Naoki Yoshiyama

Ten Years’ Survey of Dialysis-Associated Tuberculosis

Tuberculosis associated with dialysis was studied at the Renal Unit of the Tokyo Medical and Dental University and Yokosuka Mutual Aid Hospital Kidney Center, in both of which the treatments of chronic renal failure are the same. There are 12 tuberculosis patients out of 367 patients on maintenance hemodialysis from January 1967 to December 1976, an incidence of 3.3%. This was 6-16 times greater than that in the general population of this country according to yearly statistics. The characteristics of dialysis-associated tuberculosis include a high incidence of miliary tuberculosis, especially in aged patients and difficulty in establishing the diagnosis before death. Clinical features which are helpful in the early diagnosis are intermittent high fever of unknown origin, weight loss, anorexia, abnormalities of the central nervous system, erythrocyte sedimentation rate over 100 mm/h, leukocytosis and high value of the C-reactive protein. With the increasing number of dialysis patients, an increase of dialysis-associated tuberculosis is expected and this will be one of the major problems of dialysis patients in future.

KCl co-transport across the basolateral membrane of rabbit renal proximal straight tubules.

Mammalian renal proximal tubules reabsorb large amounts of chloride. Mechanisms of the transcellular chloride transport are poorly understood. To determine whether KCl co-transport exists in the basolateral membrane of mammalian renal proximal tubule, isolated rabbit proximal straight tubules (S2 segment) were perfused in vitro, and intracellular activities of potassium and chloride (aKi, aCli) were measured by double-barreled ion-selective microelectrodes. aCli did not change when basolateral membrane voltage was altered by application of a direct current through perfusion pipette. aCli changes in response to bath chloride elimination were not affected by current application as well, indicating that the basolateral chloride transport is electroneutral. An increase in potassium concentration of the bath fluid from 5 to 20 mM reversibly increased aCli by 10 mM. This response of aCli to a change in the bath potassium concentration was also observed when luminal chloride was removed, or ambient sodium was totally removed. aKi significantly decreased by 5 mM when chloride was removed from the bath. These data demonstrate the existence of an electroneutral Na+-independent KCl co-transport in the basolateral membrane of the rabbit proximal tubule. Calculated electrochemical driving force was favorable for the movement of KCl from the cell to the peritubular fluid.

Surface properties of hydroxyapatite ceramic as new percutaneous material in skin tissue

Hydroxyapatite ceramic (HAC) was studied for utilization as a percutaneous device to prevent exit-site and tunnel infection along peritoneal dialysis catheters. As a result, it was found that HAC had good compatibility with skin tissue compared with silicone rubber and glassy carbon. In the present study, the surface properties of HAC after long-term implantation in skin of dogs was evaluated by scanning electron microscopic observation, solubility and bending tests. At 12 weeks after implantation, the surface of HAC was eroded severely by body fluid or cells, and the grain boundaries were clearly relieved. Ingrowth and adhesion of collagen into the etched ditch of HAC were observed. At 12 months, the eroded surface had been tightly covered and adhered to by a collagenous layer in spite of ripping off the surrounding fibrous capsule. In solubility tests, HAC dissolved at the rate of 0.23 mg cm−2 HAC surface area per year. On the other hand, the bending strength decreased by about 10% at 4 weeks and scarcely decreased after that time. From these results, it was confirmed that the solubility of HAC produced tight contact and strong adhesion with skin tissue to prevent bacterial infection, and HAC was practical for a permanent percutaneous device.

Plasma Levels of Human Atrial Natriuretic Factor in Patients Treated by Hemodialysis and Continuous Ambulatory Peritoneal Dialysis

We measured plasma levels of immunoreactive human atrial natriuretic factor (ANF) in chronic renal failure patients treated by hemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD). Predialysis plasma ANF was significantly higher in HD patients (271.8 +/- 173.4 pg/ml) as compared to CAPD patients (81.8 +/- 80.5 pg/ml) and healthy subjects (31.5 +/- 19.8 pg/ml). Plasma volume was higher in HD patients than in CAPD patients. Plasma ANF and plasma volume showed a significant positive correlation. In HD patients, high plasma ANF value decreased significantly to a value comparable with that of CAPD patients after each dialysis. The removal rates of ANF by HD and CAPD were comparable. Ultrafiltration corresponding to 2% of body weight without dialysis also reduced plasma ANF. Thus, the difference in plasma ANF values between HD and CAPD patients seems to be mostly due to the difference in plasma volume, indicating that plasma ANF is sensitive to volume status even in chronic dialysis patients.

