High-dose weekly intravenous immunoglobulin to prevent infections in patients undergoing autologous bone marrow transplantation or severe myelosuppressive therapy. A study of the American Bone Marrow Transplant Group

Effectiveness of immunoglobulin prophylaxis in reducing clinical complications of hematopoietic stem cell transplantation: a systematic review and meta-analysis

BACKGROUND

Prophylactic immunoglobulin has been used with varying efficacy to reduce complications in hematopoietic stem cell transplant recipients.

STUDY DESIGN AND METHODS

A systematic review and meta-analysis was conducted of randomized controlled trials that assessed clinical outcomes (overall survival, transplant-related mortality, graft-versus-host disease [GVHD], veno-occlusive disease [VOD], interstitial pneumonitis, disease relapse, cytomegalovirus [CMV] infection and disease, non-CMV infection) of immunoglobulin prophylaxis versus placebo in hematopoietic stem cell transplant recipients. MEDLINE, EMBASE, EBM Reviews, and the Cochrane Central Register of Controlled Trials were searched up to June 2017. Quality of included studies and outcomes were evaluated via Risk of Bias assessment and Grading of Recommendations, Assessment, Development and Evaluation criteria, respectively.

RESULTS

Of 899 citations screened, 27 studies (n = 3934) were included. Immunoglobulin prophylaxis had no impact on survival (risk ratio [RR], 0.94; 95% confidence interval [CI], 0.88-1.01; 11 studies, n = 1962) but decreased risk of acute GVHD (RR, 0.78; 95% CI, 0.65-0.94; eight studies, n = 1097) and CMV disease (RR, 0.52; 95% CI, 0.28-0.97; two studies, n = 167). Meta-analysis revealed increased risk of VOD (RR, 3.04; 95% CI, 1.10-8.41; three studies, n = 384) and disease relapse (RR, 1.26; 95% CI, 1.07-1.49; seven studies, n = 1647). Other outcomes were small in sample size or nonsignificant. Results should be interpreted cautiously given the low quality of studies and evidence of outcomes.

CONCLUSION

Immunoglobulin prophylaxis did not have a significant effect on survival. Positive clinical effects were shown for acute GVHD and CMV disease and negative effects against VOD and disease relapse. No studies examined the effect of immunoglobulin treatment in hypogammaglobulinemic patients despite current guidelines, warranting further studies in this population.

Role of Immunoglobulin Therapy to Prevent and Treat Infections

Immunoglobulins have been used widely in medicine for a variety of diseases including infectious diseases. While the main clinical applications of immunoglobulin therapy concern their use as replacement for patients with primary immunodeficiencies, or as treatment for autoimmune and inflammatory disorders, their role in infectious disease is limited largely to viral and toxin neutralization and replacement therapy in patients with immunoglobulin deficiencies. Many aspects of the therapeutic regimen of immunoglobulins even in the established indications remain open. Recently, due to the worldwide surge of immunosuppression caused by AIDS, organ transplantation, cancer, and autoimmune therapies, as well as the emergence of multidrug-resistant bacteria, there has been renewed interest in the use of antibody preparation to prevent infections in high-risk groups.

Knowing the limitations of the current anti-infective armamentarium, approaches that target the host through manipulations to augment the host immune response provide a helpful aid to conventional treatment options. A substantial body of evidence has demonstrated that strategies aiming to support or stimulate immune response could be feasible approaches that would benefit immunocompromised patients. In the present chapter, we present contemporary indications of immunoglobulin administration for therapy and prophylaxis of infections in the immunocompromised population.

Consensus Report by the Pediatric Acute Lung Injury and Sepsis Investigators and Pediatric Blood and Marrow Transplantation Consortium Joint Working Committees on Supportive Care Guidelines for Management of Veno-Occlusive Disease in Children and Adolescents, Part 3: Focus on Cardiorespiratory Dysfunction, Infections, Liver Dysfunction, and Delirium

Some patients with veno-occlusive disease (VOD) have multiorgan dysfunction, and multiple teams are involved in their daily care in the pediatric intensive care unit. Cardiorespiratory dysfunction is critical in these patients, requiring immediate action. The decision of whether to use a noninvasive or an invasive ventilation strategy may be difficult in the setting of mucositis or other comorbidities in patients with VOD. Similarly, monitoring of organ functions may be very challenging in these patients, who may have fulminant hepatic failure with or without hepatic encephalopathy complicated by delirium and/or infections. In this final guideline of our series on supportive care in patients with VOD, we address some of these questions and provide evidence-based recommendations on behalf of the Pediatric Acute Lung Injury and Sepsis Investigators and Pediatric Blood and Marrow Transplantation Consortium Joint Working Committees.

National Institutes of Health Hematopoietic Cell Transplantation Late Effects Initiative: The Immune Dysregulation and Pathobiology Working Group Report

Immune reconstitution after hematopoietic stem cell transplantation (HCT) beyond 1 year is not completely understood. Many transplant recipients who are free of graft-versus-host disease (GVHD) and not receiving any immunosuppression more than 1 year after transplantation seem to be able to mount appropriate immune responses to common pathogens and respond adequately to immunizations. However, 2 large registry studies over the last 2 decades seem to indicate that infection is a significant cause of late mortality in some patients, even in the absence of concomitant GVHD. Research on this topic is particularly challenging for several reasons. First, there are not enough long-term follow-up clinics able to measure even basic immune parameters late after HCT. Second, the correlation between laboratory measurements of immune function and infections is not well known. Third, accurate documentation of infectious episodes is notoriously difficult. Finally, it is unclear what measures can be implemented to improve the immune response in a clinically relevant way. A combination of long-term multicenter prospective studies that collect detailed infectious data and store samples as well as a national or multinational registry of clinically significant infections (eg, vaccine-preventable severe infections, opportunistic infections) could begin to address our knowledge gaps. Obtaining samples for laboratory evaluation of the immune system should be both calendar and eventdriven. Attention to detail and standardization of practices regarding prophylaxis, diagnosis, and definitions of infections would be of paramount importance to obtain clean reliable data. Laboratory studies should specifically address the neogenesis, maturation, and exhaustion of the adaptive immune system and, in particular, how these are influenced by persistent alloreactivity, inflammation, and viral infection. Ideally, some of these long-term prospective studies would collect information on long-term changes in the gut microbiome and their influence on immunity. Regarding enhancement of immune function, prospective measurement of the response to vaccines late after HCT in a variety of clinical settings should be undertaken to better understand the benefits as well as the limitations of immunizations. The role of intravenous immunoglobulin is still not well defined, and studies to address it should be encouraged.

A national survey of screening and management of hypogammaglobulinemia in Canadian transplantation centers

BACKGROUND

Infection remains one of the most common transplant-related causes of death in patients undergoing transplantation. Secondary hypogammaglobulinemia (HGG) as a component of immune suppression and deficiency is associated with both solid organ transplantation (SOT) and hematopoietic cell transplantation (HCT). Available data and clinical experience for the supplementation of immunoglobulin (Ig) in these patients is conflicting, and differing clinical opinion accounts for non-uniform practice in the use of Ig treatment. We aimed to survey lead transplant practitioners for current practice around polyvalent Ig use in post-transplant recipients across Canada.

