Glomerular diseases in children. "The Iranian experience"

Pediatric Glomerular Diseases in North India-Epidemiology and Clinicopathologic Correlation

Background

Glomerular diseases vary with age, and it is important to investigate the spectrum of glomerular diseases in pediatric patients to help in a more precise clinical diagnosis and optimize the management of patients. We aimed to study the clinicopathologic pattern of pediatric glomerular diseases in North India.

Methods

This is a 5-year retrospective, single-center cohort study. The database was searched to identify all pediatric patients with glomerular diseases in their native kidney biopsies.

Results

About 2890 native renal biopsies were studied, of which 409 were pediatric glomerular diseases. The median age was 15 years with a male preponderance. Nephrotic syndrome was the most common presentation (60.8%), followed by non-nephrotic proteinuria with hematuria (18.5%), rapidly proliferative glomerulonephritis (7%), isolated hematuria (5.3%), acute nephritic syndrome (3.4%), non-nephrotic proteinuria (1.9%), and advanced renal failure (0.7%). Minimal change disease (MCD) was the most common histological diagnosis, followed by focal segmental glomerulosclerosis (17.4%), IgA nephropathy (IgAN; 10%), membranous nephropathy (6.6%), lupus nephritis (5.9%), crescentic glomerulonephritis (2.9%), and C3 glomerulopathy (2.9%). Diffuse proliferative glomerulonephritis (DPGN) was the most common histological diagnosis in patients with hematuria and non-nephrotic as well as nephrotic range proteinuria. The most common histological diagnoses for isolated hematuria and acute nephritic syndrome were IgAN and postinfectious glomerulonephritis (PIGN), respectively.

Conclusions

MCD and lupus nephritis are the most common pediatric primary and secondary histopathologic diagnoses, respectively. The adolescent-onset glomerular diseases have a higher frequency of IgAN, membranous nephropathy, and DPGN. PIGN is still an important differential in our pediatric patients presenting with acute nephritic syndrome.

Renal biopsy findings in Iran: case series report from a referral kidney center

BACKGROUND

Several registries and single centers have reported the results of their renal biopsies from different parts of the world. As there are only few data regarding the epidemiology of glomerulonephritides in Iran, this study was conducted to determine the results of renal biopsy findings during the last 10 years in our center.

METHODS

Data from 1,436 patients who had undergone a renal biopsy in our center between 1998 and 2007 were collected retrospectively for the first 989 patients and prospectively for the rest of them, including demographic data, renal syndrome at presentation and laboratory findings. All kidney specimens were studied with light and immunofluorescent microscopies.

RESULTS

Among 1,407 patients with a definite pathologic diagnosis, 1,052 (74.8%) had a primary glomerular disease, 241 (17.2%) had a secondary glomerular disease, 66 (4.6%) had tubular disease, 19 (1.3%) had vascular disease and 7 (0.5%) had end-stage kidney disease. The most frequent types of biopsy-proven renal diseases were membranous glomerulopathy (MG) (377 patients, 26.8%), IgA nephropathy (IgAN) (155 patients, 11%), lupus nephritis (155 patients, 11%), focal segmental glomerulosclerosis (141 patients, 10%) and minimal change disease (117 patients, 8.3%). The predominant presentation was nephrotic syndrome in almost all cases, with the exception of chronic glomerulonephritis, acute tubular necrosis and acute tubulointerstitial nephritis. The epidemiology of our renal biopsy findings was similar to reports from most European countries and United Arab Emirates, but different from many other neighboring countries, North America and Far East.

CONCLUSIONS

In our report of 1,407 renal biopsy specimens, MG and IgAN were the most frequent biopsy-proven renal diseases. FSGS was the third cause of primary glomerular disease, and lupus nephritis was the most common secondary glomerular disease. The unusually high frequency of presentation as nephrotic syndrome may be due to referral nature of our center and less liberal indications for renal biopsy.

Histopathological spectrum of childhood nephrotic syndrome in Pakistan

BACKGROUND

There is no information in international literature on the pattern of glomerulopathies in children with idiopathic nephrotic syndrome (INS) in Pakistan. We undertook this study to determine the pattern of glomerulopathies based on renal biopsies studied by light (LM), immunofluorescence (IF), and electron microscopy (EM).

METHODS

The study was conducted at Sindh Institute of Urology and Transplantation (SIUT), Karachi over 12 years (1996-2008). All children (<or=18 years) with INS in whom renal biopsy was performed were included. Renal biopsies were studied by LM, IF, and EM.

