What is Infective Endocarditis

Definition

Syndrome arising from a microbial infection of the endothelial surface of the heart (mainly localized in the heart valves) caused by bacteria, fungi, rickettsiae, mycoplasmas and chlamydia.

Cardinal Features

  • The symptoms are nonspecific and include fever and sweating.
  •  Signs include: new onset heart noise systemic emboli and splenomegaly.
  •  Drug addicts and patients undergo cardiac surgery are particularly susceptible to this infection.
  •  Acute, subacute and fulminant forms.

The most commonly affected is the mitral valve, followed by aortic, tricuspid and most rarely pulmonary valve.Mural endocardium may also be affected and may develop intramiokardni abscesses. When drug addicts are mainly affects the left heart half.

The acute disease is fulminant development and leads to destruction of the flap, the formation of abscesses and metastatic infection. Subacute disease develops over months and is manifested mainly with metastatic infections.

Causes

Streptococci

  • Streptococcus viridans is the cause of the disease in 50-60% of cases in patients and artificial heart valve.Associated with subacute disease.
  • Streptococcus Bovis is cause primarily in patients with artificial heart valve and gastrointestinal malignancy or polyps in the colon.The most commonly seen in older patients.
  • Streptococcus intermedius can cause acute and subostro disease.
  • Streptococcus pneumoniae can cause illness in patients with normal aortic valve.Alcoholism is a risk factor.
  • Enterococci are associated with pre gastientistinalni manipulations and cause mainly in adults.

Staphylococci

  • Staphylococcus aureus is the most common cause of acute disease.The infection primarily affects the left heart half.
  • Coagulase negative staphylococci cause infection affecting artificial valves in the first year of their placement.Staphylococcus epidedermidis is the most common cause.

НАСЕК групата от Gram (-) бацили: H.parainfluence; H.aphrophillus; Actinobacillus actinomycemcomitans;Cardiobacterium hominis; Eikenella & KINGELLA.

Rare causes

  • Fungi: Candida and nekandida species, mainly after placement of a central venous catheter or after cardiac surgery.
  • Pseudomonas aeruginosa, mostly in drug addicts.
  • Listeria monocytogenes, primarily in patients with heart malformations.
  • Gram (-)kokobatsili: Bartonela has primarily been observed in patients who have cats; Legionella and Nayseriya is mostly seen in patients with artificial heart valves.
  • Atipichni mikobaktyerii
  • Polymicrobial causes: pseudomonas and enterococci are the most common combination.
  • Koksiela Burnett (the Q fever): transmits through cats and rats. Patients with abnormal heart valves are particularly sensitive, prolonged infection leads to the development of subostar endocarditis.
  • Chlamydia: infection with this cause to suspect in blood culture negative patients.

Predisposing factors

Heart conditions

  • Artificial heart valves
  • Previous episode of infective endocarditis
  • Rheumatic heart disease
  • Valve abnormalities: vkl.hipertrofichna subvalvular aortic stenosis;mitral valve prolapse with regurgitation; congenital valvular abnormalities
  • Endocardial anomilii caused by blood flow in congenital abnormalities, ventricular septal defect, tetralogy of Fallot, coarctation of the aorta, patent ductus arteriosus
  • Intracardiac pacemaker
  • Hypertrophic cardiomyopathy
  • Degenerative valvular disease in adults
  • Application of apetitosupresivni preparations

Diabetes

Chronic renal disease

Recent prolonged and transient bacteremia

immunosuppression

  • Addiction
  • Malignancy
  • KhIV
  • Organ Transplantation

Bad habits

  • Alkolizam

Epidemiology

1-4 new cases per 10,000 people per year.

Higher frequency in hemodialysis patients.

Mostly women aged under 35 years.

In men, the most frequently observed in age between 45-65 years.

Men are affected twice as often than women.

Clinical Presentation

Signs of infection: fever, night-sweats, malaise, weight loss, anemia, splenomegaly.

Cardiac: new onset or worsening heart noise characteristics of the existing one tezhkostepenna signs of valvular regurgitation, levoventrikularna weakness, prolonged PR interval if abscess at the base of the aortic root.

IMMUNOLOGICAL phenomenon, the micro, macroscopic hematuria, glomerulonephritis, generalized vasculitis, arthralgia; petechiae at the base of the nail bed, Osler nodes, lesions Janeway (palmar painful erythematous macula); retinal haemorrhages, Roth spots on the retina. Immunological phenomena do not develop acute disease are not observed also in right ventricular involvement.

Systemic embolism, cerebral, retinal, renal, splenic, pulmonary (for right-sided endocarditis), liver; can develop abscesses or mycotic aneurysms.

