Immunology/InfectionImmunology/Infection

• The most common acquired hospital infection is:• A. Pneumonia• B. Blood stream infection• C. Urinary tract infection• D. Colitis

• The most common acquired hospital infection is:• A. Pneumonia• B. Blood stream infection• C. Urinary tract infection• D. Colitis• Most common acquired hospital infection is UTI• This is often related to placement of urinary catheters• The best treatment of a UTI is removal of the catheter

• The most common cause of bloodstream infection:• A. UTI• B. Pneumonia• C. Colitis• D. Central line sepsis

• The most common cause of bloodstream infection:• A. UTI• B. Pneumonia• C. Colitis• D. Central line sepsis• The most common cause of blood stream infection is central

line sepsis. When a pt. spikes a fever send off blood, urine, and sputum Cx, Check the wound and a CXR, send a CBC.

• The mechanism of aminoglycoside resistance is:• A. Plasmids for beta-lactamase• B. Changes in cell wall binding protein• C. Decreased active transport due to modifying enzymes• D. Enhanced metabolism of the bacteria

• The mechanism of aminoglycoside resistance is:• A. Plasmids for beta-lactamase• B. Changes in cell wall binding protein• C. Decreased active transport due to modifying enzymes• D. Enhanced metabolism of the bacteria• Active transport of aminoglycosides is decreased by

modification of the transport proteins by enzymes

• The mechanism of penicillin resistance is:• A. Plasmids for beta-lactamase• B. Changes in cell wall binding protein• C. Decreased active transport due to modifying enzymes• D. Enhanced metabolism of the bacteria

• The mechanism of penicillin resistance is:• A. Plasmids for beta-lactamase• B. Changes in cell wall binding protein• C. Decreased active transport due to modifying enzymes• D. Enhanced metabolism of the bacteria• The usual mechanism of PCN resistance is by plasmids

coding for beta-lactamase• The mechanism of vancomycin resistance is changes in cell

wall binding protein

• Appropriate vancomycin peak and trough values are:• A. Peak 20-40, trough 5-10• B. Peak 5-10, trough <1• C. Peak 40-80, trough 20-40• D. Peak <1, trough 5-10

• Appropriate vancomycin peak and trough values are:• A. Peak 20-40, trough 5-10• B. Peak 5-10, trough <1• C. Peak 40-80, trough 20-40• D. Peak <1, trough 5-10• The appropriate peak (20-40) and trough (5-10) values for

vancomycin are important in pts. With renal failure

• Appropriate gentamicin peak and trough values are:• A. Peak 20-40, trough 5-10• B. Peak 5-10, trough <1• C. Peak 40-80, trough 20-40• D. Peak <1, trough 5-10

• Appropriate gentamicin peak and trough values are:• A. Peak 20-40, trough 5-10• B. Peak 5-10, trough <1• C. Peak 40-80, trough 20-40• D. Peak <1, trough 5-10• The appropriate peak (5-10) and trough (<1) values for

gentamicin are important in pts. with renal failure

• A pt. on gentamicin has a peak level of 80 and a trough of <1. The most appropriate management is:

• A. Continue current dosing• B. Decrease dose but maintain frequency • C. Decrease dose and decrease frequency• D. Maintain dose and decrease frequency

• A pt. on gentamicin has a peak level of 80 and a trough of <1. The most appropriate management is:

• A. Continue current dosing• B. Decrease dose but maintain frequency • C. Decrease dose and decrease frequency• D. Maintain dose and decrease frequency• To decrease the peak level of a drug, decrease the dose of

the drug (peak level is taken 1 hour after dosing)• To decrease the trough of a drug, decrease the frequency

or longer time b/t doses

• A pt. w/ an enterococcal blood stream infection is best treated by which of the following antibiotics:

• A. Cefazolin• B. Ceftriaxone• C. Bactrim• D. Ampicillin

• A pt. w/ an enterococcal blood stream infection is best treated by which of the following antibiotics:

