Into Action: Improving Access to Optimum Care for all Primary Immunodeficiency Patients

SCID and Other Inborn Errors of Immunity with Low TRECs - the Brazilian Experience

Severe combined immunodeficiency, SCID, is a pediatric emergency that represents the most critical group of inborn errors of immunity (IEI). Affected infants present with early onset life-threatening infections due to absent or non-functional T cells. Without early diagnosis and curative treatment, most die in early infancy. As most affected infants appear healthy at birth, newborn screening (NBS) is essential to identify and treat patients before the onset of symptoms. Here, we report 47 Brazilian patients investigated between 2009 and 2020 for SCID due to either a positive family history and/or clinical impression and low TRECs. Based on clinical presentation, laboratory finding, and genetic information, 24 patients were diagnosed as typical SCID, 14 as leaky SCID, and 6 as Omenn syndrome; 2 patients had non-SCID IEI, and 1 remained undefined. Disease onset median age was 2 months, but at the time of diagnosis and treatment, median ages were 6.5 and 11.5 months, respectively, revealing considerable delay which affected negatively treatment success. While overall survival was 51.1%, only 66.7% (30/45) lived long enough to undergo hematopoietic stem-cell transplantation, which was successful in 70% of cases. Forty-three of 47 (91.5%) patients underwent genetic testing, with a 65.1% success rate. Even though our patients did not come from the NBS programs, the diagnosis of SCID improved in Brazil during the pilot programs, likely due to improved medical education. However, we estimate that at least 80% of SCID cases are still missed. NBS-SCID started to be universally implemented in the city of São Paulo in May 2021, and it is our hope that other cities will follow, leading to early diagnosis and higher survival of SCID patients in Brazil.

Systematic review of literature and analysis of big data from the National Health Insurance System on primary immunodeficiencies in Korea

There are very scant data on the epidemiology of primary immunodeficiency diseases (PIDs) in Korea. Here we attempted to estimate the PID epidemiology and disease burden in Korea. A systematic review was performed of studies retrieved from the PubMed, KoreaMed, and Google Scholar databases. Studies on PIDs published in Korean or English between January 2001 and November 2018 were analyzed. The number of PID patients and the healthcare costs were estimated from Health Insurance Review and Assessment Service (HIRA) Korea data for 2017. A total of 398 PID patients were identified from 101 reports. Immunodeficiencies affecting cellular and humoral immunity were reported in 11 patients, combined immunodeficiency with associated or syndromic features in 40, predominantly antibody deficiencies in 144, diseases of immune dysregulation in 58, congenital defects of phagocytes in 104, defects in the intrinsic and innate immunity in 1, auto-inflammatory disorders in 4, complement deficiencies in 36, and phenocopies of PID in none. From the HIRA reimbursement data, a total of 1,162 outpatients and 306 inpatients were treated for 8,166 and 6,149 days, respectively. In addition, reimbursement was requested for 8,200 outpatient and 1,090 inpatient cases and $1,924,000 and $4,715,000 were reimbursed in 2017, respectively. This study systematically reviewed published studies on PID and analyzed the national open data system of the HIRA to estimate the disease burden of PID, for the first time in Korea.

National Survey about awareness of Primary Immunodeficiency Disorders among Primary Care Physicians in Saudi Arabia: Protocol and Challenges

Introduction:

Primary Health Care Centers (PHCC) are the first contact health facility to which patients in Saudi Arabia can go to seek help. Primary Immunodeficiency Disorders (PIDD) are of various types and severities, and they are associated with a delay in diagnosis. Early diagnosis of PIDD helps to improve the quality of life of affected children and prevent permanent consequences such as organ damage and disability. In this study, we present a protocol of a national survey that assesses awareness among PHCC physicians about diagnosing PIDD and the challenges associated with the execution of this protocol.

Methods:

This cross-sectional survey used stratified multistage sampling and systematic random selection of PHCC from a list of PHCC affiliated centers under the Ministry of Health (MOH) in Saudi Arabia. The survey was conducted through phone calls to the selected physicians. Data collection started in April 2020, and it is still ongoing.

Conclusion:

In Saudi Arabia, this study will provide baseline data about PHCC physicians’ levels of awareness of the diagnosis of PIDD. This will help policy-makers in designing educational courses or programs to increase awareness levels among physicians. The protocol could be used to study other health outcomes at a national level.

Evaluation of awareness about primary immunodeficiencies among physicians before and after implementation of the educational program: A longitudinal study

Increasing physicians’ awareness is one of the main ways to improve early diagnosis of rare diseases. A survey among physicians of different specialties to evaluate the knowledge about primary immunodeficiencies (PID) was conducted in 2016 and in 2019 –before and after the implementation of an educational program. We compare responses from 82 doctors who participated in the 2016 survey, and 67 doctors who have taken part in the survey in 2019: pediatricians, general practitioners / family physicians and physicians of pediatric sub specialties. The percentage of correct answers to all survey questions after the implementation of the educational program has significantly increased (79.0% in 2019 versus 58.3% in 2016, P<0.0001). This increase in the percentage of correct answers was noted among the surveyed doctors of all specialties. Particular progress was found among pediatricians, who have achieved more than 80% of correct answers. In 2019 the doctors demonstrated better knowledge on the warning signs of PID and specific features of Nijmegen breakage syndrome, DiGeorge syndrome and ataxia-telangiectasia syndrome. Thus, the implementation of an educational program improved physicians’ awareness of PIDs, and will contribute to early detection of PIDs and their medical care.

