The outcomes of kidney transplantation in hepatitis B surface antigen (HBsAg)-negative recipients receiving graft from HBsAg-positive donors: a retrospective, propensity score-matched study.

The outcomes of kidney transplantation (KT) from hepatitis B surface antigen-positive [HBsAg(+)] donors to HBsAg(-) recipients remain inconclusive, possibly due to substantial differences in methodological and statistical models, number of patients, follow-up duration, hepatitis B virus (HBV) prophylactic regimens and hepatitis B surface antibody (anti-HBs) levels. The present retrospective, longitudinal study (clinicaltrial.gov NCT02044588) using propensity score matching technique was conducted to compare outcomes of KT between HBsAg(-) recipients with anti-HBs titer above 100 mIU/mL undergoing KT from HBsAg(+) donors (n = 43) and HBsAg(-) donors (n = 86). During the median follow-up duration of 58.2 months (range 16.7-158.3 months), there were no significant differences in graft and patient survivals. No HBV-infective markers, including HBsAg, hepatitis B core antibody, hepatitis B extracellular antigen and HBV DNA quantitative test were detected in HBsAg(+) donor group. Renal pathology outcomes revealed comparable incidences of kidney allograft rejection while there were no incidences of HBV-associated glomerulonephritis and viral antigen staining. Recipients undergoing KT from HBsAg(+) donors with no HBV prophylaxis (n = 20) provided comparable outcomes with those treated with lamivudine alone (n = 21) or lamivudine in combination with HBV immunoglobulin (n = 2). In conclusion, KT without HBV prophylaxis from HBsAg(+) donors without hepatitis B viremia to HBsAg(-) recipients with anti-HBs titer above 100 mIU/mL provides excellent graft and patient survivals without evidence of HBV transmission.

Angiotensin II receptor blocker partially ameliorated intrarenal hypoxia in chronic kidney disease patients: a pre-/post-study.

Chronic intrarenal hypoxia has been regarded as a pathogenic factor of progressive renal damage. However, the lack of available human data has impeded the progress in this field. In this work, blood oxygen level-dependent magnetic resonance imaging was used to determine intrarenal oxygen status pre- and post-angiotensin receptor blockade (olmesartan) treatment in normal subjects, diabetic chronic kidney disease (CKD) patients and non-diabetic CKD patients. The mean R2*, which represents intrarenal oxygenation, was significantly lower in the control group than in the CKD group (12.42 ± 0.53 /s vs 18.89 ± 3.15 /s, P < 0.01), indicating the presence of intrarenal hypoxia in the CKD patients. The olmesartan treatment induced a 16.2 ± 7.7% decrement of the mean R2* in CKD patients, suggesting that this drug had an intrarenal hypoxia ameliorating effect.

A novel simple hemoglobin dilution technique to measure hemodialysis vascular access flow.

Measurement of the vascular access flow rate (Q(a)) is a widely accepted method for surveillance and predicting access failure. Among current practical methods, the ultrasound dilution technique is standard, but this requires a costly device available in few hemodialysis (HD) centers. Here, we devised a simple hemoglobin dilution technique to accurately measure Q(a) without the need for any special machines. Before HD, values of Q(a) were determined in each of 30 patients by hemoglobin dilution and then, in the same session, by ultrasound dilution. There was a significant correlation between the two techniques using automated hemoglobin and hematocrit or centrifuge-measured hematocrit levels to calculate HD fluid-derived Q(a) values. Our study shows that the HD dilution technique, using no special device, is economical, highly accurate, and easy to perform, and can be used as an alternative to standard ultrasound dilution for vascular access surveillance.

A prevalence of posttransplantation cancers compared with cancers in people with human immunodeficiency virus/acquired immunodeficiency syndrome after highly active antiretroviral therapy.

BACKGROUND: Organ transplant recipients and human immunodeficiency virus & acquired Immunodeficiency Syndrome (HIV/AIDS) patients have immune deficiencies that are possible mechanisms to develop malignancy. The type of cancers associated with these 2 conditions might elucidate this premise. AIM: Our aim was to compare prevalence and type of cancers between kidney transplant recipients and patients with HIV/AIDS. PATIENTS AND METHODS: We retrospectively reviewed 344 patients who underwent kidney transplantation from 1973 to 2007 compared them with 863 subjects with HIV/AIDS at the HIV-Netherlands/Australia/Thailand Research Collaboration (HIV-NAT) from 1997 to 2007. AIDS-defining cancers were excluded from the analysis. We compared the relative tumor risk with the age- and gender- matched general population of metropolitan Bangkok. RESULTS: The overall cancer risk for kidney transplant recipients (standardized incidence ratio [SIR] = 4.21) was comparable with HIV-infected patients (SIR = 3.88). Uroepithelial cancer was the most prevalent type in kidney transplant recipients, whereas cervical cancer was the most common malignancy in HIV-infected patients. The risks of developing hepatoma and non-Hodgkin's lymphoma were comparable between the groups. CONCLUSION: Kidney transplant recipients and HIV-infected patients show increased overall risks of certain types of cancers.

