Efficacy of clarithromycin in preventing viridans streptococcal bacteremia following autologous stem cell transplantation.

BACKGROUND: In a study involving 200 patients, we previously found that 17.5% of patients developed viridans streptococcal (VS) bacteremia following autologous peripheral blood stem cell transplantation (aPBSCT) when ciprofloxacin or ciprofloxacin plus ampicillin was used for prophylaxis. PATIENTS AND METHODS: A retrospective evaluation of 100 consecutive recipients of aPBSCT was conducted to ascertain the incidence and outcome of VS bacteremia when a combination of ciprofLoxacin and clarithromycin was utilized for antimicrobiaL prophylaxis following transplantation. The 200 patients from our previous study, in which ciprofloxacin alone or ciprofloxacin with ampicillin was used for prophylaxis, were combined with the current group for the purpose of statistical analysis. RESULTS: Streptococcus mitis was isolated from the blood of five individuals at a median of 5 days following stem cell infusion. Each of these patients was neutropenic and presented with fever. Three isolates demonstrated intermediate resistance to macrolides in vitro. However, all episodes of bacteremia were treated successfully with systemic antibiotic therapy. CONCLUSION: Age, duration of neutropenia, type of underlying malignancy and type of conditioning chemotherapy regimen failed to have a significant impact on subsequent VS bacteremia. Only female sex and use of ciprofloxacin without clarithromycin as antimicrobiaL prophyLaxis predicted a significantly increased risk of VS bacteremia in both univariate and Logistic regression analyses.

Cytoreduction and stem cell mobilization with a regimen of paclitaxel, etoposide and cyclophosphamide followed by autologous transplantation using a preparative regimen of busulfan, etoposide and cyclophosphamide for patients with advanced lymphoma.

Forty-one patients with advanced Hodgkin's disease or intermediate or high-grade lymphoma, after having received standard salvage chemotherapy, were treated with a nonablative high-dose regimen of paclitaxel, etoposide and cyclophosphamide (D-TEC) to optimally cytoreduce their disease and simultaneously mobilize peripheral blood stem cells. This regimen produced a response rate of 78% (35% complete and 43.2% partial response) and mobilized sufficient peripheral blood stem cells in 94% of the patients. Thirty-two of these patients then underwent autologous progenitor cell transplantation after ablative conditioning with busulfan, etoposide and cyclophosphamide. Actuarial overall survival at 61 months was 71.9% with an event-free survival (EFS) of 65.6%. Median EFS was 24.4 months. EFS of patients responsive to salvage chemotherapy was 75% at 61 months, compared to 33.3% at 51.4 months in patients resistant to salvage chemotherapy. EFS of patients with disease sensitive to D-TEC was 75% at 61 months compared to 0% at 13.1 months in patients resistant to D-TEC. In a multivariate analysis, the only significant parameter for transplant outcome was sensitivity to D-TEC (p = 0.016), but not sensitivity to standard salvage chemotherapy. Aggressive cytoreduction may permit even those patients who are resistant to standard salvage chemotherapy to become successful transplant candidates.

Idiopathic pneumonia syndrome following myeloablative chemotherapy and autologous transplantation.

