Kidney Week

Abstract: PO1446

Serum and Glomerular Complement Components as Biomarkers in the First South Asian Prospective Longitudinal Observational IgA Nephropathy Cohort (GRACE-IgANI)

Session Information

• Glomerular Diseases: Immunology and Inflammation in IgANP, C3GP, TMA, and Nephrotic Diseases
  November 04, 2021 | Location: On-Demand, Virtual Only
  Abstract Time: 10:00 AM - 12:00 PM

Category: Glomerular Diseases

• 1202 Glomerular Diseases: Immunology and Inflammation

Authors

• Alexander, Suceena, Christian Medical College Vellore, Vellore, Tamil Nadu, India

Suceena Alexander, MD, MBBS, FASN

• Varughese, Santosh, Christian Medical College Vellore, Vellore, Tamil Nadu, India

Santosh Varughese,

• Thomas, Athul, Christian Medical College Vellore, Vellore, Tamil Nadu, India

Athul Thomas,

• Eapen, Jeethu Joseph, Christian Medical College Vellore, Vellore, Tamil Nadu, India

Jeethu Joseph Eapen,

• John, Elenjickal Elias, Christian Medical College Vellore, Vellore, Tamil Nadu, India

Elenjickal Elias John,

• Valson, Anna T., Christian Medical College Vellore, Vellore, Tamil Nadu, India

Anna T. Valson,

• David, Vinoi George, Christian Medical College Vellore, Vellore, Tamil Nadu, India

Vinoi George David,

• Feehally, John, University of Leicester, Leicester, Leicestershire, United Kingdom

John Feehally,

• Barratt, Jonathan, University of Leicester College of Life Sciences, Leicester, Leicester, United Kingdom

Jonathan Barratt,

• John, George, Christian Medical College Vellore, Vellore, Tamil Nadu, India

George John,

• Seelen, Marc Maj, Universitair Medisch Centrum Groningen, Groningen, Groningen, Netherlands

Marc Maj Seelen,

• Daha, Mohamed R., Universitair Medisch Centrum Groningen, Groningen, Groningen, Netherlands

Mohamed R. Daha,

Background

The Glomerular Research And Clinical Experiments- IgA Nephropathy in Indians is a prospective longitudinal cohort . The study protocol has been published and is registered with WHO trial id: ISRCTN36834159. The role of serum and glomerular complement components in South Asian IgAN is unknown.

Methods

201 consenting adult IgAN patients were consecutively recruited post kidney biopsy. 192 (97%) patients completed 3 years. Serum complement C3 and C4 levels and glomerular C3d, C4d and C5b-9 by IHC were quantified at baseline in IgAN patients. Composite outcome (CO) was defined as ≥50% fall in eGFR from baseline and/or eGFR <15ml/min/1.73m² or RRT/death.

Results

195 patients (97%) completed 3 year longitudinal follow-up. Lower serum C3 was significantly associated with S1, T1/T2 according to the Oxford MEST grading and with global glomerulosclerosis (GS>33%) whereas higher C4 levels were associated S1 scores. Increased mesangial C3d deposition correlated with increased mean arterial pressure, proteinuria, decreased serum albumin, decreased eGFR and with GS>33%. Similar to C3d, increased mesangial C4d correlated with increased systolic blood pressure, decreased serum protein and decreased eGFR and with GS>33%. Mesangial deposition of C5b-9 did not have any clinical associations. Lower serum C3, higher serum C4 and incrased mesangial C3d was significantly associated with CO over three years.

Conclusion

Serum and tissue complements could be potential biomarkers for severity and progression n the GRACE-IgANI cohort. This requires furhter validation.

Associations with clinical variables

Funding

• Government Support – Non-U.S.