원저 Lab Med Online Vol. 5, No. 1: 27-32, January 2015 임상미생물학 호흡기세포융합바이러스검출에있어 Multiplex RT-PCR 법과의비교를통한 Binax NOW RSV 의임상적유용성평가 Comparison of the Clinical Performance of Binax NOW RSV Versus Multiplex RT-PCR for Detection of Respiratory Syncytial Virus 손종애 1 * 김시현 1,3 * 신정환 1,3 전가원 2 신종범 2 이자영 1 김혜란 1 전경란 1 이정녀 1 송새암 1 Jong Ae Son, M.D. 1 *, Si Hyun Kim, Ph.D. 1,3 *, Jeong Hwan Shin, M.D. 1,3, Ga Won Jeon, M.D. 2, Jong Beom Sin, M.D. 2, Ja Young Lee, M.D. 1, Hye Ran Kim, M.D. 1, Kyung Ran Jun, M.D. 1, Jeong Nyeo Lee, M.D. 1, Sae Am Song, M.D. 1 인제대학교의과대학진단검사의학교실 1 소아청소년과학교실 2, 인제대학교의과대학백인제기념임상의학연구소 3 Departments of Laboratory Medicine 1, and Pediatrics 2, Inje University College of Medicine, Busan; Paik Institute for Clinical Research 3, Inje University College of Medicine, Busan, Korea Background: Respiratory syncytial virus (RSV) is one of the most important causes of lower respiratory tract infection. The rapid antigen test is a simple, cheap, and quick method for RSV detection, however, it has an acknowledged low sensitivity. The aim of this study is to evaluate the diagnostic performance of the rapid antigen test by comparing it with a multiplex reverse transcription-pcr (RT-PCR). Methods: A total of 557 nasopharyngeal aspirates or swabs that were submitted for both a rapid antigen test, Binax NOW RSV (Binax; Alere Scarborough, Inc., USA) and multiplex RT-PCR, Seeplex RV7 (Seegene Inc., Korea) were included in this study. We performed both tests according to the manufacturer s recommendations and analyzed the diagnostic performances of a rapid antigen tests based on the results of multiplex RT-PCR. Results: Among the 557 specimens, the positive rates determined from the rapid antigen test and multiplex RT-PCR were 12.2% (N=68) and 25.1% (N=140), respectively. The relative sensitivity and specificity of the rapid antigen test were 46.4% and 99.3% based on the multiplex RT- PCR, respectively. Positive and negative predictive values were 95.6% and 84.7%, respectively. The diagnostic sensitivity was lower (28.6%) in children >36 months compared with children 36 months of age. Test sensitivity declined when RSV infection was accompanied by infection with other respiratory viruses. Conclusions: Binax NOW RSV exhibited good diagnostic performance, easy handling, and rapidity. However, it does have the possibility of falsenegative results, and additional tests are needed when there is clinical suspicion of RSV infection. Key Words: Respiratory syncytial virus, Rapid