De novo sirolimus-based regimen in Thai renal transplant recipients.

BACKGROUND: Calcineurin inhibitor (CNI) toxicity is a common cause of chronic allograft nephropathy. Although de novo sirolimus (SRL) with CNI minimization may provide better graft function, studies in Asian recipients are lacking. AIM: We sought to determine the 1-year outcomes of renal transplant patients who received a de novo SRL-based regimen with CNI minimization. PATIENTS AND METHODS: A single-center, prospective study of de novo SRL-based, reduced-dose cyclosporine regimen was performed from 2004 to 2007. The control group was a historical cohort of a cyclosporine-based regimen (cyclosporine, prednisolone, and mycophenolate mofetil). The 1-year outcome parameters included renal function, rate of acute rejection, biopsy-proven CNI toxicity, graft and patient survivals. RESULTS: The SRL-based regimen achieved 100% 1-year graft and patient survivals. The renal function was comparable between the SRL-based and CNI-based regimens (serum creatinine 1.32 +/- 0.45 and 1.45 +/- 0.43 mg/dL; P = .27). The rate of biopsy-proven acute rejection was comparable (9.5% and 13%; P = .68). The SRL-based regimen had a higher rate of biopsy-proven CNI toxicity (28.5% and 9.7%; P = .03). CONCLUSIONS: De novo SRL-based regimen with CNI minimization provides excellent transplant outcomes. The strategy to minimize or withdraw CNIs may achieve excellent graft function. A prospective study targeting lower CNI trough levels in Asian transplant recipients is required.

Regulation of collecting tubule adenosine triphosphatases by aldosterone and potassium.

To examine the precise role of potassium and aldosterone on acid-base composition and on collecting tubule ATPases, glucocorticoid-replete adrenalectomized rats were replaced with zero, physiological, or pharmacological doses of aldosterone and were fed varying potassium diets to produce hypokalemia, normokalemia, or hyperkalemia. Radiochemical measurement of ATPase activities showed that collecting tubule H/K-ATPase changed inversely with potassium and not with aldosterone whereas H-ATPase changed directly with aldosterone but not with potassium. When both enzymes changed in the same direction, alterations in acid-base composition were profound; however, when these two acidifying enzymes changed in opposite directions or when only one enzyme changed, the effect on acid-base balance was modest. Serum bicarbonate was approximately 45 meq/liter when aldosterone was high and potassium was low; it was only 29 meq/liter when aldosterone was high but potassium was normal or when aldosterone was normal and potassium was low. Our observations may help explain the metabolic alkalosis of primary aldosteronism in which aldosterone excess and hypokalemia are combined and the metabolic acidosis of aldosterone deficiency in which hypoaldosteronism and hyperkalemia are paired. The present study also demonstrated that aldosterone plays the major role in controlling Na/K-ATPase activity in cortical collecting tubule. Hypokalemia stimulates Na/K-ATPase activity in the medullary collecting tubule; this stimulatory effect of hypokalemia supports the hypothesis that the enzyme is present on the apical membrane at this site.

Antioxidative effects of erythropoietin.

Erythropoietin (EPO) has been shown to exert cytoprotective effects on erythroid progenitor cells as well as various non-erythroid cells. Experimental studies have demonstrated the renoprotective effects of EPO in various acute and chronic renal injury models. These protective effects have been largely attributed to antiapoptotic signalings of EPO. However, injured cells undergoing apoptosis are generally too severely damaged to function properly. Therefore, simply corrupting apoptotic pathway is unlikely to be an effective strategy, because the remaining damaged cells may not function appropriately, or they may eventually undergo necrotic cell death. Recent evidences suggest that EPO also provides cytoprotection by ameliorating oxidative stress, the principal cellular insult. EPO may exert its antioxidative effects directly by exploiting intracellular antioxidative mechanisms such as heme oxygenase-1 and glutathione peroxidase. In addition, EPO may act indirectly by inducing iron depletion and thereby inhibiting iron-dependent oxidative injury. Increasing red blood cells by EPO may also indirectly reduce cellular oxidative stress, as red blood cells are loaded with a substantial amount of antioxidative enzymes. Further investigation regarding the mechanisms of cellular antioxidative responses to EPO would provide a better insight to cytoprotective action of EPO, and would support the development of better cytoprotective drugs in the near future.

