Characteristics and management of hypersensitivity reactions with rabbit anti-thymocyte globulin in pediatric patients

Background: Anti-thymocyte globulin (ATG) has been successfully used for decades to prevent graft versus host disease before hematopoietic stem cell transplantation (HSCT) as a part of conditioning regimen. However, sometimes hypersensitivity reactions may limit its use. Objective: To evaluate hypersensitivity reactions experienced during rabbit-ATG infusion among children and present successful desensitization protocol. Methods: The medical records of pediatric patients who were given rabbit-ATG treatment at our tertiary center hospital HSCT unit between 2019 and 2022 were reviewed retrospectively. Diagnosis of the patients, age at the time of HSCT, gender, presence of hypersensitivity reaction to rabbit-ATG, and management were evaluated. Characteristics of the reaction and presence of hypersensitivity reaction to other drugs were also noted. If performed, desensitization protocols were evaluated retrospectively. Results: We evaluated 81 patients; 66.6% of them (n = 54) were boys. The mean age of the patients was 8.78 ± 5.48 years. Hypersensitivity to rabbit-ATG was seen in six patients (7.4%). Four of them (4.9%) had anaphylaxis; two (2.4%) had urticaria. Intradermal test performed to every patient before the first dose of ATG infusion was detected a positive result in 1 patient (1.2%) . None of these seven patients had allergic reactions to other drugs before. Successful ATG desensitization was performed in five patients by using a 12-16 step protocol due to patients' reaction severity. Conclusion: This study aimed to evaluate hypersensitivity reactions with rabbit-ATG in children. A successful desensitization protocol with rabbit-ATG is presented. Desensitization must be performed with an experienced team very carefully in the absence of alternative drug.

Hematopoietic Cell Transplantation Cures Adenosine Deaminase 2 Deficiency: Report on 30 Patients

PURPOSE

Deficiency of adenosine deaminase 2 (DADA2) is an inherited inborn error of immunity, characterized by autoinflammation (recurrent fever), vasculopathy (livedo racemosa, polyarteritis nodosa, lacunar ischemic strokes, and intracranial hemorrhages), immunodeficiency, lymphoproliferation, immune cytopenias, and bone marrow failure (BMF). Tumor necrosis factor (TNF-α) blockade is the treatment of choice for the vasculopathy, but often fails to reverse refractory cytopenia. We aimed to study the outcome of hematopoietic cell transplantation (HCT) in patients with DADA2.

METHODS

We conducted a retrospective study on the outcome of HCT in patients with DADA2. The primary outcome was overall survival (OS).

RESULTS

Thirty DADA2 patients from 12 countries received a total of 38 HCTs. The indications for HCT were BMF, immune cytopenia, malignancy, or immunodeficiency. Median age at HCT was 9 years (range: 2-28 years). The conditioning regimens for the final transplants were myeloablative (n = 20), reduced intensity (n = 8), or non-myeloablative (n = 2). Donors were HLA-matched related (n = 4), HLA-matched unrelated (n = 16), HLA-haploidentical (n = 2), or HLA-mismatched unrelated (n = 8). After a median follow-up of 2 years (range: 0.5-16 years), 2-year OS was 97%, and 2-year GvHD-free relapse-free survival was 73%. The hematological and immunological phenotypes resolved, and there were no new vascular events. Plasma ADA2 enzyme activity normalized in 16/17 patients tested. Six patients required more than one HCT.

CONCLUSION

HCT was an effective treatment for DADA2, successfully reversing the refractory cytopenia, as well as the vasculopathy and immunodeficiency.

CLINICAL IMPLICATIONS

HCT is a definitive cure for DADA2 with > 95% survival.

Direct Antiglobulin Test Positivity in Children With Acute Lymphoblastic Leukemia at Diagnosis

Direct antiglobulin test positivity had been reported in the course of some lymphoproliferative neoplasms. However, there are a few case reports describing direct antiglobulin test (DAT) positivity in children with acute lymphoblastic leukemia (ALL). We herein report 8 patients who had positive DAT among 95 newly diagnosed children with ALL. None of these patients had evidence of hemolysis during the follow-up. An antibody was detected in 2 of 8 patients with positive DAT. These 2 children also had positive indirect antiglobulin test (IAT); an autoantibody that was reactive at 4°C, and an alloantibody (anti E) that was reactive at 37°C was detected. We believe DAT positivity in ALL without significant hemolysis is not a rare disorder, and a need for further prospective studies is apparent.

