TENTH ANNUAL CLINICAL NEPHROLOGYMEETING ABSTRACTS
57 SEVELAMER HCL IMPROVES PARATHYROID HORMONE (PTH) AND BONE FUNCTION 1N PERITONEAL DIALYSIS (PD) PATIENTS WITH PROBABLE LOW TURNOVER BONE DISEASE Sharon Mae*, Jan Paterson, Cindy Murphy, Erika Johnson, Mark Deeg. Indiana Univ and Roudebush VAMC, Indpls, IN Patients on PD are more likely to have adynamic or low-turnover bone disease and hypereholesternlemia than are HD patients. Calcium containing phosphate binders may contribute to the high incidence of adynamic bone disease due to the positive calcium balance they induce. We hypothesized that sevelamer HCL (Renagel®, Geltex/Genzyme, ½c = SEV) may normalize the excessively low PTH levels observed in PD patients because of the decreased calcium load compared to calcium acetate. To test this, we compared these phosphate binders in PD patients who had a persistent PTH < 200 pg/ml, and BAP < 20 IU, on no Vitamin D in a randomized, cross-over design with 12 wk treatment arms. In each man, PTH, BAP, total calcium corrected for albumin (tCa) and ionized calcium (iCa) were measured after a 2 wk washout (=baseline) and every 4 wks for each 12 wk treatment ann. In addition, the subjects had pre and post lipid studies. Five patients completed the study, with one shortened sevelamer (SEV) arm due to diarrhea. Three other patients dropped out due to transpiantatinn and pancreatitis. The PTH decreased from baseline to 12 weeks by 21 ~- 16 % in the CaA, vs an increase of 47 :k 12 % in the SEV arm (Mean ± SEM, p = 0.05). This occurred despite equivalent tCa (+0.02 ± 0.11 CaA vs +0.15 ± 0.06 mg/dl in SEV), iCa (-0.31 ± 0.19 CaA vs -0.95 :k 0.17 mg/di in SEV), and phosphorus (-0.31 ± 0.19 CaA vs -0.95 ± 0. I7 rag/all in SEV; all p = NS). The BAP decreased in the CaA arm by 1.52 ± 1.06 IV, compared to an increase of 2.20 ± 0.72 IU in the SEV arm (p < 0.007), supporting improved osteuhlast function. The to~al cholesterol was unchanged in the CaA group (9.5 :~ 13.5%) but decreased by 26.9 ~=22.9% in the SEV arm, p = 0.08, due primarily to changes in LDL. Dietary recall revealed similar calcium, phosphorus, and cholesterol intake in each arm for each patient. In summary, SEV appears to be a safe and effective phosphate binder in PD patients. The rise in PTH and BAP, and decrease in cholesterol indicates sevelamer may offer a distinct advantage over CaA. Larger, long-term studies are required to confirm these f'mdings.
58 SUCCESSFUL TREATMENT OF STEROIDRESISTANT MINIMAL CHANGE DISEASE WITH MYCOPHENOLATE MOFETIL, Andrfis Mogyor6si, H. Robert Lippman, George M. Feldman. VCU/Medical College of Virginia and McGuire VAMC, Richmond, Virginia. Clinical experience with mycophenolate mofetil (MMF) in minimal change disease (MCD) suggests that it may be effective in steroid-resposive cases. We report a case of steroid- and cyclosporin-resistant MCD with severe nephrotic syndrome that responded to MMF with complete remission. A 45,year old male patient with nephrotic syndrome (proteinuria of 15 g/day) and MCD was started on lisinopril and high-dose prednisone. After 5 months of high dose peroral steroids his proteinuria was essentially unchanged. Cyclosporin A was added, and his proteinuria fell temporarily (to 2.99 g/day) but a month later he relapsed and eyclosporin A was discontinued. The patient refused cyclophosphamide; MMF was started at a doge of I g twice daily. Prednisone was tapered offbecanse of ongoing severe aane. Three months into the treatment with MMF his MCD went into remission with a proteinuria of 0.6 g/day. Five months after the initiation of therapy with MMF he demonstrated a complete remission (proteinuria of 0i13 g/day and normal renal function). MMF was then slowly tapered and finally discontinued. Four months after dis~ontinnation of MMF he remains in complete remission. Although a spontaneous remission can't be ruled out, the fight temporal relationship of the initiation of MMF with the impressive improvemem militates for a causal relationship. This case underlines the need for a prospective controlled trial evaluating the efficacy of MMF in steroid:resistant MCD.
