11. Alvarado score
Migration of pain 心窩部、臍周囲→右下腹部 1
MANTRELS score
Anorexia 食欲不振 1
Nausea 嘔気、嘔吐 1
Tenderness in RLQ 右下腹部痛 1
Rebound tenderness 反跳痛 2
Elevated temperature 発熱＞37.3℃ 1
Leukocytosis WBC>10,000/µl 2
Shift of WBC count 白血球の左方移動 1
7点以上; Sn 24-95%, Sp 46-99%, LR 3.1
5-6点; Sn 4-43%
4点以下; Sn 0-28%, Sp 6-87%, LR 0.1
12. Temperature ≥7.3°C 28 (14.7%) symptoms, and 93% of patients had tenderness in the right
White blood cell count (/μL) 11 999.7 ± 4420.9 lower quadrant of the abdomen. The signs and symptoms
研修医の印象とAlvarado scoreは
White blood cell count ≥ 10 000/μL 126 (66.0%) used to calculate the Alvarado score are shown in Table 1.
Segmented neutrophil (%) 76.8 ± 11.4
Of a total of 191 patients, 120 (62.8%) patients underwent
Segmented neutrophil ≥75% 121 (63.4)
surgical exploration and 71 (37.2%) were discharged home.
Data are expressed mean ± SD or number (percentage) as appropriate. Of the 120 patients who underwent exploration, one patient
どちらが有用か？
was compared using the χ 2 or Fisher exact test as
was diagnosed with an ovarian torsion before operation and
the surgery was performed by a gynecologist. The remaining
American Journal of went to the operating room with the impression
119 patients Emergency Medicine (2010) 28, 766–770
appropriate. We performed receiver operating characteristic of acute appendicitis. Of these patients, 111 (93.2%) were
curve analysis to compare the diagnostic characteristics of confirmed to have appendicitis by pathologic findings, and
ER研修医, 外科研修医が右下腹部痛でER受診した191名を評価
EMR, SR, the Alvarado score, and the CT scan. The area
under the curve (AUC) was calculated and a univariate Z test
one was found to have a mucinous tumor. Telephone follow-
up was completed on all patients who did not undergo
was used to compare the AUC as described by Hanley and operation, and there was no additional case of acute
McNeil [10]. appendicitis within the 3-month follow-up period.
虫垂炎に対する診断能をROC curveで評価.
Statistical analyses were conducted using SPSS software
version 13.0 (SPSS Inc, Chicago, Ill). Medcalc (MedCalc
Software, Belgium) was used to compare the AUC. A P value
of less than .05 was considered statistically significant.
AUCは,
3. Results
CT; " " " 0.978[0.953-1.002]
During the study period, 278 consecutive patients with
pain to the right lower quadrant of the abdomen were
Alvarado; " 0.735[0.661-0.809]
enrolled. Of these patients, 87 were not evaluated by an SR
before CT imaging and were excluded. Therefore, 191
ER研修医; " 0.698[0.622-0.773]
patients were included into the final analysis. Their mean age
was 37.3 ± 16.7 years and 87 patients (45.6%) were male.
Nausea and vomiting were the most common presenting
外科研修医;" 0.657[0.579-0.735]
Table 2 Comparison of the probability groups between EMR
and SRs
Group Surgery (N = 191)
15. cantly higher PPV (95% vs 71%). The US-
aided identification of a normal appen-
dix was a significantly more common
finding for the exclusion of appendicitis
虫垂炎所見; 直径が9.3mm
than was the normality of both WBC and
CRP levels (72% vs 47%) and had a sig-
nificantly higher NPV (98% vs 84%).
DISCUSSION
The inability to visualize the normal ap-
pendix is classically considered a major
weakness of using US in the assessment
Figure 1. (a) Transverse and (b) longitudinal US images obtained in a 27-year-old man with of patients suspected of having appendi-
正常の虫垂所見
appendicitis (arrows). The appendix has an anteroposterior diameter of 9.2 mm. citis, because it represents a serious limi-
tation to confidently excluding the diag-
nosis of appendicitis (5). In their state-of-
using US and 21 patients in whom it was cluded eight patients with ileocolitis (Fig the-art article, Birnbaum and Wilson (9)
not identified. Of these latter 21 patients, 5), four patients with mesenteric adeni- claimed that in their experience and in
two had a final diagnosis of appendicitis, tis, one patient with mesenteric isch- that of others (11,15), a normal appendix
thus giving the lack of visualization of emia, and one patient with pyelonephri- is visualized in only 0%– 4% of cases in
the appendix at US an NPV of 90%; each tis. Cecal wall thickening (Fig 5) was the adult population, regardless of the US
of these two patients was found to have detected at US in only 25% of patients technique used, and they stated that the
an appendiceal perforation at surgery. with appendicitis and in more than 10% results of Rioux (12), who visualized a
The 104 patients in whom the appendix of patients without appendicitis. Perito- normal appendix in 82% of patients
was visualized constituted a group in neal fluid was noted in 51% of patients without acute appendicitis, were “amaz-
Figure 2.appendiceal US findings could be a normal appendix (arrows) in three different patients.
which (a– c) Longitudinal US images show with appendicitis but also in almost 30% ing.”
