Distribution, clinical features and molecular analysis of primary immunodeficiency diseases in Chinese children: a single-center study from 2005 to 2011

Clinical and Genetic Spectrum of Inborn Errors of Immunity in a Tertiary Care Center in Southern India

OBJECTIVES

To study the incidence, clinical manifestations, and genetic spectrum of primary immunodeficiency diseases (PID)/inborn errors of immunity (IEI) in a tertiary care hospital in Southern India.

METHODS

A retrospective analysis of all patients with a clinical suspicion of PID/IEI seen at a tertiary care hospital was performed. All patients had at least one or more warning signs of PID. Serum immunoglobulin levels and other targeted investigations were performed as warranted by the clinical presentation. All families with suspected PID were counseled and offered genetic testing.

RESULTS

A total of 225 children were evaluated for PID during the study period of 6 y. Fifty-six of them did not meet the European Society of Immunodeficiencies (ESID) criteria (working definition of clinical diagnosis) and were excluded. An IEI was found in 30/49 (61.2%) patients. The most frequent reason for referral was recurrent/unusual or serious infections (28%), or cytopenia (16%). Group IV diseases of immune dysregulation was the most common category (19%), followed by group III predominant antibody deficiencies in 23/163 (14%), as per the International Union of Immunological Societies (IUIS) classification.

CONCLUSIONS

This study highlights the heterogeneity of the present cohort, the underuse of genetic tests, and efforts to provide optimal care for children with possible IEI in this center.

Diverse clinical features and diagnostic delay in monogenic inborn errors of immunity: A call for access to genetic testing

BACKGROUND

Inborn errors of immunity (IEIs) are a group of conditions affecting immune system development and function. Due to their clinical heterogeneity and lack of provider awareness, patients suffer from long diagnostic delays that increase morbidity and mortality. Next-generation sequencing facilitates earlier diagnosis and treatment of IEIs, but too often patients are unable to see the benefit of this technology due to gaps in providers' knowledge regarding which patients to test and barriers to accessing sequencing.

METHODS

Here, we provide detailed clinical phenotyping and describe the impact of genetic sequencing on a cohort of 43 patients with monogenic IEIs seen in a tertiary care center from 2014 to 2019. Data were abstracted from a chart review, and a panel of clinical immunologists were consulted on the impact of genetic sequencing on their patients.

RESULTS

We found that our patients had significant diagnostic delays, averaging 3.3 years; had diverse manifestations of immune system dysfunction; and had demonstrated highly complex medical needs, with on average 7.9 subspecialties involved in their care and 4.9 hospitalizations prior to definitive treatment. Our results also demonstrate the benefits of genetic testing, as it provided the majority of our patients with a diagnosis, and positively impacted their treatment, follow-up, and prognosis.

CONCLUSION

This paper expands the paucity of literature on genetically confirmed IEIs in North America and supports the expansion of access to genetic testing for patients with clinical features suggesting IEI, such as those presented in our cohort.

Primary immunodeficiency disease: a retrospective study of 112 Chinese children in a single tertiary care center

Background

Primary immunodeficiency disease (PID) is a disorder caused by an inherited flaw in the immune system that increases the susceptibility to infections.

Methods

In this study, 112 children with PID were diagnosed and classified based on the 2017 criteria presented by the International Union of Immunological Societies (IUIC) in a single tertiary care center from January 2013 to November 2018. We retrospectively studied the clinical features of those PID children and followed-up them as well.

Results

It was revealed that male/female ratio was 6:1. The most frequent diagnosed PID was severe combined immunodeficiency (SCID) (28.6%) and hyper-IgM (HIGM) syndrome (24.1%), followed by predominantly antibody deficiencies (17.8%). Combined immunodeficiencies with associated or syndromic features (12.5%) and congenital defects of phagocyte number, function, or both (10.7%) were less common in our center compared with SCID and HIGM syndrome. Besides, we found that 20 children (17.8%) had a positive family history of PID, and almost all cases (97.3%) had a history of recurrent infection. Recurrent respiratory tract infection was among the most common symptoms, followed by the bacterial infection of the skin and mucous membranes and diarrhea. Additionally, adverse event following immunization (AEFI) was found in 20.5% of the patients, and immune disorder was commonly observed in PID patients. In the present study, 47 patients underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT), and 2-year overall survival (OS) rate for these patients was 78.7% (37/47). It is noteworthy that OS widely differed among PID patients with different phenotypes who underwent allo-HSCT. The 2-year OS rate for SCID, HIGM syndrome, and the remaining of PID patients who underwent allo-HSCT was 14.3, 83.3, and 100%, respectively.

