Focal segmental glomerulosclerosis (FSGS) is a histologic description of a glomerular lesion that is associated with significant proteinuria and the nephrotic syndrome. This pathologic finding can be the result of systemic disorders (termed "secondary" causes of FSGS) or may represent primary disease.
Primary FSGS is itself a heterogeneous disease, likely with multiple pathogenic mechanisms resulting in a similar histologic pattern of injury. Secondary causes include chronic reflux nephropathy, chronic hypertension, and obesity.
Clinical presentations vary widely, but typically individuals with primary FSGS present with the nephrotic syndrome. Secondary FSGS is typically associated with less severe proteinuria, often without hypoalbuminemia or peripheral edema. Patients may require renal transplantation, which may have a high frequency of failure from recurrence of FSGS. An early trial of the small-molecule drug inaxaplin significantly reduced proteinuria for patients with apolipoprotein L1 (APOL1) risk variants G1 and G2, which commonly occur in people descended from sub-Saharan Africa. Studies are ongoing.
Focal segmental glomerulosclerosis
Alerts and Notices
Important News & Links
Synopsis

Codes
ICD10CM:
N26.9 – Renal sclerosis, unspecified
SNOMEDCT:
236403004 – Focal Segmental Glomerulosclerosis
N26.9 – Renal sclerosis, unspecified
SNOMEDCT:
236403004 – Focal Segmental Glomerulosclerosis
Differential Diagnosis & Pitfalls
Differential diagnosis of nephrotic range proteinuria:
- Minimal-change disease – sometimes can be very difficult to distinguish from early FSGS, but if Ki67 stain is completed and is positive, this is specific for FSGS
- Membranous nephropathy
- Diabetic glomerulosclerosis (see diabetic nephropathy)
- Lupus nephritis Class V (see systemic lupus erythematosus)
- Renal amyloidosis (AL amyloidosis, AA amyloidosis)
- Light-chain deposition disease
- IgA nephropathy (less common presentation)
- Membranoproliferative glomerulonephritis (less common presentation)
- Fibrillary glomerulonephritis (rare)
- Immunotactoid glomerulonephritis (rare)
- Fabry disease (rare presentation of a rare disease)
Best Tests
Subscription Required
Drug Reaction Data
Below is a list of drugs with literature evidence indicating an adverse association with this diagnosis. The list is continually updated through ongoing research and new medication approvals. Click on Citations to sort by number of citations or click on Medication to sort the medications alphabetically.
Subscription Required
References
Subscription Required
Last Updated:03/27/2023