antigen, Multiplex reverse transcription-pcr Corresponding author: Sae Am Song Department of Laboratory Medicine, Hae Un Dae Paik Hospital, Inje University College of Medicine, 875 Haeundae-ro, Haeundae-gu, Busan 612-896, Korea Tel: +82-51-797-3188, Fax: +82-51-797-3194, E-mail: cute-sammy@hanmail.net *These two authors contributed equally to this study. Received: February 19, 2014 Revision received: May 20, 2014 Accepted: May 29, 2014 This article is available from http://www.labmedonline.org 2015, Laboratory Medicine Online This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. 서론 호흡기세포융합바이러스 (respiratory syncytial virus, RSV) 는 Paramyxoviridae 과의 Pneumovirus에속하는단일가닥 RNA 바이러스로서소아에서바이러스하기도감염증을일으키는가장흔한원인중하나이다 [1]. 특히이바이러스는 2세이전의영아및유아에서급성세기관지염, 폐렴과같은중증질환을일으킬수있는데미국에서는 RSV로인한입원이매년 10만명정도발생하는것으로보고하였다 [2]. 국내의한보고에서는바이러스로인한급성호흡기감염증으로입원한소아환자들을대상으로호흡기바이러스를분리했을때 RSV가 41.8% 로가장많았다고보고하였다 [3]. 또한 RSV는영유아뿐아니라노인이나면역저하자에서도급성 eissn 2093-6338 www.labmedonline.org 27
호흡기감염을일으킬수있는주요원인이되며중이염, 뇌염등의중증질환도일으킨다. 그러나임상증상만으로원인바이러스를감별하기가어렵기때문에치료기간및합병증을줄이고불필요한항생제남용을피하기위해서는신속하고정확한진단이필요하다 [4]. RSV 검출을위한진단방법으로는세포배양법, 면역형광염색법, 신속항원검출법, 핵산증폭법등이있으며신속항원검출법과핵산증폭법이현재가장널리사용되고있다. 핵산증폭법은다중역전사중합효소연쇄반응 (multiplex reverse transcription polymerase chain reaction, multiplex RT-PCR) 에근거한방법을이용한것으로민감도와특이도가매우우수하고한번의반응으로여러종의호흡기바이러스를동시에감별할수있어최근진단검사의학검사실에서배양검사를대체하여널리이용되고있다 [5, 6]. 신속항원검출법은비용이저렴하고 15-30분이내에결과를보고할수있으며특별한장비나시설이필요하지않아일선검사실에서가장널리사용되는방법이다 [7]. Binax NOW RSV (Binax; Alere Scarborough, Inc., Scarborough, ME, USA) 는전세계적으로가장많이사용되고있는신속항원검출법으로국내의많은검사실에서도이방법을사용하고있다. 그러나최근환자를진료하는일선현장에서이를사용했을때실제검사법의민감도가기존의보고와달리낮다는의견들이있어이와관련된국내자료를찾아보았으나이와연관된연구결과를찾을수없었다. 이에저자들은 RSV에의한호흡기감염의진단을위한신속항원검출법인 Binax NOW RSV의임상적유용성을평가하고자하였다. 대상및방법 Multiplex RT-PCR은 Seeplex RV7 (Seegene Inc., Seoul, Korea) 을사용하였다. Viral Gene-spin Viral DNA/RNA Extraction kit (intron Biotechnology Inc., Seongnam, Korea) 와 MagNA Pure LC RNA isolation kit (Roche GmbH, Mannheim, Germany) 를이용하여검체로부터 RNA를추출하고추출된 RNA를 random hexamer 1µL와 DEPC-treated water 3µL가첨가되어있는혼합물에 8µL씩첨가하여핵산증폭기에 80 에서 3분간반응시킨후얼음에 2분간방치하여 RNA 혼합물을만들었다. 이것을다시 cdna synthesis kit (RevertAid First Strand cdna Synthesis Kit, Fermentas, USA) 에넣어 37 에서 90분, 90 에서 5분간반응시켜 cdna 를합성하였다. 합성된 cdna를 PCR premixture와함께혼합하여 94 에서 15분간변성시키고, 94 30초, 60 90초, 72 90초로 40회반복한후 72 에서 10분간확장하고 4 에정치하여 PCR반응을실시한후 2% agarose gel에서전기영동하여증폭된 PCR 산물을확인하였다. 3. 평가방법 Binax NOW RSV의진단적유용성을평가하고자 multiplex RT- PCR에포함된 RSV의결과를기준으로하여민감도, 특이도, 양성예측도 (Positive predictive value, PPV), 음성예측도 (Negative predictive value, NPV) 를구하였으며이값들을환자의연령, RSV 감염의유행시기및다른호흡기바이러스의중복감염여부에따라분류하여분석하였다. 