Renal Vascular Affection in Systemic Sclerosis Patients and Possible Correlation with Peripheral Vascular Involvement Assessed by Nailfold Capillaroscopy.

Background: Symptomatic renal involvement was observed in only 24% of systemic sclerosis (SSc) patients. Objective: We evaluated renal vascular affection, which is linked to disease characteristics and nailfold capillaroscopy (NFC) outcomes in SSc patients. Methods: Fifty SSc individuals were subjected to renal doppler ultrasound, NFC, and evaluation of disease severity utilising the Medsger disease severity scale. Results: The cohort comprised 46 females and 4 males, with a mean age of 33.82 ± 11.19 years. Symptomatic renal affection [proteinuria, elevated creatinine level, and mitigated creatinine clearance, and estimated glomerular filtration rate (eGFR) ± hypertension] was observed in 24% of subjects. However, an elevated renal resistive index (RRI) was detected in 44%. Accordingly, patients were allocated into Group 1 (patients exhibiting normal RRI, n = 28) and Group 2 (patients manifesting raised RRI, n = 22). Group 2 patients experienced significantly older age, prolonged disease duration, raised severity scores, protein/creatinine ratio, and avascular NFC scores (p < 0.05). The RRI demonstrated a positive association with age, disease duration, severity, duration of Raynaud's phenomenon, and avascular scores (p < 0.05), alongside negative correlations with creatinine clearance, eGFR, and capillary density (p < 0.05). The main predictors of high RRI encompassed age > 43 years, disease severity score > 5, protein/creatinine ratio > 0.21, capillary density ≤ 6, and avascular score > 1 (p = 0.05). Conclusion: The RRI detected early asymptomatic renal affection, which correlated positively with age, disease duration, severity, and high NFC avascular scores and negatively with creatinine clearance and eGFR.