Infective EndocarditisInfective Endocarditis

Prof DR Asem ShehabiProf DR Asem Shehabi

Faculty of medicine, University of Faculty of medicine, University of JordanJordan

Infective endocarditis-1Infective endocarditis-1 Fever of unknown originFever of unknown origin.. Common cause of .. Common cause of

Infective Endocarditis..Inflammation of the Infective Endocarditis..Inflammation of the endocardium.. inner of the heart muscle.. associated endocardium.. inner of the heart muscle.. associated with the epithelial lining of with the epithelial lining of heartheart valves valves .. It is caused .. It is caused by a wide variety of bacteria ..rarely a fungus or virus. by a wide variety of bacteria ..rarely a fungus or virus.

Defensive immune mechanismsDefensive immune mechanisms..WBCs cannot ..WBCs cannot directly reach the valves via the bloodstream.directly reach the valves via the bloodstream.

If any organism attaches to a valve surface and If any organism attaches to a valve surface and forms forms a vegetationa vegetation, the host immune response will be , the host immune response will be inhibited. inhibited.

The lack of blood supply to the valves also has The lack of blood supply to the valves also has implications on treatment, since antimicrobial drugs implications on treatment, since antimicrobial drugs have difficulty reaching the infected valve.have difficulty reaching the infected valve.

22// The incidence of infective The incidence of infective endocarditisendocarditis in a in a

general population has been estimated general population has been estimated between between 2-6 cases per 100,000 patient/ year2-6 cases per 100,000 patient/ year,,

It is higher in patients with underlying It is higher in patients with underlying congenital & congenital & valvular heart diseasevalvular heart disease.. .. intravenous drug abuseintravenous drug abuse .. .. invasive surgery & invasive surgery & oral dental proceduresoral dental procedures. .

All invasive procedures may cause blood All invasive procedures may cause blood stream infections and result in acute or stream infections and result in acute or subacute subacute endocarditisendocarditis..

33// Historically, Historically, rheumatic disease ..Group A rheumatic disease ..Group A

Streptococci Streptococci was considered a frequent pre-was considered a frequent pre-disposing factor for disposing factor for endocarditisendocarditis. .

Prosthetic valvularProsthetic valvular heart disease accounts for heart disease accounts for about 1/3 of all cases of about 1/3 of all cases of endocarditisendocarditis, and , and occurs in 1% to 3% of patients after occurs in 1% to 3% of patients after valvular valvular heart surgery.heart surgery.

Any damage in heart valves induce formation of Any damage in heart valves induce formation of endocarditic vegetationendocarditic vegetation .. involving .. involving bacteriabacteria, , plateletsplatelets, , fibrin fibrin and few and few leucocytesleucocytes, and is , and is considered a special kind of considered a special kind of biofilmbiofilm

44// Acute endocarditisAcute endocarditis followed bacteremia..mostly followed bacteremia..mostly

S. aureus ..Bacteria cells settle on S. aureus ..Bacteria cells settle on normalnormal or or deformed heart valvesdeformed heart valves.. Multiply, Interact & .. Multiply, Interact & cause rapid destruction ..Fatal cardiac failure.. cause rapid destruction ..Fatal cardiac failure.. days-weeksdays-weeks..

Subacute endocarditisSubacute endocarditis .. often developed by .. often developed by presence presence abnormal valvesabnormal valves.. .. congenital congenital deformitiesdeformities & & rheumatic lesionsrheumatic lesions.. slowly .. .. slowly .. caused by few Gram-positive cocci.. mostly caused by few Gram-positive cocci.. mostly Strept. Viridans Strept. Viridans causing first subacute causing first subacute bacteremia..Low fever & other symptoms. bacteremia..Low fever & other symptoms.

Predisposing Factors for EndocarditisPredisposing Factors for Endocarditis Congenital heart disorders.. Prosthetic heart valves Congenital heart disorders.. Prosthetic heart valves Periodontal proceduresPeriodontal procedures Dental extractions, Dental implantsDental extractions, Dental implants Tonsillectomy , Esophageal dilationTonsillectomy , Esophageal dilation Skin infections.. Intravenous drug users Skin infections.. Intravenous drug users Cystoscopy.. Urethral dilation, Colonoscopy, Cystoscopy.. Urethral dilation, Colonoscopy, All these procedures.. associated with Commensal All these procedures.. associated with Commensal

flora.. Endogenous infections.flora.. Endogenous infections. Antibiotic Prophylaxis is recommended.Antibiotic Prophylaxis is recommended.

