Growth arrest-specific protein 6 as a marker of nephritis in systemic sclerosis and juvenile systemic lupus erythematosus patients.

Background: Renal impairments commonly occur as a complication of autoimmune connective tissue diseases (CTDs). Therefore, early nephritis prediction is vital for patient outcomes. Growth Arrest-Specific Protein 6 (GAS6) was found to be upregulated in many types of inflammatory renal disease, including diabetic nephropathy.Aim: To evaluate GAS6 as a predictor of renal impairment in adults with systemic sclerosis (SSc) and children with systemic lupus Erythematosus (SLE).Methods: The study included 60 patients with SSc and 40 children with SLE. The serum level of GAS6 was measured using the ELISA technique. In adults with SSc, total proteins in 24-h urine concentration of >300 mg/24 h indicated renal inflammation, while in children with SLE, nephritis was diagnosed by abnormal renal pathology.Results: In SSc patients, GAS6 significantly increased in patients with proteinuria. GAS6 is an independent predictor of nephritis with an odds ratio (OR) of 1.06 and a 95% confidence interval (CI) of 1.0-1.1. at cutoff 12.2 ng/mL GAS6 predicted proteinuria with sensitivity 86.7% (95% CI: 59.5% to 98.3%), specificity 57.8% (95% CI: 42.1% to 72.3%), positive predictive value 40.6% (95% CI: 31.5% to 50.4%), negative predictive value 92.9% (95% CI: 77.7% to 97.73%), and accuracy 65.0% (95% CI: 51.6% to 76.9%). In SLE patients, Serum GAS6 did not differ significantly between children with and without lupus nephritis.Conclusion: GAS6 is an independent predictor of nephritis in patients with SSc. However, there is no association between GAS6 and nephritis in juvenile patients with SLE.

Matrix metalloproteinase-9 in pediatric rheumatic heart disease with and without heart failure.

In cardiovascular disorders, the myocardium may be subjected to the breakdown and remodeling of collagen by metalloproteinase-9 (MMP-9). We hypothesized that the serum MMP-9 concentration may be elevated in pediatric patients with rheumatic heart disease (RHD) and heart failure (HF), and its level can be correlated with the HF severity. Thus, in the present study, we aimed to evaluate the sensitivity and accuracy of MMP-9 to predict HF in children with RHD and to determine its effectiveness as an indicator of the degree of HF. This study included 98 consecutive children admitted to the Department of Pediatrics, Zagazig University Hospital, Al Sharqia Governorate, Egypt with newly diagnosed RHD. Their ages ranged from 8.5 to 16 years. Fifty-eight children had RHD without HF while 40 children were complicated with HF which was diagnosed clinically and by echocardiography. A total of 44 healthy children were enrolled as a control group. MMP-9 serum levels were estimated by enzyme-linked immunosorbent assay. The serum MMP-9 concentration was higher in the RHD without HF and RHD with HF groups than this level noted in the control (P<0.001). MMP-9 was a significant predictor of HF; area under the curve (AUC)=0.85 [95% confidence interval (CI), 0.76-0.94]. At the level of 386.9 ng/ml, MMP-9 detected HF with a sensitivity 95% (95% CI, 83.08-99.39), specificity 74.14% (95% CI, 60.96-84.74), positive predictive value 71.70% (95% CI, 61.96-79.75), negative predictive value 95.56% (95% CI, 84.67-98.82) and accuracy 82.65% (95% CI, 73.69-89.56). In addition, MMP-9 showed a significant negative correlation with ejection fraction and fractional shortening (P=0.01 and P=0.02, respectively). In conclusion; MMP-9 may be an independent sensitive marker with which to detect HF in children with RHD and it can predict the prognoses of these patients as it correlates with the severity of HF. Further studies considering MMP-9 in the detection of 'silent' RHD in school aged children and asymptomatic HF in children with known RHD especially in rural areas, are highly recommended.