Intravenous anti-D immune globulin-induced intravascular hemolysis in Epstein-Barr virus-related thrombocytopenia

Severe thrombocytopenia and recurrent epistaxis associated with primary Epstein-Barr virus infection

Infectious mononucleosis, caused by the Epstein-Barr virus (EBV), generally follows a benign, yet protracted course, with the majority of symptoms being systemic somatic symptoms. Rarely, the clinical picture can be complicated by more acute severe haemotological sequelae of the disease, requiring hospitalisation and causing diagnostic uncertainty, particularly when distinguishing between a viral illness and a lymphoproliferative disorder. We describe the case of a young male patient who presented with headache, recurrent epistaxis and severe thrombocytopenia.

Acute renal failure in a child with thrombocytopenic purpura caused by acute Epstein-Barr virus infection after treatment with anti-D immunoglobulin

Immune thrombocytopenia (ITP) in children is usually a benign, self-limiting disorder. An acute Epstein-Barr virus (EBV) infection usually causes atypical lymphocytosis and mild decrease in platelets. Severe thrombocytopenia is an extremely rare complication. Anti-D immunoglobulin has been used for treatment of ITP in Rh(D)-positive nonsplenectomized patients. Severe hemolysis and acute renal failure are extremely rare complications that may be aggravated by the presence of an acute EBV infection. It is believed that anti-D immunoglobulin triggers an unusual virus-induced immune response causing hemolysis. We present a 4-year-old girl with ITP caused by an acute EBV infection that developed acute kidney injury following treatment with anti-D immunoglobulin. The patient recovered completely from thrombocytopenia and renal dysfunction. Intravascular hemolysis and acute kidney injury are consistent with anti-D immunoglobulin mechanism of action. Pediatric patients treated with anti-D immunoglobulin for ITP should be closely monitored for signs and symptoms of hemolysis that may be aggravated by the presence of EBV infection leading to impaired renal function.

RhIG for the treatment of immune thrombocytopenia: consensus and controversy (CME)

Anti-D immune globulin (RhIG) is a front-line option in North America for the treatment of immune thrombocytopenia (ITP) in children and adults. Recently, addition of a Food and Drug Administration-mandated black box warning highlighted the risks of intravascular hemolysis, renal failure, and disseminated intravascular coagulation after anti-D infusion, prompting concern within the medical community regarding its use. A working group convened in response to this warning to prepare a consensus document regarding the safety of RhIG because there has been no increased incidence of adverse events since the initial discovery of these reactions many years ago. The efficacy of anti-D is well documented and only briefly reviewed. The estimated incidence and proposed mechanisms for the rare, major treatment-related complications are discussed, and signal detection data associated with heightened risk of acute hemolytic reactions are presented. The importance of considering host factors, given the rarity of severe reactions, is emphasized. Safety profiles of parallel treatment options are reviewed. The working group consensus is that RhIG has comparable safety and efficacy to other front-line agents for the treatment of children and adults with ITP. Safety may be further improved by careful patient selection.

Subcutaneous anti-D globulin application is a safe treatment option of immune thrombocytopenia in children

Subcutaneous (sc) administration of anti-D seems to offer the same efficacy as intravenous administration but with less side effects. Here we report our experience with sc anti-D for pediatric immune thrombocytopenia (ITP). A total of 12 children with a median age of 11.2 years had been treated by sc anti-D. They received a median of 2 sc anti-D applications (range 1-31) with a dosage of 250-375 IE/kg body weight. Only in one out of a total of 102 single applications, a minimal and self-limited side effect (chills) had been observed. The mean platelet count was almost doubled after sc anti-D (p < 0.0001). After a median follow-up of 11.4 months, all patients are alive without major bleeding and stay well. We conclude that sc anti-D: is not only an efficient means of treating ITP in children but is also a safe and convenient one.

Investigation of whether the acute hemolysis associated with Rh(o)(D) immune globulin intravenous (human) administration for treatment of immune thrombocytopenic purpura is consistent with the acute hemolytic transfusion reaction model

BACKGROUND

Immune thrombocytopenic purpura and secondary thrombocytopenia patients treated with Rh(o)(D) immune globulin intravenous (human; anti-D IGIV) have experienced acute hemolysis, which is inconsistent with the typical presentation of extravascular hemolysis -- the presumed mechanism of action of anti-D IGIV. Although the mechanism of anti-D-IGIV-associated acute hemolysis has not been established, the onset, signs/symptoms, and complications appear consistent with the intravascular hemolysis of acute hemolytic transfusion reactions (AHTRs). In transfusion medicine, the red blood cell (RBC) antigen-antibody incompatibility(-ies) that precipitate AHTRs can be detected in vitro with compatibility testing. Under the premise that anti-D-IGIV-associated acute hemolysis results from RBC antigen-antibody-mediated complement activation, this study evaluated whether the incompatibility(-ies) could be detected in vitro with a hemolysin assay, which would support the AHTR model as the hemolytic mechanism.

