1. A 34 y/o man with abdominal pain Pamela Ryan MD February 8, 2006

2. A 34 y/o man with abdominal pain 34 y/o male HIV positive, CD4 545, on HAART 1 week h/o severe abdominal pain, nausea, and low grade fevers. No melena, no hematochezia. No travel, no pets, no sick contacts. + Reported chronic history of “4-6 loose stools/day”—but recently increased to 8-10 stools/day.

3. A 34 y/o man with abdominal pain PMHx –HIV/AIDS, CD4 nadir of 44. Currently 545. –History of thrush, with possible esophageal candidiasis –Depression –Anxiety

4. A 34 y/o man with abdominal pain Meds: –Truvada (Emtricitabine/Tenofovir) –Kaletra (Lopinavir/Ritonavir) Social Hx –Hairdresser –Long term relationship with his male partner of several years. –Smokes cigarettes—2 ppd –H/o marijuana use

5. A 34 y/o man with abdominal pain Physical Exam –T 98.9 BP 115/74 P 84 RR 18 –Thin male in mild distress –No rashes, no lymphadenopathy –Abd: Bowel sounds present. Diffusely tender. Distended. No rebound or guarding. Heme positive stool.

6. Abdominal plain film “Multiple dilated loops of small bowel which may represent a mechanical obstruction at the level of the ileocecal valve, an adynamic ileus, or an infectious enteritis.”

7. Labs WBC 6.6, Hct 46, Platelets 146K CD4 575 Lytes all WNL LFT’s, amylase, lipase –all within normal limits

8. CT scan Abdominal and Pelvic CT Severe inflammatory changes of the cecum and hepatic flexure with associated submucosal bowel wall edema and thickening.

9. Thoughts? Diarrhea and abdominal pain in HIV male…..

10. Diarrhea in HIV affected individuals Kaposi’s sarcoma of the stomach or intestine. Medications (nelfinavir) HIV infection of the GI tract Lymphoma Infectious (pathogen may vary with the degree of immunocompromise of the patient) Inflammatory bowel disease

11. ©2006 UpToDate ® ©2006 UpToDate ® www.uptodate.com Contact Uswww.uptodate.comContact Us

12. Further Labs Micro/Stool studies –Cryptosporidium negative –Isospora negative –C. Diff toxin positive –Shiga toxin positive –Positive fecal leukocytes.

13. Objectives Discuss E. Coli O157 –Epidemiology –Pathogenesis –Clinical Manifestations –Potential complications of illness –Treatment.

14. E. Coli O157:H7 1982—2 outbreaks of severe bloody diarrhea in 47 individuals. CDC demonstrated that all of the infected individuals had ingested ground beef from the same fast food restaurant.

15. Epidemiology GI tract of cattle—excreted by up to 10% of healthy cattle. Person to person. Secondary attack rate is 10-22%, particularly in daycare centers and nursing homes. More common in the North than the South and 2/3 of cases occur in the summer.

16. Figure Also found in the stool of sheep, goats, and deer. –Several documented outbreaks associated with petting zoos

17. Epidemiology Contamination occurs when the intestinal contents from an infected animal contacts the beef. 1% of retail ground beef in US are culture positive. Substantial mixing of meat…. Can also be transmitted by food that has been fecally contaminated (apples, lake or drinking water)

18. Epidemiology Retrospective review looking at mechanism of exposure (Emerging Infectious Disease 2005; 11 ;603) 8598 cases from 49 states between 1982 and 2002 –Foodborne (52%) –Person to person (14%) –Waterborne (9%) –Animal contact (3%) –Unknown (22%)

19. E. Coli O157:H7 Pathogenesis: –Infectious dose is only 10-100 organisms (very low), compared to other enteric pathogens –Salmonella 10 (5) to 10 (8) organisms, Campylobacter jejuni 10 (4) to 10 (6). slight undercooking, leaving a small number of residual organisms. –Therefore, a successful infection only requires slight undercooking, leaving a small number of residual organisms.

20. E. Coli O157:H7 Shiga toxin: responsible for the vascular damage (hemorrhagic colitis) and for the systemic effects (HUS) Hemolytic Uremic Syndrome –Renal failure, microangiopathic hemolytic anemia, and thrombocytopenia.

21. Clinical Manifestations Incubation period is 3-4 days. Bloody stool, striking abdominal pain, and tenderness. Often no fever. Hemolytic-uremic syndrome (possible complication) –Most commonly occurs in young children –Acute renal failure, microangiopathic hemolytic anemia, and thrombocytopenia. –If diarrhea continues longer than 4-5 days, check a CBC.

22. Diagnosis Suspect in all patients with acute bloody diarrhea. Our lab Culture 95% of cultures positive for E. Coli O157:H7 come from patients with visibly bloody stools.

23. Treatment Supportive, monitor for HUS. Avoid antiperistaltics Early studies suggested antibiotic therapy (particularly tmp/sulfa or beta lactams) following infection increased the risk of HUS. 2002 meta-analysis was not able to document a relationship between antibiotics and HUS in adults. (Safdar JAMA 2002)

24. An ounce of prevention… Association with undercooked ground beef. “A significant proportion of ground beef patties are brown in the middle before they have reached an internal temperature high enough to kill E. Coli 0157 (160 degrees F).” Avoid unpasteurized juices and milk, and wash all fresh produce thoroughly.

25. Patient f/u Prolonged hospital course—developed pancolitis. Was treated with Cipro and Flagyl. Did not require surgery. He is doing well now.

26. Bibliography Rangel, et al. Epidemiology of Escherichia coli 0157:H7 outbreaks, United States, 1982-2002. Emerg Infect Dis 2005; 11:603. Safdar, N., Said A, Gangnon, Maki. Risk of hemolytic uremic syndrome after antibiotic treatment of Escherichia coli 0157:H7 enteritis. JAMA 2002; 288:996. MMWR Weekly Dec 23, 2005/54(50);1277- 1280.