Blood Culture-Based Classification of Early Bacterial Bloodstream Infection After Autologous Hematopoietic Stem Cell Transplantation: A Retrospective Cohort Study

Microorganisms, cilt.14, sa.11, ss.2459, 2026 (SCI-Expanded)

Yayın Türü: Makale / Tam Makale
Cilt numarası: 14 Sayı: 11
Basım Tarihi: 2026
Doi Numarası: 10.3390/microorganisms14112459
Dergi Adı: Microorganisms
Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED)
Sayfa Sayıları: ss.2459
İnönü Üniversitesi Adresli: Evet

Estimates of early bacterial bloodstream infection (BSI) after autologous hematopoietic

stem cell transplantation (HSCT) depend on the classification of common commensals. We

examined the sensitivity of BSI frequency and microbiology to three operational definitions.

This retrospective single-center cohort comprised 161 autologous transplant episodes in

158 patients from September 2015 to February 2026. The endpoint covered day 0–30. A

permissive rule counted any bacterial growth. The primary definition excluded CoNSonly

episodes classified as contamination following retrospective review of blood culture

results and clinical records. A restrictive definition additionally excluded episodes with

sole viridans-group or unspeciated streptococci or Corynebacterium. Formal adjudication

according to the full National Healthcare Safety Network surveillance criteria was not

performed. Regression and survival analyses were exploratory. The proportions meeting

the permissive, primary, and restrictive endpoints were 56.5% (91/161), 23.6% (38/161; 95%

confidence interval 17.3–30.9), and 21.1% (34/161), respectively. The primary definition included

40 isolates, of which 27 (67.5%) were Gram-negative and 21 (52.5%) were Escherichia

coli. Gram-positive isolates predominated under the permissive rule (71.0%). Exploratory

regression estimates were imprecise. In the day-30 landmark survival analysis, the operational

BSI classification was inversely associated with subsequent mortality; however, this

finding was based on only four deaths in the BSI-classified group and remained vulnerable

to survivor selection, residual confounding, and exposure misclassification. Reported BSI

frequency and organism distribution were sensitive to commensal classification. Explicit

operational definitions, retrospective clinical assessment of CoNS isolates, and sensitivity

analyses aid interpretation; however, the absence of standardized surveillance adjudication

limits the estimation of true BSI incidence. The survival findings require cautious,

noncausal interpretation.