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Renal Syndromes

Syndrome number one is branchio-otorenal syndrome, BOR syndrome. You get dysplasia; unilateral renal agenesis is the renal anomalies, and other findings are branchial fistulas and in particular, preauricular pits and hearing losses. Those are underlined because those are the associations that you want to make. If you see somebody with a little pit in front of their ear and hearing loss, look for renal problems. Potter’s syndrome: renal failure, oligohydramnios.

Prune-belly syndrome; the renal abnormalities, dilated urinary tract, dysplastic, aplastic, multicystic and hydronephrotic kidneys. Underline absence of abdominal musculature, cryptorchidism. That’s called the triad because there are three of them. Cryptorchidism, absence of abdominal musculature, renal abnormalities.

Alport’s syndrome has glomerular lesions, hematuria and decreased GFR. Underline anterior lenticonus, cataracts, sensorineural deafness. First, lets look at prune-belly syndrome. Here is the prune-belly. Lacks abdominal musculature. Testes are not palpable. Renal abnormalities. Prune-belly syndrome. By the way, what do you notice? Is this a boy or a girl? Boy. Prune-belly syndromes are almost always in boys. And we can talk at some point about why that is, but it’s almost always in boys.

Tuberous sclerosis; you’ve heard about tuberous sclerosis. The renal abnormalities, renal angiomyolipoma, cystic kidneys and renal cell carcinoma. An important clinical link and association. Other features, underline adenoma sebaceae, underline CNS tubers, retinal phacoma and of course some of the skin, the shagreen patches, the White Mountain ash spots. We’ll talk about Drash syndrome, which is diffuse mesangial sclerosis, nephrotic syndrome in end-stage renal disease.

Renal tubular acidosis. How do we recognize renal tubular acidosis? Number one, what I said before; first have a blood pH. You’ve got to have acidosis. I can’t tell you how often I have been consulted by some of you out there who will remain anonymous, in the audience, who say, "Low CO2, low bicarbonate, we obviously have an acidosis. Please evaluate the acidosis for us." And it turns out, of course, that it’s a compensation because the blood pH, when we got it, was 7.6.

Now there are different types. We nephrologists have an incredible amount of imagination and wit, so we of course call them type I and type II, with our great creativity. Type I is called distal RTA. It is caused by a problem in the distal tubule with the inability to decrease the urine pH to 5.5 during acidosis. Because the kidney can’t push out hydrogen ions out of the body. There is one of a number of molecular defects that cause the kidney to be unable to kick out hydrogen ions. You eat 3 milliequivalents per kilo of hydrogen ion per day in your phosphates and your sulfates and the things that you eat.

The types; it is associated with many many things, and I’ve listed a number of them here. Genetically transmitted disease, autoimmune diseases and disorders associated with nephrocalcinosis. If you hear nephrocalcinosis and acidosis, think type I RTA, and there are a couple of situations here. Drugs that have tubular toxicity; we talked about hypokalemia with cisplatin.

Type II RTA is different than type I RTA. It’s not that you can’t excrete hydrogen ions. It’s that the kidneys leak bicarbonate. There is a low threshold in the blood for spilling bicarbonate in the urine. Normally you and I start to spill about 22 … or kids, actually, start to spill 22-24. In type II RTA they start to spill at 15-16, so they begin to lose their bicarbonate.