METHODS

We performed a survey study using short questionnaires to estimate rate of screening of HGG, use of polyvalent Ig, and physician's opinion on Ig treatment and infection prevention. Directors of 24 SOT and 23 HCT centers across Canada were invited to participate in the survey via an electronic mail.

RESULTS

Overall response rate was 63.8%. Twenty percent of SOT programs routinely measured Ig levels pre-transplant compared to 33% of allogeneic (allo-) and 21% of autologous (auto-) HCT programs. Post-transplant Ig levels were measured in 13%, 75%, and 29% in SOT, allo-HCT, and auto-HCT, respectively. The SOT and auto-HCT groups indicated that they do not prescribe Ig therapy (100% and 86%), contrary to the allo-HCT group (42%). Of the respondents in the SOT, allo-HCT, and auto-HCT groups, 60%, 67%, and 36%, respectively, thought infections could be prevented with intravenous immunoglobulins (IVIg). A majority of respondents indicated they would be interested in participating in a randomized controlled trial evaluating the use of IVIg in the SOT and in both HCT groups (100%, 83%, and 57%, respectively).

CONCLUSIONS

Our study shows significant variation in practice between SOT and HCT centers with respect to screening and management of HGG. There is willingness to participate in a randomized controlled trial to address whether Ig treatment reduces infection in post-transplant recipients.

Update on the use of immunoglobulin in human disease: A review of evidence

Human immunoglobulin preparations for intravenous or subcutaneous administration are the cornerstone of treatment in patients with primary immunodeficiency diseases affecting the humoral immune system. Intravenous preparations have a number of important uses in the treatment of other diseases in humans as well, some for which acceptable treatment alternatives do not exist. We provide an update of the evidence-based guideline on immunoglobulin therapy, last published in 2006. Given the potential risks and inherent scarcity of human immunoglobulin, careful consideration of its indications and administration is warranted.

Comparison of prophylactic use of intravenous immunoglobulin versus Pentaglobin® in pediatric patients after hematopoietic stem cell transplantation

There are few studies evaluating the use of IgM-enriched IVIG (Pentaglobin(®) ) in HSCT recipients. This study aimed to compare the efficacy of prophylactic use of IVIG versus prophylactic use of Pentaglobin(®) within the first 100 days after allogeneic HSCT. We performed a prospective, randomized study of the use of prophylactic IVIG versus prophylactic use of Pentaglobin(®) in patients after allogeneic HSCT. The first dose of IVIG or Pentaglobin(®) was given before conditioning regimen and after transplant was given on day +1, +8, +15, and +22. And then, it was given if IgG level was below 400 mg/dL. Twenty-seven patients in IVIG group and 32 patients in Pentaglobin(®) group were included in the study. There were no significant differences in the duration of neutropenia, hospitalization, fever, and in the number of pyrexial episode, septicemia, bacteremia, local infection, CMV infection, acute GVHD, VOD, and adverse events between the IVIG group and Pentaglobin(®) group. Randomized placebo-controlled trials are needed to conclude that utilization of IVIG or Pentaglobin(®) has no beneficial effect in HSCT.

Incidence of infection according to intravenous immunoglobulin use in autologous hematopoietic stem cell transplant recipients with multiple myeloma

BACKGROUND

Although intravenous immunoglobulin (IVIG) is not routinely recommended, many centers still use IVIG during the post-hematopoietic stem cell transplant (HSCT) period.

METHOD

A total of 162 multiple myeloma (MM) patients who underwent autologous (auto-) HSCT between January 2008 and June 2013 were retrospectively reviewed. Primary objective was determination of the impact of IVIG on post-transplant infection, and secondary objectives included identification of overall incidence of infection, type of infection, and risk factors for infection after auto-HSCT in MM patients.

RESULTS

After auto-HSCT, 53 of 162 patients (32.7%) experienced 104 infectious events. Upper respiratory infection was most common (n = 31, 29.8%) and pneumonia (n = 27, 26.0%) and herpes zoster (n = 15, 14.4%) came next. Among the identifiable organisms causing respiratory infection, influenza virus (n = 10) and Pneumococcus (n = 9) were predominant. Incidence of infection was not statistically different according to IVIG use (34.8% in IVIG (-) vs. 31.3% in IVIG (+), P = 0.631). Incidence of infection requiring hospitalization and multiple episodes of infection showed no difference between the groups (P = 0.147, P = 0.156). In a Cox proportional hazard model, none of the factors including age, gender, type of disease, stage, tandem (vs. single) transplantation,and IVIG was prognostic for infectious event after auto-HSCT (P = 0.955, hazard ratio 0.980 with 95% confidence interval 0.481-1.997 for IVIG).

CONCLUSION

In auto-HSCT recipients with MM, incidence of post-transplant infection was not different according to prophylactic IVIG use.

Prophylactic intravenous immunoglobulin during autologous haemopoietic stem cell transplantation for multiple myeloma is not associated with reduced infectious complications

Patients with multiple myeloma undergoing autologous haemopoietic stem cell transplantation (ASCT) are at high risk for infectious complications. Peri-transplant intravenous immunoglobulin (IVIG) has been used with the aim of reducing these risks. Our retrospective, non-randomised study of peri-transplant IVIG use and effect on infectious complications in 266 ASCTs for myeloma from 2000 to 2009 at a major metropolitan referral centre for haematological malignancies found no difference between those receiving peri-transplant IVIG (0.4 g/kg) (n=130) and those who were not (n=110) with regard to bloodstream infections, pneumonia, urinary tract or gastrointestinal infections. When analysed according to pre-transplant therapy (conventional chemotherapy versus novel agents), there was no significant difference in infectious complications between those who did or did not receive peri-transplant IVIG. In conclusion, our study did not show a benefit for the use of peri-transplant IVIG (0.4 g/kg) to reduce infectious complications in a large cohort of patients with myeloma undergoing ASCT. In the absence of data supporting efficacy in this context, there appears to be no benefit in the routine use of IVIG for this purpose.

Evidence for the use of intravenous immunoglobulins--a review of the literature

Intravenous immunoglobulins (IVIg) were first introduced in the middle of the twentieth century for the treatment of primary immunodeficiencies. In 1981, Paul Imbach noticed an improvement of immune-mediated thrombocytopenia, in patients receiving IVIg for immunodeficiencies. This opened a new era for the treatment of autoimmune conditions with IVIg. Since then, IVIg has become an important treatment option in a wide spectrum of diseases, including autoimmune and acute inflammatory conditions, most of them off-label (not included in the US Food and Drug Administration recommendation). A panel of immunologists and internists with experience in IVIg therapy reviewed the medical literature for published data concerning treatment with IVIg. The quality of evidence was assessed, and a summary of the available relevant literature in each disease was given. To our knowledge, this is the first all-inclusive comprehensive review, developed to assist the clinician when considering the use of IVIg in autoimmune diseases, immune deficiencies, and other conditions.

