Immunoglobulin replacement for selective IgM immunodeficiency, bronchiectasis, and asthma

Selective IgM Deficiency: Evidence, Controversies, and Gaps

Selective Immunoglobulin M deficiency (SIgMD) has been recently included in the inborn errors of immunity (IEI) classification by the International Union of Immunological Societies Expert Committee. The understanding of SIgMD is still extremely limited, especially so in cases of SIgMD in the pediatric population. The epidemiology of SIgMD in the pediatric population is still unknown. The pathogenesis of SIgMD remains elusive, and thus far no genetic nor molecular basis has been clearly established as a definitive cause of this primary immunodeficiency. Recurrent respiratory infections represent the main clinical manifestations in children, followed by allergic and autoimmune diseases. No conclusive data on the correct therapeutic management of SIgMD are available. Although, for most SIgMD patients, Ig replacement therapy is not required, it may be recommended for patients with significantly associated antibody deficiency and recurrent or severe infections. Prophylactic antibiotics and the prompt treatment of febrile illness are crucial. There is insufficient evidence on the prognosis of this condition. Therefore, further studies are required to define the disease trajectories and to increase our understanding of the molecular mechanisms underlying SIgMD in order to facilitate a better clinical, immunological, and prognostic characterization of the condition and develop tailored therapeutic management strategies.

Spectrum of Disease Manifestations in Patients with Selective Immunoglobulin E Deficiency

BACKGROUND

Selective IgE deficiency (SIgED) has been previously evaluated in selected patients from allergy units. This study investigates the effects of SIgED on the entire population in a hospital setting and sought to delineate in detail the clinical aspects of SIgED.

METHODS

A retrospective study of the data obtained from electronic medical records of 52 adult patients (56% female) with a mean age of 43 years and IgE levels of <2.0 kU/L with normal immunoglobulin (Ig) IgG, IgA, and IgM levels, seen at our hospital, without selection bias, from 2010 to 2019.

RESULTS

Recurrent upper respiratory infections were recorded in 18 (34.6%) patients, pneumonia was recorded in 16 (30.7%) patients, bronchiectasis was recorded in 16 (30.7%) patients, and asthma was recorded in 10 (19.2%) patients. Eighteen patients (34.6%) suffered autoimmune clinical manifestations either isolated (19%) or combining two or more diseases (15%), Hashimoto's thyroiditis being the most frequent (19%), which was followed by arthritis (10%) and thrombocytopenia and/or neutropenia (5.7%). Other less frequent associations were Graves' disease, primary sclerosing cholangitis, Sjögren's syndrome, and autoimmune hepatitis. Eczematous dermatitis (15.3%), chronic spontaneous urticaria (17.3%), and symptoms of enteropathy (21%) were also highly prevalent. Thirty percent of patients developed malignancies, with non-Hodgkin lymphomas (13.4%) being the most prevalent.

CONCLUSIONS

The clinical manifestations of SIgED encompass a variety of infectious, non-infectious complications, and malignancy. Since it cannot be ruled out that some type of selection bias occurred in the routine assessment of IgE serum Ievels, prospective studies are required to better characterize SIgED and to determine whether it should be added to the list of antibody deficiencies.

Selective immunoglobulin M deficiency complicated by systemic lupus erythematosus and antiphospholipid syndrome: a case report and review of literature

Selective immunoglobulin M deficiency (SIgMD) is the isolated absence of serum immunoglobulin M (IgM) with normal levels of other serum immunoglobulins. SIgMD is associated with infections and autoimmune diseases. While there are few reports on SIgMD complicated by systemic lupus erythematosus (SLE), there are no reports on SIgMD complicated by SLE and antiphospholipid syndrome (APS); we present the first report of this kind. A 61-year-old Japanese woman presented with microscopic hematuria and proteinuria. Clinical investigations revealed an elevated serum creatinine level, an undetectable serum IgM level, and seropositivity of antinuclear antibody, anti-Smith antibody, and double-stranded DNA antibody. Radiological investigations were unremarkable. Renal biopsy revealed focal and segmental mesangial cell proliferation; thickened glomerular capillary walls; and IgG, IgA, C3, and C1q deposition, which indicated class III (A/C) lupus nephritis (Renal Pathology Society/International Society of Nephrology classification). Furthermore, anti-CLβ2GP1 antibody positivity and deep vein thrombosis were noted, which fulfilled the revised Sapporo classification criteria for the diagnosis of APS. Thus, she was diagnosed with SIgMD complicated by SLE and APS. The patient was treated with prednisolone, mycophenolate mofetil, and warfarin. After a 1-year follow-up, she achieved clinical remission of SLE and APS without infectious complications; however, the serum IgM level remained undetectable. In conclusion, SIgMD can be complicated by autoimmune disorders. Although rare, we recommend that SLE and APS be considered in patients with SIgMD who present with hematuria, proteinuria, and deep vein thrombosis. We also recommend measuring the titers of antinuclear antibodies, double-stranded DNA antibodies, and anti-CLβ2GP1 antibodies.

