Optimally tolerated dose of lapatinib in combination with docetaxel plus trastuzumab in first-line treatment of HER2-positive metastatic breast cancer.

BACKGROUND: This phase IB, open-label, dose-escalation study evaluated the safety, tolerability, and optimally tolerated regimen (OTR) of lapatinib in combination with docetaxel and trastuzumab in patients with previously untreated stage IV metastatic breast cancer (MBC) tumors overexpressing human epidermal growth factor receptor 2 (HER2). PATIENTS AND METHODS: Evaluated dose regimens included lapatinib (500-1500 mg/day), docetaxel (triweekly; 60-100 mg/m²), and trastuzumab (weekly; 2 mg/kg fixed dose); prophylactic granulocyte colony-stimulating factor was included with regimens with ≥750 mg/day lapatinib. End points included OTR and safety/tolerability (primary), overall response rate (ORR), and pharmacokinetics (secondary). RESULTS: None of the patients (N = 53) experienced dose-limiting toxic effects (DLTs) at the highest dose level; thus, the OTR of lapatinib with 100 mg/m(2) docetaxel was not determined. Common adverse events included diarrhea, nausea, alopecia, fatigue, and rash; grade 3/4 (≥2 patients) were neutropenia, diarrhea, leukopenia, peripheral neuropathy, and rash. Seven patients had DLTs (cycle 1). In 45 patients with measurable disease confirmed by bone scan, investigator-assessed ORR was 31%; without bone scan, confirmation was 64%; 8 patients without measurable disease were evaluated as stable. Lapatinib/docetaxel plasma concentrations were positively associated with complete response. CONCLUSIONS: Lapatinib/docetaxel/trastuzumab is a feasible and well-tolerated treatment of untreated HER2-positive stage IV MBC. Two lapatinib/docetaxel OTR doses were recommended (1250 mg/75 mg/m²; 1000 mg/100 mg/m²). CLINICAL TRIAL NUMBER: NCT00251433.

Imaging near metal with a MAVRIC-SEMAC hybrid.

The recently developed multi-acquisition with variable resonance image combination (MAVRIC) and slice-encoding metal artifact correction (SEMAC) techniques can significantly reduce image artifacts commonly encountered near embedded metal hardware. These artifact reductions are enabled by applying alternative spectral and spatial-encoding schemes to conventional spin-echo imaging techniques. Here, the MAVRIC and SEMAC concepts are connected and discussed. The development of a hybrid technique that utilizes strengths of both methods is then introduced. The presented technique is shown capable of producing minimal artifact, high-resolution images near total joint replacements in a clinical setting.

Magnetic resonance imaging near metal implants.

The desire to apply magnetic resonance imaging (MRI) techniques in the vicinity of embedded metallic hardware is increasing. The soft-tissue contrast available with MR techniques is advantageous in diagnosing complications near an increasing variety of MR-safe metallic hardware. Near such hardware, the spatial encoding mechanisms utilized in conventional MRI methods are often severely compromised. Mitigating these encoding difficulties has been the focus of numerous research investigations over the past two decades. Such approaches include view-angle tilting, short echo-time projection reconstruction acquisitions, single-point imaging, prepolarized MRI, and postprocessing image correction. Various technical advances have also enabled the recent development of two alternative approaches that have shown promising clinical potential. Here, the physical principals and proposed solutions to the problem of MRI near embedded metal are discussed.

Analysis of dermatologic events in patients with cancer treated with lapatinib.

