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R Saral

Publications and source records attributed to R Saral.

At least 37 records · Page 2Linked to original sources
PubMed1991

Strategies to prevent or control infections after bone marrow transplants.

Patients receiving bone marrow transplants are at risk of life-threatening infections early post-transplant. This predisposition results from extensive mucosal damage and severe granulocytopenia. Common causes of infection include bacteria and fungi. Infections with opportunistic pathogens occur later and are associated with defects in cellular and/or humoral immunity. The most common sites of infections are the gastrointestinal tract, oropharynx, lung, skin and indwelling vascular catheters. Empiric approaches designed to treat common bacterial and fungal pathogens are generally effective as are measures designed to prevent dissemination of infections. These approaches are also used to prevent fungal infections.

Bacterial Infections↗
PubMed1990

Bone marrow graft engineering by counterflow centrifugal elutriation: results of a phase I-II clinical trial.

In an attempt to reduce the incidence and severity of acute graft-versus-host disease (GVHD), we have decreased the number of bone marrow (BM) lymphocytes in the donor marrow graft before bone marrow transplantation (BMT) using counterflow centrifugal elutriation (CCE). In a phase I-II clinical trial, 23 patients received lymphocyte-depleted BM allografts from their HLA-identical, mixed lymphocyte culture (MLC)-nonreactive sibling donors. The patients entered in the study were deemed to be at high risk for treatment failure on the basis of age (greater than 30 years; median, 39 years) and the result of our skin explant assay predictive of acute GVHD. Patients predicted not to develop acute GVHD by this assay were excluded from this study. All patients received a standard lymphocyte dose of 0.5 x 10(6) morphologic lymphocytes per kilogram ideal body weight (IBW) in the marrow graft and were maintained on cyclosporine A (CsA) immunosuppression for 170 days after BMT. Prompt hematopoietic recovery occurred in 22 of 23 patients with a median time to an absolute neutrophil count (ANC) greater than or equal to 500/microL of 21 days. Donor cell engraftment was subsequently verified by cytogenetic and/or DNA analysis in all of 21 evaluable patients. No patient developed systemic acute GVHD. Only five (22%) developed cutaneous GVHD (clinical stage 1) that required steroid treatment, including one patient who failed to engraft. The median follow-up of the patients enrolled in this study is 14 months (range, 5 to 20 months). Actuarial survival 1 year after BMT is 83%. Thus, in two consecutive clinical trials using CCE to deplete donor BM of alloreactive lymphocytes (1.0 x 10(6) versus 0.5 x 10(6) lymphocytes/kg), we have demonstrated that the procedure does not interfere with BM engraftment and is effective in decreasing the incidence and severity of acute GVHD. Furthermore, comparison of these studies has revealed a differential dose response relationship between the number of graft lymphocytes, protection of engraftment, and induction of acute GVHD. Although there appears to be a modest relationship between lymphocyte dose and time to hematopoietic recovery, the 50% reduction in lymphocyte dose from that used in our previous trial resulted in a marked decrease in acute GVHD without compromising engraftment.

Adult↗
PubMed1990

Allogeneic bone marrow transplantation for patients with high-risk acute lymphoblastic leukemia.

Seventy-four consecutive patients with high-risk acute lymphoblastic leukemia (ALL) were given cyclophosphamide (CY; 50 mg/kg on each of 4 days) plus total body irradiation (TBI; 300 rad on each of 4 days) followed by a human leukocyte antigen (HLA)-identical allogeneic bone marrow transplant (BMT). Eighteen patients in first complete remission (CR1), 36 in CR2, 16 in CR3, and four in CR4 were transplanted. Patients in CR1 were transplanted 1 to 8 months (median, 3 months) after attaining CR. All 18 patients in CR1 had one or more poor risk factors: age more than 18 (N = 17), initial leukocyte count greater than or equal to 20,000 (N = 11), Ph 1 chromosome (N = 2), delay in attaining CR more than 6 weeks (N = 8), or extramedullary disease (N = 1). Of those transplanted in CR2, 72% had relapsed on therapy. The 5-year event-free survival (EFS) rates for patients transplanted in CR1, CR2, and CR3 are 42%, 43%, and 25%, respectively, at median follow-up times of 57, 54, and 72 months, respectively. Children aged less than 18 years transplanted in CR2 have a 5-year EFS rate of 54%. All CR4 patients died early after transplant. The actuarial probability of relapse is 20%, 26%, and 48% for those transplanted in CR1, CR2, and CR3, respectively. Although there was substantial transplant-associated mortality, it decreased over the decade of the study (P = .01). This study indicates that BMT offers an attractive alternative to postremission chemotherapy in patients in CR1 with poor prognostic factors and in patients in second remission.

