PPT

1. BLOODSTREAM INFECTIONS& INFECTIONS
CAUSING ANAEMIA
DR. D. Therese Mary
Associate Professor of Microbiology
GKMC

2. CONTENTS
 INTRODUCTION
 TERMINOLOGIES
 TYPES OF BACTEREMIA
 ETIOLOGIES
 TYPES OF BLOODSTREAM INFECTIONS
 CLINICAL MANIFESTATIONS
 LABORATORY DIAGNOSIS
 TREATMENT
 FEVER OF UNKNOWN ORIGIN (FUO)
 INFECTIONS CAUSING ANAEMIA

3. INTRODUCTION
Presence of
microorganisms in
blood
One of the most
serious among
infectious diseases
Threat to every
organ in the body

4. TERMINOLOGIES
Bacteremia
Septicemia
Viremia
Parasitemia
Fungemia

5. TYPES OF BACTEREMIA
Transient Bacteremia
Spontaneous or with minor events like brushing teeth, chewing food,
instrumentation of contaminated mucosal site , surgery involving non-
sterile
Intermittent Bacteremia
Intermittent release of bacteria from sequestrated focus of
infection(undrained abscess),early course of meningitis, pneumonia
,septic arthritis and osteomyelitis
Continuous Bacteremia
Organisms are released into the bloodstream at a constant rate
Early stage of enteric fever, brucellosis, leptospirosis

6. ETIOLOGY
BACTERIAL
PRIMARY ; typhoidal salmonellae, brucellae, (Leptospira and
Borrelia)
HACEK Group, S.viridans, Rickettsiae
SECONDARY
 GPC; staphylococci, beta hemolytic streptococci, enterococci and
pneumococci
 GNC ; meningococci
 GNB ; E.coli, Klebsiella, Enterobacter, non –fermenters, Haemophilus,
 GPB ; B.anthracis, Listeria
 Anaerobes ; bacteroides

7. ETIOLOGY
 VIRAL
HIV, Dengue, Chikungunya, Ebola, Marburg ,Lassa fever,
Epstein-Barr virus, CMV
 PARASITIC
Plasmodium, Babesia, Toxoplasma gondii, Leishmania,
Trypanosoma, filarial parasites
 FUNGAL
Candida, Histoplasma, Blastomyces, Coccidioides,
Paracoccidioides

8. TYPES OF BLOODSTREAM INFECTION
 INTRAVASCULAR
&EXTRAVASCULAR
Predisposing factors
 Immunosuppression
 Broad spectrum antibiotics
 Invasive procedures
 Prolonged survival of debilitated
patients
 Intravascular
Originate within the cardiovascular
system(endocarditis, myocarditis, pericarditis) and
infection of blood vessels
 Extravascular
Genitourinary tract 25%,
Respiratory 20
Abscesses 10%,
SSI 5%,
Biliary tract 5%,
uncertain 25%

9. BACTERIA CAUSING EXTRAVASCULAR
INFECTIONS& PORTAL OF ENTRY
BACTERIA PORTAL OF ENTRY/SOURCE
E.Coli ,Klebsiella ,Enterobacter, Proteus,
Pseudomonas
Urinary tract, rarely intestine
Haemophilus influenza b Meninges, epiglottis,lungs
Pneumococcus Meninges ,lungs
Brucella Reticuloendothelial system(RES)
S,typhi Small intestine, lymph nodes,RES
Listeria Intestine, meninges
S.aureus,CoNS Surgical site infections

10. CLINICAL MANIFESTATIONS
A)Bacteremia
B)Sepsis-Life threatening organ dysfunction caused
by a dysregulated host response to infection.
Mortality 10%
 Fever or Hypothermia with or without rigors
 Hyperventillation, respiratory alkalosis
 Skin lesions,altered mental status, diarrhoea
 SOFA &Quick SOFA score(Sepsis related organ
failure assessment)
 SOFA depends upon 6 parameters
1.Respiratory system-PaO2/FiO2
2.Coagulation system-Platelet count
3.Liver-Serum bilirubin
4.CVS-Mean arterial pressure
5.CNS-Glasscow coma scale
6.Renal- creatinine and urine output
Organ dysfunction-Acute change in the total
SOFA score ≥2 points following infection
qSOFA criteria-Bedside
RR ≥ 22/mt
Altered mentation
Systolic Bp ≤ 100mm of Hg

12. CLINICAL MANIFESTATIONS
C)Septic shock
Persisting hypotension requiring
vasopressors to maintain MAP ≥65
mm of Hg
Serum lactate more than 18mgm/dl
despite adequate volume
resuscitation.
Mortality more than 40%

