Michael S. Kennedy

Acute renal toxicity with combined use of amphotericin B and cyclosporine after marrow transplantation

The role of cyclosporine alone or in combination with amphotericin B in the development of renal toxicity was evaluated in 47 marrow transplant recipients. Cyclosporine alone was given to 21 patients and 10 received cyclosporine plus amphotericin B. These were compared with 16 patients who received methotrexate and amphotericin B. Serum creatinine doubled within 14–30 days in 8 of 21 patients who received only cyclosporine. Of 16 patients given amphotericin B in conjunction with methotrexate, only 3 doubled their serum creatinine within 5 days of starting amphotericin B. In contrast, of 10 patients who received amphotericin B in combination with cyclosporine, 5 doubled and 3 tripled their serum creatinine within 5 days. This increase in creatinine was significantly greater than that seen in patients receiving cyclosporine alone or methotrexate and amphotericin B combined. These results suggest that administration of cyclosporine and amphotericin B simultaneously should be undertaken with caution to avoid severe renal toxicity.

Profound hypomagnesemia and renal magnesium wasting associated with the use of cyclosporine for marrow transplantation

We prospectively studied 41 marrow transplant patients to evaluate the possible association of hypomagnesemia with cyclosporine immunosuppressive therapy. During the 3 months posttransplant the mean nadir serum magnesium level was 1.06±0.16 mEq/L in 24 patients treated with cyclosporine and 1.33±0.13 in 14 patients treated with methotrexate (P<0.0001). Eleven of 24 patients receiving cyclosporine versus 1 of 14 patients receiving methotrexate had magnesium levels <1 mEq/L, or were begun on replacement therapy for presumed symptomatic hypomagnesemia (P<0.02). Agents known to be associated with hypomagnesemia, aminoglycosides and amphotericin B, were given in both lesser quantity and frequency to cyclosporine-treated patients than to methotrexate-treated patients. Hypomagnesemic patients treated with cyclosporine had inappropriately elevated urine magnesium excretion. Renal magnesium wasting may be added to the spectrum of nephrotoxicity resulting from cyclosporine. Several adverse reactions previously attributed to cyclosporine may be secondary to magnesium deficiency.

Treatment of human acute graft–versus–host disease with antithymocyte globulin and cyclosporine with or without methylprednisolone

Forty-eight patients with hematologic malignancies treated by allogeneic marrow transplantation developed acute graft-versus-host disease (GVHD), grades II-IV, despite prophylaxis with methotrexate. They were treated with a combination of antithymocyte globulin (ATG) and cyclosporine (CsA), with or without the addition of methylprednisolone (MP). Thirty patients had received HLA-identical and 18 HLA-nonidentical transplants. Median onset of GVHD was day 13 (range 8-60) for patients with HLA-nonidentical grafts and day 18 (range 7-48) for patients given HLA-identical grafts (P = 0.01). Forty-five patients could be evaluated for response on day 7 of therapy. Among these, 13 of 27 given ATG/CSP and 6 of 18 given ATG/CSP/MP improved. Among 33 patients evaluable on day 14 of therapy 13 of 19 given ATG/CSP and 5 of 14 given ATG/CSP/MP showed improvement of GVHD. Patients given HLA-nonidentical grafts responded somewhat (although not significantly) less frequently than patients given HLA-identical grafts. Chronic GVHD developed in 16 of 18 evaluable patients given ATG/CSP and in 5 of 6 given ATG/CSP/MP. Viral, bacterial, and fungal infections were the major cause of death in both groups. Interstitial pneumonitis was more frequent among patients given ATG/CSP/MP. Survival beyond 6 months was 67% among patients treated with ATG/CSP and 25% with ATG/CSP/MP. These data indicate that a regimen of ATG/CSP is of value in the treatment of acute GVHD. The addition of MP was not beneficial and resulted in decreased survival--presumably because of excessive immunosuppression and associated complications.

Incidence of hypertension after marrow transplantation among 112 patients randomized to either cyclosporine or methotrexate as graft-versus-host disease prophylaxis

Summary We investigated the frequency of hypertension (sustained diastolic blood pressure ≥90 mmHg) in 112 patients given HLA‐identical marrow grafts. Patients were conditioned with 2 × 60 mg/kg of cyclophosphamide and 6 × 2 Gy of total body irradiation and randomized to receive as graft‐versus‐host disease prophylaxis either the standard methotrexate regimen (n= 61) or cyclosporine (n= 51), starting on day −1 as 12.5 mg/kg/d orally or as 3 mg/kg/d i.v. and later converting to p.o. when oral intake was tolerated. Kaplan‐Meier estimates indicate a 60% incidence of hypertension in the first 120 d in patients given cyclosporine (median time to onset: 4 d post transplant) compared to 20% in patients given methotrexate (P<0.0001). Multifactorial analysis using a Cox regression model showed that cyclosporine was the most significant risk factor for developing hypertension (relative risk: 32.1, P<0.0001). In addition, glucocorticoids, used for treatment of GVHD, were associated with an increased risk for hypertension (relative risk 7.2, P<0.0001). Age, sex, underlying disease, cyclosporine trough levels, and renal function had no significant association with hypertension. Early therapy of hypertension in cyclosporine‐treated patients appears to be indicated.