Comparison of middle-molecule clearance between convective control double high-flux hemodiafiltration and on-line hemodiafiltration.

Hemodiafiltration (HDF) is now a well-recognized treatment modality for end-stage renal disease (ESRD) patients. It provides superior characteristics over conventional hemodialysis in many respects. On-line HDF, however, which has been mainly used in clinical practice, requires a special machine. Interestingly, the recently innovated convective-control double high-flux hemodiafiltration (CC-DHF) machine can provide HDF treatment with an adjustable convection rate by using the conventional volume-controlled dialysate flow hemodialysis machine in a modified way. The present study was conducted to compare the efficacy of CC-DHF compared to on-line HDF in terms of middle and small solute clearances in 12 stable, chronic hemodialysis patients who underwent hemodialysis three times a week for at least 6 months. The results showed that the beta 2-microglobulin (beta 2M) removal represented by the beta 2M clearance in CC-DHF was comparable to that in on-line HDF (112.4+/-17.0 vs. 119.4+/-15.5 ml/min respectively, NS). Also, the beta 2M reduction ratio in the CC-DHF group did not differ from the on-line HDF group (85.5+/-4.2% vs. 86.1+/-6.7%, NS). With regard to small solute clearances, the values of single-pool Kt/V and phosphate clearance did not differ between CC-DHF and on-line HDF groups. In conclusion, CC-DHF provides removal of beta 2M and small molecule uremic toxins that is comparable to on-line HDF. An on-line HDF machine may not be available in all hemodialysis centers, whereas CC-DHF can be easily set up, with proper precautions regarding the fluid quality. Therefore, CC-DHF can provide the benefits of convective therapy to patients in situations where use of an on-line HDF machine is limited.

Correlations between antinucleosome antibodies and anti-double-stranded DNA antibodies, C3, C4, and clinical activity in lupus patients.

OBJECTIVE: To examine the correlations between antinucleosome antibodies and anti-double-stranded (ds) DNA antibodies, complement (C) 3 and 4 levels, and clinical activities in SLE patients. METHODS: Antinucleosome antibodies and anti-dsDNA antibodies were detected by enzyme-linked immunosorbent assays (ELISA). The levels of C3 and C4 were measured by nephelometry. Clinical activities were determined by SLE Disease Activity Index (SLEDAI). RESULTS: Of 65 SLE patients, the prevalence of antinucleosome antibodies were higher than anti-ds DNA antibodies (52.3 vs 36.9%, respectively, p < 0.05). Similar results were obtained in 45 active SLE patients, 64.4% for antinucleosome antibodies and 46.7% for anti-ds DNA antibodies. Of 34 patients lacking anti-ds DNA antibodies, 16 (47.1%) were shown antinucleosome antibodies. Activity of antinucleosome antibodies was significantly correlated with the SLEDAI scores and inversedly correlated with the C3 levels but not with the C4 levels. CONCLUSION: Antinucleosome antibodies could be one of the earliest and most sensitive markers in diagnosis of SLE, particularly in anti-dsDNA antibodies-negative patients. More importantly, antinucleosome antibodies is correlated with clinical activities and C3 levels.

Falciparum malaria and the kidney: a model of inflammation.

Renal and renal-related disorders commonly occur in infection with Plasmodium falciparum, which can cause fluid and electrolyte disorders, glomerulonephritis, and acute renal failure (ARF). It appears that ARF and other life-threatening complications in falciparum malaria are not directly caused by the parasite itself but are the result of interaction of mechanical, immunologic, and humoral components. P. falciparum-infected erythrocytes impair microcirculation and cause hemolysis. Glycosylphosphatidylinositol moieties covalently linked to the surface antigens of falciparum malarial parasites appear to act like endotoxin. Glycosylphosphatidylinositol, via CD14, which is a receptor on monocytes, stimulates monocytes to release tumor necrosis factor, which in turn enhances synthesis of various cytokine cascades and mediators. Besides contributing to ARF, these mediators also cause changes in blood volume status. The degree of vasodilatation caused by vasodilating mediators varies with the severity of infection. Increased vascular permeability by the mediators occurs in severe infection, which results in hypovolemia and contributes to ARF. Although the cornerstone of treatment of malaria still is antimalarial drugs, several new modalities of treatment targeting toxin, signal transduction, mediators, and cytokines have great potential.

