Department of Family and Community Medicine, Baylor College of Medicine, Houston, TX, USA.
Department of Family and Community Medicine, Baylor College of Medicine, Houston, TX, USA; Center for Innovations in Quality, Effectiveness and Safety (IQuESt), Michael E. DeBakey Veterans Affairs Medical Center, Houston, TX, USA.
Int J Nurs Stud. 2022 Oct;134:104325. doi: 10.1016/j.ijnurstu.2022.104325. Epub 2022 Jul 11.
Antimicrobial resistance is a global health threat. To slow resistance and preserve antibiotics, stewardship interventions are increasingly promoted and mandated. Urine cultures are the most common microbiological test in the outpatient setting. Contamination most likely occurs during urine collection from surrounding vaginal, perineal, and epidermal flora. Sample contamination can lead to incorrect diagnosis, unnecessary or inappropriate treatment, poor patient outcomes, and higher costs. Therefore, ensuring proper collection of urinary samples serves as a prime diagnostic stewardship target, one that international nursing societies increasingly endorse as an opportunity for nurse involvement.
Determine the prevalence, predictors, and antibiotic prescribing associated with contaminated urine cultures in primary care clinics.
Cross-sectional study.
Two adult safety-net clinics in Houston, Texas.
1265 clinical encounters among 1114 primary care patients.
We reviewed charts from office visits among patients who had a urine culture ordered between November 2018 and March 2020. Patient demographics, culture results and prescription orders were captured for each visit. Culture results were defined as no growth, contaminated (i.e., mixed flora, non-uropathogens, or ≥3 bacterial species isolated), or low-count (10-10 colony forming units (CFU)/mL) or high-count (>10 CFU/mL) uropathogen-positive. We performed multinomial logistic regression to identify predictors independently associated with contaminated cultures.
Our study evaluated 1265 cultures from 1114 patients that were primarily female (84 %), of Hispanic/Latino (74.4 %) or Black/African American (18.9 %) race/ethnicity with a mean age of 43 years. Out of 1265 urine cultures, 264 (20.9 %) had no growth, 694 (54.9 %) were contaminated, 159 (12.6 %) were low-count positive, and 148 (11.7 %) were high-count positive. Female sex, pregnancy, and obesity were associated with contaminated cultures (multinomial adjusted odds ratios: 15.89, 14.34, 1.93, respectively; 95 % confidence intervals: 10.25-24.61, 8.03-25.61, 1.32-2.81, respectively). Antibiotic prescribing was significantly higher among symptomatic patients with contaminated cultures compared to those with no growth.
Urine culture contamination occurred frequently in our clinics, and obesity, female sex and pregnancy were independent risk factors for contamination. The association of pregnancy and contamination is particularly concerning as pregnant females are routinely screened and treated for asymptomatic bacteriuria in the United States. Culture contamination may obscure underlying uropathogens, leading to pyelonephritis or potential neonatal infection if untreated. Conversely, overtreatment of false positive bacteriuria could lead to adverse effects from antibiotics and increased risk for antibiotic resistance. As nurses play a prominent role in patient education, diagnostic stewardship interventions may want to utilize nurses' educational capabilities to improve urine culture collection.
55 % of urine cultures collected in primary care clinics were contaminated, revealing a major opportunity for nurse-driven diagnostic stewardship interventions.
抗菌药物耐药性是一个全球性的健康威胁。为了减缓耐药性的产生并保护抗生素，管理干预措施越来越受到重视和要求。尿液培养是门诊环境中最常见的微生物学检测。污染最有可能发生在从周围阴道、会阴和表皮菌群中采集尿液时。样本污染可能导致误诊、不必要或不适当的治疗、不良的患者结局和更高的成本。因此，确保尿液样本的正确采集是一个主要的诊断管理目标，国际护理学会越来越多地认可这是护士参与的机会。
确定初级保健诊所中尿液培养污染的流行率、预测因素和抗生素处方相关情况。
横断面研究。
德克萨斯州休斯顿的两家成人安全网诊所。
1114 名初级保健患者中有 1265 次临床就诊。
我们回顾了 2018 年 11 月至 2020 年 3 月期间在办公室就诊时开具尿液培养的患者的图表。记录了每位患者的患者人口统计学数据、培养结果和处方医嘱。培养结果定义为无生长、污染（即混合菌群、非尿路病原体或分离出≥3 种细菌物种）、低计数（10-10 个菌落形成单位（CFU）/毫升）或高计数（>10 CFU/mL）尿路病原体阳性。我们进行了多变量逻辑回归，以确定与污染培养物独立相关的预测因素。
我们的研究评估了 1114 名患者的 1265 个培养物，其中主要为女性（84%），主要为西班牙裔/拉丁裔（74.4%）或黑人和非裔美国人（18.9%），平均年龄为 43 岁。在 1265 个尿液培养物中，264 个（20.9%）无生长，694 个（54.9%）污染，159 个（12.6%）低计数阳性，148 个（11.7%）高计数阳性。女性、怀孕和肥胖与污染培养物相关（多变量调整后的优势比：15.89、14.34、1.93；95%置信区间：10.25-24.61、8.03-25.61、1.32-2.81）。与无生长相比，有症状的污染培养物患者的抗生素处方明显更高。
我们的诊所经常发生尿液培养污染，肥胖、女性和怀孕是污染的独立危险因素。怀孕和污染的关联尤其令人担忧，因为在美国，孕妇通常会接受无症状菌尿的常规筛查和治疗。培养物污染可能会掩盖潜在的尿路病原体，如果不治疗，可能会导致肾盂肾炎或潜在的新生儿感染。相反，对假阳性菌尿的过度治疗可能会导致抗生素的不良反应和抗生素耐药性的风险增加。由于护士在患者教育中发挥着重要作用，诊断管理干预措施可能希望利用护士的教育能力来改善尿液培养采集。
初级保健诊所中采集的尿液培养物有 55%受到污染，这为护士主导的诊断管理干预提供了一个重要机会。
