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.. is caused by a wide .. is caused by a wide

variety of bacteria ..rarely a fungus or virus. variety of bacteria ..rarely a fungus or virus. Infective EndocarditisInfective Endocarditis..Commonly associated with ..Commonly associated with

FUO.. Inflammation of the endocardium.. inner of the FUO.. Inflammation of the endocardium.. inner of the heart muscle & the epithelial lining of heart muscle & the epithelial lining of heart valves.heart valves.

Any organism attaches to a valve surface and Any organism attaches to a valve surface and forms a forms a vegetationvegetation and the host immune response will be and the host immune response will be inhibited. inhibited.

Any damage in heart valves induce formation of Any damage in heart valves induce formation of endocarditic vegetation.. endocarditic vegetation.. A A Biofilm .. Biofilm .. Accumulation Accumulation BacteriaBacteria, , plateletsplatelets, , fibrin fibrin and few and few leucocytesleucocytes. .

Generally, Host defensive immune mechanisms Generally, Host defensive immune mechanisms including WBCs can’t directly reach the valves via the including WBCs can’t directly reach the valves via the bloodstream and prevent development endocarditisbloodstream and prevent development endocarditis

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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 have difficulty reaching the infected valve.infected valve.

The incidence of infective The incidence of infective endocarditisendocarditis in a general in a general healthy population has been estimated between healthy population has been estimated between 3-9 3-9 cases per 100,000 patient/ year in western countriescases per 100,000 patient/ year in western countries..

EndocarditisEndocarditis is twice as common among men, than is twice as common among men, than women. It can strike at any age, most cases occur women. It can strike at any age, most cases occur with people over the age of 50.with people over the age of 50.

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 & oral dental proceduresinvasive surgery & oral dental procedures. .

33// Historically, Historically, Rheumatic Disease Rheumatic Disease ..caused by ..caused by

Group A Streptococci Group A Streptococci was considered a was considered a frequent pre-disposing factor for frequent pre-disposing factor for endocarditis.endocarditis.

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..Occurs in ..Occurs in 1% to 3% of patients after 1% to 3% of patients after valvular heart valvular heart surgery. surgery.

All invasive procedures may cause blood All invasive procedures may cause blood stream infections and result in stream infections and result in acuteacute or or subacutesubacute endocarditis endocarditis..

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

Staphylococci (Staphylococci (S. aureusS. aureus) & streptococci (85%) ) & streptococci (85%) Bacteria cells settle on Bacteria cells settle on normalnormal or or deformed deformed heart valvesheart valves.. multiply, interact & cause rapid .. multiply, interact & cause rapid destruction ..Fatal cardiac failure.. destruction ..Fatal cardiac failure.. days-weeksdays-weeks..

Subacute endocarditis Subacute 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 group less Enteroccocus spp. Strept. Viridans group less Enteroccocus spp. causing first subacute bacteremia..Low fever & causing first subacute bacteremia..Low fever & other symptoms. other symptoms.

Predisposing Factors for EndocarditisPredisposing Factors for Endocarditis Congenital heart disorders, Prosthetic heart valvesCongenital heart disorders, Prosthetic heart valves

    Pacemaker, following pneumonia and meningitis Pacemaker, following pneumonia and meningitis Periodontal procedures/disease, Damaged gingival Periodontal procedures/disease, Damaged gingival

tissue due to plaque accumulation on teethtissue due to plaque accumulation on teeth Dental extractions, Dental implantsDental extractions, Dental implants Hemodialysis Tonsillectomy , Esophageal dilationHemodialysis Tonsillectomy , Esophageal dilation Skin infections.. Intravenous drug users Skin infections.. Intravenous drug users Cystoscopy. Colonoscopy, Urethral dilation, Cystoscopy. Colonoscopy, Urethral dilation, All these procedures.. associated with mucosal All these procedures.. associated with mucosal

commensal flora.. May cause endogenous infections.commensal flora.. May cause endogenous infections. Antibiotic Prophylaxis is recommendedAntibiotic Prophylaxis is recommended..

Microbial Causes-1Microbial Causes-1 Gram-positive cocciGram-positive cocci.... facultative anaerobes, diplococci facultative anaerobes, diplococci

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

StreptococciStreptococci subdivided into groups according their subdivided into groups according their hemolytic reaction on blood agar in vitro & by serotypes hemolytic reaction on blood agar in vitro & by serotypes according to according to 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 abscessesOral abscesses.. do not .. do not possess a specific carbohydrate antigens.. Carry certain possess a specific carbohydrate antigens.. Carry certain M M protein protein types.types.

