Antibacterial prescribing in patients presenting with COVID-19 remains discordant to rates of bacterial co-infection. Implementing diagnostic tests to exclude bacterial infection may aid reduction in antibacterial prescribing. (1) Method: A retrospective observational analysis was undertaken of all hospitalised patients with COVID-19 across a single-site NHS acute Trust (London, UK) from 1 December 2020 to 28 February 2021. Electronic patient records were used to identify patients, clinical data, and outcomes. Procalcitonin (PCT) serum assays, where available on admission, were analysed against electronic prescribing records for antibacterial prescribing to determine relationships with a negative PCT result (<25 mg/L) and antibacterial course length. (2) Results: Antibacterial agents were initiated on admission in 310/624 (49.7%) of patients presenting with COVID-19. A total of 33/74 (44.5%) patients with a negative PCT on admission had their treatment stopped within 24 h. A total of 6/49 (12.2%) patients were started on antibacterials, but a positive PCT saw their treatment stopped. Microbiologically confirmed bacterial infection was low (19/594; 3.2%) and no correlation was seen between PCT and culture positivity (p = 1). Lower mortality (15.6% vs. 31.4%; p = 0.049), length of hospital stay (7.9 days vs. 10.1 days; p = 0.044), and intensive care unit (ICU) admission (13.9% vs. 40.8%; p = 0.001) was noted among patients with low PCT. (3) Conclusions: This retrospective analysis of community acquired COVID-19 patients demonstrates the potential role of PCT in excluding bacterial co-infection. A negative PCT on admission correlates with shorter antimicrobial courses, early cessation of therapy, and predicts lower frequency of ICU admission. Low PCT may support decision making in cessation of antibacterials at the 48–72 h review.

中文翻译：

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降钙素原指导 COVID-19 住院患者抗菌处方

COVID-19 患者的抗菌处方仍与细菌合并感染率不一致。实施诊断测试以排除细菌感染可能有助于减少抗菌药物处方。(1) 方法：对 2020 年 12 月 1 日至 2021 年 2 月 28 日期间单站点 NHS 急性信托（英国伦敦）的所有 COVID-19 住院患者进行回顾性观察分析。使用电子病历来识别患者，临床数据和结果。降钙素原 (PCT) 血清检测在入院时可用，根据抗菌处方的电子处方记录进行分析，以确定与 PCT 结果阴性 (<25 mg/L) 和抗菌疗程长度的关系。(2) 结果：310/624 (49. 7%) 的 COVID-19 患者。共有 33/74 (44.5%) 入院时 PCT 阴性的患者在 24 小时内停止治疗。共有 6/49 (12.2%) 患者开始使用抗菌药物，但 PCT 阳性导致他们的治疗停止。微生物学证实的细菌感染率很低（19/594；3.2%），PCT与培养阳性之间没有相关性（p = 1）。死亡率（15.6% 对 31.4%；p = 0.049）、住院时间（7.9 天对 10.1 天；p = 0.044）和重症监护病房 (ICU) 入院（13.9% 对 40.8%；p = 0.001) 在 PCT 低的患者中被注意到。(3) 结论：这项对社区获得性 COVID-19 患者的回顾性分析证明了 PCT 在排除细菌合并感染方面的潜在作用。入院时 PCT 为阴性与较短的抗菌疗程、早期停止治疗相关，并预测入住 ICU 的频率较低。低 PCT 可能支持在 48-72 小时审查时停止抗菌药物的决策。