Latin American consensus on the supportive management of patients with severe combined immunodeficiency

Severe combined immunodeficiency (SCID) represents the most lethal form of primary immunodeficiency, with mortality rates of greater than 90% within the first year of life without treatment. Hematopoietic stem cell transplantation and gene therapy are the only curative treatments available, and the best-known prognostic factors for success are age at diagnosis, age at hematopoietic stem cell transplantation, and the comorbidities that develop in between. There are no evidence-based guidelines for standardized clinical care for patients with SCID during the time between diagnosis and definitive treatment, and we aim to generate a consensus management strategy on the supportive care of patients with SCID. First, we gathered available information about SCID diagnostic and therapeutic guidelines, then we developed a document including diagnostic and therapeutic interventions, and finally we submitted the interventions for expert consensus through a modified Delphi technique. Interventions are grouped in 10 topic domains, including 123 "agreed" and 38 "nonagreed" statements. This document intends to standardize supportive clinical care of patients with SCID from diagnosis to definitive treatment, reduce disease burden, and ultimately improve prognosis, particularly in countries where newborn screening for SCID is not universally available and delayed diagnosis is the rule. Our work intends to provide a tool not only for immunologists but also for primary care physicians and other specialists involved in the care of patients with SCID.

Transplantation of Hematopoietic Stem Cells for Primary Immunodeficiencies in Brazil: Challenges in Treating Rare Diseases in Developing Countries

The results of hematopoietic stem cell transplant (HSCT) for primary immunodeficiency diseases (PID) have been improving over time. Unfortunately, developing countries do not experience the same results. This first report of Brazilian experience of HSCT for PID describes the development and results in the field. We included data from transplants in 221 patients, performed at 11 centers which participated in the Brazilian collaborative group, from July 1990 to December 2015. The majority of transplants were concentrated in one center (n = 123). The median age at HSCT was 22 months, and the most common diseases were severe combined immunodeficiency (SCID) (n = 67) and Wiskott-Aldrich syndrome (WAS) (n = 67). Only 15 patients received unconditioned transplants. Cumulative incidence of GVHD grades II to IV was 23%, and GVHD grades III to IV was 10%. The 5-year overall survival was 71.6%. WAS patients had better survival compared to other diseases. Most deaths (n = 53) occurred in the first year after transplantation mainly due to infection (55%) and GVHD (13%). Although transplant for PID patients in Brazil has evolved since its beginning, we still face some challenges like delayed diagnosis and referral, severe infections before transplant, a limited number of transplant centers with expertise, and resources for more advanced techniques. Measures like newborn screening for SCID may hasten the diagnosis and ameliorate patients' conditions at the moment of transplant.

Dried Blood Spots, an Affordable Tool to Collect, Ship, and Sequence gDNA from Patients with an X-Linked Agammaglobulinemia Phenotype Residing in a Developing Country

Background

New sequencing techniques have revolutionized the identification of the molecular basis of primary immunodeficiency disorders (PID) not only by establishing a gene-based diagnosis but also by facilitating defect-specific treatment strategies, improving quality of life and survival, and allowing factual genetic counseling. Because these techniques are generally not available for physicians and their patients residing in developing countries, collaboration with overseas laboratories has been explored as a possible, albeit cumbersome, strategy. To reduce the cost of time and temperature-sensitive shipping, we selected Guthrie cards, developed for newborn screening, to collect dried blood spots (DBS), as a source of DNA that can be shipped by regular mail at minimal cost.

Method

Blood was collected and blotted onto the filter paper of Guthrie cards by completely filling three circles. We enrolled 20 male patients with presumptive X-linked agammaglobulinemia (XLA) cared for at the Vietnam National Children’s Hospital, their mothers, and several sisters for carrier analysis. DBS were stored at room temperature until ready to be shipped together, using an appropriately sized envelope, to a CLIA-certified laboratory in the US for sequencing. The protocol for Sanger sequencing was modified to account for the reduced quantity of gDNA extracted from DBS.

Result

High-quality gDNA could be extracted from every specimen. Bruton tyrosine kinase (BTK) mutations were identified in 17 of 20 patients studied, confirming the diagnosis of XLA in 85% of the study cohort. Type and location of the mutations were similar to those reported in previous reviews. The mean age when XLA was suspected clinically was 4.6 years, similar to that reported by Western countries. Two of 15 mothers, each with an affected boy, had a normal BTK sequence, suggesting gonadal mosaicism.

Conclusion

DBS collected on Guthrie cards can be shipped inexpensively by airmail across continents, providing sufficient high-quality gDNA for Sanger sequencing overseas. By using this method of collecting gDNA, we were able to confirm the diagnosis of XLA in 17 of 20 Vietnamese patients with the clinical diagnosis of agammaglobulinemia.