resistance to outflow from dilated or cystic nephrons. Morphologically, models exhibit foci of cellular hyperplasia and micropolyp formation along outer medullary collecting tubules. Temporally, cellular proliferation precedes cyst formation. These findings in models have led to a hypothesis that polypoid hyperplasia participates in cyst formation in susceptible kidneys by increasing resistance to the outflow of tubular urine. The present study was undertaken to establish the presence, extent, and distribution of cellular hyperplasia in human adult polycystic kidney disease. Kidneys from four unrelated individuals were studied by light and by transmission and scanning electron microscopy. Foci of hocation of hyperplasia along the nephron were similar to those seen in the models. These findings delineate a heretofore unappreciated morphologic similarity between the models and human disease and add further support to the hypothesis that partial rubular obstruction participates in the pathogenesis of renal cystic disease, whether it be heritable or acquired, in animals and in man.

Animals↗
PubMed1979

Nephron obstruction in nordihydroguaiaretic acid-induced renal cystic disease.

Studies were performed to characterize conditions in rat kidneys whose nephrons were made cystic by feeding 2% nordihydroguaiaretic acid (NDGA) to the animals. Using two micropipettes, we monitored intratubular hydrostatic pressures while perfusing single surface nephrons in NDGA-exposed (5 to 7 weeks) and normal rat kidneys. The introduction of 50 nl of Ringers solution labeled with 3H-inulin at a flow rate of 25 nl/min was associated with a significant mean (+/- SEM) increase (167 +/- 61%; P less than 0.02) in pressure in cystic but not in nondilated (-0.5 +/- 27.2%) or normal (31 +/- 23%) nephrons, respectively. The relative amount of 3H-inulin excreted in 40 min from cystic (4.0 +/- 2.0%) was less than that excreted from either nondilated (19 +/- 7%; P less than 0.05) or normal (105 +/- 26%; P less than 0.01) nephrons. Intralumenal pressures in nondilated but not other nephron groups correlated with urinary flow rates (r = 0.51; P less than 0.02). Single nephron filtration rates and tubular-fluid-to-plasma 3H-inulin rations in additional rats were similar among all groups of tubules. Concluding that these data reflected increased resistance to outflow from cystic nephrons, we examined these and additional NDGA-exposed (1 to 24 weeks) kidneys. 3H-thymidine radioautography demonstrated maximum collecting tubular cell hyperplasia (13% labeling) at 2 to 3 weeks of NDGA-exposure. Microscopy and microdissection demonstrated tiny mural polyps along outer medullary segments of collecting tubules. Thirteen tubules were traced to their outlets; polyps impinging on outflow lumens were found in all 13 instances. We conclude that partial nephron obstruction exists in NDGA-exposed kidneys and that obstruction is a likely contributor to cyst formation in this model.

Animals↗
PubMed1976

Gaps--anionic and osmolal.

Gaps is a bedside diagnostic game. It is played in two versions by nephrologists. It deserves wider application by the practicing physician. The more popular version, Anion Gaps, shows the presence of undetermined anions and alerts the physician to the possibilities of laboratory error, severe derangements in serum protein metabolism, or the ingestion of certain ionic compounds that directly or indirectly alter the concentration of routinely undetermined anions. A second version, Osmolal Gaps, shows the presence of unmeasured osmoles or of increased plasma solids and can be used in a variety of clinical situations to direct attention to laboratory, error, hyperproteinemia, hyperlipidemia, or the presence of unmeasured osmoles in the serum.

Acidosis, Respiratory↗
PubMed1976

Function and structure in the diphenylamine-exposed kidney.

Standard micropuncture and microdissection techniques were used to examine the function and structure of nephrons in rats whose kidneys were made cystic by dietary exposure to diphenylamine. Heterogeneity characterized the lesion, with dilation and frank cyst formation occurring in 5-30% of nephrons. Elevated intraluminal hydrostatic pressures, occurring in the absence of increased glomerular filtration or decreased net water reabsorption, were recorded in dilated, but not in nondilated nephrons. Structural studies demonstrated communication of dilated nephrons with cysts, concretions of debris within tubular lumens, evidence of extrinsic pressure by cysts on adjacent tubules, and apparent luminal narrowing of some proximal tubules. These observations were used to explain prolonged loop of Henle transit times and occasional failure to detect [3H]inulin excretion after microperfusion into dilated tubules. It was concluded that the elevated hydrostatic pressures in the dilated nephrons of diphenylamine-exposed kidneys were the consequence of variably severe and frequently incomplete tubular occlusion. These findings support the hypothesis that cyst formation is a consequence of partial obstruction and elevated intratubular pressure in this model and perhaps in other susceptible mammalian kidneys.

