Serum and urinary levels of tumor necrosis factor-alpha and interferon-gamma in diabetic nephropathy patients: a systematic review

ObjectiveIn this systematic review, we determined the association of selected inflammatory cytokines in blood and urine with diabetic nephropathy (DN).MethodsA literature search using the key terms "tumor necrosis factor-alpha," "interferon-gamma," and "diabetic nephropathy" was conducted in PubMed from December 2020 to January 2021. Relevant findings from these studies were collated for qualitative synthesis.ResultsBased on the synthesis of results, TNF-alpha and IFN-gamma levels were consistently higher among DN patients than T2DM patients with no renal complications and healthy individuals. A negative correlation with the estimated glomerular filtration rate (eGFR) and a positive correlation with the albumin-to-creatinine ratio (ACR) were also noted by most studies which assessed their relationship with renal markers.ConclusionThe findings of this systematic review suggest the association of serum and urinary TNF-alpha and IFN-gamma levels with diabetic nephropathy. However, further studies must be conducted to confirm these findings.