Slide 1

Slide 2 SEPTICAEMIA Dr. Urvesh V. Shah Associate Professor Editor in Chief, Dept. of Microbiology, GCSMC Journal Of GCS Medical College Medical Sciences Slide 3 Sepsis is a condition characterized by a whole-body inflammatory state (called a systemic inflammatory response syndrome or SIRS) that is triggered by an infection. The body may develop this inflammatory response by the immune system to microbes in the blood, urine, lungs, skin, or other tissues inflammatorysystemic inflammatory response syndrome infectionimmune systemmicrobes bloodurinelungsskin Slide 4 Bacteremia is the presence of viable bacteria in the bloodstreambacteria Slide 5 Septicemia is a related medical term referring to the presence of pathogenic organisms in the bloodstream, leading to sepsis is the term used when the organisms causing the sepsis are identified in the blood. Sepsis + Bacteremia Slide 6 Blood culture Diagnose: ? Bacteremia Presence of Bacteria in Blood Slide 7 Bacterial colonization Bacteremia Local Multiplication & invasion Inflammation Local pyogenic infection with SIRS Multiplication & invasion in blood SIRS Septicaemia Multiple organ invasion & SIRS Transient bacteremia & no invasion systemic infection i.e. Typhoid, Brucellosis Slide 8 Bacteremia systemic infection i.e. Typhoid, Brucellosis Slide 9 Bacterial colonization Bacteremia Local Multiplication & invasion Inflammation Local pyogenic infection with SIRS Concentration of Organisms in Bacteremia In Children: Gram Negative Bacteremia 5 to 1000 organisms / mL 75% of children have > 100 organisms / mL of blood In Adults: Streptococcus Endocarditis 1 to 30 organisms /mL Gram Negative Bacteremia < 1 to 10 organisms /mL Cop y right BD Europe Slide 17 To increase isolation rate: Volume of blood to be cultured should increase. Cockerill F R et al. Clin Infect Dis. 2004;38:1724-1730 Slide 18 Isolation of bacteria also depend upon inhibitors of bacterial growth in blood i.e. antibiotics, antibodies etc. Their activity can be reduced by diluting them So, More than one bottle can be utilized for higher volume of blood Not more than 10 ml of blood permitted in one bottle Slide 19 How many sets of blood culture Slide 20 How many sets of cultures? Rev Infect Dis.Rev Infect Dis. 1986 Sep-Oct;8(5):792-802. Blood cultures: issues and controversies. Washington JA 2ndWashington JA 2nd, Ilstrup DM.Ilstrup DM the volume of blood cultured appears to be most important. It is recommended that at least 10 ml, and preferably 20-30 ml, of blood be obtained. More than three separate blood cultures per septic episode is rarely necessary Slide 21 In pre septic conditions A case of SIRS 2 or more of following criteria Temperature > 38 or90 /m Respiratory rate: >20/m WBC: > 12,000 or 10% band cells Slide 46 Sepsis SIRS + evidence of bacterial infection Procalcitonin / CRP raised Slide 47 Illustration from Brahms Increasing concentration in the blood as sepsis goes to severe sepsis and septic shock PCT concentration g/ml Clinical Condition 0.05 10 Healthy condition Local infection Systemic bacteria infection (Sepsis ) Severe Sepsis Shock < 0.5 2.0 Kinetics of PCT in Evolving Sepsis Slide 48 Accurate Diagnosis of SEPSIS for Rapid Initiation of Antibiotics On admission Pt of SIRS *Guidelines from the German Sepsis Society Is it really sepsis? Question 2.0ng/ml Sepsis very unlikely Sepsis very likely Clinical Interpretation Other Diagnosis ? Start AB Therapy Consequence for physician Slide 49 Schuetz P, Curr Opin Crit Care, 07 Patient Admitted to the ICU With Systemic Inflammatory Response Syndrome (SIRS) Microbiological Workup Identification of Organism No Identification Exclusion of Contamination Clinical Evaluation Consider Antibiotic Therapy Depending on Clinical Setting Withhold / Stop Antibiotics 2.0 Diagnosis of Sepsis ? Evaluation of Procalcitonin Cut off Range Very Unlikely LikelyUnlikely Very Likely Slide 50 Use of a clinical PCT algorithm safely and markedly improves diagnosis and antibiotic stewardship in upper and lower LRTI Local sepsis: LRTI Guidelines: Support Diagnosis & Antibiotic Guidance Schuetz P et al, BMC HSR 07 & pro HOSP 2009 Slide 51 PCT < 0.1 ng/mL in healthy subjects blood Increases specifically when body is bacterialy challenged Rapidly increases 2-3 hours with a peak after 6-12 hrs Rapidly decreases with effective therapy with half-life time (~ 24 hr) PCT Kinetics Slide 52 Be careful Increased PCT may be due to Other infections: invasive fungal, acute P.falciparum Neonates ( up to 20 ng / ml in initial 48 hours) Severe burns, major trauma, major surgical interventions, prolonged or severe cardiogenic shock PCT may not raise in Some local infections e.g. Arhtritis, osteomilitis, endocarditis Slide 53 Conclusion Sepsis is an important cause of morbidity and mortality in the critical care unit. An average attributable mortality of 26% Clinical parameters are often not reliable predictors of bacteremia. Blood cultures remain a valuable diagnostic tool. Every effort should be made to improve the yield of this diagnostic modality, and results obtained should be interpreted in light of clinical and other laboratory data and culture reports of other speciemens. Slide 54 Conclusion Once bacteremia is identified, repeated cultures with each temperature elevation, especially in patients who are clinically unchanged, are unnecessary. Till culture reports available or culture report is negative, Antibiotic therapy should be started and modified with Procalcitonin / CRP ? level monitoring The judicious use of cultures, while paying attention to factors that improve blood culture yield and decrease contamination rates, will improve the utility of blood cultures as diagnostic tools in critically ill patients. Slide 55 Bid adieu to infection Thanks for Your Participation! Dr. Urvesh V. Shah Associate Professor Editor in Chief, Dept. of Microbiology, GCSMC Journal Of GCS Medical College Medical Sciences