基部は正常径だが,
tested. Table 2 shows (a) the frequency of patients without appendicitis. Right In contrast with this classic viewpoint,
with which each appendiceal finding was lower abdominal quadrant adenopathy we visualized a normal appendix in 72%
normal appendix visualization rate (12).
interpreted as positive or negative, (b) the was present in 32% of patients with ap- of the patients without appendicitis,
As a result, nonvisualization of the ap- TABLE 2 末端で肥大した虫垂
number of true-positive, true-negative, pendicitis and in 38% of patients without for the Diagnosisclose to the 64% appendix
Appendiceal US and Doppler US Signs which is a rate of Appendicitis
pendix can only befalse-negative results, appendicitis. Combining the nonappen- visualization rate obtained by Retten-
false-positive, and valid as an accurate
Radiology
finding to exclude appendicitis for sonog-
and (c) the sensitivity, specificity, accu- diceal findings with appendiceal findings Lack of
Finding and Diameter Ն Intraluminal
bacher et al (19) in a population of
raphers whoand PPV of each appendiceal did not increase the NPV or PPV of indi- healthy subjects. The notion thatWall
racy, NPV, can usually identify a normal Value 6 mm Compressibility Fluid Flow in
the
appendix.The two most accurate appen- vidual appendiceal findings, such as an normal appendix is seldom visualized at
finding. Finding at US
US evaluation ofappendicitis were a di- appendix 6 mm or larger55 diameter or 55 is based on reports published more
diceal findings for the appendix ideally Positive in US 33 30
includes of 6 mm or of theand a lack of noncompressibility of the50
ameter evaluation larger appendiceal Negative
appendix. 49 71 74
than 10 years ago (10,14) or on data ob-
wall and appendiceal content. with de- Finding at final
compressibility. In the patient We ap- diagnosis tained by sonographers who are not ra-
cided to measure the outer appendiceal
pendicitis and an outer appendiceal di- diologists with experience in US28 assess-
diameter less than 6 mm, surgical wall Laboratory Findings 54
True-positive 53 29
ameter rather than appendiceal and True-negative 48 47 45 47
ment of the gastrointestinal tract (20).
thickness forexamination First, as shown
pathologic two reasons. revealed distal
by Rioux (12), inflammation of the ap-
The number
False-negative
1
1
糞石と
False-positive of true-positive, true-neg- 2 4
Technologic advances combined with in-
2 26
2
26
appendicitis, but, although the distal ap- ative, false-positive, and false-negative re- depth radiologic experience have dra-
Value*
pendiceal wall may be indistinguishable
pendix was dilated in comparison with Figure 3. the sensitivity,(95, 100) shows ap- 100)
Sensitivity
fromproximal one,intraluminal pus, thus showsNPV, and PPV of the two laboratory (94, 100)
hypoechoic both the proximal and racy, ap-
粘膜内Fluid貯留
sults and Longitudinal US image accu- (94,
98 specificity, 96 matically improved 63) use of US in the
53 (43, the 52 (43, 61)
the Radiology 2004;230:472-8
Figure 3. Longitudinal US image pendicitis in a 43-year-old woman. This 96 a
Specificity 98 (95, 100) was visualization 92 (87, 97)
of a normal appendix. The
96 (94, 100)
making measurement of the appendiceal false-negative diagnosis at US. The appendiceal 100) improvement94)
PPV 98 WBC levels) are (94,
(95, 100) 96 same 88 (82, has been (88, 98)
93 reported
pendicitis in a 43-year-old woman. findings (ie, CRP and (95, 100)
distal appendix measured less than 6 mm This was a
NPV in Table 4. A WBC level above (94, 100)
98 96 with use of computed tomography 73)
63 (64, 72) 64 (55, (CT);
wallUS (Fig 3). Second, the mucosal sur- diameter measured less than 6 mm, but after a
at inaccurate. In the nonappendicitis shown
false-negative diagnosis at US. The appendiceal