Conclusions

PID typically emerges at early age. Recurrent infection and serious infection were the most common clinical manifestations. Allo-HSCT is a relatively effective therapeutic strategy for PID patients.

Current status and prospects of primary immunodeficiency diseases in Asia

Primary Immunodeficiency Diseases (PIDs) are increasingly being reported across the World. Several advances have been made in the diagnostic and therapeutic research related to PIDs. With increasing awareness, the field of PIDs has rapidly evolved in Asia as well. In this review, we summarize the progress that has been made in the field of PIDs in Asian countries; major limitations and challenges faced by the clinicians working in this field in Asia; difference in spectrum of PIDs in Asia from rest of the World; current state of diagnostic and treatment facilities available in various countries in Asia and the future prospects of these diseases in the continent.

Targeted next-generation sequencing for genetic diagnosis of 160 patients with primary immunodeficiency in south China

BACKGROUND

Primary immunodeficiency disorders (PID) is a group of heterogeneous diseases mainly characterized by severe and recurrent infections and an increased susceptibility to lymphoproliferative, atopic, and autoimmune conditions. The clinical diagnosis should preferably be complemented by a genetic diagnosis. To date, PID-related reports from China seldom attempt to make a genetic test for their patients.

METHODS

Our study aimed to evaluate demographic data, clinical manifestations, and molecular diagnosis of PID patients from southern China. Moreover, by comparison with previous reports, we provide a picture of the current status of PID in mainland China. A total number of 160 pediatric PID patients (106 males and 54 females) were enrolled, and targeted next-generation sequencing was conducted using 269 PID-related genes and subsequently confirmed by Sanger sequencing and familial segregation analysis.

RESULT

The autoinflammatory disease group was the most common subcategory of PID (20%), followed by immune dysregulation (17.5%) and combined immunodeficiencies (16.2%). Antibody deficiency disorders were identified in only 11.9% of the cohort. The putative causative gene was identified in 70 patients (43.8%), and an X-linked pattern was found in 45.7% of the genetically diagnosed patients.

CONCLUSION

The current study provides the first collective study of PID phenotypes and genotypes in south China and provides a strong argument for the diagnostic application of targeted next-generation sequencing panels in patients with suspected PID.

Pediatric allergy and immunology in China

Over the past 30 years, China has enjoyed rapid economic development along with urbanization at a massive scale that the world has not experienced before. Such development has also been associated with a rapid rise in the prevalence of allergic disorders. Because of the large childhood population in the country, the burden of childhood allergic disorders has become one of the major challenges in the healthcare system. Among the Chinese centers participating in the International Study of Asthma and Allergies in Childhood, the data clearly showed a continuing rise in the prevalence of asthma, allergic rhinitis, and atopic eczema. However, the discipline of pediatric allergy in mainland China is still in its infancy due to the lack of formal training program and subspecialty certification. Clinicians and researchers are increasingly interested in providing better care for patients with allergies by establishing pediatric allergy centers in different regions of the country. Many of them have also participated in national or international collaborative projects hoping to answer the various research questions related to the discipline of pediatric allergy and immunology. It is our hope that the research findings from China will not only improve the quality of care of affected children within this country but also the millions of patients with allergies worldwide.

Clinical, immunologic, and genetic spectrum of 696 patients with combined immunodeficiency

BACKGROUND

Combined immunodeficiencies (CIDs) are diseases of defective adaptive immunity with diverse clinical phenotypes. Although CIDs are more prevalent in the Middle East than Western countries, the resources for genetic diagnosis are limited.

OBJECTIVES

This study aims to characterize the categories of patients with CIDs in Iran clinically and genetically.

METHODS

Clinical and laboratory data were obtained from 696 patients with CIDs. Patients were subdivided into those with syndromic (344 patients) and nonsyndromic (352 patients) CIDs. Targeted DNA sequencing was performed on 243 (34.9%) patients.