SARS-CoV-2 Inflammatory Syndrome. Clinical Features and Rationale for Immunological Treatment

The current pandemic coronavirus, SARS-CoV-2, is a global health emergency because of its highly contagious nature, the great number of patients requiring intensive care therapy, and the high fatality rate. In the absence of specific antiviral drugs, passive prophylaxis, or a vaccine, the treatment aim in these patients is to prevent the potent virus-induced inflammatory stimuli from leading to the acute respiratory distress syndrome (ARDS), which has a severe prognosis. Here, the mechanism of action and the rationale for employing immunological strategies, which range from traditional chemically synthesized drugs, anti-cytokine antibodies, human immunoglobulin for intravenous use, to vaccines, are reviewed.

SARS-CoV-2 Inflammatory Syndrome. Clinical Features and Rationale for Immunological Treatment

The current pandemic coronavirus, SARS-CoV-2, is a global health emergency because of its highly contagious nature, the great number of patients requiring intensive care therapy, and the high fatality rate. In the absence of specific antiviral drugs, passive prophylaxis, or a vaccine, the treatment aim in these patients is to prevent the potent virus-induced inflammatory stimuli from leading to the acute respiratory distress syndrome (ARDS), which has a severe prognosis. Here, the mechanism of action and the rationale for employing immunological strategies, which range from traditional chemically synthesized drugs, anti-cytokine antibodies, human immunoglobulin for intravenous use, to vaccines, are reviewed.

Selective IgM Deficiency-An Underestimated Primary Immunodeficiency

Although selective IgM deficiency (SIGMD) was described almost five decades ago, it was largely ignored as a primary immunodeficiency. SIGMD is defined as serum IgM levels below two SD of mean with normal serum IgG and IgA. It appears to be more common than originally realized. SIGMD is observed in both children and adults. Patients with SIGMD may be asymptomatic; however, approximately 80% of patients with SIGMD present with infections with bacteria, viruses, fungi, and protozoa. There is an increased frequency of allergic and autoimmune diseases in SIGMD. A number of B cell subset abnormalities have been reported and impaired specific antibodies to Streptococcus pneumoniae responses are observed in more than 45% of cases. Innate immunity, T cells, T cell subsets, and T cell functions are essentially normal. The pathogenesis of SIGMD remains unclear. Mice selectively deficient in secreted IgM are also unable to control infections from bacterial, viral, and fungal pathogens, and develop autoimmunity. Immunological and clinical similarities and differences between mouse models of deficiency of secreted IgM and humans with SIGMD have been discussed. Patients with SIGMD presenting with recurrent infections and specific antibody deficiency responses appear to improve clinically on immunoglobulin therapy.

Effects of Immunoglobulin Replacement on Asthma Exacerbation in Adult Asthmatics with IgG Subclass Deficiency

Purpose

Recurrent respiratory tract infection is a common manifestation of primary immunodeficiency disease, and respiratory viruses or bacteria are important triggers of asthma exacerbations. Asthma often coexists with humoral immunodeficiency in adults, and some asthmatics with immunoglobulin (Ig) G subclass deficiency (IgGSCD) suffer from recurrent exacerbations. Although some studies suggest a benefit from Ig replacement, others have failed to support its use. This study aimed to assess the effect of Ig replacement on asthma exacerbation caused by respiratory infection as well as the asthma control status of adult asthmatics with IgGSCD.

Methods

This is a multi-center, open-label study of adult asthmatics with IgGSCD. All patients received monthly intravenous immunoglobulin (IVIG) for 6 months and were evaluated regarding asthma exacerbation related to infection, asthma control status, quality of life, and lung function before and after IVIG infusion.

Results

A total of 30 patients were enrolled, and 24 completed the study. Most of the patients had a moderate degree of asthma severity with partly (52%) or uncontrolled (41%) status at baseline. IVIG significantly reduced the proportion of patients with asthma exacerbations, lowered the number of respiratory infections, and improved asthma control status, compared to the baseline values (P<0.001). The mean asthma-specific quality of life and asthma control test scores were improved significantly (P=0.009 and P=0.053, respectively); however, there were no significant changes in lung function.

Conclusions

IVIG reduced the frequency of asthma exacerbations and improved asthma control status in adult asthmatics with IgGSCD, suggesting that IVIG could be an effective treatment option in this population.