Paluch-Oleś Jolanta, Magryś Agnieszka, Kozioł-Montewka Maria, Niedzielski Artur, Niedźwiadek Justyna, Niedzielska Grażyna, Kotowski Michał
Department of Medical Microbiology, Medical University of Lublin, Lublin, Poland.
Int J Pediatr Otorhinolaryngol. 2011 Jan;75(1):126-30. doi: 10.1016/j.ijporl.2010.10.025. Epub 2010 Nov 18.
Medical biofilms are involved in a number of chronic infections including otitis media with effusion and chronic rhinosinusitis, which are common pediatric infectious diseases. The purpose of the study was to analyze the phenotypic and genotypic indicators of biofilm formation of coagulase negative staphylococci isolates in children with otitis media with effusion, and in children with chronic rhinosinusitis as a comparison group by using three different detection methods.
Forty nine children aged from 2 to 6 years old, diagnosed with otitis media with effusion were enrolled to the study. The comparative group consisted of twenty three strains of coagulase-negative staphylococci from the strains collection isolated from nose swabs from children 3 to 7 years old suffering from rhinosinusitis for longer than 12 weeks. Cultured strains were tested for biofilm formation ability with three tests: Congo red agar, tissue culture plate methods and detection of ica operon.
Out of 97 ear effusion specimens, obtained from 49 children suffering from OME, 38 were found positive in conventional culture resulting in isolation of 50 different bacterial species. Nested-PCR method confirmed bacterial presence in 95 (97.9%) cases. Among 50 different bacterial species isolated, 30 (30.9%) CNS and 20 (20.6%) other than CNS species. Detection of slime producing phenotype of CNS was performed with CRA plate test. Among OME isolates, 11 (36.7%) were CRA plate test positive. In case of isolates from CRS, 8 (34.8%) strains revealed black coloration on CRA. Using TCP method, strong adherence to microtiter plate was observed in two Staphylococcus epidermidis strains from OME and two S. epidermidis from CRS. By using the ica operon test, the genotypic ability to form biofilm was identified in 7 (23.3%) S. epidermidis strains cultured from ears effusion and in 3 (13%) strains from nose swabs.
CNS strains revealed genotypic and phenotypic features responsible for the ability to form the biofilm in vivo. The presence of ica genes and phenotypic ability to form a biofilm by CNS strains emphasizes the pathogenic character of these strains in some cases of otitis media with effusion.
医学生物膜与多种慢性感染有关，包括分泌性中耳炎和慢性鼻-鼻窦炎，这些都是常见的儿科感染性疾病。本研究的目的是通过三种不同的检测方法，分析分泌性中耳炎患儿以及作为对照组的慢性鼻-鼻窦炎患儿中凝固酶阴性葡萄球菌分离株生物膜形成的表型和基因型指标。
49名年龄在2至6岁、诊断为分泌性中耳炎的儿童被纳入研究。对照组由从3至7岁患有鼻窦炎超过12周的儿童鼻拭子中分离的23株凝固酶阴性葡萄球菌组成。对培养的菌株进行三种试验以检测生物膜形成能力：刚果红琼脂试验、组织培养板法和ica操纵子检测。
从49例分泌性中耳炎患儿获得的97份耳积液标本中，38份在常规培养中呈阳性，分离出50种不同的细菌种类。巢式聚合酶链反应方法在95例（97.9%）病例中证实有细菌存在。在分离出的50种不同细菌种类中，30种（30.9%）为凝固酶阴性葡萄球菌，20种（20.6%）为非凝固酶阴性葡萄球菌。用CRA平板试验检测凝固酶阴性葡萄球菌产生黏液的表型。在分泌性中耳炎分离株中，11株（36.7%）CRA平板试验呈阳性。在慢性鼻-鼻窦炎分离株中，8株（34.8%）菌株在CRA上呈现黑色。采用TCP法，在2株来自分泌性中耳炎的表皮葡萄球菌菌株和2株来自慢性鼻-鼻窦炎的表皮葡萄球菌菌株中观察到对微量滴定板的强黏附。通过ica操纵子试验，在从耳积液培养的7株（23.3%）表皮葡萄球菌菌株和从鼻拭子培养的3株（13%）菌株中鉴定出形成生物膜的基因型能力。
凝固酶阴性葡萄球菌菌株显示出在体内形成生物膜能力的基因型和表型特征。凝固酶阴性葡萄球菌菌株ica基因的存在及其形成生物膜的表型能力强调了这些菌株在某些分泌性中耳炎病例中的致病特性。