Immunoglobulin prophylaxis in hematopoietic stem cell transplantation: systematic review and meta-analysis

PURPOSE

Because the role of immunoglobulins (IVIG) prophylaxis in patients undergoing hematopoietic stem-cell transplantation (HSCT) has not been established in terms of survival and infection prevention, we conducted a meta-analysis evaluating these issues.

METHODS

Systematic review and meta-analysis of randomized-controlled trials comparing prophylaxis with polyvalent IVIG or cytomegalovirus (CMV)-IVIG and control or another preparation or dose. PUBMED, Cochrane Library, LILACS, and conference proceedings were searched. Two reviewers appraised the quality of trials and extracted data. Relative risks (RRs) with 95% CIs were estimated and pooled.

RESULTS

Thirty trials including 4,223 patients undergoing bone marrow transplantation (BMT) were included. There was no difference in all-cause mortality when polyvalent IVIG or CMV-IVIG was compared to control (RR, 0.99; 95% CI, 0.88 to 1.12; and RR, 0.86; 95% CI, 0.63 to 1.16, respectively). There was no difference in clinically documented infections when polyvalent IVIG was compared with control (RR, 1.00; 95% CI, 0.90 to 1.10; five trials). CMV infections were not significantly reduced with either polyvalent IVIG or CMV-IVIG. Interstitial pneumonitis was reduced with polyvalent IVIG in older studies but not in the more recent ones, nor in studies assessing CMV-IVIG. Polyvalent IVIG increased the risk for veno-occlusive disease (RR, 2.73; (95% CI, 1.11 to 6.71). Graft-versus-host disease was not affected.

CONCLUSION

Because there is no advantage in terms of survival or infection prevention, IVIG does not have a role in HSCT.

Immunoglobulin prophylaxis in hematological malignancies and hematopoietic stem cell transplantation

BACKGROUND

Patients undergoing hematopoietic stem cell transplantation (HSCT) and those with lymphoproliferative disorders (LPD) have a higher incidence of infections due to secondary hypogammaglobulinemia. One approach is the prophylactic administration of intravenous immunoglobulins (IVIG). Randomized controlled trials (RCTs) showed conflicting results in terms of type, schedule, dose and hematological patients benefiting from IVIG. We therefore performed a systematic review and meta-analysis to evaluate the role of IVIG in these patients.

OBJECTIVES

To determine whether prophylaxis with IVIG reduces mortality or affects other outcomes in patients with hematological malignancies.

SEARCH STRATEGY

PubMed (January 1966 to December 2007), CENTRAL (The Cochrane Library, up to 2007, issue 1), LILACS and conference proceedings published between 2002-2007 were searched. The terms "immunoglobulins" or "gammaglobulins" or specific gammaglobulins and similar and the terms "hematologic neoplasms" or "hematologic malignancies" or "transplant" or "autotransplant" or "allotransplant" or "bone marrow transplant" or "peripheral stem cell transplant" and similar were selected. References of all included trials and reviews identified were scanned for additional trials.

SELECTION CRITERIA

All RCTs comparing prophylaxis of IVIG with placebo, no treatment or another immunoglobulin preparation, different administration schedules or doses for patients with hematological malignancies were included. One author screened all abstracts identified through the search strategy and two reviewers independently inspected each reference identified by the search and applied inclusion criteria.

DATA COLLECTION AND ANALYSIS

For each trial, results were expressed as relative risks (RR) with 95% confidence intervals (CI) for dichotomous data and weighted mean differences for continuous data. We conducted meta-analysis, where enough similar trials were available, using the fixed- effects model, unless significant heterogeneity was present. We performed sensitivity analyses to assess the effect of individual methodological quality measures on effect estimates, including allocation generation, concealment and blinding.

MAIN RESULTS

Forty trials were included: thirty included HSCT patients and ten included patients LPD. When polyvalent immunoglobulins or hyperimmune cytomegalovirus (CMV)-IVIG was compared to control for HSCT, there was no difference in all-cause mortality. Polyvalent immunoglobulins significantly reduced the risk for interstitial pneumonitis but increased the risk for veno-occlusive disease and adverse events. In LPD, no benefit in terms of mortality IVIG could be demonstrated but there was a decrease in clinically and microbiologically documented infections.

AUTHORS' CONCLUSIONS

In patients undergoing HSCT, routine prophylaxis with IVIG is not supported. Its use may be considered in LPD patients with hypogammaglobulinemia and recurrent infections, for reduction of clinically documented infections.

Guidelines on the Use of Intravenous Immune Globulin for Hematologic Conditions

Canada's per capita use of intravenous immune globulin (IVIG) grew by approximately 115% between 1998 and 2006, making Canada one of the world's highest per capita users of IVIG. It is believed that most of this growth is attributable to off-label usage. To help ensure IVIG use is in keeping with an evidence-based approach to the practice of medicine, the National Advisory Committee on Blood and Blood Products of Canada (NAC) and Canadian Blood Services convened a panel of national experts to develop an evidence-based practice guideline on the use of IVIG for hematologic conditions. The mandate of the expert panel was to review evidence regarding use of IVIG for 18 hematologic conditions and formulate recommendations on IVIG use for each. A panel of 13 clinical experts and 1 expert in practice guideline development met to review the evidence and reach consensus on the recommendations for the use of IVIG. The primary sources used by the panel were 3 recent evidence-based reviews. Recommendations were based on interpretation of the available evidence and where evidence was lacking, consensus of expert clinical opinion. A draft of the practice guideline was circulated to hematologists in Canada for feedback. The results of this process were reviewed by the expert panel, and modifications to the draft guideline were made where appropriate. This practice guideline will provide the NAC with a basis for making recommendations to provincial and territorial health ministries regarding IVIG use management. Specific recommendations for routine use of IVIG were made for 7 conditions including acquired red cell aplasia; acquired hypogammaglobulinemia (secondary to malignancy); fetal-neonatal alloimmune thrombocytopenia; hemolytic disease of the newborn; HIV-associated thrombocytopenia; idiopathic thrombocytopenic purpura; and posttransfusion purpura. Intravenous immune globulin was not recommended for use, except under certain life-threatening circumstances, for 8 conditions including acquired hemophilia; acquired von Willebrand disease; autoimmune hemolytic anemia; autoimmune neutropenia; hemolytic transfusion reaction; hemolytic transfusion reaction associated with sickle cell disease; hemolytic uremic syndrome/thrombotic thrombocytopenic purpura; and viral-associated hemophagocytic syndrome. Intravenous immune globulin was not recommended for 2 conditions (aplastic anemia and hematopoietic stem cell transplantation) and was contraindicated for 1 condition (heparin-induced thrombocytopenia). For most hematologic conditions reviewed by the expert panel, routine use of IVIG was not recommended. Development and dissemination of evidence-based guidelines may help to facilitate appropriate use of IVIG.

