acute abdomen

1. Discussion
Acute abdomen is a surgical emergency Patterson, Kashyap,&
Dominique, 2017. It can represent a wide spectrum of conditions, ranging from
a benign and self-limiting disease to a surgical emergency. Nevertheless, only
one quarter of patients who have previously been classified with an acute
abdomen actually receive surgical treatment, so the clinical dilemma is if the
patients need surgical treatment or not and, furthermore, in which cases the
surgical option needs to be urgently adopted Samal, et al 2021.
Ultrasound (US) is the preferred imaging modality in children, pregnant
women, and generally young patients, owing to the absence of ionizing
radiation. Advances in computed tomography (CT) with multi-planar
reformations and 3D reconstruction have led to some clinicians considering
multi-detector CT (MDCT) as the modality of choice when evaluating patients
with right iliac fossa pain. CT is considered to be the first line imaging
investigation Caraiani, et al., 2020.
The aim of this study was to clarify role of multi detector CT versus
ultrasonography in the evaluation of non traumatic acute abdomen.
This prospective observational study was performed in Department of
Radio-diagnosis KASR EL-AINY and Hurghada general hospitals. It was
conducted on 55 patients with non traumatic acute abdomen presented to the ED

2. that was clinically diagnosed acute abdomen. Patients with acute abdominal
pain were evaluated with both ultrasonography and computed tomography.
Ultrasonography was done first followed by computed tomography in
ultrasonography (US) positive cases, in symptomatic patients with negative US
scans and in patients with suboptimal scan.
The current study results showed that the mean age among the
participants was 37.4 years ranging from 14 to 82 years. The most common age
group was 15-30 years (41.8 %) followed by 31 -40 years, 41-60 years then<60
years (25.5 %, 25.5 % and 7.2%), respectively.
A study was conducted to compare the efficacy of US and CT in
diagnosis of acute abdomen. It was found that the mean age of the patients was
49.2 years Kumar & Badhan, 2020.
Panigrahi, et al conducted a study to assess the clinical features and
diagnosis of acute abdomen. It was found that the most common age group
was50-59 years that is higher than that found in the current study (18.3%),
followed by 40-49 years (17.2%) Panigrahi, et al, 2021. This difference may
be caused by the difference in the common causative diagnoses.
In the present study, Most of the study population were males (67%),
while 33% were females, M: F ratio of 2:1.Similarly, in a study conducted by

3. Gajjar, et al. it was found that 63% of the study population were males, while
37% were females (Gajjar, et al., 2017).
Also, Azeem, found that among 204 patients who presented in ER
department with chief complaint of non-traumatic abdominal pain, 120 (58.8%)
were males and 84 (41.2%) females Azeem, 2019. In contrast Ghimire, et al. in
a study aimed to assess the implications of ultrasonography in the diagnosis and
management of patients presenting with non-traumatic acute abdominal pain
reported that there was female predominance with a male to female ratio of
1:1.8 Ghimire, et al., 2018. This difference is understandable as there is
different geographic distribution and epidemiologic factors.
Among the present study population, ureteric calcului were the most
common cause of acute abdomen, accounting for 22% of total cases. The
second commonest cause for acute abdomen was acute cholecystitis and acute
appendicitis (16%). This was followed by intestinal obstruction and perforation
(7%), iliopsoas abscess, pancreatitis (5.5%), splenic infarctions, ectopic
pregnancy and diverticulitis (3.5%). The Least common diagnoses were liver
abscess, ovarian torsion, incarcerated hernia and leaking AAA (1.8%).
In contrast Kumar &Badhan, in their study found that acute appendicitis
was the most common cause of acute abdomen Kumar N & Badhan, 2020).
Also, Malviya, et al. reported that the most common acute non-traumatic
abdominal emergency was acute appendicitis which accounted for 61.71% of

