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.

A 3-Year-Old Girl with Recurrent Infections and Autoimmunity due to a STAT1 Gain-of-Function Mutation: The Expanding Clinical Presentation of Primary Immunodeficiencies.

We report a 3-year-old Peruvian girl, born to non-consanguineous parents. At the age of 8 months, she had a severe pneumonia complicated with empyema that required thoracic drainage and mechanical ventilation. Although no microorganisms were isolated, the patient recovered with broad-spectrum antibiotics. Since that date, she has presented multiple episodes of pneumonia and recurrent episodes of bronchospasm. At 1 year 5 months of age, the patient began with recurrent episodes of oropharyngeal, vaginal, and skin candidiasis, which improved transiently after using oral azole drugs. At 2.5 years of age, she was admitted with lupus-like syndrome, including serositis, hemolytic anemia, thrombocytopenia, and positive antinuclear (1:80) and dsDNA (1:10) autoantibodies. Available immunologic testing was not contributory. Imaging studies revealed bilateral ethmoidal sinusitis and mild hepatomegaly. Bone marrow analysis did not showed evidence of leukemia or myelodysplasia, while renal biopsy concluded mild mesangial proliferation. Genetic studies revealed a pathogenic heterozygous signal transducer and activator of transcription 1 gain-of-function mutation (WT/P293L). The clinical status and lung function of the patient has worsened progressively. She has not achieved an optimal response to therapy, including high-dose intravenous immunoglobulin, GM-CSF, prophylactic antibiotics and antifungal drugs, so we plan to perform hematopoietic stem cell transplantation.

Heterozygous STAT1 gain-of-function mutations underlie an unexpectedly broad clinical phenotype.

Since their discovery in patients with autosomal dominant (AD) chronic mucocutaneous candidiasis (CMC) in 2011, heterozygous STAT1 gain-of-function (GOF) mutations have increasingly been identified worldwide. The clinical spectrum associated with them needed to be delineated. We enrolled 274 patients from 167 kindreds originating from 40 countries from 5 continents. Demographic data, clinical features, immunological parameters, treatment, and outcome were recorded. The median age of the 274 patients was 22 years (range, 1-71 years); 98% of them had CMC, with a median age at onset of 1 year (range, 0-24 years). Patients often displayed bacterial (74%) infections, mostly because of Staphylococcus aureus (36%), including the respiratory tract and the skin in 47% and 28% of patients, respectively, and viral (38%) infections, mostly because of Herpesviridae (83%) and affecting the skin in 32% of patients. Invasive fungal infections (10%), mostly caused by Candida spp. (29%), and mycobacterial disease (6%) caused by Mycobacterium tuberculosis, environmental mycobacteria, or Bacille Calmette-Guérin vaccines were less common. Many patients had autoimmune manifestations (37%), including hypothyroidism (22%), type 1 diabetes (4%), blood cytopenia (4%), and systemic lupus erythematosus (2%). Invasive infections (25%), cerebral aneurysms (6%), and cancers (6%) were the strongest predictors of poor outcome. CMC persisted in 39% of the 202 patients receiving prolonged antifungal treatment. Circulating interleukin-17A-producing T-cell count was low for most (82%) but not all of the patients tested. STAT1 GOF mutations underlie AD CMC, as well as an unexpectedly wide range of other clinical features, including not only a variety of infectious and autoimmune diseases, but also cerebral aneurysms and carcinomas that confer a poor prognosis.