Gradient-echo magnetic resonance imaging study of pancreatic iron overload in young Egyptian beta-thalassemia major patients and effect of splenectomy

Abstract

BackgroundThalassemic patients suffer from diabetes mellitus secondary to hemosiderosis.AimsThe study aimed to evaluate pancreatic iron overload by T2*-weighted Gradient-echo magnetic resonance imaging (MRI) in young beta-thalassemia major patients and to correlate it with glucose disturbances, hepatic hemosiderosis, serum ferritin and splenectomy.MethodsForty thalassemic patients (20 non diabetic, 10 diabetic, and 10 with impaired glucose tolerance) were recruited from Pediatric Hematology Clinic, in addition to 20 healthy controls. All patients underwent clinical assessment and laboratory investigations included complete blood count, liver function tests, serum ferritin and oral glucose tolerance test (OGTT). A T2*-weighted gradient-echo sequence MRI was performed with 1.5 T scanner and signal intensity ratio (SIR) of the liver and the pancreas to noise were calculated.ResultsSignificant reduction in signal intensity ratio (SIR) of the liver and the pancreas was shown in thalassemic patients compared to controls (P < 0.0001), Thalassemic patients with abnormal glucose tolerance; including diabetics and thalassemics with impaired glucose tolerance; displayed a higher degree of pancreatic and hepatic siderosis compared to thalassemics with normal glucose tolerance or controls (P < 0.001, P < 0.0001). Splenectomized thalassemic patients had significantly lower SIR of pancreas compared to non splenectomized patients (P < 0.05). A strong correlation was present between hepatic and pancreatic siderosis in studied patients (P < 0.001).Conclusionspancreatic siderosis can be detected by T2* gradient-echo MRI since childhood in thalassemic patients, and is more evident in patients with abnormal glucose tolerance. After splenectomy, iron deposition may be accelerated in the pancreas. Follow up of thalassemic patients using pancreatic MRI together with intensive chelation therapy may help to prevent the development of overt diabetes.

Assessment of Hepatic and Pancreatic Iron Overload in Pediatric Beta-Thalassemic Major Patients by Weighted Gradient Echo Magnetic Resonance Imaging

“…Our study also detected lower signal intensity of the liver and pancreas in thalassemic patients with abnormal glucose tolerance (including groups B and C) compared to patients with normal glucose tolerance (group A) in agreement with Matter et al, 2010 [16]. …”

“…In the present study, there is significantly lower signal intensity of the liver (45/50) and pancreas (21/50) in thalassemic patients compared to controls on T2*GRE images and in the in-phase sequence in consistency with Matter et al, 2010 [16]. The pancreatic siderosis that resulted in drop of MR signal intensity subsequent to iron overload occurred in 42% of our patients whereas higher percentage was reported by Noetzli et al, 2009 [17], who reported that iron overload in the pancreas occurs in up to 75–100% of thalassemic major cases.…”

“…This finding was explained by the study made by Matter et al, 2010 [16], by decreased extrahepatic iron buffering capacity in splenectomized patients with accelerated iron deposition in the liver and pancreas.…”

Pancreatic Functions in Adolescents with Beta Thalassemia Major Could Predict Cardiac and Hepatic Iron Loading: Relation to T2-Star (T2*) Magnetic Resonance Imaging

“…In our study, the diagnosis of hepatic siderosis was found in 60% of patients and a significant correlation was found between hepatic T2* and serum ferritin, which was in concordance with previous published studies3 42 53 54 but contradicted others 4…”

Diabetes Mellitus and Impaired Glucose Tolerance in β-Thalassaemia Major Patients with Secondary Haemchromatosis: Frequency and their Associations from a Developing Country

“…Among these endocrine abnormalities, impaired glucose tolerance and diabetes mellitus are the major endocrinopathy which occurs due to transfusion related haemosiderosis and is found in 9-15% of patients with beta-thalassaemia worldwide, accounting for significant morbidity [9][10][11]. DM in thalassaemia patients is a distinct form of DM.…”