연령은 12개월미만, 12-36개월사이, 36개월이상의세환자군으로, 유행시기는 RSV가유행하는 4월에서 10 월사이와비유행시기인 5월에서 9월사이로분류하였고또한 multiplex RT-PCR 에포함되어있는다른호흡기바이러스의중복감염여부에따라서구분하였다. 1. 대상발열, 기침등의호흡기증상을주소로진단검사의학과에의뢰된검체중 RSV 신속항원검사와 multiplex RT-PCR 이동시에의뢰된 557개의호흡기검체를대상으로하였다. 2. 검사방법 RSV 신속항원검사로는 Binax NOW RSV를사용하였으며이는 RSV 항원이존재할경우, 항원은검사띠표면에존재하는항 RSV 항체에부착되고, 이혼합체형성의결과로검사띠아래부분의대조선과검체의반응선이변색되는면역크로마토그래피법을원리로 RSV 융합단백질항원을검출하도록고안되었다. 검체는면봉이나흡입기를이용하여비인두검체를채취하였으며검체를떨어뜨리고 15분후청색에서분홍혹은보라색으로변색되면양성으로해석하였다. 4. 통계분석집단간의차이는카이제곱검정 (chi square test) 및피셔정확검정 (Fisher s exact test) 을이용하여비교하였다. 모든통계분석은 MedCalc (version 12.4.0, MedCalc Software, Mariakerke, Belgium) 를이용하여양측검정을하였으며, P값 0.05 미만을통계학적인유의성을가지는기준으로하였다. 결과총 557개의검체중 Binax NOW RSV와 multiplex RT-PCR 의양성률은각각 12.2% (N = 68) 및 25.1% (N =140) 이었다. Multiplex RT-PCR 결과를기준으로비교했을때신속항원검사의민감도는 46.4% (65/140), 특이도는 99.3% (414/417) 이며양성예측도와음성예측도는각각 95.6% (65/68), 84.7% (414/489) 였다 (Table 1). 28 www.labmedonline.org
민감도와특이도, 양성예측도와음성예측도를환자의연령에따 라세군으로구분하여비교했는데연령에따른민감도는통계적 으로유의한차이를보이지않았고 (P = 0.349) 가장높은민감도를 보인 12-36 개월사이환자군의민감도가 51.3% 로기존의보고에 비하여낮게나타났다 [2]. 그러나특이도는세군모두에서유의한 차이없이 98.4-100.0% 로높았다 (P = 0.424). 바이러스유행시기별로구분하여 RSV 유행시기인 10-4 월사이 의민감도와특이도, 비유행시기인 5-9 월사이의민감도와특이도 를비교하였다. 바이러스의유행시기에따른민감도는유의한차 이를보이지않았으며 (P = 0.406), 다소높은민감도를보인비유행 시기에도민감도가 55% 를넘지않았다. 특이도의경우바이러스 유행시기에상관없이 98.7-100.0% 로높았다 (P = 0.257). 다른호흡기바이러스와중복감염이있는경우또는 RSV 이외 의다른바이러스만검출된경우이에의한간섭현상으로위음성 또는위양성의가능성을고려해볼수있다. 이에다른호흡기바이 Table 1. Diagnostic performance of the rapid antigen test compared to multiplex RT-PCR RT-PCR Positive Binax NOW RSV Negative Total Positive 65 75 140 Negative 3 414 417 Total 68 489 557 러스의존재유무는 multiplex RT-PCR 결과를참조하였으며이번연구대상에서검출된호흡기바이러스는 rhinovirus가가장높은빈도로나타났으며그다음으로 parainfluenza, influenza A, human metapneumovirus, adenovirus 의순으로검출되었다. 다른호흡기바이러스의존재유무에따른신속항원검사의민감도역시통계적으로유의한차이를보이지않았으며 (P = 0.686), 다른호흡기바이러스가존재하지않을경우민감도가 47% 로상대적으로높았으나기존의보고에비해서는낮게나타났다 [2]. 특이도는다른호흡기바이러스의존재유무에따른차이를보이지않았다 (P = 0.566; Table 2). 고찰 RSV는급성호흡기감염증의주요원인으로, 특히영유아및소아에서높은유병률과이환율을보인다 [8, 9]. 결막이나코점막을통해전파되므로전염성이강하고영아와노인그리고면역저하환자와같은환자군에서는호흡부전까지도일으킬수있다. 하지만 RSV의다양한항원성때문에아직까지이러한감염증을효과적으로예방할수있는백신이없는상태여서적절한진단과치료를위해서는신속한진단이필수적이다 [10]. RSV감염의진단법으로는전통적인바이러스세포배양법과면역형광항체검사법등이있다. 바이러스배양검사는 RSV 진단의표준 Table 2. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the rapid antigen test according to age, seasonality, and presence of other viruses Age Sensitivity (95% CI) Specificity (95% CI) PPV (95% CI) NPV (95% CI) <12 months (N=182) 42.1% (29.1-55.9%) 98.4% (94.3-99.8%) 92.3% (74.9-99.1%) 78.8% (71.6-85.0%) (24/57) (123/125) (24/26) (123/156) 12-36 months (N=301) 51.3% (39.6-63.0%) 99.6% (97.6-100.0%) 97.5% (86.8-99.9%) 85.8% (81.0-89.8%) (39/76) (224/225) (39/40) (224/261) >36 months (N=74) 28.6% (3.7-71.0%) 100.0% (94.6-100.0%) 100.0% (15.8-100.0%) 93.1% (84.5-97.7%) Seasonality (2/7) (67/67) (2/2) (65/72) RSV peak season (Oct.-Apr.) (N=351) 45.0% (35.9-54.4%) 98.7% (96.3-99.7%) 94.7% (85.4-98.9%) 77.6% (72.4-82.2%) (54/120) (228/231) (54/57) (228/231) Offseason (May-Sep.) (N=206) 55.0% (31.5-76.9%) 100.0% (98.0-100.0%) 100.0% (71.5-100.0%) 95.4% (91.4-97.9%) Other viruses present* (11/20) (186/186) (11/11) (186/195) Yes (N=119) 33.3% (4.3-77.7%) 100.0% (96.8-100.0%) 100.0% (15.8-100.0%) 96.6% (91.5-99.1%) (2/6) (113/113) (2/2) (113/117) No (N=438) 47.0% (38.3-55.8%) 99.0% (97.1-99.8%) 95.5% (87.3-99.1%) 80.9% (76.6-84.8%) (63/134) (301/304) (63/66) (301/372) Total (N=557) 46.4% (38.0-55.1%) 99.3% (97.9-99.9%) 95.6% (87.6-99.1%) 84.7% (81.2-87.7%) (65/140) (414/417) (65/68) (414/489) *adenovirus (N=8), adenovirus+rhinovirus (N=2), adenovirus+parainfluenza (N=1), influenza A (N=22), Influenza B+rhinovirus (N=1), metapneumovirus (N=10), parainfluenza (N=26), rhinovius (N=46), rhinovirus+parainfluenza (N=3). www.labmedonline.org 29
검사법이지만, 배양기간이길고숙련된검사자가필요한단점이있다 [7]. 특히최근분자진단법이소개된이후진단검사의학검사실에서의바이러스배양검사의이용도는현저히줄어들었다. 면역형광항체검사법은배양법에비해검사시간이더짧지만, 고도의검사기술이필요하고검사자간재현성과양성검출률에서차이를보일수있어현재임상검사실에서의이용은매우제한적이다 [11]. 핵산증폭검사는동시에여러종의호흡기바이러스를검출할수있을뿐아니라민감도와특이도가높고검사시간이짧다는장점이있어최근호흡기바이러스감염의진단을위해가장널리이용되고있으나분자진단검사의수행을위해숙련된검사자가필요하고검사를위한별도의장비및시설이요구되는단점이있다 [12, 13]. 신속항원검사는별도의장비나시설없이도간단하고신속하게호흡기바이러스를검사할수있고비용도상대적으로저렴해일선의료현장에서가장많이사용되고있는방법으로분자진단검사를이용하고있는종합병원에서도응급검사로유용하게활용되고있다. 하지만진료현장에서환자의진단에이용시낮은민감도가문제가된다 [14]. 이러한이유로새로운신속항원진단키트를이용할때각검사실에서는사용하고있는해당키트의진단적유용성에대하여인지하고있어야한다. RSV의진단을위한신속항원검사로는대부분 Binax NOW RSV, BD Directigen RSV 및 BD Directigen EZ RSV (Becton Dickinson and Company, Sparks, Maryland) 를사용하고있으며기존의배양법또는핵산증폭방법과비교하였을때민감도는 59.0-94.6%, 특이도는 88.5-100.0% 로보고되어있다 [2, 15-19] (Table 3). 두가지이상의신속항원검사를대상으로비교한보고도매우유용하다. Ohm-Smith 등 [15] 의보고에서 BD Directigen EZ와 Binax NOW RSV의민감도는각각 59.0% 와 89.0%, 특이도는 98.0% 와 100.0% 였고, Zheng 등 [16] 은 BD Directigen EZ와 Binax NOW RSV의민감도는각각 86.5% 와 94.6%, 특이도는 92.3% 와 88.5% 로보고하였다. 이들두연구만보더라도동일한키트내에서상당한민감도의차이를보이고특이도의경우서로상반된결과를보이 고있지만, 민감도의경우두연구모두에서 Binax NOW RSV가더나은성적을보였다. 하지만 Zheng 등 [16] 의보고는포함된검체수가 89개로매우제한적일뿐만아니라, 민감도와특이도가각각 94.6% 와 88.5% 로민감도가기존의다른보고에비해유독높은반면특이도는기존의보고중가장낮은수치를보이며특히민감도가특이도보다높은결과를보여주고있어결과의해석에유의할필요가있다. 