High-dose azathioprine pulse therapy as a new treatment option in patients with active Wegener's granulomatosis and lupus nephritis refractory or intolerant to cyclophosphamide.

The objective of this study was to evaluate the feasibility and safety of high-dose azathioprine pulse (HAP) therapy in the induction of remission in patients with active Wegener's granulomatosis (WG) or progressive lupus nephritis (LN) refractory to or intolerant of cyclophosphamide. Four patients with antineutrophil cytoplasmic antibody (ANCA)-associated WG and two patients with progressive LN were treated with HAP (1200-1800 mg) applied monthly as continuous intravenous infusions at 50 mg/h. Patients received a total of 50 courses of intravenous azathioprine (AZA) therapy. Disease activity was assessed using the Birmingham Vasculitis Activity Score (BVAS) and the Systemic Lupus Erythematosus Activity Index (SLEDAI). As only partial remission was induced in patients with progressive LN on this regimen, an additional 18 cycles were applied in these patients in which oral AZA at 100 mg/day in weeks 2 and 3 was added between two intravenous courses. A hereditary defect in thiopurine methyltransferase activity was excluded before initiation of treatment. High-dose azathioprine pulse and the intensified HAP treatment were well tolerated. Complete remission was achieved in two patients with WG suffering from three relapses of disease on application of 2-6 courses of HAP. Remission was maintained for 16-24 months. The remaining two patients with WG were withdrawn after 2-3 courses due to unchanged disease activity. In two patients with LN, partial remission was noted on 6-9 courses of HAP; however, the patients relapsed despite therapy with methotrexate and mycophenolate mofetil. The intensified HAP regimen led to partial or complete remission in both LN patients which was confirmed by sequential renal biopsies. Our results suggest that HAP therapy represents a well-tolerated regimen in patients with active WG and LN intolerant of or refractory to cyclophosphamide. As partial or complete remission was observed in four of six patients, further studies seem warranted to assess clinical efficacy in these patients.

Limited T-cell repertoire in renal allograft and allogeneic melanoma transmitted by the graft.

In a patient with metastatic melanoma transmitted by the renal allograft, HLA serves as an alloantigen per se and is associated with tumor antigens at the same time. The influence of this antigeneic pattern on the Vbeta T-cell repertoire in an allogeneic melanoma, allograft, and peripheral blood mononuclear cells (PBMC) was assessed by polymerase chain reaction. Vbeta13.1 and 19 were found in both the melanoma and the graft. Vbeta14 was detected only in the melanoma and Vbeta6 was detected only in the kidney. PBMC revealed an unrestricted Vbeta pattern. Markers for cytotoxic activity of T cells--granzyme B and perforin--were not expressed during immunosuppressive therapy as clinically reflected in a nonrejecting allograft and in a progressing melanoma. In vitro PBMC proliferated to recombinant interleukin-2, whereas recombinant interferon-gamma did not augment this response. Initiation of immune therapy, in addition to discontinuation of immunosuppression, might support the rejection of the allogeneic tumor by dominant Vbeta T cells.

Pharmacokinetics of omega-3-fatty acids during ingestion of fish oil preparations.

An in vivo comparison of three dosages (3 g, 6 g, 12 g) of two different fish oil preparations in terms of plasma concentrations of their major active components eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) was performed. The plasma accumulation was measured during 28 days of ingestion and an equally long wash out period. Data were scrutinized for bioavailability in order to distinguish between the efficiency of the two preparations. Rapid increases in EPA and DHA plasma concentrations can be demonstrated at all dosages during a 28-day ingestion period. EPA accumulated more during ingestion of high than of low dosages of fish oil. DHA revealed almost identical increases and peak values in plasma concentrations in all subgroups. The present data demonstrate dose dependent increases of EPA concentrations whereas DHA plasma concentrations are comparable in all dosages investigated. Measurable EPA and DHA plasma concentration levels are inappropriate means to explain clinical effectiveness. These results were found in both commercially available fish oil preparations. Direct comparison of both preparations revealed no differences in bioavailability.

Enalapril and losartan augment endogenous nitric oxide release in Takayasu's arteritis--a case report.

