Hemolytic Uremic Syndrome

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The Connecticut State Department of Public Health (DPH) today issued the following update on the E. coli outbreak linked to the Oak Leaf Farm in Lebanon, CT:

As of 1:00 p.m. today, DPH is investigating 15 confirmed cases of E. coli O157 infection.  The number of cases could increase in the near future as DPH is actively identifying individuals who were not initially reported.

So far, investigators have been able to link 14 of these cases to Oak Leaf Farm.  The patients range in age from 1-44 years old, with a median age of six.  In total, five patients have been hospitalized with three still in the hospital.  Two of the hospitalized patients have been diagnosed with Hemolytic Uremic Syndrome (HUS), as first reported last week.

Yesterday, the Centers for Disease Control and Prevention (CDC) dispatched a team to Connecticut to assist in the investigation of this outbreak.  Today, officials from DPH, the Connecticut Department of Agriculture, the Uncas Health District, and the CDC team are at the Oak Leaf Farm conducting an onsite investigation.  The Farm remains voluntarily closed to the public, and the owners are cooperating with the investigation.

The outbreak was first identified on Thursday, March 24th when six of seven individuals sickened with E. coli were confirmed by DPH to have recently visited Oak Leaf Farm and come into contact with goats on the farm.  Two of the seven initial patients had subsequently developed Hemolytic Uremic Syndrome (HUS), a rare but serious illness that affects the kidneys and blood clotting system. As of today, both of those patients continue to be hospitalized.

Unclear at this point if people should have been reading www.fair-safety.com or www.realrawmilkfacts.com – or both.

The 2015 Oxford County Fair that was held in mid-September will be remembered for the death of one child and the severe illness to another due to infections with E. coli O111. The common exposure to the two children was the same petting zoo.

The investigation is ongoing, but what has appeared thus far indicates a venue that followed few of the warnings and recommendations from decades of prior outbreaks that had sickened thousands. As more information comes out over the next week on what the Fair did and did not do to prevent these families’ tragedies, the fair should be judged from health official recommended since 2001.

“Reducing the Risk for Transmission of Enteric Pathogens at Petting Zoos, Open Farms, Animal Exhibits, and Other Venues Where the Public Has Contact With Farm Animals” – 2001 CDC Recommendations:

  • Information should be provided. Persons providing public access to farm animals should inform visitors about the risk for transmission of enteric pathogens from farm animals to humans, and strategies for prevention of such transmission. This should include public information and training of facility staff. Visitors should be made aware that certain farm animals pose greater risk for transmitting enteric infections to humans than others. Such animals include calves and other young ruminant animals, young poultry, and ill animals. When possible, information should be provided before the visit.
  • Venues should be designed to minimize risk. Farm animal contact is not appropriate at food service establishments and infant care settings, and special care should be taken with school-aged children. At venues where farm animal contact is desired, layout should provide a separate area where humans and animals interact and an area where animals are not allowed. Food and beverages should be prepared, served, and consumed only in animal-free areas. Animal petting should occur only in the interaction area to facilitate close supervision and coaching of visitors. Clear separation methods such as double barriers should be present to prevent contact with animals and their environment other than in the interaction area.
  • Hand washing facilities should be adequate. Hand washing stations should be available to both the animal-free area and the interaction area. Running water, soap, and disposable towels should be available so that visitors can wash their hands immediately after contact with the animals. Hand washing facilities should be accessible, sufficient for the maximum anticipated attendance, and configured for use by children and adults. Children aged <5 years should wash their hands with adult supervision. Staff training and posted signs should emphasize the need to wash hands after touching animals or their environment, before eating, and on leaving the interaction area. Communal basins do not constitute adequate hand washing facilities. Where running water is not available, hand sanitizers may be better than using nothing. However, CDC makes no recommendations about the use of hand sanitizers because of a lack of independently verified studies of efficacy in this setting.
  • Hand-mouth activities (e.g., eating and drinking, smoking, and carrying toys and pacifiers) should not be permitted in interaction areas.
  • Persons at high risk for serious infections should observe heightened precaution. Everyone should handle farm animals as if the animals are colonized with human enteric pathogens. However, children aged <5 years, the elderly, pregnant women, and immunocompromised persons (e.g., those with HIV/AIDS) are at higher risk for serious infections. Such persons should weigh the risks for contact with farm animals. If allowed to have contact, children aged <5 years should be supervised closely by adults, with precautions strictly enforced.

