22-이준영

대한응급의학회지제 22 권제 6 호 Volume 22, Number 6, December, 2011 원 저 요관결석의위치와크기에따른임상양상고찰 연세대학교의과대학응급의학교실, 관동대학교의과대학응급의학교실 1 이준영 좌민홍 1 김현종 이누가 정성필 이한식 김민정 Relationship of Clinical Manifestation of Renal Colic to Ureteral Stone Size and Location June Young Lee, M.D., Minhong Choa, M.D. 1, M.D., Hyun Jong Kim, M.D., Nuga Rhee, M.D., Sung Phil Chung, M.D., Hahn Shick Lee, M.D., Min Joung Kim, M.D. (94.9%). The factor affecting the response to analgesic treatment was stone size. Patients needing analgesic administration three times or more, had smaller stones. Conclusion: Most of the ureteral stones observed were located in the proximal ureter and at the ureterovesical junction. Hydronephrosis occurred more often in patients who had longer periods of pain and larger stones. Patients with smaller stones needed more frequent administration of pain killers. Purpose: This study was designed to correlate the size and position of ureteral stones to their clinical manifestation. Methods: This study was a retrospective review of medical records of 201 patients who visited the emergency department complaining of renal colic and diagnosed with ureteral stone(s) by use of computed tomography from July to December 2011. The size and position of a stone and the corresponding ipsilateral hydronephrosis, as well as the number and type of administered analgesics, were evaluated. Results: Ureteral stones were located at the ureteropelvic junction in 2.0% of cases, at the proximal ureter between the ureteropelvic junction and the iliac vessels in 41.8% of cases, at the ureter crossing external iliac vessels in 1.0% of cases, at the distal ureter between the iliac vessels and the ureterovesical junction in 12.9% of cases, and at the ureterovesical junction in 42.3% of cases. Where the ureter crossed external iliac vessels, the mean size of stones was significantly larger in the upper ureter, as 5.3±2.3 mm, than in the lower ureter, as 4.2±1.8 mm. Pain duration and stone size were significant factors associated with hydronephrosis by logistic regression analysis. Ketorolac was selected as the first-line analgesics in 169 patients 책임저자 : 김민정서울특별시강남구언주로 211 강남세브란스병원응급의학과 Tel: 02) 2019-3030, Fax: 02) 2019-4820 E-mail: boringzzz@yuhs.ac 접수일 : 2011년 10월 4일, 1차교정일 : 2011년 10월 18일게재승인일 : 2011년 11월 3일 728 Key Words: Ureteral calculi, Hydronephrosis, Pain Department of Emergency Medicine, Yonsei University College of Medicine, Seoul, Korea, Department of Emergency Medicine, Kwandong University College of Medicine, Gyeonggi-do, Korea 1 서 요통은응급실로내원하는흔한주증상중하나이다. 