Structure-function studies for in vitro chemical inhibition of Fc? receptor?mediated phagocytosis

BACKGROUND

Previous studies [Transfusion 2005;45:384] showed that certain chemical compounds containing sulfur-reactive groups can inhibit Fcgamma receptor (FcgammaR)-mediated phagocytosis in vitro. These studies, however, did not prove that only sulfur functionality-induced reactivity was efficacious. In an effort to develop a drug-based approach for the future treatment of immune-mediated cytopenias, these earlier findings have now been extended and this chemically induced interference with FcgammaR-mediated phagocytosis of anti-D-coated red cells (RBCs) was examined to assess the optimal structural requirements for the inhibitory effect.

STUDY DESIGN AND METHODS

Chemical compounds were purchased or synthesized and used for the assessment of which chemical moiety(-ies) were required for successful inhibition of in vitro phagocytosis of anti-D-coated RBCs with a monocyte monolayer assay.

RESULTS

Using compounds having similar structures but differences in reactive moieties, it was proved that the only chemical moiety that was required for inhibition of FcgammaR-mediated phagocytosis in vitro was a disulfide bond. It is also shown, however, that a p-nitrophenyl group provides significant enhancement to the inhibitory effect of disulfide-containing compounds. Involvement of carbonyl and hydroxyl functional groups was also able to be ruled out.

CONCLUSION

Our results confirm and extend previous studies that suggested that only those compounds that target free sulfhydryl groups on the monocyte-macrophage are most effective at blocking phagocytosis of antibody-coated RBCs in vitro. It is also shown that p-nitrophenyl substituent groups have an enhancing effect on the efficacy of disulfide bond-containing compounds. These findings should aid in the design of a drug-based approach for the future treatment of immune cytopenias.

Intravenous immunoglobulin: striving for appropriate use

BACKGROUND

Intravenous immunoglobulin (IVIG) is the mainstay therapy in human immune deficiency states characterized by qualitative and quantitative reductions in B cells. In addition, however, there is widespread use of IVIG in a number of other areas, including neuroimmunologic, infectious, dermatologic, hematologic, autoimmune, inflammatory and idiopathic disorders. In many of these cases, there are little objective data to support the use.

METHODS

We performed a review of more than 400 publications in PubMed using the key words 'intravenous immunoglobulin' and excluded publications that focused on immune deficiency, for which the indication for IVIG is already clear.

RESULTS

For a number of off-label indications, there is significant evidence of efficacy and IVIG has become the standard of care for many clinical syndromes other than immune deficiency. In some conditions, however, the data have not been well controlled or randomized and are often limited to case reports that are difficult to interpret. Although the critical shortage of IVIG of the last decade is no longer an issue, IVIG is expensive and not without risk. The use of IVIG should be based not only on clinical data, but also, and especially, on the biological rationale for its use.

CONCLUSIONS

The appropriate use of IVIG is an important issue that is difficult to resolve, and will continue to challenge clinicians based on expense and potentially limited supply, including the intrinsic limitations of donor plasma. The establishment of national and international voluntary registries to report use of IVIG in disorders for which evidence is lacking would be a first step toward facilitating randomized, controlled clinical trials.

Management of sepsis in neutropenia: guidelines of the infectious diseases working party (AGIHO) of the German Society of Hematology and Oncology (DGHO)

These guidelines from the infectious diseases working party (AGIHO) of the German Society of Hematology and Oncology (DGHO) give recommendations for the management of adults with neutropenia and the diagnosis of sepsis. The guidelines are written for clinicians and focus on pathophysiology, diagnosis, and treatment of sepsis. The manuscript contains evidence-based recommendations for the assessment of the quality and strength of the data.

Review: intravenous immunoglobulin therapy and thromboembolic complications

Intravenous immunglobulin (IVIg) is used to treat a number of immune-deficiences and autoimmune diseases. Safety concerns related to a number of reported thromboembolic complications prompted us to review the literature. These complications happened mainly in individuals that had risk factors for thromboembolism, like advanced age, previous thromboembolic diseases, bed-ridden, and in individuals in which high doses or high infusion rates of IVIg were administered. The mechanism responsible for these events seems to be a rise in plasma viscosity that can trigger a thromboembolic event, especially in cases in which there is an underlying circulation impairment. Complications can be minimized by using IVIg only in clear-cut indications, weighting risk versus benefit in patients who are at high risk for thromboembolism and by sticking to carefully monitored slow infusion rates. IVIg for the treatment of autoimmune disorders should be administered as a five-day course of 2 g/kg of body weight. Each daily dose of 400 mg/kg should be given in not less than eight hours.

Profilaxis de las infecciones en el paciente neutropénico

Infections are the main cause of death in neutropenic patients and are related to the degree and duration of neutropenia, the underlying disease, and the treatments received. To reduce the number of these infections, prophylactic strategies have been proposed. These strategies aim to prevent adquisition through contact, inhalation, or the gastrointestinal tract. Intestinal decontamination through fluoroquinolones has reduced Gram-negative infections but this strategy should not be used indiscriminately and should be reserved for high risk patients. Fluconazole as antifungal prophylaxis reduces mortality but does not modify the incidence of invasive aspergillosis. Cytomegalovirus infection should be prevented in patients with negative serology; in high risk patients with positive serology, monitoring and preemptive treatment with ganciclovir or foscarnet is recommended. Hematopoietic growth factors reduce the duration of neutropenia and could reduce mortality from infection.

Indications thérapeutiques des immunoglobulines intraveineuses

KEY POINTS

Intravenous immunoglobulins (IVIg) are preparations of normal human IgG obtained from large pools of healthy blood donors. IVIg can be used at low doses to treat patients with primary or secondary immune deficiencies and at high doses as an immunomodulatory agent in many autoimmune and systemic inflammatory diseases, especially hematologic and neurologic diseases. Its mechanisms of action are multiple, complex, and not yet well elucidated. Adverse effects are only rarely associated with IVIg. They are well tolerated, and the risk of transmission of infectious agents appears only theoretical.

Platelet transfusion containing ABO-incompatible plasma and hepatic veno-occlusive disease after hematopoietic transplantation in young children

BACKGROUND

Hepatic veno-occlusive disease is a major limiting factor of high-dose chemotherapy in children. The cells lining the hepatic vascular endothelium express blood group A and/or B antigens according to the patient's blood group. We designed a study evaluating the impact of platelet concentrates containing ABO-incompatible plasma transfused to young children with a high risk of hepatic veno-occlusive disease.

METHODS

In all, 186 consecutive children (median age: 4 years, range: 0.75-17 years), treated with high-dose chemotherapy containing busulfan followed by hematopoietic stem cell transplantation for neuroblastoma (n=112) or brain tumor (n=74) between 1988 and 1998, were investigated. The main endpoint was the occurrence of hepatic veno-occlusive disease. Multivariate analysis was performed using a Cox's regression model with transfusion of platelet concentrates containing ABO-incompatible plasma as a time-dependent covariate.