• A. Cefazolin• B. Ceftriaxone• C. Bactrim• D. Ampicillin• Ampicillin was specifically designed to treat enterococcus,

although this will not pick up VRE• 1st, 2nd, 3rd generation cephalosporins and Bactrim does not

cover enterococci

• Sludging in the gallbladder and cholestatic jaundice is characteristic of which of the following antibiotics:

• A. Quinolones• B. Bactrim• C. Erythromycin• D. Ceftriaxone

• Sludging in the gallbladder and cholestatic jaundice is characteristic of which of the following antibiotics:

• A. Quinolones• B. Bactrim• C. Erythromycin• D. Ceftriaxone• Sludging in the gallbladder and cholestatic jaundice are

complications of ceftriaxone

• Match each immunoglobulin with its appropriate statement

• IgA Binds mast cells

• IgG Major antibody of the secondary immune response

• IgM Most prevalent serum immunoglobulin

• IgD May bind complement

• IgE Found particularly in secretions

Function unknown

Mediates type I hypersensitivity reactions

• Which of the following statements regarding phagocytosis are true?

• A. Neutrophils are the major phagocytic cell w/in tissue

• B. Lysosomal granules require oxygen to destroy foreign particles

• C. Chronic granulomatous disease results from a flaw in production of superoxide anions and eventually hydrogen peroxide in neutrophils

• D. Once a monocyte migrates to tissue to become a macrophage it loses all function except phagocytosis

• Which of the following statements regarding phagocytosis are true?

• A. Neutrophils are the major phagocytic cell w/in tissueTRUE

• B. Lysosomal granules require oxygen to destroy foreign particles

• C. Chronic granulomatous disease results from a flaw in production of superoxide anions and eventually hydrogen peroxide in neutrophils

• D. Once a monocyte migrates to tissue to become a macrophage it loses all function except phagocytosis

• Which of the following statements regarding phagocytosis are true?

• A. Neutrophils are the major phagocytic cell w/in tissueTRUE

• B. Lysosomal granules require oxygen to destroy foreign particles FALSE

• C. Chronic granulomatous disease results from a flaw in production of superoxide anions and eventually hydrogen peroxide in neutrophils

• D. Once a monocyte migrates to tissue to become a macrophage it loses all function except phagocytosis

• Which of the following statements regarding phagocytosis are true?

• A. Neutrophils are the major phagocytic cell w/in tissueTRUE

• B. Lysosomal granules require oxygen to destroy foreign particles FALSE

• C. Chronic granulomatous disease results from a flaw in production of superoxide anions and eventually hydrogen peroxide in neutrophils

• TRUE• D. Once a monocyte migrates to tissue to become a

macrophage it loses all function except phagocytosis

• Which of the following statements regarding phagocytosis are true?

• A. Neutrophils are the major phagocytic cell w/in tissueTRUE

• B. Lysosomal granules require oxygen to destroy foreign particles FALSE

• C. Chronic granulomatous disease results from a flaw in production of superoxide anions and eventually hydrogen peroxide in neutrophils

• TRUE• D. Once a monocyte migrates to tissue to become a

macrophage it loses all function except phagocytosisFALSE

• 2 groups of phagocytic cells: mononuclear and polymorphonuclear

• Neutrophils are polymorphonuclear and are the major phagocytic cell within the tissue

• Lysosomes destroy foreign particles w/ oxygen dependent and oxygen independent mechanisms

• In granulomatous disease there is a flaw in the production of superoxide anions and hydrogen peroxide

• Macrophages break down and process antigen to T/B lymphocytes, secrete factors to facilitate clonal expansion, produce cytokines

• Which of the following statements is false?• A. NK cells are large granular lymphocytes that do not

express the T- or B- phenotype• B. NK cells require previous exposure to antigen to

express cytotoxicity• C. NK activity is not restricted by the MHC• D. Interferon augments the activity of NK cells and

macrophages

• Which of the following statements is false?• A. NK cells are large granular lymphocytes that do not

express the T- or B- phenotype• B. NK cells require previous exposure to antigen to

express cytotoxicity• C. NK activity is not restricted by the MHC• D. Interferon augments the activity of NK cells and

macrophages• NK cells are large granular lymphocytes that do not

express T/B phenotypes, do not need previous exposure to mediate cytotoxicity to various targets, not restricted by MHC, and their activity is increased by interferon

Endocarditis prophylaxis is recommended for which of the following patients?