STUDY DESIGN AND METHODS

Seven anti-D IGIV lots were tested to determine the RBC antibody identities in those lots, including four lots that had been implicated in acute hemolytic episodes. Hemolysin assays were performed that tested each of 73 RBC specimens against each lot, including the RBCs of one patient who had experienced acute hemolysis after anti-D IGIV administration.

RESULTS

Only two anti-D IGIV lots contained RBC antibodies beyond those expected. No hemolysis endpoint was observed in any of the hemolysin assays.

CONCLUSION

Although the findings did not support the AHTR model, the results are reported to contribute knowledge about the mechanism of anti-D-IGIV-associated acute hemolysis and to prompt continued investigation into cause(s), prediction, and prevention of this potentially serious adverse event.

Anti-D immunoglobulin-induced prolonged intravascular hemolysis and neutropenia

Intravenous anti-D immunoglobulin (anti-D IVIG) is indicated for the treatment of immune thrombocytopenic purpura (ITP) in nonsplenectomized patients who are Rh(D)-positive. Recent reports have described episodes of intravascular hemolysis after anti-D IVIG. We report an adolescent boy with chronic ITP who required multiple transfusions of erythrocyte suspensions when intravascular hemolysis persisted for 6 months after anti-D IVIG treatment. He did not have hemolytic anemia before treatment. The features of our case suggest that pediatric patients treated with anti-D IVIG for ITP should be closely monitored for signs and symptoms of hemoglobinemia and/or hemoglobinuria, and clinically significant anemia. Our case proposes that persistence of immune hemolysis after this treatment may be related to presence of previously defined predisposing agents like tuberculosis and antituberculous therapy. Our observations suggest that steroid therapy can be effective in patients who developed prolonged hemolytic anemia and neutropenia after anti-D IVIG therapy.

A review of anti-D treatment of childhood idiopathic thrombocytopenic purpura

Treatment of childhood idiopathic thrombocytopenic purpura is still an area of controversy. We reviewed the literature on anti-D treatment. Most studies used intravenous anti-D. Single doses of 50 microg/kg increased the platelet count to >or=20x10(9)/L in 70% of the children within 3 days. Intravenous anti-D seems safe in classic childhood ITP although hemolysis and occasionally renal failure may be of concern. A few studies reported intramuscularly or subcutaneously administered anti-D. Further studies on the optimal dose and route of administration of anti-D are warranted.

Recent advances in the treatment of childhood immune thrombocytopenic purpura

Immune thrombocytopenic purpura (ITP), the most common bleeding disorder in childhood, is a benign condition that typically resolves within 6 months following diagnosis. While all would agree on drug treatment for children with severe hemorrhage, management strategies of the minimally symptomatic child with a very low platelet count can vary widely. The case for treatment is based primarily on the risk for the uncommon complication of intracranial hemorrhage or other serious bleeding. Numerous clinical studies clearly indicate that immune globulins (intravenous immune globulin [IVIg] or anti-D) and corticosteroid therapy (prednisone and megadose methylprednisolone) are effective in rapidly raising platelet counts. However, physicians must ultimately decide whether to use drug therapy for a patient with minimal symptoms and low platelet count or adopt an "observation-only" approach. With this background, three fundamental questions emerge when evaluating different clinical strategies and potential outcomes: (1) Which children with ITP need treatment? (2) Which pharmacologic agent best accomplishes the goals of drug treatment? (3) Can physicians better predict the outcome of treatments?

Single dose of anti-D immune globulin at 75 microg/kg is as effective as intravenous immune globulin at rapidly raising the platelet count in newly diagnosed immune thrombocytopenic purpura in children

OBJECTIVE

To conduct a randomized prospective trial of immune globulin treatment for 105 Rh+ children with newly-diagnosed immune thrombocytopenic purpura and a platelet count<20,000/microL, to determine whether anti-D immune globulin (anti-D) is as effective as intravenous immune globulin (IVIg).

STUDY DESIGN

Eligible patients received either a single intravenous dose of 50 microg/kg anti-D (anti-D50), 75 microg/kg anti-D, (anti-D75), or 0.8 g/kg IVIg, (IVIg). Patients were monitored for response to treatment and adverse events.

RESULTS

By 24 hours after treatment 50%, 72%, and 77% of patients in the anti-D50, anti-D75, and IVIg groups, respectively, had achieved a platelet count>20,000/microL (P=.03). By day 7, hemoglobin concentrations decreased by 1.6 g/dL, 2 g/dL, and 0.3 g/dL in the anti-D50, anti-D75, and IVIg groups, respectively. Headache, fever, or chills occurred least often in the anti-D50 group.

