Immunologic Effects of Heparin Associated With Hemodialysis: Focus on Heparin-Induced Thrombocytopenia

Intermittent hemodialysis (HD) is almost invariably performed with heparin, and thus HD patients are at risk of developing the immune-mediated adverse effect heparin-induced thrombocytopenia (HIT), caused by anti-platelet factor 4/heparin IgG, which strongly activates platelets. HIT patients develop hypercoagulability with greatly increased risk of thrombosis, both venous and arterial. Certain HIT-associated complications are more likely to develop among HD patients, including hemofilter thrombosis despite heparin, intravascular catheter and/or arteriovenous fistula-associated thrombosis, post-heparin bolus anaphylactoid/anaphylactic reactions, and thrombotic stroke and acute limb artery thrombosis (reflecting the high frequency of underlying arteriopathy in many patients with renal failure). Management of HIT in HD usually requires use of an alternative (non-heparin) anticoagulant; for example, danaparoid sodium (outside the USA) or argatroban (USA and elsewhere). Whether heparin-grafted hemodialyzers (without systemic heparin) can be used safely in acute HIT is unknown. The HIT immune response is remarkably transient and usually not retriggered by subsequent heparin administration. Accordingly, since renal failure patients often require long-term HD, there may be the opportunity-following seroreversion (loss of platelet-activating HIT antibodies)-to restart heparin for HD, a practice that appears to have a low likelihood of retriggering HIT.

Monoclonal antibody infusion reaction with bamlanivimab and etesevimab in a 5-year-old male with coronavirus disease 2019: a case report

BACKGROUND

Bamlanivimab and etesevimab had been granted emergency use authorization in children under 12 years who are at risk of progression from mild/moderate coronavirus disease 2019 to severe disease and hospitalization.

CASE REPORT

We report on a 5-year-old white male with preexisting conditions, predisposing him to severe disease, who developed hypoxia and flushing 3 minutes into his infusion, thus meeting the criteria for anaphylaxis.

CONCLUSIONS

We believe this patient developed either an immunoglobulin E-mediated anaphylactic or a non-immunoglobulin E-mediated anaphylactoid reaction to bamlanivimab and etesevimab, which is an important possibility to consider on administration.

Anaphylaxis in Children and Adolescents

Anaphylaxis is an acute, potentially life-threatening systemic hypersensitivity reaction. Classically, anaphylaxis is an immunoglobulin (Ig) E-mediated reaction; however, IgG or immune complex complement-related immunologic reactions that lead to degranulation of mast cells can also cause anaphylaxis. Food allergy is the most common cause of anaphylaxis, followed by drugs. Patients with anaphylaxis commonly present with symptoms involving skin or mucous membranes, followed by respiratory and gastrointestinal symptoms. Epinephrine is the drug of choice for treating anaphylaxis. Patients and caregivers should be educated on the use of epinephrine autoinjectors with periodic review of symptoms and emergency action plan for anaphylaxis.

Non-IgE-Mediated Drug Hypersensitivity Reactions

PURPOSE OF REVIEW

Non-IgE-mediated drug reactions have traditionally been poorly defined and studied, though they are the most common form of hypersensitivity. Their presentations are highly variable and can range in severity from mild, cutaneous-only reactions to severe systemic disease.

RECENT FINDINGS

The most notable advance in non-IgE-mediated hypersensitivity reactions is in diagnostics. HLA alleles have traditionally been used for identifying certain patients at risk for abacavir hypersensitivity syndrome, but more recent studies have shown several other HLA alleles associated with severe cutaneous adverse reactions with various medications. This article also highlights the use of delayed intradermal testing for radiocontrast media and patch testing for delayed antibiotic reactions. Drug reactions remain a major cause of morbidity and reason for treatment changes. Non-IgE-mediated reactions have had an increase in research interest over the past decade with an increased emphasis on better understanding the clinical presentation and underlying pathophysiology.

Anaphylaxis in Children and Adolescents

Anaphylaxis is an acute, potentially life-threatening systemic hypersensitivity reaction. Classically, anaphylaxis is an immunoglobulin (Ig) E-mediated reaction; however, IgG or immune complex complement-related immunologic reactions that lead to degranulation of mast cells can also cause anaphylaxis. Food allergy is the most common cause of anaphylaxis, followed by drugs. Patients with anaphylaxis commonly present with symptoms involving skin or mucous membranes, followed by respiratory and gastrointestinal symptoms. Epinephrine is the drug of choice for treating anaphylaxis. Patients and caregivers should be educated on the use of epinephrine autoinjectors with periodic review of symptoms and emergency action plan for anaphylaxis.

Severe hypersensitivity allergic reaction to filgrastim in a healthy stem cell donor

INTRODUCTION

Granulocyte-colony stimulating factor (G-CSF) has been approved for use for mobilization of hematopoietic progenitor cells from the marrow into the blood for peripheral blood stem cell collection. Commonly reported side effects of G-CSF include deep throbbing bone pain, severe myalgia and leucocytosis.

CASE REPORT

We describe a case of severe hypersensitivity anaphylactoid reaction after filgrastim administration in a healthy stem cell donor. This haploidentical donor was a 38-year old man with sickle cell trait, donating stem cells for his son, a case of sickle cell disease. On administration of G-CSF (10 µg/kg) he developed features of anaphylaxis.

MANAGEMENT AND OUTCOME

He was given supportive care with oxygen, IV fluid bolus, anti histaminics and steroids. The donor had complete recovery and underwent successful bone marrow harvest.

CONCLUSION

There have been various reports of hypersensitivity anaphylactoid reactions in patients undergoing chemotherapy but those associated with the first dose of G-CSF in healthy stem cell donors have rarely been reported.

