The Deadly Dinner Party: and Other Medical Detective Stories Read online

  Bottone theorized that Limone might have picked up the PA at work in the hospital lab. But he excluded this as a likely possibility for two reasons. For one, Limone worked in an administrative area, not a clinical one. Also, Bottone collected and cultured the loofahs of ten different microbiology technicians and found that none of them were positive for PA.

  His other theory was that trace amounts of PA in her home’s running water contaminated Limone’s sponge and then grew freely when the sponge was kept wet. Small amounts of PA are occasionally found in water supplies, even in tap water. The number of organisms is small, however, and not harmful (even if we drink the water, the tiny portion of bacteria is killed by our stomach acid before it can hurt us). But it can lead to problems if it’s allowed to grow.

  Limone took two showers daily, and her husband (who didn’t use the sponge) took one every day. Limone kept the loofah, which measured four by eight inches, hanging on the hot water knob in the shower. Because of the sponge’s size, where she kept it, and the number of showers it was exposed to each day, it never dried out enough for the bacteria to die. When she showered with the contaminated loofah, she was essentially rubbing the bacteria all over her skin, inoculating herself through tiny cuts from shaving her legs or perhaps even through minor skin abrasions caused by the loofah itself.

  Bottone tested individual pieces of loofah. He found that when he placed very small quantities of PA onto a loofah and let it sit overnight, the number of organisms the next morning had multiplied over a thousandfold. Other experiments showed that loofahs incubated with tap water or even distilled water would also start growing PA.

  Doctors say that any sponge—or even a washcloth—that remains wet all the time is prone to harbor bacteria. People typically launder their washcloths periodically, which removes the bacteria, but they usually don’t put their sponges in the washing machine. So sponges are far more likely to be the culprit. Sponges made from natural materials (such as loofah or sea sponges) are most susceptible to contamination.

  After solving Josephine Limone’s medical mystery, Edward Bottone went in search of ways to make natural sponges safer to use. He found that soaking a sponge in a 10 percent solution of household bleach (one part bleach to nine parts water) for about five minutes, then thoroughly rinsing, was very effective against bacteria. The sponges should be soaked at least once a week.

  One microbiologist, Dr. George Tortora from the State University of New York at Stony Brook, experimented with using a microwave oven to sterilize sponges and loofahs. He found that microwaving them for two minutes on the high setting would kill nearly all the bugs, and five minutes would completely sterilize the sponges. He cautions that the sponge must be wet when microwaved, because the high temperature of the resultant steam is what sterilizes it.

  Shortly after Bottone’s case report appeared in the medical literature, another instance appeared, but this one was related to a synthetic sponge made of nonwoven polyester. The case was almost a carbon copy of Limone’s: a healthy thirty-two-year-old woman developed forty to fifty papules on all parts of her body over a four-day period. A culture of one of the skin lesions was positive for PA. She had no exposures to hot tubs or swimming pools. Her doctor cultured her sponge and found the same organism.

  Another case report described an almost identical situation, but this time the offending vector for the PA was a Caribbean sea sponge that a forty-four-year-old woman was using in the shower.

  Shortly thereafter, Italian physicians reported on fourteen patients who had acquired PA folliculitis from their home showers. All had typical patterns of pustular rashes that grew out PA on culture. In five families, two or more members had the disease at the same time. The investigators found that the sources of the PA included well water, the filter from a washing machine, a bidet, and the bathroom sink faucet.

  In another strange but related outbreak, in April 2002, a cardboard box manufacturing plant in Arkansas hired an environmental health consultant to look into a cluster of employees who had been plagued by unusual skin rashes. It turned out that the facility had recently switched to a closed system for the water used in its industrial process, wherein the used water is recycled and treated and then reused by the boxmaking machinery. Twenty-seven employees had pustular rashes on their arms, legs, and torsos. The recycled water grew out PA.

  The closed recycling system was abandoned, and the pipes were thoroughly cleaned. The employees were educated about the source of the rashes, and hand-washing stations were created. Glove use was also encouraged. Follow-up surveillance showed no more PA in the water, and the employees remained healthy.