“Compendium of Measures to Prevent Disease Associated with Animals in Public Settings, 2013” – National Association of State Public Health Veterinarians Animal Contact Compendium Committee 2013:

Venue operators should take the following steps:

  • Become familiar with and implement the recommendations in this compendium.
  • Consult with veterinarians, state and local agencies, and cooperative extension personnel on implementation of the recommendations.
  • Become knowledgeable about the risks for disease and injury associated with animals and be able to explain risk-reduction measures to staff members and visitors.
  • Be aware that direct contact with some animals is inappropriate in public settings, and this should be evaluated separately for different audiences.
  • Develop or obtain training and educational materials and train staff members.
  • Ensure that visitors receive educational messages before they enter the exhibit, including information that animals can cause injuries or carry organ- isms that can cause serious illness.
  • Provide information in a simple and easy-to-under- stand format that is age and language appropriate.
  • Provide information in multiple formats (e.g., signs, stickers, handouts, and verbal information) and languages.
  • Provide information to persons arranging school field trips or classroom exhibits so that they can educate participants and parents before the visit.

Venue staff members should take the following steps:

  • Become knowledgeable about the risks for dis- ease and injury associated with animals and be able to explain risk-reduction recommendations to visitors.
  • Ensure that visitors receive educational messages regarding risks and prevention measures.
  • Encourage compliance by the public with risk- reduction recommendations, especially compliance with hand-washing procedures as visitors exit animal areas.

Recommendations for nonanimal areas are as follows:

  • Do not permit animals, except for service animals, in nonanimal areas.
  • Store, prepare, serve, or consume food and beverages only in nonanimal areas.
  • Provide hand-washing facilities and display hand- washing signs where food or beverages are served.
  • Entrance transition areas should be designed to facilitate education.
  • Post signs or otherwise notify visitors that they are entering an animal area and that there are risks associated with animal contact.
  • Instruct visitors not to eat, drink, smoke, and place their hands in their mouth, or use bottles or pacifiers while in the animal area.
  • Establish storage or holding areas for strollers and related items (e.g., wagons and diaper bags).
  • Control visitor traffic to prevent overcrowding.
  • Exit transition areas should be designed to facilitate hand washing.
  • Post signs or otherwise instruct visitors to wash their hands when leaving the animal area.
  • Provide accessible hand-washing stations for all visitors, including children and persons with disabilities. Position venue staff members near exits to encourage compliance with proper hand washing.

Recommendations for animal areas are as follows:

  • Do not allow consumption of food and beverages in these areas.
  • Do not allow toys, pacifiers, spill-proof cups, baby bottles, strollers, or similar items to enter the area.
  • Prohibit smoking and other tobacco product use.
  • Supervise children closely to discourage hand-to- mouth activities (e.g., nail biting and thumb sucking), contact with manure, and contact with soiled bedding. Children should not be allowed to sit or play on the ground in animal areas. If hands become soiled, supervise hand washing immediately.
  • Ensure that regular animal feed and water are not accessible to the public.
  • Allow the public to feed animals only if contact with animals is controlled (e.g., with barriers).
  • Do not provide animal feed in containers that can be eaten by humans (e.g., ice cream cones) to decrease the risk of children eating food that has come into contact with animals.
  • Promptly remove manure and soiled animal bedding from these areas.
  • Assign trained staff members to encourage appropriate human-animal interactions, identify and reduce potential risks for patrons, and process reports of injuries and exposures.
  • Store animal waste and specific tools for waste removal (e.g., shovels and pitchforks) in designated areas that are restricted from public access.
  • Avoid transporting manure and soiled bedding through nonanimal areas or transition areas. If this is unavoidable, take precautions to prevent spillage.
  • Where feasible, disinfect the area (e.g., flooring and railings) at least once daily.
  • Provide adequate ventilation both for animals and humans.
  • Minimize the use of animal areas for public activities (e.g., weddings and dances).
  • If areas previously used for animals must be used for public events, they should be cleaned and disinfected, particularly if food and beverages are served.