OBJECTIVE: To report the outcome as well as the clinical, radiographic, and pathologic features of idiopathic pneumonia syndrome (IPS) following autologous peripheral blood stem cell transplantation (aPBSCT). CLINICAL FINDINGS: A total of 271 patients with a variety of underlying malignancies received busulfan-containing myeloablative chemotherapy prior to aPBSCT; none of these patients received total body irradiation. Ten individuals developed IPS, with a median time of onset of 102 days after stem cell infusion. The major clinical and radiographic findings included an acute or subacute onset of dyspnea, cough, hypoxemia, and bilateral or unilateral infiltrates with or without pleural effusion. Pathologic findings consisted mainly of diffuse interstitial pneumonitis, organizing alveolitis, and cellular atypia. Nine patients diagnosed with IPS were treated with high doses of glucocorticoids parenterally. Despite heroic measures, eight patients died of IPS. The two remaining individuals recovered without experiencing significant long-term pulmonary sequelae. DISCUSSION: Chronic low-dose busulfan therapy results in lung injury in 4-6% of patients after several years of treatment and once the cumulative dosage begins to approach 3g. High-dose, short-course busulfan (16 mg/kg)-containing conditioning chemotherapy prior to aPBSCT can also be complicated by IPS. IPS differs from lung damage due to chronic busulfan therapy by its earlier onset, an acute or subacute rather than indolent presentation, characteristic clinical and radiographic features, and lack of multinucleated giant cells on pathologic review. The pathophysiology of IPS secondary to high-dose busulfan-containing myeloablative regimens is not known, but cell-mediated immune reactions and release of cytokines may contribute to the lung injury. Mortality is high (80%) despite the use of heroic measures, including mechanical ventilation. Some patients, however, can respond to high doses of parenteral corticosteroid therapy. CONCLUSIONS: IPS following high-dose, short-course busulfan-containing regimens exhibits unique clinical, radiographic, and pathologic features that differ from lung damage characteristic of chronic, low-dose busulfan therapy. Mortality from this complication is 80%, but some patients survive without long-term pulmonary sequelae following early treatment with glucocorticoids.

Dose-intense paclitaxel, etoposide and cyclophosphamide: a safe and active regimen for tumor cytoreduction and stem cell mobilization in metastatic breast cancer.

Patients with metastatic breast cancer in complete remission are the ones most likely to have an improved outcome with subsequent high-dose chemotherapy and autologous peripheral blood stem cell transplantation (HDC-PBSCT). Peripheral blood stem cells are usually procured following mobilization with single agent chemotherapy and colony-stimulating factor support. We utilized a dose-intense regimen of paclitaxel 200 mg/m2 i.v., etoposide 60 mg/kg i.v., and cyclophosphamide 3 g/m2 i.v. (TEC) followed by daily administration of granulocyte colony-stimulating factor. The aim was not only to mobilize stem cells but also to achieve optimal tumor cytoreduction prior to HDC/PBSCT. One hundred consecutive patients with metastatic breast cancer received 257 cycles of TEC between March 1994 and June 1997, with the aim of collecting 5 x 106 CD34-positive cells/kg usually following the second cycle of chemotherapy. Patient characteristics included a median age of 45 years, a median of two organ systems involved by disease, a median of two prior chemotherapy regimens and eight prior chemotherapy cycles, and a median interval of 8 months from diagnosis of metastases to first cycle of TEC. There were 61 febrile episodes during neutropenia and 13 of these were associated with bacteremia or fungemia. Mortality rate was 1%. An adequate number of stem cells was collected in 90% of patients. The overall response rate of the tumor was 58.8% with 23.7% complete responders among 97 evaluable patients. Multivariate analysis demonstrated chemosensitivity to the most recent standard chemotherapy regimen administered for metastatic disease, an ECOG performance score of 0 as opposed to 1, 2 or 3, and involvement by disease of only one organ system as significant variables for achieving a complete remission with TEC. This novel dose-intense regimen was safe and well tolerated, highly active against metastatic breast cancer, and capable of excellent stem cell mobilization. Bone Marrow Transplantation (2000) 25, 123-130.

Incidence and outcome of vancomycin-resistant enterococcal bacteremia following autologous peripheral blood stem cell transplantation.

