Case 24: Young male with C3 glomerulopathy and collapsing FSGS
To preserve patient privacy and for didactic purposes, case descriptions and pathology reports have been anonymized and partially fictionalized. The pathology images are representative images from a mixture of similar cases.
Jonathan SlaterCase Presenter | Baystate Medical Center, Springfield, MA, USA | No conflict of interest reported
Mihran NaljayanNephrology Discussant | Louisiana State University Health Sciences Center, New Orleans, LA, USA | No conflict of interest reported
Vanesa BijolNephropathology Discussant | Brigham and Women's Hospital, Boston, MA, USA | No conflict of interest reported
Patient is a 25-year-old male with hypertension and nephrotic range proteinuria identified approximately one year prior to current presentation.
Medical history: Hypertension Hyperlipidemia Obesity Ankle fracture due to motor vehicle accident
Family history: Positive for hypertension in father, and cerebrovascular accident involving his mother.
Medications: Simvastatin Lisinopril
Physical Exam: BMI: 33.3 Blood Pressure: 118/78 mm Hg No rash, ulcers, or joint effusion. Unremarkable otherwise
Laboratory and other data: BUN 12 Creatinine 1.1 Potassium 3.8 Bicarbonate 25 Calcium 9 Phosphorous 3.8 Albumin 4 Hemoglobin 16 Total cholesterol 170 LDL 90 Infectious and serological workup unrevealing. Urinary albumin to creatinine ratio >6000 mg/g
Short term follow up: Interim history: Enrollment into research protocol for the study of genetic or acquired forms of C3 GN was considered, however, he did not meet inclusion criteria and the various differentials were debated, including post-infectious versus C3 glomerulopathy. Workup negative, including HIV, hepB/C, Parvo-virus, no IVDU, no suspicious drugs or medications.
Pathology images pending
First biopsy ~6 months prior to current presentation: Collapsing FSGS. Question raised of ischemic glomerular injury vs. toxin/vasospastic type disease; additionally, isolated C3 deposition suggestive of post infectious GN vs. possibly of C3 Glomerulopathy.
Repeat biopsy ~ months later, at current presentation: Preliminary verbal report: worsening glomerulosclerosis; scattered collapsing FSGS of ischemic pattern, C3G deposits with mesangio-proliferative pattern.
Questions posed & summary of key discussion points
1. What is the possible underlying cause of this patient’s C3 deposits? 2. What is the differential (and significance) for the collapsing FSGS? 3. Would testing for mutations in the alternative pathway components be helpful? And how would this change your management?
Author(s) of case summary:
Case summary pending
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