Warnke Philipp, Warning Liesa, Podbielski Andreas
Institute of Medical Microbiology, Virology, and Hygiene, Rostock University Hospital, Rostock, Germany.
PLoS One. 2014 Jul 10;9(7):e102215. doi: 10.1371/journal.pone.0102215. eCollection 2014.
Swabs are widely used to collect samples for microbiological analyses from various clinical settings. They vary by material, size, and structure of the tip. This study investigates the uptake and release capacities for liquid and bacteria.
Five swabs were analyzed for their uptake and release capacities of Staphylococcus aureus and Staphylococcus epidermidis suspensions. Two approaches were investigated providing volume-restricted and unrestricted amounts of bacterial suspensions to mimic various clinical situations. Volume and bacterial uptake and release were measured in milligrams and by counting colony forming units (CFU), respectively.
Volume uptake and release in the unrestricted setting varied highly significant between 239.6 mg and 88.7 mg (p<0.001) and between 65.2 mg and 2.2 mg (p<0.001), respectively. In the volume-restricted setting the complete volume was absorbed by all swabs, volume release could only be detected for flocked swabs (2.7 mg; p<0.001). Highest amount of CFU release was detected for the MWE Dryswab in the unrestricted setting for both S. aureus and S. epidermidis with 1544 CFU and 553 CFU, respectively, lowest release for the Sarstedt neutral swab with 32 CFU and 17 CFU, respectively (p<0.001). In the volume-restricted setting MWE Σ-Swab released the highest bacterial amount with 135 CFU S. aureus and 55 CFU S. epidermidis, respectively, the lowest amount was released by Mast Mastaswab with 2 CFU S. aureus and 1 CFU S. epidermidis, respectively (p<0.001). Within the range of the utilized bacterial concentrations, uptake/release ratios were identical for the particular swab types and independent of the bacterial species.
The influence of the swab type on subsequent diagnostic results is often underestimated. Uptake and release of the investigated bacteria vary significantly between different swab types and sampling conditions. For best diagnostic outcome swabs should be chosen according to the examined situation and the swab performance profile.
拭子广泛用于从各种临床环境中采集样本进行微生物分析。它们在材质、尺寸和头部结构方面存在差异。本研究调查了拭子对液体和细菌的吸收及释放能力。
分析了五种拭子对金黄色葡萄球菌和表皮葡萄球菌悬液的吸收及释放能力。研究了两种方法，提供体积受限和不受限的细菌悬液量以模拟各种临床情况。分别以毫克为单位测量体积以及通过计数菌落形成单位（CFU）来测量细菌的吸收和释放量。
在不受限的情况下，体积吸收量在239.6毫克至88.7毫克之间（p<0.001），体积释放量在65.2毫克至2.2毫克之间（p<0.001），差异非常显著。在体积受限的情况下，所有拭子都吸收了全部体积，仅在植绒拭子中检测到体积释放（2.7毫克；p<0.001）。在不受限的情况下，对于金黄色葡萄球菌和表皮葡萄球菌，MWE Dryswab释放的CFU数量最多，分别为1544 CFU和553 CFU，Sarstedt中性拭子释放的数量最少，分别为32 CFU和l7 CFU（p<0.001）。在体积受限的情况下，MWE Σ - 拭子释放的细菌数量最多，金黄色葡萄球菌和表皮葡萄球菌分别为135 CFU和55 CFU，Mast Mastaswab释放的数量最少，金黄色葡萄球菌和表皮葡萄球菌分别为2 CFU和1 CFU（p<0.001）。在所使用的细菌浓度范围内，特定拭子类型的吸收/释放比率相同，且与细菌种类无关。
拭子类型对后续诊断结果的影响常常被低估。不同拭子类型和采样条件下，所研究细菌的吸收和释放存在显著差异。为获得最佳诊断结果，应根据检查情况和拭子性能特征选择拭子。
