Serum allograft inflammatory factor-1 concentration in type 2 diabetes mellitus and its relation to the pathogenesis and progression of diabetic nephropathy

Objective
Inflammatory mechanisms may play a pivotal role in diabetic nephropathy (DN). Allograft inflammatory factor-1 (AIF-1), a marker of activated macrophage, may have a role in the progression of DN.
Aim
The aim of the present study was to examine the relationship between serum AIF-1 concentration and parameters of DN.
Patients and methods
A total of 80 type 2 diabetes patients and 20 healthy volunteers (control group) were included in the present study. Patients with renal dysfunction or inflammatory conditions were excluded. Clinical and laboratory tests for patients and controls were carried out. The patients' group was classified according to the Urinary Albumin Excretion (UAE) level into the following: group IA (normoalbuminuria group), which included 30 patients with UAE less than 30 mg/g of creatinine (mg/g Cr); group IIA (microalbuminuria group), which comprised 25 patients with UAE from 30 to 300 mg/g Cr; and group IIIA (macroalbuminuria group), which included 25 patients with UAE greater than 300 mg/g Cr. All patients were subjected to further classification according to estimated glomerular filtration rate (eGFR) into the following: group IB, which included 31 patients with eGFR less than or equal to 60 ml/min/1.73 m; and group IIB, which included 49 patients with eGFR greater than 60 ml/min/1.73 m.
Results
AIF-1 was significantly raised in all patients compared with controls ( = 0.001), and in both group IIA and group IIIA than in group IA ( = 0.001). AIF-1 had significant positive correlation with age, diabetes duration, UAE, log urinary albumin creatinine (A/C) ratio, urea, creatinine, and Fasting Blood Sugar (FBS) ( < 0.001). AIF-1 concentration was inversely correlated with eGFR. Serum AIF-1 was significantly raised in group IB (112.35 ± 26.8) compared with group IIB (83.41 ± 26.23) ( < 0.001). Serum AIF-1 was significantly raised in both groups of simple and proliferative diabetic retinopathy than in the group of nondiabetic retinopathy ( = 0.001).
Conclusion
AIF-1 was significantly raised in type 2 diabetic patients and in those with DN and retinopathy, which may raise a possibility of their pathogenesis as an inflammatory process.