RESULTS

We found that 73 out of 186 (39%) children developed hepatic veno-occlusive disease after transplantation. Multivariate analysis demonstrated that two factors significantly increased the risk of hepatic veno-occlusive disease occurrence: transfusion of platelet concentrates containing ABO-incompatible plasma (P=0.003) and use of melphalan in the conditioning regimen (P=0.006). Conversely, the number of platelet concentrates transfusions per week, child's age, weight, sex, and use of cyclophosphamide in the conditioning regimen had no effect.

CONCLUSIONS

Transfusion of platelet concentrates containing ABO-incompatible plasma increases the risk of hepatic veno-occlusive disease in young children treated with a busulfan-containing regimen. Binding of A and/or B antigens expressed on the surface of hepatic endothelial cells may promote this complication. Transfusion of platelet concentrates containing ABO-incompatible plasma should be avoided in these children.

Antimicrobial prophylaxis in allogeneic bone marrow transplantation. Guidelines of the Infectious Diseases Working Party (AGIHO) of the German Society of Haematology and Oncology

Patients undergoing allogeneic stem cell transplantation are at high risk for infection with a variety of pathogens during different phases of the procedure. Bacteria and fungi predominate the first phase until engraftment. During the second phase, from engraftment to about day 100, major infectious problems are caused by fungi and cytomegalovirus. Both pathogens remain important under continued immunosuppression, however, in the late post-transplantation period infections with encapsulated bacteria may become a problem. In this review the Infectious Diseases Working Party of the DGHO gives recommendations for prophylaxis of infections under allogeneic stem cell transplantation with drugs and other measures. The aim of the group was to do this on an evidence-based-medicine rating, if possible.

Immune restoration following hematopoietic stem cell transplantation: an evolving target

Hematopoietic stem cell transplantation (HSCT) is the definitive cure for many malignant and nonmalignant diseases. However, delays in immune reconstitution (IR) following HSCT significantly limit the success of transplantation and increase the risk for infection and disease relapse in the transplant recipient. Therefore, ways to measure and to manipulate immune recovery following HSCT are emerging and their success depends directly upon an enhanced understanding for the underlying mechanisms responsible for reconstituted immunity and hematopoiesis. Recent discoveries in the activation, function, and regulation of dendritic cell (DC), natural killer (NK) cell, and T-lymphocyte subtypes have been critical in developing immunotherapies used to prevent graft-versus-host disease and to enhance graft-versus-leukemia. For example, regulatory T cells that induce tolerance and NK receptor-tumor ligand disparities that result in tumor lysis are being used to minimize GVHD and tumor burden, respectively. Furthermore, expansion and modulation of immune effector cells are being used to augment hematopoietic and immune recovery and to decrease transplant-related toxicity in the transplant recipient. Specifically, DC expansion and incorporation into antitumor and anti-microbial vaccines is fast approaching application into clinical trials. This paper will review our current understanding for IR following HSCT and the novel ways in which to restore immune function and decrease transplant-related toxicity in the transplant recipient.

A synergistic effect of albumin and fibrinogen on immunoglobulin-induced red blood cell aggregation

Therapeutic administration of immunoglobulins (Ig) has the potential to precipitate thrombotic events. This phenomenon may be explained by red blood cell (RBC) aggregation, which can be potentiated by Ig. The contribution of plasma albumin and fibrinogen to Ig-induced RBC aggregation is unclear. We examined RBC aggregation in three settings: 1) patients receiving therapeutic infusions of Ig; 2) patients receiving plasma supplemented in vitro with Ig; and 3) patients receiving RBC suspensions in standard buffer with varying concentrations of albumin, Ig, and fibrinogen. Ig infusion augmented aggregation of RBCs from patients with normal or high plasma levels of albumin but decreased aggregation in those with lower plasma albumin concentrations. In vitro, RBC aggregation was significantly increased only when all three components, fibrinogen, albumin, and Ig, were present at or above normal concentrations in the suspension but was unaffected when any one of the components was absent from the suspension. Our results suggest a three-way interaction among fibrinogen, Ig, and albumin that synergistically induces RBC aggregation in plasma. Understanding these interactions may help predict clinically important phenomena related to RBC aggregation, such as thrombotic complications of Ig infusion.

Incidence, risk factors, and mortality from pneumonia developing late after hematopoietic stem cell transplantation

The incidence, etiology, outcome, and risk factors for developing pneumonia late after hematopoietic stem cell transplantation (SCT) were investigated in 1359 patients transplanted in Seattle. A total of 341 patients (25% of the cohort) developed at least one pneumonic episode. No microbial or tissue diagnosis (ie clinical pneumonia) was established in 197 patients (58% of first pneumonia cases). Among the remaining 144 patients, established etiologies included 33 viral (10%), 31 bacterial (9%), 25 idiopathic pneumonia syndrome (IPS, 7%), 20 multiple organisms (6%), 19 fungal (6%), and 16 Pneumocystis carinii pneumonia (PCP) (5%). The overall cumulative incidence of first pneumonia at 4 years after discharge home was 31%. The cumulative incidences of pneumonia according to donor type at 1 and 4 years after discharge home were 13 and 18% (autologous/syngeneic), 22 and 34% (HLA-matched related), and 26 and 39% (mismatched related/unrelated), respectively. Multivariate analysis of factors associated with development of late pneumonia after allografting were increasing patient age (RR 0.5 for <20 years, 1.2 for >40 years, P=0.009), donor HLA-mismatch (RR 1.6 for unrelated/mismatched related, P=0.01), and chronic graft-versus-host disease (GVHD; RR 1.5, P=0.007). Our data suggest that extension of PCP prophylaxis may be beneficial in high-risk autograft recipients. Further study of long-term anti-infective prophylaxis based on patient risk factors after SCT appear warranted.

Intravenous immunoglobulins in infectious diseases: where do we stand?

Intravenous immunoglobulins (IVIg) are therapeutic preparations of normal human IgG that have been used for more than 20 years for substitutive therapy in patients with primary antibody deficiencies. Recent studies pointed out the need to obtain normal residual levels of IgG (i.e. 8 g/L) in order to reduce the number and severity of bacterial infections in these patients. The IVIg are also prescribed for the substitutive therapy of secondary immunodeficiencies such as chronic lymphoid leukemia and multiple myeloma with hypogammaglobulinemia and severe and/or recurrent infections, and human immunodeficiency virus (HIV)-infected children with recurrent bacterial infections before the era of highly active antiretroviral agents. However, in the latter situation, no recent study has evaluated IVIg therapy in acquired immunodeficiency syndrome (AIDS) children receiving highly active antiretroviral agents (HAART), and the use of IVIg must probably be restricted to the currently rare clinical situation in Western Europe of children with AIDS who develop recurrent infections despite the administration of HAART and prophylactic cotrimoxazole. IVIg have also been reported to prevent infections, interstitial pneumonia and graft-vs. host disease during the first 90 days post-transplant in allogeneic bone-marrow transplant recipients. However, this result was not confirmed by two recent studies and IVIg therapy should probably only be proposed for a subgroup of bone-marrow allografted patients such as those with hypogammaglobulinemia and sepsis. With the exception of erythrovirus B19 infection with erythroblastopenia, no clear benefit of IVIg therapy has been reported for the curative management of other infectious diseases.

