Diagnostic value of Intermediate Monocytes [CD14+CD16+] in Recent Type 1 Diabetes in Children at Zagazig University Hospital

Background:Type 1 diabetes mellitus (DM1) is caused by autoimmune selective destruction of pancreatic b-cells. As a multifactorial disease, it is caused by a complex combination of genetic and environmental factors triggering autoimmunity. Peripheral blood monocytes are heterogeneous population and until recently were only divided into two subsets based on CD16 expression – CD16 and CD16+. However, minor CD16+ population can be further subdivided into CD14brightCD16+ and CD14dimCD16+ cells. Therefore, there are three distinct subsets of monocytes: the classical CD14brightCD16, the intermediate CD14brightCD16+, and the non-classical CD14dimCD16+. The main objectives of this study were to study the relation between change in intermediate monocyte level and development of recent onset T1D and to determine if level of intermediate monocyte is a predictive factor for poor residual islet cells function determined by level of HA1C, insulin, c-peptide. Methods: This is a case- control study carried out at pediatric endocrinology outpatient clinic and Clinical pathology department of Zagazig university hospital. All studied groups were subjected to full history taking, thorough clinical examination and laboratory investigations included Cell-surface monocyte phenotypic analysis.Results:The most common signs and symptoms of presentation were Acidotic breathing. Dry mouth. Polyuria. Polydepsia. Polyphagia. Wt. loss. DKA occurance. Glucosuria and ketonuria . There was highly significant increase in FBS and HBA1C and highly significant decrease in C. peptide in patient group compared to control group.there was significant increase in absolute count of monocytes and non-significant increase regarding neutrophils and lymphocytes counts in patient group compared to control group.There was highly significant increase in the ratio of classical and intermediate monocytes in T1DM group. While the ratio of non-classical monocytes were non significantly increased in T1DM group compared to control group. Type 1 Diabetes Mellitus patients the CD14+/CD16+monocytes (Intermediate subtype) revealed the highest sensitivity and specificity (75%, 100%) among the other monocytes subtypes as the classical (30%,90%) and the Non classical (5%, 95%). There was highly significant positive correlation between intermediate monocytes ratio and FBS, HbA1C.However, there was significant negative correlation between intermediate monocytes ratio and C-peptide.Conclusion:The intermediate monocyte population was found to be expanded in pediatric patients with T1DM. As these cells were shown to have pro-inflammatory activity, they are likely to be implicated in the impaired function of β−cells, with deleterious consequences for the development of T1DM..