Diagnostic decision

In kraktikata using the criteria of Duke. The diagnosis is positive if the two main criteria, one major and three minor criteria or 5 minaret criteria.

Main criteria:

  • Positive blood culture-it is necessary to have 2 consecutive positive blood cultures
  • Evidence of endocardial involvement detected by echocardiography

Minor criteria:

  • Presence of predisposing factors for developing infective endocarditis
  • Body temperature above 38 degrees
  • Vascular phenomena: major arterial emboli in;septic pulmonary infarction; mycotic aneurysms;intracranial hemorrhage; conjunctival haemorrhage
  • Immunological Phenomena
  • Positive blood culture, understood one positive blood culture
  • Echocardiographic findings associating with infective endocarditis, but not falling under the heading of the main criteria

Laboratory researches

Blood cultures : they are key diagnostic kits. Take 3 consecutive blood cultures (6 bottles). It should be borne in mind that Koksiela, Bartonela, Legionella and Chlamydia do not grow in standard blood cultures.

Other laboratory tests : they are useful for proof of sepsis and monitoring the effect of therapy

  • Peripheral blood counts: normochromic normocytic anemia and polymorphonuclear leukocytosis are common finding.They can be observed also thrombocytopenia and thrombocytosis.
  • Urea and electrolytes, renal dysfunction is a complication of sepsis.Electrolyte disturbances should be identified and treated, otherwise the patient is prone to developing arrhythmias.
  • Liver function tests: there is increased alkaline phosphatase.
  • Inflammatory markers: C-reactive protein and erythrocyte sedimentation rate are non-specific markers that are positive for at each infection.
  • Immunoglobulins and compliment: serum immunoglobulins are increased, but total complement and C3 are reduced due to the development of immune complexes (in 70% of cases).
  • Urine: proteinuria and microscopic hematuria are almost always available.
  • Polymerase reaction: used to identify specific DNA in blood, urine or surgical biopsy.

Electrocardiogram , may indicate the presence of coronary syndrome (due to coronary embolization) or conduction defects.

Sightseeing Earl of lung and heart , can display data characteristic of cardiac needostatachnost, multiple pulmonary emboli or abscesses. The combination of sepsis and pulmonary infiltrates have to point to the possibility of right-sided endocarditis available.

echocardiography

  • Transthoracic echocardiography is rapid, non-invasive, but operator dependent method (sensitivity 65-70%) to visualize vegetations.It is also useful to establish the valve malfunctions and other local complications such as abscess aortic root.
  • Transezofagialnata echocardiography method is sensitive down abscess formation, and is recommended to be carried out in all patients with artificial heart valves, in which are suspected endocarditis.

Differential Diagnosis

Acute rheumatic fever

It was delayed consequence of infection of the upper respiratory tract by group A streptococci. Patients with rheumatic fever may also be present with fever and new onset sardichen noise. Most often, however, patients are varzrast 5-15 years, elderly patients have a positive history of previous episodes of rheumatic fever. Acute episodes occur 2-3 weeks after pharyngitis. Migratory polyarthritis observed in most cases.

Atrial Myxoma

Represents benign gelatinous formation originating interatrialniya septum of the heart in the fossa ovalis.

The most common manifestations are: chest pain, syncope, dyspnea and edema.

Auscultation may find noise characteristic of mitral inzuficienciя.

Systemic lupus erythematosus

Chronic multisystem disease of autoimmune origin occurring with characteristic skin and joint disease, although all systems can be affected. Heart engagement may mimic endocarditis, myocarditis or pericarditis, more availability of oportyunostichni infections because of immunosuppression is a common phenomenon.

Acute glomerulonephritis

May develop as an immunological response against various infections, the most common streptococcal.Acute glomerulonephritis can be a complication of infective endocarditis. Acute symptoms develop 10-14 days after infection. There are hypertension, hematuria and oliguria as well: facial edema, headache and pain in the lumbar region.

Nonbacterial thrombotic endocarditis

Observed in patients with hiperkoaguloabilitet mostly malignancy, and in severely ill patients napr.takiva with HIV. Embolic events can be seen in these sterile growths.

Periakrdit

Pericarditis is infmalatorno or an infectious inflammation of the pericardial sac, which can be acute or chronic. Chest pain is a symptom prominirasht most often locates in retrosternal region. Dyspnoea and pericardial friction noise are the most common manifestations.

Renal Cell Carcinoma

Renal cancer is a tumor that is distributed through the vascular system and by direct invasion of other organ structures and lymph nodes. The classic triad is: hematuria, abdominal mass and pain in the back.Fever, anemia and weight loss also may be present.