Madam, the incidence and prevalence of idiopathic FSGS is on the rise through out the world.1-4 We have earlier reported FSGS as the commonest cause of idiopathic nephrotic syndrome in adults in Pakistan.4 Idiopathic FSGS is a heterogenous disorder with differences in clinical presentation, prognosis and response to treatment in different patients. Recently attempts have been made concerning pathological classification of FSGS for diagnostic and prognostic purposes.5 One of the pathological variants of FSGS, the collapsing type, is of particular interest because of its increasing incidence, specific histological features, frequent association with black race, HIV and I/V drug abuse and particularly its aggressive course.5 This lesion is however, increasingly being recognized in non-blacks with no evidence of HIV and drug abuse.55 Collapsing FSGS has not been reported from Pakistan till date. In this letter to the editor, we report our preliminary experience of this lesion. We reviewed our 12 year renal biopsies record and identified 10 cases of this entity. All the patients were young adults (average age 22.4 years with a range of 14-30 years). Majority were males (9 vs. 1 female). All presented with nephrotic syndrome (average 24 hours urinary protein was 6.7gm/d and a range of 2.5 to 33 grams). In addition, 8 had mild to moderate renal failure. No history of heroin or I/V drug abuse was elicited and all tested negative for HIV. Although, first described in AIDS patients, this lesion is increasingly being reported in patients who have no HIV infection or risk factors associated with this exposure. Most of these did not respond to standard treatment with steroids. Four of our patients developed end stage renal failure over a mean period of 1.5 years. Rapid progression to renal failure is a prominent feature of this subtype of FSGS. It is thus important for pathologists to be aware of this highly aggressive form of FSGS. Javed Iqbal Kazi, Muhammed Mubarak Histopathology Department, Sindh Institute of Urology and Transplantation (SIUT), Karachi.
1.Haas M, Spargo BH, Coventry S. Increasing incidence of focal segmental glomerulosclerosis among adult nephropathies: A 20-years renal biopsy study. Am J Kidney Dis 1995; 26: 740-50.
2.Haas M, Meehan SM, Karrison TG, Spargo BH. Changing etiologies of unexplained adult nephrotic syndrome: A comparison of renal biopsy findings from 1976-1979 and 1995-1997. Am J Kidney Dis 1997; 30: 621-31.
3.Kitiyakara C, Kopp JB, Eggers P. Trends in the epidemiology of focal segmental glomerulosclerosis. Sem Nephrol 2003; 23: 172-82.
4.Kazi JI, Mubarak M, Ahmed E, Akhter F, Naqvi SAA, Rizvi SAH. Spectrum of glomerulonephritides in adults with nephrotic syndrome in Pakistan. Clin Exp Nephrol 2009; 13: 38-43.
5.D'Agati VD, Fogo AB, Bruijn JA, Jennette JC. Pathologic classification of focal segmental glomerulosclerosis: A working proposal. Editorials. Am J Kidney Dis 2004; 43: 368-82.