A. A pt. w/ mitral valve prolapse w/o murmur undergoing rigid bronchoscopy

B. A pt. w/ a h/o rheumatic fever w/ normal cardiac valves undergoing prostatic Bx

C. A pt. w/ a prosthetic aortic valve undergoing ERCP for biliary obsruction

D. A pt. w/ severe hypertrophic cardiomyopathy undergoing tympanostomy tube placement

E. A pt. Previously treated for streptococcal endocarditis undergoing tonsillectomy

Endocarditis prophylaxis is recommended for which of the following patients?

A. A pt. w/ mitral valve prolapse w/o murmur undergoing rigid bronchoscopy

B. A pt. w/ a h/o rheumatic fever w/ normal cardiac valves undergoing prostatic Bx

C. A pt. w/ a prosthetic aortic valve undergoing ERCP for biliary obsruction

D. A pt. w/ severe hypertrophic cardiomyopathy undergoing tympanostomy tube placement

E. A pt. Previously treated for streptococcal endocarditis undergoing tonsillectomy

The overall risk of endocarditis is determined by type of cardiac lesion and type of procedure known to be associated w/ significant bacteremia

Individuals at highest risk are those w/ prosthetic heart valves, previous h/o endocarditis, or complex cyanotic heart disease

Moderate risk includes hypertrophic cardiomyopathy, mitral valve prolapse w/ mitral insufficiency, and valvular disease from rheumatic fever

Pts. at moderate to high risk undergoing bacteremia producing procedures (ERCP, sclerotherapy for esophageal varices, esophageal dilatation, tonsillectomy, bronchoscopy w/ rigid scope, prostate surgery, cystoscopy) probably benefit from abx prophylaxis

Abx not indicated for endotracheal intubation, typanostomy tubes, or urethral catheterization

• Which of the following statements regarding interleukins is/are true?

• A. All interleukins will only up-regulate the immune system

• B. Interleukin-8 (IL-8) is a neutrophil chemotactic factor

• C. Interleukins are produced only by leukocytes• D. Interleukin-3(IL-3) functions as a general hematopoietic growth factor

• Which of the following statements regarding interleukins is/are true?• A. All interleukins will only up-regulate the immune system• B. Interleukin-8 (IL-8) is a neutrophil chemotactic factor• C. Interleukins are produced only by leukocytes• D. Interleukin-3(IL-3) functions as a general hematopoietic growth factor • Interleukins up and down regulate the immune system• IL 3 is a hematopoietic grwoth factor• IL 4 (macrophage cytokine secretion), IL 6 (TNF), IL 10

(monocyte/macrophage) have inhibitory functions• IL 8 attracts neutrophils to the site of inflammation• IL made by macrocytes/monophages, T/B lymphocytes, mast cells,

thymus/bonemarrow, fibroblasts, epithelial cells, and endothelial cells•

• Match each type of hypersensitivity reaction with the appropriate item

• Type I ABO incompatibility• Type II Contact Dermatitis• Type III IgE bound to mast cells and

basophils• Type IV Serum Sickness• Anaphylaxis• IgG or IgM antibody

reaction with cell bound antigen

• Tuberculin skin test

• Type I (immediate hypersensitivity) initiated by antigens that react with IgE. Binding of antigen to IgE and to mast cells/basophils causes release of histamine, slow reacting substance of anaphylaxis, serotonin, prostaglandins, and bradykinin

• Type II (cytotoxic reaction) result from reaction of IgG or IgM antibodies to cell bound antigen. Examples include Rh/ABO incompatibility, myasthenia gravis, Graves disease, and ITP

• Type III (immune complex mediated) deposition of antibody-antigen complex from circulation. Examples include serum sickness, Rheumatoid arthritis, and SLE

• Type IV (delayed type hypersensitivity) results from antigen stimulation of previously sensitized T cells (primarily CD4+). Clinical examples include TB skin test and contact dermatitis.

