Focal Segmental Glomerulosclerosis

Excerpt

Focal segmental glomerular sclerosis (FSGS) is a frequently encountered cause of nephrotic syndrome, accounting for 40% of cases in adults and 20% in children. In FSGS, some (not all) glomeruli are sclerosed (focal), and each involved glomerulus is only partially affected (segmental). FSGS is one of the commonest causes of primary glomerulopathy in adults. FSGS can be broadly classified into primary (no known cause) or secondary. Causes of secondary FSGS include infections, drugs, hemodynamic adaptations in the kidney, and genetics.

Although clinical signs are suggestive, the confirmation of the diagnosis of FSGS is achieved only by histopathology findings. Histologically, it is characterized by segmental scarring involving a part of the glomerulus. It affects some but not all glomeruli sampled. Recent research has shed light on the pathogenesis of FSGS, which is podocyte injury and damage, leading to protein loss and subsequent development of focal sclerosing lesions. Categorizing FSGS into primary and secondary forms carries prognostic and therapeutic implications.

The most common clinical manifestation of FSGS (in over 70% of patients) is nephrotic syndrome, presenting as generalized or dependent edema, fatigue, and appetite loss. Hypertension is another common feature and could be severe, with diastolic blood pressure over 120 mmHg; this is common in patients of Afro-Caribbean origin, particularly those with kidney insufficiency.