RESULTS

The overall diagnostic yield of the 243 sequenced patients was 77.8% (189 patients). The clinical diagnosis of hyper-IgE syndrome (P < .001), onset of disease at greater than 5 years (P = .02), and absence of multiple affected family members (P = .04) were significantly more frequent in the patients without a genetic diagnosis. An autosomal recessive disease was found in 62.9% of patients, reflecting the high rate of consanguinity in this cohort. Mutations impairing VDJ recombination and DNA repair were the most common underlying causes of CIDs. However, in patients with syndromic CIDs, autosomal recessive mutations in ataxia-telangiectasia mutated (ATM), autosomal dominant mutations in signal transducer and activator of transcription 3 (STAT3), and microdeletions in 22q11.21 were the most commonly affected genomic loci. Patients with syndromic CIDs had a significantly lower 5-year survival rate rather than those with nonsyndromic CIDs.

CONCLUSIONS

This study provides proof of principle for the application of targeted next-generation sequencing panels in countries with limited diagnostic resources. The effect of genetic diagnosis on clinical care requires continued improvements in therapeutic resources for these patients.

Data fusion of near-infrared and mid-infrared spectra for identification of rhubarb

Rhubarb has different medicinal efficacy to official rhubarb and may affect the clinical medication safety. In order to guarantee the quality of rhubarb, we established a method to distinguish unofficial rhubarbs. 52 official and unofficial rhubarb samples were analyzed using near-infrared (NIR) spectroscopy and mid-infrared (MIR) spectroscopy for classification. The feature vectors, which were selected by wavelet compression (WC) and interval partial least squares (iPLS) from NIR, MIR spectra, were fused together for identifying rhubarb samples. Partial least squares-discriminant analysis (PLS-DA), soft independent modeling of class analogies (SIMCA), support vector machine (SVM) and artificial neural network (ANN) were compared for classifying rhubarb. The use of data fusion strategies improved the classification model and allowed correct classification of all the samples.

Variable clinical phenotypes of X-linked lymphoproliferative syndrome in China: Report of five cases with three novel mutations and review of the literature

BACKGROUND

X-linked lymphoproliferative disease (XLP) is a rare life-threatening syndrome. Rapid recognition and definitive diagnosis are critical to improve the prognosis and survival of patients with XLP. Nowadays, little is known about patients with XLP in China.

METHODS

We report the characterization of five Chinese XLP patients with three novel mutations and review the literature related to this syndrome. Male patients with fulminant infectious mononucleosis (FIM), Epstein-Barr virus (EBV)-associated hemophagocytic lymphohistiocytosis (HLH) or persistent EBV viraemia were enrolled in this study. The patients' clinical features were assessed by retrieval of data from medical records. Immunological function included analysis of lymphocyte subsets and the detection of immunoglobulins G, A, M and/or E were evaluated by flow cytometry and nephelometry. Direct sequencing was used to detect SH2D1A/XIAP gene mutations.

RESULTS

Twenty-two male patients with FIM, EBV-associated HLH or persistent EBV viraemia were evaluated among 421 PID patients in our centre. Four patients had SH2D1A mutations, and one patient had an XIAP mutation. The onset age of the 5 patients range from 1month to 4years which was earlier than that in the western world. The diagnosis age was between 16months and 9years with a long diagnosis lag (1-97months). Two of them had positive family history. The clinical phenotypes varied in different patients among which two patients with FHLH and hypogammaglobulinaemia, one with hypogammaglobulinaemia, lymphoma and aplastic anaemia (AA) which is the first case with AA in China, one with hypogammaglobulinaemia only and the other one with FHLH. For immunological function, three exhibited reduced CD4/CD8 ratios. Arg55stop mutations as well as splice mutation in intron 1 were most frequently found and exon 2 was the hottest exon in China. Two patients died at the time of diagnosis for severe infection or hepatic coma. Three were alive and waiting for haematopoietic stem cell transplantation (HSCT).

CONCLUSION

For patients with severe EBV-associated HLH, hypogammaglobulinaemia, lymphoma and aplastic anaemia, possibility of XLP should be considered and if confirmed, HSCT should be performed as soon as possible.