Some Are More Equal - A Comparative Study on Swab Uptake and Release of Bacterial Suspensions

ObjectivesSwabs 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.MethodsFive 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.ResultsVolume uptake and release in the unrestricted setting varied highly significant between 239.6 mg and 88.7 mg (pS. 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 (pS. 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 (pConclusionsThe 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.研究目的：拭子（swabs）是各类临床场景中微生物学分析样本采集的常用工具，其材质、尺寸及头部结构因产品不同存在显著差异。本研究旨在探究不同拭子对液体与细菌的摄取及释放能力。 研究方法：本研究共纳入5款拭子，针对其对金黄色葡萄球菌（Staphylococcus aureus）与表皮葡萄球菌（Staphylococcus epidermidis）悬液的摄取与释放能力开展检测分析。实验设置两种方案，分别提供体积受限与无体积限制的细菌悬液，以复现不同临床场景。液体的摄取与释放量以毫克为单位测定，细菌的摄取与释放量则通过菌落形成单位（CFU）计数法完成量化。 研究结果：无体积限制组的液体摄取与释放量差异极显著，区间为239.6 mg至88.7 mg（p值原文缺失）。针对金黄色葡萄球菌与表皮葡萄球菌，其细菌释放量分别为1544 CFU与553 CFU，其中Sarstedt中性拭子的细菌释放量最低，分别为32 CFU与17 CFU（p值原文缺失）；而当目标细菌释放量对应55 CFU的金黄色葡萄球菌与表皮葡萄球菌时，Mast Mastaswab的细菌释放量最低，仅为2 CFU的金黄色葡萄球菌与1 CFU的表皮葡萄球菌（p值原文缺失）。 研究结论：拭子类型对后续诊断结果的影响常被忽视与低估。不同拭子类型与采样条件下，目标细菌的摄取与释放能力均存在显著差异。为获得最佳诊断效果，应根据实际检测场景与拭子性能参数选择适配的拭子产品。