The name atypical hemolytic uremic syndrome is being replaced. Complement mediated thrombotic microangiopathy is becoming a popular choice.
The first term is explicitly associated with kidney disease, the second term is not.
How many patients diagnosed with the first term are vocal in that community when they find that they have no kidney evident problems like the rest around them have. Some of whom very much have residual kidney problems ?
But they exist.
In Global Action’s study of the aHUS diagnosis process, 15% of those participating reported no symptoms of failing/failed kidney disease. The “U” in aHUS did not apply to them.
So cTMA is what the condition they have would be called along with the 85% where the “U” does apply and very much so for many. It is part of the reason for the name change, to suit the minority “non Us”
Renal or kidney limited TMA would be difficult to diagnose if there is no evident thrombocytopenia not mechanical anaemia too.
But as Global Action found these kidney limited TMA patient incidents are not infrequent.
A kidney biopsy would reveal a TMA and complement genetic testing ( including known at risk haplotypes) could reveal a predisposition.
Unlike a catastrophic episode of aHUS where kidney failure is plainly evident kidney limited TMA (KL-TMA, isn’t that how nomenclature abbreviations work these days? Maybe the “K” should be “k”) is insidious and slow with some evidence of episodes of haematuria and mild proteinuria, which could be anything.
A case study by the Keratishvili Group demonstrates how a hidden cTMA can be unveiled and how complement inhibition can prevent a long term creeping kidney failure.
How many of these patients are out there?
If Global Action’s findings are true then as many as 3500 aHUS patients globally would be without evidence of acute kidney injury in a catastrophic episode. But there may be a slow creeping kidney injury problem going on.
Here is a thought, are known predisposed relatives monitored for progressive kidney limited TMA ?
Article No 798