RESULTS

Of 538 children, 347 (64.4%) were male and 191 (35.5%) were female. Mean age was 9.79 +/- 4.59 years. The histopathological lesions comprised: minimal change disease (MCD) and its variants, 43.8%; focal segmental glomerulosclerosis (FSGS), 38.14%; membranous glomerulonephritis (GN) (MGN), 7.96%; mesangioproliferative GN (MesPGN), 4.81%; mesangiocapillary GN (MPGN), 3.14%; IgA nephropathy (IgAN), 1.11%; and other rare lesions.

CONCLUSION

MCD and its variants are the leading cause of overall INS in children, followed by FSGS, which is the predominant pathology in steroid-resistant and adolescent nephrotic syndrome (NS). Our data are in accordance with recent series from around the world with similar biopsy indications. The study defines the true pattern of glomerulopathies in childhood INS for the first time in Pakistan.

Outcome of severe acute post-streptococcal glomerulonephritis in New Zealand children

Post-streptococcal glomerulonephritis (PSGN) is the commonest cause of severe acute glomerulonephritis in New Zealand children, with the majority (85%) of the patients being of either Pacific Island or Maori ethnicity. We have performed a retrospective study on 27 pediatric patients with acute PSGN. Of these patients, those with crescentic glomerulonephritis (n = 11) had a greater tendency (72.7%) for needing acute dialysis and were left with persistent urinary sediment abnormalities after a mean follow-up of 3.2 years (95% confidence interval 2.1-4.3). The efficacy of immunosuppression in the group with crescentic disease was uncertain. The severity of renal histopathological abnormalities as judged by the total biopsy score did not correlate with either presentation or eventual outcome. Severe childhood acute post-streptococcal glomerulonephritis, although uncommon, results in significant long-term renal morbidity, particularly among Maori and Pacific Island children.

Childhood renal diseases in Saudi Arabia. A clinicopathological study of 167 cases

Between April 1982 and September 1994, 167 renal biopsies were performed in 167 children at King Khalid University Hospital, Riyadh, Saudi Arabia. The data were analysed to show a correlation between clinical presentation and histological findings. Nephrotic syndrome was the most common indication for renal biopsy, accounting for 77% of all cases. Of these, 23.3% showed minimal change lesions, 24% showed mesangial proliferative glomerulonephritis and 24% showed focal segmental glomerulosclerosis. We noted a higher incidence of congenital nephrotic syndrome and Alport's syndrome as compared with the West. On the other hand, IgA nephropathy was less common (3%), and there was a complete absence of type II membranoproliferative glomerulonephritis.

Spectrum of renal pathology in 100 selected children with nephrotic syndrome

The study includes 100 renal biopsies from an equal number of patients referred to us with nephrotic syndrome (NS). Their ages ranged from one month to 13 years (medial five years) and included 59 males and 41 females. Indications for kidney biopsy were steroid resistance in 41 patients, steroid dependence with frequent relapses on maintenance steroid therapy in 38, NS associated with gross hematuria, hypertension, azotemia, and/or systemic manifestations in eight and age of less than one year at the onset of the disease in 13 patients. In 90 patients, NS was idiopathic in origin and in eight, it was secondary to IgA nephropathy, hemolytic-uremic syndrome, post streptococcal glomerulonephritis, antiglomerular basement membrane antibodies, Henoch-Schonlein nephritis and systemic lupus erythematosus. Two patients had hepatitis B infection and its relationship with NS could not be elucidated. Primary NS is the predominan type of NS in the local pediatric population. The disease in more common in the first year of life. A relatively high incidence of diffuse mesangioproliferative glomerulonephritis (MesPGN) and rarity of infection-related NS are noted.

Clinicopathological features of childhood nephrotic syndrome in Saudi Arabia

The clinicopathological features are described in 119 Arab children in Saudi Arabia with the nephrotic syndrome. The clinical and laboratory data are similar to those described in other parts of the world. However, mesangial proliferative glomerulonephritis (MesPGN) was found in 21 of 66 biopsies (31.8%), giving a frequency of 17.6% of all children with the nephrotic syndrome. Minimal-change nephrotic syndrome (MCNS) was diagnosed in 17 biopsies (25.8%) and in 58 patients (48.7%). Onset of the nephrotic syndrome was at less than 1 year of age in 17 patients (14.3%). Seven children had 11 episodes of peritonitis. Seven children had positive hepatitis B surface antigen (HBsAg) in their serum: renal biopsy carried out on four of them showed membranous glomerulonephritis (MGN) in three, and four of the seven patients developed end-stage renal disease (ESRD). There were nine deaths, all in patients with end-stage renal disease: six of the deaths occurred in infants. The pattern of childhood nephrotic syndrome in Saudi Arabia is different from the pattern in tropical countries.