A view from the Courtroom:

Under premises liability law, the entity or entities responsible for managing an animal exhibition have a duty of care to those it invites onto the premises. This duty includes the responsibility to adequately reduce risks the entity is or should be aware of. The duty also carries a responsibility to warn fairgoers of risks present at the exhibition.

The principles of negligence also revolve around the risks to fairgoers that animal exhibitors know of or reasonably should know of. To successfully bring a negligence claim, a sickened person would need to show that the actions of an animal exhibitor fell below a reasonable standard of care in the operation of the exhibit. Failing to implement the well-established recommendations of the CDC and NASPHV constitutes falling below that standard of care.

Both bases for liability on the part of animal exhibitors-premises liability and negligence-carry with them a burden of education on the part of the exhibitor. Because the law holds people to a standard of what they reasonably should know, ignorance of the risks involved is not an effective defense. The law thus provides no impetus to stray from the course of action that is best for both customers and exhibitors in the first place-recognizing the risk and taking steps to reduce it.

The following is a comprehensive description of hemolytic uremic syndrome, its symptoms, and the complications and long-term risks associated with HUS.

*** A glossary of terms can be found at the bottom of this entry. ***

Hemolytic uremic syndrome is a severe, life-threatening complication of an E. coli bacterial infection that was first described in 1955, and is now recognized as the most common cause of acute kidney failure in childhood. E. coli O157:H7 is responsible for over 90% of the cases of HUS that develop in North America. In fact, some researchers now believe that E. coli O157:H7 is the only cause of HUS in children.

HUS develops when the toxin from E. coli bacteria, known as Shiga-like toxin (SLT) [1,2], enters cells lining the large intestine. The Shiga-toxin triggers a complex cascade of changes in the blood. Cellular debris accumulates within the body’s tiny blood vessels and there is a disruption of the inherent clot-breaking mechanisms. The formation of micro-clots in the blood vessel-rich kidneys leads to impaired kidney function and can cause damage to other major organs.

What are the Symptoms associated with Hemolytic Uremic Syndrome?

About ten percent of individuals with E. coli O157:H7 infections (mostly young children) goes on to develop Hemolytic Uremic Syndrome, a severe, potentially life-threatening complication. HUS is an extremely complex process that researchers are still trying to fully explain.

The essence of Hemolytic Uremic Syndrome is described by its three central features: destruction of red blood cells (hemolytic anemia), destruction of platelets (those blood cells responsible for clotting, resulting in low platelet counts, or thrombocytopenia), and acute renal failure. In HUS, renal failure is caused when the nephrons, or filtering units, become occluded (blocked) by micro-thrombi, which are tiny blood clots. In almost all cases, the filtering ability of the kidneys recovers as the body of the patient slowly dissolves the micro-thrombi within the microvessels.

A typical person is born with about one million filtering units, called nephrons, in each kidney. The core of the nephron is a bundle of tiny blood vessels, called a glomerulus, where osmotic exchange allows for the filtration of wastes that eventually collect in the urine and are excreted. During Hemolytic Uremic Syndrome, the lack of blood flow to the nephrons can cause them to die or be damaged, just as heart muscle can die as the result of coronary vessel occlusion during a heart attack. Dead nephrons do not regenerate.

In general, the longer a patient suffers kidney failure, the greater the loss of filtering units as a result. At some point, the damage to the kidneys’ filtering units can be so severe that the patient will, over a period of years, lose kidney function and suffer end-stage renal disease (ESRD), which requires chronic dialysis or transplantation.

HUS can also cause transient or permanent damage to other organs, which include the pancreas, liver, brain, and heart. The essential pathogenic process is the same regardless of the organ affected: microthrombi inhibit necessary blood flow and cause tissue death or damage. During the acute stage of Hemolytic Uremic Syndrome, patients must be carefully monitored for these extra-renal complications. It is very difficult to predict the severity and course of HUS once it initiates.

The active stage of Hemolytic Uremic Syndrome may be defined as that period of time during which there is evidence of hemolysis and the platelet count is less than 100,000. In HUS, the active stage usually lasts an average of six days (range, 2-16 days). It is during the active stage that the complications of HUS per se usually occur.

What are the complications and long-term risks associated with Hemolytic Uremic Syndrome?

