Anti-Inflammatory and Immunomodulatory Effect of High-Dose Immunoglobulins in Children: From Approved Indications to Off-Label Use.

BACKGROUND: The large-scale utilization of immunoglobulins in patients with inborn errors of immunity (IEIs) since 1952 prompted the discovery of their key role at high doses as immunomodulatory and anti-inflammatory therapy, in the treatment of IEI-related immune dysregulation disorders, according to labelled and off-label indications. Recent years have been dominated by a progressive imbalance between the gradual but constant increase in the use of immunoglobulins and their availability, exacerbated by the SARS-CoV-2 pandemic. OBJECTIVES: To provide pragmatic indications for a need-based application of high-dose immunoglobulins in the pediatric context. SOURCES: A literature search was performed using PubMed, from inception until 1st August 2023, including the following keywords: anti-inflammatory; children; high dose gammaglobulin; high dose immunoglobulin; immune dysregulation; immunomodulation; immunomodulatory; inflammation; intravenous gammaglobulin; intravenous immunoglobulin; off-label; pediatric; subcutaneous gammaglobulin; subcutaneous immunoglobulin. All article types were considered. IMPLICATIONS: In the light of the current imbalance between gammaglobulins' demand and availability, this review advocates the urgency of a more conscious utilization of this medical product, giving indications about benefits, risks, cost-effectiveness, and administration routes of high-dose immunoglobulins in children with hematologic, neurologic, and inflammatory immune dysregulation disorders, prompting further research towards a responsible employment of gammaglobulins and improving the therapeutical decisional process.

Autoimmune basal ganglia encephalitis associated with anti-recoverin antibodies: A case report.

Autoimmune basal ganglia encephalitis causes neurological symptoms such as parkinsonism associated with basal ganglia lesions. Here, we report a case of autoimmune basal ganglia encephalitis without retinal lesions or malignancy harboring anti-recoverin antibodies. The patient was a 67-year-old Japanese woman who developed anorexia, parkinsonism, and disturbance of consciousness 7 days before admission. Brain magnetic resonance imaging showed hyperintense bilateral basal ganglia lesions on fluid-attenuated inversion recovery images. 18F-fluorodeoxyglucose-positron emission tomography showed no malignancy in the trunk, and dopamine transporter single-photon emission computed tomography with dopamine transporters revealed reduced radiotracer uptake in the basal ganglia. Further, anti-recoverin IgG antibodies were detected in serum immunoblot. Based on the clinical and imaging findings, the patient was diagnosed with autoimmune basal ganglia encephalitis with anti-recoverin antibodies and administered high-dose immunoglobulins (HD-IVIG), which led to an improvement in clinical symptoms. Anti-recoverin antibodies are paraneoplastic antibodies that explicitly bind to Ca2+-binding proteins in the retina and cause retinopathy. This pathological sequence is defined as cancer-associated retinopathy (CAR). However, in our case, autoimmune basal ganglia encephalitis developed without CAR syndrome or malignancy. Clinicians should be aware of the possibility of autoimmune basal ganglia encephalitis showing anti-recoverin antibodies but no CAR syndrome or malignancy, which should be treated with HD-IVIG therapy.

The Japanese experience and pharmacokinetics of antenatal maternal high-dose immunoglobulin treatment as a prophylaxis for neonatal hemochromatosis in siblings.

Background: Neonatal hemochromatosis (NH) is a rare but serious disease causing fulminant hepatic failure. The recurrence rate of NH in a subsequent infant of a mother with an affected infant is 70-90%. Recently, antenatal maternal high-dose intravenous immunoglobulin (IVIG) treatment has been reported to be effective for preventing NH recurrence. However, data on the IgG concentrations during this treatment are limited.Objective: We report a Japanese experience and present a pharmacokinetic simulation model of IgG during IVIG treatment.Methods: Women with histories of pregnancy diagnosed with NH were treated with IVIG weekly from the second trimester until the end of gestation. Serum IgG levels during treatment were collected frequently and pharmacokinetics were simulated by a two-compartment model.Results: Six women were included during eight pregnancies. None experienced severe adverse events. Three out of eight infants showed temporary liver dysfunction, but none required any treatment. A simulation study showed that the estimated trough and peak levels of IgG concentrations during IVIG were 2000-3000 and 4000-5000 mg/dl, respectively.Conclusion: This treatment prevented the recurrence of NH in siblings in Japanese women. We examined the details of serum IgG concentrations and introduced a new pharmacokinetic simulation model of IgG concentrations during IVIG treatment.

New insights on scleromyxedema.

Scleromyxedema is a rare fibromucinous disorders, with several clinical and pathological overlaps with scleroderma and scleredema. Etiopathogenesis remains uncovered, and no explanation has been provided either for the origin of mucin deposition or for the paraprotein role. The disease does not show gender predilection and affects mainly middle-age adults. The course is unpredictable, and prognosis remains guarded for renal, cardiac, and neurologic complications, especially in the setting of dermato-neuro syndrome. A valuable recent progress is the consensus definition of diagnostic criteria and lines of treatment, which hold the promise to improve the early recognition and management of this rare condition worldwide. High-dose intravenous immunoglobulin has been suggested as the first-line treatment either alone or associated with systemic steroids and/or thalidomide. In very recalcitrant cases, adjunctive bortezomib and/or autologous stem cell transplant might be considered. Melphalan treatment was associated with very toxic side effects and actually is no longer recommended.

Acute Intravascular Haemolysis Associated with High Dose Immunoglobulin after Bone Marrow Transplantation for Acute Myelogenous Leukemia.

A 12-year-old boy developed persistent thrombocytopenia after undergoing bone marrow transplantation for acute myelogenous leukemia. High doses of intravenous immunoglobulins were used to treat overt hemorrhage and a sudden intravascular hemolysis occurred. The serologic findings point to an acute hemolysis secondary to the presence of isohemoagglutinins in the intravenous immunoglobulin preparations.

A Case of Off-Pump Coronary Artery Bypass Grafting Following High-Dose Dexamethasone Therapy in a Patient with Idiopathic Thrombocytopenic Purpura / 日本心臓血管外科学会雑誌

Man in his 70s, who had suffered from idiopathic thrombocytopenic purpura (ITP), was admitted to our hospital with chest pain at rest. Coronary angiography revealed obstruction of the right coronary artery and triple vessel disease. Because a bleeding tendency was expected during coronary artery bypass grafting, we performed percutaneous coronary intervention to the culprit lesion first, and then intravenous immunoglobulin and high dose dexamethasone were tried. His platelet count rose from 49,000 to 103,000/mm3, so we performed coronary artery bypass grafting. The patient had no postoperative hemorrhagic complications. We believe that high dose dexamethasone therapy is useful for patients with ITP who need surgery immediately.