Replication Data for: Impact of Hematocrit and Storage Temperature on Dried Blood Samples for Serological Study of Diphtheria, Tetanus, and Pertussis

Resumo

Dried blood spots (DBS) offer a convenient alternative to serum/plasma for conducting serolog-ical and molecular studies on various pathogens. Sixty-four blood samples were collected by venipuncture and spotted onto Whatman™ 903 cards to evaluate the utility of DBS and the effect of the storage temperature for 4 months after sample collection to carry out serological diagno-sis. An automated chemiluminescent immunoassay was used to investigate diphtheria, tetanus, and pertussis IgG levels from both DBS and plasma samples. An optimal cut-off value for DBS was calculated to improve the performance of diphtheria and tetanus serological markers in DBS, achieving high sensitivity (95% and 98%, respectively) and specificity (91.7% and 92.3%, respectively). No protection against pertussis was found in the population studied. The correla-tion observed between the plasma and the DBS processed after sample collection was high (0.967–0.970) for all antibodies studied except pertussis (0.753), both considering hematocrit be-fore sample elution or not. The correlation between DBS and plasma for diphtheria and tetanus remained strong following a 4-month delay in DBS processing at 4 °C (0.925-0.964) and -20 °C (0.924–0.966), with only a minor decrease observed for diphtheria at room temperature (0.889), while maintaining a strong correlation for tetanus (0.960). For pertussis, the correlation between DBS and plasma was drastically reduced after delaying its processing for 4 months at any tem-perature. To summarize, hematocrit does not affect the processing of DBS in the study of sero-logical markers of diphtheria, tetanus and pertussis. DBS stability for serological diagnosis of diphtheria and tetanus is adequate when samples are stored at −20 °C, 4 °C and even at room temperature, for a period of 4 months. Pertussis serological marker does not appear to remain stable after 4 months, even when the DBS is stored frozen at -20 °C.