A retrospective evaluation of 321 consecutive recipients of high-dose chemotherapy (HDC) and autologous peripheral blood stem cell transplantation (PBSCT) was conducted to ascertain the incidence and outcome of vancomycin-resistant enterococcal (VRE) bacteremia. Ten patients developed VRE bacteremia at a median of 6 days following PBSCT. Nine isolates were Enterococcus faecium and one was E. faecalis. The median duration of bacteremia was 5 days. The central venous catheter was removed in seven individuals. Nine patients were treated with a variety of antimicrobial agents including quinupristin-dalfopristin, chloramphenicol, doxycycline, oral bacitracin, co-trimoxazole, and nitrofurantoin. Bacteremia resolved without adverse sequelae in seven patients. Two individuals who died of other causes had persistent or relapsed bacteremia at the time of death. An additional patient suffered multiple relapses of VRE bacteremia and died as a result of VRE endocarditis 605 days following PBSCT. Mortality as a direct result of VRE bacteremia was 10% in this series. The optimal type and duration of treatment of VRE bacteremia has not been clearly defined. Therefore, we perform weekly stool surveillance cultures for VRE in our hospitalized transplant population and apply strict barrier precautions in those individuals in whom stool colonization has been identified. Furthermore, the empiric use of vancomycin has been restricted. Bone Marrow Transplantation (2000) 25, 147-152.

Kaposi's sarcoma following allogeneic hematopoietic stem cell transplantation for chronic myelogenous leukemia.

Unlike solid organ transplantation, Kaposi's sarcoma (KS) occurs rarely following hematopoietic stem cell transplantation (HSCT). In fact, only 5 cases of KS have been reported after allogeneic or autologous HSCT. The usual treatment combines a substantial decrease in, or elimination of, immunosuppressive therapy along with local measures such as surgical excision, cryotherapy or radiation therapy. A 46-year-old woman with chronic myelogenous leukemia who had received an allogeneic HSCT previously from an HLA-identical sibling, presented on day +814 with human herpes virus-8-associated KS involving her left lower extremity. She had been on continuous immunosuppressive therapy since her transplant because of chronic graft-versus-host disease. The intensity of immunosuppressive therapy was decreased once a diagnosis of KS had been established. However, the nodular lesions continued to progress in size and number. Therefore, a course of irradiation was administered to sites of bulk disease on her legs. Furthermore, thalidomide was initiated along with a topical retinoid, alitretinoin 0.1% gel applied twice daily to the nonirradiated lesions. This approach yielded a partial response in both irradiated and nonirradiated lesions over the course of the following 7 months. Both thalidomide and alitretinoin 0.1% gel appear to be beneficial in HSCT-associated KS and exhibit tolerable side effects.

Cytomegalovirus viremia, viruria and disease after autologous peripheral blood stem cell transplantation: no need for surveillance.

A retrospective evaluation of 200 consecutive recipients of autologous peripheral blood stem cell transplantation (PBSCT) was conducted to ascertain the incidence, risk factors, clinical features, complications, and outcome of cytomegalovirus (CMV) infection. A total of 26 patients (13%) developed CMV viremia (n = 5), DNAemia (n = 3), viruria (n = 18) and/or disease (n = 3) at a median of 45 days following stem cell infusion. None of the patients underwent surveillance testing for CMV. A diagnosis was established by culture and polymerase chain reaction of blood, urine or other tissue samples submitted when patients exhibited clinical features suggestive of CMV infection. Cytomegalovirus seropositivity prior to transplantation was the only statistically significant risk factor predicting subsequent identification of CMV (P < 0.001). The symptoms were severe enough in 23 patients to warrant treatment with intravenous ganciclovir. Three patients developed CMV disease; two developed fatal CMV pneumonia and one developed CMV gastritis which responded to antiviral treatment. Clinical signs and symptoms as well as viremia and viruria resolved with (20 patients) and without (three patients) treatment in the remaining individuals. All instances of CMV viremia, DNAemia, viruria and disease occurred within 3 months of stem cell infusion. These results demonstrate that CMV is a common pathogen after autologous PBSCT and may result in fatality in rare instances. Surveillance programs appear to be neither useful nor cost-effective. Diagnostic evaluation should be performed only in patients exhibiting suspicious clinical features and antiviral chemotherapy should be administered for persistent and severe signs and symptoms.