Adolescent↗
PubMed1990

Using elutriation to engineer bone marrow allografts.

We have used elutriation to deplete lymphocytes from the marrow allografts of 64 patients to date. The first phase I trial (1 x 10(6) lymphocytes/kg IBW) was designed to test the procedure for potential toxicities, most notably, graft failure. Study 2 (1 x 10(6) lymphocytes/kg, no CsA) was expected to reduce potential toxicity incurred from long term immunoprophylaxis while study 3 was aimed at reducing the incidence of GVHD by further reducing lymphocyte dose (5 x 10(5)/kg). Graft lymphocyte dose was based on morphologic determination and was subsequently confirmed by limiting dilution analysis and flow cytometry. Although grafts were standardized solely by lymphocyte dose, the product was more uniform than the original harvested BM with respect to other cell populations. Nearly all study I (n = 40) and study III (n = 20) patients engrafted with a median time to ANC greater than 500/ul of 19 days. Three of the 4 patients consecutively enrolled in study II failed to engraft, thus terminating the trial. While a moderate proportion of study I patients had AGVHD (44%) with attendant morbidity, only 20% of study III patients were found to have mild AGVHD (less than or equal to stage I). To date, this cohort has no organ or chronic GVHD and no GVHD-associated morbidity. Median follow-up times for patients in studies I and III are 27 and 11 months, respectively. Overall actuarial survival (n = 60) is 42% at 38 months (38% study I, 80% study III). Good prognosis study I patients experienced 45% actuarial survival versus 9% in the poor prognostic group. While lymphocyte depletion has been effective in reducing the incidence and severity of AGVHD, new strategies are needed to address the issue of disease relapse. As with other methods, lymphocyte depletion by elutriation caused an increased rate of leukemia relapse. The actuarial probability of remaining in remission for recipients of elutriated marrow containing 1 x 10(6) and 5 x 10(5) lymphocytes/kg, respectively, were 60% and 46% at 16 months. Elutriation provides a rapid, reproducible and flexible methodology for graft manipulation which has been effective in reducing the incidence and severity of AGVHD. However, if lymphocyte depletion is to fulfill its promise as a means of reducing the overall morbidity of allogeneic BMT, new strategies may be needed to address the issue of relapse. These may include changes in marrow ablative therapy and post-graft immunosuppression. Equally as important may be the ability to further manipulate accessory cells and lymphoid populations presently excluded from the graft.

Adult↗
PubMed1990

Management of infectious complications of acute leukemia and antileukemia therapy.

The patient with acute leukemia is predisposed to infection by bone marrow failure that leads to absence of granulocytes, by extramedullary leukemia infiltration that leads to barrier breakdown, and by cytotoxic antileukemia therapy that exaggerates both the hematopoietic and the tissue mucosal defects. Empiric approaches tailored to treat commonly occurring bacterial and fungal infections have successfully decreased the morbidity and mortality from overwhelming infection in these compromised patients. More recently, prophylaxis directed against dissemination of pathogens from specific sites has had a positive impact in preventing the clinical and microbiological manifestations of infection during profound aplasia. The approaches that have been successful in preventing and treating bacterial infections are being applied to the increasingly prevalent fungal infections that occur later during the granulocytopenic course, with encouraging results.