전체인구가운데 5~15% 가일생동안한차례이상의요관결석으로인한통증을경험한다고알려져있다 1,2). 요관결석의전형적인증상인갑작스럽게발생한동측사타구니로방사되는통증과혈뇨로내원하는환자들의경우, 문진과신체검사및소변검사만으로도요관결석을진단할수있다. 하지만복부대동맥동맥류나신동맥경색과같이요관결석과비슷한증상을보이는위급한질환들이있어고령이거나저혈압등임상적으로의심이되는경우에는반드시영상검사를통해정확히감별진단하는것이필요하다. 정맥신우조영술, 비조영전산화단층촬영, 초음파등다양한영상검사가요관결석의진단에사용되어왔다 3-5). 1923년정맥신우조영술이도입된이후정맥신우조영술이요관결석진단의최적의검사로알려졌으나 1990년대이후비조영전산화단층촬영이요관결석의진단에적용된이래로 100% 의민감도와 97% 의특이도를보여경정맥신우조영술을능가하는요관결석의진단도구로평가되고있다 3,6). 전산화단층촬영은요관결석의존재를확인하는것외에, 다른질환을배제할수있고요관결석에의한합병증과 론

이준영외 : 요관결석의위치와크기에따른임상양상고찰 / 729 요관결석의위치및크기를정확하게확인할수있어향후치료계획을수립하는지표로사용될수있다 7,8). 또한검사시간이 10분내외로짧고전처치를요하지않으며환자에게불편감을유발하지않기때문에응급실환경에적합하여오늘날요관결석의진단에가장선호되고있다 9). 요관결석진단에전산화단층촬영의이용이증가하면서이를통해결석의위치나크기, 수신증이나요관확장등의이차징후들, 자연배출예측인자에대한연구들이이루어졌다 8,10-13). 하지만아직요관결석의특성에따른환자들의임상양상의차이에대한연구는미비한실정이다. 이에본저자는요관결석환자들의전산화단층촬영결과를토대로결석의위치와크기를분석하고그에따른임상양상의특성을고찰하고자한다. 대상과방법 1. 연구대상 2010년 7월1일부터 2010년 12월 31일까지 6개월동안일개지역응급의료센터에요통을주소로내원하여복부전산화단층촬영을통해요관결석을진단받은환자들을후향적으로조사하였다. 신장결석 5명과결석이방광내부에위치한 11명의환자, 그리고복부전산화단층촬영에서요관확장등의요관결석으로인한이차징후는관찰되나결석이확인되지않아자연배출된상태로의심되는 9명의환자를제외하였다. 통증의동측에두개이상의결석을가진 6명의환자는분석대상에서제외하였고, 통증의반대쪽신장에결석이관찰되나통증의동측에는한개의결석만이확인된환자 2명은포함시켰다. 요관결석의과거력이있는환자가 57명이있었는데, 이전시술여부나요관협착등의합병증에따라요관결석의위치나수신증에영향을줄가능성이있어분석대상에서제외하게되었다. 최종적으로 201명의환자가연구대상이되었다. 세명의응급의학전문의가전산화단층촬영영상에서요관결석의크기와위치, 수신증동반여부를조사하였다. 요관결석의크기는가로영상 (Axial image) 에서의가장긴직경으로정의하였고, 세명이측정한값의평균값으로결정하였다. 결석의위치는신우요관이행부 (Ureteropelvic junction), 신우요관이행부와바깥엉덩혈관교차부사이의근위부요관 (proximal ureter), 바깥엉덩혈관교차부 (Ureter crossing external iliac vessel), 바깥엉덩혈관교차부와방광요관이행부사이의원위부요관 (distal ureter), 방광요관이행부 (Ureterovesical junction) 로분류하였다. 결석의위치와수신증동반여부에대한세명의전문의의의견에불일치가있는경우에는전원이모인자리에서합의를통하여결정하였다. 모든환자는 Simens사의 64-channel multi-detector row computed tomography scanner (Somatom Sensation 64; Siemens Medical Solutions, Erlangen, Germany) 를이용하여 5 mm 간격으로구성한 Picture Archiving and Communication System (PACS) 영상을통하여요관결석이진단되었다 (100 kvp, 220 mas, pitch 1.0). 3. 통계통계는나이, 통증의강도, 결석의크기등의연속변수들은 Student s t-test로분석하여평균 ± 표준편차로보여주었는데, 통증의기간은평균값과중앙값에큰차이를보여 Mann-Whitney U test 로분석하여중앙값 ( 사분위수 ) 로기술하였다. 빈도변수는 Pearson s chi-square test로이용하였고, 로지스틱회귀분석으로수신증에영향을주는요인과통증조절과관련된요인을분석하였다. p값이 0.05 미만일때통계학적으로유의한것으로판정하였고, 분석은 SPSS software, Window 12.0 version (SPSS Inc., Chicago, IL, USA) 을사용하였다. 2. 자료수집 결 과 환자의의무기록에서통증의발생시간, 내원당시의통증척도 (Visual Analogue Scale), 늑골척추각압통 (Costovertebral angle tenderness) 유무, 요관결석의과거력, 진료결과입퇴원여부등을조사하였다. 