BackgroundSevere combined immunodeficiency (SCID) is fatal unless treated with hematopoietic stem cell transplant. Delay in diagnosis is common without newborn screening. Family history of infant death due to infection or known SCID (FH) has been associated with earlier diagnosis.ObjectiveThe aim of this study was to identify the clinical features that affect age at diagnosis (AD) and time to the diagnosis of SCID.MethodsFrom 2005 to 2016, 147 SCID patients were referred to the Asian Primary Immunodeficiency Network. Patients with genetic diagnosis, age at presentation (AP), and AD were selected for study.ResultsA total of 88 different SCID gene mutations were identified in 94 patients, including 49 IL2RG mutations, 12 RAG1 mutations, 8 RAG2 mutations, 7 JAK3 mutations, 4 DCLRE1C mutations, 4 IL7R mutations, 2 RFXANK mutations, and 2 ADA mutations. A total of 29 mutations were previously unreported. Eighty-three of the 94 patients fulfilled the selection criteria. Their median AD was 4 months, and the time to diagnosis was 2 months. The commonest SCID was X-linked (n = 57). A total of 29 patients had a positive FH. Candidiasis (n = 27) and bacillus Calmette–Guérin (BCG) vaccine infection (n = 19) were the commonest infections. The median age for candidiasis and BCG infection documented were 3 months and 4 months, respectively. The median absolute lymphocyte count (ALC) was 1.05 × 109/L with over 88% patients below 3 × 109/L. Positive FH was associated with earlier AP by 1 month (p = 0.002) and diagnosis by 2 months (p = 0.008), but not shorter time to diagnosis (p = 0.494). Candidiasis was associated with later AD by 2 months (p = 0.008) and longer time to diagnosis by 0.55 months (p = 0.003). BCG infections were not associated with age or time to diagnosis.ConclusionFH was useful to aid earlier diagnosis but was overlooked by clinicians and not by parents. Similarly, typical clinical features of SCID were not recognized by clinicians to shorten the time to diagnosis. We suggest that lymphocyte subset should be performed for any infant with one or more of the following four clinical features: FH, candidiasis, BCG infections, and ALC below 3 × 109/L.

To address inborn errors of immunity (IEI) which were underdiagnosed in resource-limited regions, our centre developed and offered free genetic testing for the most common IEI by Sanger sequencing (SS) since 2001. With the establishment of The Asian Primary Immunodeficiency (APID) Network in 2009, the awareness and definitive diagnosis of IEI were further improved with collaboration among centres caring for IEI patients from East and Southeast Asia. We also started to use whole exome sequencing (WES) for undiagnosed cases and further extended our collaboration with centres from South Asia and Africa. With the increased use of Next Generation Sequencing (NGS), we have shifted our diagnostic practice from SS to WES. However, SS was still one of the key diagnostic tools for IEI for the past two decades. Our centre has performed 2,024 IEI SS genetic tests, with in-house protocol designed specifically for 84 genes, in 1,376 patients with 744 identified to have disease-causing mutations (54.1%). The high diagnostic rate after just one round of targeted gene SS for each of the 5 common IEI (X-linked agammaglobulinemia (XLA) 77.4%, Wiskott–Aldrich syndrome (WAS) 69.2%, X-linked chronic granulomatous disease (XCGD) 59.5%, X-linked severe combined immunodeficiency (XSCID) 51.1%, and X-linked hyper-IgM syndrome (HIGM1) 58.1%) demonstrated targeted gene SS should remain the first-tier genetic test for the 5 common X-linked IEI.

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Severe combined immunodeficiency includes inherited diseases with impairment of T cells development, often associated with profound defects of B and/or NK cells differentiation. Rotavirus infection is responsible for severe acute gastroenteritis and over 400,000 deaths a year in children aged < 5 years, especially in low and middle-income countries. We report a nine-month-old girl presented with failure to thrive left axillary lymphadenitis post-BCG-vaccination, persistent, nonvaccine-associated rotavirus gastroenteritis. An immune evaluation revealed absent T lymphocytes, B lymphocytes, normal NK cells with genetic testing confirmed RAG2 severe combined immunodeficiency. Rotavirus gastroenteritis persisted despite the administration of oral immunoglobulin pre-transplantation. The patient was treated by a haploidentical transplant -from mother as a donor using CD3/CD45RA+ depletion kit, CliniMACs system (Miltenyi). The first transplant was performed without conditioning. One month post-transplant, rotavirus was cleared. The second transplant was performed three months later, with myeloablative conditioning (Bu-Flu-rATG). Neutrophils engrafted on day +10 post-transplant, platelet engrafted on day +45. Whole blood chimerism on day +28 post 2nd transplant was 100%. Serum IgG level has been normalized without IVIG infusion three months post 2nd transplant.

BackgroundStevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) is a rare and life-threatening disease of the skin and mucosal surfaces. Although gastrointestinal manifestations in adults are potential prognostic factors for disease severity, there are limited data on such cases and their standard management in the pediatric population.Case PresentationWe herein report the case of an 8-year-old girl with a 1-year history of epilepsy, who presented with bilateral conjunctivitis and progressively widespread bullous, and pruritic eruption based on erythematous skin after administration of carbamazepine. A diagnosis of carbamazepine-induced TEN was made, and the drug was immediately discontinued. The result of genetic screening showed that the patient was positive for the HLA-B*15:02 allele. Then, her condition got worse by developing gastrointestinal involvement, including hematemesis and severe watery bloody diarrhea. A combination of the intravenous immunoglobulin and the appropriate dose of systemic steroids have contributed to a favorable outcome in this case. Multidisciplinary care of mucocutaneous involvement, supplemental nutrition, and fluid replacement was also critically warranted. This report aims to contribute to the current literature on TEN-related gastrointestinal manifestations in pediatrics and highlights the need for further investigations in determining the optimal treatment in such cases.ConclusionIn conclusion, we reported the successful treatment of TEN-related gastrointestinal manifestations in a pediatric patient, which should be critically considered in patients with SJS/TEN. Since it may significantly contribute to the poor prognosis of the illness, further investigations in determining standard management in such cases are necessary.