Acute Disease↗
PubMed1990

Cure of acute myelocytic leukemia in adults: a reality.

Adult acute myelocytic leukemia (AML) is a curable disease in responsive patients with aggressive treatment in remission. Over the past decade at the Johns Hopkins Oncology Center, AML has been treated with either allogeneic bone marrow transplantation or with intensive timed sequential treatment using high dose cytarabine in remission. With either treatment modality comparable cure rates were obtained. The role, if any, of randomized trials to adequately determine the preferred treatment for appropriate patients has yet to be defined.

Adolescent↗
PubMed1990

Density-gradient separation for 4-hydroperoxycyclophosphamide purging of autologous bone marrow grafts.

We studied density-gradient separation of autologous bone marrow grafts in preparation for ex vivo 4-hydroperoxy-cyclophosphamide (4-HC) purging. A two-step procedure of buffy coat isolation followed by Ficoll-diatrizoate separation was used. Buffy-coat cells were isolated primarily either using the COBE 2991 Blood Cell Processor or Haemonetics 30 Cell Separator. All density-gradient separations were performed using the COBE 2991. The nucleated cell recoveries after buffy-coat isolation were 44.3 +/- 10.4% and 85.1 +/- 10.5% (+/- standard deviation, P less than 0.001) for the Haemonetics 30 and COBE 2991 isolated grafts, respectively. The final nucleated cell recoveries after density-gradient separation for these two buffy-coat techniques were 24.2 +/- 10.1% and 29.5 +/- 14.7% (p = 0.30). Compared to manual density-gradient separation, the techniques using the COBE 2991 recovered slightly higher numbers of nucleated cells and CFU-GM. The red blood cell concentration of the 4-HC incubation mixture was 1.0 +/- 0.6% and the CFU-GM survival after treatment was 2.4 +/- 2.6%. The variability in CFU-GM survival after 4-HC incubation of the density-gradient separated grafts appears less than previous experience treating buffy-coat cells. Density-gradient separation of autologous bone marrow appears to provide a more uniform treatment with 4-HC and may improve the clinical transplant course of the autograft recipient.

Bone Marrow↗
PubMed1990

Oral complications of cancer therapies. Management of acute viral infections.

Oral ulcerations are frequently observed in cancer patients receiving chemotherapy or radiation therapy. Herpes simplex virus is the most common viral pathogen association with lesions. Reactivation of latent virus is responsible for the vast majority of culture-positive infections. The natural history of this virus has been well studied in selected patient populations. These infections may cause local complications and, if untreated, may not heal for weeks. Reactivation of the virus may occur predictably in patients after bone marrow transplantation or acute leukemia. Recognition that herpes simplex virus is present in oral lesions is of importance because of the availability of safe, effective antiviral therapy. Prospective, randomized, double-blind clinical trials have demonstrated that acyclovir is the most effective agent to treat or prevent herpes simplex virus infections in immunocompromised patients.

Acute Disease↗
PubMed1989

Allogeneic bone marrow transplantation, zidovudine, and human immunodeficiency virus type 1 (HIV-1) infection. Studies in a patient with non-Hodgkin lymphoma.

