Kidney Week

Abstract: FR-PO1117

Histopathological Findings in Mixed Connective Tissue Disease with Renal Involvement

Session Information

• Glomerular Diseases: Clinical, Outcomes, Trials - II
  October 26, 2018 | Location: Exhibit Hall, San Diego Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Glomerular Diseases

• 1203 Glomerular Diseases: Clinical, Outcomes, and Trials

Authors

• Ramirez, Silvia, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Mexico City, Mexico

Silvia Ramirez,

• Morales-Buenrostro, Luis E., Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Mexico City, Mexico

Luis E. Morales-Buenrostro,

• Correa-Rotter, Ricardo, Institutor Nacional de la Nutricion, Mexico City, Mexico

Ricardo Correa-Rotter,

• Martin, Eduardo, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Mexico City, Mexico

Eduardo Martin,

• Uribe-uribe, Norma O., Instituto Nacional de Ciencias Medicas y Nutricion, "Salvador Zubiran", Mexico City, Mexico

Norma O. Uribe-uribe,

• Cardenas, Laura, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Mexico City, Mexico

Laura Cardenas,

• Reyes, Montserrat, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Mexico City, Mexico

Montserrat Reyes,

• Rodriguez, Tatiana Sofía, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran, Mexico City, Mexico

Tatiana Sofía Rodriguez,

Background

Renal involvement in mixed connective tissue disease (MCTD) is uncommon and present in up to 20% of patients, most commonly, an immune-complex nephropathy. The aim of the study was to identify the prevalence of renal involvement and describe renal histophatological findings in MCTD.

Methods

Single center retrospective cohort of MCTD (2003-2017) according to the Alarcón-Segovia criteria, assessed to identify cases with renal involvement. Histological findings of biopsied patients are described.

Results

131 MCTD patients were identified, of which 14 (10.7%) had renal involvement, 7 underwent a renal biopsy, 6/7 were women; mean age at onset of renal involvement 47.1 ± 7.5 years. Most frequent extra-renal clinical manifestations were: Raynaud’s phenomenon and arthritis, both in 7 (100%), puffy hands in 6 (85.7%), sclerodactily in 5 (71.4%), myositis in 5 (71.4%), and interstitial lung disease in 3 (42.8%). Median time elapsed from MCTD diagnosis to renal involvement was 82 (2-208) months. Four (57.1%) presented with sub-nephrotic proteinuria, 3 (42.8%) with nephrotic range proteinuria and 3 (42.8%) with CKD-EPI eGFR <60ml/min/1.73m². Histological diagnoses: pauci-immune focal necrotizing and crescentic glomerulonephritis (GN) (2 pts; one developed positive ANCA antibodies), lupus nephritis (LN) class III + V ISN/RPS 2003 (1), LN class IV ISN/RPS 2003 with thrombotic microangiopathy (1), non-LN membranous GN (2) and minimal mesangioproliferative GN (1). Six (85.7%) achieved either total or partial remission at a median follow up of 61 (1-363) months with combination of steroids and other immunosuppressant. No patient required renal replacement treatment.

Conclusion

In our cohort of MCTD, prevalence of renal involvement was low. Renal biopsy demonstrated a diversity of histological patterns: glomerulonephritis, vasculopathy, and overlap with ANCA associated vasculitis; these options should be considered in the differential diagnoses of MCTD patients with renal involvement.