Volume 25, Number 10—October 2019
Research
Early Diagnosis of Tularemia by Flow Cytometry, Czech Republic, 2003–20151
Figure 7

Figure 7. Comparison of time to first positive serologic test result for tularemia and time to raised CD3+/CD4–/CD8– T-cell percentage determined by flow cytometry relative to the time of symptom onset of 58 patients with probable or confirmed tularemia, Czech Republic, 2003–2015. Percentages of CD3+/CD4–/CD8– T cells >8% were considered raised. A positive serologic test result for tularemia was defined for probable cases as an antibody titer of >1:20 in any acute phase blood sample and for confirmed cases as a single antibody titer of >1:160 in any blood sample or a seroconversion from negative to positive (any titer) or a 4-fold increase in titer between acute and convalescent patient samples (agglutination test; Tularemia Diagnostic Set, Bioveta a.s., https://www.bioveta.eu). Boxes indicate interquartile ranges (IQRs), horizontal lines within boxes indicate medians, whiskers indicate range values <1.5× the IQR limits, and circles indicate outliers (i.e., values >1.5× times the IQR limits). The CD3+/CD4–/CD8– T cells increased before Francisella tularensis–specific antibody titers increased (Wilcoxon signed rank test, p<0.0001).
1Preliminary data from this study were presented at the European Congress of Clinical Microbiology and Infectious Diseases; April 9–12, 2016; Amsterdam, the Netherlands (abstract no. O367).