Intra-abdominal infections

Definition - types and causes- risk factors - diagnosis - treatment of intra-abdominal infections

1. INTRA-ABDOMINAL INFECTIONS Dr. Sameh Ahmad Muhamad abdelghany Lecturer Of Clinical Pharmacology Mansura Faculty of medicine

2. Intra- abddominal Infections INTRODUCTION      TYPES RISK FACTORS Diagnosis Treatment CONTENTS

3. OBJECTIVES Describe pathogenesis & clinical characteristics of intra-abdominal infections Identify most likely etiologic organism(s) Review appropriate drug therapy

4. Definition

5. INTRA-ABDOMINAL INFECTIONS Infections contained within the peritoneum or retroperitoneal space. Peritoneal cavity contains: Stomach Jejunum, Ileum Appendix Large intestine (colon) Liver, gallbladder and spleen Retroperitoneal space: Duodenum Pancreas Kidneys

6. INTRA-ABDOMINAL INFECTIONS Peritonitis Intra-abdominal Abscess Appendicitis Diverticulitis Antibiotic-Associated Diarrhea Food Poisoning/Traveler’s Diarrhea Helicobacter pylori Pelvic Inflammatory Disease Viral Parasitic

7. Anatomy of GIT

8. GIT Microflora Stomach: Helicobacter pylori Streptococci Lactobacilli Upper Intestine: Aerobes Streptococci (Enterococci) Staphylococci Lactobacilli E. coli, Klebsiella Anaerobes Bacteroide s

9. GIT Microflora Ileum: Aerobes: Streptococci Staphylococci Escherichia coli,Klebsiella Enterobacter Anaerobes: Bacteroides Clostridium

10. GIT Microflora Colon: Anaerobes: Bacteroides Peptostreptococci Clostridium Bifidobacteria Aerobes: Escherichia coli, Klebsiella Enterobacter Streptococci (Enterococci) Staphylococci

11. GIT Microflora Intra-abdominal infections result in 2 major clinical manifestations Early or diffuse infection results in localized or generalized peritonitis. Late and localized infections produces an intra-abdominal abscess.

12. PERITONITIS

13. Peritonitis Inflammation of the serous lining of the peritoneal cavity due to: Microorganisms Chemicals Irradiation Foreign body injury

14. Peritonitis TYPES Primary (Spontaneous Bacterial Peritonitis) Secondary Tertiary

15. Primary Peritonitis Relatively infrequent 25% of patients with alcoholic cirrhosis 60% of all patients on chronic ambulatory peritoneal dialysis (CAPD) will have at least one episode in 1st year. Average incidence in CAPD patients is 1.3 to 1.4 episodes/yr. Catheter connecting abdominal cavity to exterior body is a major risk factor

16. Primary Peritonitis No focus of disease is evident Arises without a breach in the peritoneal cavity or GIT Bacteria transported from blood stream to peritoneal cavity (Cirrhosis, CAPD) Usually monomicrobial

17. Primary Peritonitis Usually occurs in people who have an accumulation of fluid in their abdomens (ascites). The fluid that accumulates creates a good environment for the growth of bacteria.

18. Primary Peritonitis Common Bacteria: Escherichia coli Streptococci Enterococci Klebsiella Staphylococci (CAPD patients) Pseudomonas aeruginosa Bacteroides sp.

19. Secondary Peritonitis Caused by the entry of bacteria or enzymes into the peritoneum from the gastrointestinal or biliary tract. This can be caused due to : an ulcer eating its way through stomach wall intestine when there is a rupture of the appendix a ruptured diverticulum.

20. Secondary Peritonitis Also, it can occur due to burst or injury to an internal organ which bleeds into the internal cavity. Community acquired or nosocomial Usually polymicrobial

21. Tertairy Peritonitis Peritonitis in a critically ill patient which persists or recurs at least 48 h after apparently adequate management of primary or secondary peritonitis

22. Risky of Peritonitis Peritonitis is very serious & can be life threatening if not treated properly!!!

23. RISK FACTORS

24. Risk Factors Risk factors for Primary Peritonitis: Liver disease (cirrhosis) Fluid in the abdomen Weakened immune system Pelvic inflammatory disease

25. Risk Factors Risk factors for secondary peritonitis include : Appendicitis (inflammation of the appendix) Stomach ulcers, Twisted intestine, Pancreatitis Inflammatory bowel disease Injury caused by an operation. Peritoneal dialysis, Trauma.

26. DIAGNOSIS

27. CLINICAL PICTURE Abdominal pain Anorexia, Nausea/Vomiting Loss of Appetite Fever (38-40 ºC) Abdominal distention and tenderness Hypoactive or faint bowl sounds Leukocytosis

28. CLINICAL PICTURE Shallow Breaths Low BP Limited Urine Production Inability to pass gas or feces

29. CLINICAL PICTURE An acutely ill patient tends to lie “very” still because any movement causes excruciating pain. They will lie with there knees bent to decrease strain on the tender peritoneum.

30. Physical Examination Detect any swelling & tenderness in the area as well as signs of fluid has collected in the area. Listen to the bowel sounds & check for difficulty breathing Low blood pressure signs of dehydration.

31. Physical Examination The abdomen may be rigid and boardlike Accumulations of fluid will be notable in primary due to ascites.

32. Peritonitis

33. INVESTIGATIONS Blood Test Samples of fluid from the abdomen CT Scan Chest X-rays Peritoneal lavage

34. INVESTIGATIONS Peritoneal Fluid Analysis Normally: 20 to 50 mL transudate Peritoneal membrane measures approx. 1.7 metres square WBC < 300 cells/mm3 Protein: <3 g/ dL Bacterial peritonitis: 300 to 500mL inflow/ hr resulting in hypovolemia. WBC > 300 cells/mm3 Gram stain + for bacteria

35. INVESTIGATIONS Microbiology Blood cultures often – ve Peritoneal fluid used (paracentesis) Health care associated intra-abdominal infection usually due to nosocomial organisms particular to the site of the operation and specific hospital and unit

36. Prognosis Untreated peritonitis is poor, usually resulting in death. With Tx, prognosis is variable, dependent on the underlying causes.

