Abstract BACKGROUND: Previous work has demonstrated that smokers have higher white blood cell counts than nonsmokers, but the effect of biochemically-confirmed smoking cessation on peripheral leukocyte counts has not been demonstrated in a large prospective study. METHODS: Subjects were healthy smokers enrolled in a trial of sustained-release bupropion for relapse prevention after smoking cessation. White blood cell (WBC) counts and absolute neutrophil counts (ANC) were measured at baseline, week 7 and week 52. Smoking status was assessed at weeks 7 and 52 by self-report and biochemically confirmed with expired air carbon monoxide levels. Multivariate analyses compared changes in WBC count and ANC between smokers who did and did not stop smoking, adjusting for treatment group, age, sex, and body mass index. RESULTS: Of 784 smokers enrolled, 461 had biochemically-confirmed tobacco abstinence after 7 weeks of bupropion; 429 were randomly assigned to receive continued bupropion or placebo until week 52. At baseline, the mean WBC count was 8.4 x 109/L (SD ±2.3) and the mean ANC was 5.3 x 109/L (SD ±1.9). The baseline WBC count and ANC were higher in smokers with greater tobacco exposure, measured by daily cigarette consumption and serum cotinine level. Between baseline and week 7, there was a significantly larger decrease in WBC count in continuously abstinent subjects compared with continuing smokers (adjusted p =.031). At 52 weeks, biochemically-confirmed continuously abstinent subjects, as compared with continuing smokers, had a greater decline from baseline in WBC count (1.2 x 109/L versus 0.1 x 109/L, p<0.001) and ANC (0.1 x 109/L versus 0.2 x 109/L, p<0.001). CONCLUSION: The WBC count and ANC of healthy smokers increase with increasing tobacco exposure. Biochemically-confirmed tobacco abstinence leads to a rapid and sustained decrease in WBC count and ANC, possibly reflecting a decrease in an underlying state of tobacco-induced inflammation.
Addressing the diagnostic gaps in pyruvate kinase deficiency: Consensus recommendations on the diagnosis of pyruvate kinase deficiency
Abstract Pyruvate kinase deficiency (PKD) is the most common enzyme defect of glycolysis and an important cause of hereditary, nonspherocytic hemolytic anemia. The disease has a worldwide geographical distribution but there are no verified data regarding its frequency. Difficulties in the diagnostic workflow and interpretation of PK enzyme assay likely play a role. By the creation of a global PKD International Working Group in 2016, involving 24 experts from 20 Centers of Expertise we studied the current gaps in the diagnosis of PKD in order to establish diagnostic guidelines. By means of a detailed survey and subsequent discussions, multiple aspects of the diagnosis of PKD were evaluated and discussed by members of Expert Centers from Europe, USA, and Asia directly involved in diagnosis. Broad consensus was reached among the Centers on many clinical and technical aspects of the diagnosis of PKD. The results of this study are here presented as recommendations for the diagnosis of PKD and used to prepare a diagnostic algorithm. This information might be helpful for other Centers to deliver timely and appropriate diagnosis and to increase awareness in PKD.