Several studies have demonstrated that children with HUS who have apparently recovered will develop hypertension, urinary abnormalities and/or renal insufficiency during long-term follow-up.

End Stage Renal Disease, Dialysis and Kidney Transplantation

End Stage Renal Disease

Children and adolescents with chronic renal failure face a number of complications from the condition, including alterations in calcium and phosphate balance and renal osteodystrophy (softening of the bones, weak bones and bone pain), anemia (low blood cell count that leads to a lack of energy), growth failure (final height as an adult substantially below normal), hypertension (high blood pressure), and other complications.

Renal osteodystrophy (softening of the bones) is an important complication of chronic renal failure. Bone disease is nearly universal in patients with chronic renal failure; in some children, symptoms are minor to absent while others may develop bone pain, skeletal deformities and slipped epiphyses (abnormal shaped bones and abnormal hip bones) and have a propensity for fractures with minor trauma. Treatment of the bone disease associated with chronic renal failure includes control of serum phosphorus and calcium levels with restriction of phosphorus in the diet, supplementation of calcium, the need to take phosphorus binders, and the need to take medications for bone disease.

Anemia is a very common complication of chronic renal failure. The kidneys make a hormone that tells the bone marrow to make red blood cells and this hormone is not produced in sufficient amounts in children with chronic renal failure. Thus, children with chronic renal failure gradually become anemic while their chronic renal failure is slowly progressing. The anemia of chronic renal failure is treated with human recombinant erythropoietin (a shot given under the skin one to three times a week or once every few weeks with a longer acting human recombinant erythropoietin).

Growth failure ultimately leading to short height as an adult is a very common complication of chronic renal failure in children. The mechanisms of growth failure are complex and due to multiple causes. Poorly controlled renal osteodystrophy (bone disease), inadequate nutrition (insufficient intake of adequate calories), chronic acidosis (blood system too acid) and abnormalities of the growth hormone axis (growth hormone deficiency) are each major contributors to poor growth in the child with chronic renal failure. Growth hormone therapy with human recombinant growth hormone has been approved for use in children with chronic renal failure and such therapy has been shown to accelerate growth, induce persistent catch up growth and lead to normal adult height in children with chronic renal failure. Growth hormone therapy requires giving a shot under the skin once a day. Complications of growth hormone therapy are rare but may include glucose intolerance and exacerbation of poorly controlled renal osteodystrophy.

Dialysis and Kidney Transplantation

Renal replacement therapy can be in the form of dialysis (peritoneal dialysis or hemodialysis) or renal transplantation.

If the patient does not have a living related donor for their first kidney transplant and when they need a second kidney transplant after loss of the first transplant, they will need dialysis until a subsequent transplant can be performed. The patient can be on peritoneal dialysis or on hemodialysis.

Peritoneal dialysis has been a major modality of therapy for chronic renal failure for several years. Continuous Ambulatory Peritoneal Dialysis (CAPD) and automated peritoneal dialysis also called Continuous Cycling Peritoneal Dialysis (CCPD) are the most common forms of dialysis therapy used in children with chronic renal failure. In this form of dialysis, a catheter is placed in the peritoneal ca
vity (area around the stomach); dialysate (fluid to clean the blood) is placed into the abdomen and changed 4 to 6 times a day. Parents and adolescents are able to perform CAPD/CCPD at home. Peritonitis (infection of the fluid) is a major complication of peritoneal dialysis.

Hemodialysis has also been used for several years for the treatment of chronic renal failure during childhood. During hemodialysis, blood is taken out of the body by a catheter or fistula and circulated in an artificial kidney to clean the blood. Hemodialysis is usually performed three times a week for 3-4 hours each time in a dialysis unit.

Renal transplantation can be from a deceased or a living related donor (parent or sibling who is over the age of 18 who is compatible). Should the patient have a living related donor available to donate a kidney, they can undergo transplantation without the need for dialysis (preemptive transplantation). Should they not have a living related donor, they will likely need to undergo dialysis while on the waiting list for a deceased donor transplant. Fortunately, children have the shortest waiting time on the deceased donor transplant list. The average waiting time for children age 0-17 years is approximately 275-300 days while the average waiting time for patients age 18-44 years is approximately 700 days.