Incidence and outcome of Clostridium difficile infection following autologous peripheral blood stem cell transplantation.

A retrospective evaluation of 200 consecutive recipients of autologous peripheral blood stem cell transplantation (PBSCT) was conducted to ascertain the incidence and outcome of infection with Clostridium difficile. The diagnosis was confirmed in 14 patients with diarrhea (15 episodes) at a median of 33 days after stem cell infusion. Five patients were neutropenic at the time of diagnosis. Every individual had adverse known risk factors such as recent or current use of antibiotic, corticosteroid and antiviral therapy, recent administration of myeloablative chemotherapy and numerous, prolonged periods of hospitalization. Diarrhea, frequently hemorrhagic, was the most common presenting feature along with fever, abdominal cramps and abdominal distention. Diagnosis was established by the stool-cytotoxin test. Response to standard treatment with oral vancomycin or metronidazole was prompt despite the presence of several adverse prognostic features in these patients. There was only one instance of relapse which was also treated successfully. Several transplant-related variables such as age, sex, underlying malignancy, myelo-ablative regimen, duration of neutropenia, and prophylactic use of oral ampicillin underwent statistical analysis but failed to be predictive of C. difficile infection in such a setting. Finally, C. difficile is not uncommon after autologous PBSCT and must be included in the differential diagnosis in any such patient with diarrhea.

Varicella zoster virus infection associated with high-dose chemotherapy and autologous stem-cell rescue.

A retrospective evaluation of 215 consecutive recipients of high-dose chemotherapy (HDC) and autologous stem cell rescue (ASCR) was conducted to ascertain the incidence, temporal course, and outcome of varicella zoster virus (VZV) infection. Herpes zoster was identified in 40 individuals at a median of 69 days following ASCR. Six of these cases occurred at a median of 33 days prior to ASCR but following the initiation of high doses of stem cell mobilization chemotherapy. Twenty-five percent of patients demonstrated cutaneous or systemic dissemination and 32.5% required medical intervention for post-herpetic neuralgia. All except two individuals received antiviral chemotherapy. One patient with active VZV infection died of multiorgan failure 39 days after ASCR. Multivariate analysis of risk factors disclosed the significance of prophylactic acyclovir use in Herpes simplex virus seropositive individuals in reducing the risk of VZV infection. Moreover, the use of busulfan, thiotepa and carboplatin as the conditioning chemotherapy regimen was associated with an increased risk of subsequent VZV infection. The incidence of VZV reactivation after HDC and ASCR is similar to that observed following bone marrow transplantation but has an earlier onset. This may be related to an earlier induction of immunosuppression by stem cell mobilization chemotherapy administered prior to ASCR. We demonstrated a marked reduction in the proliferative and synthetic capacities of peripheral blood mononuclear cells obtained prior to and following stem cell mobilizing chemotherapy. Moreover, greater than 80% of VZV infections occurred within 6 months following ASCR and late cases were seldom observed compared to allogeneic and autologous bone marrow transplantation. The role of antiviral chemoprophylaxis during the period of maximum immunocompromise needs to be studied further in the HDC-ASCR setting.

Regional thrombolysis with urokinase for central venous catheter-related thrombosis in patients undergoing high-dose chemotherapy with autologous blood stem cell rescue.