Human immunodeficiency virus type 1 (HIV-1)-infected patients with non-Hodgkin lymphoma are classified as having the acquired immunodeficiency syndrome (AIDS). Allogeneic bone marrow transplantation is a successful therapy for patients with lymphoma who have a poor prognosis. Combined therapy with allogeneic bone marrow transplantation and the antiviral drug zidovudine has the potential advantage of protecting the new donor hematopoietic-lymphoid and monocyte-macrophage cells from HIV-1 infection. A 41-year-old man infected with HIV-1 who had lymphoma was treated with high-dose cyclophosphamide and total body irradiation followed by allogeneic bone marrow transplantation. Before transplantation he received high-dose zidovudine for 2 weeks (5 mg/kg body weight intravenously every 4 hours) and after transplantation he received a lower maintenance dose (1.33 mg/kg body weight intravenously every 4 hours). No untoward toxicities attributable to zidovudine were observed. Bone marrow engraftment occurred on day 17. Chromosome and restriction fragment length polymorphism analyses demonstrated complete chimerism. Peripheral blood mononuclear cells and bone marrow samples were negative for HIV-1 by culture and polymerase chain reaction gene amplification 32 days after transplantation. The patient died 47 days after transplantation because of tumor relapse. Analysis of autopsy tissue showed no evidence of HIV-1 by either culture (brain, bone marrow, lymph node, and tumor specimens) or by polymerase chain reaction gene amplification for HIV-1 RNA and DNA sequences (brain, bone marrow, heart, kidney, liver, lung, rectosigmoid, spleen, and tumor specimens). Immunologic monitoring showed loss of HIV-1 antibody. Adoptive immunologic transfer was shown to be present to both tetanus and diphtheria antigens. Our case suggests that the HIV-1-infected recipient cells may have been eradicated secondary to the bone marrow ablative chemo-radiotherapy and that zidovudine may be able to prevent the establishment of HIV-1 infection in donor hematopoietic-lymphoid cells.

Adult↗
PubMed1989

The eye in bone marrow transplantation. III. Conjunctival graft-vs-host disease.

Of a series of 263 patients undergoing allogeneic bone marrow transplantation (BMT), 24 patients developed conjunctival involvement by graft-vs-host disease (GVHD). In each case, a distinct-appearing conjunctivitis developed that representing GVHD of the conjunctiva. In 19 cases (79%), conjunctival GVHD presented with pseudomembrane formation due to loss of the conjunctival epithelium; in 4 of these cases, the corneal epithelium was lost as well. Nineteen patients developed this feature in association with acute GVHD, and mortality among these patients was 89.5%. Kaplan-Meier analysis of survival demonstrated a decreased survival of patients with conjunctival involvement compared with all marrow transplant recipients and compared with all patients with GVHD. However, survival was similar to that seen in patients with severe systemic GVHD (overall stages II through IV). Five patients developed conjunctival GVHD in association with chronic GVHD, and all had severe chronic GVHD. four of these five with chronic GVHD subsequently died. Conjunctival involvement by GVHD represents a distinct clinical finding and is a marker for severe systemic involvement by GVHD. A clinical staging system for ocular involvement was formulated.

Biopsy↗
PubMed1989

Pharmacokinetics of busulfan: correlation with veno-occlusive disease in patients undergoing bone marrow transplantation.

Busulfan is an alkylating agent that is widely used in preparative regimens for bone marrow transplantation (BMT). We developed a high-performance liquid chromatographic (HPLC) assay for the determination of plasma busulfan concentrations in 30 patients who received oral doses of 1 mg/kg. Concentrations were fit by a one-compartment pharmacokinetic model with first-order absorption. The pattern of absorption and elimination varied widely between patients, with peak concentrations ranging from 1.2 to 10.4 mumol/l (mean, 4.25 +/- 2.49). The elimination half-life ranged from 58 to 433 min (harmonic mean, 140 min). The AUC contributed by a single oral dose ranged from 606 to 5,144 mumol-min/l (mean, 2,012 +/- 1,223). Patients were evaluated for the development of veno-occlusive disease (VOD), a treatment complication that occurs in 20% of patients undergoing BMT and causes 10% of transplantation-related deaths. All six patients who developed VOD had an AUC greater than the mean, and five of them had an AUC that was greater than 1 SD above the mean. The occurrence of VOD was highly correlated with an increased AUC (greater than 1 SD above the mean) (X2 = 18; P less than 0.0001). Using multivariate logistic regression, no other statistically significant pharmacokinetic predictor of VOD was found. The tenfold variability in the busulfan AUC and the statistical association of increased AUC with the development of VOD suggest a possible role for therapeutic monitoring in this setting.

Absorption↗
PubMed1989

Longitudinal changes in pulmonary function following bone marrow transplantation.