Back to the future: antibody-based strategies for the treatment of infectious diseases

Before antibiotics, sera from immune animals and humans were used to treat a variety of infectious diseases, often with successful results. After the discovery of antimicrobial agents, serum therapy for bacterial infections was rapidly forsaken. In the last two decades, problems with treatment of newly emerged, re-emerged, or persistent infectious diseases necessitated researchers to develop new and/or improved antibody-based therapeutic approaches. This article reviews some information on the use of antibodies for the treatment of infectious diseases, with special reference to the most seminal discoveries and current advances as well as available treatment approaches in this field.

Preventing opportunistic infections after hematopoietic stem cell transplantation: the Centers for Disease Control and Prevention, Infectious Diseases Society of America, and American Society for Blood and Marrow Transplantation Practice Guidelines and beyond

This review presents evidence-based guidelines for the prevention of infection after blood and marrow transplantation. Recommendations apply to all myeloablative transplants regardless of recipient (adult or child), type (allogeneic or autologous) or source (peripheral blood, marrow or cord blood) of transplant. In Section I, Dr. Dykewicz describes the methods used to rate the strength and quality of published evidence supporting these recommendations and details the two dozen scholarly societies and federal agencies involved in the genesis and review of the guidelines. In Section II, Dr. Longworth presents recommendations for hospital infection control. Hand hygiene, room ventilation, health care worker and visitor policies are detailed along with guidelines for control of specific nosocomial and community-acquired pathogens. In Section III, Dr. Boeckh details effective practices to prevent viral diseases. Leukocyte-depleted blood is recommended for cytomegalovirus (CMV) seronegative allografts, while ganciclovir given as prophylaxis or preemptive therapy based on pp65 antigenemia or DNA assays is advised for individuals at risk for CMV. Guidelines for preventing varicella-zoster virus (VZV), herpes simplex virus (HSV) and community respiratory virus infections are also presented. In Section IV, Drs. Baden and Rubin review means to prevent invasive fungal infections. Hospital design and policy can reduce exposure to air contaminated with fungal spores and fluconazole prophylaxis at 400 mg/day reduces invasive yeast infection. In Section V, Dr. Sepkowitz details effective clinical practices to reduce or prevent bacterial or protozoal disease after transplantation. In Section VI, Dr. Sullivan reviews vaccine-preventable infections and guidelines for active and passive immunizations for stem cell transplant recipients, family members and health care workers.

Determinants of the efficacy of prophylactic granulocyte transfusions: a meta-analysis

BACKGROUND

Cytokines that improve granulocyte collection yields have recently become available, and may lead to a new series of trials of granulocyte transfusion (GTX) therapy. We conducted a meta-analysis of studies of prophylactic GTX in order to identify the determinants of efficacy of this intervention, and to assist in the design of future trials of GTX for the treatment of patients with overwhelming infection.

METHODS

Randomized controlled trials of the efficacy of prophylactic GTX published in English in 1970-1995 were retrieved, and eight studies were eligible for analysis. Summary relative odds (RR) of bacterial or fungal infection, death, or death from infection in transfused patients vs. controls were computed for patient subsets defined on the basis of dose of granulocytes transfused, assessment of leukocyte compatibility, duration of neutropenia, and infection rate of controls. The random-effects method was used for all analyses.

RESULTS

Assessment of leukocyte compatibility prior to the transfusion, dose of granulocytes transfused, and duration of neutropenia in enrolled patients could account, respectively, for the variation in findings across published reports in terms of all three, two, and one of the outcome measures studied. Transfusion of adequate doses of compatible leukocytes significantly reduced the relative risk (RR) of infection, death, and death from infection in transfused patients vs. controls (RR = 0.075, RR = 0.224, and RR = 0.168, respectively; P < 0.05).

CONCLUSION

Two necessary elements in the design of future trials of therapeutic GTX should be the transfusion of high doses of granulocytes and the provision of leukocytes that are crossmatch-compatible with the recipient's serum.

Deep venous thrombosis of the arm after intravenous immunoglobulin infusion: case report and literature review of intravenous immunoglobulin-related thrombotic complications

Thrombosis resulting from intravenous immunoglobulin infusion is a relatively unknown complication. We describe a patient who developed deep venous thrombosis of her left arm shortly after intravenous immunoglobulin administration. In addition, we review the thrombotic incidences reported in the literature and the possible association with hepatic veno-occlusive disease after bone marrow transplantation. Measures that can potentially prevent this complication are discussed.

Infections in recipients of blood and marrow transplantation

The approach to infections in blood and marrow transplant (BMT) recipients involves an understanding of clinical infection syndromes and the natural history of individual infections, taken in the context of patterns of immunosuppression after transplantation and mechanisms underlying immune system reconstitution over time. The conditioning regimen used to prepare the host is a major determinant of host tissue injury and may lead to mucositis or diarrhea, facilitating transmucosal origin of bloodstream infections. Infectious risk also differs between autologous and allogeneic grafts as a consequence of ongoing immunosuppression from graft-versus-host disease and its therapy. Post-transplant complications may mimic infectious processes, and multiple infections may occur in one patient at the same time. Thus, the BMT patient with suspected infection should be evaluated in the context of pretransplant exposure history (infectious disease serologies), conditioning regimen, available culture data from nonsterile mucosal surfaces, previous and recent infections, contemporary transplant complications, and the current degree and duration of neutropenia, cellular immunodeficiency, and hypogammaglobulinemia.

Current antiviral strategies for controlling cytomegalovirus in hematopoietic stem cell transplant recipients: prevention and therapy

Cytomegalovirus (CMV) remains a cause of significant morbidity and mortality after hematopoietic stem cell transplantation (HSCT). Ganciclovir prophylaxis, or preemptive treatment based on detection of antigenemia or CMV DNA by PCR, effectively prevents CMV disease during the first 100 days after transplant in allograft recipients. In recipients of T-cell depleted transplant or if severe acute graft-versus-host disease is present, ganciclovir prophylaxis or preemptive treatment should be started with an induction course of ganciclovir (5 mg/kg BID) and given at least 5 days per week and continued until day 100 after transplant. Although prevention of CMV disease before day 100 is highly effective, there is a continued risk of late-onset CMV disease after day 100. In CMV-seropositive recipients, the incidence of late CMV disease may be as high as 17%. Strategies to prevent late CMV infection and disease are needed. In seronegative recipients, seronegative or leukocyte-reduced blood products are effective in preventing acquisition of CMV through blood products. Controversy exists about the optimal strategy of preventing CMV disease in seropositive autologous HSCT recipients. The outcome of CMV pneumonia remains poor despite treatment with ganciclovir in combination with CMV hyperimmune globulin or intravenous immunoglobulin. Owing to continued clinical significance of CMV in the HSCT setting, new and more effective anti-CMV drugs with improved pharmacokinetic properties are urgently needed.