• Pt. w/ recurrent duodenal ulcer presents w/ recurrent abdominal pain for the last 2 years. 15 months ago, an upper endoscopy showed a duodenal ulcer. He was treated with pepcid and his condition improved, but his symptoms recurred. Before considering surgery, an upper endoscopy was repeated and a CLO test result was positive. He was then treated w/ abx and PPI for 2 weeks. Which of the following tests to assess eradication of H. pylori should be performed after treatment?

• A. Urea breath test

• B. CLO test

• C. Biopsy and culture

• D. Serum antibody (by ELISA)

• E. Stool antibody test

• Pt. w/ recurrent duodenal ulcer presents w/ recurrent abdominal pain for the last 2 years. 15 months ago, an upper endoscopy showed a duodenal ulcer. He was treated with pepcid and his condition improved, but his symptoms recurred. Before considering surgery, an upper endoscopy was repeated and a CLO test result was positive. He was then treated w/ abx and PPI for 2 weeks. Which of the following tests to assess eradication of H. pylori should be performed after treatment?

• A. Urea breath test

• B. CLO test

• C. Biopsy and culture

• D. Serum antibody (by ELISA)

• E. Stool antibody test

• Surgery is indicated in the treatment of peptic ulcers for intractable hemorrhage, perforation, and obstruction, failure of medical management

• Length of treatment varies b/t 2-4 weeks (amoxicillin, clarithromycin, flagyl, PPI, bismuth)

• Bx and CLO test require endoscopy• The serologic test for H. pylori is of limited value in

determining the success of therapy (may remain + after successful treatment)

• No stool antibody test (only antigen)

Which of the following statements regarding the collection of blood cultures is true?

A. Optimal timing for drawing a blood culture is approximately 1 hr b/f onset of fever

B. Blood collected via intravascular devices for culture should be paired w/ blood obtained by peripheral venipuncture

C. At least two sets of blood cultures should be obtained for any pt. w/ suspected bacteremia

D. A minimum of 10 cc of blood should be collected for each set of cultures

E. All are correct

Which of the following statements regarding the collection of blood cultures is true?

A. Optimal timing for drawing a blood culture is approximately 1 hr b/f onset of fever

B. Blood collected via intravascular devices for culture should be paired w/ blood obtained by peripheral venipuncture

C. At least two sets of blood cultures should be obtained for any pt. w/ suspected bacteremia

D. A minimum of 10 cc of blood should be collected for each set of cultures

E. All are correct

Early studies demonstrated that rigors and fever often follow bacteremia by 30-90 minutes

Good data documents that 2 or 3 sets of blood cultures containing at least 10 mL of blood per set demonstrates most episodes of bacteremia/fungemia

CVC blood draws should be paired w/ peripheral blood draw to aid in the interpretation of a positive test result

Which of the following statements regarding methicillin-resistant S. aureus is/are true?

A. MRSA is a common nosocomial pathogen, but it can also be detected in the community

B. The treatment of choice is vancomycin

C. MRSA is more virulent than methicillin-sensitive S. aureus

D. Hospitalized pts. Colonized w/ MRSA require contact isolation

E. Treatment of surgical pts. W/ intranasal mupirocin decreases wound infection rates due to this bacteria

Which of the following statements regarding methicillin-resistant S. aureus is/are true?

A. MRSA is a common nosocomial pathogen, but it can also be detected in the community

B. The treatment of choice is vancomycin

C. MRSA is more virulent than methicillin-sensitive S. aureus

D. Hospitalized pts. Colonized w/ MRSA require contact isolation

E. Treatment of surgical pts. W/ intranasal mupirocin decreases wound infection rates due to this bacteria

Carriage of MRSA into the community has increased

Vancomycin (treatment of choice) or linezolid can be used to treat MRSA

Some studies suggest that there is a significant increase in mortality from infections caused by MRSA vs. MSSA, but increased death rate most likely due to comorbidities and not differences in virulence

Pts. colonized w/ MRSA require contact isolation to avoid spread of bacteria to other pts.