PURPOSE: Dermatologic events (DEs) in patients with cancer treated with lapatinib, a small-molecule dual tyrosine kinase inhibitor (TKI) of epidermal growth factor receptor (EGFR [ErbB1]) and HER2 (ErbB2), were characterized. PATIENTS AND METHODS: Nine clinical trials of metastatic cancer were included in this analysis. Lapatinib was administered at doses ranging from 1000 to 1500 mg/day as monotherapy (n=928) or in combination with paclitaxel or capecitabine (n=491). Patients not treated with lapatinib comprised the control group. Dermatologic events included hand-foot syndrome, rash, hair disorder, dry skin, pruritus/urticaria, skin disorder, skin infection, and nail disorder; DEs were characterized based on type, time to onset, severity, duration, and required interventions. RESULTS: Fifty-eight percent of patients treated with lapatinib monotherapy, 74% treated with lapatinib plus paclitaxel or capecitabine, and 53% in the control group developed DEs. Among patients receiving lapatinib monotherapy, 55% experienced grade 1/2 DEs, 3% had grade 3 DEs, and no grade 4 DEs were observed. The most common DE was rash (43%); all other events occurred in

Quantitative Susceptibility Mapping after Sports-Related Concussion.

BACKGROUND AND PURPOSE: Quantitative susceptibility mapping using MR imaging can assess changes in brain tissue structure and composition. This report presents preliminary results demonstrating changes in tissue magnetic susceptibility after sports-related concussion. MATERIALS AND METHODS: Longitudinal quantitative susceptibility mapping metrics were produced from imaging data acquired from cohorts of concussed and control football athletes. One hundred thirty-six quantitative susceptibility mapping datasets were analyzed across 3 separate visits (24 hours after injury, 8 days postinjury, and 6 months postinjury). Longitudinal quantitative susceptibility mapping group analyses were performed on stability-thresholded brain tissue compartments and selected subregions. Clinical concussion metrics were also measured longitudinally in both cohorts and compared with the measured quantitative susceptibility mapping. RESULTS: Statistically significant increases in white matter susceptibility were identified in the concussed athlete group during the acute (24 hour) and subacute (day 8) period. These effects were most prominent at the 8-day visit but recovered and showed no significant difference from controls at the 6-month visit. The subcortical gray matter showed no statistically significant group differences. Observed susceptibility changes after concussion appeared to outlast self-reported clinical recovery metrics at a group level. At an individual subject level, susceptibility increases within the white matter showed statistically significant correlations with return-to-play durations. CONCLUSIONS: The results of this preliminary investigation suggest that sports-related concussion can induce physiologic changes to brain tissue that can be detected using MR imaging-based magnetic susceptibility estimates. In group analyses, the observed tissue changes appear to persist beyond those detected on clinical outcome assessments and were associated with return-to-play duration after sports-related concussion.

Effect of acute hypertension on sodium reabsorption by the proximal tubule.

The effect of acute hypertension on sodium reabsorption by the proximal tubule was studied in rats by means of micropuncture methods. Hypertension was induced by bilateral carotid artery ligation and cervical vagotomy. Within a few minutes after blood pressure rose (30-60 mm Hg above control levels), a moderate natriuresis and diuresis began. Proximal sodium reabsorption, measured by two independent methods, was found to be markedly suppressed, both in absolute amount per unit length and per unit of tubular volume (C/pir(2)). The ratio between tubular volume and glomerular filtration rate (GFR) (pir(2)d/V(0)) was found to be increased. These observations indicate that the inhibition of proximal sodium reabsorption induced by hypertension cannot be explained by the tubular geometry hypothesis of sodium regulation. Several possible hormonal mechanisms were investigated. Intravenous d-aldosterone did not prevent the suppression of sodium transport due to acute hypertension, nor did chronic oral saline loading to reduce the renal content of renin. Constriction of the suprarenal aorta, with maintenance of a normal renal perfusion pressure, did prevent the inhibition of proximal transport during carotid artery occlusion, thus excluding an extrarenally produced natriuretic hormone as the mechanism. The observations are compatible with the view that sodium transport was inhibited either by an intrarenal natriuretic hormone or by an increase in the interstitial volume of the kidney produced by a transient hydrostatic pressure gradient across the peritubular capillaries. The latter seems more likely to us because of the rapidity of onset of the natriuresis, and because removing the renal capsule and releasing the surface interstitial fluid prevented the effect of hypertension on proximal sodium transport.