Fifty-one of 300 patients undergoing high-dose chemotherapy with (n = 245) or without (n = 55) autologous stem cell rescue developed central venous catheter-related thrombosis diagnosed by Doppler sonography or contrast venography. Eighteen of these individuals underwent regional thrombolysis defined as the infusion of urokinase into a superficial vein of the ipsilateral upper extremity in a dose not sufficient to produce systemic fibrinolysis by laboratory criteria. Urokinase was administered at a dose of 75,000-150,000 U/hour for 24 to 96 hours and contrast venography was performed to assess response. All individuals had a partial or complete resolution of clinical signs and symptoms. Fifty percent of patients also achieved a partial radiographic response defined as clot lysis with irregular canalization of the vein. Therapeutic doses of heparin for 5 to 7 days and warfarin for at least 3 months were commenced at the conclusion of urokinase therapy. Twelve catheters were salvaged and utilized subsequently until no longer required. Six catheters were removed because of poor catheter function or rethrombosis. The median interval from diagnosis of the thrombus until extraction of the 12 salvaged catheters was 3 months (range 1-8 months). Only a single patient who developed gastrointestinal bleeding required discontinuation of urokinase. Regional thrombolysis is safe, easy to administer, effective in many instances, less costly than the doses of antifibrinolytic agents required to induce systemic fibrinolysis, and should be considered in patients receiving high-dose chemotherapy with autologous stem cell rescue who develop central venous catheter-related thrombosis.

Acanthamoeba meningoencephalitis following autologous peripheral stem cell transplantation.

Amoebic meningoencephalitis is an unusual complication of bone marrow transplantation. We report a case of Acanthamoeba meningoencephalitis in a patient with non-Hodgkin's lymphoma after autologous stem cell transplantation. Leg weakness, fever and urinary retention developed 69 days following transplantation. The patient then developed fever, generalized tonic clonic seizure, rapid deterioration of mental functions and hypercapneic respiratory failure. Magnetic resonance imaging demonstrated a ring enhancing lesion at the level of the thoracic spines 11 and 12. Examination of the cerebrospinal fluid revealed pleocytosis. Despite empiric therapy with broad-spectrum antimicrobial agents, the patient's condition worsened and she died 11 days following admission. Autopsy findings revealed a subacute meningoencephalitis secondary to Acanthamoeba culbertsoni.

Streptococcus viridans bacteremia following autologous peripheral blood stem cell transplantation.

A retrospective evaluation of 200 consecutive recipients of autologous peripheral blood stem cell transplantation was conducted to ascertain the incidence and outcome of Streptococcus viridans bacteremia as well as to determine the role of prophylactic ampicillin therapy in the peri-transplant setting. Viridans streptococci were isolated from the blood of 35 individuals at a median of 6 days (range 2-8 days) following stem cell infusion. The most common isolates were S. sanguis and S. mitis. All patients received ciprofloxacin orally during the peri-transplant period. Additionally, 79 patients received oral ampicillin prophylactically against gram-positive cocci. Although none of the patients suffered a fatal outcome, three individuals developed respiratory compromise requiring mechanical ventilation. Female sex proved to be the only independent risk factor for viridans streptococcal bacteremia (P=0.04). The shorter duration of neutropenia observed after stem cell transplantation did not impact on the incidence of S. viridans infections. Moreover, the prophylactic use of ampicillin failed to decrease the incidence of viridans sepsis and selected out organisms that were resistant to beta-lactam antibiotics.

An autonomously replicating eukaryotic expression vector with a tetracycline-responsive promoter.

The control elements of the tetracycline-resistance operon encoded in Tn10 of Escherichia coli have previously been utilized by Gossen and Bujard [ Proc. Natl. Acad. Sci. 89 (1992) 5547-5551] to establish an efficient transcription regulatory system in mammalian cells. We describe here a modification of this vector system that encodes all required elements, including a neomycin-resistance gene, on an autonomously replicating episome. This, thereby, allows for improved transfection frequency and episome stability, providing an easily selectable marker gene and a promoter whose activity can be easily modulated to control gene expression.

Busulfan-containing pre-transplant regimens for the treatment of solid tumors.