그리고병원정보시스템 (Hospital information system) 을통해투여한진통제의종류및횟수를조사하였고혈청크레아티닌수치와소변검사에서의혈뇨유무를확인하였다. 콩팥요관방광단순촬영 (Kidney ureter bladder, KUB) 에서의요관결석진단과전산화단층촬영에서의신우신염동반여부는영상의학과전문의의판독을기준으로하였다. 1. 요관결석의위치와임상적인특징총 201명의환자를대상으로분석하였다. 결석의위치는요관방광이행부결석이 85명 (42.3%) 으로가장많았고, 근위부요관이 84명 (41.8%) 으로두번째로많았으며, 원위부요관에 26명 (12.9%), 신우요관이행부에 4명 (2.0%), 요관과바깥엉덩혈관의교차부위에 2명 (1.0%) 순이었다 (Fig. 1). 바깥엉덩혈관교차부를기준으로상부요관과하부요관으로나누어환자들의일반적인특성과요관결석과관련된임상적인특성을비교하였다 (Table 1). 증

730 / 대한응급의학회지 : 제 22 권제 6 호 2011 상발현으로부터응급실내원까지의시간은양군모두중앙값이 2.0시간이었고통증의강도에는유의한차이를보이지않았다. 결석의크기는 5.3±2.3 mm와 4.2±1.8 mm으로상부요관결석의크기가더컸다 (p<0.001). 상부요관결석의 64.4%, 하부요관결석의 51.4% 에서수신증이동반되었다 (p=0.062). 결석과동측의신장에신우신염이발생한환자는 2명 (1.0%) 이었는데모두상부요관결석에서동반되었다. 신우신염환자를포함한 14명 (7.0%) 의환자가응급실진료결과입원하였다. 2. 수신증과관련된요인들전체환자의 57.2% 에서수신증을동반하였다. 수신증발생에영향을주는요인들을알아보기위한로지스틱회귀분석결과통증이오래될수록, 결석의크기가클수록수신증이잘발생하였다 (Table 2). 각결석위치에서의수신증여부에따른결석의크기는 Fig. 2 와같다. 3. 통증조절과관련된요인들 201명의환자가운데 178명 (88.6%) 에서진통제가투여되었다 (Table 3). 가장처음투여된진통제로는 ketorolac tromethamine이 169건 (94.9%) 으로가장많이사용되었다. 두번이상진통제가사용된환자는 52명으로전체환자의 25.9% 에해당하였다. 진통조절과관련된요인으로는결석의크기를확인할수있었다 (p= 0.003)(Table 4). 두차례이상진통제가투여된환자들의결석크기는평균 3.9±1.8 mm였고, 한번투약된환자들의결석크기는 4.9±2.2 mm였다 (p=0.002). 고 찰 Fig. 1. Location of ureteral stones. UPJ: Ureteropelvic junction UEIV: Ureter crossing external iliac vessel UVJ: Ureterovesical junction 본연구에서요관결석이진단된전산화단층촬영에서결석위치를분석한결과, 근위부요관과요관방광이행부가총요관결석의 84.1% 를차지하였고, 신우요관이행부와바깥엉덩혈관교차부의결석은각각 4명 (2.0%) 과 2명 (1.0%) 에지나지않았다. 신우요관이행부와요관이바깥엉덩혈관 Table 1. Comparison of clinical characteristics according to the position of stone Position of stone Variables Upper ureter (n=90) Lower ureter (n=111) p-value Age, mean±sd 42.6±13.3 44.8±13.4 <0.230* Male gender, n (%) 62 (68.9) 079 (71.2) <0.725* Pain duration (hour), median (IQR) 2.0 (1.0, 5.0) 2.0 (1.0, 4.0) <0.498* Pain scale (VAS), mean±sd 5.7±1.9 5.4±1.9 <0.246* CVAT, n (%) 59 (65.6) 079 (71.2) <0.393* Left-side, n (%) 56 (62.2) 058 (52.3) <0.156* Stone size, mean±sd 5.3±2.3 4.2±1.8 <0.001* <5 mm, n (%) 47 (52.2) 084 (75.7) <0.001* Hydronephrosis, n (%) 58 (64.4) 057 (51.4) <0.062* Microscopic hematuria, n (%) 87 (96.7) 104 (93.7) <0.517* Serum creatinine, mean±sd 1.0±0.2 1.0±0.2 <0.798* Visible in KUB, n (%) 50 (55.6) 049 (44.1) <0.121* Combined with APN, n (%) 02 (02.2) 0 <0.199* Admission, n (%) 09 (10.0) 005 (04.5) <0.166* SD: Standard deviation, IQR: Interquartile range, VAS: Visual analogue scale, CVAT: Costovertebral angle tenderness, KUB: Kidney ureter bladder, APN: Acute pyelonephritis