Effect of changes in renal perfusion pressure on the suppression of proximal tubular sodium reabsorption due to saline loading.

Rapid intravenous infusion of saline is known to suppress reabsorption of sodium and water in the proximal tubule. It has previously been shown that this suppression is accompanied by two changes which in combination might account for the over-all decrease in reabsorption: a reduction in the intrinsic reabsorptive capacity of the tubular epithelium (C/pir(2)) and a reduction in the ratio between tubular volume and GFR (pir(2)d/V(o)). The present micropuncture experiments were carried out in order to study the possible role of altered peritubular physical forces (hydrostatic and colloid oncotic pressure) in mediating these two changes. Proximal tubular reabsorptive capacity, transit time, fractional reabsorption of sodium and water, pir(2)d/V(o), and intratubular hydrostatic pressure were measured in saline-loaded rats during acute changes in renal perfusion pressure induced by intermittent constriction of the abdominal aorta. We found that when renal perfusion pressure was lowered to 70-90 mm Hg, the usual effects of saline loading on C/pir(2), pir(2)d/V(o), and fractional reabsorption in the proximal tubule were greatly minimized. When the aortic clamp was released and renal perfusion pressure allowed to rise, C/pir(2), pir(2)d/V(o), and fractional reabsorption fell markedly to levels characteristically seen in saline diuresis. Reclamping of the aorta reversed all of these changes. In order to determine whether the changes in C/pir(2) accompanying changes in renal perfusion pressure were mediated by a circulating natriuretic hormone, we assayed in hydopenic rats the dialysate of plasma collected from saline-loaded rats during and after release of aortic constriction by the split oil drop method. No significant difference in reabsorptive half-time (t(1/2)) was found between the two dialysates, and t(1/2) with both dialysates was approximately the same as was found when isotonic saline was injected in the tubules of hydropenic control animals. These observations suggest that the large changes in C/pir(2) which occurred with changes in renal perfusion pressure in saline-loaded rats were not mediated by a circulating hormone. We suggest that the reduction in C/pir(2), pir(2)d/V(o), and fractional reabsorption which occurs in the proximal tubule during a saline diuresis is related to the rise in hydrostatic pressure within the kidney.

Basic fibroblast growth factor augments podocyte injury and induces glomerulosclerosis in rats with experimental membranous nephropathy.

Podocyte injury is believed to contribute to glomerulosclerosis in membranous nephropathy. To identify the factors involved, we investigated the effects of basic fibroblast growth factor (bFGF), a cytokine produced by podocytes, on rats with membranous nephropathy (passive Heymann nephritis [PHN]). All rats received a daily i.v. bolus of 10 microg bFGF or vehicle from days 3-8 after PHN induction. In proteinuric PHN rats on day 8, bFGF injections further increased proteinuria. Podocytes of bFGF-injected PHN rats showed dramatic increases in mitoses, pseudocyst formation, foot process retraction, focal detachment from the glomerular basement membrane, and desmin expression. bFGF injections in PHN rats did not alter antibody or complement deposition or glomerular leukocyte influx. bFGF-injected PHN rats developed increased glomerulosclerosis when compared with control PHN rats. Also, bFGF induced proteinuria and podocyte damage in rats injected with 10% of the regular PHN-serum dose. None of these changes occurred in bFGF-injected normal rats, complement-depleted PHN rats or rats injected with 5% of the regular PHN serum dose. These divergent bFGF effects were explained in part by upregulated glomerular bFGF receptor expression, induced by PHN serum. Thus, bFGF can augment podocyte damage, resulting in increased glomerular protein permeability and accelerated glomerulosclerosis. This bFGF action is confined to previously injured podocytes. Release of bFGF from glomerular sources (including podocytes themselves) during injury may represent an important mechanism by which podocyte damage is enhanced or becomes self sustained.