Prognosis in Takayasu's arteritis is limited owing to renovascular hypertension. The authors report a patient with Takayasu's arteritis who had been unilaterally nephrectomized and presented with malignant hypertension due to renal artery stenosis. Hypertension was refractory to conventional antihypertensive treatment, and stenosis was not accessible by interventional angioplasty. Initiation of enalapril and losartan therapy was successful in improving blood pressure without deterioration of renal function due to ischemic failure. Antihypertensive treatment resulted in dramatically stimulated endogenous nitric oxide (NO) synthesis, while elevated plasma endothelin-1 levels were unchanged. Renovascular hypertension in Takayasu's arteritis is associated with an imbalance of vasoconstrictor peptide endothelin-1 and vasodilator peptide NO. Successful treatment of hypertension by enalapril or losartan results in improved endogenous NO synthesis, which putatively counterbalances excessive vasoconstrictor actions and may retard the progression of renal failure.

Correlation of beta-2-microglobulin concentration changes to changes of distribution volume.

Plasma and ultrafiltrate beta-2-microglobulin (B2M) concentrations were determined during hemofiltration (HF) and hemodialysis (HD) in order to evaluate elimination kinetics of B2M. Calculations were done on the basis of plasma-water-concentrations (PWC). Elimination of B2M during HF follows first order kinetics (r = 0.97) and the volume of B2M distribution was calculated to be 17 +/- 2% of body weight. This reflects extracellular volume (ECV). Changes of ECV in HD were induced by weight loss and further provoked by fluid shifts from intra- to extracellular volume and vice versa induced by varying dialysate sodium concentration. These ECV changes were followed by determining inuline in plasma and total dialysate. Changes of B2M concentration correlate well to changes of ECV (r = 0.98). Thus intratreatment concentration changes of B2M in cuprophane dialysis reflect simultaneous changes of B2M distribution volume. This does not exclude the possibility of B2M generation stimulated by dialysis, but proving such effects in vivo will be difficult because of multiple variants, that must be controlled.

[Acute renal failure associated with malignant hypertension]. / Akutes Nierenversagen bei maligner Hypertonie.

HISTORY AND CLINICAL FINDINGS: A 37-year-old woman was referred to the interdisciplinary emergency room with a high blood pressure and headaches. She complained about nausea and vomiting. She has been treated for hypertension for approximately 9 years in an outpatient clinic. INVESTIGATIONS: The patient's blood pressure was elevated up to 248/132 mm Hg. Emergency laboratory test revealed high blood creatinine (19,29 mg/dl) and blood urea nitrogen (365 mg/dl) along with the decreased haemoglobin concentration and normal thrombocytes. Urinalysis showed a mild hematuria and proteinuria. The CT-scan and sonography of the abdomen showed no relevant renal artery stenosis or any relevant intestinal organ damages. TREATMENT AND COURSE: An immediate antihypertensive medication was started in the emergency room, which resulted in a gradual decrease of blood pressure. Due to hypertension-induced acute renal failure, a hemodialytic treatment was initiated. After several sessions of hemodialysis, the levels of blood urea nitrogen and creatinine gradually decreased but remained elevated. The patient was included into the renal transplantation program due to the anuric renal failure. CONCLUSIONS: Acute renal failure associated with very high blood pressure and retinal bleedings is characteristics of malignant hypertension resulting frequently from pre-existing essential hypertension. In addition, uremia is a major cause of mortality in malignant hypertension. Excessive arterial pressure leads to endothelial damage of arterioles and capillaries. The ischemic collapse of glomerula promotes further irreversible renal injury, and eventually leads to a long-term hemodialysis or renal transplantation.

Inhibition of stomatal opening in sunflower leaves by carbon monoxide, and reversal of inhibition by light.

When leaves of Helianthus annuus, whose stomates had been opened in the dark in the absence of CO2, were exposed to 25% carbon monoxide (CO), stomatal conductivity for water vapor decreased from about 0.4 to 0.2 cm·s(-1). The CO effect on stomatal aperture required a CO/O2 ratio of about 25. As this ratio was decreased the stomata opened, indicating that inhibitio of cytochrome-c oxidase by CO is competitive in respect to O2. Photosynthetically active red light was unable to reverse CO-induced stomatal closure even at high irradiances, when CO2 was absent. When it was present, stomatal opening was occasionally, but not consistently observed. Carbon monoxide did not inhibit photosynthetic carbon reduction in leaves of Helianthus.In contrast to red light, very weak blue light (405 nm) increased the stomatal aperture in the presence of CO. It also increased leaf ATP/ADP ratios which had been decreased in the presence of CO. The blue-light effect was not related to photosynthesis. Neither could it be explained by photodissociation of the cytochrome a 3-CO complex which has an absorption maximum at 430 nm. The data indicate that ATP derived from mitochondrial oxidative phosphorylation provides energy for stomatal opening in sunflower leaves in the dark as well as in the light. Indirect transfer of ATP from chloroplasts to the cytosol via the triose phosphate/phosphoglycerate exchange which is mediated by the phosphate translocator of the chloroplast envelope can support stomatal opening only if metabolite concentrations are high enough for efficient shuttle transfer of ATP. Blue light causes stomatal opening in the presence of CO by stimulating ATP synthesis.

