Assessment of acute pancreatitis using the CT severity index and modi ed CT severity index

Assessment of acute pancreatitis using the CT severity index and modi ed CT severity index Ahmed A.1*, Ahemad T.2, Ahmed M.3 DOI: https://doi.org/10.17511/tjri.2020.i02.01 1* Atik Ahmed, Associate Professor, Al Ameen Medical College, Bijapur, Karnataka, India. 2 Toufik Ahemad, Junior Resident, Navodaya Medical College, Raichur, Karnataka, India. 3 Mustak Ahmed, Junior Resident, Al Ameen Medical College, Bijapur, Karnataka, India.


Introduction
Acute pancreatitis (AP) is one of the most common gastrointestinal causes for hospitalization in India.
Despite recent advances in medicine, pancreatitis continues to be associated with substantial morbidity and mortality [1]. The most common cause of acute pancreatitis is gallstones/biliary related, followed closely by alcohol use [2]. imaging modalities and interventions, Acute pancreatitis continues to have significant morbidity and mortality that has largely remained unchanged over time [6]. The overall mortality rate is 5% to 17% in severe Acute pancreatitis, and 1.5% in mild Acute pancreatitis [7].
Computed tomography is the gold standard technique not only for its global picture of the pathology and complications but also for the noninvasive method of evaluating the morphology of pancreas and peripancreatic regions in an acute situation. It is unaffected by bowel gas distension and obesity, which is a definite disadvantage on ultra-sonographic evaluation [8].
Contrast material enhanced computed tomography helps in early diagnosis and staging of severity of acute pancreatitis and its complications which helps in the prediction of prognosis of the disease.
As early treatment of patients with severe acute pancreatitis can reduce morbidity and mortality.

Inclusion criteria
A clinically suspected case of acute pancreatitis of all ages.

Exclusion criteria
Equipment used in the study -Siemens Somatom Sensation MDCT 40 slice and Mederton Inkjeterton CT2 (pressure injector).

Statistical analysis
Data analysis was done using SPSS version 25th Data transformation by recording, counting and cross-tabulation was performed and obtained information was processed using Pearson chi-square and Fisher's-exact test.

Results
Total of 70 cases of acute pancreatitis cases was included in the study. These patients underwent CT abdomen and pelvis, later images were reviewed by a radiologist.   Cholelithiasis was found to be the most common aetiological factor for acute pancreatitis in 47.1% of cases followed by alcoholic pancreatitis was seen in 30% of cases.
Together cholelithiasis and alcoholism accounted for 77.1% of cases. Least Aetiological factor such as Trauma and drug-induced.

Extra-Pancreatic Complications
In Tropical Journal of Radiology and Imaging 2020;2(4) Left pleural effusion was more common than the right, and in none of the cases, isolated right-sided pleural effusion was found.
Ascites was the second most common complication seen in 17 patients (24.2%). Among vascular complications, venous thrombosis was the most common (2 in the portal vein and 1 in splenic vein).
One case of pseudoaneurysm was found, both in the splenic artery. More than one complication was present in a few cases.    were also significantly associated with severe grade.  [15]. Peripancreatic inflammatory changes were the most common CT findings seen in 88% of the cases of acute pancreatitis. Mendez et al. found that out of 32 patients, 28 (87.5%) exhibited extrapancreatic spread of the inflammatory process [16].
In the present study, 14 (20%) patients found left pleural effusion to be the most common abnormality which is similar to the other study [17]. Ascites was found to be present in 17 patients (24.2%) in the present study. Venous thrombosis was seen in 3 patients (4.2%). Irshad Ahmad Banday et al., in their study, found ascites to be the second most Balthazar et al., have also reported similar incidence [19].
In the present study, the possible explanation for this is the large number of patients having mild pancreatitis in their study group. Using the currently accepted Balthazar CTSI, the severity of acute pancreatitis was graded as mild (score of 0-3) in 29 (41.4%) cases, moderate (score of 4-6) in 19 (27.1%) and severe (score of 7-10) in 22 (31.4%) patients. Using the modified CTSI scoring, maximum number 28 (40.0%) of the patients had severe (score of 7-10) pancreatitis.
Mild (score of 0-3) and moderate (score of 4-6) pancreatitis were categorized in 16  According to Balthazar CT severity index, amongst the patients with mild pancreatitis (n=29), the average duration of hospital stay was 14 days). In the moderate group pancreatitis group (n=19), the average duration of hospital stay was 22 days. In the severe group (n=22), the average duration of hospital stay was 24 days. Modified CT scoring system correctly predicted the outcome in all the patients who had a shift in their severity grades than Balthazar CTSI. The change in severity scoring was seen mainly due to the presence of extrapancreatic complication.
The strong relationship between the Modified CT severity index and the patient outcome in this study correlates with the findings of Mortele et al., [10] Similar trends in duration of hospital stay, intervention or surgery, evidence of infection and organ failure in patients with variable grades of severity of pancreatitis were observed in the present study as that seen by Mortele in their study. This also correlated with the study by Irshad Ahmad Banday et al., which concluded that the Modified CT Severity Index is a simpler scoring tool and more accurate than the Balthazar CT Severity Index [15].
Results of the present study were also found similar to a study conducted by Shivanand Melkundi et al., which showed a significant correlation of grades of severity of acute pancreatitis based on MCTSI with patient outcome parameters than grades of severity of acute pancreatitis based on CTSI [20].
Patient outcome using currently accepted Baltazar CTSI (N=70) showed intervention and length of stay was maximum with mild grade. Infection, organ system failure was significantly associated with severe grade. Whereas with Modified Mortele CTSI (N=70) the average duration of hospital stay was significantly more with severe grade and organ system failure was significantly associated with severe grade.
Similarly, a study shows, the patient outcome in terms of organ failure is more accurately assessed by revised Atlanta classification in comparison with Balthazar and modified CT severity index. The revised classification seems to be a good predictor for clinical outcome of AP Shyu JY et al [21].

Limitations
The sample size was small which may have affected the result. In patients of deranging renal function and pregnant patients contrast CT is contraindicated. The repeated follow-up study was not possible due to cost and radiation exposure. Different treatments were given to patients which changed the patient outcome. However, in the first week, only clinical parameters are useful.

Conclusion
Contrast-enhanced Computed Tomography is an excellent diagnostic modality to stage the severity of the inflammatory process, detect the pancreatic necrosis and depict local complications and grading of severity of acute pancreatitis.
What does the study add to the existing knowledge?
The scores obtained with the modified Mortele index showed a stronger correlation for all outcome parameters in all the patients better than the Balthazar index. Revised Atlanta classification is more accurate than the modified Mortele index and Balthazar severity index for assessing patient mortality and organ failure.