Peripancreatic collections in acute pancreatitis: Correlation between computerized tomography and operative findings

Table 1 Characteristics of the study population

Parameters
Median (IQR) age (yr)	54 (50-67)
Male patients, n (%)	20 (80)
Contrast-enhanced CT, n (%)	23 (92)
Median (IQR) No. of PPCs
Necrosis without pus	2 (1-2)
Necrosis with pus	1 (1-2)
Fluid without necrosis	1 (1-3)
Infected PPC, n (%)	12 (48)
OF in patients with PPC
Total, n (%)	19 (76)
Persistent OF (> 48 h), n (%)	15 (60)
Multiple OF, n (%)	2 (8)
Mortality, n (%)	3 (12)

NB: Two patients in the group with necrosis and pus did not have a contrast injection prior to computed tomography scan due to renal failure. PPC: Peripancreatic collections; OF: Organ failure.

Table 2 Computed tomography characteristics of peripancreatic collections

		Necrosis without pus (n = 25)	Necrosis with pus (n = 16)	Fluid without necrosis (n = 4)	‘P’ value
	Volume in cm3, median (IQR)	193.4 (50-1129)	116.3 (88-389)	551.7 (324-937)
Fluid characteristics	Heterogeneity, n (%)	12 (48)	15 (93.8)c	1 (25)a	0.0041
	Fluid attenuation, n (%)	21 (84)	13 (81.3)	4 (100)	0.69
Wall characteristics	Perceptible, n (%)	23 (92)	14 (88)	4 (100)	0.76
	Enhancing, n (%)	21 (84)	14 (88)	4 (100)	0.68
	Irregular, n (%)	18 (71)	14 (88)	1 (25)a	0.05
	Internal air, n (%)	4 (16)	9 (56)c	0 (0)a	0.0091
	Vessel involvement, n (%)	5 (20)	3 (19)	0 (0)	0.62

NB:

¹Indicates statistically significant value when all groups were compared.

^aP < 0.05 when compared individually with the group with necrosis and pus;

^cP < 0.05 when compared individually with the group with necrosis without pus. Difference between parameters in the group with necrosis without pus and the group with fluid without necrosis were not statistically significant (P > 0.05). Difference in volumes of peripancreatic collections in the three groups were not statistically significant (P > 0.05).

Table 3 Predictive value of heterogeneity and presence of air within necrotic collection on computed tomography scan in diagnosing the presence of pus

	Heterogeneity	Presence of air	Both
Sensitivity (%)	93.8	47.3	47.4
Specificity (%)	52.0	84.0	92.0
Positive predictive value (%)	55.5	69.2	81.8
Negative predictive value (%)	92.9	67.7	23.3
Positive likelihood ratio	1.9	2.9	5.9
Negative likelihood ratio	0.1	0.6	0.6