이번연구와동일한신속항원검사법인 Binax NOW RSV를평가한보고중 Zheng 등 [16] 의결과를제외한자료를정리하면, 민감도는 72.2-89.0%, 특이도는 93.2-100.0% 로신속항원검사임에도불구하고높은진단적유용성을보여주고있다. 특히 Cruz 등 [18] 은 3 년에걸쳐 14,000건이상의검체를대상으로배양과비교하여 Binox NOW RSV의유용성에대해평가하였는데전체민감도는 81.0% (78.0-83.6%), 특이도는 93.2% (92.8-93.6%) 로보고하여신뢰성있는데이터를제공하고있을뿐만아니라, 우수한진단적유용성을보여주고있다. 이러한기존의결과를참조하여본검사실에서도진단적유용성을평가하였으며 Binax NOW RSV의결과를 multiplex RT-PCR 의결과와비교하였을때민감도가 46.6% 로기존에보고된결과보다낮았으며특이도는 99.3% 로기존의연구결과와유사하였다. 연령의구분에의한차이는성인보다소아에서신속항원검사의민감도가더우수한것으로알려진보고가있으며 [20, 21], 이번연구의결과에서도 36개월이하의소아에서의민감도는 47.4% 인반면, 36개월이상의소아나성인의민감도는 28.6% 로차이를보여, 성인에서신속항원검사를사용할경우결과해석에주의가필요할것으로생각된다. 다른호흡기바이러스가존재할경우신속항원검사의민감도는단일감염일경우보다더낮게나타나이들바이러스의존재가위음성의결과에영향을미칠수있음도의심되지만특정바이러스와의관련성은보이지않았고, 이번연구에서추가적인확인은하지못했다. 또한비유행시기에비하여유행시기의검사민감도가낮게나타나는데이는경미한증상에도유행시기 Table 3. Comparison of the antigen immunoassay with other diagnostic methods with respect to sensitivity, specificity, PPV and NPV Test method and Standard method Sensitivity (95% CI) Specificity (95% CI) PPV (95% CI) NPV (95% CI) Reference Binax NOW RSV vs. Multiplex RT-PCR (N=557) 46.4% (38.0-55.1%) 99.3% (97.9-99.9%) 95.6% (87.6-99.1%) 84.7% (81.2-87.7%) This study Binax NOW RSV vs. RT-qPCR (N=311) 72.2% (60.9-81.7%) 97.0% (94.5-99.1%) 90.0% (80.4-96.4%) 91.0% (86.9-94.4%) [2] Binax NOW RSV vs. RSV culture (N=270) 81.7% (73.2-88.1%) 98.7% (94.9-99.8%) 97.9% (92.0-99.6%) 87.9% (81.9 92.2%) [19] Binax NOW RSV vs. RSV culture (N=118) 89.0% (73.3-96.8%) 100.0% (95.7-100.0%) 100.0% (88.8-100.0%) 95.0% (88.6-98.7%) [15] Binax NOW RSV vs. RSV culture (N=14,756) 81.0% (78.0-83.6%) 93.2% (92.8-93.6%) 40.4% (38.0-42.9%) 98.9% (98.7-99.0%) [18] Binax NOW RSV vs. RSV shell vial culture (N=89) 94.6% (81.8-99.3%) 88.5% (76.6-95.7%) 85.4% (70.8-94.4%) 95.8% (85.8-99.5%) [16] Binax NOW RSV vs. DFA+RSV shell vial culture (N=162) 74.0% (58.9-85.1%) 100.0% (96.8-100.0%) 100.0% (90.3-100.0%) 90.0% (83.0-94.4%) [17] BD Directigen EZ vs. RSV culture (N=88) 59.0% (36.4-79.3%) 98.0% (91.8-100.0%) 93.0% (66.1-99.8%) 88.0% (78.2-94.3%) [15] BD Directigen EZ vs. RSV shell vial culture (N=89) 86.5% (71.2-95.5%) 92.3% (81.5-97.9%) 88.9% (73.9-96.9%) 90.6% (79.3-96.9%) [16] BD Directigen RSV vs. RSV shell vial culture (N=89) 86.5% (71.2-95.5%) 88.5% (76.6-95.7%) 84.2% (68.8-94.0%) 90.2% (78.6-96.7%) [16] 30 www.labmedonline.org
