Renal Manifestations of IgG4-Related Disease: A Concise Review.

IgG4-related disease (IgG4-RD) is an immune-mediated disorder marked by fibro-inflammatory masses that can infiltrate multiple organ systems. Due to its relatively recent discovery and limited understanding of its pathophysiology, IgG4-related disease may be difficult to recognize and is consequently potentially underdiagnosed. Renal involvement is becoming regarded as one of the key features of this disease. To date, the most well-recognized renal complication of IgG4-related disease is tubulointerstitial nephritis, but membranous glomerulonephritis, renal masses, and retroperitoneal fibrosis have also been reported. This concise review has two objectives. First, it will briefly encapsulate the history, epidemiology, and presentation of IgG4-related disease. Second, it will examine the reported renal manifestations of IgG4-related disease, exploring the relevant histology, imaging, clinical features, and treatment considerations. This synthesis will be highly relevant for nephrologists, rheumatologists, general internists, and renal pathologists to raise awareness and help improve early recognition of IgG4-related kidney disease (IgG4-RKD).

CanVasc consensus recommendations for the use of avacopan in antineutrophil cytoplasm antibody-associated vasculitis: 2022 addendum.

OBJECTIVE: In 2020, the Canadian Vasculitis Research Network (CanVasc) published their updated recommendations for the management of ANCA-associated vasculitides (AAV). The current addendum provides further recommendations regarding the use of avacopan in AAV based on a review of newly available evidence. METHODS: An updated systematic literature review on avacopan (formerly, CCX168) using Medline, Embase, and the Cochrane Library was performed for publications up to September 2022. New recommendations were developed and categorized according to the EULAR grading levels, as done for previous CanVasc recommendations. A modified Delphi procedure and videoconferences were used to reach ≥80% consensus on the inclusion, wording and grading of each recommendation. RESULTS: Three new recommendations were developed. They focus on avacopan therapy indication and duration, as well as timely glucocorticoid tapering. CONCLUSION: These 2022 addended recommendations provide rheumatologists, nephrologists and other specialists caring for patients with AAV with guidance for the use of avacopan, based on current evidence and consensus from Canadian experts.

Mold in Foam Pillows and Mattresses: A Novel Cause of Hypersensitivity Pneumonitis.

Hypersensitivity pneumonitis (HP) is an inflammatory and/or fibrotic disease affecting the lung parenchyma and small airways. It typically results from an immune-mediated reaction provoked by an overt or occult inhaled antigen in susceptible individuals. The chronic or fibrotic form of HP has a poor prognosis, especially when no inciting antigen is identified, which occurs in up to 60% of cases. We report two cases of HP associated with exposure to mold in foam pillows and a mattress, which has not previously been reported as a risk factor for HP. Given the high prevalence of foam in pillows and mattresses, mold in foam in bedding may explain many HP cases with a previously unrecognized cause. Early identification and avoidance of foam in bedding may prevent HP progression to end-stage pulmonary fibrosis and death.

CanVasc Consensus Recommendations for the Management of Antineutrophil Cytoplasm Antibody-associated Vasculitis: 2020 Update.

OBJECTIVE: In 2015, the Canadian Vasculitis Research Network (CanVasc) created recommendations for the management of antineutrophil cytoplasm antibody (ANCA)-associated vasculitides (AAV) in Canada. The current update aims to revise existing recommendations and create additional recommendations, as needed, based on a review of new available evidence. METHODS: A needs assessment survey of CanVasc members informed questions for an updated systematic literature review (publications spanning May 2014 to September 2019) using Medline, Embase, and Cochrane. New and revised recommendations were developed and categorized according to the level of evidence and strength of each recommendation. The CanVasc working group used a 2-step modified Delphi procedure to reach > 80% consensus on the inclusion, wording, and grading of each new and revised recommendation. RESULTS: Eleven new and 16 revised recommendations were created and 12 original (2015) recommendations were retained. New and revised recommendations are discussed in detail within this document. Five original recommendations were removed, of which 4 were incorporated into the explanatory text. The supplementary material for practical use was revised to reflect the updated recommendations. CONCLUSION: The 2020 updated recommendations provide rheumatologists, nephrologists, and other specialists caring for patients with AAV in Canada with new management guidance, based on current evidence and consensus from Canadian experts.

High-Resolution Magnetic Resonance Imaging of Scalp Arteries for the Diagnosis of Giant Cell Arteritis: Results of a Prospective Cohort Study.

OBJECTIVE: To examine the concordance between high-resolution magnetic resonance imaging (MRI) of the scalp arteries and temporal artery biopsy for the diagnosis of giant cell arteritis (GCA). METHODS: We conducted a prospective cohort study of patients with suspected GCA. Participants underwent high-field 3T MRI of the scalp arteries followed by temporal artery biopsy. Arterial wall thickness and enhancement on multiplanar postcontrast T1-weighted spin-echo images were graded according to a published severity scale (range 0-3). MRI findings were compared with temporal artery biopsy results and the American College of Rheumatology (ACR) criteria for GCA. RESULTS: One hundred seventy-one patients were included in the study. Temporal artery biopsy findings were positive in 31 patients (18.1%), and MRI findings were abnormal in 60 patients (35.1%). ACR criteria were met in 137 patients (80.1%). With temporal artery biopsy as the reference test, MRI had a sensitivity of 93.6% (95% confidence interval [95% CI] 78.6-99.2) and a specificity of 77.9% (95% CI 70.1-84.4). The corresponding negative predictive value of MRI was 98.2% (95% CI 93.6-99.8) and positive predictive value was 48.3% (95% CI 35.2-61.6). CONCLUSION: In patients with suspected GCA, normal findings on scalp artery MRI are very strongly associated with negative temporal artery biopsy findings. This suggests that MRI could be used as the initial diagnostic procedure in GCA, with temporal artery biopsy being reserved for patients with abnormal MRI findings.