Carbamazepine-induced B-cell aplasia: Overlooked and overtreated

Overview of secondary immunodeficiency

In contrast to inborn errors of immunity (IEI), which are inherited disorders of the immune system that predispose to infections, malignancy, atopy, and immune dysregulation, secondary immunodeficiencies and immune dysregulation states (SID) are acquired impairments in immune cell function and/or regulation, and may be transient, reversible, or permanent. SIDs can derive from a variety of medical comorbidities, including protein-losing conditions, malnutrition, malignancy, certain genetic syndromes, prematurity, and chronic infections. Medications, including immunosuppressive and chemotherapeutic drugs, can have profound effects on immunity and biologic agents used in rheumatology, neurology, and hematology/oncology practice are increasingly common causes of SID. Iatrogenic factors, including surgical procedures (thymectomy, splenectomy) can also contribute to SID. A thorough case history, medication review, and laboratory evaluation are necessary to identify the primary driver and determine proper management of SID. Careful consideration should be given to whether a primary IEI could be contributing to autoimmunity, malignancy, and posttreatment complications (e.g., antibody deficiency). SID management consists of addressing the driving condition and/or removing the offending agent if feasible. If SID is suspected to be permanent, then antibiotic prophylaxis, additional immunization, and immunoglobulin replacement should be considered.

Practical guidance for the diagnosis and management of secondary hypogammaglobulinemia: A Work Group Report of the AAAAI Primary Immunodeficiency and Altered Immune Response Committees

Secondary hypogammaglobulinemia (SHG) is characterized by reduced immunoglobulin levels due to acquired causes of decreased antibody production or increased antibody loss. Clarification regarding whether the hypogammaglobulinemia is secondary or primary is important because this has implications for evaluation and management. Prior receipt of immunosuppressive medications and/or presence of conditions associated with SHG development, including protein loss syndromes, are histories that raise suspicion for SHG. In patients with these histories, a thorough investigation of potential etiologies of SHG reviewed in this report is needed to devise an effective treatment plan focused on removal of iatrogenic causes (eg, discontinuation of an offending drug) or treatment of the underlying condition (eg, management of nephrotic syndrome). When iatrogenic causes cannot be removed or underlying conditions cannot be reversed, therapeutic options are not clearly delineated but include heightened monitoring for clinical infections, supportive antimicrobials, and in some cases, immunoglobulin replacement therapy. This report serves to summarize the existing literature regarding immunosuppressive medications and populations (autoimmune, neurologic, hematologic/oncologic, pulmonary, posttransplant, protein-losing) associated with SHG and highlights key areas for future investigation.

Variable clinical characteristics and laboratory results in five patients with Chinese Good's syndrome (thymoma and hypogammaglobulinemia): an 8-year retrospective analysis in a university hospital in China

Background

Good's syndrome (GS) is a rare secondary immunodeficiency disease presenting as thymoma and hypogammaglobulinemia. Due to its rarity, the diagnosis of GS is often missed.

Methods

We used the hospital information system to retrospectively screen thymoma and hypogammaglobulinemia patients at the First Affiliated Hospital of Wenzhou Medical University from Apr 2012 to Apr 2020. The clinical, laboratory, treatment, and outcome data for these patients were collected and analyzed.

Results

Among the 181 screened thymoma patients, 5 thymoma patients with hypogammaglobulinemia were identified; 3 patients had confirmed diagnoses of GS, and the other 2 did not have a diagnosis of GS recorded in the hospital information system. A retrospective review of the clinical characteristics, laboratory results, and follow-up data for these 2 undiagnosed patients confirmed the diagnosis of GS. All 5 GS patients presented with pneumonia, 2 patients presented with recurrent skin abscesses, 2 patients presented with recurrent cough and expectoration, 1 patient presented with recurrent oral lichen planus and diarrhea, and 1 patient presented with tuberculosis and granulomatous epididymitis. In the years after the diagnosis of hypogammaglobulinemia with mild symptoms, all 5 patients had received irregular intravenous immunoglobulin (IVIG) treatment. As the course of the disease progressed, the clinical symptoms of all patients worsened, but the symptoms were partly resolved with IVIG in these patients. However, 4 patients died due to comorbidities.

Conclusion

GS should be investigated as a possible diagnosis in thymoma patients who present with hypogammaglobulinemia, especially those with recurrent opportunistic infections, recurrent skin abscesses, chronic diarrhea, or recurrent lichen planus.