CONCLUSIONS

A single 75 microg/kg dose of Anti-D raised the platelet count in children with newly diagnosed immune thrombocytopenic purpura more rapidly than standard-dose anti-D and as effectively as IVIg, with an acceptable safety profile.

Disseminated intravascular coagulation associated with acute hemoglobinemia or hemoglobinuria following Rho(D) immune globulin intravenous administration for immune thrombocytopenic purpura

The Food and Drug Administration (FDA) licensed Rho(D) immune globulin intravenous (anti-D IGIV) on March 24, 1995, for treatment of immune thrombocytopenic purpura (ITP). A previous review described data on 15 patients who experienced acute hemoglobinemia or hemoglobinuria following anti-D IGIV administration for ITP or secondary thrombocytopenia. Eleven of those patients also experienced clinically compromising anemia, transfusion with packed red blood cells, renal insufficiency, dialysis, or death. That review suggested that patients receiving anti-D IGIV be monitored for those and other potential complications of hemoglobinemia, particularly disseminated intravascular coagulation (DIC). Through November 30, 2004, the FDA received 6 reports of DIC associated with “acute hemolysis” (or similar terms), 5 of which involved fatalities. The attending or consulting physicians assessed that acute hemolysis or DIC caused or contributed to each death. This review presents the first case series of DIC associated with acute hemoglobinemia or hemoglobinuria following anti-D IGIV administration for ITP. The purpose of this review is to increase awareness among physicians and other health care professionals that DIC may be a rare but potentially severe complication of anti-D IGIV treatment. Increased awareness of DIC as a diagnostic possibility may enable prompt recognition and medical intervention in affected patients.

Chemical compounds that target thiol-disulfide groups on mononuclear phagocytes inhibit immune mediated phagocytosis of red blood cells

BACKGROUND

Patients having immune cytopenias produce antibodies that target hematopoietic cells resulting in their phagocytosis and intracellular destruction. Early reports suggested that phagocytosis could be inhibited by interfering with membrane thiol (SH) groups on phagocytes. Thus, whether chemical compounds that interact with SH or disulfide (SS) groups on mononuclear phagocytes can inhibit phagocytosis of antibody-coated cells was examined.

STUDY DESIGN AND METHODS

A monocyte monolayer assay (MMA), which examines the in vitro monocyte-macrophage (Mphi) interaction with anti-Rh(D)-coated red cells (RBCs), was used to study the ability of different SH and SS chemicals to inhibit the Fc receptor-mediated phagocytosis of sensitized RBCs. The compounds examined included thimerosal, dithiothreitol (DTT), pentane-1-thiol, and two recently described SH and two SS chemicals that have been synthesized.

RESULTS

All compounds were found to be able to inhibit phagocytosis to varying degrees correlating to the structure of the molecule. In general, those compounds that interact with free SH groups to inhibit phagocytosis were found better than SH-containing compounds that interact with SSs. Thimerosal and p-nitrophenyl methyl disulfide were the most effective compounds inhibiting phagocytosis. Both chemicals showed greater than 50 percent inhibition at concentrations as low as 10(-9) mol per L. DTT was the least effective compound tested. Only thimerosal showed significant toxicity, as determined by decreased cell viability and increased apoptosis, but only at concentrations of 10(-8) mol per L. The effect of chemical treatment was on attachment rather than on phagocytosis itself. Fcgamma receptor-independent endocytosis was not affected by the chemical treatment.

CONCLUSION

These studies indicate that pharmacologic strategies that target SH groups on mononuclear phagocytes may have future efficacy for the treatment of immune cytopenias.

The pros and cons of drug therapy for immune thrombocytopenic purpura in children

This article discusses the pros and cons of drug therapy for immune thrombocytopenic purpura in children.

After eight-year-tolerance minimal i.v. anti-D infusions unleash hemolysis in a patient with immune thrombocytopenic purpura (ITP)

Minimal doses of i.v. anti-D for ITP are not exempt from the risk of intravascular hemolysis, a rare potentially severe short-lived post-infusion complication. We report here on an elderly woman with chronic pancytopenia and splenomegaly in whom bleeding manifestations ceased after i.v. anti-Rh(D) immunoglobulin minidoses replaced long-term conventional treatment for immune thrombocytopenic purpura. Anti-Rh(D) infusions, that had been well tolerated for eight years, became the main culprit in triggering of disproportionate hemolysis. In spite of in crescendo complication, the anti-Rh(D) immunoglobulin schedule was maintained for another six months. With no further treatment, the patient's health remains stable 20 months later.