Prospective, randomized comparison of OM-85 BV and a prophylactic antibiotic in children with recurrent infections and immunoglobulin A and/or G subclass deficiency

The Epidemiology and Clinical Presentations of Atopic Diseases in Selective IgA Deficiency

Selective IgA deficiency (sIgAD) is the most common primary immunodeficiency disease (PID), with an estimated occurrence from about 1:3000 to even 1:150, depending on population. sIgAD is diagnosed in adults and children after the 4th year of age, with immunoglobulin A level below 0.07 g/L and normal levels of IgM and IgG. Usually, the disease remains undiagnosed throughout the patient's life, due to its frequent asymptomatic course. If symptomatic, sIgAD is connected to more frequent viral and bacterial infections of upper respiratory, urinary, and gastrointestinal tracts, as well as autoimmune and allergic diseases. Interestingly, it may also be associated with other PIDs, such as IgG subclasses deficiency or specific antibodies deficiency. Rarely sIgAD can evolve to common variable immunodeficiency disease (CVID). It should also be remembered that IgA deficiency may occur in the course of other conditions or result from their treatment. It is hypothesized that allergic diseases (e.g., eczema, rhinitis, asthma) are more common in patients diagnosed with this particular PID. Selective IgA deficiency, although usually mildly symptomatic, can be difficult for clinicians. The aim of the study is to summarize the connection between selective IgA deficiency and atopic diseases.

Study protocol for a randomised controlled trial evaluating the clinical effect of antibiotic prophylaxis in children with recurrent respiratory tract infections: the Approach study

INTRODUCTION

Respiratory tract infections (RTIs) affect children all over the world and are associated with significant morbidity and mortality. In particular, recurrent RTIs cause a high burden of disease and lead to frequent doctor visits. Children with recurrent RTIs generally have no significant alterations or deficits in systemic immunity. In an attempt to treat the assumed bacterial component involved, they are often treated with prolonged courses of prophylactic antibiotics taken on a daily basis. Despite its common use, there is no evidence that this is beneficial. Studies assessing the clinical effectiveness of antibiotic prophylaxis as well as potential adverse effects and antibiotic resistance development, are therefore urgently needed.

METHODS AND ANALYSIS

We present a protocol for a randomised double-blind placebo-controlled trial comparing co-trimoxazole with placebo treatment in children with recurrent RTIs. A total of 158 children (aged 6 months-10 years) with recurrent RTIs without significant comorbidity will be enrolled from a minimum of 10 Dutch hospitals. One group receives co-trimoxazole 18 mg/kg two times per day (36 mg/kg/day) and the other group receives a placebo two times per day for a period of 3 months. The main objective is to determine whether antibiotic prophylaxis is more effective than placebo to prevent/reduce respiratory symptoms in children with recurrent RTIs. Respiratory symptoms will be scored by parents on a daily basis in both study arms by the use of a mobile phone application. Our primary outcome will be the number of days with at least two respiratory symptoms during the treatment.

ETHICS AND DISSEMINATION

Ethics approval was obtained from the Medical Ethics Research Committee Zuidwest Holland/LDD. A manuscript with the study results will be submitted to a peer-reviewed journal. All participants will be informed about the study results. The results of the study will inform clinical guidelines regarding the prophylactic treatment of children with recurrent RTIs.

TRIAL REGISTRATION NUMBER

NL7044.

The Clinical Utility of Measuring IgG Subclass Immunoglobulins During Immunological Investigation for Suspected Primary Antibody Deficiencies

Measurement of IgG subclass concentrations is a standard laboratory test run as part of a panel to investigate the suspicion of antibody deficiency. The assessment is clinically important when total IgG is within the normal age-specific reference range. The measurement is useful for diagnosis of IgG subclass deficiency, to aid the diagnosis of specific antibody deficiency, as a supporting test for the diagnosis of common variable immunodeficiency, as well as for risk stratification of patients with low IgA. The measurement of IgG subclasses may also help determine a revaccination strategy for patients and support patient management. In certain circumstances, the measurement of IgG subclasses may be used to monitor a patient’s humoral immune system. In this review, we discuss the utility of measuring IgG subclass concentrations.

Does OM-85 BV prophylaxis trigger autoimmunity in IgA deficient children?