Immunodeficiency in ESRD-patients is linked to altered IL-2 receptor density on T cell subsets.

The interdependence of blunted T cell proliferation induced by anti-CD3 monoclonal antibodies (mAb) and the preactivation of T lymphocytes (CD25+) in ESRD patients was investigated in this study. We focused on the density of IL-2 (CD25) receptors [IL-2R] on the lymphocyte surface rather than enumeration of IL-2R positive cells. The effect of exogenous IL-2 on these parameters was also tested. Blunted T lymphocyte proliferation induced by anti-CD3 mAb is only partially corrected by addition of exogenous IL-2 after 24 hrs. Freshly isolated uremic CD4 T cells show higher percentage of IL-2 positive cells and a higher IL-2R density on the cell surface compared to controls. However, after anti-CD3 mAb stimulation the number of IL-2R positive cells and IL-2R density in CD4 T subset was significantly lower than in samples from normal donors. Exogenous IL-2 had no influence on IL-2R expression on CD4 cells in uremic patients. On the other hand, following anti-CD3 mAb stimulation uremic CD8 cells reveal more IL-2R positive cells with higher IL-2R density than in controls. Moreover, exogenous IL-2 enhance IL-2R expression and density on uremic CD8 cells more than in controls. Our results suggest that the blunted T cell proliferation in ESRD patients might result from (a) preactivation of CD4 T cells, (b) diminished response of uremic CD4 T cells to IL-2, and (c) higher suppressor cells activity.

Malignancies of the genito-urinary system following renal transplantation.

OBJECTIVE: To analyse the development of malignancies of the genito-urinary system after renal transplantation. PATIENTS AND METHODS: A total of 868 renal graft recipients were followed up over a mean period of 41.8 +/- 45 months. Fifteen patients received grafts from living related donors and 853 were transplanted with kidneys from cadavers. RESULTS: Twelve patients (1.4%) exhibited cancer of the genito-urinary system: 11 tumours were de novo malignancies. One small renal carcinoma was transplanted from a living related donor. The incidence of tumours of the genito-urinary system was 34 in 100,000 patient years in the patients treated with cyclosporin and 32 in 100,000 patient years in the conventional therapy group. Four patients died within a mean survival time of 14.4 months. Comparison of our results with sex- and age-specific incidence rates in a reference population showed an increase in malignant tumours of the genitourinary system by a factor of 7.3 in males and 11.2 in females. CONCLUSIONS: The frequency of disorders after transplantation necessitates routine examinations in organ transplanted recipients both before and at regular intervals after transplantation, including the patient's native kidneys and cervical smears in females.

Tumors after renal transplantation.

The purpose of this retrospective study was to analyze the development of malignancies after renal transplantation. 633 renal graft recipients with an organ function longer than 1 year were followed up over a mean period of 67.6 +/- 48.7 months. Only 12 recipients received grafts from living-related donors. 38 recipients (6.0%) exhibited cancer of either the skin, the genitourinary system, the bronchial system, the female breast, or the colon. All tumors were de novo malignancies. The number of patients developing a tumor was significantly higher in the cyclosporine-treated group than in patients with conventional immunosuppression. 15 patients died within a mean survival time of 7.7 +/- 12.1 months. The frequency of disorders makes it necessary for organ transplant recipients to have routine examinations both before and at regular intervals after transplantation. This includes examination of the patient's skin, native kidneys and cervical smears for females.

The risk of infection following OKT3 and antilymphocyte globulin treatment for renal transplant rejection: results of a single center prospectively randomized trial.

Some 43 of 60 (72%) renal allograft recipients who were prospectively randomized to receive either OKT3 monoclonal antibody (n = 30) or ALG (antilymphocyte globulin) polyclonal antibody (n = 30) for steroid-resistant rejection suffered from infection, 25 (83%) following OKT3 and 18 (60%) following ALG treatment (P < 0.05). Clinically evident herpes infection was most frequently seen (9 and 7, respectively), followed by pneumonia (6 and 1, respectively P < 0.05), urinary tract infection and wound infection (2 of each in both groups) fungal (Candida) and multibacterial infections. One patient died in each group due to cytomegalovirus (CMV) pneumonia, giving a mortality of 4.3% in each group. Actuarial 1-year graft and patient survival rates were 80% and 97% in both groups, respectively. It is concluded that ALG and OKT3 are equally effective in renal allograft rejection resistant to steroid treatment, however, the risk of infection appears to be higher with OKT3.