This study investigated the toxicity and efficacy of busulfan-containing pre-transplant regimens in patients with solid tumors. The majority of these patients were also treated on protocols involving two transplant courses aiming at further reducing tumor burden. Between October 1984 and November 1993, we treated 44 patients with recurrent breast cancer (n = 28), sarcoma (n = 10) or ovarian cancer (n = 6) with one of two busulfan-containing regimens. All patients except two had measurable disease prior to transplantation. Twenty-one patients had not received chemotherapy for metastatic disease. Of the remaining 23 patients treated with standard-dose chemotherapy, 14 had progressive disease. Busulfan 16 mg/kg was paired with cyclophosphamide 200 mg/kg (BuCY) or with etoposide 60 mg/kg (Bu-Vp). The Bu-Vp combination (32 courses) was used as the second preparative regimen in patients who had received thiotepa, carboplatin and cyclophosphamide for their first transplant. The BuCY regimen was used in 16 courses, either for single or for tandem transplant. Bone marrow cells only were used in 17 transplants and peripheral blood progenitor cells, with or without bone marrow, in 31 courses. Treatments were usually well tolerated. Common toxicities included mucositis, skin rash and veno-occlusive disease of the liver (fatal in two). One patient developed generalized seizures during busulfan therapy. Hematologic recovery was significantly accelerated with peripheral progenitor cells and permitted the administration of closely spaced tandem transplants. Two patients receiving sequential transplants with BuCY experienced severe long-term neurologic and pulmonary toxicity. Objective responses were noted in 26 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Streamlined approach to creating yeast artificial chromosome libraries from specialized cell sources.

The study of tumor-specific chromosomal abnormalities has been severely impeded by an inability to link cytogenetic to molecular data. Restriction fragment length polymorphism mapping of any particular chromosomal rearrangement to the resolution limit of genetic methodology generates sets of probes that frequently are still too widely spaced to render the rearrangement breakpoints accessible to molecular isolation. The stable propagation of genomic fragments of up to one million base pairs in size as yeast artificial chromosomes (YACs) represents an important development in this regard. However, existing YAC libraries have been made from karyotypically normal sources making the localization and cloning of specific rearrangement breakpoints much more difficult. As a solution to this problem, we present an improved method for creating YAC libraries that can utilize specialized tumor-derived materials and that can be executed effectively in a small laboratory setting. Procedures that enabled more consistent DNA insert size selection and enhanced yeast transformation frequency were employed to generate a human YAC library from a neuroepithelioma cell line containing a characteristic t(11;22) chromosomal translocation. Approximately 40,000 colonies with an average insert size of 330 kilobase pairs were created. This library was screened with two single-copy probes that bracket the translocation breakpoint. YAC clones ranging from 370 to 550 kilobase pairs that were specific for each single-copy probe were identified. Specialized YAC libraries will make many more tumor-specific chromosomal abnormalities accessible to molecular isolation.

Base sequence damage in DNA from X-irradiated monkey CV-1 cells.

Two kinds of 3'-ends were detected in DNA scission fragments of highly repetitive primate component alpha DNA which were isolated from irradiated monkey CV-1 cells. The fragments' 3'-ends were characterized by 5'-32P-end labelling the DNA, followed by examination in high-resolution polyacrylamide gels under denaturing conditions. Hydrolysis of the labelled fragments' termini with exonuclease III of E. coli or by the 3'-phosphatase activity of T4 polynucleotide kinase generated a third, slowest migrating species in each mobility size class. Reference to mobility size class standards makes it highly probable that the fragment ends generated by X-rays in cells are 3'-phosphoryl and 3'-phosphoglycolate, and that they are converted to slower migrating fragments with 3'-OH ends, similar to results obtained with DNA irradiated in water (Henner et al. 1982, 1983 a, b). Densitometer measurements of gel autoradiograms showed that X-ray induction of DNA fragments with 3'-phosphoryl and 3'-phosphoglycolate ends was dose-dependent over a range 100-900 Gy. In CV-1 cells the frequency of single-strand breaks in alpha DNA was 8.6 x 10(-7) breaks/nt/Gy. The two kinds of ends disappeared in post-radiation incubation with a half-time of 1.6 h. These results provide a new means to study X-ray damage and repair of specific sequences in animal cells.