چالش های تشخیص آزمایشگاهی کووید 19: یک مطالعه مبتنی بر rt-pcr

ﻣﻘﺪﻣﻪ: در دﺳﺎﻣﺒﺮ 2019 ﯾﮏ ﮐﺮوﻧﺎوﯾﺮوس ﺟﺪﯾﺪ ﺑﻪ ﻧﺎم 2-sars-cov در ووﻫﺎن ﭼﯿﻦ ﮐﺸﻒ ﺷﺪ ﮐﻪ روشﻫﺎی ﻣﻮﻟﮑﻮﻟﯽ ﺣﺴﺎﺳﯽ ﺑﺮای ﺗﺸﺨﯿﺺ آن اﺑﺪاع ﺷﺪه اﺳﺖ. ﻫﺪف از ﻣﻄﺎﻟﻌﻪ ﺣﺎﺿﺮ، ﺗﺸﺨﯿﺺ ﺻﺤﯿﺢ ﻣﺒﺘﻼﯾﺎن و ﻫﻤﭽﻨﯿﻦ ﺑﺮرﺳﯽ ﭼﺎﻟﺶﻫﺎی ﻣﻮﺟﻮد در ﺗﺸﺨﯿﺺ اﯾﻦ وﯾﺮوس ﺑﺎ روش real-time pcr (rt-pcr)- ﺑﻪ ﻃﻮر ﻋﻤﻠﯽ اﺳﺖ. روش ﮐﺎر: 271 ﻧﻔﺮ ﺷﺎﻣﻞ 105 زن و 166 ﻣﺮد ﺑﻪ روش ﺳﺮﺷﻤﺎری از 15 ﻓﺮوردﯾﻦ ﻣﺎه ﺗﺎ ﺗﯿﺮ ﻣﺎه ﺳﺎل 1399 در اﯾﻦ ﻣﻄﺎﻟﻌﻪ ﻧﺎم ﻧﻮﯾﺴﯽ ﺷﺪﻧﺪ. ﻧﻤﻮﻧﻪﻫﺎی ﺳﻮآب ﻧﺎزوﻓﺎرﯾﻨﮋﯾﺎل و اوروﻓﺎرﯾﻨﮋﯾﺎل از اﻓﺮاد ﻣﺸﮑﻮک ﺟﻤﻊ آوری و اﺳﺘﺨﺮاج rna ﺑﺮای ﺗﺸﺨﯿﺺ وﯾﺮوس ﺑﺎ روش rt-pcr اﻧﺠﺎم ﮔﺮﻓﺖ. ﯾﺎﻓﺘﻪﻫﺎ: 52 ﻧﻔﺮ از زﻧﺎن و 82 ﻧﻔﺮ از ﻣﺮدان از ﻟﺤﺎظ ﮐﻮوﯾﺪ 19 ﻣﺜﺒﺖ ﺑﻮدﻧﺪ. ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﮐﻪ در اﯾﻦ ﺑﺎزه زﻣﺎﻧﯽ در ﮐﯿﺖﻫﺎی درﯾﺎﻓﺘﯽ، ﻣﺤﺘﻮای ﮐﯿﺖﻫﺎی rt-pcr ﺑﺎ ﮐﻨﺘﺮل ﻣﺜﺒﺖ آﻟﻮدﮔﯽ داﺷﺘﻨﺪ. در ﻫﺸﺖ درﺻﺪ ﻣﻮارد ﻧﻤﻮﻧﻪﻫﺎی ﻗﻄﻌﯽ ﮐﻨﺘﺮل ﻣﻨﻔﯽ ﭘﺲ از ﻣﺮﺣﻠﻪ اﺳﺘﺨﺮاج و در ﻓﺮاﯾﻨﺪ rt-pcr ﺑﺎ ﻣﺴﺘﺮ ﻣﯿﮑﺲ واﮐﻨﺶ و ﭘﯿﮏﻫﺎﯾﯽ در دﺳﺘﮕﺎه ﻧﺸﺎن دادهاﻧﺪ. از ﺳﻮﯾﯽ، ﻧﺘﺎﯾﺞ ﻣﻄﺎﻟﻌﻪ ﺣﺎﺿﺮ ﻧﺸﺎن داد ﮐﻪ در ﻫﻔﺖ درﺻﺪ از ﮐﯿﺖﻫﺎ، ﻣﺤﺘﻮای ﻣﺴﺘﺮ ﻣﯿﮑﺲ ﺑﺪون اﻓﺰودن ﻧﻤﻮﻧﻪ ﺧﻮد ﺑﻪ ﺧﻮد در دﺳﺘﮕﺎه ﭘﯿﮏﻫﺎﯾﯽ ﻣﺸﺎﺑﻪ ﮐﻨﺘﺮل ﻣﺜﺒﺖ اﯾﺠﺎد ﻣﯽ ﮐﻨﻨﺪ. ﻧﺘﯿﺠﻪ ﮔﯿﺮی: ﮐﻨﺘﺮل ﻣﻨﻔﯽﻫﺎی ﻣﺘﻌﺪدی ﺑﺮای ﺗﺸﺨﯿﺺ وﯾﺮوس ﮐﻮوﯾﺪ 19 در ﻣﺮﺣﻠﻪ اﺳﺘﺨﺮاج و rt-pcr ﻻزم اﺳﺖ ﺗﺎ از ﺑﺮوز ﭘﺎﺳﺦ ﻣﺜﺒﺖ ﮐﺎذب جلوگیری شود.

laboratory diagnosis challenges of covid-19: a real-time rt-pcr assay-based survey

introduction: a novel coronavirus has recently been discovered in wuhan, china in december 2019 named sars-cov-2. sensitive molecular assays are now available for detection of sars-cov-2. the aims of this study were to detect positive subjects of sars-cov-2 and to survey some challenges that are encountered practically in detection of the virus by real-time rt-pcr (rrt-pcr) technique.materials and methods: 271 subjects including 105 women and 166 men were registered by census method from 15 april to 15 jun of 2020. nasopharyngeal and oropharyngeal swab samples of suspicious cases were collected for rna extraction to identify sars-cov-2 by rrt-pcr amplification.results: 69% of the positive sars-cov-2 patients over the age 50 were men. however, technically the results showed that in the time period of 15 april to 15 may of 2020 the contents of received rrt - pcr kits were infected with positive control.  8 % of certain negative control samples showed a signal resembling to that of the positive samples in the rrt - pcr process. in addition, the results showed that in some of the rrt - pcr kits the master mix would produce signals like positive control without adding the sample to it automatically in 7 % of the tests.conclusion: having different types of negative control for diagnosis of sars-cov-2 is necessary to reduce the chance of having false positive results.