Therapy of Glomerulonephritis: Survey Results and Comment

The questionnaire on clinical policies on diagnosis and treatment of glomerulonephritides was answered by 863 readers of NDTe. Fifty one percent of the answers were from EU countries (west 38%, east 13%), the other half was mainly from Asia (23%) and South America (12%). Seven percent of the answers came from North America, while 4% and 3% were sent from Africa and Oceania, respectively (fig. 1). This distribution is similar to the national distribution of our readership.

Figure 1

Most likely the vast majority of the responses were entered by nephrologists because over 99% stated that they perform renal biopsies in their units. This is in accordance with another ERA-EDTA poll (www.era-edta.org/POLLS.htm). Two-thirds of the units performs less than 50 renal biopsies per year (fig. 2).

Figure 2

Among the responders, the 15% perform more than 50 renal biopsies per year (fig. 3). Thus in the majority of nephrology units renal physicians share the care of a limited number of glomerulonephritis patients.

Figure 3

The biopsy report is generally made by a renal pathologist (81%, fig. 4). However, only one-third of the centers co-operating with a renal pathologist are having regular clinico-pathological conferences (29%).

Figure 4

The therapy is based on personal experience and literature review in the majority of cases (fig. 5) and nearly a half of nephrologists monitor the effects of therapy (fig. 6).

Figure 5

Figure 6

The number of published guidelines on therapy of glomerular diseases is limited. This is perhaps reason why more than half of the responders are in favor of a European-wide glomerulonephritis network to support diagnostic and therapeutic strategies (fig. 7).

Figure 7

Comment: Glomerulonephritis accounts for approximately 8 – 30% of end-stage renal disease (www.usrds.org, www.anzdata.org.au) 1-3. On 15th January 2009 we could retrieve 1183 articles by searching PubMed (www.ncbi.nlm.nih.gov) with the term “glomerulonephritis” limited to Clinical Trial, Meta-Analysis, Practice Guideline or Randomized Controlled Trial. For comparison, the term “dialysis” searched with the same limits produced 7071 articles, “diabetes” 20,744 and “hypertension” 24,712 articles. Thus, “Clinical Glomerulology” (i.e. GNs diagnosis and therapy) appears  to be a less attractive field    than  hypertension or  diabetes, an observation  indicating that the interest of nephrologists  for the various clinical research areas  in our specialty  is  broadly proportional to the epidemiological relevance of  the same areas .
During the past 20 years, a major effort has been made by several groups to describe the natural history and to test possible therapeutic interventions for  glomerulonephritides. However, all Cochrane Systematic Reviews (www.cochrane-renal.org) 4-7 about the specific treatment of glomerulopathies came to the same conclusion: There is not enough evidence!  How can this be?
Several reasons can be identified:

1. Diagnosis: The indication for renal biopsy is variable from country to country due to technique and health care policies.
2. Clinical trials: Although there are an increasing number of clinical trials in nephrology, most trials for glomerulonephritis are limited by the small number of included patients. Another limitation is the heterogeneity between the studies testing similar hypotheses. Finally, the long follow-up in most glomerulonephritides results in a high drop-out rate of participants. Furthermore, some studies might have been closed due to relocation or loss of interest or even retirement of the primary investigator.
3. Industrial sponsorship is difficult to obtain.

Despite all these limitations the day-to-day caring nephrologist does have a natural interest in diagnosing and treating glomerulonephritides because it is a disease which is not cared for by other medical subspecialties.
Recently, Francesco Paolo Schena has made a submission  to the European Commission to increase harmonization of the research units within Europe involved in the glomerulonephritis field 8. Although his initiative mainly focuses towards co-operation with the new Eastern European countries, it could be a start to a European-wide initiative to collect data on diagnosis and therapy of glomerular diseases. Free and regular dissemination of well selected   information is fundamental to improve our daily practice. Building up a glomerulonephritis network in which every nephrologist can share data on his or her patients with the community is a worthy enterprise for the European  renal community.