59 USE OF THE LIFESITE® HEMODIALYSIS ACCESS SYSTEM REDUCES RISK OF VASCULAR ACCESS INFECTIONS. Moron= Tewksbury, MA Preventing vascular access related infections remains a significant challenge in the management of hemodialysis patients. A new subcutaneous device (LifeSite® Hemodialysis Access System, Vasca, Inc. Tewksbury, MA) was designed to reduce these complications and is now available for use in hemodialysis patients. The infection rate and hospitalization associated with the use of the LifeSite System (n=34) was compared to a Tesio-Cath (n=34)hemodialysis catheter (Medcomp®, Harleysville, PA) in a prospective multicenter study. During the first 6 months of the study the overalI infection rate in the LifeSite group was significantly lower than observed in the Tesin-Cath group (2.0 versus 5.6 infections per 1,000 patiant-days; p=0.022). The device-related infection rate was also sign/ficantly lowet for the LifeSite group (t.3 versus 3.3 per 1,000 patient-days; p--0.040) compared to the Tesio-Cath group. LifeSite patients were hospitalized for a total of 11 days as a result of device-related infections as compared to 75 days for the Tesio-Cath (o=0.011). Infections in the LifeSite group were less likely to require additional drug therapy than infections experiences by Tesin-Cath patients. Infection resulted in device removal for 5 patients in the Tesio-Cath group. No LifeSite patients required device removal for infections during the 6 month observation period. The reduced incidence of infection observed in the LifeSite patients is likely due to the subcutaneous placement of the device and the unique design of the LifeSite valves which allow the instillation of a 70% isopropyl alcohol (IPA) solution prior to and after the hemodiedysis session. The latter provides for the ability to cleanse the valve, valve pocket, and buttonhole tract. Daily irrigation of the LifeSire valves with IPA in conjunction with IV antibiotics allows clinicians the possibility to treat through device related infections in patients. If this approach is unsuccessful, the LifeSite carmutas can be exchanged in a simple procedure and may prevent the need for explanting the device.
6O THE THI/TH2 PARADIGM REVISITED. REGULATORY FUNCTIONS OF ALLOREACTIVE TH2 CLONES tN VIVO. hi. Naiafian: M.PL Sayegh, A.M, Waag& Renal Division, Brigham and Women's Hospital, Boston, MA We enmpared the function ofT tell clones generated from grafts of rejecting versus tol~ant animals in vivo. T cell lines were gen~ated from kidneys of LEW animals transplanted with WF kidneys and either telt without lreatment (taken at day 7) or treated with 0.5 nag ofCTLA4tg i.v, on day 2 (taken at day 150) post-transplant. Both T cell lines were generated against a donor-derived (WF) class II MHC peptide ~Tl.Dub20-44) presented by self antigen-presenting ceils via indirect alloreeognitien, From these lines individual T celt clones were derived by limiting dilution. The rejecting ea}l line and cAones produced INF-g but not IL---4 and 1L- l0 in culture, while the T celt line and clones from the tolerant animals produced IL-4 and ~A~-I0 but not/NF-g aibm"stimulation with the RTI,D20-4;4 aliopepfide in vitro. We then injected the Thl versus Th2 clones expressing the same TCR Vb 9 into naive LEW rats. Five days inter the animals were challenged in the ear with the RTI.D20-44 peptide for measurement of DTH responses Mter 48 hours. A significant (p<0.0001) DTH response was observed fotlowmg cha/lenge wit~ RT1.D20-44 peptide by the Thl clones injected animals (delta ear thickness~l,3_-~0.2, n=7) as compured with. the Th2 clones injected animals (de]ha ear thickness=d).4±0.2, n=7). tn order to study the' putative regulatory functions of Th2 clones in v/vo, naive LEW animals (n--4) were injected with a mixlure ofequat nmnbers of Tht and irradiated Th2 clones as above. Animals were then challenged with RT1,D20-44 peptide in one ear and donor WF sptenoeytes in the other ear. DTH responses to both the allopeptide (delta e a r thickness=0.2_+0.1) and donor cells (delta ear thickness=0) Were significantly (p