Microbial Causes-1Microbial Causes-1 Gram-positive cocci..Gram-positive cocci.. facultative anaerobes,.. occur as facultative anaerobes,.. occur as

chains/clusters or pairs .. chains/clusters or pairs .. Catalase+veCatalase+ve /Staphylococci group, /Staphylococci group, catalasecatalase-ve/ Streptococci & Enterococci groups.-ve/ Streptococci & Enterococci groups.

Streptococci Streptococci are subdivided into groups according their are subdivided into groups according their hemolytic reaction on blood agar in vitro & by serotypes hemolytic reaction on blood agar in vitro & by serotypes surface cell wall specific carbohydrate antigenssurface cell wall specific carbohydrate antigens. .

Viridans streptococciViridans streptococci.. Normal oral-intestinal flora.. .. Normal oral-intestinal flora.. Common causes of Common causes of dental cariesdental caries.. .. Oral abcessesOral abcesses.. do not .. do not possess a specific carbohydrate antigens.. Carry possess a specific carbohydrate antigens.. Carry certain M certain M protein types protein types

Microbial Causes-2Microbial Causes-2 Viridans streptococci GroupViridans streptococci Group.. Deposit dextran, .. Deposit dextran,

adhesins, Fibronectin-binding protein.adhesins, Fibronectin-binding protein.

Group A StreptococciGroup A Streptococci ((S. pyogenesS. pyogenes).. Repeat Sore ).. Repeat Sore throat infection.. Less skin infection.. Develop Pos-throat infection.. Less skin infection.. Develop Pos-streptococcal Diseases ..streptococcal Diseases ..Rheumatic heart diseaseRheumatic heart disease.. .. Children..observed in Jung adults. Children..observed in Jung adults.

Virulence substance M-protein (80 types) Virulence substance M-protein (80 types) ....Cell wall Cell wall antigensantigens + associated + associated M-proteinM-protein cross-react with the cross-react with the cardic muscle tissuescardic muscle tissues.. causing damage .. can be .. causing damage .. can be responsible for responsible for rheumatic myocarditisrheumatic myocarditis.. .. M-proteinM-protein Type Type Specific AntibodiesSpecific Antibodies is protecting host to some extent. is protecting host to some extent.

Group A Hemolytic Streptoccci groupGroup A Hemolytic Streptoccci group

Microbial Causes-3Microbial Causes-3

Responsible for the largest percentage of cases (30-Responsible for the largest percentage of cases (30-40%).. Certain species Viridans streptococci, like 40%).. Certain species Viridans streptococci, like S. S. mitismitis, S. , S. mutansmutans account for 10% of cases, and tend to account for 10% of cases, and tend to be be less susceptible to penicillinless susceptible to penicillin. .

Enterococcus speciesEnterococcus species ( E. fecalis, E. faecium) are ( E. fecalis, E. faecium) are responsible for up to 5-responsible for up to 5-10% of cases10% of cases; some strains ; some strains may be resistant to penicillin, and to may be resistant to penicillin, and to vancomycin.vancomycin.

The treatment of choice for infections caused The treatment of choice for infections caused by Viridans streptococci is still penicillin, and by Viridans streptococci is still penicillin, and vancomycin or teicoplaninvancomycin or teicoplanin

Streptococci-StaphyloccociStreptococci-Staphyloccoci

Microbial Causes-5Microbial Causes-5

S. aureusS. aureus is a common cause of is a common cause of endocarditisendocarditis, may , may result in a severe sepsis syndrome with a fatal result in a severe sepsis syndrome with a fatal outcome. outcome.

Metastasis staphylococci fociMetastasis staphylococci foci spread to the brain, spread to the brain, lungs, liver, and kidneys. These complications result in lungs, liver, and kidneys. These complications result in a very high mortality rate. a very high mortality rate.

Most endocarditis cases occurred within 2-month-1 Most endocarditis cases occurred within 2-month-1 year year following surgery.. year year following surgery.. contamination by skin contamination by skin bacteria. bacteria.