13. SEPTIC SHOCK

14. LABORATORY DIAGNOSIS
 Isolation of organism from blood by blood culture
Specimen collection
 Site 2
 Skin decontamination-2 step procedure
 Timing
 Blood volume-8 to 10 ml adult,1 to 3 ml pediatric
 Number of blood culture-2 to 3 blood culture sets
 Dispensing
 Transport

15. CULTURE
Conventional
 Monophasic(50-100ml BHI broth)
 Biphasic(Castaneda’s BHI agar slope
& BHI broth 50ml)
 Dilution 1:5
 SPS(sodium polyanethol sulfonate)
 Incubation -37 degree Celsius for 7
days
 Repeat subcultures(MacConkey
agar,BAP)

16. CULTURE-AUTOMATED
 BACTEC & BacT/ALERT
 Faster isolation & increased
sensitivity
 Identification conventional or
MALDI-TOF or VITEK

17. OTHER INVESTIGATIONS
Complete blood count
C-reactive protein(CRP)
Procalcitonin
Biochemical markers-LDH
Cytokine assay-IL-6

18. AST AND TREATMENT
 MIC BASED VITEK
preferred over disc
diffusion method
 Empirical- carbapenams
and vancomycin
 Definitive-based on culture
sensitivity report
 Supportive measures

19. FEVER OF UNKNOWN ORIGIN(FUO)
 Current definition
 Fever more than ≥ 101 degree on
atleast 2 occasions, duration≥ 3 weeks,
no immunocompromised state
 Diagnosis remains uncertain after
thorough history-taking,physical
examination and the following
obligatory investigations:
 ESR &CRP
 Complete blood count
 Electrolytes, creatinine,total protein, ferritin
and protein electrophoresis
 Enzymes like alkaline phosphatase, alanine
aminotransferase, aspartate aminotransferase,
LDH,creatine kinase
 ANA & RF
 Urine analysis
 Blood culture(3 negative ),urine culture
 Radiology; x-ray chest, USG abdomen

20. ETIOLOGY
 INFECTIONS(36%)-Localized and systemic
 NEOPLASMS(19%)
 NON-INFECTIOUS INFLAMMATORY DISORDERS(connective tissue
disorder) 19%
 Miscellaneous causes(19%)-granulomatous disease, inherited and
metabolic disease, thermoregulatory disorders
 Undiagnosed (7%)

21. LABORATORY DIGNOSIS
 Complete history before collection of specimens
 Microscopy-malarial parasite, filarial ,L.donovani, toxoplasma
 Stool wetmount- cyst, trophozoite, ova of parasite causing FUO
 Gram stain-pus ,sputum etc.
 Ziehl-Neelsen- M.tuberculosis
 Periodic acid-Schiff(PAS)or Gomori methenamine silver (GMS)-fungal
morphology

22. SEROLOGICAL TESTS
 ELISA - Hepatitis B,C,HIV,CMV,EBV
 STANDARD AGGLUTINATION TEST(SAT)-Brucellosis
 MICROSCOPIC AGGLUTINATION TEST-Leptospirosis
 COLD AGGLUTINATION TEST -Mycoplasma
 WEIL-FELIX TEST -Ricketssial disease
 PAUL-BUNNELL TEST -Infectious mononucleosis
 WIDAL TEST -Enteric fever
 MICROIMMUNOFLUORESCENCE -Chlamydiae
 RHEUMATOID FACTOR -Rheumatoid arthritis
 ANTINUCLEAR ANTIBODY TEST -SLE

23. MOLECULAR & OTHER TESTS
 POLYMERASE CHAIN REACTION-MULTIPLEX PCR
 COMPLETE BLOOD COUNT-Neutrophilia, pyogenic infection
 ESR
 HISTOPATHOLOGICAL EXAMINATIONS OF THE BIOPSIES
 IMAGING METHODS; CT,MRI,USG
 ECG AND ECHOCARDIOGRAPHY-Rheumatic fever and
infective endocarditis

24. INFECTIONS CAUSING ANEMIA
 IRON DEFICIENCY ANEMIA
Hook worm, Trichuris, Schistosoma
 HEMOLYTIC ANEMIA
Plasmodium, Babesia, Bartonella
Clostridial sepsis, Mycoplasma, Infectious mononucleosis, Hepatitis A
 MEGALOPLASTIC ANEMIA
Diphyllobothrium latum
 APLASTIC ANEMIA
M.tuberculosis, Ricketssial infection, L.donovani, CMV,EBV, Varicella-
zoster,parvo virus B19,HIV,Human herpes virus 6,HCV,Dengue virus(rarely)

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