Case Report: A New Gain-of-Function Mutation of STAT1 Identified in a Patient With Chronic Mucocutaneous Candidiasis and Rosacea-Like Demodicosis: An Emerging Association.

Purpose: Heterozygous missense STAT1 mutations leading to a gain of function (GOF) are the most frequent genetic cause of chronic mucocutaneous candidiasis (CMC). We describe the case of a patient presenting a new GOF mutation of STAT1 with the clinical symptoms of CMC, recurrent pneumonia, and persistent central erythema with papulopustules with ocular involvement related to rosacea-like demodicosis. Methods: Genetic analysis via targeted next-generation sequencing (NGS; NGS panel DIPAI v.1) exploring the 98 genes most frequently involved in primary immunodeficiencies, including STAT1, was performed to identify an underlying genetic defect. Results: NGS identified a novel variant of STAT1, c.884C>A (exon 10), p.T295Y, not previously described. This variant was found to be gain of function using an in vitro luciferase reporter assay. Rosacea-like demodicosis was confirmed by substantial Demodex proliferation observed via the microscopic examination of a cutaneous sample. A review of literature retrieved 20 other cases of STAT1 GOF mutations associated with early-onset rosacea-like demodicosis, most with ocular involvement. Conclusion: We describe a new STAT1 GOF mutation associated with a phenotype of CMC and rosacea-like demodicosis. Rosacea-like demodicosis appears as a novel and important clinical phenotype among patients with STAT1 GOF mutation.

[Cholangiocarcinomas developing on multiple bile duct hamartomas syndrome]. / Cholangiocarcinomes sur syndrome des microhamartomes biliaires multiples.

Two cases of cholangiocarcinoma arising in a background of multiple bile duct hamartomas are reported. In each case, the clinical and radiological investigations showed a liver tumor with no other concomitant disease. Tumors were resected, and microscopic examination revealed in one case a hilar cholangiocarcinoma, in the other case a peripheric cholangiocarcinoma, both being well-differentiated. It revealed also numerous bile duct hamartomas scattered throughout the liver. In one case, some bile duct hamartomas showed a gradual morphologic transition from benign to dysplastic and neoplastic epithelium. Patients with multiple bile duct hamartomas may have an increased risk of developing cholangiocarcinomas.

A case of aortic and mitral valve involvement in granulomatosis with polyangiitis.

Granulomatosis with polyangiitis (GPA) (Wegener's) is a necrotizing systemic vasculitis of the small-sized blood vessels, affecting kidneys, lungs, upper respiratory tract and skin. Cardiac valvular involvement is an uncommon manifestation of GPA. We report the case of a 60-year-old woman with arthritis and lung nodules due to GPA without antineutrophil cytoplasmic antibodies (ANCA) at time of diagnosis. Remission was obtained with cyclophosphamide and corticosteroid. Azathioprine was then prescribed for 2years. Four years later, she developed severe inflammatory aortic and mitral valvular involvement characterized by GPA typical histopathological valvular lesions. Search for ANCA was positive at this time (anti-myeloperoxidase). Cardiac valvular involvement is a rare and potentially fatal complication of GPA and may misleadingly suggest infectious endocarditis. A review of literature revealed few cases of histologically well-documented cardiac valvular involvement in GPA. Pathologists should be aware of valvular heart diseases in GPA, which usually comprise valvular necrotic lesions without any microbial agents.