Parvovirus B19 infection with rheumatologic manifestations: results from a multicentre Italian study

To characterise the clinical spectrum of adult parvovirus B19 (B19V) infection referred for rheumatologic evaluation and to identify clinical predictors of arthritis resolution.

We conducted a multicentre retrospective study across nine Italian rheumatology units during the 2023-2024 post-pandemic resurgence of B19V infection. Clinical, therapeutic, and follow-up data were systematically collected using a standardised REDCap platform.

We enrolled 71 patients (median age 43 years; 72% female), 85% with a confirmed diagnosis. Most reported recent household exposure. Joint involvement was nearly universal (96%), predominantly oligoarticular, and often affected large joints, mimicking early inflammatory arthritis. Fever (65%) and skin manifestations (61%) were frequent. In addition to typical exanthems, 9 patients displayed a distinctive purpuric rash confined to the pretibial region, sparing ankles and feet - a potentially distinctive feature of to B19V infection. Symptom resolution occurred in 87% of cases, usually within one month. Glucocorticoid use was independently associated with - but not proven to cause - faster resolution in Cox regression (HR 0.53; 95% CI: 0.31-0.90; p=0.020), though this finding may reflect indication bias. No other clinical or serological predictors emerged.

This study provides the largest systematically collected multicentre cohort of adults with B19V infection referred to rheumatology during the post-pandemic European outbreak. Our findings expand the clinical spectrum of B19V arthritis and highlight distinctive skin patterns that may aid differential diagnosis during epidemic waves.