Preventing opportunistic infections in bone marrow transplant recipients

In 1996, a Center for Disease Control and Prevention (CDC)-sponsored working group began developing guidelines for preventing opportunistic infections (OIs) in bone marrow transplant (BMT) recipients. The purposes of the guidelines are to: a) summarize current data regarding the epidemiology of OIs in BMT recipients; b) produce an evidence-based statement of recommended strategies for preventing OIs in BMT recipients; c) decrease the incidence, morbidity, and mortality of OIs in BMT recipients; and d) define directions for future OI prevention research. Each recommendation is given two ratings: one indicating the strength of the recommendation, and another indicating the strength of evidence supporting the recommendation. The target audience for the guidelines includes transplant and infectious disease physicians and BMT unit and clinic staff. The BMT OI guidelines include sections on viral, bacterial, fungal, protozoal, and helminth infections, immunization, infection control, and blood and stem cell safety. The disease-specific sections address preventing exposure and disease among both adult and pediatric recipients of allogeneic and autologous BMTs. The immunization section addresses: a) immunization of BMT recipients, their household contacts, and health care workers; b) travel immunizations for BMT recipients; and c) passive immunization with immune globulin products. The infection control sections address room ventilation, isolation and barrier precautions, and prevention of nosocomial and other infections (e.g. infections acquired from visitors, plants, food, pets, construction sites, etc.). The blood safety section contains recommendations on preventing transmission of infections to BMT recipients from infected donated cells. After the guidelines are made available for public comment, they will be finalized and published in the Morbidity and Mortality Weekly Report and placed on the CDC web site.

[Febrile neutropenia: practical aspects]

BACKGROUND

Infections are a major cause of mortality in neutropenic patients. They require long hospital stays and highly expensive therapeutic measures. In this review we discuss the practical and pharmaco-economic aspects of the management of febrile neutropenia.

PREVENTION AND THERAPY

Prevention of fever of unknown origin (FUO) demands hygienic and antimicrobiotic measures. First-line antibiotic therapy consists of an aminoglycoside combined with an ureidopenicillin or a 3rd-generation cephalosporin. Double beta-lactam antibiotic combinations are equally effective and less toxic, but more expensive. Monotherapy with carbapenems, ceftazidime, or cefepime appear to offer comparable efficacy. Lung infiltrates require immediate treatment with amphotericin B. If the initial therapeutic regime fails, a carbapenem plus a glycopeptide antibiotic and a parenteral antimycotic drug should be applied after 3 to 4 days. The prophylactic or interventional administration of hematopoietic growth factors is only indicated in special high-risk situations.

CONCLUSIONS

Using the described therapeutic procedure, the response rate exceeds 90%. Consistent, step-wise escalating administration of antibiotics is essential. More evaluation is needed to determine whether selected patients with febrile neutropenia can be treated on an outpatient basis.

Intravenous immunoglobulin treatment in hematological diseases

In the last decade large amounts of intravenous immunoglobulin (i.v.Ig) have been used worldwide. Doubts exist as to whether this increased use is paralleled by a comparable growth of reliable data on the therapeutic effectiveness of i.v.Ig. We performed a literature search using MEDLINE from January 1981 to January 1997 and analysed articles on the use of i.v.Ig in hematological disorders and searched for published guidelines. For most hematological disorders, evidence to use i.v.Ig as first line therapy is not very strong. For many disorders no controlled trials have been performed. In published guidelines, i.v.Ig is only recommended, with a few exceptions, when other treatments have failed or are contraindicated. Therefore the increase of consumption of i.v.Ig can not be explained by an increase in established indications in hematology.

Allogeneic bone marrow transplantation for hematological malignancies--controversies and recent advances

Today more than 80000 allogeneic bone marrow transplantations (BMT) have been performed worldwide. The major indications are hematological malignancies such as acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), chronic myeloid leukemia (CML) and myelodysplastic syndromes. Unrelated donors are increasingly used and there are around 4 million volunteer donors available in different registers, the largest being the National Marrow Donor Program. Molecular typing has improved the typing technique which has resulted in a decreased risk of graft-versus-host disease (GVHD), lower transplant-related mortality (TRM) and improved leukemia-free survival (LFS). Using HLA-identical siblings, patients with AML in first complete remission (1 CR) and high-risk ALL in 1 CR are clear indications for BMT. However, if an HLA-identical sibling is not available, it is not known today if an unrelated bone marrow or autografting is the best option for all patients with acute leukemia in 1 CR. Because BMT is the only curable treatment for CML, a search for an unrelated donor should start as soon as it is evident that an HLA-identical sibling is not available. BMT within a year from diagnosis is of major importance for outcome. Allogeneic peripheral blood progenitor cells (PBPC) have been used as an alternative to bone marrow. Preliminary studies indicate a faster engraftment, but prospective randomized trials are necessary to establish the role of allogeneic PBPC. Umbilical cord blood has also been used as a source of allogeneic hematopoietic stem cells. Using cord blood from HLA-identical siblings, engraftment seems to be delayed, but the probability of GVHD is low. Preliminary data using unrelated cord blood cells are encouraging. GVHD has an important antileukemic effect. Recently, a graft-versus-myeloma and a graft-versus-breast-cancer effect has been demonstrated. In patients who relapse after BMT, donor lymphocytes can induce remission, especially in patients with CML. With molecular techniques it is possible to detect relapse at an early stage, so called minimal residual disease. Liposomal amphotericin B has few side-effects and decreased the death rate by invasive fungal infection in BMT recipients. Early diagnosis and treatment of cytomegalovirus (CMV) infection with new antiviral drugs have dramatically reduced the incidence and mortality in CMV disease. Cyclosporine combined with methotrexate is today the most widely used immunosuppressive regimen and has decreased GVHD and improved survival. However, several new immunosuppressive drugs need to be explored in clinical BMT. Immune modulation by for instance cytokines and cytokine inhibititors is a new exciting development.

Human intravenous immunoglobulin in primary and secondary antibody deficiencies

IVIG is of value in patients with primary and secondary antibody deficiencies. High dose IVIG therapy is usually the treatment of choice for patients with primary antibody deficiency disease. Sufficient IVIG should be given to maintain IgG trough levels of > 500 mg/dl; this usually requires a dose of 400 to 500 mg/kg/month. Adverse side effects to IVIG has been described; the two most common serious side effects are hepatitis C and aseptic meningitis. New procedures to inactivate hepatitis C (and other viruses) are now in place. Aseptic meningitis is usually associated with high IVIG doses given rapidly to patients with autoimmune and inflammatory disease; its cause is not known. Subcutaneous infusions of IG or IVIG at weekly intervals has been shown to be clinically efficacious, well-tolerated and a less expensive alternative to monthly IVIG infusions. IVIG has been used with encouraging results in selected pediatric patients with HIV infection. The benefit is primarily in patients with CD4 counts > 200 cells/mm2 who receive no P. carinii pneumonia prophylaxis. IVIG may also be of value in preventing or ameliorating infection in other secondary antibody deficiencies including patients with malignancies; patients with protein-losing enteropathy and nephrotic syndrome; severely ill care patients with shock, trauma or surgery; premature infants and patients undergoing transplantation procedures; and severely burned patients. Guidelines for selecting patients for IVIG are offered.