임을고려한처방의증가로인해신속항원검사에서는낮은바이러스량등으로음성을보이나검출한계가높은 multiplex RT-PCR 에서는양성결과를나타내어상대적으로신속항원검사의민감도가낮게나타나는것으로추정해볼수있다. 신속항원검사의민감도는연구자에따라매우다양하게보고되고있으며사용한키트의종류, 검체의종류, 환자의연령, 검사자의숙련도, 환자의임상적증상이나발현시기등에따라결과에차이를보일수있다는것을주지할필요가있다. 특히기존의국외보고에만의존할경우상대적으로민감도를높게평가할수있음도함께고려해야할것이다. 따라서국내의신속항원검사의민감도가기존의알려진것보다낮다는점을고려하여신속항원검사를선별검사로단독사용할경우, 결과가음성이더라도 RSV 감염을완전히배제할수없고임상적으로 RSV 감염이의심될때에는필요에따라핵산증폭검사와같은추가검사를시행하여바이러스유무를확인해야함을인지하여야한다. 아울러이번연구에서분석된검사결과가환자의임상적증상이나발현시기등과같은검사결과에영향을미칠수있는변수가고려되지않았다는점과 Binax NOW RSV의결과를바이러스배양과비교하지않고다중역전사중합효소연쇄반응결과와비교, 분석하였다는점이한계점으로생각된다. 요약 배경 : 호흡기세포융합바이러스는하기도감염의주요원인균이다. 신속항원검사는검사방법이간단하고검사소요시간이짧으며비용이저렴한장점이있으나상대적으로민감도가낮은단점이있다. 이번연구에서는다중역전사중합효소연쇄반응과비교하여신속항원검사의진단적유용성을평가하고자하였다. 방법 : RSV 신속항원검사 (Binax; Alere Scarborough, Inc., USA) 와다중역전사중합효소연쇄반응 (Seegene Inc., Korea) 이동시에의뢰된총 557개의비인두흡인액혹은비인두면봉채취검체를대상으로두검사모두제조사의권고방법대로검사하였다. 신속항원검사의진단적유용성은다중역전사중합효소연쇄반응결과를기준으로하여민감도, 특이도, 양성예측도, 음성예측도를평가하였다. 결과 : 총 557개의검체중신속항원검사와다중역전사중합효소연쇄반응의양성률은각각 12.2% (N = 68) 와 25.1% (N =140) 였다. 다중역전사중합효소연쇄반응을기준으로하였을때신속항원검사의민감도는 46.4%, 특이도는 99.3% 였으며양성예측도는 95.6%, 음성예측도는 84.7% 였다. 나이군에따라서는 36개월이상의환자군에서민감도가 28.6% 로가장낮았고다른호흡기바이러스가동반된경우민감도가감소하는양상을보였다. 결론 : Binax NOW RSV 키트는사용이간편하고검사소요시간이 15분으로짧아 RSV의조기진단에유용한검사법이다. 그러나민감도가낮아위음성률이높기때문에임상에서사용할때에는이점에유념하여결과를해석해야할것이다. REFERENCES 1. Simoes EA. Respiratory syncytial virus infection. Lancet 1999;354:847-52. 2. Miernyk K, Bulkow L, DeByle C, Chikoyak L, Hummel KB, Hennessy T, et al. Performance of a rapid antigen test (Binax NOW RSV) for diagnosis of respiratory syncytial virus compared with real-time polymerase chain reaction in a pediatric population. J Clin Virol 2011;50: 240-3. 3. Kim MR, Lee HR, Lee GM. Epidemiology of acute viral respiratory tract infections in Korean children. J Infect 2000;41:152-8. 4. Kim SH, Huh JH, Bae SY, Kim JS, Yoon SY, Lim CS, et al. Epidemiology of respiratory viral infection in 2004-2006. Korean J Lab Med 2006;26: 351-7. 5. Henrickson KJ. Advances in the laboratory diagnosis of viral respiratory disease. Pediatr Infect Dis J 2004;23(1 Suppl):S6-10. 6. Stockton J, Ellis JS, Saville M, Clewley JP, Zambon MC. Multiplex PCR for typing and subtyping influenza and respiratory syncytial viruses. J Clin Microbiol 1998;36:2990-5. 7. Petric M, Comanor L, Petti CA. Role of the laboratory in diagnosis of influenza during seasonal epidemics and potential pandemics. J Infect Dis 2006;194(Suppl 2):S98-110. 8. Jennings LC, Anderson TP, Werno AM, Beynon KA, Murdoch DR. Viral etiology of acute respiratory tract infections in children presenting to hospital: role of polymerase chain reaction and demonstration of multiple infections. Pediatr Infect Dis J 2004;23:1003-7. 9. Mohapatra SS and Boyaplle S. Epidemiologic, experimental, and clinical links between respiratory syncytial virus infection and asthma. Clin Microbiol Rev 2008;21:495 504. 