Minor Salivary Gland Biopsy in Diagnosis of Sjögren's Syndrome.

Objective: Previous studies have questioned the safety and efficacy of minor salivary gland biopsy in the diagnosis of Sjögren's syndrome, citing complications and difficulty of pathologic evaluation. This study aims to determine the rate of biopsy specimen adequacy and the risk of complications after minor salivary gland biopsy. Study Design: Case series. Setting: Single tertiary care center. Methods: We reviewed the records of all patients who underwent minor salivary gland biopsy at our institution from October 1, 2016, to September 1, 2021. Demographics, comorbidities, symptoms, and serologic results were recorded. The primary outcome was adequacy of the tissue sample. Complications of the procedure were recorded. Biopsies with at least one focus of ≥50 lymphocytes per 4-mm2 sample were considered positive. Results: We identified 110 patients who underwent minor salivary gland biopsy. Ninety-three (85%) were female, and the median age was 49.1 years (range, 18.7-80.5). Seventy-seven procedures (70%) were performed in the office setting, and 33 (30%) were performed in the operating room. Nearly all biopsy samples (n = 108, 98%) were adequate, and 33 (31%) were interpreted as positive. Four patients (4%) experienced temporary lip numbness, which resolved with conservative management. No permanent complications were reported after lip biopsy. Nineteen (58%) patients with positive biopsy results had no Sjögren's-specific antibodies. Most patients with positive biopsy results (n = 20, 61%) subsequently started immunomodulatory therapy. Conclusion: Minor salivary gland biopsy can be performed safely and effectively in both the office and the operating room. This procedure provides clinically meaningful information and can be reasonably recommended in patients suspected to have Sjögren's syndrome.

Methotrexate hampers immunogenicity to BNT162b2 mRNA COVID-19 vaccine in immune-mediated inflammatory disease.

OBJECTIVE: To investigate the humoral and cellular immune response to messenger RNA (mRNA) COVID-19 vaccines in patients with immune-mediated inflammatory diseases (IMIDs) on immunomodulatory treatment. METHODS: Established patients at New York University Langone Health with IMID (n=51) receiving the BNT162b2 mRNA vaccination were assessed at baseline and after second immunisation. Healthy subjects served as controls (n=26). IgG antibody responses to the spike protein were analysed for humoral response. Cellular immune response to SARS-CoV-2 was further analysed using high-parameter spectral flow cytometry. A second independent, validation cohort of controls (n=182) and patients with IMID (n=31) from Erlangen, Germany, were also analysed for humoral immune response. RESULTS: Although healthy subjects (n=208) and patients with IMID on biologic treatments (mostly on tumour necrosis factor blockers, n=37) demonstrate robust antibody responses (over 90%), those patients with IMID on background methotrexate (n=45) achieve an adequate response in only 62.2% of cases. Similarly, patients with IMID on methotrexate do not demonstrate an increase in CD8+ T-cell activation after vaccination. CONCLUSIONS: In two independent cohorts of patients with IMID, methotrexate, a widely used immunomodulator for the treatment of several IMIDs, adversely affected humoral and cellular immune response to COVID-19 mRNA vaccines. Although precise cut-offs for immunogenicity that correlate with vaccine efficacy are yet to be established, our findings suggest that different strategies may need to be explored in patients with IMID taking methotrexate to increase the chances of immunisation efficacy against SARS-CoV-2 as has been demonstrated for augmenting immunogenicity to other viral vaccines.

Sensitivity of fibroblast growth factor 23 measurements in tumor-induced osteomalacia.

CONTEXT: Tumor-induced osteomalacia (TIO) is a paraneoplastic syndrome of hypophosphatemia, decreased renal phosphate reabsorption, normal or low serum 1,25-dihydryxyvitamin-D concentration, myopathy, and osteomalacia. Fibroblast growth factor 23 (FGF23) is a phosphaturic protein overexpressed in tumors that cause TIO and is, at least partly, responsible for the manifestations of TIO. OBJECTIVE: The objective of this study was to determine the sensitivity of FGF23 measurements in TIO. DESIGN: FGF23 concentrations were measured on stored samples with three ELISAs. SETTING: This study was conducted at subspecialty referral centers. PATIENTS: Twenty-two patients with suspected TIO, 13 with confirmed tumors, were studied. INTERVENTIONS: There were no interventions in this study. MAIN OUTCOME MEASURE: FGF23 concentration was the main outcome measure of this study. RESULTS: Elevated FGF23 concentrations were detected using the Immunotopics C-terminal assay in 16 of 22 TIO patients (for a sensitivity of 73%), the Immunotopics Intact assay in five of 22 patients (sensitivity, 23%), and the Kainos Intact assay in 19 of 22 patients (sensitivity, 86%). In the 13 patients with confirmed tumors, the sensitivity was higher with all assays: 92% for the Immunotopics C-terminal assay, 38% for the Immunotopics Intact assay, and 100% for the Kainos assay. CONCLUSION: The Kainos Intact assay was the most sensitive, followed by the Immunotopics C-terminal assay. The findings of normal FGF23 concentrations in some patients with TIO may indicate that FGF 23 is not responsible for the hypophosphatemia in these patients or that FGF23 secretion by some tumors is partially responsive to serum phosphate. Normal FGF23 concentrations should be interpreted in relation to the serum phosphate and 1,25-dihydryxyvitamin-D concentrations.