37. Peritonitis

38. Peritonitis

39. INTRA-ABDOMINAL ANBCESS

40. Intra – abdominal Abscess Result from chronic inflammation and often occur without generalized peritonitis. Located within peritoneal cavity or visceral organs. May range from a few milliliters to a liter in volume. Often have a fibrinous capsule and take days to yrs to form. Appendicitis is the most common cause. Ultrasound or CT scan may be used for evaluation

41. Intra – abdominal Abscess Common Bacteria: E. coli Klebsiella Enterococci B. fragilis Clostridium

42. CLINICAL PICTURE Symptoms less dramatic than peritonitis +/- pain +/- fever +/- abdominal distention

43. Complication Ruptured abscess Spread of bacteria + toxins into peritoneum - peritonitis Spread of bacteria + toxins into systemic circulation – sepsis, multi-organ failure, death

44. INVESTIGATIONS Labs: Leukocytosis +/- positive blood cultures +/-hyperglycemia Ultrasound, GI contrast study, or CT scan may be used for evaluation

45. Intra – abdominal Abscess

46. TREATMENT

47. Treatment of Intra-abdominal Infections Combination of modalities: Surgical : Prompt drainage of abscess (secondary peritonitis) and/or debridement, Resection of perforated colon, small intestine, ulcers Repair of trauma.

48. Treatment of Intra-abdominal Infections Support of Vital functions : Blood pressure/fluid replacement, Monitor heart rate Monitor urine out put (0.5 ml/kg/ hr ) Appropriate antimicrobial therapy

49. Antibiotic Therapy Empiric Antibiotic Therapy MUST include aerobic/anaerobic coverage Aerobic and Anaerobic activity Ampicillin/sulbactam ( Unasyn ) (enterococci) Piperacillin/tazobactam (Zosyn) (enterococci) Cefotetan (Cefotetan) Cefoxitin ( Mefoxin ) Imipenem/ cilastin ( Primaxin ) Meropenem ( Merrem ) Moxifloxacin ( Avelox )

50. Antibiotic Therapy Empiric Antibiotic Therapy MUST include aerobic/anaerobic coverage Anaerobic activity Chloramphenicol( also includes aerobic Gram +/-) Clindamycin (also includes aerobic Gram +) Metronidazole (anaerobic coverage only)

51. Antibiotic Therapy Empiric Antibiotic Therapy MUST include aerobic/anaerobic coverage Aerobic activity Aminoglycosides: gentamicin, tobramycin (Gram negatives only) Beta-lactams: Cefotaxime ( Claforan ) Ceftriaxone (Rocephin) Aztreonam ( Azactam ) (Gram negative only) Quinolones: Ciprofloxacin (Cipro) (Mostly Gram negative) Levofloxacin (Levaquin) (Gram +/- and some anaerobic coverage) Vancomycin/Linezolid (Enterococci, MRSA)

52. Antibiotic Therapy Factors involved in selection: Severity of infection, suspected infecting organism(s) and resistance patterns, efficacy, toxicity (renal dysfunction),allergies. Evaluating response: Improvement in 2 to 3 days Switch for oral antibiotic therapy Failure to improve: Resistant organisms Recurrent surgical infections Other infections: (urinary tract infections, pneumonia)

53. APPENDECITIS

54. Appendicitis Highest incidence 10-19y/o Male > female Pathophysiology: Relationship to onset of signs 0-24h after signs onset: obstruction within appendix , inflammation & occlusion of vascular & lymphatic flow, bacterial overgrowth then necrosis. >48h after signs onset: perforation, abscess/peritonitis

55. Appendicitis

56. CLINICAL PICTURE Early sign : dull, non-localized pain Indigestion bowel irregularity flatulence

57. CLINICAL PICTURE Later signs: pain/tenderness more localized N/V Fever > 39 degrees celcius leukocytes >15000 perforation likely

58. Management Treatment :Both surgical & Antibiotics Acute, non-perforated appendicitis cefazolin + metronidazole Perforated appendicitis Anti-anaerobic cephalosporin (e.g. Cefotetan, Cefoxitin, Piperacillin/tazobactam, Ampicillin/sulbactam, Imipenem Combination therapy: Aminoglycoside +/- Clindamycin or Metronidazole Antibiotics are started before surgery, continued for 7- 10 days.

59. Antibiotic Associated Diarrhea

60. Antibiotic Associated Diarrhea Antibiotic therapy (broad spectrum agents: Clindamycin Ampicillin 3rd generation cephalosporins

61. Pseudomembranous Colitis Clostridium difficile: toxin mediated disease Toxin A (major) and B (minor): cause inflammation, necrosis, loss of fluid electrolytes Associated with broad spectrum antibiotics

62. Pseudomembranous Colitis Patients may develop diarrhea after 3 or more days of hospitalization or within 2 months of antibiotic therapy. 3 to 5% of adults are carriers of C. difficile Recurrence in 7 to 20% of patients.

63. Pseudomembranous Colitis Treatment FIRST LINE: Metronidazole (Treatment of Choice) 250mg PO QID or 500mg PO/IV TID x 10-14 days ALTERNATIVE: (if pregnant, not responding to metronidazole or recurrences) Vancomycin 125mg PO QID x 10-14 days +/- rifampin 600mg PO BID Always stop the drug responsible for causing the infection as soon as possible!

64. Pseudomembranous Colitis

65. thanks For Watching