Following transplantation, the patient will need to take immunosuppressive medications for the remainder of their life to prevent rejection of the transplanted kidney. Medications used to prevent rejection have considerable side effects. Corticosteroids are commonly used following transplantation. The side effects of corticosteroids are Cushingnoid features (fat deposition around the cheeks and abdomen and back), weight gain, emotional liability, cataracts, decreased growth, osteomalacia and osteonecrosis (softening of the bones and bone pain), hypertension, acne and difficulty in controlling glucose levels. The steroid side effects, particularly the effects on appearance, are difficult for children, especially teenagers, and non compliance do to the side effects of medications is a risk in children; again, particularly teenagers.

Cyclosporine and/or tacrolimus are also commonly used as immunosuppressive medications following transplantation. Side effects of these drugs include hirsutism (increased hair growth), gum hypertrophy, interstitial fibrosis in the kidney (damage to the kidney), as well as other complications. Meclophenalate is also commonly used after transplantation (sometimes imuran is used); each of these drugs can cause a low white blood cell count and increased susceptibility to infection. Many other immunosuppressive medications and other medications (anti-hypertensive agents, anti-acids, etc) are prescribed in the post operative period.

Life long immunosuppression, as used in patients with kidney transplants, is associated with several complications including an increased susceptibility to infection, accelerated atherosclerosis (hardening of the arteries), increased incidence of malignancy (cancer) and chronic rejection of the kidney.

United States Renal Data Systems (USRDS) report that the half-life (time at which 50% of the kidneys are still functioning and 50% have stopped functioning) is 10.5 years for a deceased transplant in children age 0-17 years and 15.5 years for a living related transplant in children 0-17 years. Similar data for a transplant at age 18 to 44 years is 10.1 years and 16.0 years for a deceased donor and a living related donor, respectively. Thus, depending upon the age when the patient receives their first transplant they may need 2-3 transplants over the course of their life.

Thus, the life expectancy of a person with a kidney transplant is significantly less than the general population and the life expectancy of a person on dialysis is markedly less than the general population.

Hemolytic uremic syndrome patient follow-up.

Children who appear to have recovered from HUS may develop late complications. A precise determination of the risk of late complications is not likely. It is important to note that the risks of longer term (more than 20 years) complications are unknown and are likely to be higher than risks at 10 years, as many of the above studies describe.

All persons who have experienced HUS should be formally evaluated by a nephrologist—a kidney specialist—at a year following their acute illness. Kidneys injured by HUS may slowly recover function over at least a six month period following the acute episode and perhaps longer. Even persons with “mild” HUS who did not require dialysis should be formally evaluated. Such an evaluation should include a routine physical, blood pressure measurement, and blood and urine analyses from which kidney filtration rate can be calculated.

Studies done to date on HUS outcomes have largely confirmed a positive correlation between more severe kidney involvement acutely, particularly the need for extended dialysis, and increased incidence of future renal complications. However, it has been shown in multiple studies that even moderate kidney compromise in the acute phase of HUS can result in long-term complications due to damage to the filtering units in the kidneys.

Among survivors of HUS, estimates are that about five percent will eventually develop end stage kidney disease, with the resultant need for dialysis or transplantation, and another five to ten percent experience neurological or pancreatic problems which significantly impair quality of life. Since the longest available follow-up studies of HUS are about twenty (20) years, an accurate lifetime prognosis is not available, and as such, medical follow-up is indicated for even the mildest affected cases.

[1] Recent research suggests that E. coli O157:H7 acquired its pathological character when a bacteriophage (virus that infects bacteria) transmitted genetic material for the creation of the toxin from a closely related Shigella bacterial species (hence the epithet, Shiga-like toxin) to a formerly benign species of E. coli.

[2] Verotoxin-globotriaosyl ceramide binding receptors.