[Disordered alpha 2-adrenoreceptor function in hemodialysis patients with renal anemia--a possible cause of increased blood pressure in relation to recombinant human erythropoietin?]. / Gestörte alpha 2-Adrenozeptorfunktion bei Hämodialysepatienten mit renaler Anämie--eine mögliche Ursache der Blutdrucksteigerung unter rekombinantem humanem Erythropoietin?

Nine patients on maintenance hemodialysis and transfusion-demanding renal anemia (group A) were treated with rHuEPO 120 IU/kg i.v. three times per week. Hemoglobin-content was raised from 7.2 +/- 0.9 to 10.4 +/- 0.8 g/dl. In all patients blood pressure rose, three patients developed arterial hypertension. Mean diastoloic blood pressure was 66 +/- 12 and 78 +/- 16 mmHg (p less than 0.001) before and after rHuEPO. Rise in blood pressure was accompanied by a significant fall in plasma-noradrenaline-levels (from 498 +/- 100 to 383 +/- 75 pg/ml; p less than 0.05) and alpha 2-adrenoceptor-density (from 574 +/- 76 to 384 +/- 49; p less than 0.05). Compared to nine patients on maintenance hemodialysis and hematocrit over 30% (group B), patients with severe renal anemia (group A before treatment) had higher densities of alpha 2-adrenoceptors (574 +/- 76 vs. 218 +/- 32; p less than 0.001) despite higher plasma-noradrenaline-levels (498 +/- 100 vs. 399 +/- 63; n.s.). We suppose a anemia-related disturbance of alpha 2-receptor-function with the result of abolished receptor down-regulation and impaired vascular reagibility to vasoconstricting stimuli. With the correction of anemia receptor-function improves, receptor down-regulation as well as vascular reagibility is re-established resulting in augmented vascular resistance and higher blood pressure.

Does uremic environment down-regulate T cell activation via TCR/CD3 antigen receptor complex?

TCR/CD3 receptor complex plays a central role in antigen recognition and T cell activation. Therefore, the present study investigates TCR alpha/beta (TCR-1) and CD3 receptor density (RD, number of receptors per cell) on uremic CD4 T lymphocytes in relation to T cell proliferative response induced by anti-CD3 monoclonal antibodies (mAb). The influence of uremic serum on TCR/CD3 receptor expression of normal and uremic CD4 T lymphocytes was evaluated as well. We found, that: a) percentage of TCR-1 and CD3 positive cells of freshly isolated CD4 T lymphocytes is the same in controls and ESRD-patients, but the TCR/CD3 RD is lower on uremic CD4 T lymphocytes, b) Incubation for 24 h with uremic serum lowers TCR/CD3 RD on normal and uremic CD4 T cells, c) There is positive correlation between TCR/CD3 RD and anti-CD3 induced lymphocyte proliferation. These data might also support the hypothesis that blunted T-cell response to antigen in uremia is due to down-regulation of the TCR/CD3 receptor complex by uremic milieu.

Signalling via the TCR/CD3 antigen receptor complex in uremia is limited by the receptors number.

The TCR/CD3 receptor complex plays a key role in antigen recognition and T-cell activation. Therefore, the present study investigates TCR alpha/beta (TCR1) and CD3 receptor density (RD, number of receptors per cell) on uremic helper-inducer (CD4) T lymphocytes in relation to T-cell proliferative response induced by anti-CD3 monoclonal antibodies (mAb). We found, that: (1) the number of TCR/CD3 receptors on uremic helper-inducer (CD4) T lymphocytes is decreased and correlated well with the blunted lymphocyte proliferation induced by anti-CD3 mAb; (2) these findings were associated with diminished binding capacity of IL-1 beta and IL-6 to their receptors (IL-1R, IL-6R) on helper-inducer T cells, whereas (3) the IL-2 receptor (IL-2R) and molecule expression of CD4 and lymphocyte function antigen-1 (LFA-1) were increased, and (4) uremic monocytes displayed a decreased density of intercellular adhesion molecule-1 (ICAM-1) expression, which interacts as receptor-ligand pair with LFA-1. The incubation of uremic and control peripheral blood mononuclear cells with uremic serum enhanced these above-mentioned changes in the expression of examined receptors and molecules. These data might also support the hypothesis that the blunted T-cell response to antigen in uremia is due to downregulation of the TCR/CD3 receptor complex by uremic milieu.