Correlation of hypomagnesemia with the onset of cyclosporine-associated hypertension in marrow transplant patients

Cyclosporine is known to cause hypertension, and we have recently reported that it causes hypomagnesemia and renal magnesium wasting in marrow transplant recipients. We performed a case-control study to ask whether hypomagnesemia might be related to this form of drug-induced hypertension. The charts of 188 patients treated with cyclosporine were evaluated for the development of hypertension. The 32 patients who became hypertensive were age, sex, and disease-matched with 32 cyclosporine-treated controls. Baseline serum Mg levels were normal in both groups. However at the time of development of hypertension, the hypertensive patients had a mean (+/- SD) Mg of 1.22 +/- 0.20 mEq/L versus controls 1.40 +/- 0.33 mEq/L (P less than 0.01). Serum calcium, albumin, creatinine, potassium, and cyclosporine concentrations were not different between the two groups. This study may indicate that hypertension and hypomagnesemia are coincident toxicities in cyclosporine-treated patients. Alternatively, our data support the hypothesis that acquired derangements in magnesium metabolism may contribute to the development of hypertension. Magnesium replacement may prove beneficial in the treatment and/or prevention of cyclosporine-associated hypertension.

Treatment of acute graft-versus-host disease after allogeneic marrow transplantation. Randomized study comparing corticosteroids and cyclosporine.

Seventy-seven patients (age 12 to 46 years) who underwent allogeneic marrow transplantation for hematologic malignancy or aplastic anemia and who had grade II to IV acute graft-versus-host disease despite methotrexate prophylaxis were randomly assigned to receive methylprednisolone 2 mg/kg per day intravenously (n = 39) or cyclosporine (n = 38) either 12 to 15 mg/kg per day orally or 3 to 5 mg/kg per day intravenously. In both groups, clinical and histologic evidence of graft-versus-host disease was detected at medians of 16 and 25 days, respectively. Drugs were given for a minimum of 14 days unless significant deterioration occurred. If graft-versus-host disease did not improve with this therapy, treatment with a second agent was initiated. Treatment responses were scored after reviewing clinical and laboratory data collected before, during, and after the 14-day treatment period. Possible scores were as follows: -1, worse; 0, no change; + 1, improvement in one organ system (skin, liver, gut) with no deterioration in the other two; +2, complete resolution of all involved systems. The median response score among 39 methylprednisolone-treated patients was 0. Sixteen patients (41 percent) showed response to treatment, 11 with partial and five with complete response. The median response score among 38 cyclosporine-treated patients was +1. Twenty-three patients (61 percent) showed response to treatment, 15 with partial and eight with complete response (p = 0.039). Twenty patients receiving methylprednisolone and 18 receiving cyclosporine required additional therapy. The incidence of chronic graft-versus-host disease was similar in both groups. It developed in all nonresponding patients at risk who had received secondary therapy. Among responding patients (scores +1 or +2) who were not given additional treatment, chronic graft-versus-host disease developed in eight of 11 (72 percent) receiving methylprednisolone and five of ten (50 percent) receiving cyclosporine. Survival beyond 17 months was similar in the two groups (28 percent and 24 percent, respectively). These data suggest that cyclosporine is a useful agent for the treatment of acute graft-versus-host disease, comparable in its efficacy to methylprednisolone.

Combined immunosuppression with cyclosporine and methotrexate in dogs given bone marrow grafts from DLA-haploidentical littermates

We examined the effect of methotrexate (MTX) combined with cyclosporine (CSP) on the prevention of graft-versus-host disease (GVHD) in dogs. Ten recipients were prepared for grafting with 9 Gy of total-body irradiation and given marrow and buffy coat cells from littermate donors differing for one DLA haplotype (AA → AB or AB → AC). MTX (0.4 mg/kg) was given i.v. on days 1, 3, 6, and 11. CSP was given i.m. on days 0 to 7 and orally on days 8 to 100. The dose was 15 mg/kg/day on days 0 to 25, 10 mg/kg/day on days 26 to 50, 5 mg/kg/day on days 51 to 75, and 5 mg/kg every other day on days 75 to 100. All ten dogs had sustained engraftment. Three dogs died, one with pneumonia (day 57), one with pneumonia and GVHD (day 107), and one with convulsions (day 204). Seven dogs are surviving at 210 to 493 days, and all are complete chimeras; five are well and two have chronic GHVD that developed after immunosuppressive treatment had been stopped. These results with a combination of MTX and CSP as GVHD prophylaxis are superior to those obtained previously with MTX alone in dogs given marrow grafts from DLA-haploidentical littermates.