4. the total patients. 10.79% patients presented with acute intestinal obstruction,
followed by hollow viscus perforation and acute cholecystitis i.e., 8.57% and
8.28% respectively.Acute pancreatitis, liver abscess and Meckel's diverticulitis
constituted 3.99%, 3.25% and 1.40% cases, respectively Malviya, et al., 2017.
Panigrahi, et al, found that peptic perforation (both gastric and duodenal
perforation) was the most common cause of acute abdomen (14%). Second most
common cause was acute appendicitis (12.9%). Lowest number of cases was
found in uretericcolic (2.9%) (Panigrahi, et al, 2021). Also, Mandhane &
Mariyappa, in a previous study reported that hollow viscus perforation forms
the commonest cause of acute abdomen. Acute appendicitis being the 2nd and
acute calculus cholecystitis forms the 3rd commonest cause of acute abdomen
Mandhane& Mariyappa, 2019.
These different incidences may be due to the demographic, ethnic and
dietary habits differences between the studies populations.
All the study participants underwent ultrasonography (USG) scanning
then the results were confirmed with final diagnosis. In our study, USG
diagnosis was consistent with final diagnosis in 67.3% of cases (37 patients).
MDCT was done to 43patients (patients except those with acute cholecystitis
and gynecologicl cases). According to a previous study among 248 patients
presented in the radiology departmentfor non-traumatic abdominal pain

5. ultrasound correctly diagnosed and correlated with the final diagnosis in 233
patients (93.9%) Ghimire, et al., 2018.
In our study the sensitivity of US for ureteric calculi was 41.6%, while
sensitivity of CT was 100%. In a previously conducted study non-contrast CT
was found to have 97.2% sensitivity for diagnosis of ureteric calculi, while US
sensitivity had 75.4% Ahmed, et al., 2018.
Wahab, et al. conducted a study to evaluate the diagnostic accuracy of
ultrasound in detecting ureteric stone and it was found that the trans-abdominal
ultrasound was having sensitivity of 69.64% Wahab, et al., 2019. According to
a previous study results the sensitivity of the ultrasound for ureteric calculi was
58.62% Rao, et al., 2020.
In our study there were 12 cases of ureteric calculus, 66.7% cases of them
was mid ureteric stone, 25% was in the intra mural part of lower third of the
ureter and 8.3% with stone in the upper ureter. In a study conducted by Alabi,
et al. it was found that stone location was in the upper ureter in 16.7% of the
cases, mid-ureter in29.2%, and lower ureter in 54.2% Alabi, et al., 2019. This
difference may be due to the small study population in the current study.
The sensitivity of US and CT for cholecystitis was calculated, both were
100%. In agreement with this result Malik, et al, in a study reported that US
had sensitivity ˃95% for diagnosis of cholecystitis (Malik, et al, 2020).

6. In contrast sensitivity of US and CT for cholecystitis was84% and 85.5%,
respectively Kumar & Badhan, 2020. Also, in another study the sensitivity of
CT for detecting acute cholecystitis was significantly greater than that of US:
85% versus 68%, respectively Wertz, et al., 2018.
The previously reported sensitivity of US for cholecystitis is greater than
that seen in our study (41.6%). The decreased sensitivity of US in this study
may be secondary to the different patient population regarding the ethnicity and
other habits. Although gallstones and cholecystitis are more prevalent in the
female population, our study population was composed of mostly men and often
obese patients, potentially leading to poor-quality examinations.
Ultrasonographic features of acute cholecystitis included in the current
study were presence of stones in 77.7% of cases or mud in 22.2% of cases,
increased wall thickening in 88.8%of cases, fluid collection 22.2% of cases and
increased width and length of gall bladder 44.4% of cases.According to a
previous study results The most common finding of acute cholecystitis in the
US group was gallbladder wall thickening (77% of patients) followed by
cholelithiasis (68%) and gallbladder distention (59%) Wertz, et al., 2018 .
Appendicitis cases were assessed. The sensitivity of US and CT were
77.7% and 100%, respectively. Also, in a previous study ultrasound sensitivity
for diagnosis of appendicitis was 73% Samir, et al., 2016.