이준영외 : 요관결석의위치와크기에따른임상양상고찰 / 731 과교차되는부위, 요관방광이행부는요관이해부학적으로가장좁아지는부위로, 교과서적으로는이세부위에요관결석이가장많이위치한다고알려져있다 14,15). 하지만오래전이루어진연구들은경정맥신우조영술이나 X선검사에의존하였기때문에전산화단층촬영만큼결석의위치를정확하게확인할수없었으리라생각된다. Song 등 11) 과 Eisner 등 10) 도요관결석환자들의전산화단층촬영분석연구를통해요관결석은대부분상부요관과요관방광이행부에위치하며신우요관이행부와바깥엉덩혈관교차부는더이상요로결석호발부위가아니라고제시한바있다. 상부요관에비해하부요관에위치한결석의크기는더작았고, 원위부요관으로갈수록작은결석들도수신증을동반하였다. 초음파로요관결석을진단하고자할때결석자체를확인하는것은민감도가낮은반면수신증은민감도 100% 로초음파로정확하게확인가능하여수신증여부가결석의진단률을높이는데에도움을주게된다 16,17). 따라서결석의위치및크기에따라수신증이동반될가능성에대해이해하는것은초음파를이용한결석진단에도움이될수있다. 요관결석의해부학적인특징과함께수신증을임상적으로해석할때고려해야할요인은통증의기간 Table 2. Logistic regression analysis of the factors affecting hydronephrosis Variables Significance Odds ratio 95% confidence interval lower upper Univariate analysis Age 0.999* 1.000 0.979 1.021 Sex 0.147* 0.630 0.337 1.177 Pain duration 0.012* 1.066 1.014 1.119 Pain scale 0.786* 0.980 0.846 1.134 CVAT 0.225* 0.685 0.371 1.263 Intractable pain 0.684* 1.142 0.601 2.170 Stone location 0.063* 0.582 0.329 1.030 Stone size 0.012* 1.213 1.044 1.408 Side 0.134* 1.547 0.875 2.736 Visible in KUB 0.963* 0.986 0.548 1.775 Multivariate analysis Pain duration 0.018* 1.060 1.010 1.113 Stone size 0.030* 1.185 1.016 1.381 CVAT; Costovertebral angle tenderness, KUB; Kidney ureter bladder Fig. 2. Stone size according to the stone location and hydronephrosis. Because of low number of case, ureteropelvic junction (UPJ) and ureter crossing external iliac vessel (UEIV) were omitted from the figure UVJ: Ureterovesical junction

732 / 대한응급의학회지 : 제 22 권제 6 호 2011 이다. 본연구에서는응급실내원하기전통증의기간과수신증은여부는유의한상관관계를보였다. Michael 등 18) 은수신증을포함한요관폐쇄의이차징후들과증상발현시점과의관계를연구하였는데, 통증발생으로부터시간이경과할수록이차징후의동반확률이높아지며수신증의경우 8시간이상경과하였을때 89% 에서동반한다는결과를보여주었다. 여러논문들이요관결석에서의수신증빈도를다양하게보고하고있는것은이러한맥락에서이해할수있을것이다 19,20). 전산화단층촬영이초음파보다요관결석진단의정확성면에서는우위에있지만높은비용이나방사선조사문제로인해모든요관결석의심환자에대한첫번째영상검사로선택하기에는부적합한면이있다 21). 기존연구결과에따르면 5 mm 이하의결석은 68~78% 에서자연배출되고, 요관방광이행부결석인경우는약 92% 까지도자연배출된다고보고된바있다 8,22). 보존적치료후에결석이자연배출되는경우가많고, 응급실에서즉각적인비뇨기과적시술을요하는경우는드물기때문에모든환자에서정확하게요관결석의위치와크기를진단해야하는가에대해의문을제기할수있다 23). 요관결석의자연배출을예측하기위해통증조절정도와결석의크기의상관관계를확인하고자한연구가있었 다. Prina 등 24) 의이연구에서는결석이 6 mm 이상으로큰경우요관폐쇄가심해지면서더많은진통제를필요로할것이라는가설로시작하였지만두요인간의상관관계를확인하지는못하였다. 그들은통증은주관적인느낌이며개개인의교육정도나문화에따라영향을받기때문에유의한결과를얻을수없었다고기술하였다. 하지만우리의연구에서는일반적인예상과는다르게작은결석일수록통증조절이잘되지않는다는반대의결과를얻게되었다. 전통적으로요관결석으로인해통증이유발되는기전은결석으로인한요관폐쇄가집합계 (collecting system) 내강의압력을증가시키면서물리적인견인을유발하는것과동시에고유판 (lamina propria) 의신경말단을자극하는것으로이해되어왔다. 집합계의팽창에반응하여요관의평활근은결석을움직이기위해수축하게되고, 결석이요관에걸려움직일수없게되면근경련이발생한다 25-27). 