Environmental distal renal tubular acidosis in Thailand: an enigma.

Distal renal tubular acidosis is a common health problem in northeastern Thailand, with the population background of the low potassium intake, low urine citrate, and decreased red blood cell Na-K adenosine triphosphatase (ATPase) activity and the environment of the high soil vanadium. The disease is usually seen in the people with low socioeconomic status in summer. The patients have decreased gastric acidity and low urine potassium. There are varying degrees of renal function from normal to impairment. Gastric hypoacidity is an important clue. Defects in H-K ATPase and anion exchange (AE2) mechanism are considered. The urine vanadium is higher in the patients than that of normal rural northeastern villagers. Inhibition of H-K ATPase by vanadium seems possible and requires more supporting evidence. AE1 gene mutation is noted in few patients. The cause of dRTA is not apparent. The AE2 gene and H-K ATPase gene remain to be studied. Both environmental and genetic factors could contribute to the pathogenesis of the disease.

Potassium depletion: renal membrane lipid metabolism and Na/H exchanger abundance in aged F344 x BNF1 rats.

Potassium depletion (-K) is a common electrolyte abnormality in elderly humans, occurring after diuretic use or poor oral intake. We hypothesized that aging would result in an increase in renal membrane lipid metabolism in both control and -K, and that the Na/H exchanger's protein abundance to -K would be blunted. Young and senescent non-obese male Fisher 344 x Brown-Norway F1 rats (F344 x BNF1) were fed either a normal or a K-deficient diet for 7 days. At 24-h, 32P incorporation was measured for renal cortical brush-border (BBM) and basolateral membrane (BLM) lipid metabolism. All -K animals showed a reduction in total body potassium stores, a fall in plasma aldosterone, a urinary concentrating defect, and an increase in plasma cholesterol and urine ammonium excretion (p < .001). In BBM of both age groups, -K increased phosphatidylserine, sphingomyelin, phosphatidylcholine, and phosphatidylethanolamine concentrations, but 32P incorporation fell. In BLM of young K-depleted rats, however, only phosphatidylcholine concentration increased. In the hypokalemic aged rats, the concentration of all BLM phospholipids rose, whereas 32P incorporation fell. In both membranes, cholesterol concentration and the molar ratio of cholesterol to total phospholipid increased with -K (p < .05). Potassium depletion caused brush-border membrane NHE-3 protein abundance to rise, but only in the young rats. Neither NHE-3 nor basolateral NHE-1 protein abundance was affected in aged animals with -K. These results provide the first evidence, in non-obese aged rats, that selective age-associated modifications occur in membrane lipid metabolism and membrane transporter protein abundance during -K. That aging causes a maladaptive response in brush-border NHE-3 protein expression may have important implications for elderly humans, particularly if they are given diuretics and become potassium depleted.

Diseases of renal adenosine triphosphatase.

Most renal transport is a primary or secondary result of the action of one of three membrane bound ion translocating ATPase pumps. The proximal tubule mechanisms for the reabsorption of salt, volume, organic compounds, phosphate, and most bicarbonate reabsorption depend upon the generation and maintenance of a low intracellular sodium concentration by the basolateral membrane Na-K-ATPase pump. The reabsorption of fluid and salt in the loop of Henle is similarly dependent on the energy provided by Na-K-ATPase activity. Some proximal tubule bicarbonate reabsorption and all distal nephron proton excretion is a product of one of two proton translocating ATPase pumps, either an electrogenic H-ATPase or an electroneutral H-K-ATPase. In this article, the authors review the biochemistry and physiology of pump activity and consider the pathophysiology of proximal and distal renal tubular acidosis, the Fanconi syndrome, and Bartter's syndrome as disorders of ATPase pump function.

Pharmacokinetics of intraperitoneal cefazolin and gentamicin in empiric therapy of peritonitis in continuous ambulatory peritoneal dialysis patients.

