Tuberculosis as primary renal diagnosis in end-stage uremia

Tuberculosis accounts for 0.5-1.0% of primary renal diagnoses among patients with end-stage renal disease reported to the EDTA Registry. In 1991, Greece was the country with the highest incidence (4.51%) among new patients taken on for dialysis/transplantation, followed by Portugal (2.03%). Some countries have reported not a single case of renal failure as a result of tuberculosis. We believe that the incidence of tuberculosis may have been seriously underestimated, since the tubulointerstitial form of tuberculosis, as opposed to the classical form, can easily be overlooked. There could also be patients classified under other EDTA diagnostic codes. Furthermore, in the EDTA database certain categories of renal diagnosis (00, 10, 20, 30) covering almost 40% of the whole renal population, have deliberately broad usage. Therefore, it is possible that some of the individuals allocated to these groups could have tuberculosis as primary renal diagnosis. We have no direct evidence to support this claim but our study of patients with end-stage renal disease suggests that patients with presumed glomerulonephritis behave differently from the well defined group of patients with biopsy proven glomerulonephritis, as regards evolution of renal bone disease. As a treatable form of progressive renal failure it is clearly important to identify individual cases. Therefore, renal biopsy should always be considered in patients with equal smooth kidneys radiologically, whose renal diagnosis is unknown and who come from an 'at risk' population as variation in the incidence of tuberculosis between racial groups is well established.