We identified 3 patients with de novo RAC2[E62K] mutations resulting in severe T- and B-cell lymphopenia, myeloid dysfunction, and recurrent respiratory infections.
We describe 1 patient with cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) haploinsufficiency who had recurrent enhancing brain lesions, nodular pulmonary infiltrates, hepatosplenomegaly, immune cytopenias, as well as progressive hypogammaglobulinemia and lymphopenia.
Our data should raise physicians' awareness of [1] lymphoma proneness of STK4 deficient patients even in the absence of EBV infection and [2] possibly underlying STK4 deficiency in pediatric patients with a history of recurrent infections, CD4 lymphopenia and lymphoma and unknown genetic make-up.
Sixty-four children were recalled for follow-up due to low TREC and/or KREC levels, and three patients with immunodeficiency (Artemis-SCID, ATM, and an as yet unclassified T cell lymphopenia/hypogammaglobulinemia) were identified.
Therefore, efficient Cxcr4 desensitization is critical for lymphoid differentiation of HSPCs, and its impairment is a key mechanism underpinning the lymphopenia observed in mice and likely in WS patients.
We report the first case of a child with STK4-mutated CD4+ lymphocytopenia who developed Epstein-Barr virus associated MALT lymphoma arising in the salivary gland.
Our experience suggests that a diagnosis of congenital neutropenia due to G6PC3 may not be as straightforward in such patients with combined lymphopenia and thrombocytopenia.
These findings identify the genomic instability associated with V(D)J recombination at the TCRδ locus as the molecular origin of both lymphocytopenia and the signature t(12;14) translocations associated with ATM deficiency.
Here we investigate the findings of T cell lymphopenia and inflammatory bowel disease in a child with G6PC3 deficiency due to compound heterozygous mutations in intron 3 (c.IVS3-1 G>A) and exon 6 (c.G778G/C; p.Gly260/Arg).
The causes of the T-cell lymphopenia included DiGeorge syndrome (n = 2), idiopathic T-cell lymphopenia (n = 2), extravascular extravasation of lymphocytes (n = 3), and a Rac2 mutation (n = 1).
The purpose of this review was to critically analyse the literature on invasive fungal infections (IFIs) occurring in association with mAbs and fusion proteins other than tumour necrosis alpha (TNF-α) inhibitors, including therapeutics modulating T-cell-mediated pathologies (muromonab, abatacept, belatacept, ipilimumab, basiliximab, daclizumab), inducing lymphopenia (alemtuzumab), depleting CD20+ B cells (rituximab) and interfering with various targets (anakinra, natalizumab, blodalumab, ixekizumab and others) with a focus on children, and to provide a framework of evaluating the risk for IFIs in this population.
Patients with heterozygous STAT1 gain-of-function (GOF) mutations usually present with chronic mucocutaneous candidiasis (CMC) but may also experience bacterial and viral infections, autoimmune manifestations, lymphopenia, cerebral aneurysms, and increased risk to develop tumors.
Mutations in the moesin gene in humans are associated with primary immunodeficiency with profound lymphopenia, and moesin-deficient mice exhibit a similar lymphopenia phenotype.