We prospectively followed a well characterized cohort of patients post-bone marrow transplantation for changes in pulmonary function. Thirty-four recipients without respiratory symptoms were available for follow up with a mean of two years. Spirometry and other measures of lung volume were well preserved following bone marrow transplantation. A progressive 11.9 percent decline in percent predicted diffusing capacity per year occurred. Age, cigarette smoking, type of cytoreductive therapy, type of GVHD prophylaxis, and the occurrence of AGVHD did not affect longitudinal changes in pulmonary function. Patients receiving transplants for CML developed a highly significant fall in diffusing capacity. Asymptomatic patients with CGVHD developed evidence of progressive obstructive ventilatory impairment. This suggests a subclinical spectrum of patients who may progress to the development of bronchiolitis obliterans and respiratory failure post-bone marrow transplantation.

Adult↗
PubMed1989

Herpes zoster infection after autologous bone marrow transplantation.

One hundred fifty-three patients who underwent autologous bone marrow transplant (ABMT) were studied retrospectively to determine the frequency, outcome, and risk-factors associated with varicella-zoster infections (VZV). Forty-three patients (28%) developed VZV infection after transplant. The median onset of infection was the fifth month, with 91% of cases occurring within the first year. Thirty-three patients (77%) had localized herpes zoster, and ten patients (23%) had varicella. Cutaneous dissemination developed in 15% of patients and probable visceral dissemination developed in 5%. Overall morbidity was 25% and included scarring, alopecia, postherpetic neuralgia, and neurologic dysfunction. There were no deaths from VZV infection. The majority of patients (79%) were treated with intravenous (IV) acyclovir. The only significant risk factor associated with VZV infection was the underlying disease. VZV infection occurred most frequently in patients with Hodgkin's and non-Hodgkin's lymphoma (46%) as compared with patients with leukemia (23%) or solid tumors (9%) (P less than .002). The frequency of VZV infection in ABMT patients appears to be comparable to that reported for allogeneic BMT patients and other immunocompromised patients.

Actuarial Analysis↗
PubMed1989

Endothelial-cell injury in cutaneous acute graft-versus-host disease.

The presence of an erythematous skin rash and hemorrhagic complications in acute graft-versus-host disease (GVHD) suggest that the vasculature may be involved in the immunopathologic process. We reviewed endothelial and vascular histopathologic changes on light microscopy and on immunoperoxidase stained sections of skin biopsies obtained from 41 HLA-identical allogeneic marrow transplant recipients with at least grade 2 GVHD. Biopsies taken from 14 allogeneic HLA-identical bone marrow transplant recipients who never developed GVHD were used as controls. Sections were evaluated for evidence of immunologic vascular injury using the rank file analysis of histologic features, expression of HLA-DR antigen, and the distribution of fibrin and factor VIII-related antigen (F VIII RAg). Patients with acute GVHD had significantly greater intimal lymphocytic infiltrates, perivascular nuclear dust deposition, perivascular F VIII Rag extravasation and deposition and vascular proliferation than controls. We find significantly greater endothelial injury in GVHD patients, which may represent primary immunologic injury to the vasculature. The clinical findings in acute GVHD probably result from cumulative endothelial as well as epithelial injury.

Acute Disease↗
PubMed1989

Second bone marrow transplantation after leukemia relapse in 11 patients.

Since June 1977 eight patients with acute leukemia and three with chronic myelogenous leukemia (CML) have undergone cytoreductive therapy prior to a second allogeneic or syngeneic bone marrow transplantation (BMT). The median age was 24 years (range 7-49 years) and the median time to second BMT was 495 days (range 122-1887 days). Prompt hematopoietic recovery was documented in 11/11 patients and verified by cytogenetic analysis in 7/11. Early death (less than 100 days) was the result of sepsis in one, veno-occlusive disease in one and interstitial pneumonitis in two. Of seven patients who survived beyond 1 year, two patients subsequently died, one as a result of acute respiratory failure and one of leukemia relapse. Five are currently disease-free at 8+, 20+, 42+, 49+ and 72+ months after the second BMT. In this patient population which is at high risk for resistant disease and treatment-related toxicity, a second preparative therapy and BMT may offer a durable disease remission with tolerable toxicity.

