Progressive bronchiectasis and CMC in a patient with STAT1 GOF - a rare case of primary immunodeficiency.

Bronchiestasis is a common complication developing in patients with primary immunodeficiency disorders. AD GOF STAT1 defi-ciency is characterized by CMC, repeated infections, and autoimmunity. It is the most frequently diagnosed entity in a group of PIDs with CMC. Here, we present the first Polish case of a female patient with early-onset bronchiestasis accompanied by CMC and a severe course of infections who was genetically diagnosed with AD GOF1 STAT1 mutation at the age of 15.

Successful Allogenic Stem Cell Transplantation in Patients with Inherited CARD9 Deficiency.

Autosomal recessive (AR) CARD9 (caspase recruitment domain-containing protein 9) deficiency underlies invasive infections by fungi of the ascomycete phylum in previously healthy individuals at almost any age. Although CARD9 is expressed mostly by myeloid cells, the cellular basis of fungal infections in patients with inherited CARD9 deficiency is unclear. Therapy for fungal infections is challenging, with at least 20% premature mortality. We report two unrelated patients from Brazil and Morocco with AR CARD9 deficiency, both successfully treated with hematopoietic stem cell transplantation (HSCT). From childhood onward, the patients had invasive dermatophytic disease, which persisted or recurred despite multiple courses of antifungal treatment. Sanger sequencing identified homozygous missense CARD9 variants at the same residue, c.302G>T (p.R101L) in the Brazilian patient and c.301C>T (p.R101C) in the Moroccan patient. At the ages of 25 and 44 years, respectively, they received a HSCT. The first patient received a HLA-matched HSCT from his CARD9-mutated heterozygous sister. There was 100% donor chimerism at D + 100. The other patient received a T cell-depleted haploidentical HSCT from his CARD9-mutated heterozygous brother. A second HSCT from the same donor was performed due to severe amegakaryocytic thrombocytopenia despite achieving full donor chimerism (100%). At last follow-up, more than 3 years after HSCT, both patients have achieved complete clinical remission and stopped antifungal therapy. HSCT might be a life-saving therapeutic option in patients with AR CARD9 deficiency. This observation strongly suggests that the pathogenesis of fungal infections in these patients is largely due to the disruption of leukocyte-mediated CARD9 immunity.

Autosomal dominant gain of function STAT1 mutation and severe bronchiectasis.

BACKGROUND: In a substantial number of patients with non-cystic fibrosis (CF) bronchiectasis an etiology cannot be found. Various complex immunodeficiency syndromes account for a significant portion of these patients but the mechanism elucidating the predisposition for suppurative lung disease often remains unknown. OBJECTIVE: To investigate the cause and mechanism predisposing a patient to severe bronchiectasis. METHODS: A patient presenting with severe non-CF bronchiectasis was investigated. Whole exome analysis (WES) was performed and complemented by extensive immunophenotyping. RESULTS: The genetic analysis revealed an autosomal dominant gain-of-function mutation (AD- GOF) in the signal transducer and activator of transcription 1 (STAT1) in the patient. STAT1 phosphorylation studies showed increased phosphorylation of STAT1 after stimulation with interferon γ (IFN-γ). Immunophenotyping showed normal counts of CD4 and CD8 T cells, B and NK cells, but a reduction of all memory B cells especially class switched memory B cells. Minor changes in the CD8 T cell subpopulations were seen. CONCLUSIONS: Early use of WES in the investigation of non-CF bronchiectasis was highly advantageous. The degree of impairment in class-switched memory B cells may predispose patients with AD- GOF mutations in STAT1 to suppurative sinopulmonary disease.

Disseminated histoplasmosis in chronic mucocutaneous candidiasis.

Chronic mucocutaneous candidiasis (CMC) is rarely associated with disseminated Candida, but is often associated with systemic infection secondary to other organisms [1]. A 6-year-old with CMC and disseminated histoplasmosis is presented here.