Development of hypogammaglobulinaemia in a patient with common variable immunodeficiency

A 3-year-old boy who developed common variable immunodeficiency was investigated for the development of hypogammaglobulinaemia. During a period of 4 years, the combined deficiency of IgA, IgG2 and IgG4 proceeded to include IgG1 and finally IgG3 and IgM. This order of isotypes of IgG subclass deficiencies corresponded to the gene order for the heavy chain constant region for immunoglobulins on chromosome 14.     

IgG subclass deficiencies in children: Facts and fiction

The chance to analyse the four IgG subclasses arose with the publication of Terry and Fahey¹. Since then, a lot of new information on the role of subclasses and their deficiency states in humans has been obtained. This review tries to analyse critically our current knowledge of subclass deficiencies in children.     

IgG2 deficiency in children with human immunodeficiency virus infection

Infection with the human immunodeficiency virus (HIV) induces a polyclonal B-cell activation. Despite elevated serum immunoglobulin levels, a significant deterioration of the antigen specific humoral immune response exists in most cases. We studied the influence of HIV infection on the serum levels of IgG subclasses in children. We investigated 76 children (aged 15 months to 18 years) with HIV-1-infection. Most children (88%) showed elevated serum immunoglobulin levels. IgA (87%) and IgM (74%) were more often above normal levels for age than IgG (60%). IgG subclass serum levels were significantly altered. The increase in total IgG was mainly due to a marked augmentation of the IgG1 fraction. In most cases IgG3 was simultaneously elevated. Ten children (13%) had very low IgG4 levels (<0.03 g/l). Out of 61 patients older than 2 years 8 (13%) had a profound IgG2 deficiency with normal or elevated total IgG. Four of them also had low IgG4 levels (<0.03 g/l). A correlation between IgG2 deficiency and HIV infection according to the Centres for Disease Control classification for acquired immunodeficiency syndrome could not be demonstrated (three patients with symptomatic and five with asymptomatic infection).     

Undetectable IgG4 in immunoprecipitation: association with repeated infections in children?

A total of 210 patients with repeated infections were screened for IgG4 deficiency. In 30 patients (14%) IgG4 was undetectable by radial immunodiffusion (<30 mg/l). Of these patients 17 (57%) were less than 2 years of age. Concomitant IgA deficiency (IgA<0.05 g/l) was demonstrated in 11 cases (37%). IgG2 serum levels below the normal range were found in 26 children. IgG4 could be demonstrated at a concentration of 0.5–29 mg/l in all 30 patients using a more sensitive enzymelinked immunosorbent assay technique. Although a highly selected group of patients was investigated, the percentage of individuals without detectable IgG4 by immunodiffusion was in the same range as reported in the literature for healthy control persons. It is thus concluded that IgG4 serum reference levels have to be defined using more sensitive methods and that the observed severe infections are more likely to be connected with low serum IgG2 and/or IgA levels than undetectable IgG4 as measured by immunodiffusion.This work was supported by a grant from the Deutsche Forschungsgemeinschaft BA 872/1-1     

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.     

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目的总结分析感染洋葱伯克霍尔德菌的X连锁慢性肉芽肿病患儿的临床特点。方法回顾分析2010年1-2月于北京儿童医院住院治疗的2例感染洋葱伯克霍尔德菌的X连锁慢性肉芽肿病患儿的临床资料。结果 2例男性患儿,分别为0.5岁和1.7岁,均经CYBB基因突变分析明确诊断为X连锁慢性肉芽肿病。1例经反复血培养、1例经反复尿培养诊断为洋葱伯克霍尔德菌感染。药敏试验结果提示均为敏感菌株。结论洋葱伯克霍尔德菌是人类机会性病原,常表现为慢性肉芽肿病。常规抗生素治疗可根除感染。预防应用复方磺胺药物对此类患儿具有保护意义。     

Phenytoin-induced IgG2 and IgG4 deficiencies in a patient with epilepsy

A five-year-old girl with epilepsy and recurrent respiratory infections was investigated for serum IgG subclass concentrations. She was diagnosed as having a combined deficiency of IgG2 and IgG4 with a decreased serum concentration of IgA and IgG3 and was given replacement therapy with i.v. immunoglobulins. Since then, she has been free from respiratory infections. After phenytoin therapy was stopped, IgG subclass deficiency improved. This case describes the further action of phenytoin on the immune system, adding IgG subclass deficiency to the list.     