A phase I and pharmacokinetic study of lapatinib in combination with infusional 5-fluorouracil, leucovorin and irinotecan.

BACKGROUND: This study determined the optimally tolerated regimen (OTR) of oral lapatinib administered in combination with infusional 5-fluorouracil (5-FU), leucovorin and irinotecan (FOLFIRI) and assessed the safety, tolerability and pharmacokinetics of the combination. PATIENTS AND METHODS: Twenty-five patients were enrolled; 12 patients were treated at three dose levels to determine OTR; then 13 patients were treated at OTR to evaluate the pharmacokinetics of the combination. RESULTS: The 2-weekly OTR comprised lapatinib 1250 mg/day with irinotecan 108 mg/m(2) (day 1) and leucovorin 200 mg/m(2), 5-FU bolus 240 mg/m(2) and 5-FU infusion 360 mg/m(2) (days 1 and 2); doses of 5-FU and irinotecan represent a 40% reduction in dose compared to conventional FOLFIRI. Dose-limiting toxicities were grade 3 diarrhoea and grade 4 neutropenia. Co-administration of lapatinib increased the area under the plasma concentration-time curve of SN-38, the active metabolite of irinotecan, by an average of 41%; no other pharmacokinetic interactions were observed. Of 19 patients evaluable for disease response assessment, four patients had partial response and nine patients had stable disease. CONCLUSION: The combination of lapatinib and FOLFIRI is safe and demonstrates clinical activity; the documented PK interaction can effectively be compensated by lowering the doses of 5-FU and irinotecan. This regime may be further tested in a phase II trial.

Life-threatening complications of extracorporeal treatment in patients with severe eosinophilia.

We report three patients with massive eosinophilia of different etiology who developed bronchoconstriction, hypotension, and shock shortly after dialysis or leukapheresis had been begun. In two cases, ethylene oxide-free materials had been used ruling out an allergic reaction related to this compound. Degranulation of eosinophils with release of eosinophil peroxidase may have caused the observed adverse reactions, as suggested by in vitro experiments with blood from the three patients. Our observations draw attention to the fact that extracorporeal therapies may initiate life-threatening complications in patients with severe eosinophilia.

Serum erythropoietin measurements using the fetal mouse liver cell culture: the importance of reduction of variation in the specific activity of radioiron--transferrin.

Because of varying iron--transferrin concentrations in different serum samples, and varying test serum portions within the culture, variations of the radioiron--transferrin/total iron--transferrin ratio are inevitable, when serum erythropoietin (Ep) concentrations are measured using the fetal mouse liver cell assay. It could be demonstrated that radioiron uptake is directly proportional to the specific activity of radioiron--transferrin, when the latter varies over the range which is inherent to the method. Variations of the ratio of radioiron--transferrin/total iron--transferrin were reduced by preincubating radioiron with human transferrin, and by minimizing the test serum portion of the culture. With this modified in vitro bioassay, serum Ep concentrations of 59 healthy subjects were measured. Mean serum Ep concentration was 136 +/- 66 (s.d.) mU/ml.

Effect of ranitidine on the pharmacokinetics of triazolam and alpha-hydroxytriazolam in both young (19-60 years) and older (61-78 years) people.

