Sunday, April 14, 2013

Bacterial endocarditis


The essence of diagnosis 

Subacute:

• A patient with rheumatic or congenital heart disease.
• Long-term fever, weight loss, joint pain and muscle pain, fatigue and anemia.
• heart murmur splenomegalia, petechiae, emboli phenomena.
• Blood culture was positive.



Acute:

• Patients with acute infection, a history that iliskorim jerađena surgery.
• High temperature, sudden changes or new noises, pojavaembolija, petechiae, splenomegalia itoksične phenomenon.

General assessment

Subacute bacterial endocarditis (SBE) is a bacterial infection of the endocardium flammable, and usually builds on rheumatic or valvular or caicifikovano changed to a congenital heart disease. The initial cause of bacteremia were respiratory infections, interventions to teeth or cystoscopy. But in most cases the source of infection is not known. Etiologic factors are usually nonhemolytic Streptococcus, Streptococcus viridans and especially S. faecalis, stapholococcus occasionally, but every other organism is viable.


Bacteria settle the endocardium valve (usually aortic and mitral) or more valves. Precipitated fibrin and platelet thrombi form so that the form of vegetation that are weathered and torn easily give emboli to the brain, peripheral artery or visceral organs. Embolični nephritis or glomerulonephritis true sometimes can lead to kidney failure. Dissemination of bacteria in the blood, but altered valve can lead to the development of mikotične aneurysm, which sometimes, however, rarely, it can rupture. May be present and active rheumatic carditis. SBE develop moderate to moderate systemic symptoms: cerebral, renal, splenic or mesenteric embolism, heart failure, or any combination of these that. After this may bacterioremia from one of the sources, and in the course of a few days or weeks.

Acute bacterial endocarditis (ABE) is a progressive infection of normal speed or variable valve and usually develops in severe bacteremia from acute infections, such as eg. pneumococcna pneumonia, postabortalna pelvic infection or abscess. It can also occur as a complication after surgery on the heart, transurethral postatecoomije, or after surgery on the infected tissue. The most common pathogens are challengers: Pneumococci, hemolytic staphvlococc, betahemolitični Streptococcus and gram negative coliform organisms.

Acute endocarditis creates great weathered forms of bacteria that lead to the occurrence of severe emboličnih with metastatic abscess, perforation fast, breaking and destruction of the changed valve chordae tendineae or rupture.

The clinical picture

A. Symptoms and signs: fever is present in all cases, although there may be afebrile period. Individually or as a whole may be present following symptoms: sweating at night, chills, malaise, fatigue, anoreksia, weight loss, vague muscle aches, artralgia, redness and swelling of joints, sudden changes in the eyes, aphasia, hemiplegia caused by cerebral embolism, abdominal pain, chest pain, changes on one side of the body caused by mesenteric, spleničnim, pulmonary embolism, renal, bleeding from the nose, bruises and symptoms of heart failure. The ABE is more turbulent flow and the patient was very intoxicated.

The SBE is usually a rheumatic or congenital heart disease. Available when the tahikardia, splenomegalia, petechiae on the skin and mucous membranes, and then finding the fundus, and bleeding under the nail more available; batičasti fingers and toes, pale or tan skin, neurologic findings following cerebral embolism, sensitive red nodules on fingers and legs. Heart murmurs can be considered irrelevant when it comes to infections trikuspidalnih valves and valvular pulmonary artery. However, with repeated pulmonary infarction due to pneumonia, heart murmurs can be very characteristic signs.In elderly patients clinical presentation is often atypical.

ABE is, in fact, a serious infection associated with fever, high fever, extreme iznemoglošću serious and multiple occurrences embolism. This can be down linked to previous causal infection (pneumonia, furunculosis, pelvic infection) or may occur suddenly after surgery. Heart murmurs can change rapidly, and heart failure expires earlier.

ABE may develop during prophylactic treatment with antibiotics and inadequate. In these cases, the changes are masked, and the first warning can occur suddenly embolism, then petechiae, unexpected heart failure, altered noises or fever.

