Characterization of the adherence to hemoculture-guided monotherapy for the treatment of neonatal infections in a teaching maternity hospital

Abstract

Objective: To characterize positive blood cultures and medical adherence to blood culture-guided antimicrobial monotherapy, as well as factors associated with this practice, in a neonatal intensive care unit (NICU). Methods: A cross-sectional retrospective study carried out using notification forms of infections related to healthcare in newborns hospitalized with positive blood cultures from January to December 2019, in the NICU of a teaching maternity hospital from Fortaleza, Brazil. Demographic and clinical data of the newborns were collected, as well as antimicrobials used and blood culture result. Adherence to monotherapy was considered when there was prescription of only one antimicrobial agent sensitive to the isolated microorganism. Data analysis was performed using Excel® and GraphPad Prism softwares. Results: 62 positive blood cultures from 48 newborns were included. Of these, the majority were female (54,2%), extremely preterm (29,2%) and had extremely low birth weight (35,4%). Gram-positive bacteria (59,7%) were the most isolated, mainly Staphylococcus epidermidis (54,1%) and Staphylococcus haemolyticus (18,9%). Vancomycin (21%) was the most prescribed antimicrobial, followed by oxacillin (19,4%). Regarding adherence, it was observed that 53.2% of prescriptions did not adhere to monotherapy. On the other hand, adherence to monotherapy was observed in 53.3% of hospital discharge cases. Adherence to monotherapy was more frequent after detection of fungi (75%) and Gram-negative bacteria (66,7%) than after detection of Gram-positive bacteria (32,4%). Furthermore, infections with Gram-negative bacteria were significantly associated with adherence to monotherapy (p = 0.03, relative risk = 1.82), while infections with Gram-positive bacteria were significantly associated with non-adherence to monotherapy (p = 0.01, relative risk = 0.48). No statistically significant associations were found between the other analyzed variants. Conclusion: Adherence to antimicrobial monotherapy guided by blood culture occurred in less than half of the therapies in preterm and low birth weight newborns. Gram positive bacteria are related to non-adherence to monotherapy. There were also high prevalence rates of vancomycin prescription and of Staphylococcus spp (mostly resistant to oxacillin).