Isolated IgG3 deficiency in children: to treat or not to treat? Case presentation and review of the literature

Immunoglobulin G3 (IgG3) subclass deficiency has received rather little attention thus far. In this report, the clinical and immunologic characteristics of six children with isolated IgG3 deficiency are discussed. The currently available literature on IgG3 deficiency is reviewed with specific emphasis on the peculiarities of the IgG3 subclass, the clinical relevance of IgG3 deficiency as well as the therapeutic options.     

IgG subclass deficiency in children with congenital heart disease

This study of 66 children with congenital heart disease found 26 (39%) with IgG subclass deficiency, the majority being of the IgG₄ isotype. Conventional immunoiogical assessment (IgG, IgA, IgM, T cell) revealed 21 (32%) with immunodeficiency, while inclusion of IgG subclass assessment revealed a total of 35 (53%) of the 66 children had immuno-deficiency. Children with conotruncal lesions appeared to be predisposed to immunodeficiency affecting T cells and IgG subclasses (especially IgG₄) while those with shunt and stenotic lesions had a broad spectrum of immunoglobulin deficiencies. There was significant correlation between immunodeficiency and proneness to infection in these children (p < 0.01). These results suggest that immunodeficiency is a frequent occurrence in children with congenital heart disease, and that IgG subclass measurements should be added to the diagnostic work-up.     

Haemophilus influenzae type D infection and JgG2 deficiency in a patient with chronic mucocutaneous candidiasis

A 14 year old boy with chronic mucocutaneous candidiasis and persistent pulmonary infection caused by Haemophylus influenzae and Streptococcus pneumoniae is reported. Initial bacterial culture studies showed H. influenzae type B and S. pneumoniae as causative agents. H. influenzae type D was constantly isolated from the patient's sputum. Abnormally low levels of serum immunoglobulin G2 (IgG2) found in the patient may have contributed to the pulmonary infection and H. influenzae type D may be an important causative agent in immunodeficient patients.     

Transepithelial potential difference in the bronchial system of children with chronic bronchitis and bronchial asthma.

In 45 children with chronic non-specific respiratory diseases (CNSRD), 18 with bronchial asthma and 27 with relapsing or chronic bronchitis, the transepithelial potential difference (tpd) was measured in the tracheobronchial system (bronchoscopy under general anaesthesia). The statistical variation in the tpds was highly significant. In asthmatics with significant eosinophilia in the bronchial secretions of the main bronchus we found a tpd of 26.5 (+/- 8.5) mV and in bronchitics a tpd of 18.2 (+/- 6.3) mV. This suggests that the presence or absence of eosinophils in the secretions, the products of intermediate cell metabolism or different pathogenetic processes, could be responsible for the variety of change in the tpd measured in the respiratory tract.     

Detection of parasites in children with chronic diarrhea

The aim of this study was to investigate the frequency of intestinal parasites in patients with chronic diarrhea and clarify the importance of these parasitic pathogens in such cases. A total of 60 pediatric patients with chronic diarrhea between June 2012 and October 2014 were enrolled in the study. Out of 60 stool samples, five were positive for Giardia lamblia, two, Dientamoeba fragilis, and one, Blastocystis hominis. One stool sample was positive for Entamoeba hartmanni and B. hominis, another one was positive for G. lamblia and B. hominis, another, G. lamblia and E. hartmanni and one sample was positive for Enterobius vermicularis, D. fragilis and B. hominis together. Parasitic infection, which decreases quality of life and increases susceptibility to other infections, should not be neglected, particularly in patients with chronic diarrhea. Accurate diagnosis decreases morbidity and mortality in patients with parasite infection.     

在慢性免疫性血小板减少症患儿中甄别原发性免疫缺陷症

原发性免疫缺陷症(primary immunodeficiency,PID)是一组由免疫通路上特定功能性位点突变引起免疫调控异常的遗传性疾病,免疫性血小板减少为其常见表现,且病程迁延、反复,呈现慢性免疫性血小板减少状态.而免疫性血小板减少症(immune thrombocytopenic purpura,1TP)是儿童...     