BACKGROUND

IgA deficiency (IgAD) is the most common primary antibody deficiency. Although two-third of the cases are reported to be asymptomatic, some IgAD children may have frequent infections that urge the clinicians to search for prophylactic measures. OM-85 BV is one of these agents that is known to stimulate mucosa associated lymphoid tissue, and upregulate Th-1 response. This study was performed to determine a possible role of OM-85 BV in triggering autoimmunity in IgAD children within a four-year-follow up period.

METHODS

Sixty-three children (34 males (54%), 29 females (46%)) with sporadic IgAD and recurrent febrile infections were included. Patients were carefully screened for autoimmunity both on admission and in follow-up: Those with autoimmune features or under immunosuppressant treatment were excluded. Patients were randomly divided into two groups: Group I received bacterial lysate propylaxis (OM-85 BV) (n:37), and Group 2 received no prophylactic regimen (n:26). Development of clinical autoimmune findings or autoantibodies (anti-nuclear antibody (ANA), ANA profile (14 antigens), anti-cytoplasmic antibodies (ANCA), anti-cardiolipin antibodies IgG and IgM (aCL), rheumatoid factor (RF), direct Coombs test, anti-thyroglobulin (anti-T) and anti-thyroid microsomal antigen (anti-M)) were evaluated.

RESULTS

Mean age of the study group, age at the onset of infectious symptoms and at admission were 102.9±42.2, 27.1±24.9, and 55.2±25.1 months, respectively. Follow-up duration of the whole study group was 48.3±23.1 months. Number of infections was 6.2±2.7 per year in the whole study group. Sixteen patients (25.4%) of the whole study group showed ANA positivity in different patterns and titers. Frequency of ANA, ANCA and RF positivity was 24.3%, 5.4%, 2.7% in Group 1, and 26.9%, 11.5%, 3.8% in Group 2, respectively. Statistical comparisons revealed no significant difference between the two groups.

CONCLUSION

Significant clinical or laboratory markers for autoimmunity in follow-up were not observed between receivers or non-receivers of OM-85 BV. Frequency of ANA positivity was comparable to the previously reported values in IgAD children which was not affected by OM-85 BV usage. Possible effect of triggering autoimmunity with repeated cures of bacterial lysates needs to be further clarified. Side effects requiring the cessation of treatment were not recorded.

Increases in serum immunoglobulins to age-related normal levels in children with IgA and/or IgG subclass deficiency

Immunoglobulins (Ig) A and G subclass deficiencies are common immune system disorders which cause morbidity especially between 2 and 6 yr of age. Prognosis of these defects and therapeutic approach is unclear. The aim of the present retrospective study was to review the clinical and laboratory records of 87 children with IgA and/or IgG subclass deficiency to determine whether these patients experience changes in serum Ig concentrations during follow-up and to give more clinic and laboratory information to the families about the course of these diseases. Among 87 patients studied, the most frequent defect was partial IgA deficiency combined with IgG3 subclass deficiency (41%). The other groups were as follows; partial IgA deficiency (32%), selective IgA deficiency (8%), partial IgA combined with IgG2-G4 subclass deficiency (6%), and IgG subclass deficiency (13%). The commonest clinical presentations were recurrent upper respiratory tract infections (76%), pneumonia (14%), acute gastroenteritis (3%), urinary tractus infection (3%), sinusitis (2%), and acute otitis media (2%). Atopy was widely represented in the patients studied (24%). The number of patients who were given prophylactic treatment with benzathine penicilline, prophylactic oral antibiotic, or oral bacterial extract to prevent infections was 68 (78%). Frequency of recurrent infections decreased from 7.9 +/- 4.9 per year to 2.5 +/- 2.3 in 68 patients receiving any prophylactic regimen; however, decrease in frequency of infections did not show any significant difference between different prophylactic groups. None of the patients in the selective IgA deficiency group had reached normal serum levels of IgA. At the age of 58.3 +/- 21.4 months, 52% of patients in partial IgA deficiency group and 51% of patients in partial IgA + IgG subclass deficiency group, serum IgA increased to normal ranges. Serum IgG subclass levels increased to normal range for age in 67% of patients in partial IgA + IgG subclass deficiency group and in 30% of patients in isolated IgG subclass deficiency group. The mean age for reaching age-related normal IgG subclass levels for these patients was 69.0 +/- 14.5 months. In conclusion, findings of this study suggest that IgA and/or IgG subclass deficiency may be either progressive or reversible disorders and emphasize the value of monitoring Ig levels in affected individuals.