Pancreas shrinkage following recurrent acute pancreatitis: an MRI study

Transition from the first attack of acute pancreatitis (AP) to chronic pancreatitis (CP) via recurrent AP is common. Total pancreas volume (TPV) and pancreas diameters are often reduced in advanced CP but have never been studied after AP. The objective of this study was to investigate pancreas size after clinical resolution of AP and its association with the number of AP attacks.

Individuals with a history of AP were grouped based on the number of attacks (1, 2, ≥ 3 attacks). Healthy individuals were also recruited. All participants underwent magnetic resonance imaging, from which TPV and pancreas diameters (across the head, body, and tail) were measured independently by two raters in a blinded fashion. Generalised additive models (including age, sex, body mass index, and glycated haemoglobin levels) were used.

A total of 123 participants were studied. Total pancreas volume and tail diameter were significantly reduced in both unadjusted (TPV (p = 0.036), tail diameter (p = 0.009)) and adjusted (TPV (p = 0.026), tail diameter (p = 0.034)) models in individuals with ≥ 3 attacks, but not with 1 or 2 attacks, compared with healthy individuals. Head and body diameters did not differ significantly.

Reduced TPV and tail diameter characterise individuals after ≥ 3 attacks of AP and may represent one of the earliest irreversible morphological changes in individuals after AP. A high-risk population for transition to CP might include individuals with at least 3 attacks of AP whereas those with less than 3 attacks might be at a low risk.

• A significant reduction in total pancreas volume was demonstrated in individuals after 3 or more attacks of acute pancreatitis (without conventional signs of chronic pancreatitis). • Pancreas tail diameter, but not head or body diameter, was reduced in individuals after 3 or more attacks of acute pancreatitis (without conventional signs of chronic pancreatitis). • The above findings were independent of age, sex, body mass index, and glycated haemoglobin levels.