OBJECTIVE: The aim of this study was to measure and evaluate the appropriateness of the actual concentrations of serum and dialysate cefazolin and gentamicin in Thai continuous ambulatory peritoneal dialysis (CAPD) patients treated following the International Society for Peritoneal Dialysis (ISPD) 1996 recommendations for the empiric therapy of CAPD-related peritonitis. DESIGN: Prospective and descriptive study. SETTING: Institutional level of clinical care. PATIENTS: CAPD-related peritonitis patients were diagnosed by dialysate effluent white cell count of more than 100/mm3 and polymorphonuclear leukocytes of at least 50%. There were 18 patients, all at least 15 years of age, entered; all completed the study. INTERVENTION: In accordance with the ISPD 1996 recommendations, the antibiotic regimen included continuous intraperitoneal (IP) cefazolin and once-daily IP aminoglycoside. Cefazolin was administered as loading and continuous maintenance doses of 500 and 125 mg/L dialysate, respectively. Gentamicin, 0.6 mg/kg body weight, was given IP once daily. Duration of treatment was 120 hours. MAIN OUTCOME MEASURES: Serum and dialysate effluent samples of the 18 CAPD patients with peritonitis were measured and used for the synthesis of pharmacokinetic equations that could predict drug concentrations at any treatment time. RESULTS: Following administration according to the ISPD 1996 treatment recommendations, serum cefazolin reached levels higher than the recommended levels (8 microg/mL) at 3.3 minutes after drug administration, and persisted through the 5-day duration of the study. Dialysate cefazolin levels during the studied period also were persistently higher than the recommended values. The peak serum gentamicin levels were lower than the suggested values of 4 microg/mL, whereas the trough serum gentamicin levels were higher than the minimal toxic concentrations (2 microg/mL). Dialysate gentamicin levels were higher than therapeutic concentrations for only 4.75 hours in each day. It was difficult, using pharmacokinetic studies, to adjust the dosage regimen of gentamicin to achieve appropriately therapeutic levels in both serum and dialysate. CONCLUSIONS: The ISPD 1996 recommended dosage of continuous IP cefazolin could be appropriate for the treatment of CAPD-related peritonitis. Once-daily IP gentamicin administration, however, has less therapeutic benefit and should be re-evaluated.

Monitoring of T-cell subsets in patients treated with anti-CD 25 antibody.

Daclizumab and basiliximab, the antibodies to the interleukin-2 receptor (anti-IL-2R), decrease the incidence of acute rejection in renal transplantation. However, prolonged blockade of IL-2 receptor (IL-2R:CD25) may hamper apoptosis of reactive T-cell clones and thus may obstruct tolerance induction. We determined the effect of varying doses of anti-IL-2R on the number of CD3+CD25+ cells as an index of CD 25 blockade. The number of CD3+CD25+ cells was determined in four groups of induction therapies: no antibody induction; two doses of 50 or 25 mg daclizumab on day 0 and day 14; and two doses of 20 mg basiliximab at day 0 and day 4 (n=10, 24, 10, and 10, respectively). The number of CD3+CD25+ cells were monitored in whole blood before antibody infusion as well as 24 hours thereafter and weekly after transplantation. With two doses of 50 mg daclizumab, two doses of 25 mg daclizumab, and two doses of 20 mg basiliximab, the expression of CD3+CD25+ cells was completely suppressed for 12, 10, and 12 weeks posttransplantation, respectively. The reappearance of CD3+CD25+ cells above the baseline for each induction regimen was: 17 weeks for two doses of 50 mg daclizumab, 11 weeks for two doses of 25 mg daclizumab, and 13 weeks for two doses of 20 mg basiliximab. Monitoring of CD3+CD25+ cells may be utilized to tailor anti-IL-2R administration at a minimal dosage, yet retaining adequate IL-2R blockade for at least 3 months posttransplantation.

Convective-controlled double high flux hemodiafiltration: a novel blood purification modality.

Convective-controlled double high flux hemodiafiltration (CC-DHF) was set-up using two high flux dialyzers. The convection occurred in the first while the fluid replacement took place in the second dialyzer. The system of CC-DHF basically resembled that of hemodiafiltration. CC-DHF was performed in 9 chronic hemodialysis Thai patients who had been treated with high flux hemodialysis for at least 6 months. When compared with high flux hemodialysis, CC-DHF could provide higher Kt/Vurea (2.4+/-0.4 vs. 2.0+/-0.4, p<0.05) and beta2-microglobulin clearance (106.2+/-15.4 vs. 48.9+/-6.1 ml/min, p<0.01). Following 6-month therapy of CC-HDF, the predialysis beta2-microglobulin levels were reduced by 12.7% while the values of Kt/Vurea were consistently higher than 2.7. The quality of life consistently improved during the 6 months of CC-DHF treatment. There were no differences in clinical and technical complications between CC-DHF and high flux hemodialysis. In conclusion, CC-DHF could provide performance comparable to hemodiafiltration without the need for expensive hemodiafiltration machines.

