Clinical immunology
Relationship between serum levels of tumor necrosis factor-alpha and interleukin-6 in diabetes mellitus type 1 children

It has been documented that the tumor necrosis factor α (TNF-α) serum level correlates with the severity of diabetic retinopathy. No data, however, is available on its presence in an earlier phase of this complication. The aim of our paper was to find out whether a detection of TNF-α serum level in children with Type 1 diabetes mellitus (DM) may be a useful marker of diabetic retinopathy (DR). Eighty seven children with type 1 DM were categorized into two groups: those with diabetic retinopathy and without retinopathy. The levels of TNF-α and interleukin-6 (IL-6) were measured in the serum. The children with DR were older and demonstrated a significantly longer duration of the disease in addition to a higher HbA1c values, albumin excretion rate, C reactive protein and HDL-cholesterol levels as well as the systolic blood pressure than those without retinopathy. The logistic regression revealed that the risk of DR was strongly dependent on TNF-α {(OR 4.01; 95%CI 2.01-7.96) p=0.0001}. Other inflammatory mediators were also indicators of retinopathy, though with less power: CRP {(OR 2.59; 95%CI 1.56-4.30) p=0.0001} and IL-6 {(OR 1.81; 95%CI 1.26-2.59) p=0.001}. An elevated level of TNF-α serum may be a marker of diabetic retinopathy in DM children. Our study implies that DM children who did not progress into retinopathy yet but have detectable serum level of TNF-α should be provided with careful ophthalmologic control.