A clinician survey for management of the secondary immunodeficiency caused by hematological malignancies in China

Unlike Western countries, there are still few clinical immunology specialists in China, and the optimal care for secondary immunodeficiency caused by hematological malignancies is unknown. Therefore, we initiated this clinician survey study to describe the current situation of the care for malignancy patients with hypogammaglobulinemia in China.We adapted a previously published online questionnaire of current clinical practices regarding the management of secondary immunodeficiency caused by hematological malignancies and then distributed the questionnaire to 52 hematologists in China via WeChat mobile software; the survey collected demographic details, starting dosage, target immunoglobulin (Ig) level, monitoring, criteria for stopping Ig replacement, vaccination use, and oral antibiotic prophylaxis for hypogammaglobulinemia patients.Forty-eight hematologists responded. 28(58.33%) respondents had more than 10 years of experience. Nevertheless, 40(83.33%) respondents reported that they did not use any specific criteria for prophylactic Ig replacement in hypogammaglobulinemia patients. However, 27(56.25%) respondents reported that they had used intravenous immunoglobulin (IVIG); however, the starting dose, frequency, and target Ig level were significantly varied. Additionally, the criteria for stopping Ig replacement were significantly varied. Only one respondent (2.08%) used subcutaneous immunoglobulin (SCIG). Moreover, 35(72.92%) respondents reported no vaccination prior to Ig replacement, and 47(97.92%) respondents reported that they had not used antibiotic prophylaxis in secondary hypogammaglobulinemia patients.Official guideline for the care for secondary immunodeficiency (SID) of the hematological malignancies patients should be issued in China, and significant attention of the hematologists should be paid to the use of prophylactic antibiotics and Ig replacement for the care of patients with hypogammaglobulinemia caused by hematological malignancies, as these agents could significantly reduce the infection rate in China.

Biosensors for Detecting Lymphocytes and Immunoglobulins

Lymphocytes (B, T and natural killer cells) and immunoglobulins are essential for the adaptive immune response against external pathogens. Flow cytometry and enzyme-linked immunosorbent (ELISA) kits are the gold standards to detect immunoglobulins, B cells and T cells, whereas the impedance measurement is the most used technique for natural killer cells. For point-of-care, fast and low-cost devices, biosensors could be suitable for the reliable, stable and reproducible detection of immunoglobulins and lymphocytes. In the literature, such biosensors are commonly fabricated using antibodies, aptamers, proteins and nanomaterials, whereas electrochemical, optical and piezoelectric techniques are used for detection. This review describes how these measurement techniques and transducers can be used to fabricate biosensors for detecting lymphocytes and the total content of immunoglobulins. The various methods and configurations are reported, along with the advantages and current limitations.

The epidemiology and clinical feature of selective immunoglobulin a deficiency of Zhejiang Province in China

Background

Selective immunoglobulin A deficiency (SIgAD) is the most common primary antibody deficiency disease and frequently reported in the Western countries. However, large‐scale epidemiologic studies on SIgAD in China are still lacking.

Methods

The clinical information of 555 180 subjects (age >4 years) including the outpatient, inpatient, and healthy subjects who had ordered serum immunoglobulin A, G, M in 9 hospitals of Zhejiang Province in China was collected. The SIgAD individuals were defined as IgA level <0.07 g/L with normal levels of serum IgG and IgM, whose age should be over 4 years, and any other secondary diseases causing SIgAD were also excluded. Then, the geographical and prevalence distribution of SIgAD individuals in Zhejiang Province and patients' clinical characteristics at the time of diagnosis were also reviewed.

Result

Among these 555 180 subjects who had ordered the immunoglobulin evaluation, the prevalence of SIgAD was 109/555180 (0.02%). The ratio of male to female of these SIgAD individuals was 1:1.37, which also included 87 adults (≥18 years) and 22 children (18 > age >4 years). For adults, the common clinical features were infections (43/87, 49.43%), autoimmune disorders (31/87, 35.63%), allergic cases (5/87, 5.75%), and tumor cases (4/87, 4.60%). Additionally, infectious diseases (20/22, 90.91%), autoimmune disorders (4/22, 18.18%), and allergic cases (1/22, 4.55%) were found in 22 children.

Conclusion

We first describe a large cohort of SIgAD individuals of Zhejiang Province in China. The incidence was 0.020%. The common clinical features were infection, autoimmune disorders, tumor, and allergy, and the infection rate was higher in children than the adults.