The successful non-invasive management of pulmonary thromboembolism in a child with acute lymphoblastic leukemia

In childhood, pulmonary thromboembolism (PTE) is an uncommonbut potentially life-threatening disease. The greater numbers of venous thromboembolism (VTE) are complications of underlying risk factors such as malignancies, chemotherapy (L-asparaginase), and central venous catheter. We report a patient with acute lymphoblastic leukemia and PTE, who presented with near-syncope, and was successfully treated with low molecular weight heparin and calcium channel blockers.

Numerous granulocyte transfusions to a patient with severe aplastic anemia without severe complication

One of the most important morbidity causes of aplastic anemia is invasive fungal infections. It could not be possible to take control of infection without neutrophils despite the recent developments in the antifungals. In this presented case, a patient with severe aplastic anemia, granulocyte transfusion were administered as 46 times because of the presence of widely invasive aspergillosis and resistance. Only fever reaction was observed as a complication of transfusion amongst the other complications such as acute lung damage, alloimmunisation, and graft-versus-host disease. Granulosit transfusions should not be avoided in patients who had an indication for.

Complete blood count using VCS (volume, conductivity, light scatter) technology is affected by hyperlipidemia in a child with acute leukemia

Asparaginase, an effective drug in the treatment of childhood acute lymphoblastic leukemia (ALL), has become an important component of most childhood ALL regimens during the remission induction or intensification phases of treatment. The incidence range of asparaginase-associated lipid abnormalities that are seen in children is 67-72%. Lipemia causes erroneous results, which uses photometric methods to analyze blood samples. We describe a case of l-asparaginase-associated severe hyperlipidemia with complete blood count abnormalities. Complete blood count analysis was performed with Beckman COULTER(®) GEN·S™ system, which uses the Coulter Volume, Conductivity, Scatter technology to probe hydrodynamically focused cells. Although an expected significant inaccuracy in hemoglobin determination occurred starting from a lipid value of 3450 mg/dl, we observed that triglyceride level was 1466 mg/dl. Complete blood count analysis revealed that exceptionally high hemoglobin, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration levels vs. discordant with red blood cell count, mean corpuscular volume, and hematocrit levels. Total leukocyte count altered spontaneously in a wide range, and was checked with blood smear. Platelet count was in expected range (Table 1). Thus, we thought it was a laboratory error, and the patient's follow-up especially for red cell parameters was made by red blood cell and hematocrit values.

A new hemostatic agent--Ankaferd blood stopper: management of gastrointestinal bleeding in an infant and other experiences in children

Ankaferd blood stopper (ABS) is a standardized medicinal plant extract that stimulates the formation of an encapsulated protein network that provides focal points for erythrocyte aggregation. It has a therapeutic potential to be used for the management of external hemorrhage. Here, the authors report an infant bleeding from peptic ulcer was stopped successfully by gastroscopic application of ABS and other cases that used topical ABS for mucosal bleedings are also presented.

Knowledge of, perception of, and attitudes toward epilepsy of schoolchildren in Ankara and the effect of an educational program

Epilepsy is one of the most common serious chronic brain disorders of childhood and carries a strong social stigma. It has been generally accepted that educational programs can be beneficial in reducing the stigma of a number of chronic diseases such as epilepsy. In this article, we describe the first Turkish survey of primary school students' knowledge of and attitudes toward epilepsy and the effect of an epilepsy education program on the understanding of epilepsy in schoolchildren attending three different upper-middle schools in the city of Ankara. The epilepsy education program was found to be associated with a significant increase in knowledge of and positive attitudes toward epilepsy. In addition, students at higher socioeconomic levels performed better on both pre- and posttests. This emphasizes the importance of an educational program and the need for continued information and support for education about epilepsy.