Immunoglobulin G subclass concentrations and infections in children and adolescents with severe asthma

It was the aim of this study to investigate possible dysfunctions of the humoral immune system in asthmatic children with frequent respiratory infections. Forty‐one severe asthmatics (7–15 years of age), classified according to the Second Brazilian Consensus in Asthma (1998), were divided into two groups: group I (n = 12) had recurrent respiratory infections; and group II (n = 29) were without recurrent respiratory infections. Immunoglobulin (Ig)G, IgA and IgM levels (nephelometry), and IgE (radioimmunoassay) and IgG subclasses (enzyme‐linked immunosorbent assay), were evaluated using standard methods. Asthmatics with recurrent infections presented with worse clinical evolution, an increased number of hospital admissions, and a higher need of medication than the children without recurrent infections. There were no significant differences between the mean values of IgG, IgA or IgM levels, or IgE or IgG subclasses, in patients of both groups. A complete IgA deficiency was detected in two patients of group I (one was associated with IgG subclass deficiency). Deficiency of one or more IgG subclasses was verified in eight of 12 (66%) children from group I and in 16/29 (55%) from group II. The following deficiencies were found in both groups: IgG₃ (10/41), IgG₄ (three of 41), IgG₂ (two of 41), IgG₁ (one of 41), IgG₃‐IgG₄ (four of 41), IgG₁‐IgG₃ (two of 41), and IgG₁‐IgG₃‐IgG₄ (one of 41). There were a higher proportion of children with low IgG₄ levels in group I than in group II (p = 0.01). To conclude, IgA and IgG subclass deficiencies were detected in both severely asthmatic groups, with a predominance of IgG₃ subclass deficiency. However, low IgG subclass levels appear not to be a suitable predictor of the development of infections in asthmatic children.     

Development of immunoglobulin G subclass antibodies to ovalbumin,birch and cat during the first eight years of life in atopic and non-atopic children

Immune responses to allergens in young children include both Th1- and Th2-like immunity, which may regulate the secretion of immunoglobulin (Ig) G subclass antibodies differently. The time, route and level of exposure to an allergen may be decisive with regard to whether sensitization or tolerance will ensue. To study this, we investigated the development of IgG subclass antibodies to food and inhalant allergens during childhood. The study group comprised a cohort of 96 children participating in a prospective study. IgG subclass antibodies to ovalbumin, Bet v 1 and cat dander were analyzed at birth, 6 and 18 months and 8 years by ELISA. IgG₁ and IgG₃ subclass antibodies to ovalbumin peaked at 18 months and then declined up to 8 years of age, whereas antibodies to the inhalant perennial allergen cat, but not the inhalant seasonal allergen birch, increased with age. Exposure to cat and birch tended to be associated with high antibody levels to those allergens, whereas antibody levels to ovalbumin were not related to exposure to egg. The presence of positive skin prick tests and circulating IgE antibodies correlated with high levels of IgG subclass antibody responses to the allergens. Atopic symptoms were associated with high levels of IgG subclass, particularly IgG₄, antibodies to the allergens. The difference in antibody levels between atopic and non-atopic children was most marked at 6 months for ovalbumin. For the seasonal inhalant allergen birch, the difference was apparent from 18 months, whereas a difference in antibody levels to the perennial inhalant allergen cat was already present at 6 months. In conclusion, IgG subclass antibodies to food allergens peak in early infancy and are then down-regulated, whereas antibodies to the inhalant perennial allergen cat, but not the inhalant seasonal allergen birch, increase with age. Atopy is associated with high levels of IgG subclass, particularly IgG₄, antibodies to allergens, supporting a deviation of the immune system towards Th2-like responses in atopic children.     

Hemophagocytic lymphohistiocytosis in children with chronic granulomatous disease

Hemophagocytic lymphohistiocytosis (HLH) is characterized by fever, cytopenias, splenomegaly, and hemophagocytosis by macrophages activated by high cytokine levels. Chronic granulomatous disease (CGD) is characterized by recurrent infections, hyperinflammation, and excessive cytokine release. This may predispose patients with CGD to developing HLH during an infection. We conducted a retrospective review of patients with CGD, treated at our institution between 1999 and 2008. Three out of 17 patients developed HLH. Patients with CGD may be at increased risk for developing HLH. Remission of HLH was achieved after treatment with antimicrobials, steroids, and intravenous immunoglobulin This approach to treatment appears to be effective.