Intranasal mupirocin does not significantly reduce S. aureus SSI but does significantly reduce rate of all nosocomial S. aureus infections amoung pts. who are S. aureus carriers

Which of the following statements regarding tetanus prophylaxis is/are true?

A. Pt. w/ a minor clean wound. His second tetanus shot was 4 yrs. ago. He requires a dose of tetanus toxoid. Antitetanus immunoglobulin is not required.

B. Pt. who has never received tetanus vaccine has a minor clean wound. He requires both toxoid and antitetanus immunoglobulin

C. Pt. who completed 3 tetanus shots when he was a child, but has not had a booster in 20 yrs. has a dirty wound. He is immune and does not require toxoid or immunoglobulin

D. Pt. / a dirty wound who does not remember when and how many tetanus shots he received in the past. He requires a toxoid dose and antitetanus immunoglobulin

Which of the following statements regarding tetanus prophylaxis is/are true?

A. Pt. w/ a minor clean wound. His second tetanus shot was 4 yrs. ago. He requires a dose of tetanus toxoid. Antitetanus immunoglobulin is not required.

B. Pt. who has never received tetanus vaccine has a minor clean wound. He requires both toxoid and antitetanus immunoglobulin

C. Pt. who completed 3 tetanus shots when he was a child, but has not had a booster in 20 yrs. has a dirty wound. He is immune and does not require toxoid or immunoglobulin

D. Pt. / a dirty wound who does not remember when and how many tetanus shots he received in the past. He requires a toxoid dose and antitetanus immunoglobulin

The majority of tetanus cases occur in older adults (age>60 yrs) who have waning immunity

Tetanus toxoid and immunoglobulin are indicated for pts. w/ dirty wounds who have received < 3 doses of toxoid in the past or whose immunization status is unknown

Only toxoid is indicated for pts. w/ dirty wounds who have received 3 doses of toxoid > 10 yrs. ago and have not had a booster w/in 5 yrs. of the injury

Pts. w/ clean minor wounds require toxoid if they have received <3 doses of toxoid less than 10 years ago and have not received a booster or the pts. immune status is unknown

Match each agent w/ 1 or more mechanisms of antimicrobial action

• Carbapenems• Aminoglycosides• Quinolones• Cephalosporins• Vancomycin

• Impairment of bacterial DNA synthesis

• Inhibition of cell wall synthesis• Disruption of ribosomal protein

synthesis• Disruption of cell wall cation

homeostasis

Carbapenems, aminoglycosides, quinolones, cephalosporins, and vancomycin are bacteriocidal; bacteriostatic agents include tetracyclines, chloramphenicol, erythromycin, clindamycin, and linezolid

Carbapenems and cephalosporins are B-lactam abx and interfere w/ enzymes w/in bacterial cytoplasmic membrane responsible for peptide cross linking which interferes w/ cell wall synthesis, eventually resulting in cell lysis

Vancomycin is a glycopeptide that also inhibits bacterial cell wall synthesis and assembly by complexing to cell wall precursors, preventing elongation and cross-linkage, making the cell susceptible to lysis (limited to gram +)

Aminoglycosides bind irreversibly to 30S bacterial ribosome and interfere w/ protein synthesis; unlike other abx that inhibit protein synthesis aminoglycosides are bacteriocidal b/c they have a disruptive effect of calcium and magnesium homeostasis w/in the cell wall

Quinolones inhibit topoisomerase II (DNA gyrase) and topoisomerase IV, impairing DNA synthesis in bacteria

For which of the following are perioperative antibiotics indicated?

A. Perforated appendix

B. Open fracture of the humerus

C. Mastectomy

D. Traumatic colon perforation

E. Elective cholecystectomy

For which of the following are perioperative antibiotics indicated?