Managing Adverse Reactions to Contrast Agents

Adverse reactions to iodinated and gadolinium-based contrast agents occur at an incidence of less than 1%. Although the exact pathophysiologic mechanisms are not completely understood, the treatment regimens are well accepted. Skin testing may be helpful in patients with a history of severe allergiclike reaction to aid in the selection of alternative contrast agents. Premedication should only be used for a history of allergiclike reaction. Imaging team members should be familiar with signs and symptoms of contrast reactions to allow for prompt assessment and treatment. A plan of action should be in place for contrast reactions and rehearsed regularly.

Is Andrographis paniculata extract and andrographolide anaphylactic?

Andrographis paniculata, "King of bitters" is a popularly known medicinal plant extensively used in many parts of the world for treatment of various diseases. Since recent past, anaphylactic/allergic type adverse events were reported upon A. paniculata usage, the study aimed to evaluate the anaphylactic and anaphylactoid potential of A. paniculata extract and andrographolide (a major phytoactive of A. paniculata). The anaphylactic potential was evaluated using active systemic anaphylaxis (ASA) assay in guinea pigs. Further, the release of allergic mediators was measured in immunoglobulin E (IgE) sensitized and non-IgE sensitized Rat Basophilic Leukemia (RBL-2H3) cell lines in-vitro. A. paniculata extract or andrographolide sensitized guinea pigs following the challenge antigen administration orally and intravenously did not demonstrate any clinical signs of anaphylaxis. IgE sensitized and non- IgE sensitized RBL-2H3 cells treated with A. paniculata extract did not induce release of allergic mediators. Whereas IgE sensitized and non- IgE sensitized RBL-2H3 cells treated with andrographolide demonstrated mild to moderate release of allergic mediators. A. paniculata extract has no anaphylactic and anaphylactoid potential in in-vivo and in-vitro studies. Whereas, andrographolide effects on allergic mediators in in-vitro studies needs to be scrutinized if they are of biologically important.

Characterization of Vancomycin Reactions and Linezolid Utilization in the Pediatric Population

BACKGROUND

Red man syndrome (RMS) occurs because of non-IgE-mediated histamine release. Unlike vancomycin allergy, which necessitates the use of an alternative drug (often linezolid), RMS does not typically preclude further vancomycin use. Care should be taken to differentiate these reaction types from one another to prevent unnecessary vancomycin avoidance.

OBJECTIVE

To characterize vancomycin reaction types in our population, and to determine whether having a reaction consistent with RMS is associated with otherwise unexplained vancomycin avoidance and linezolid use.

METHODS

We retrospectively reviewed charts for children with documented vancomycin reactions. We classified the in-hospital reactions via an objective analysis and estimated the prevalence of different reaction types. We then identified children who received linezolid over 3 years, and investigated reasons for linezolid use instead of vancomycin.

RESULTS

Of the 78 in-hospital reactions we characterized, 72 (92%) were objectively consistent with RMS, 5 we could not objectively classify (2 most likely RMS, 3 more suspicious for possible IgE-mediated allergy), and 1 was a non-RMS/non-IgE reaction. Of 60 children who received linezolid, 19 had previous reactions consistent with RMS, which should not preclude further vancomycin. Nevertheless, only 7 of 19 (37%) had a clear explanation for receiving linezolid instead of vancomycin compared with 32 of 39 (82%) children without previous vancomycin reactions (P < .001).

CONCLUSIONS

The vast majority of patients had vancomycin reactions consistent with RMS. These patients are at risk for unnecessary vancomycin avoidance and linezolid utilization. We propose that this may be related to how reactions appear in the electronic medical record.

Nonclinical evaluation of the potential for mast cell activation by an erythropoietin analog

The erythropoietin analog peginesatide was withdrawn from marketing due to unexpected severe anaphylactic reactions associated with administration of the multi-use formulation. The adverse events occurred rapidly following the first ever administration of the drug with most affected patients becoming symptomatic in less than 30min. This is most consistent with an anaphylactoid reaction due to direct activation of mast cells. Laboratory evaluation was undertaken using rat peritoneal mast cells as the model system. Initial studies showed that high concentrations of the formulated drug as well as formulated vehicle alone could cause mast cell degranulation as measured by histamine release. The purified active drug was not able to cause histamine release whereas the vehicle filtrate and lab created drug vehicle were equally potent at causing histamine release. Individual formulations of vehicle leaving one component out showed that histamine release was due to phenol. Dose response studies with phenol showed a very sharp dose response curve that was similar in three buffer systems. Cellular analysis by flow cytometry showed that the histamine release was not due to cell death, and that changes in light scatter parameters consistent with degranulation were rapidly observed. Limited testing with primary human mast cells showed a similar dose response of histamine release with exposure to phenol. To provide in vivo confirmation, rats were injected with vehicle formulated with various concentrations of phenol via a jugular vein cannula. Significant release of histamine was detected in blood samples taken 2min after dosing at the highest concentrations tested.

Hypersensitivity to laminaria: a case report and review of literature

We report a case of laminaria hypersensitivity treated with diphenhydramine and corticosteroids. A literature review identified 10 previously reported cases, with 8 recognized as anaphylaxis, and good outcomes with corticosteroids and antihistamines despite limited epinephrine utilization. Laminaria hypersensitivity is likely IgE mediated with an increased anaphylaxis risk with prior exposure.

Management of allergy and anaphylaxis during oral surgery

Minor and major allergic reactions occur during oral and maxillofacial treatment. Immediate diagnosis and pharmacologic intervention are imperative. Signs and symptoms may be variable. The early administration of epinephrine is critical.