It appears that the E. coli O104 sproutbreak is starting to wind down, with more than 3,500 cases diagnosed to date and 39 deaths. Though sprouts remain the key source of the bacterium, a recent report also documents that human carriers helped to spread the organism (via H5N1 blog). In this case, it was a food service employee working at a catering company, who spread infection to at least 20 people before she even realized she was infected.

As with many infectious diseases, there are potential lingering sequelae of infection, which can occur weeks to years after the acute infection has cleared up. Like almost 800 others involved in this outbreak, the woman who unwittingly infected others via food developed hemolytic uremic syndrome, or HUS. We now know that the most common cause of HUS are bacteria such as STEC (“shiga toxin-producing E. coli“); the “shiga toxin” that they produce inhibits protein synthesis in the host and cause cell death. This can have systemic effects, and leads to clotting in affected organs–most commonly the kidneys, but other organs can also be affected. Dialysis may be necessary, and the infection can lead to kidney failure and the need for organ transplantation. There is already concern that, because of the huge numbers of HUS cases, many patients will have long-term kidney damage, including the potential need for additional organs (and possibly, re-vamping the way donations are made as well):

In previous E. coli outbreaks, up to half of patients who developed the kidney complication were still suffering from long-term side effects 10 to 20 years after first falling sick, including high blood pressure caused by dialysis.

In addition to possible kidney problems, people who have survived serious E. coli infections may also suffer from neurological damage, as the bacteria may have eaten away at blood vessels in the brain. That could mean suffering from seizures or epilepsy years after patients recover from their initial illness.

While it’s common knowledge in the medical community now that STEC can lead to HUS, which can lead to chronic kidney issues, for many years, the link between E. coli and HUS was obscured. HUS first appears in the literature in 1955, but the link to STEC wasn’t confirmed until the early 1980′s. In the interim, myriad viruses and bacteria were examined, as well as genetic causes. (There are cases of HUS caused by host mutations and other etiologies, but they are much less common than HUS caused by STEC and related organisms). In future posts this week, I’ll delve into the history of HUS and look at a few studies which examined alternative hypotheses of causation, until finally STEC was confirmed as the causative agent. I’ll also discuss what this means as far as discovering infectious causes of other “complex” and somewhat mysterious diseases whose causes are unknown, as HUS was a mere 30 years ago.

Comments

  1. #1 CM Doran
    June 20, 2011

    Thank you for writing about this….will you go into more depth about the carriage of this organism?

  2. #2 texascarrs
    June 20, 2011

    My 10 year old daughter has been in the hospita for the last 21 days with HUS secondary to E-Coli. But, as well as having this she has also had C-Diff and Giuardia. I am having a hard time figuring out where it all came from! The health department is involved, but I really haven’t gotten any answers. Have you dealt with all of these at the same time before?
    Thank you.

  3. #3 Bill Marler
    June 20, 2011

    Nicely done piece on HUS. Over the last 20 years we have developed an extensive site on HUS – http://www.about-hus.com/ – there is an extensive list of publications as well.

    As for the HUS case, keep on top of the health department. They do their best, but are usually underfunded and understaffed. Make sure you give them the most accurate information you can on where your daughter was and what she ate or drank the 3-4 days before she became ill. Is there anyone else ill. Linking an illness to a specific source is always difficult.

  4. #4 texascarrs
    June 21, 2011

    I have met with them extensively and I just happen to be a very anal person who writes EVERYTHING down on my personal calendar. I was able to give them 2 1/2 weeks of history of where she had been, eaten, etc… I really don’t mean to sound so disgruntled, but it concerns me that more time is passing and nothing has produced. To my knowledge, she is the only one in our area who came down with all of the above. Thanks for the encouragement, I will definitely stay on them. Like I said, it is frustrating when I am reading how they are tracking it down to something as small as bean sprouts and “to my knowledge” we do not even have a clue about or case.

    Thanks again!

  5. #5 Heidi Durrett
    January 25, 2012

    Hello, I see this is an older piece, but am looking for answers. My 12 yr old daughter is one yr post HUS. We have been ruled medically normal with only slightly lowered blood pressures, but nothing is normal. She has constant nausea and gagging, dizziness, extreme fatigue, pain to touch, a myriad of wierd symptoms. Our Dr’s at children’s hosptial agree that she isn’t normal, but can’t tell us what is going on. We are beginning to feel desperate. We don’t know where else to ask questions. Do you have suggestions? We just don’t know where to look next.