A. Perforated appendix

B. Open fracture of the humerus

C. Mastectomy

D. Traumatic colon perforation

E. Elective cholecystectomy

• Surgical wounds can be classified according to the risk of infection• Clean wounds are defined as non traumatic in origin, no evidence of

inflammation encountered during surgery, and no break in surgical technique occur, and no breach of respiratory, alimentary, genitourinary tracts (Mastectomy); generally no antibiotic prophylaxis needed

• A clean contaminated wound is a nontraumatic wound in which a minor break in surgical technique occurs or in which the respiratory, GI, or GU tract has been entered w/ significant spillage

• Contaminated wounds include traumatic wounds (open fx) and wounds from operations involving a major break in surgical technique (gross spillage from GI tract/entrance into biliary or GU tract in presence of infection)

• Dirty: old traumatic wounds w/ devitalized tissue, clinical infection (perforated appendix)

Which of the following clinical situations or lab results require systemic antifungal therapy?

A. A single + blood culture result obtained from an indwelling venous catheter

B. Candida endopthalmitis

C. Oral candidiasis

D. Candida isolated from a drain culture in a pt. who recently underwent surgery for colon perforation

E. None of the above

Which of the following clinical situations or lab results require systemic antifungal therapy?

A. A single + blood culture result obtained from an indwelling venous catheter

B. Candida endopthalmitis

C. Oral candidiasis

D. Candida isolated from a drain culture in a pt. who recently underwent surgery for colon perforation

E. None of the above

• Candidemia is associated w/ significant morbidity (endocarditis, septic arthritis, opthalmitis) and mortality (40%)

• All pts. w/ at least 1 blood culture for Candida should be treated w/ an antifungal agent

• Amphotericin B or fluconazole appear to have similar efficacy in the treatment of candidemia

• Voriconazole and caspofungin are new antifungals also effective against Candida, but also Candida krusei or glabrata

• Candida from a surgical drain most likely represents colonization and does not require systemic antifungal therapy

• Mucocutaneous candidiasis can be treated w/ local nystatin or clotrimazole

Which of the following statements is/are correct regarding spontaneous bacterial peritonitis (primary peritonitis) in a cirrhotic patient?

A. Infection is usually polymicrobial

B. Ascitic fluid culture results are always positive

C. The most likely pathogenic mechanism is translocation from the gut

D. Five days of antibiotic treatment may be adequate

E. Infection related mortality has declined to 10%

Which of the following statements is/are correct regarding spontaneous bacterial peritonitis (primary peritonitis) in a cirrhotic patient?

A. Infection is usually polymicrobial

B. Ascitic fluid culture results are always positive

C. The most likely pathogenic mechanism is translocation from the gut

D. Five days of antibiotic treatment may be adequate

E. Infection related mortality has declined to 10%

• SBP is a monomicrobial infection• Enteric gram – rods account for 60-70% episodes• E. coli most frequent followed by Klebsiella pneumoniae• Ascitic fluid culture results are negative in many cases, but innoculation

of blood culture bottles at bedside yields bacterial growth ~80% cases• SBP most likely develops from combination of prolonged bacteremia

secondary to abnormal host defense, intrahepatic shunting, and impaired bacteriocidal activity of asicitic fluid (transmural migration/transfallopian spread may also occur)

• Third generation cephalosporin (cefotaxime/ceftriaxone) for 2 weeks suggested (but 5 days may have similar efficacy)

• Infection related mortality ~10% (in hospital mortality 40%)

Which of the following pts. w/ cirrhosis benefit from prophylactic abx to decrease risk of SBP?

A. Pts. awaiting liver transplantation

B. Pts. hospitalized w/ acute GI bleeding

C. Pts. w/ ascitic fluid protein levels < 1g/100 mL

D. Pts. who have recovered from a previous episode of SBP

E. All of the above

Which of the following pts. w/ cirrhosis benefit from prophylactic abx to decrease risk of SBP?

