Long-Term Ills Tied to Bad Food

Also, the number of HUS cases is small. Only about 5 to 10 percent of the 73,000 people each year who get sick from E. coli develop HUS.

The impact of HUS, however, is great. In the acute phase, microscopic blood clots may form in the kidney, leading to kidney failure, Neill said. Sometimes the kidney can be rescued with temporary dialysis. Less commonly, these blood clots form in organs such as the brain and cause stroke or seizure. There may be permanent damage to the kidney.

According to a long-term study of 157 HUS victims co-written by Pavia in 1994, more than half developed kidney problems seven or more years after the initial illness.

These people face a lifetime of medical treatment. "Anyone with HUS will be monitored for the rest of their lives. If the acute course was severe enough, the risk of long-term kidney complications, including end-stage renal disease and kidney transplant, is quite high. The future medical cost alone can then be in the millions," said William Marler, a Seattle lawyer who sues retailers and food companies on behalf of food poisoning victims.

That is the scenario Elizabeth Armstrong faces. Her two daughters got sick after eating bagged baby spinach in 2006. Her older daughter, Isabella, who was 4 at the time, survived with no apparent health problems. But her younger daughter, Ashley, who was 2 at the time, developed HUS. She has only 10 percent kidney function and will likely need more than one kidney transplant in her lifetime, including one before she is an adult. Also, when she becomes an adult, Ashley may face the same dilemma that Sarah Pierce did: deciding whether bearing a child is worth the risk.

There may be a way to prevent the worst HUS cases and their consequences. Doctors in Washington state have found that it is important to hydrate a patient if they even suspect an E. coli infection. Doing so helps reduce the extent of injury to the kidneys. More research needs to be done to identify other effective interventions, said Phillip Tarr, an HUS expert at Washington University School of Medicine in St. Louis.

"There is a lot we don't know yet," Tarr said.

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