Sepsis without Focus
Presentation: Ri 侯德斌
Pathogenesis
E.coli Klbesiella Enterobacter Pseudomonas, Serratia Staphylcoccus Toxin mediated: Staphylcoccal or Streptococcal toxic sho
ck, C. difficile,C. sordellii S. pneumoniae N. meningitis Candida species Other causes (less common): Salmonella enteritidis , S. typhi , Plasmodium falciparum , Listeria monocytogenes
Clinical symptom
Classic signs sepsis: fever, chills and hypotension
SIRS:
1) fever (T>38°C) or hypothermia (T<36°C)
2) tachycardia (HR>90), tachypnea (RR>20)
3) leukocytosis (WBC>12,000 or differential w/ >10% bands)
Sepsis
Definition: SIRS + infection (e.g., positive blood culture).
Severe sepsis: sepsis + organ failure, decreased perfusion (lactic acidosis, oliguria, altered mental status) or low BP
Septic shock: hypotension despite fluids + lactic acidosis, oliguria, altered mental status, despite adequate fluid resuscitation.
Special populations and clues
Neonatal (< 1 week): Group B streptococci, E. coli
HIV with CD4< 50 ~100: CMV, TB,Cryptococcus Injection drug users: S. aureus, esp. MRSA Splenectomized pts: Streptococcus pneumoniae,
Haemophilus influenzae, Neisseria meningitidis, Capnocytophaga canimorsus
Neutropenic: GNB, Aspergillus Traveler: malaria, salmonellosis
Special populations and clues
Healthy young adult: Toxic shock syndromes (S. aureus or group A strep),
N. meningitidis, Rocky Mt Spotted fever, bioterrorism ( anthrax, plague, etc),
Ecthyma gangrenosum-- Pseudomonas aeruginosa
petechiae or purpura-- Neisseria meningitidis or Rickettsial infection
Treatment
Empiric: piperacillin-tazobactam 3.375-4.5g IV q6h + vancomycin 15mg/kg q12h +/- tobramycin 5-7mg/kg/d.
Alt: aminoglycoside, e.g., gentamicin or tobramycin 5mg/kg/d or amikacin 15mg/kg/d all IV
Alt: beta-lactam (IV, choose one) : cefotaxime 2g q6h, ceftriaxone 1g q12h, cefepime 2g q12h, ceftazidime 2g q8h, imipenem 0.5-1g q6h, meropenem 1g q8h or piperacillin-tazobactam 3.375g q6h
Treatment
Vancomycin should be dosed 15mg/kg q12h if normal renal function.
Neutropenia: ceftazidime, imipenem or cefepime +/- aminoglycoside.
Intra-abdominal sepsis: ticarcillin-clavulanate, piperacillin-tazobactam, imipenem, all +/- aminoglycoside.
Tissue perfusion maneuvers
Resuscitation: IV fluids Vasopressors Inotropic agent Steroids Blood: transfuse if Hgb <7 g/dL, target goa
l Hgb >7-9 g/dL Activated protein C
Suspected source
Respiratory: Lower respiratory tract infection, such as
mycoplasma and legionella Abdominal : If ultrasound has yielded nothing, the com
puterized tomography (CT) of the abdomen and pelvis is necessary
Urinary tract : urinary cultures
Suspected source
Sinuses : long term nasogastric tubes, Plain x-rays and CT
will demonstrate fluid levels in the sinuses if they are occluded / infected.
Heart: endocarditis is one of the most malignant causes
of systemic sepsis Central nervous system : a brain abscess or meningitis, Tools: brain CT o
r CSF
What else source?
Examine the mouth for dental abscesses; the prostate; the ischeo-rectal area; intravenous catheter; subcutaneous pus collection; bone marrow
Infection of central venous catheter
Exit site infection:
the presence of erythema, tenderness, induration and purulence
Blood stream infection
Defination
Catheter colonisation:
Significant growth of a microorganism in a culture of the catheter tip, subcutaneous catheter segment, or catheter hub.
Catheter related blood stream infection
Catheter related blood stream infection
Bacteremia or fungemia in a patient who has an intravascular device and > =1 positive result of culture of blood samples obtained from the peripheral vein.
Clinical manifestations of infection (e.g., fever, chills, and/or hypotension).
No apparent source for bloodstream infection (with the exception of the catheter).
Catheter related blood stream infection
One of the following should be present: A positive result of semiquantitative ( > =15 cfu per cat
heter segment) or quantitative ( > =100 cfu per catheter segment) catheter culture, whereby the same organism (species and antibiogram) is isolated from a catheter segment and a peripheral blood sample
Simultaneous quantitative cultures of blood samples with a ratio of > =5 : 1 (CVC vs. peripheral)
Differential time to positivity (i.e., a positive result of culture from a CVC is obtained at least 2 hours earlier than is a positive result of culture from peripheral blood)
Pathogen factor
The Biofilm Factor:
Helps these organisms adhere to and survive on the surfaces of foreign bodies
The Thrombin Sheath Factor:
Rich in host-derived proteins, providing adhesion site, like coagulase-negative staphylococci bind to fibronectin, while C
albicans binds to fibrin
PREVENTION
Silver Ions: for short term < 10 days Antimicrobial/Anticoagulant flush Solution: Vancom
ycin hydrochloride,
in combination with heparin sodium or minocycline hydrochloride combined with EDTA
Antimicrobial Impregnation:
combination of either chlorhexidine gluconate and silver sulfadiazine or minocycline and rifampin.
MANAGEMENT
MANAGEMENT
Coagulase-negative staphylococci–5 to 10
daysFor uncomplicated S aureus–related CRB
SIs, it should range from 10 to 14 daysPatients with deep-seated infections (endo
carditis or septic thrombosis) should receive 4 to 6 weeks of treatment
Candidemia
C albicans or C parapsilosis can be treated with fluconazole for at least 14 days after catheter removal
Candida krusei, should be treated with high-dose amphotericin B, 1.0 mg/kg per
day
A study about haematology patients
Table I. Underlying haematological diagnosis in the 87 patients included
Result
Microbiological characteristics of 103 episodes of catheter-related bloodstream infection
Conservatively V.S. central venous catheter removal
Discussion
Hazardous in the presence of characteristic thrombocytopenia?
Difficult patientStudies in this area are generally small,
retrospective, and confined to specific populations
Pathogens vary dramatically between different groups
Discussion
Inappropriateness of applying research findings in one population to practice involving another.
Cancer patient populations have successful conservative management of CR-BSI ranging between 46% and 94%
In dialysis patients typically only 25–37%
Conclusion
Overview all suspected sources Notice the special clue, like Injection drug
users, neonatal, neutropenic patients, etc.Artifact foreign body, like CVC(CVP)Pathogens vary dramatically between diff
erent groups, this fact affects our management decision.
References
Journal of Hospital Infection: Volume 57, Issue 4, August 2004, Pages 325-331
ARCH INTERN MED/VOL 162, APR 22, 2002. Issam I. Raad, MD; Hend A. Hanna, MD, MPH
Guidelines for the management of intravascular catheter-related infections. Clin Infect Dis 2001;32:1249-72.
Sepsis - Unknown Source: John G. Bartlett, M.D. 12-10-2007 N Engl J Med 2006;355:1699-713 Copyright c 2006 Massachusetts Medic
al Society. http://www.ccmtutorials.com/index.htm Pat Neligan December 2006 Univ
ersity of Pennsylvania
Thanks for your attention!