A beacon in the dark: COVID-19 course in CVID patients from two European countries: Different approaches, similar outcomes.

Background: CVID patients present an increased risk of prolonged SARS-CoV-2 infection and re-infection and a higher COVID-19-related morbidity and mortality compared to the general population. Since 2021, different therapeutic and prophylactic strategies have been employed in vulnerable groups (vaccination, SARS-CoV-2 monoclonal antibodies and antivirals). The impact of treatments over the last 2 years has not been explored in international studies considering the emergence of viral variants and different management between countries. Methods: A multicenter retrospective/prospective real-life study comparing the prevalence and outcomes of SARS-CoV-2 infection between a CVID cohort from four Italian Centers (IT-C) and one cohort from the Netherlands (NL-C), recruiting 773 patients. Results: 329 of 773 CVID patients were found positive for SARS-CoV-2 infection between March 1st, 2020 and September 1st 2022. The proportion of CVID patients infected was comparable in both national sub-cohorts. During all waves, chronic lung disease, "complicated" phenotype, chronic immunosuppressive treatment and cardiovascular comorbidities impacted on hospitalization, whereas risk factors for mortality were older age, chronic lung disease, and bacterial superinfections. IT-C patients were significantly more often treated, both with antivirals and mAbs, than NL-C patients. Outpatient treatment, available only in Italy, started from the Delta wave. Despite this, no significant difference was found for COVID-19 severity between the two cohorts. However, pooling together specific SARS-CoV-2 outpatient treatments (mAbs and antivirals), we found a significant effect on the risk of hospitalization starting from Delta wave. Vaccination with ≥ 3 doses shortened RT-PCR positivity, with an additional effect only in patients receiving antivirals. Conclusions: The two sub-cohorts had similar COVID-19 outcomes despite different treatment approaches. This points out that specific treatment should now be reserved for selected subgroups of CVID patients, based on pre-existing conditions.

The salivary proteome profile in patients affected by SAPHO syndrome characterized by a top-down RP-HPLC-ESI-MS platform.

SAPHO syndrome is a rare and often unrecognized disease with prominent inflammatory cutaneous and articular symptoms characterized by musculoskeletal manifestations (synovitis, hyperostosis, osteomyelitis) associated with dermatological conditions (severe acne and pustulosis). The acidic soluble fraction of whole saliva from 10 adult women affected by SAPHO syndrome and from a group of 28 healthy women was analysed by RP-HPLC-ESI-MS with the aim of discovering salivary biomarkers of the disorder. The levels of the oral proteins and peptides were correlated with clinical data. The following proteins showed a significant decreased concentration in saliva of SAPHO subjects with respect to controls: cystatin S1 and SN, histatins, the major acidic PRPs, P-C and P-B peptides. The cystatin SN abundance lowered according to the disease duration and histatins showed positive correlations with the C reactive protein. Statistical analysis performed excluding one patient with a different pattern of salivary proteins/peptides highlighted a positive relationship between cystatin S1, histatins 3, histatin 5, and the neutrophil count. Moreover, histatin 3 correlated positively with the total white cell count and negatively with the erythrocyte sedimentation rate. Levels and frequency of S100A12 protein showed a trend to increase in SAPHO patients. The high expression of this pro-inflammatory protein is probably related to the inflammatory response and to the altered neutrophil responses to functional stimuli that characterize SAPHO syndrome suggesting a possible application as a salivary biomarker.