One additional piece of evidence against the "hypetensive nephrosclerosis" hypothesis is the existence of a rare, autosomal recessive disorder termed "Hypertension/Brachydactyly Syndrome", the gene for which has yet to be identified. These individuals suffer brachydactyly a relative shortening of the fingers and toes, see picture) and severe hypertension, with systolic blood pressures often well greater than 200. The mechanism of their hypertension is not entirely clear, but what is interesting in this small cohort of patients is that even after decades of exposure to blood pressures in the "malignant" range, very few develop renal damage. They do have stroke commonly, but not renal disease.
Monday, September 29, 2008
One of the as-yet unresolved major controversies in nephrology is whether or not the entity "hypertensive nephropathy" really exists. Certainly there are a large percentage of the dialysis population who do not have diabetic nephropathy, glomerulonephritis, nephrotic syndrome, obstruction, or other obvious explanations for their renal failure other than the risk factor of hypertension. Hence, the term "hypertensive nephrosclerosis" which we use frequently. However, there is now a HUGE percentage (in fact, a majority) of the adult population in the U.S. and the vast majority of these folks do not ever get kidney disease, suggesting that hypertension alone is not sufficient to cause renal damage.