요관폐쇄에따른신장의혈류와요관의압력은시간의흐름에따라달라지는데, 폐쇄시점을기준으로 0~1.5시간동안에는동시에증가하기시작하다가, 1.5~5시간동안에는혈류는감소하지만요관압력의증가는지속되며, 5~18시간동안에는양쪽모두감소하게된다 28,29). 요관산통의일차치료제로권장되고있는비스테로이드항염증제 (nonsteroidal anti-inflammatory drugs, NSAIDs) 는프로스 Table 3. Used analgesics Analgesics Number of patients (%) 1 st 2 nd 3 rd Ketorolac 169 (94.9) 18 (34.6) 2 (25.0) Tramadol 006 (03.4) 06 (11.5) 0 Morphine 002 (01.1) 13 (25.0) 4 (50.0) Meperidine 001 (00.6) 15 (28.8) 2 (25.0) Total 178 52 8 Table 4. Logistic regression analysis of the factors affecting analgesics administration more than twice Variables Significance Odds ratio 95% confidence interval Univariate analysis Age 0.201* 0.984 0.960 1.009 Sex 0.223* 0.659 0.338 1.288 Pain duration 0.710* 0.995 0.970 1.021 Pain scale 0.061* 1.177 0.993 1.395 CVAT 0.138* 1.735 0.837 3.594 Stone location 0.167* 1.581 0.826 3.027 Stone size 0.003* 0.750 0.620 0.907 Side 0.869* 0.948 0.501 1.794 Hydronephrosis 0.684* 1.142 0.601 2.170 Visible in KUB 0.698* 0.875 0.445 1.719 CVAT: Costovertebral angle tenderness, KUB: Kidney ureter bladder lower upper

이준영외 : 요관결석의위치와크기에따른임상양상고찰 / 733 타글란딘 (prostaglandin) 의합성을억제함으로써들세동맥 (afferent arteriole) 의혈류증가를줄여요관의압력을줄여줌과동시에요관평활근의수축을억제시켜통증을감소시킨다 26,30). 이러한통증발생기전에결석의크기와요관폐쇄정도가어떤차이를일으키게되고진통제에의한효과를달라지게하는지에대한연구는아직이루어지지않았다. 작은결석이움직이면서지속적으로요관내막을자극함으로써통증조절을어렵게할수있지않을까추측해보지만본연구만으로는증명하기어려운부분으로요관결석의크기에따라통증기전에미치는영향을연구해볼필요가있다. 결석의크기나자연배출가능성을예측할수있는임상적요인들을찾을수있다면비용효과면에서검사및치료방침의효율적인선택에도움이되리라생각된다. 본연구의제한점은첫째, 미세한요관결석인경우 5 mm 간격의영상에서는안보일수있어서연구대상에서제외되었을가능성이있다. 또한전산화단층촬영만으로결석의크기를측정하였기때문에크기에오차가있을수있다. 둘째, 요관결석의치료에일정한프로토콜이없었다는점이다. 본연구에서는진통제가두차례이상투여된환자를통증조절이잘되지않는군으로구분하였는데, 진통제의선택은해당환자를진료한의사가자율적으로판단하였고이차약제투여역시프로토콜이없이의사개개인의판단에따라결정되었기때문에진통제투여횟수는객관적인지표로서한계를지닌다. 결 응급실에서전산화단층촬영을통해요관결석이진단된환자들을분석한결과결석은대부분근위부요관과요관방광이행부에위치하였다. 요관결석의크기가클수록통증이기간이길수록수신증이많이동반되었다. 두차례이상진통제가투여된환자들은그렇지않은환자들에비해결석의크기가작은특성을보였고결석의위치나수신증여부는유의한차이를보이지않았다. 론 참고문헌 01. Pearle MS, Calhoun EA, Curhan GC. Urologic diseases in America project: urolithiasis. J Urol 2005;173:848-57. 02. Teichman JM. Clinical practice. Acute renal colic from ureteral calculus. N Engl J Med 2004;350:684-93. 03. Smith RC, Rosenfield AT, Choe KA, Essenmacher KR, Verga M, Glickman MG, et al. Acute flank pain: comparison of non-contrast-enhanced CT and intravenous urography. Radiology 1995;194:789-94. 04. Yilmaz S, Sindel T, Arslan G, Ozkaynak C, Karaali K, Kabaalioglu A, et al. Renal colic: comparison of spiral CT, US and IVU in the detection of ureteral calculi. Eur Radiol 1998;8:212-7. 