Temporal patterns of grazers and vegetation in a temperate seagrass system

Abstract The densities of benthic vegetation and invertebrate grazers were monitored in the seagrass system dominated by Zostera marina L. and Zostera japonica Aschers. & Graebn. in Padilla Bay, Washington. The primary invertebrate grazers included the isopod Idotea resecata Stimpson, caprellid amphipods and the gastropod Lacuna variegata Carpenter. Densities of Idotea and caprellids peaked in summer, and Lacuna density reached a maximum in winter. Spatial variation in densities was great, and was in the range of four orders of magnitude during some seasons. The mean, experimentally determined, grazing rate by Idotea was 0.95 mg dry wt. m −2 day −1 . At this rate, Idotea populations alone could remove up to 8 g dry wt. eelgrass m −2 day −1 . Based upon (1) high grazer densities, (2) the results of grazing experiments, and (3) experiments and observations by others showing the significance of caprellids and Idotea , we conclude that herbivory is an important process in Padilla Bay.

Marrow transplantation for leukemia following fractionated total body irradiation. A comparative trial of methotrexate and cyclosporine

Fifty-six patients, 30-47 yr of age, with leukemia in relapse received allogeneic marrow transplants from HLA-identical siblings. All patients were treated with cyclophosphamide (120 mg/kg) and 7 daily fractions of 2.25 Gy of total body irradiation (TBI) for seven consecutive days. Nine patients (16%) are currently alive and free of disease 324-845 days from transplantation. The actuarial relapse and survival rates at 2 yr were 56% and 9.5% respectively. These data were not remarkably different from those in previous studies using 10 Gy of TBI administered as a single dose. Thirty patients were randomized to receive methotrexate (MTX) and 26 to receive cyclosporine (CSP) as postgrafting prophylaxis for acute graft-versus-host disease (GVHD). The probability of developing significant acute GVHD by day 100 post-transplant was 71% for patients in the MTX group and 45% for patients in the CSP group (p less than 0.05). The probability of relapse was 37% for patients in the MTX group and 70% for patients in the CSP group (p less than 0.05). Transplant-related deaths were more frequent in the MTX group and leukemic deaths were more frequent in the CSP group although this may have been related to an uneven distribution of high-risk patients. Long-term disease-free survival was comparable. Patients in the MTX group had more severe mucositis, more alveolar pneumonias and possibly more deaths due to complications of acute and chronic GVHD. Patients in the CSP group had a higher incidence of hypertension, neurological complications and renal dysfunction.

Monitoring of cyclosporine therapy with in vitro biological assays

We examined the correlation between cyclosporine (CsA) levels and in vitro assays of immune function and hematopoiesis. Mixed lymphocyte reaction (MLR), mitogen responses, suppressor cell (SC), cell-mediated lympholysis (CML), and erythroid colony (EC) assays were studied in dogs, and in vitro megakaryocytopoiesis was studied in mice. Serum CsA concentrations were measured by radioimmunoassay. After oral or intramuscular CsA dosing, lymphocyte proliferation, as measured by MLR, inversely correlated with in vivo serum CsA concentration. MLR responses decreased rapidly, and nearly complete inhibition coincided with peak CsA levels. While CsA concentration-related suppression of lymphocyte stimulation was also observed in mitogen-stimulated cultures, results were less predictable and similar to results with in vitro CsA addition, and higher serum CsA levels were required to achieve comparable suppression. In vivo serum or in vitro CsA levels > 300 ng/ml completely inhibited the development of cytotoxic effector cells but had no measureable effect on the expression of suppressor cells in the same cultures. Furthermore, CsA serum also caused concentration-related inhibition of EC growth. The addition of human embryonic kidney–conditioned medium, however, abrogated CsA-related inhibition of EC growth, which suggested that CsA indirectly inhibited EC growth, presumably by interfering with CsA-sensitive accessory cells. This was supported by studies in an in vitro model of murine megakaryocytopoiesis. In normal conditioned medium, megakaryocyte colonies were unaffected by the presence of CsA. However, when cells were cultured in conditioned medium prepared in the presence of CsA, profound inhibition of megakaryocyte growth was observed. These studies show that biologic assays can be used reliably to measure concentration-related changes in immunosuppressive activity of CsA. Further clinical studies are needed to evaluate the usefulness of pharmacodynamic monitoring of CsA therapy.