Long-term use of low molecular weight heparin ameliorates hyperlipidemia in patients on hemodialysis

Hyperlipidemia is one of the major risk factors for cardiovascular death in long-term hemodialysis (HD) patients. To clarify whether unfractionated heparin (UFH) contributes to the pathogenesis of hyperlipidemia, nine Type IIb, seven Type IV, and 10 normolipidemic patients, who had been dialyzed with 80.7 IU/Kg heparin, were dialyzed with 40 anti-Xa U/kg of low molecular weight heparin (LMWH) (Logiparin, Novo-Nordisk, Gentfe, Denmark) for 6 months. Seven normolipidemic patients were also dialyzed with heparin as controls. Decreases in triglyceride (TG) during HD with LMWH were significantly less than those with heparin. However, lipoprotein lipase activities (LPL) during HD with LMWH and heparin, and those before and after 6 months on LMWH, were no different. During the 6 months on LMWH, serum total cholesterol, TG, and alpha lipoprotein significantly decreased in Type IIb patients but did not change in Type IV. In contrast, beta lipoprotein slightly increased in Types IIb, IV, and normolipidemic patients who were dialyzed with LMWH but was unchanged in the controls. These observations suggest that UFH aggravates hyperlipidemia in patients, but these effects cannot be attributed to depletion of endothelial LPL liberated by UFH.

Intraglomerular Deposition of Coagulation-Fibrinolysis Factors and a Platelet Membrane Antigen in Various Glomerular Diseases

The intraglomerular location of coagulation-fibrinolysis factors (CFF) and a platelet membrane antigen (glycoprotein IIb-IIIa; GPIIb-IIIa) was determined in 101 patients with various glomerular diseases. Renal biopsy specimens were examined by immunofluorescence microscopy, using antisera against fibrinogen/fibrin reactive antigen (FRA), cross-linked fibrin degradation products (XL-FDP), fibronectin (FN), factor XIII-subunit a (F-XIIIa), plasminogen (Plg), alpha 2-plasmin inhibitor (alpha 2-PI) and GPIIb-IIIa. Intraglomerular deposits of the CFF were found at high rates in patients with IgA glomerulonephritis (GN), membranous nephropathy (MN) and lupus GN. The coexistence of deposits of these factors was ascertained by the double-staining method. The deposition rates of XL-FDP and GPIIb-IIIa were very low in patients with minimal-change nephrotic syndrome and focal glomerulosclerosis. Some cases of diabetic glomerulosclerosis (DGS) showed CFF deposition. FRA deposits associated with F-XIIIa and FN may indicate the presence of the cross-linked fibrin. Furthermore, the presence of Plg deposits together with alpha 2-PI and XL-FDP suggests the deposition of fibrin followed by fibrinolysis, but not of fibrinogen, and the coexistence of GPIIb-IIIa suggests the involvement of platelets in the reactions. These studies provide evidence that stabilized fibrin deposition with subsequent fibrinolysis and platelet activation take place in glomeruli in a fairly large proportion of patients with IgA GN, MN and lupus GN and in some cases of DGS.

Unilateral Renal Agenesis Associated with Various Metabolic Disorders in Three Siblings

Unilateral renal agenesis with impaired renal function was found in all 3 siblings of a single family, in association with various metabolic disorders such as diabetes mellitus, hyperuricemia and hyperbilirubinemia with gallstones. The present report suggests that unilateral renal agenesis could occur as a manifestation of a genetic disorder.

Uremic Galactorrhea: an Endocrine Profile

Abnormal lactation (galactorrhea) was observed in 5 female patients with renal failure. This appeared in association with amenorrhea in the terminal stage of renal failure. Lactation gradually decreas

Effects of Kinin on Electrolytes Transport and Regulation of Kininase Activity in Distal Nephron Segments of the Rat

It is generally recognized that the cortical collecting duct plays a major role in the fine control of renal sodium excretion, and thus in the regulation of extracellular fluid volume. Several lines of evidence point to the cortical collecting duct as a possible site of kinin action on sodium transport. First, both kallikrein1-3 and kininogen4 have been localized to the collecting duct system. Second, high-affinity binding sites for bradykinin have recently been localized to the cortical and outer medullary collecting ducts5. Third, kinins have a marked inhibitory effect on vasopressin-stimulated water permeability in the isolated, perfused cortical collecting duct of the rabbit. First part of our studies is to investigate whether bradykinin directly affects net sodium transport in the cortical collecting duct of the rat using the isolated, perfused tubule technique.

The dialysis memblane in long-term hemodialysis treatment.

Recent advance of materials and design for dialyser membrane made possible to achieve high dialysis efficacy and high flux. The purpose of dialysis membrane now and in the future is to refine blood biocompatibility and to get the character to remove the special substances from the blood of uremic patients. Because of the difficulties to achieve the complete biocompatibility by artificial polymers now used, it is important for us to change the idea for invention of new dialyser material of the next generation.