05. Erwin BC, Carroll BA, Sommer FG. Renal colic: the role of ultrasound in initial evaluation. Radiology 1984;152: 147-50. 06. Mendelson RM, Arnold-Reed DE, Kuan M, Wedderburn AW, Anderson JE, Sweetman G, et al. Renal colic: a prospective evaluation of non-enhanced spiral CT versus intravenous pyelography. Australas Radiol 2003;47:22-8. 07. Cullen IM, Cafferty F, Oon SF, Manecksha R, Shields D, Grainger R, et al. Evaluation of suspected renal colic with noncontrast CT in the emergency department: a single institution study. J Endourol 2008;22:2441-5. 08. Coll DM, Varanelli MJ, Smith RC. Relationship of spontaneous passage of ureteral calculi to stone size and location as revealed by unenhanced helical CT. AJR Am J Roentgenol 2002;178:101-3. 09. Phillips E, Kieley S, Johnson EB, Monga M. Emergency room management of ureteral calculi: current practices. J Endourol 2009;23:1021-4. 10. Eisner BH, Reese A, Sheth S, Stoller ML. Ureteral stone location at emergency room presentation with colic. J Urol 2009;182:165-8. 11. Song HJ, Cho ST, Kim KK. Investigation of the location of the ureteral stone and diameter of the ureter in patients with renal colic. Korean J Urol 2010;51:198-201. 12. Eisner BH, Pedro R, Namasivayam S, Kambadakone A, Sahani DV, Dretler SP, et al. Differences in stone size and ureteral dilation between obstructing proximal and distal ureteral calculi. Urology 2008;72:517-20. 13. Kishore TA, Pedro RN, Hinck B, Monga M. Estimation of size of distal ureteral stones: noncontrast CT scan versus actual size. Urology 2008;72:761-4. 14. Resnick MI, Novick AC. Urology Secrets. 3rd ed. New York: Elsevier; 2002. p.300. 15. Brunicardi FC, Andersen DK, Billiar TR, Dunn DL, Hunter JG, Pollock RE. Schwartz s Principles of Surgery. 8th ed. Columbus, Ohio: McGraw Hill; 2004. p.2000. 16. Ripolles T, Agramunt M, Errando J, Martinez MJ, Coronel B, Morales M. Suspected ureteral colic: plain film and sonography vs unenhanced helical CT. A prospective study in 66 patients. Eur Radiol 2004;14:129-36. 17. Sheafor DH, Hertzberg BS, Freed KS, Carroll BA, Keogan MT, Paulson EK, et al. Nonenhanced helical CT and US in the emergency evaluation of patients with renal colic: prospective comparison. Radiology 2000;217:792-7. 18. Varanelli MJ, Coll DM, Levine JA, Rosenfield AT, Smith RC. Relationship between duration of pain and secondary

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