Old article, but nice review:
NEJM 2006;354:1927-1935
Key Points:
-90% mortality of TTP if untreated
-Pentad not needed for dxn, only MAHA and low plts along with appropriate clinical setting
-Childhood HUS with diarrheal prodrome (Shiga toxin/E.Coli O157:H7) treatment is only supportive care and antiobiotics should be withheld intially unless toxic/bacteremic since it may release more Shiga toxin and exacerbate the HUS
-ADAMTS13 deficiency (cleaving ulVWF) NOT seen in diarrheal prodrome HUS
-Neuro symtpoms more with TTP, renal more with HUS
-Distinguish TMA due to other disorders incl malignant HTN and autoimmune disorders
-LDH levels will be sky high often, schistos, polychromatophilic red cells, indirect bili, neg direct Coombs
-Acute flares may or may not have low levels of ADAMTS13, so cannot go by this, it only tells you risk of relapse
-PEX!!!! If delay, can use plasma infusion but not as effective. Steroids maybe
-Causes: Idiopathic (rare to have renal manifestations), pregnancy, autoimmune d/o, diarrheal prodrome (HUS), immune mediated and dose dependant drug toxicity, HST (TMA usually limited to kidney, unlikely to benefit from PEX)
-PEX works even if no severe ADAMTS13 deficiency
Nice review Ojas. I call these diseases more of a TMA rather than HUS/TTP. I think that HUS and TTP are two extremes of a TMA process. And if we rely on those diagnosis, we can miss subtle TMAs.
ReplyDeleteAnd in terms of TPE response, I think that an ADAMTS13 inhibitor related TMA is the only one that will respond to TPE and perhaps a TMA related to an anther autoantibody like in SLE. Rest of which are non antibody mediated, will less likely respond to TPE.
http://pascalelane.wordpress.com/2010/07/08/tis-the-season-for-hemolytic-uremic-syndrome/
ReplyDeleteCheck out the latest blog from Dr.Lane about HUS as well.