Glossary of terms

  1. allograft: a graft derived from an individual of the same species that is sufficiently unlike genetically to interact antigenically
  2. antagonist: in biochemistry, an antagonist acts against and blocks an action.
  3. anticoagulant: any agent used to prevent the formation of blood clots.
  4. antigen: a protein or carbohydrate substance (as a toxin or enzyme) capable of stimulating an immune response
  5. antibody titers: a measure of proteins of high molecular weight that are produced normally after stimulation by an antigen and act specifically against the antigen in an immune response
  6. anuria: absence of urine excretion
  7. case fatality rate: the proportion of deaths among a group of persons with a particular condition or disease
  8. basal ganglia: a region consisting of 3 clusters of neurons located at the base of the brain that are responsible for involuntary movements
  9. C-reactive protein: a special type of protein produced by the liver that is only present during episodes of acute inflammation
  10. CT scan: A computerized axial tomography scan is more commonly known by its abbreviated name, CAT scan or CT scan; an x-ray procedure which combines many x-ray images with the aid of a computer to generate cross-sectional views and, if needed, three-dimensional images of the internal organs and structures of the body
  11. cortical necrosis: tissue death of the outer layer of the kidney
  12. creatinine: a chemical waste molecule that is generated from muscle metabolism and transported through the bloodstream to the kidneys. The kidneys filter out most of the creatinine and dispose of it in the urine. As the kidneys become impaired, the creatinine will rise.
  13. dialysis/hemodialysis: process of removing blood from an artery to purify it (remove wastes or toxins from the blood) and adjust fluid and electrolyte imbalances, adding vital substances, and returning it to a vein (see also peritoneal dialysis)
  14. double-blinded study: A study in which neither the study groups nor the evaluator are aware of who receives the experimental treatment or procedure versus the placebo or comparison treatment
  15. dysphasia: difficulty in swallowing
  16. effective renal plasma flow (ERPF): the amount of plasma flowing through the kidney tubules per unit time; differentiated from renal plasma flow which is approximately 10% greater than ERPF
  17. electroencephalograph (EEG): an apparatus for detecting and recording brain waves
  18. end-stage renal disease (ESRD): the final stages of a terminal kidney disease or condition when there is complete or near complete failure of the kidneys to function
  19. etiology: the cause of a disease
  20. fibrinolytics: clot-dissolving drugs
  21. gastric: relating to the stomach
  22. genotype: the genetic constitution (the genome) of a cell, an individual or an organism.
  23. glomerular: pertaining to the glomerulus, a tiny structure in the kidney that filters the blood to form urine.
  24. glomerular filtration rate (GFR): the rate at which blood is filtered through tufts of capillaries in the kidney
  25. glomerulonephritis: a disorder that causes inflammation of the internal kidney structures (specifically, the glomeruli); it may be a temporary and reversible condition, or it may be progressive.
  26. graft: placing tissue or organs from one area on the body or from another person or an animal into the patient’s body; in this case transferring a kidney from one person to another
  27. hemiparesis: muscular weakness or partial paralysis restricted to one side of the body
  28. hemolytic anemia: anemia caused by excessive destruction (as in chemical poisoning, infection, or sickle-cell anemia) of red blood cells
  29. hemorrhagic colitis: bloody infection/inflammation of the colon (bowel)
  30. histological: in reference to the minute structure of tissues discernible with the microscope
  31. hyperfiltration: abnormal increase in the filtration rate of the renal glomeruli
  32. hypertension: high blood pressure
  33. hyponatremia: deficiency of sodium (salt) in the blood
  34. infarct/infarction: an area of necrosis (death) in a tissue or organ resulting from obstruction of the local circulation by a thrombus or embolus
  35. internal/external capsule: fibrous express ways that contain nerves to transmit information within certain parts of the brain
  36. in vitro: outside the living body and in an artificial environment
  37. intravenous (IV): within a vein
  38. ischemia: localized tissue anemia due to obstruction of the inflow of arterial blood (as by the narrowing of arteries by spasm or disease)
  39. leukocyte: white blood cell
  40. leukocytosis: increase in the number of white blood cells
  41. microangiopathy: a disease of very fine blood vessels
  42. microvascular: of, relating to, or constituting the part of the circulatory system made up of minute vessels (as venules or capillaries) that average less than 0.3 millimeters in diameter
  43. monoclonal antibody: an antibody derived from a single cell in large quantities for use against a specific antigen
  44. morbidity: the incidence of disease; the rate of sickness (as in a specified community or group)
