The renal histopathological spectrum of patients with nephrotic syndrome: an analysis of 1523 patients in a single Chinese centre

The renal histopathological spectrum of patients with nephrotic syndrome: an analysis of 1523 patients in a single Chinese centre Sir, I have read with interest the article by Zhou et al. [1] published in your journal. Although, inherently biased, these biopsy studies are important in understanding the pattern of renal diseases in a particular area. The renal diseases are notorious for regional, racial, gender and age-related heterogeneity [2]. We have also reported the histopathological profile in adults with idiopathic nephrotic syndrome (INS) from Pakistan [3]. Our findings are in marked contrast to those of Zhou et al. [1]. The latter have analyzed both primary and secondary glomerulonephriti-des, in contrast to our analysis, which was restricted to INS. Of particular interest is the low prevalence of focal segmental glomerulosclerosis (FSGS) in the subject study. In our nephrotic adults, FSGS is the dominant pathology, which is also the case in most recent studies from around the world [4]. The authors have found hypoalbuminemia as a useful parameter in further refinement of diagnosis. This is an interesting finding worth further investigation in larger, prospective studies and may lead to a change in biopsy policies. There are, however, a few discrepancies in the article as described below: The use of the term 'nephrotic' for 397 patients with non-nephrotic proteinuria is unwarranted. The authors selected only cases presenting with nephrotic syndrome (NS) or nephrotic-range proteinuria, but in the methods, they enlist all six indications for renal biopsy. We are also curious as to the rationale behind the particular age group cutoffs used in the study. The numbers of amyloidosis in the footnote of Table 1 are not correct. The authors state that 59 diabetic patients received renal biopsy, and among these, 50 were diagnosed with non-diabetic nephropathy, which means, nine patients suffered from diabetic nephropathy (DN). But, the number of cases of DN given in Table 1 is 11 þ 3 ¼ 14. The cohort of non-IgA mesangial proliferative glomerulonephritis is interesting and quite large. One wonders, why some of these cases do not qualify for IgA nephropathy or IgM nephrop-athy, given the 2þ and 3þ positivity of respective antibodies on immunoflourescence. IgG positivity in these cases also needs explanation. The prevalence of hepatitis B surface antigen positivity is lower in their nephrotic patients than in the general population. In contrast, the proportion of hepatitis B virus-associated glomerulonephritis (HBVGN) is higher than that observed from …