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

adhesins, Fibronectin-binding protein..attract adhesins, Fibronectin-binding protein..attract platelets..development platelets..development Plaque.. Plaque.. GingivitisGingivitis

Responsible for the largest percentage of Responsible for the largest percentage of

Endocarditis cases (30-40%).. Certain species Endocarditis cases (30-40%).. Certain species Viridans streptococci, like Viridans streptococci, like St. mutansSt. mutans, , StSt. . mitismitis accounted for many cases, and tend to be accounted for many cases, and tend to be less less susceptible to penicillinssusceptible to penicillins. .

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 later in jung adults. Children..observed later in jung adults.

Streptococci-StaphyloccociStreptococci-Staphyloccoci

Viridans streptococci & S.aureusViridans streptococci & S.aureus

Microbial Causes-3Microbial Causes-3 Group A StreptococciGroup A Streptococci..Virulence substance ..Virulence substance M-proteinM-protein

(80 types) ..part Cell wall antigens is strongly (80 types) ..part Cell wall antigens is strongly anti-anti-phagocyticphagocytic.. cross-react with the .. cross-react with the cardic muscle cardic muscle tissuestissues.. causing damage .. responsible for .. causing damage .. responsible for rheumatic rheumatic myocarditismyocarditis.. .. M-proteinM-protein Type Specific AntibodiesType Specific Antibodies is is protecting host to some extent.protecting host to some extent.

Enterococcus Enterococcus speciesspecies ( ( E. fecalis, E. faeciumE. fecalis, E. faecium) are ) are responsible for up to 5-responsible for up to 5-10% of cases10% of cases; some strains ; some strains may be resistant to may be resistant to penicillinpenicillin,,vancomycinvancomycin..

The treatment of choice for infections caused by The treatment of choice for infections caused by Viridans streptococci is still penicillin or vancomycin / Viridans streptococci is still penicillin or vancomycin / teicoplaninteicoplanin in case of resistance. in case of resistance.

Microbial Causes-5Microbial Causes-5 S. aureusS. aureus is a common cause of is a common cause of acuteacute endocarditisendocarditis, ,

may result in a severe sepsis syndrome with a fatal may 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 following year following surgery, skin injury/ invasive dental surgery, skin injury/ invasive dental procedures and others.procedures and others.

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

10-40 / 10-40 /

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 rarely endocarditis : Gram-ve cause rarely endocarditis : Gram-ve bacteria: bacteria: Brucella, Brucella, Salmonella, Haemophilus, Cardiobacterium, Eikenella, Salmonella, Haemophilus, Cardiobacterium, Eikenella, Gram+ve ActinobacillusGram+ve Actinobacillus part of Normal oral flora part of Normal oral flora

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 lesions embolic lesions from large from large biofilm vegetations biofilm vegetations in heart valves .in heart valves .

Most cases of fungal endocarditis occur in patients Most cases of fungal endocarditis occur in patients who are receiving who are receiving prolonged antibiotics prolonged antibiotics or or intravenous intravenous nutritionnutrition through central vascular catheters.. Immuno-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 less common followed by other less common Candida spp.Candida spp. ( C. glabrata, C. krusei, C. tropicals).( C. glabrata, C. krusei, C. tropicals).

Candida part of human normal flora.. Oral-Candida part of human normal flora.. Oral-intestinal-Urinary tract (Vagina).. Infection often intestinal-Urinary tract (Vagina).. Infection often followed often using followed often using catheters or respiratory catheters or respiratory intubation.intubation.

Endocarditis due to Endocarditis due to Histoplasma capsulatumHistoplasma capsulatum / / AspergillusAspergillus species is very rare.. Immuno- species is very rare.. Immuno-suppressed patients.suppressed patients.

Candida albicans PseudohyphaeCandida albicans Pseudohyphae

Diagnosis &TreatmentDiagnosis &Treatment

Clinical DiagnosisClinical Diagnosis is usually suspected based upon is usually suspected based upon the patient's history, symptoms, and findings.. Mild the patient's history, symptoms, and findings.. Mild continues fever. continues 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 Suspected Endocarditis ..Collect 3 blood 3 blood for culture.. 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-suspected About 10-50% of patients with clinically-suspected

endocarditis will have negative blood cultures for any endocarditis will have negative blood cultures for any organism due to organism due to Previous/partial antibiotic treatment. Previous/partial antibiotic treatment.

Antibiotic treatment according to type of bacteria/fungi Antibiotic treatment according to type of bacteria/fungi & susceptibility test.& susceptibility test.

Antibiotic therapy Antibiotic therapy must continue for must continue for at least a monthat least a month.. .. Most patients respond rapidly to appropriate Most patients respond rapidly to appropriate antibiotics and becoming fever free within 1-2 weeks.. antibiotics and becoming fever free within 1-2 weeks.. Beta-lactam antibiotic/ vancomycin combined with Beta-lactam antibiotic/ vancomycin combined with gentamicin in Gram-positive cocci.gentamicin in Gram-positive cocci.