Abstract: TH-PO525
Collagen Glomerulopathy – A Rare Entity
Session Information
- Trainee Case Reports - I
October 25, 2018 | Location: Exhibit Hall, San Diego Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Trainee Case Reports
- 1203 Glomerular Diseases: Clinical, Outcomes, and Trials
Authors
- Guruswamy sangameswaran, Kothai divya, OU -Tulsa School of Community Medicine, Tulsa, Oklahoma, United States
- Baradhi, Krishna M., OU -Tulsa School of Community Medicine, Tulsa, Oklahoma, United States
Group or Team Name
- OU Tulsa
Introduction
Collagen glomerulopathy (CG) is a rare, non-immunoglobulin deposition disease of unknown etiology, first reported by Arakawa et al in 1979. CG is characterized by agglomeration of atypical type III collagen fibrils in mesangial matrix and subendothelial space. CG is a rare entity, with most of the cases reported from Japan. We describe one such rare case of CG seen in a pediatric patient and emphasize its clinical significance.
Case Description
A 7-year-old Hispanic girl presented with intermittent hematuria and foamy urine since few weeks. She had no family history of renal disease. Patient was normotensive with mild pedal edema and specifically no nail or patellar dysplasia. Labs revealed serum creatinine of 0.44 mg/dl, albumin of 3.3 g/dl, hyperlipidemia and normal complement levels. Urinalysis confirmed hematuria with 2.6 gm of proteinuria on quantification. Renal ultrasound was unremarkable. A diagnostic renal biopsy conducted revealed widespread foot process effacement and nodular mesangial deposits suggestive of collagen III glomerulopathy. She was managed conservatively with angiotensin converting enzyme inhibitors with partial remission of proteinuria.
Discussion
Type III collagen is a structural protein that is normally absent in the glomerulus. Abnormal accumulation of type III collagen in the mesangium and sub-endothelial space leads to proteinuria. Electron microscopy showing mesangial deposits of large (43-65 nm) whorled fibrils is essential for definitive diagnosis. This is distinguished from nail-patella syndrome by the absence of collagen III accumulation in lamina densa of basement membranes.
CG typically presents with hypertension, edema, proteinuria and progressive kidney disease. Familial occurrence with autosomal recessive inheritance has been described. The etiopathogenesis remains elusive, but is associated with factor H deficiency and Hemolytic uremic syndrome. Supportive therapy with control of hypertension and edema is recommended. Role of corticosteroids is unclear. Among patients who received a transplant, none have shown disease recurrence. Our case represents only the second case of CG published from the US. Clinicians should be cognizant of this rare entity and differentiate it from other fibrillary disorders as treatment is supportive rather than the toxic immunosuppressive therapy.