  45. morphologic: of, relating to, or concerned with form or structure
  46. mortality: the number of deaths in a given time or place; the proportion of deaths in a given population
  47. MRI/magnetic resonance imaging: a radiology technique using magnetism, radio waves, and a computer to produce images of body structures
  48. nephrotic syndrome: a constellation of signs and symptoms including protein in the urine, low blood protein levels, high cholesterol levels, and swelling; results in damage to the kidneys, particularly the basement membrane of the glomerulus
  49. neutrophil: type of white blood cell, filled with neutrally-staining granules, tiny sacs of enzymes that help the cell to kill and digest microorganisms it has engulfed
  50. oliguria: reduced excretion of urine
  51. parenteral: drug or substance, like supplementary nutrition, administration by intravenous, intramuscular, or subcutaneous injection; especially introduced other than by way of the intestines
  52. paresis: paralysis
  53. pathogenesis: the origin of a disease and the chain of events leading to that disease.
  54. peritoneal dialysis: technique that uses the patient’s own body tissues inside of the belly (abdominal cavity) to act as a filter to remove waste products and excess water from the body
  55. placebo: an inert or harmless substance used especially in controlled experiments testing the efficacy of another substance (as a drug)
  56. plasmapheresis: separating out the plasma from the whole blood, replacing the plasma, and returning plasma and original blood cells to the patient
  57. platelet: An irregular, disc-shaped element in the blood that assists in blood clotting. During normal blood clotting, the platelets clump together.
  58. primary: first in order of time or development
  59. prodromal: a symptom or set of symptoms that occur before the onset of a disease or condition
  60. proteinuria: protein in the urine
  61. prothrombotic: a substance which encourages the production of blood clots
  62. randomized: things or persons put in a random order so that every thing or person is equally likely to be selected; study subjects are randomly distributed into groups which are either subjected to the experimental procedure (or use of a drug) or which serve as controls.
  63. receptor: a structure on the surface of a cell (or inside a cell) that selectively receives and binds a specific substance.
  64. rectal prolapse: the falling down or slipping of a the rectum (the terminal part of the intestine) from its usual position
  65. renal: kidney
  66. retina: the sensory membrane that lines most of the large posterior chamber of the eye; functions as the immediate instrument of vision by receiving the image formed by the lens and converting it into chemical and nervous signals which reach the brain by way of the optic nerve
  67. sequelae: an after effect of disease, injury, procedure, or treatment
  68. serotype/group: a group of intimately related microorganisms distinguished by a common set of antigens
  69. Shiga toxin/Stx: a poisonous product of the E. coli organism; toxins are usually very unstable and can cause damage to cells. Toxins typically induce antibody formation.
  70. sodium: the major positive ion (cation) in fluid outside of cells. When combined with chloride, the resulting substance is table salt. Excess sodium is excreted in the urine. Too much or too little sodium can cause cells to malfunction.
  71. stupor: decreased mental status or consciousness; loss of alertness
  72. tetraspastic: a state of hypertonicity or increase over the normal tone of a muscle, with heightened deep tendon reflexes, affecting all four extremities
  73. thalamus/thalami: the part of the brain that serves to relay impulses and especially sensory impulses to and from the cerebral cortex (the gray matter of the cerebrum that functions chiefly in coordination of sensory and motor information)
  74. thrombocytopenia: persistent decrease in the number of blood platelets that is often associated with hemorrhagic conditions — called also thrombopenia
  75. thrombogenic: tending to produce a thrombus (a clot of blood formed within a blood vessel and remaining attached to its place of origin)
  76. thrombosis: the formation or presence of a blood clot within a blood vessel
  77. thrombotic thrombocytopenic purpura (TTP): a blood disorder characterized by low platelets, low red blood cell count (caused by premature breakdown of the cells), abnormalities in kidney function, and neurological abnormalities; caused by a deficiency in the von Willebrand Factor cleaving protease, known as ADAMTS13. The loss of this enzyme results in large complexes of von Willbrand factor circulating in the blood, which in turn causes platelet clumping and red blood cell destruction.
  78. vascular endothelial growth factor: substance made by cells that stimulates new blood vessel formation
  79. white matter: neural tissue that consists largely of myelinated (sheathed) nerve fibers, has a whitish color, and underlies the gray matter of the brain and spinal cord or is gathered into nerves