Capillary blood collection system shows promise

The BD MiniDraw, a blood collection option for nontraditional settings including pharmacies, is clinically equivalent to conventional capillary and venous collection for certain analytes and may expand access to laboratory testing (J Appl Lab Med 2025; doi: 10.1093/jalm/jfaf005).

Capillary blood sampling enables the collection of smaller volumes of blood and may benefit patients who require frequent disease monitoring. Technological advances in capillary blood collection can also be more convenient for patients. One of these capillary collection technologies — the BD MiniDraw Capillary Blood Collection System (BD MiniDraw) with the BD MiniDraw SST Capillary Blood Collection Tube (BD MiniDraw SST tube) — helps trained healthcare workers without phlebotomy experience to collect blood in nontraditional healthcare settings. In this scenario, dedicated phlebotomists or nursing professionals would be unnecessary, because pharmacists and pharmacy technicians working in retail pharmacies and patient service settings could draw blood. Specimen analysis occurs at a central laboratory.

To test the capillary collection method, three studies assessed systems and tubes in accordance with state laws. Studies one and two evaluated clinical equivalence for selected serum chemistry analytes in the BD MiniDraw, compared with currently marketed capillary and venous comparators. Study three evaluated in-tube stability for selected analytes up to 48 hours in BD MiniDraw SST tubes following storage at 2° to 8°C. For each study, the researchers prepared contrived specimens to cover medically relevant ranges and conducted testing on one general chemistry core laboratory analyzer. Biases and 95% limits within a predefined clinical acceptance limit at all medical decision levels and time points for stability demonstrated clinical equivalence.

The results also showed clinical equivalence for all analytes with BD MiniDraw versus capillary and venous comparators, except alanine aminotransferase and chloride for the venous comparator in study one. Both showed clinical equivalence at the upper limit of the reference range. The confidence interval exceeded the clinical acceptance limit at the lower limit. The studies showed in-tube stability in BD MiniDraw SST tubes up to 48 hours for all selected analytes.

Possible cause of drug-resistant pneumonia

The IncFIIK34 plasmid may be a key factor driving the global dissemination of carbapenem-resistant hypervirulent Klebsiella pneumoniae (CR-hvKp), underscoring the urgent need for better molecular surveillance of this emerging pathogen (The Lancet 2025; doi: 10.1016/j.ebiom.2025.105627). hvKp causes severe community-associated infections like liver abscesses and meningitis in otherwise healthy individuals, leading to high mortality rates. CR-hvKp shows resistance to most clinically available β-lactams, greatly limiting treatment options. The World Health Organization has reported a rising global incidence of CR-hvKp, particularly of sequence type 23. Inadequate laboratory capacity likely drives substantial underestimation of both hvKp’s and CR-hvKp’s global burden, the paper notes.

In response, the researchers analyzed CR-hvKp strains derived from canonical hvKp backgrounds and acquired a carbapenemase-encoding gene. The team identified these strains from 485 CRKp isolates in a Chinese cohort, 259 CRKp isolates from a multicenter study, and 67,631 genomes available in the GenBank sequence database. Next, the researchers selected clinical isolates harboring the IncFIIK34 KPC-2 plasmid for genome sequencing, RNA-Seq, conjugation assays, in vivo, ex vivo, and in vitro phenotypic characterization.

Analysis of clinical CR-hvKp isolates and the 414 genomes from 24 countries available in GenBank identified an IncFIIK34 KPC-2 plasmid as the prevalent KPC plasmid, detected in 25% of KPC-producing CR-hvKp across 33 countries. Compared with the epidemic IncFIIK2 KPC-2 plasmid, the IncFIIK34 KPC-2 plasmid exhibited a 100- to 1,000-fold increase in conjugation frequency and an in vitro growth advantage under meropenem challenge, likely due to the overexpression of conjugation-related genes and an increased blaKPC copy number and expression. CR-hvKp isolates and hvKp transconjugants carrying this plasmid often exhibited reduced mucoviscosity, while retaining hypervirulence in both murine models and human neutrophil assays.

The findings build upon prior evidence and underscore the emergence and prevalence of an IncFIIK34 KPC-2 plasmid in CR-hvKp. The noteworthy characteristics of this plasmid, including its high conjugation rate and elevated carbapenem resistance, highlight the critical importance of global surveillance of the IncFIIK34 KPC-2 plasmids and CR-hvKp strains.

Biomarkers may help rule out dementia

Recent research suggests that a specific group of biomarkers has the potential to rule out impending dementia in community settings (Nature Medicine 2025; doi: 10.1038/s41591-025-03605-x). Evidence on the clinical validity of blood biomarkers of Alzheimer’s disease (AD) in the general population is lacking. In response, researchers estimated the hazard and predictive performance of six AD blood biomarkers for incident all-cause and AD dementia in a cohort of 2,148 dementia-free older adults from Sweden, who were followed for up to 16 years. The biomarkers included the ratio of amyloid-β 42 to amyloid-β 40, levels of tau phosphorylated at T217 (p-tau217), tau phosphorylated at T181 (p-tau181), total tau, neurofilament light chain (NfL), and glial fibrillary acidic protein (GFAP).

In multiadjusted Cox regression models, elevated baseline levels of p-tau181, p-tau217, NfL, and GFAP were associated with a significantly increased hazard for all-cause and AD dementia, displaying a nonlinear dose-response relationship. Elevated concentrations of p-tau181, p-tau217, NfL, and GFAP demonstrated strong predictive performance (area under the curve ranging from 70.9% to 82.6%) for 10-year all-cause and AD dementia, with negative predictive values exceeding 90% and low positive predictive values (PPVs). Combining p-tau217 with NfL or GFAP further improved prediction, with PPVs reaching 43%.

These findings suggest the biomarkers may need to be combined with other biological or clinical markers to be used as screening tools, the researchers noted.