  Two different groups of physicians, one from southern France and the other in Pennsylvania, described a total of four other unusual cases of PA skin infection that was related to wetsuit use by scuba divers. All of these case reports and clusters of cases show just how ubiquitous PA is. After all, water is everywhere.

  Once Bottone had figured out the cause of Limone’s strange malady, curing it was simple. She took an antibiotic, and within a couple of weeks she was fully recovered. Even the pimples disappeared completely. Still, the experience changed at least one aspect of Limone’s life: she’s sworn off loofah sponges forever. “I never use them anymore at all,” she says. “In fact, I’m even cautious about using a washcloth.

  “A lot of my friends buy at the Body Shop, and they make these gift baskets with bath oil beads and the loofah sponges. I always tell everyone the story. I think people can relate to it because they all use them too.”

  5 The Forbidden Fruit

  It began as innocently as a thousand other cases. It could have happened anywhere, and it might have involved any family. So on the evening of Sunday, November 10, 1991, Peter and Michele Burdick were not particularly alarmed when their only child, Emily—a petite blonde, not quite four years old at the time—began having abdominal cramps and diarrhea. Such symptoms are a normal part of growing up, and nearly every child at some point will have them. When Michele began to feel some cramps too, she figured that it was just something that they had both eaten.

  “The next morning, Emily woke me up early, complaining of a stomach ache. I told her to lie down and that it would probably go away,” recalls Michele, who is from Somerset, Massachusetts, “but by afternoon, it hadn’t gone away; in fact, she was worse. That evening I noticed some blood in her stools.” Monday was Veteran’s Day, and the pediatrician’s office closed early. Figuring that Emily would probably get better on her own, Michele waited until Tuesday to bring her daughter to the doctor. Dr. Margaret Bello, covering for Emily’s regular pediatrician (Dr. Walter Rok), examined her and then arranged for blood tests and x-rays to be performed at St. Anne’s Hospital in Fall River.

  “This was Emily’s first experience going through these kinds of tests. She was complaining that her tummy hurt and that she wanted to be carried,” her mother recalled. After the tests were completed, the Burdicks returned home and arranged a follow-up visit for the next day. There was an implicit expectation that, as in most cases of diarrhea, mother’s and daughter’s symptoms would both start to resolve on their own.

  But instead of turning the corner and improving, the situation deteriorated; Michele and Emily kept getting sicker.

  “By late Tuesday, I developed cramps that seemed to worsen by the hour. Emily’s trips to the bathroom were becoming more frequent. She was crying a lot and asking me to sit with her in the bathroom to rest her head on my lap. And my husband, Peter, was working the night shift from 6:30 PM to 6:30 AM, so I was all alone with Emily. Then I developed diarrhea and the cramps got much worse. It got to the point where I could barely assist Emily, my pains were so severe.”

  Peter called to check on his wife and daughter from his job on an assembly line at a nearly manufacturing mill. The report he received was not good. Emily and Michele spent the night on the couch because it was closer to the bathroom. But neither of them slept. As dawn approached, the situation turned far m
ore ominous. Each bowel movement Michele had was progressively bloodier. Enough of toughing it out at home; they called the doctor back.

  Dehydrated and now losing blood, both mother and daughter were promptly admitted to St. Anne’s Hospital on Wednesday morning. Michele required intravenous fluids and pain killers. She was exhausted.

  So was Peter. “I had been up all night at work,” he remembers, “and felt stressed and anxious because Michele and Emily were so sick. It all happened so fast. On top of everything, we had previously scheduled a repair man to install a new stove that morning.” He stayed with Emily in her hospital room all that day and night until his parents were able to come from Cape Cod to relieve him so he could get a few hours sleep. Thursday brought more of the same.

  Emily and Michele Burdick were both suffering from gastroenteritis, the medical term for inflammation of the intestines. The most common symptoms are abdominal cramps, nausea, vomiting, and diarrhea. Even without blood, the volume of diarrhea can be so great that patients become seriously dehydrated. Worldwide, gastroenteritis is one of the most common diseases in humans. Infectious agents, mostly viruses and bacteria, are the usual culprits, but various toxins that these organisms produce, as well as some parasites and toxins from other sources, also cause gastroenteritis. Most cases are self-limited; even most cases of the bacterial variety resolve after a few days. The treatment is merely to replenish the body orally with fluids to prevent dehydration, and maybe take some acetaminophen or ibuprofen for the aches, pains, and fevers.

