Heterozygous CTLA4 splice site mutation c.458-1G > C presenting with immunodeficiency and variable degree of immune dysregulation in three generation kindred of Caribbean descent

Cytotoxic T-lymphocyte-associated protein 4 (CTLA4) is an immune checkpoint, which downregulates T cell activation and T regulatory cell function. CTLA4 haploinsufficiency (CTLA4 HI) leads to T cell hyperactivation, immunodeficiency and variable degree of immune dysregulation. Furthermore, CTLA4 HI predisposes affected individuals to development of various cancers. Less well understood is the penetrance and expressivity of CTLA4 mutations. We describe five members of a single family with heterozygous CTLA4 splice site mutation c.458-1G > C, previously shown to result in CTLA-4 HI, who presented with immunodeficiency and variable degree of immune dysregulation. The host, environmental and the epigenetic factors affecting the penetrance and expressivity of CTLA4 mutations merits further investigation.

CTLA4 haploinsufficiency as a predisposition to classical Hodgkin lymphoma

Cytotoxic T-lymphocyte-associated protein 4 (CTLA4) haploinsufficiency (HI) is an immune dysregulation disorder characterized by T lymphocyte hyperactivation, and generalized lymphoproliferative and autoimmune disorders. Patients with CTLA4 haploinsufficiency are also prone to developing various malignancies. Due to the rare nature of this condition, the longitudinal evolution of CTLA4 haploinsufficiency clinical manifestations remains to be described. We report on over a decade-long course of a young adult men patient with known CTLA4 haploinsufficiency, who sequentially developed multiple autoimmune conditions along with two distinct episodes of classical Hodgkin Lymphoma (cHL) of unique histologies. Notably, the patient had serological and molecular evidence of Epstein Barr virus (EBV) infection at the time of diagnosis of both cHL. The allogeneic stem cell transplantation consolidated durable remission of cHL and CTLA-4 haploinsufficiency-related clinical manifestations, but failed to enable the patient to permanently suppress EBV viremia, which raises concerns for the development of other EBV infection-related conditions in the future. This case report adds on the current understanding of the natural clinical history of patients with CTLA4 haploinsufficiency, and their unique susceptibility to developing cHL.

Use of complement monoclonal antibody eculizumab in Shiga toxin producing Escherichia coli associated hemolytic uremic syndrome: A review of current evidence

Complement activation plays an important role in the pathogenesis of atypical hemolytic uremic syndrome. Eculizumab is a monoclonal antibody that blocks complement activity and has been approved for use in the treatment of atypical hemolytic uremic syndrome (HUS). Less well appreciated is the role of complement in Shiga toxin-induced HUS (Shiga toxin producing Escherichia coli [STEC]-HUS). To a limited extent, eculizumab has been used off label in patients with severe STEC-HUS with neurological involvement. Through a systematic search of available databases, we identified 16 reports describing the use of eculizumab in STEC-HUS (eight case reports/series, seven retrospective studies, and one prospective cohort study). All studies described its use in severe STEC-HUS with neurological or multiorgan dysfunction; none were randomized or blinded. Four studies used the control groups. Although the overall quality of evidence is low, some published studies showed positive clinical improvement after treatment with eculizumab in severe STEC-HUS with progressive neurological involvement.

Ovarian Torsion in an Adolescent with Beckwith-Wiedemann Syndrome and Unilateral Tubo-ovarian Hyperplasia

BACKGROUND

Beckwith-Wiedemann syndrome (BWS) is the most common pediatric overgrowth syndrome. BWS has a broad phenotypic presentation along with an increased propensity to develop various embryonal tumors. There are very few reported cases of gonadal hyperplasia in BWS patients in the existing literature.

CASE

We describe a 13-year-old girl with BWS who presented with an episode of abdominal pain and was found to have torsion and necrosis of a markedly hyperplastic right ovary and fallopian tube. We present a brief literature review on ovarian hyperplasia in BWS patients for which we used an online search of the databases PubMed, Embase, Ovid Medline, and Cochrane.

RESULTS AND CONCLUSION

Through an extensive literature search, we only found 3 previous reports of ovarian hyperplasia in BWS patients, all in postmortem specimens. Our case highlights a potentially important aspect of visceral organ hyperplasia in patients with BWS that could remain indolent until adolescence and might present as an abrupt-onset abdominopelvic catastrophe.