10. Sidwell RW and Barnard DL. Respiratory syncytial virus infections: recent prospects for control. Antiviral Res 2006;71:379-90. 11. Halstead DC, Todd S, Fritch G. Evaluation of five methods for respiratory syncytial virus detection. J Clin Microbiol 1990;28:1021-5. 12. Henrickson KJ and Hall CB. Diagnostic assays for respiratory syncytial virus disease. Pediatr Infect Dis J 2007;26(11 Suppl):S36-40. 13. Freymuth F, Vabret A, Cuvillon-Nimal D, Simon S, Dina J, Legrand L, et al. Comparison of multiplex PCR assays and conventional techniques www.labmedonline.org 31
for the diagnostic of respiratory virus infections in children admitted to hospital with an acute respiratory illness. J Med Virol 2006;78:1498-504. 14. Barenfanger J, Drake C, Leon N, Mueller T, Troutt T. Clinical and financial benefits of rapid detection of respiratory viruses: an outcomes study. J Clin Microbiol 2000;38:2824-8. 15. Ohm-Smith MJ, Nassos PS, Haller BL. Evaluation of the Binax NOW, BD Directigen, and BD Directigen EZ assays for detection of respiratory syncytial virus. J Clin Microbiol 2004;42:2996-9. 16. Zheng X, Quianzon S, Mu Y, Katz BZ. Comparison of two new rapid antigen detection assays for respiratory syncytial virus with another assay and shell vial culture. J Clin Virol 2004;31:130-3. 17. Borek AP, Clemens SH, Gaskins VK, Aird DZ, Valsamakis A. Respiratory syncytial virus detection by Remel Xpect, Binax Now RSV, direct immunofluorescent staining, and tissue culture. J Clin Microbiol 2006; 44:1105-7. 18. Cruz AT, Cazacu AC, Greer JM, Demmler GJ. Performance of a rapid assay (Binax NOW) for detection of respiratory syncytial virus at a children s hospital over a 3-year period. J Clin Microbiol 2007;45:1993-5. 19. Liao RS, Tomalty LL, Majury A, Zoutman DE. Comparison of viral isolation and multiplex real-time reverse transcription-pcr for confirmation of respiratory syncytial virus and influenza virus detection by antigen immunoassays. J Clin Microbiol 2009;47:527-32. 20. Aldous WK, Gerber K, Taggart EW, Thomas J, Tidwell D, Daly JA. A comparison of Binax NOW to viral culture and direct fluorescent assay testing for respiratory syncytial virus. Diagn Microbiol Infect Dis 2004; 49:265-8. 21. Jonathan N. Diagnostic utility of BINAX NOW RSV an evaluation of the diagnostic performance of BINAX NOW RSV in comparison with cell culture and direct immunofluorescence. Ann Clin Microbiol Antimicrob 2006;5:13. 32 www.labmedonline.org