Infections from Infections from vascular cathetersvascular catheters & & surgical woundssurgical wounds are more frequent sources of infection. are more frequent sources of infection.

Infective agents of Native Valve Infective agents of Native Valve EndocarditisEndocarditis

OrganismsOrganismsCases %Cases %

Streptococcus viridansStreptococcus viridans 30-4030-40

Enterococcus speciesEnterococcus species 5-105-10

Other streptococci Other streptococci 10-2510-25

Staphylococcus aureusStaphylococcus aureus / / Coagulase-negative Coagulase-negative staphylococci staphylococci

10-25 / 10-25 /

1-31-3

Gram-negative bacilliGram-negative bacilli

Brucella, SalmonellaBrucella, Salmonella

2-132-13

Fungi (Candida), AspergillusFungi (Candida), Aspergillus2-42-4

OthersOthers55

Microbial Causes-6Microbial Causes-6 A group of fastidious gram-negative bacteria can A group of fastidious gram-negative bacteria can

cause endocarditis : Gram-ve cause endocarditis : Gram-ve bacteria: Brucella, bacteria: Brucella, Salmonella, Haemophilus, Cardiobacterium, Eikenella, Salmonella, Haemophilus, Cardiobacterium, Eikenella, Gram+ve ActinobacillusGram+ve Actinobacillus..

Clinically, these bacteria spp. causing Clinically, these bacteria spp. causing subacute or subacute or chronic coursechronic course, and often present with , and often present with embolic lesionsembolic lesions from large vegetations in herat valves .from large vegetations in herat valves .

Most cases of fungal endocarditis occur in patients Most cases of fungal endocarditis occur in patients who are receiving prolonged antibiotics or parenteral who are receiving prolonged antibiotics or parenteral nutrition through central vascular catheters.. Immuno-nutrition through central vascular catheters.. Immuno-compromised patients. compromised patients.

Yeast & Filamentous FungiYeast & Filamentous Fungi

The most common species is The most common species is Candida albicansCandida albicans, , followed by other followed by other Candida spp.Candida spp. ( C. glabrata, C. ( C. glabrata, C. krusei, C. tropicals)..krusei, C. tropicals)..

Common bacterial Normal flora.. Oral-intestinal-Common bacterial Normal flora.. Oral-intestinal-Urinary tract (Vagina).. Infection often followed Urinary tract (Vagina).. Infection often followed often using catheters or respiratory intubation.often using catheters or respiratory intubation.

Endocarditis due to Endocarditis due to Histoplasma capsulatumHistoplasma capsulatum or or AspergillusAspergillus species is very rare.. Immuno- species is very rare.. Immuno-supressed patients.supressed patients.

Candida albicans PseudohyphaeCandida albicans Pseudohyphae

Diagnosis &TreatmentDiagnosis &Treatment Clinical Clinical DiagnosisDiagnosis is usually suspected based upon is usually suspected based upon

the patient's history, symptoms, and findings such as the patient's history, symptoms, and findings such as a new murmur.. Fever. a new murmur.. Fever.

EchocardiogramEchocardiogram.. .. UltrasoundUltrasound study of the heart study of the heart muscle and valves may be helpful in identifying a muscle and valves may be helpful in identifying a clump of bacteria clump of bacteria on the heart valve.on the heart valve.

Suspected Endocarditis ..Collect 3 blood for culture.. Suspected Endocarditis ..Collect 3 blood for culture.. within 1-2 days.. Before treatment with antibiotics within 1-2 days.. Before treatment with antibiotics

Culture first for bacteria.. second for fungi if treatment Culture first for bacteria.. second for fungi if treatment with antibiotic failed with antibiotic failed

22// About 10-50% of patients with clinically-About 10-50% of patients with clinically-

suspected endocarditis will have negative blood suspected endocarditis will have negative blood cultures for any organism..Previous antibiotic cultures for any organism..Previous antibiotic treatment. treatment.

Select antibiotic treatment according type of Select antibiotic treatment according type of bacteria & susceptibility test.bacteria & susceptibility test.

Antibiotic therapy Antibiotic therapy must continue for at least a must continue for at least a month.. Most patients respond rapidly to month.. Most patients respond rapidly to appropriate antibiotics and becoming without a appropriate antibiotics and becoming without a fever within one week.fever within one week.