Occurrence of kidney diseases and patterns of glomerular disease based on a 10-year kidney biopsy material: A retrospective single-centre analysis in Estonia

Abstract

Objective. Kidney biopsy is an important diagnostic tool in assessing glomerular damage. This study aimed to determine the occurrence of glomerular disease during the past decade at a single centre, to assess potential changes in the structure of primary glomerulopathies over time, and to define gender- and age-related differences. Material and methods. A total of 578 consecutive native kidney biopsies during the period 2000–2010 was retrospectively reviewed at Tartu University Hospital, Estonia. Biopsies were evaluated according to clinical data with standard histological methods. Results. The patients' mean age was 39.9 ± 17.9 (range 4–87) years. Less than half of informative kidney biopsies (n = 547) comprised primary glomerulopathies (45.4%), the patients' mean age was 38.7 ± 17.7 (4–79) years and the predominant group comprised male patients. Secondary glomerulopathies made up 22.3%, tubulointerstitial diseases 8.2% and other conditions 24.1%. Among primary glomerulopathies, inflammatory damage to glomeruli dominated (63.4%), whereas immunoglobulin A (IgA) nephropathy was the most common disease (35.5%). Non-inflammatory diseases of glomeruli made up 34.6%, among which the most common was focal and segmental glomerulosclerosis (16.1%), followed by minimal change disease (14.1%). Membranoproliferative glomerulonephritis was a rare form of glomerular damage among primary glomerulopathies (7.7%). Comparison between male and female cases in the primary glomerulopathies group revealed a statistically significant difference in their frequency (p = 0.01). Conclusions. Inflammatory glomerulopathies mostly prevailed in the spectrum of primary glomerulopathies. IgA nephropathy was the most common glomerulopathy. Comparing the data with those from a 15-year earlier period at the same centre, a change towards non-inflammatory glomerulopathies was noticed.

Key Words::

• chronic glomerulonephritis
• epidemiology
• glomerular diseases
• IgA nephropathy
• kidney biopsy

Acknowledgements

The authors thank Mr Gordon Leman for the English correction, and their colleagues for their kind collaboration in clarifying the data.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.