OBJECTIVE: This study evaluated the effect of oral ranitidine (75 mg and 150 mg) on the pharmacokinetics of triazolam (0.25 mg) and its major metabolite, alpha-hydroxytriazolam, in both young and older people. Metabolite data were used to distinguish the mechanism of this interaction. METHOD: This was a randomized, open-label, 3-way crossover study. Eighteen young (19-60 years) and 12 older (61-78 years) men and women were randomly assigned to receive evening doses of triazolam 0.25 mg (1) alone, (2) on the third day of dosing ranitidine 75 mg twice daily for 4 days, and (3) on the third day of dosing ranitidine 150 mg twice daily for 4 days. RESULTS: In the young group, mean triazolam area under the concentration-time curve from time zero to infinity [AUC(0-infinity)] was 10% and 28% higher after treatment with 75 mg and 150 mg ranitidine, respectively. In the older group, mean triazolam AUC(0-infinity) was 31% and 28% higher after treatment with 75 mg and 150 mg ranitidine, respectively. There was no change in the alpha-hydroxytriazolam/triazolam AUC(0-infinity) ratio in either age group, indicating that neither formation nor elimination of alpha-hydroxytriazolam was affected by ranitidine. There were no changes in the half-life of triazolam or alpha-hydroxytriazolam. CONCLUSION: Ranitidine increases oral absorption of triazolam in both young and older people. This effect is likely caused by elevation of gastrointestinal pH, allowing for greater absorption of acid-labile triazolam. The difference in this effect between age groups at the lower 75-mg dose of ranitidine suggests that older people may be more sensitive to the antisecretory effect of ranitidine.

Elevated vascular angiotensin converting enzyme mediates increased neointima formation after balloon injury in spontaneously hypertensive rats.

OBJECTIVE: To measure the effect of hypertension on neointima formation after balloon injury of rat aorta and its association with the local angiotensin converting enzyme (ACE) concentration. Balloon angioplasty of the thoracic aorta using a 2 French Fogarty catheter was performed in spontaneously hypertensive rats (SHR) and normotensive Sprague-Dawley (SD) rats. RESULTS: The injured aortic wall of SHR had already significantly higher ACE concentrations than did the uninjured aortic wall of normotensive SD rats (media: 729 +/- 37 dpm/mm2 in SHR versus 496 +/- 38 dpm/mm2 in SD rats, P < 0.01; intima: 83 +/- 5 dpm/mm2 versus 68 +/- 6 dpm/mm2 in SD rats, P < 0.01). Fourteen days after injury of the aorta the hypertensive rats had significantly higher neointima: media ratios than did the normotensive rats (0.83 +/- 0.09 versus 068 +/- 0.01, P < 0.01). This was associated with a significant increase in vascular media and neointima ACE concentrations in SHR (media 965 +/- 25 dpm/mm2, neointima 614 +/- 48 dpm/mm2) compared with those in normotensive SD rats after balloon angioplasty (media 669 +/- 23 dpm/mm2, neointima 287 +/- 33 dpm/mm2, P < 0.01). ACE inhibitor treatment with 10 mg/kg body weight lisinopril daily for 14 days by gavage reduced neointima proliferation in hypertensive and normotensive rats (neointima: media ratio: 0.35 +/- 0.02 for SHR, P < 0.01, versus untreated SHR with balloon injury; 0.28 +/- 0.01 for SD, P < 0.01, versus untreated SD rats with balloon injury). This was associated with significant vascular media ACE inhibition (SHR 149 +/- 9 dpm/mm2; SD rats 118 +/- 7 dpm/mm2; P < 0.01 versus untreated controls with balloon injury) and neointima ACE inhibition (SHR 73 +/- 4 dpm/mm2, SD rats 63 +/- 7 dpm/mm2, P < 0.01, versus untreated controls with balloon injury), but also lowered the blood pressure in SHR significantly (to 148 +/- 5 mmHg, P < 0.01, versus untreated SHR with balloon injury). When this drop in blood pressure was prevented by feeding the rats a high-salt diet (SHR with ACE inhibitor plus high salt-diet group blood pressure 193 +/- 3 mmHg, P = 0.57, versus untreated SHR) hypertension per se without the local ACE increase (ACE concentration in SHR with ACE inhibitor high-salt diet rats' media 167 +/- 10 dpm/mm2 and neointima 81 +/- 9 dpm/mm2) had only a mild effect on neointima formation after balloon angioplasty (neointima: media ratio 0.4 +/- 0.01 for SHR with ACE inhibitor plus high-salt diet versus 0.35 +/- 0.02 for SHR with ACE inhibitor plus normal-salt diet P < 0.05). Treatment with 10 mg/kg body weight angiotensin II subtype 1 receptor antagonist losartan potassium daily for 14 days by gavage was associated with a reduction in neointima formation similar to that observed with the ACE inhibitor both for SHR and for SD rats (neointima: media ratio 0.32 +/- 0.04 for SHR with losartan, 0.27 +/- 0.03 for SD rats with losartan; P < 0.01, versus untreated controls with balloon injury) suggesting that ACE inhibitor prevented neointima formation, at least in part by, reducing the local production of angiotensin II. CONCLUSION: Neointima formation after balloon angioplasty in SHR is increased compared with that in normotensive SD rats. This is due mainly to there being a higher degree of activation of the renin-angiotensin system in the aorta of the SHR before and after balloon injury compared with that in normotensive SD rats measured in terms of the increased vascular ACE concentrations. Blood pressure alone had only a moderate effect on neointima formation.

