Background: Infections in hand surgery represent a clinically relevant complication, particularly in trauma-related procedures and in the presence of internal fixation devices. Data specifically addressing microbiological profiles and antimicrobial resistance patterns in hand surgery remain limited. Methods: A monocentric retrospective observational study was conducted, including 72 patients treated for hand surgery infections between January 2024 and June 2025. Microbiological isolates and antimicrobial susceptibility profiles were analyzed and stratified according to the clinical scenario, including trauma-related infections and infections associated with internal fixation devices. Monomicrobial and polymicrobial infections were evaluated separately. Results: Trauma-related infections accounted for 77.8% of cases, of which 64.3% were monomicrobial and 35.7% polymicrobial. Monomicrobial trauma-related infections were predominantly caused by Staphylococcus aureus, with methicillin resistance detected in 25.0% of cases. Polymicrobial trauma-related infections showed greater microbiological complexity but limited antimicrobial resistance. Infections associated with internal fixation devices represented 22.2% of cases and demonstrated a higher proportion of polymicrobial infections. Across all subgroups, no extended-spectrum beta-lactamase–producing Enterobacterales or carbapenem-resistant organisms were identified. Conclusions: This study fills an important evidence gap by characterizing pathogens and antimicrobial resistance in a dedicated hand surgery cohort, an area where published microbiological data remain limited compared with other orthopedic subspecialties. Hand surgery infections exhibit distinct microbiological and resistance profiles depending on the clinical scenario and microbial complexity. Despite frequent polymicrobial involvement, high-level antimicrobial resistance remains uncommon, supporting the value of local microbiological surveillance to guide empirical therapy.

Background/Objectives: Antinuclear antibody testing by indirect immunofluorescence on HEp-2 cells (ANA-IIF) remains the reference test for systemic autoimmune rheumatic diseases (SARD). However, complete serological characterization requires integration with extractable nuclear antigen (ENA) screening, antigen-specific solid-phase assays (SPA), and confirmatory indirect immunofluorescence (IIF) tests. This study aimed to: (1) quantify real-world serological pathway incompleteness in ANA testing performed outside a structured reflex strategy; (2) compare simulated stepwise and upfront parallel reflex approaches in terms of serological yield, laboratory workload, and costs. Methods: We retrospectively analyzed 2207 consecutive patients referred for ANA-IIF testing between July 2025 and April 2026. Serological incompleteness was defined as non-completion of the predefined Regione Lombardia reflex framework. A fully characterized subgroup of 514 patients, defined by complete reflex-serological assessment, was used to compare a stepwise strategy, in which ANA-IIF positivity triggered downstream testing, with an upfront parallel strategy, in which ANA-IIF, ENA screening, and anti-double-stranded DNA (anti-dsDNA) testing were performed upfront. Results: ANA-IIF was positive in 913/2207 patients (41.4%). Overall, 508 patients (23.0%) had at least one missing follow-up assay expected under the reflex framework. In the fully characterized subgroup, the upfront parallel strategy increased the number of patients with at least one fully characterized autoantibody finding from 15 to 22 (+1.4%), but required 657 additional tests and an estimated incremental cost of approximately €2592. Conclusions: ANA-IIF testing outside a structured reflex pathway frequently resulted in incomplete serological assessment. Although the upfront parallel strategy increased serological yield, it required substantially greater laboratory workload and costs than the stepwise approach. Further studies are needed to define the optimal balance between serological yield, clinical relevance, and cost-effectiveness.

To investigate factors associated with multidrug resistance (MDR) in diabetes-related foot infections (DFIs), focusing on polymicrobial infection and glycated hemoglobin (HbA1c). This retrospective single-center study included culture-positive deep-tissue biopsy specimens collected during 2025. Consecutive positive biopsies from the same patient were grouped into episodes when successive samples were obtained ≤7 days apart. MDR was assessed using organism-specific antimicrobial categories, counting resistant results and excluding expected resistance phenotypes. Logistic regression used patient-clustered robust standard errors. HbA1c was evaluated in a secondary model restricted to measurements within ±30 days of sampling. The 191 culture-positive biopsies yielded 175 episodes from 150 patients; 43 episodes (24.6%) were polymicrobial. The most frequently recovered species were Staphylococcus aureus (35.4% of episodes), Pseudomonas aeruginosa (20.6%) and Enterococcus faecalis (14.9%). Among 157 MDR-evaluable episodes, 49 (31.2%) were MDR-positive. MDR occurred in 46.5% of polymicrobial versus 25.4% of monomicrobial episodes (crude OR 2.55; p = 0.020). Polymicrobial infection remained associated with MDR after adjustment for Gram-negative involvement, age and sex (aOR 4.52, 95% CI 1.91–10.72). In the HbA1c-adjusted model (94 episodes; 85 patients), polymicrobial infection remained associated with MDR (aOR 4.04, 95% CI 1.38–11.84), whereas HbA1c was not significantly associated with MDR (aOR 0.91 per 1% increase, 95% CI 0.69–1.20). Polymicrobial infection was associated with MDR, although unmeasured clinical confounding limits interpretation. The HbA1c findings remain inconclusive because of limited precision. These associations require confirmation in larger studies incorporating detailed clinical exposures and wound characteristics.