7. In the present study sensitivity of US for small bowel obstruction was
75%, while that of CT was 100%. Kumar,&Badhan, in a study found that
both US and CT scans had 100% sensitivityfor small bowel obstruction Kumar,
&Badhan, 2020.
As regard US sensitivity in intestinal perforation cases, it was 25%, while
CT had 100% sensitivity. US and CT results in intestinal perforation cases were
assessed in Kumar &Badhan, study and it was found that US and CT had
68.4% and 100%, respectively.
Iliopsoas abscess cases in the present study were assessed by US that was
found to have 66.6%sensitivity and CT that was found to have 100% sensitivity.
In agreement with this result Li, et al. reported that CT is nearly 100% (Li, et
al., 2017). Ultrasound sensitivity in a previous study was higher than that in the
current study in diagnosis of retroperitoneal abscess (90%) Benkhadoura, et
al., 2018 ; Ibrahim,&Abd El AE., 2021.
In the present study sensitivity of US for acute pancreatitis was 33.3%,
while that of CT was 100%. In a previous study US and CT sensitivity for acute
pancreatitis diagnosis was 70.8% and 100%, respectively Kumar, & Badhan,
2020.
According to the current study results both of US and CT had 100%
sensitivity in splenic infarcts cases. In study conducted by Li, et al., it was

8. found that conventional US had 70% sensitivity for diagnosis of splenic infarcts
Li, et al., 2020.
US was not sensitive for acute diverticulitis in the present study. CT had
100% sensitivity. Similarly, a study results showed that CT had 98-99%
sensitivity for acute diverticulitis Thorisson, et al., 2020. A previous study
reported that US had a sensitivity of 84–98%. Sonography has comparable
accuracy with CT, but it is operator dependent and not yet widely used Les, et
al., 2021.
Ectopic pregnancy and ovarian torsion cases were assessed by US and it
was found to have 100% sensitivity. Similar to the current study results, it was
reported that sensitivity of U/S in diagnosis of ectopic pregnancy was 97.3%
Ismail, et al., 2018.
In contrast, Grunau, et al. in a study reported that the Sensitivity of
ultrasound in diagnosing ovarian torsion was 70% Grunau, et al., 2018. In a
previous study US had 77.9% sensitivity for diagnosis of ectopic pregnancy
Salman, et al, 2021.
The present study results showed that CT had 100% sensitivity for
leaking AAA, liver abscess, incarcerated hernia and abdominal malignancy,
while US had no sensitivity for them.

9. Similarly, in a previous study it was found that computed tomography
angiography has excellent sensitivity (approximately 100%) and yields the
added benefit of facilitating surgical planning and management Andrusaitis, &
Peña, 2017.
According to a previous study results CT scanning has a higher
sensitivity (97% sensitive) compared to ultrasound (85% sensitive) for detection
of liver abscess Bächler, et al., 2016. Also, Ruben et al, in a study showed that
Computed tomography is not the first line test for diagnosing liver abscesses,
but it has sensitivity of 95-100% Ruben, et al, 2020.
Simon, in a study reported that CT had ˃90% sensitivity for colorectal
cancer Simon, 2016.
A study conducted by Cerci, et al. revealed that CT and surgical findings
correlated (sensitivity) as follows: uterine and tubal spread (66%), cervical
involvement (100%), peritoneal nodules increased density-carcinomatosis
(57%), omental involvement (68%), retroperitoneal involvement (25%), ascites
(85%), perirectal and perivesical fat plan obliteration (43%), liver metastasis
(50%/91%), small and large bowel involvement (47%), adnexal mass (94%),
and other metastases (47%). Also, CT findings were found to be statistically
insignificant for prediction of mesenteric involvement, bladder metastasis, and
diaphragmatic involvement. The overall CT sensitivity at detecting
intraoperative findings was 91% (Cerci, et al., 2016).

10. In a previously conducted study, it was found that CT had 50% sensitivity
for diagnosis of strangulated hernia Chang, et al., 2017. In another study the
CT sensitivity for bowel obstruction was 89.28% (Rather, et al., 2019).
These different Sensitivity values of CT in the different studies may be
due to the observer bias when the radiologic findings were assessed by a single
radiologist, the relatively low number of available patients and the retrospective
uncontrolled study that is subjected to incomplete data and potential selection
bias.
Conclusion
Given its availability, relatively low cost, and absence of ionizing
radiation or need for contrast materials, US has maintained an important role in
the evaluation of the acute abdomen. CT is a rapid, first-line, imaging modality
with high accuracy in the diagnostic work-up of patients presenting with acute
abdominal pain.
Multi detector CT was found to have higher sensitivity as a differential
diagnostic tool in the cases of acute abdomen. Because of the wide spectrum of
diseases leading to acute abdominal pain, one major advantage of CT is its
ability to suggest alternative diagnoses if the suspected clinical diagnosis is
unconfirmed.