Plasma levels of tumor necrosis factor (TNF) and soluble TNF receptors in kidney transplant recipients.

Tumor necrosis factor-alpha is elevated in plasma during kidney transplant rejection. However, the measurement and biological activity of TNF alpha is influenced by inhibitory soluble TNF receptors. We therefore determined plasma levels of TNF alpha and the 2 soluble TNF receptors, the 55-kDa TNF receptor (TNF-sR55) and the 75-kDa TNF receptor (TNF-sR75), by immunoassays in 25 patients before and daily after kidney transplantation. Plasma samples were retrospectively assigned to 3 groups: (1) patients with well-functioning grafts (n = 14); (2) patients with biopsy-proven graft rejections (n = 7 patients with 10 rejections); and (3) patients with episodes of CsA nephrotoxicity (n = 4 patients with 9 samples). On the day of biopsy-proven graft rejection, TNF alpha increased from 8.6 +/- 0.9 pg/ml to 14.8 +/- 3.5 pg/ml (P < 0.02), TNF-sR55 from 6.6 +/- 1.3 ng/ml to 9.0 +/- 1.2 ng/ml (NS), and TNF-sR75 from 10.3 +/- 1.0 ng/ml to 15.3 +/- 2.0 ng/ml (P < 0.01). During episodes of CsA toxicity, TNF alpha levels did not change, TNF-sR55 increased from 5.2 +/- 0.5 ng/ml to 10.5 +/- 0.5 ng/ml (P < 0.01), and TNF-sR75 increased from 10.2 +/- 0.8 ng/ml to 17.5 +/- 0.9 ng/ml (P < 0.01). There was a strong correlation between serum creatinine and plasma TNF-sR55 (r = 0.7, P < 0.001) and TNF-sR75 (r = 0.7, P < 0.001), but not with TNF alpha. Therefore, levels of TNF-sR55 and TNF-sR75 were corrected for serum creatinine. An index expressing TNF alpha over actively released soluble receptors (index = TNF alpha/(corr.TNF-sR55 + corr.TNF-sR75)) detected rejection episodes with a sensitivity of 70-80% and a specificity of 89%. We conclude that the measurement of plasma TNF alpha in combination with its soluble receptors is superior to isolated TNF alpha determinations in discriminating acute graft rejection from episodes of CsA toxicity in kidney transplant recipients.

Renal transplantation for patients with autoimmune diseases: single-center experience with 42 patients.

