When to initiate immunoglobulin replacement therapy (IGRT) in antibody deficiency: a practical approach

Abstract

Summary Primary antibody deficiencies (PAD) constitute the majority of all primary immunodeficiency diseases (PID) and immunoglobulin replacement forms the mainstay of therapy for many patients in this category. Secondary antibody deficiencies (SAD) represent a larger and expanding number of patients resulting from the use of a wide range of immunosuppressive therapies, in particular those targeting B cells, and may also result from renal or gastrointestinal immunoglobulin losses. While there are clear similarities between primary and secondary antibody deficiencies, there are also significant differences. This review describes a practical approach to the clinical, laboratory and radiological assessment of patients with antibody deficiency, focusing on the factors that determine whether or not immunoglobulin replacement should be used. The decision to treat is more straightforward when defined diagnostic criteria for some of the major PADs, such as common variable immunodeficiency disorders (CVID) or X‐linked agammaglobulinaemia (XLA), are fulfilled or, indeed, when there is a very low level of immunoglobulin production in association with an increased frequency of severe or recurrent infections in SAD. However, the presentation of many patients is less clear‐cut and represents a considerable challenge in terms of the decision whether or not to treat and the best way in which to assess the outcome of therapy. This decision is important, not least to improve individual quality of life and reduce the morbidity and mortality associated with recurrent infections but also to avoid inappropriate exposure to blood products and to ensure that immunoglobulin, a costly and limited resource, is used to maximal benefit.

Measurement of Typhi Vi antibodies can be used to assess adaptive immunity in patients with immunodeficiency

“…Residual responses to vaccines, sometimes near to those observed in a normal population, have been shown previously in patients with hypogammaglobinaemia [16][17][18]. Total serum immunoglobulin levels alongside the functional information offered by vaccination responses and clinical assessment of infection burden are required to evaluate humoral immune function [19].…”

Current clinical practice and challenges in the management of secondary immunodeficiency in hematological malignancies

“…12,19 Additionally, pharmacokinetics may be preferable, as SCIG treatment leads to higher and more stable IgG trough levels, providing patients with a more consistent protection against infections. 1,20 The use of SCIG varies greatly between countries. For example, in Scandinavia, SCIG is used in 80%-90% of PID patients, while in Spain, France, and Italy IVIG is used predominantly.…”

Що необхідно знати педіатру про селективний дефіцит IgA (update 2017)

“…Крім того, зв'язок між целіакією та SIgAD може мати генетичну основу, зокрема деякі спільні HLA-гаплотипи, такі як HLA-A1, HLA-Cw7, HLA-B8, HLA-DR3 та HLA-DQ2. Гістопатологія целіакії при SIgAD відрізняється відсутністю IgA-секретуючих плазматичних клітин у зразках біопта-тів кишечника [11,12]. Оскільки целіакія найчастіше виявляється за наявністю IgA-антитіл до вищезгада-них білків (наприклад, трансглутамінази, гліадину та проламіну), у дітей із підозрою на SIgAD пропону-ється ідентифікувати IgG проти деамідованих пеп-тидів гліадину (deamidated gliadin peptide antibody) через високу специфічність для надійної діагности-ки целіакії в пацієнтів із SIgAD (рівень доказовості А) [11].…”

“…У деяких осіб рівень IgA без лікування поступово стає нормаль-ним. Часто в підлітковому віці може бути діагностова-ний загальний варіабельний імунодефіцит (common variable immunodeficiency) [12].…”