A. Pts. awaiting liver transplantation

B. Pts. hospitalized w/ acute GI bleeding

C. Pts. w/ ascitic fluid protein levels < 1g/100 mL

D. Pts. who have recovered from a previous episode of SBP

E. All of the above

• Randomized trials have shown that prohpylaxis w/ oral norfloxacin 400 mg/day or Bactrim 5 times/wk decreases the risk of recurrent SBP from 68% to 20% (overall mortality unchanged)

• Pts. hospitalized awaiting liver transplant likely have one of the risk factors for SBP

• Pts. who have recovered from a previous epsiode of SBP need prophylaxis

• ~30-40% of pts. w/ cirrhosis hospitalized for GI bleeding develop infection during hospitalization

• The risk of SBP increases 10X with an ascitic fluid concentration <1g/100 mL

Which of the following is/are important risk factors for the transmission of HIV to the surgeon after percutaneous injury

A. Source pt. has advanced HIV infection w/ a CD4 T-cell count of <50 cells/mm3

B. Surgeon sustains deep puncture injury

C. Visible blood was present on sharp object causing the injury

D. Injury from a device that had entered a blood vessel of the source pt. b/f injury

E. All of the above

Which of the following is/are important risk factors for the transmission of HIV to the surgeon after percutaneous injury

A. Source pt. has advanced HIV infection w/ a CD4 T-cell count of <50 cells/mm3

B. Surgeon sustains deep puncture injury

C. Visible blood was present on sharp object causing the injury

D. Injury from a device that had entered a blood vessel of the source pt. b/f injury

E. All of the above

• The risk of HIV transmission after percutaneous exposure to HIV infected blood is ~0.3%

• The risk is influenced by several factors: depth of injury, presence of indiluted blood on the device causing injury, exposure to blood from pts. In terminal stages of AIDS

• No prospective study demonstrating benefit from postexposure prophylaxis w/ AZT, but retrospective case control studies suggest in people who receive AZT prophylaxis after exposure, the odds of HIV infection were reduced by 80%

• Postexposure prophylaxis now includes at least 2 antiretroviral agents should be started w/in 72 hrs for high risk injuries

A surgical resident sustains a needle stick w/ a hollow bore needle contaminated w/ the blood of a pt. who is hepatitis B antigen positive. The resident completed a series of 3 hepatitis B vaccines 1 yr ago, but his antibody response was not checked. Which of the following statements describes the management of this case?

A. Nothing to do b/c source does not have active Hepatitis B infection

B. The resident needs a booster of Hep B vaccine

C. The resident should receive Hep B immunoglobulin immediately

D. The resident should receive Hep B immunoglobulin and Hep B vaccine booster immediately

E. The resident needs to be tested for anti-Hep B antibody immediately. If negative then give Hep B immunoglobulin and Hep B vaccine booster.

A surgical resident sustains a needle stick w/ a hollow bore needle contaminated w/ the blood of a pt. who is hepatitis B antigen positive. The resident completed a series of 3 hepatitis B vaccines 1 yr ago, but his antibody response was not checked. Which of the following statements describes the management of this case?

A. Nothing to do b/c source does not have active Hepatitis B infection

B. The resident needs a booster of Hep B vaccine

C. The resident should receive Hep B immunoglobulin immediately

D. The resident should receive Hep B immunoglobulin and Hep B vaccine booster immediately

E. The resident needs to be tested for anti-Hep B antibody immediately. If negative then give Hep B immunoglobulin and Hep B vaccine booster.

• HCWs who sustain injuries from needles contaminated w/ Hep B containing blood have arisk as high as 62% of developing serologic evidence of Hep B infection

• The source pt. is Hep B antigen positive which is an indication of active Hep B infection

• The resident has been vaccinated but his immune status is unknown

• If the resident is anti-Hep B antibody positive nothing has to be done

• If he is negative HBIG and Hep B vaccine booster should be given

• If he was never vaccinated he should be given HBIG and begin Hep B vaccination series

THE END…THE END…