Hepatitis virus and kidney.

Hepatitis A, B and C viruses are major causes of viral hepatitis in human. These infectious agents not only damage liver parenchyma but can also affect renal parenchyma. Hepatitis A virus could produce acute renal failure in a similar fashion to hepatorenal syndrome. Several lines of evidence have shown that chronic hepatitis B virus-infected patients could develop immune complex glomerulopathy. There are convincing data which incriminate hepatitis C virus as the proximate aetiology of certain forms of glomerulonephritis. In post-renal transplanted patients, hepatitis B and C virus could cause increased morbidity and mortality from chronic viral hepatitis. Whether renal transplantation should be performed, either as a donor or as a recipient, in subjects infected with hepatitis B or C virus, is still an issue of controversy.

Life-long food restriction prevents renal membrane lipid deposition and lowers renal work in rats.

Renal cortical brush-border (BBM), basolateral membrane (BLM), and medullary plasma membrane (mPM) preparations were analyzed to assess the effects of life-long food restriction in aged rats on membrane lipid content. Young male Fischer 344 x Brown-Norway F1 rats consumed food ad libitum (young AL) or were food-restricted (FR, 60% of AL consumption) for either 6 weeks (young FR) or until the age of 30 months old (old FR). Senescent FR rats had 50 per cent decreases in fractional excretion of Na and K (p < 0.001) as compared with the young AL rats. Long-term FR reduced phosphate and titratable acid excretion by 80 per cent (p < 0.001). These values were not significantly different from those observed in young rats during 6 weeks of FR. Food restriction decreased renal Na, K-ATPase activity by 50 per cent (p < 0.001) in both old and young FR animals. Reduction of food intake, in old and young rats, decreased all BBM phospholipid concentrations (phosphatidylserine, phosphatidylcholine, phosphatidylethanolamine, and sphingomyelin) by 50 per cent than in the AL rats (p < 0.001). In BLM, chronic FR resulted only in lower phosphatidylcholine concentration (by 21%, p < 0.05) while phosphatidylethanolamine was increased approximately 80 per cent (p < 0.001). Total phospholipid content in mPM was progressively decreased by 23 per cent (p < 0.05) in the young FR group to be 55 per cent (p < 0.001) in the old FR rats. Cholesterol content was reduced in BBM and mPM by 38 per cent and 25 per cent (p < 0.05), respectively, during long-term FR. Both total phospholipid and cholesterol contents detected in mPM of the old FR rats were significantly lower than those obtained from the young FR animals (by 42%, p < 0.001 and 12%, p < 0.05, respectively). Plasma glucose, blood urea nitrogen, and body weight maintained at significantly lower levels during chronic FR. That life-long FR could prevent renal membrane lipid deposition and could lower renal work may explain the mechanisms that FR can delay the onset and diminish the severity of age-associated renal diseases.

Exchange transfusion in severe falciparum malaria: a simple method modified from hemodialysis circuit.

We set up a simple extracorporeal circuit, modified from the extracorporeal method generally used in conventional hemodialysis, for exchange transfusion. Temporary vascular access was used in exchange transfusion for both draining the infected blood and infusion of the freshly non-infected blood. This method of exchange transfusion was performed in 3 severe complicated falciparum malaria patients who had a percentage of parasitemia of 80, 40, and 35. The magnitude of parasitemia decreased immediately to less than one per cent and this value persisted twenty-four hours after the procedure. No complications of exchange transfusion were detected in all patients. Erythrocyte morphology determined by scanning electron microscopy was unaltered by exchange transfusion. Because of the simplicity, the effectiveness, and the safety of the procedure, this extracorporeal circuit modified from hemodialysis circuit would be a more beneficial exchange transfusion method in the treatment of severe complicated falciparum malaria than the manually-performed one.

Pharmacokinetic studies of cyclosporin in Thai kidney transplantation patients.

Pharmacokinetic studies were performed in 10 Thai patients with kidney transplantation who received microemulsion formulation (Neoral) of cyclosporin A (CsA) twice daily. No agents having pharmacokinetic effect on CsA had been used in these patients. The mean values of 12-h AUC (area under the concentration-blood curve) were 4603.63 +/- 344.61 ng x h/ml. CsA concentrations at 2 hours after dosing had the best value of correlation coefficient with the 12-h AUC. Abbreviated AUC could be calculated by stepwise multiple linear regression analysis and linear trapezoidal rule. The latter is more simple and superior to the former one.