11. Recommendation
The role of multi-detector CT andUltrasonography in the evaluation of
non traumatic acute abdomen need to be further evaluated in a larger sample
size study.
This diagnostic screening method should available in the surgical
emergency department; training programs in sonography an MDCT should be
available for young surgeons for the judgment of abdominal emergency cases.
To recognize gynecological diseases, which simulate appendicitis, US
examination must be considered necessary in a young female patient.

12. Summery
Acute abdomen can represent a wide spectrum of conditions, ranging
from a benign and self-limiting disease to a surgical emergency.
Ultrasound (US) is the preferred imaging modality in children, pregnant
women, and generally young patients, owing to the absence of ionizing
radiation. Advances in computed tomography (CT) with multi-planar
reformations and 3D reconstruction have led to some clinicians considering
multi-detector CT (MDCT) as the modality of choice when evaluating patients
with right iliac fossa pain. The aim of this study was to clarify role of multi
detector CT versus ultrasonography in the evaluation of non traumatic acute
abdomen.
This prospective observational study was performed in Department of
Radio-diagnosis KASR EL-AINY and Hurghada general hospitals. It was
conducted on 55 patients with non traumatic acute abdomen presented to the ED
that were clinically diagnosed acute abdomen. Patients with acute abdominal
pain were evaluated with both ultrasonography and computed tomography.
Ultrasonography was done first followed by computed tomography in
ultrasonography (US) positive cases, in symptomatic patients with negative US
scans and in patients with suboptimal scan.

13. The current study results showed that the mean age among the
participants was 37.4 years ranging from 14 to 82 years. The most common age
group was 15-30 years (41.8 %).Most of the study population were males (67%)
with M: F ratio of 2:1.
Among the present study population, ureteric calcului were the most
common cause of acute abdomen (22%) followed by acute cholecystitis and
acute appendicitis.
All the study participants underwent ultrasonography (USG) scanning
then the results were confirmed with final diagnosis. In our study, USG
diagnosis was consistent with final diagnosis in 67.3% of cases.
In our study the sensitivity of US and CT for ureteric calculi was 41.6%
and 100%, respectively.The sensitivity of US and CT for cholecystitis was
calculated, both were 100%.Ultrasonographic features of acute cholecystitis
included in the current study were presence of stones in 77.7% of cases or mud
in 22.2% of cases, increased wall thickening in 88.8% of cases, fluid collection
22.2% of cases and increased width and length of gall bladder 44.4% of cases.
Appendicitis cases were assessed. The sensitivity of US and CT were
77.7% and 100%, respectively. As regard US sensitivity in intestinal perforation
cases, it was 25%, while CT had 100% sensitivity. Iliopsoas abscess cases in the

14. present study were assessed by US that was found to have 66.6% sensitivity and
CT that was found to have 100% sensitivity.
In the present study sensitivity of US for acute pancreatitis was 33.3%,
while that of CT was 100%.
According to the current study results both of US and CT had 100%
sensitivity in splenic infarcts cases. US was not sensitive for acute diverticulitis
in the present study. CT had 100% sensitivity. Ectopic pregnancy and ovarian
torsion cases were assessed by US and it was found to have 100% sensitivity.
The present study results showed that CT had 100% sensitivity for leaking
AAA, liver abscess, incarcerated hernia and abdominal malignancy, while US
had no sensitivity for them.
We concluded that given its availability, relatively low cost, and absence
of ionizing radiation or need for contrast materials, US has maintained an
important role in the evaluation of the acute abdomen. CT is a rapid, first-line,
imaging modality with high accuracy in the diagnostic work-up of patients
presenting with acute abdominal pain. Multi detector CT was found to have
higher sensitivity as a differential diagnostic tool in the cases of acute abdomen.
Because of the wide spectrum of diseases leading to acute abdominal pain, one
major advantage of CT is its ability to suggest alternative diagnoses if the
suspected clinical diagnosis is unconfirmed. It is recommended that the role of

15. multi-detector CT and Ultrasonography in the evaluation of non traumatic acute
abdomen need to be further evaluated in a larger sample size study.