  In spite of the simple treatment, gastroenteritis and dehydration are huge problems in the developing world. Childhood diarrhea is a common cause of mortality in the third world, where it accounts for 70 percent of all hospital admissions due to infectious diseases, as well as half of all childhood deaths in both India and Afghanistan. Cholera is one cause of gastroenteritis that, in the days before intensive rehydration therapies, had a very high death rate. But even viral gastroenteritis can kill an infant or small toddler pretty quickly, because they don’t have large reserves of fluid in their little bodies. The loss of relatively small amounts of fluid leads to dehydration, which in severe cases can lead to death.

  Replacing the fluids to prevent this outcome has traditionally needed to be done intravenously, but in recent decades doctors are increasingly using newly developed oral rehydration techniques, which are both very inexpensive and very effective, to reduce infant mortality in the third world.

  When the diarrhea turns bloody, it generally means that the causative organism is bacterial or that there is some form of inflammatory condition of the colon, such as ulcerative colitis. In the first case, it suggests that the responsible organism is actually invading the wall of the intestine. Whatever the cause, the development of blood in the diarrhea is not a good thing, and can understandably frighten a patient, especially a child. Patients with bloody diarrhea sometimes lose enough blood to require a transfusion. But there are other, more sinister problems that may occur that have nothing to do with blood loss.

  In Emily’s case, soon after she was admitted to the hospital Dr. Rok took over her care. “The blood loss was substantial, and the initial stool cultures ruled out salmonella, shigella, and campylobacter—the more common causes of bloody diarrhea,” he explained. On Friday, Dr. Rok received some alarming news from the lab: Emily’s kidneys were shutting down.

  The kidneys are two bean-shaped organs that lie deep in the abdomen. The heart pumps roughly 25 percent of the body’s blood flow through the kidneys, which filter the blood to remove waste products. These wastes are then carried from the body through excretion in the urine.

  Among the various substances the kidneys remove are two called urea nitrogen and creatinine. The level of urea nitrogen in the blood is abbreviated in medical lexicon as BUN (blood urea nitrogen). Measuring these two blood levels—the BUN and creatinine—is something that doctors across the country perform routinely millions of times each year to monitor their patients’ kidney function. The normal level for BUN is less than 20 milligrams per deciliter, and for creatinine, less than about 1.2. When the BUN and creatinine levels rise above these values, the condition is known as renal insufficiency or kidney failure. There are different degrees of renal failure, and many different causes. So when they are faced with this situation, doctors go through a checklist to determine the reason. There are three general reasons for kidney failure. The first is called “pre-renal,” meaning there is a problem in the system before blood reaches the kidneys. This usually means that not enough blood is getting to the kidneys, sometimes from very low blood pressure or severe dehydration. A certain amount of pressure is necessary for the kidneys to properly do their work, and if that blood pressure falls, the kidneys begin to fail and the levels of BUN and creatinine start to increase.

  In another type of kidney failure, termed post-renal, the cause is a blockage or obstruction in one of the tubes that carry the urine from the kidneys out of the body. This is essentially a plumbing problem, and when the blockage is relieved, the kidney function usually promptly normalizes, and the levels of BUN and creatinine return to normal. One of the most common causes is obstruction of the flow of urine due to an enlarged prostate gland. In both pre-renal and post-renal failure, the kidneys themselves are not the source of the problem.

  The third kind of renal failure is when the kidneys themselves do not function correctly; the problem is intrinsic to the kidneys themselves. The list of possible causes of this kind of renal failure is long and includes problems due to immunological attack, infection, side effects from various medications, and a host of others. An example of immunological attack is called glomerulonephritis. There are many causes of this condition, one of which is the after effects of strep throat. Over time, chronic medical conditions such as high blood pressure and diabetes can lead to intrinsic renal failure.