Aniline Compounds↗
PubMed1976

Hereditary renal-retinal dysplasia and the medullary cystic disease-nephronophthisis complex.

Nine of 81 members of two families were found to have renal problems. Three patients in one family had renal-retinal dysplasia with probable recessive inheritance. Of the 6 patients in the second family, one received a kidney transplant from his brother who initially had no detectable renal abnormality but later developed renal failure. In this family, the mode of inheritance seems to be dominant. Hereditary renal-retinal dysplasia differs from medullary cystic disease and nephronophthisis in its pattern of uniformly recessive inheritance and its accompaniment by retinitis pigmentosa. Because genetic considerations have important implications in selection of donors for renal transplant, these entities should be considered distinct despite the similarities in their clinical and pathologic features.

Adolescent↗
PubMed1976

Juvenile nephronophthisis and renal medullary cystic disease.

In the past 30 years 238 cases have been published which describe the nephronophthisiscystic renal medulla complex. Of these, 110 are sufficiently adequate to permit detailed analyses. Both isolated and genetically transmitted cases are reported. The latter include the dominant and recessive modalities, both autosomal, and the former perhaps also X-linked. Renal disease also has been inherited as a recessive trait in association with retinal degeneration. Medullary cysts have been found in 73% of cases in which kidney tissue has been examined directly. Their presence seems to bear no relationship to the ability of involved kidneys to conserve sodium. Salt wasting is described in the presence and absence of medullary cysts. Techniques short of anatomic examination of the kidneys have rarely allowed cysts to be detected and diagnosis continues to rest on a high index of suspicion, aroused in turn by a positive family history for the disease. Arterial hypertension occurs in roughly one third of cases. Aminoaciduria is not a part of the syndrome. A defect in maximum urinary concentrating ability may be the best single early sign of involvement but data are scarce.

Adult↗
PubMed1976

Comparison of human polycystic and medullary cystic kidney disease with diphenylamine-induced cystic disease.

Because of difficulty in obtaining cystic human kidneys for functional and morphologic study, animal models are receiving increasing attention. Most prominent among them is the renal cystic disease that is induced in rats through feeding of the antioxidant, diphenylamine, The present study examined the morphology of adult polycystic and medullary cystic kidney disease in man using scanning electron microscopy and compared them with diphenylamine-induced cystic kidney disease in rats. Diphenylamine nephropathy was induced by feeding rats 1 per cent diphenylamine for 12 to 18 months. All types of cystic disease showed changes in the renal corpuscles, including dilation of Bowman's space, podocyte fusion and degeneration, and basement membrane thickening. Cysts were noted along the entire nephron in polycystic and diphenylamine-induced cystic disease but only along the collecting ducts in medullary cystic disease. Cysts in polycystic disease were large and lined by flattened epithelium. Collecting duct cysts in diphenylamine cystic disease were lined by cells of irregular size and shape suggestive of cell hypertrophy and/or hyperplasia, whereas cysts of medullary cystic disease were lined by flattened epithelium except where the nephron entered or left the cyst. Cast material was generally found in the cysts of diphenylamine-induced and polycystic kidney disease but not medullary cystic disease. Atrophic glomeruli and tubules were found in all three diseases. Complete tubular obstruction was found in none; however, larger cysts frequently impinged on adjacent tubules and narrowed their lumina. The results of this study show that, in the terminal stages, cellular as well as gross morphologic differences exist between polycystic and medullary cystic kidney disease and that diphenylamine-induced cystic disease more closely resembles human polycystic than medullary cystic kidney disease.

Aniline Compounds↗
PubMed1975

Potassium. The intracellular cation.

Normally the concentration of potassium in the extracellular space is maintained within relatively narrow bounds; in disease, these boundaries may be exceeded. Hyperkalemia and sometimes hypokalemia must be considered medical emergencies, to be treated promptly, effectively, and appropriately.

Bicarbonates↗