Adolescent↗
PubMed1989

Allogeneic bone marrow transplantation after high-dose busulfan and cyclophosphamide in patients with acute nonlymphocytic leukemia.

Ninety-nine patients with acute nonlymphocytic leukemia (ANLL) received HLA-identical bone marrow transplants (BMTs) from sibling donors after preparation with high doses of busulfan and cyclophosphamide. Forty-nine patients were transplanted in first complete remission (CR), and 50 patients were transplanted in second and third CR and early relapse. Fifty-three received one of three regimens containing primarily low-dose cyclophosphamide (group I) for graft-v-host disease (GVHD) prophylaxis; since March 1983, 46 patients received intravenous (IV) cyclosporine (group II). After December 1983, only cytomegalovirus (CMV)-seronegative blood products were used in appropriate patients, and since April 1984 patients seropositive for herpes-simplex virus (HSV) and CMV received high-dose acyclovir prophylaxis. For patients transplanted in first CR, there was a significantly lower incidence of acute GVHD (P = .005) and deaths related to GVHD and interstitial pneumonitis (P = .001) in patients in group II. This was reflected in an improved Kaplan-Meier probability of disease-free survival (DFS) in the 22 patients transplanted in group II as compared with the 27 patients in group I (64% +/- 10% v 30% +/- 9%, P = .017). The probability of remaining in remission was slightly lower in group II (82% +/- 9% v 94% +/- 6%, P = .479). For patients transplanted in second and third CR and early relapse, the incidence of acute GVHD (P = .026) and deaths related to GVHD and interstitial pneumonitis was significantly lower in group II (P = .029); the probability of remaining in remission was also less (47% +/- 15% v 91% +/- 15%, P = .022). However, the probability of DFS was not significantly different between the two groups (26% +/- 10% v 35% +/- 18%, P = .957). We conclude that transplantation for patients in first CR who received IV cyclosporine therapy is effective treatment; patients with more refractory disease treated with the same cyclosporine regimen (group II) had a lower incidence of GVHD than those treated in group I, but survival did not improve because of an increase in the number of relapses and other nonleukemic complications.

Acute Disease↗
PubMed1989

Efficacy of ex vivo purging for autologous bone marrow transplantation in the treatment of acute nonlymphoblastic leukemia.

We used an in vitro measure of drug activity to predict the efficacy of ex vivo purging of leukemic cells from autologous bone marrow grafts. We previously found that the myeloid progenitor cell (CFU-GM) content of the marrow grafts after ex vivo purging with 4-hydroperoxycyclophosphamide (4-HC) correlates with time to hematologic recovery after autologous bone marrow transplantation in patients with acute nonlymphoblastic leukemia. We observed that variable red blood cell concentration of the bone marrow incubation mixture results in differential cytotoxic activity of 4-HC. The CFU-GM content of the graft after the ex vivo treatment is a measure of this 4-HC activity. We analyzed the disease-free survival of 45 patients with acute nonlymphoblastic leukemia undergoing autologous bone marrow transplantation with 4-HC purged grafts. Patients who relapsed after transplantation had 4.2 +/- 1.1% of graft CFU-GM surviving the ex vivo purge, compared with 1.1 +/- 0.4% for patients who achieved a sustained remission (P = .06). Twenty-three patients with a CFU-GM content after 4-HC purging of greater than 1% of the pretreatment value had an actuarial disease-free survival of 12%, compared to 36% for 22 patients with a less than or equal to 1% CFU-GM content after purging (P = .006). Therefore, percent CFU-GM survival as a measure of 4-HC cytotoxicity identified a group of patients with insufficient purging. Although no randomized clinical trials have documented the need for ex vivo purging, our results suggest that effective bone marrow purging is important for the optimal application of autologous transplantation in the treatment of acute nonlymphoblastic leukemia.

Age Factors↗