  The treatment of a patient with renal failure will depend entirely on the cause. If it is due to severe dehydration leading to pre-renal failure, intravenous fluids will often do the trick. In most cases of post-renal problems, the solution is mechanical. If there is trouble with the prostate, doctors will insert a small catheter into the bladder to relieve the obstruction of urine. Some cases of renal failure resulting from intrinsic kidney disease are treated with steroids; others require more powerful immune modulating drugs. But if these treatments do not work, intrinsic renal failure may require treatment with an “artificial kidney,” known as a dialysis machine.

  When Dr. Rok saw that Emily’s BUN was 35 and her creatinine was 2.6, he quickly sought to determine the specific cause. There were two clues that led Dr. Rok to consider the possibility of a most unusual disease. One hint was the appearance of Emily’s red blood cells under a microscope: the cells appeared shredded, ripped apart, or hemolyzed, in medical jargon. The second was the context in which the kidney failure was occurring: bloody diarrhea. Although he had seen only one case, years ago when he was in training, Dr. Rok was pretty sure that he was dealing with a case of hemolytic uremic syndrome, or HUS.

  First described in 1955, HUS is a rare disease. The medical term for kidney failure is uremia, and the condition that causes the shredded cells that Dr. Rok saw under the microscope is hemolysis—hence the term hemolytic uremic syndrome. Experts believe that the symptoms result from damage to the lining of small blood vessels in the kidney, which leads to the renal failure. Blood platelets, an essential component of normal blood clotting, drop to precariously low levels. The kidneys and blood cells are not the only organs that can be affected: sometimes the liver becomes involved. Occasionally patients develop neurological symptoms, such as seizures and coma. More ominously, in approximately 5 percent of patients with HUS, the outcome is fatal.

  For many years, the cause of HUS was unclear. Instances would occur sporadically in various locations. Some of these cases were associated with infections of different kinds, often intestinal infections, such as gastroenteritis.

  Most cases are ass
ociated with eating food that has been contaminated with Escherichia coli bacteria. E. coli is an extraordinarily common bug that is present in enormous quantities in the intestinal tracts of humans and other mammals. It was first described in 1885 by a German pediatrician and microbiologist named Theodor Escherich, for whom it is named—the colon bacillus of Escherich. In humans, these bacteria colonize an infant’s intestine within the first two days of life.

  There are hundreds of different kinds of E. coli; each of these variations is called a serotype, and they are distinguished by a particular protein signature. Microbiologists describe the various types of E. coli by categorizing the proteins on the bacteria. On the body of the bug, there are proteins designated as “O,” and on the flagella (the whiplike arms the bacterium uses for locomotion), there are “H” proteins, and so forth.

  In December 1981, an outbreak of bloody diarrhea occurred in Medford, Oregon, and one of its suburbs, White City. Medford is a mediumsized town located in the Rogue Valley, west of the Cascade Mountain range. The tests for the standard pathogens that cause bloody diarrhea were negative, and the Oregon public health officials could not come up with an answer. They requested assistance from the CDC in Atlanta, which promptly dispatched a team of investigators. The lead investigator was a young epidemiology intelligence officer, Lee W. Riley, who flew out to Oregon the next day. The investigators were able to culture an extremely rare form of E. coli from most of the affected patients. When the protein tests were done, the strain was given the rather unceremonious name of O157:H7. At that time, E. coli bacteria were not thought to cause diarrhea, and because it is so common in human feces, nobody initially thought it was significant.

  The following May, as the Oregon investigation was unfolding, another cluster of patients with bloody diarrhea was identified in Traverse City, Michigan. The same O157:H7 strain was identified. The common denominator in both outbreaks was eating hamburgers from McDonald’s fast food outlets. When the CDC searched its database of more than three thousand E. coli samples, there was only a single specimen that matched the strain from the Oregon and Michigan outbreaks. It was from a stool sample of a fifty-year-old female naval officer from Oakland, California, and it had been collected in 1975. When the Navy dug up her records, it was found that she had been sick with a case of bloody diarrhea.