BACKGROUND: In patients with autoimmune diseases such as vasculitis or systemic lupus erythematosus (SLE), end-stage renal disease develops in a high percentage of patients, and kidney transplantation has become a therapeutic option. However, only limited data about the prognosis and outcome after kidney transplantation are available. METHODS: Long-term graft survival and graft function of renal transplant recipients with SLE, Wegener's granulomatosis, microscopic polyangiitis, Goodpasture's syndrome, and Henoch-Schonlein purpura were evaluated in a single center. In addition, the incidence of renal and extrarenal relapses and the impact of the immunosuppressive therapy on the course of the autoimmune disease were studied. RESULTS: Renal transplant recipients with autoimmune diseases such as vasculitis and SLE had a patient survival rate (94% after 5 years) and a graft survival rate (65% after 5 years) comparable to those of patients with other causes of end-stage renal disease (patient survival 88% and graft survival 71% after 5 years). Graft losses due to the underlying disease were rare. Extrarenal relapses occurred in three patients with Wegener's granulomatosis, one patient with microscopic polyangiitis, and three patients with SLE, but were less frequent compared with the period with chronic dialysis therapy. Autoantibody levels in patients with SLE, Wegener's granulomatosis, or microscopic polyangiitis did not seem to influence the outcome. CONCLUSIONS: Renal transplantation should be offered to patients with autoimmune diseases. Follow-up should include the short-term control of renal and extrarenal disease activity.

Incidence of Pneumocystis carinii pneumonia after renal transplantation. Impact of immunosuppression.

The incidence and potential risk factors of Pneumocystis carinii pneumonia (PCP) in our population of renal transplant recipients were analyzed retrospectively. Of 1427 patients who received transplants between January 1986 and June 1994, 1192 were evaluated. Four different immunosuppressive regimens were applied: (1) cyclosporine (CsA) + prednisolone (Pred), (2) CsA + azathioprine (Aza, 2 mg/kg/day) + Pred, (3) CsA + Aza + antithymocyte globulin, and (4) (after December 1, 1993, European multicenter trial) FK506 + Aza (1 mg/kg/day) + Pred. No prophylaxis against PCP was performed. Before December 1, 1993, three PCPs in 494 patients on protocol 2 or 3 occurred (0.6%). Afterward, seven PCPs in 77 patients occurred (9%): three in 38 patients on protocol 2 (7.8%) and four in 28 patients on protocol 4 (14.3%). Comparing patients with PCP on CsA and FK506, the mean Aza dose was 2.40 and 1.32 mg/kg/day, five and two patients received additional steroids, antibody treatment was used in three and no patients, and CMV infections occurred in five and two patients, respectively. The incidence of PCP with a moderate CsA-based immunosuppressive regimen is low and seems to occur only in cases of additional immunosuppressive cofactors. Despite a general increase of PCP, its incidence was highest in patients on FK506 with fewer immunosuppressive cofactors. Thus, prophylaxis against PCP after renal transplantation should be performed, if not in every renal transplant recipient, at least in case of treatment with additional steroids, antibodies, or FK506.

How best to use tacrolimus (FK506) for treatment of steroid- and OKT3-resistant rejection after renal transplantation.

Nineteen patients with biopsy-confirmed ongoing acute rejection of renal allografts were converted from standard immunosuppression to FK506. Eight grafts showed vascular rejection and 11 had cellular rejection on biopsy. All patients had already received intravenous high-dose steroid treatment. Ten patients also had additional OKT3 rescue therapy. Initial FK506 doses were 0.13 +/- 0.06 mg/kg/day; the FK506 whole blood trough level after 3 days of treatment was 9.3 +/- 4.5 ng/ml. After conversion to FK506 all but four patients also received azathioprine, 1.5-2 mg/kg/day, and all patients received oral prednisolone. Concomitant with initiation of FK506, an anti-infective prophylaxis was prescribed, consisting of ganciclovir and trimethoprim/sulfamethoxazole. Sixteen out of 19 of the grafts (84%) were rescued successfully, including two grafts of patients already on hemodialysis at the time of conversion. Graft function of the responders improved from an average serum creatinine level of 364 +/- 109 mumol/L to 154 +/- 49 mumol/L. Of the patients receiving high-dose steroids alone prior to FK506 initiation, 8/9 responded to FK506 treatment, compared with 8/10 of those who had also received OKT3. During the mean follow-up of 35 weeks after conversion, no clinically apparent cytomegalovirus infection and no pneumonia were seen. Treatment with FK506 may successfully suppress ongoing acute rejection, even if antilymphocyte preparations have failed. FK506 can be used at a lower dose than so far recommended without impairing the antirejection potential. An additional anti-infective prophylaxis seems effective in preventing severe complications in the first months after rejection therapy.

