Background and Aim of work: The aim of the present study is to evaluate serum
YKL-40 levels in patients with type II diabetes with increasing levels of albuminuria,
and to examine a possible correlation to high-sensitivity C-reactive protein (hsCRP)
and insulin resistance in these patients. Methods: The study comprised 125 patients
with type II diabetes attending Diabetes& Endocrinology Unit in Mansoura
Specialized Medical Hospital. They were divided into 3 groups: 39 patients had
normoalbuminuria (urinary albumin excretion rate < 30 mg/24 h), 46 patients had
persistent microalbuminuria (urinary albumin excretion rate 30–300 mg/24 h), and
40 patients had persistent macroalbuminuria/diabetic nephropathy (urinary albumin
excretion rate > 300 mg/24 h). The control group included 35 healthy individuals
with matched age and sex. Serum YKL-40 was measured by sandwich enzyme
immunoassay and serum hsCRP was measured by particle enhanced
immunonephelometry. Insulin resistance was assessed using Homeostasis Model
Assessment index for Insulin Resistance (HOMA-IR). Results: Mean serum YKL-40
level was 38.48ng/ml, 75.33ng/ml, 116.87ng/ml and 146.43ng/ml in control, normo- ,
micro- and macroalbuminuria groups respectively. Serum YKL-40 levels were
significantly elevated in the three diabetic groups versus control group (P < 0.001 for
each group). Also, YKL 40 was correlated with hsCRP and HOMA-IR (r = 0.746, P <
0.001 & r = 0.792, P < 0.001, respectively) in the total group of participants. ROC
curve analysis showed that YKL-40 is a good marker to discriminate between patients
with and without albuminuria with sensitivity 93% and specificity of 88%.
Conclusion: It could be concluded that YKL-40, is a marker of inflammation and
endothelial dysfunction. It is elevated in patients with type II diabetes with marked
elevation in patients with macroalbuminuria/ nephropathy. These results suggest a
role for YKL-40 in the gradually progressing vascular complications in patients with
diabetes, with YKL-40 being a possible early and good marker of renal affection. It
seems to be useful for screening because it is detectable in early stages and
subclinical diseases.