Comparison of early IgM-enriched immunoglobulin vs polyvalent IgG administration in score-identified postcardiac surgical patients at high risk for sepsis

STUDY OBJECTIVE

To address the relevance of the IgM component in polyvalent immunoglobulins in sepsis treatment by comparison of the clinical course under polyvalent IgG vs IgGMA therapy in postcardiac surgical patients at high risk for sepsis and to reassess the prognostic validity of sequential changes in acute physiology and chronic health evaluation (APACHE II) scores during treatment.

DESIGN

Prospective, randomized clinical trial.

SETTING

Cardiac surgical ICU in a university hospital.

PATIENTS

Among 870 consecutive patients after elective open-heart surgery, 29 (3.3%) met the previously validated high-risk criterion (APACHE II score > or = 24 on the first postoperative day) with a mean APACHE II score-predicted mortality risk of 63%.

INTERVENTIONS

In addition to standard therapy, 27 of these patients were randomized to receive commercially available IV IgG (Polyglobin N, n = 14, total dosage: 18 mL/kg) or IgGMA (Pentaglobin, n = 13, total dosage: 15 mL/kg).

MEASUREMENTS AND RESULTS

The two groups were comparable in baseline disease severity and concurrent therapy. The extent of score-quantified improvement in disease severity during treatment was similar in both groups (mean fall in APACHE II scores within 4 days; IgG, -6.9; IgGMA, -5.2), as were score-defined improvement rates (rate of patients with score decrease > or = 7 within 4 days: IgG, 57%; IgGMA, 54%) and in-hospital mortality (IgG, 29%; IgGMA, 31%) (all p = NS). There was a strong association between the decrease over time in APACHE II scores during therapy and prognosis (mortality rates in patients with vs without score-assessed improvement: 0% vs 67%, p = 0.0002).

CONCLUSIONS

IgG and IgGMA were associated with a comparable improvement in disease severity in score-identified postcardiac surgical patients at high risk for sepsis. Given the design as an efficacy rather than an equivalence study, this hypothesis derived from our results needs independent validation in larger trials. Sequential APACHE II score changes were reconfirmed as a prognostically valid quantitative measure of disease progress during sepsis therapy.

Use of intravenous immunoglobulin to prevent or treat infections in persons with immune deficiency

Intravenous immunoglobulin (IVIG) concentrates were originally developed as replacement therapy for individuals with primary deficiencies of the immune system. However, in various well-designed, controlled clinical trials, the ability of IVIG to prevent and possibly treat infections in patients with secondary immune deficiencies has also been considered. In this review, we briefly consider these different applications and suggest whether the data are sufficient to employ IVIG in these clinical settings.

Cytomegalovirus prophylaxis and treatment following bone marrow transplantation

OBJECTIVE

To provide an overview of the role of cytomegalovirus (CMV) in the bone marrow transplant (BMT) population and update the current methods of prevention and treatment of CMV infection and disease, with emphasis on CMV interstitial pneumonia (CMV-IP).

DATA SOURCES

The current medical literature, including abstracts presented at recent national and international meetings, is reviewed. References were identified by searching the MEDLINE database from January 1988 through June 1994. The reference lists of the published studies and reviews obtained from the initial literature search were reviewed as well.

STUDY SELECTION

Data regarding the epidemiology of CMV, the risk factor associated with CMV infection and disease, as well as data on the prevention and the treatment of CMV infection and disease in the BMT population are cited. Specific attention was focused on randomized, placebo-controlled studies pertaining to the prevention of CMV infection and disease in CMV-immunoglobulin G positive recipients undergoing allogeneic BMT. Information from nonrandomized, placebo-controlled studies was included in the absence of stronger data.

DATA EXTRACTION

Information contributing to CMV in the BMT population was reviewed. Data supporting and disputing specific preventive and treatment modalities are presented.

DATA SYNTHESIS

The incidence of CMV seropositivity in the general population is high and while BMT becomes a widely accepted treatment modality, CMV reactivation and subsequent disease, especially CMV-IP, becomes a significant prognostic factor of morbidity and mortality. Even though antiviral agents such as ganciclovir and foscarnet can inhibit the viral replication in vivo, they have not been able to treat CMV-IP effectively. It has been suggested that CMV-IP is an immunopathologic process that can cause irreversible damage, hence, the low efficacy of antiviral therapy and the associated high mortality. Immunomodulating agents such as intravenous immune globulin and cytomegalovirus hyperimmune globulin can increase the efficacy of antivirals in the treatment of CMV-IP. This further supports the postulated immunopathologic process of this disease. The lack of understanding of the pathophysiology of the disease compromised the efforts of treatment and led to the development of preventive interventions with antiviral and immunomodulatory regimens that resulted in a significantly lower incidence of infection and disease. As a result of current data, the Eastern Cooperative Oncology Group has published guidelines for the prevention and treatment of CMV infection and disease.

CONCLUSIONS

The prognosis of CMV disease in the BMT recipients has improved as a result of a wide variety of modifications in the management of BMT recipients. These include an increased understanding of the risk factors associated with CMV infection, routine screening for CMV replication and excretion, and more effective prophylactic regimens. Still, more than half of the patients who develop pneumonia will die, indicating that more studies are needed to increase the understanding of the pathophysiology and refine the preventive and therapeutic regimens against CMV.

Host immunologic augmentation for the control of infection

The emergence of resistance to pharmacologic antimicrobial agents and the desire to increase chemotherapy dose-intensity have necessitated the search for alternative means to control infectious disease. Enhancement of host immunity against infection has been permitted through the use of hematopoietic growth factors, which can shorten the duration of neutropenia and reduce the risk for bacterial and fungal infections. Hematopoietic growth factor-mobilized hematopoietic stem cells have also proven to be highly efficacious in permitting high-dose chemotherapy. Interferons, immunoregulatory cytokines, immune globulins, and immune lymphocytes also hold promise to enhance host immunity and reduce susceptibility for serious infectious morbidity.

Antibody-based therapies for emerging infectious diseases

In the 19th century, it was discovered that immune sera were useful in treating infectious diseases. Serum therapy was largely abandoned in the 1940s because of the toxicity associated with the administration of heterologous sera and the introduction of effective antimicrobial chemotherapy. Recent advances in the technology of monoclonal antibody production provide the means to generate human antibody reagents and reintroduce antibody therapies, while avoiding the toxicities associated with serum therapy. Because of the versatility of antibodies, antibody-based therapies could, in theory, be developed against any existing pathogen. The advantages of antibody-based therapies include versatility, low toxicity, pathogen specificity, enhancement of immune function, and favorable pharmacokinetics; the disadvantages include high cost, limited usefulness against mixed infections, and the need for early and precise microbiologic diagnosis. The potential of antibodies as antiinfective agents has not been fully tapped. Antibody-based therapies constitute a potentially useful option against newly emergent pathogens.