The long-term course of hepatitis C after kidney transplantation.

Patients with chronic hepatitis run the risk of developing progressive liver disease during immunosuppressive therapy after kidney transplantation. To determine the impact of chronic hepatitis C on morbidity and mortality we analyzed 162 anti-HCV positive of 1241 renal-grafted patients (prevalence 13.1%; 84.9% HCV RNA positive) regularly surveyed in our outpatient clinic between 1992 and 1994. The mean age at transplantation was 44.5 (6-69) years, and follow-up after grafting was 7.4 (0.1-23.9) years. The immunosuppressive regimen and frequency of rejection episodes in HCV-infected patients were comparable to the total population. Only 4.3% (5/117) of the anti-HCV positive, HBV negative patients living with functioning grafts developed a markedly compromised liver function. Fifteen (9.3%) of the HCV-infected patients died, but none suffered from posthepatitic cirrhosis. An additional retrospective analysis of causes of death after transplantation prior to 1992 revealed that liver disease had only been responsible for 2% of the deaths (7 of 324) in the HBsAg negative population (n= 1901). In contrast, the predominant cause of death in the HBsAg positive population (n=76) was posthepatitic cirrhosis in 58% (15 of 26). Thus, kidney transplantation in patients with replicative hepatitis C and normal liver function appears to be justified because of low early and late morbidity and mortality due to chronic liver disease. HBV infection and hemosiderosis substantially increase the risk of chronic liver disease in renal transplant recipients with hepatitis C.

Recurrent immunoglobulin A nephropathy after renal transplantation: a significant contributor to graft loss.

BACKGROUND: Although most transplanted patients with underlying IgA nephropathy (IgAN) develop histological recurrence, its clinical relevance is considered low. METHODS: We performed a single-center analysis of 61 renal transplant patients with IgAN. RESULTS: Forty-four percent of the patients showed a stable graft function. Progressive graft dysfunction apparently due to recurrent IgAN occurred in 23% of the patients (16% required dialysis). Five patients were retransplanted, and three again developed dialysis-dependent renal failure apparently due to recurrent IgAN. In 20% of the patients, chronic transplant dysfunction was due to other reasons, whereas no reason was identified in 13% of the patients. Neither findings before transplantation, the ACE genotype, the type of immunosuppression, nor the course after transplantation predicted transplant dysfunction due to recurrent IgAN. Follow-up after transplantation was longer in the group with dysfunction due to recurrent disease than in the group with dysfunction due to chronic rejection or in the stable group. CONCLUSION: Recurrent IgAN is a clinically relevant problem in renal transplant patients. Its importance may have been underestimated in the past due to inadequate lengths of follow-up.

Drug interactions with valproic acid.

Valproic acid undergoes drug-drug interactions with most of the commonly used anticonvulsants. Since it possesses a wide range of indications, concomitant use with other anticonvulsants, and hence interactions, are not infrequent. Many of these interactions are reciprocal and may have important therapeutic consequences. Valproate acts as a protein binding displacer and/or metabolic inhibitor with respect to a number of other anticonvulsants (phenobarbitone, primidone, phenytoin). Inhibition of metabolism would, in most instances, result in a decrease of the dose requirements of the affected drugs. Valproate is a low clearance drug primarily eliminated by metabolism. Its metabolism is highly inducible by some of the major anticonvulsants (e.g. carbamazepine, phenytoin). Valproate is also highly protein bound in plasma and thus is displaced by salicylates and free fatty acids. However, displacement alone, unlike induced metabolism, should not affect the drug's dose-response relationship.