B. Laboratory findings: if the suspected SBE is necessary to take two blood cultures daily for a period of 3-5 days. For 2-7 days of incubation, 85-95% of these cultures to isolate organisms and allow the selection of a special drug. The ABE is necessary to take 2-3 blood culture during the emergency treatment of patients, and then start with antibiotic therapy. In the case of repeated negative blood cultures (in uremic patients) is necessary to make the culture of bone marrow.

The effect of drugs on antimikorbnih positive blood cultures can be expected in 10 days.

Normochromic anemia, expressed sedimentation, leukocytosis, microscopic hematuria, proteinuria, and effusions are often found in the SBE and ABE. Especially in adult patients nitrogen retention may be the first sign. In 50 - 60% of cases there is rheumatoid factor when it comes to the SBE that has lasted for more than 6 weeks.

Complications

Complications in the presence of ABE and SBE may include peripheral arterial embolism (leading to hemiplegia or aphasia; bowel infarction, kidney or spleen, or acute arterial insufficiency of the hands or feet, congestive heart failure, renal failure, krvaljenje, anemia, and create metastatic abscesses ( especially when it comes to ABE). splenic abscess may adversely affect the effect of therapy, and even lead to the initial state.

Differential Diagnosis

SBE must be differentiated from patients with a variety of similar conditions. Hemiplegia, persistent heart failure, anemia, bleeding fondness or uremia may be caused by the SBE. If a patient has of any of these diseases in addition to temperature and even a heart murmur, it is necessary to take haemoculture.

Specific illnesses that require you to differentiate are: lymphoma, thrombocytopenic purpura, leukemia, acute rheumatic fever, diseminatni lupus erythematosus, polyarthritis nodosa, chronic meningococcemia, brucellosis, diseminantna or miliary tuberculosis, non-bacterial thrombotic endocarditis or chronic disease with weight loss.

ABE cover a severe systemic reaction to the apparent pre-existing infection. It can be recognized only if notice the rapid clinical deterioration, bacteriemia, the occurrence of sudden cardiac noise changes, heart failure and high embolične attacks, especially in the CNS, which give a picture of meningitis.

Preventive measures

Some cases of endocarditis can occur after surgery on the teeth, oropharynx, and genitourinary tract.Patients with known heart anomaly must be for the above-mentioned surgery to prepare the following:
(1) 600,000 units procaine penicillinasa 600,000 units of crystalline penicillin. They are administered one hour before surgery, and then procaine penicillin 600,000 units daily to them within two days.
(2) 500,000 units of penicillin G or oral Vper 4 or 5 times a day I danhirurške intervention and two days after the execution of the intervention.
(3) In the case of sensitivity to penicillin, iliu persons who received penicillin in the prophylaxis of rheumatic fever, it is necessary to prescribe erythromycin 250 mg orally four times daily on the day of surgery and two days after the procedure.
(4) When it comes to surgery on the genitourinary or gastrointestinal tract should be given streptomycin, 1-2 gm per day, apart from the point of therapy (1).

Treatment

A. Special measures: the value of understanding regarding the treatment of bacterial endocarditis is a bactericidal antibiotic concentrations in contact with infectious organisms, which is often localized in avascular tissue, or in a place where bacteria develop. By far the most effective drug in the treatment of bacterial endocarditis is penicillin because of its high degree of bactericidal activity against most of the bacteria that cause bacterial endocarditis and because of the small number of side reactions. When necessary, the synergistic effect of antibiotics proved to be useful. Several cases have been cured only by using bacteriostatic drugs.

Positive blood cultures do not have this value to confirm the diagnosis and to be a landmark in the treatment of sensitivity tests to different antibiotics or combination of antibiotics. Before you start the treatment you need to take two blood cultures daily for a period of 3-5 days, except in cases of very severe patients where antibiotic treatment administered immediately after the emergency treatment of patients, including blood cultures 2-3.

Note: control of the antimicrobial treatment.

Blood cultures were negative minimum initial requirements for the implementation of effective therapy.Since the start of treatment serum bactericidal activity test is the best indicator to support the selection of drug and dose. During treatment the serum of patients should be bactericidal under standard laboratory conditions. Serum diluiran 1:5 or 1:10 should be rapidly bactericidal.

First Penicillin is the drug of choice in most cases of bacterial endocarditis. At first it is necessary to prescribe parenteral all patients until an adequate serum bactericidal. Per oral administration of medication can be carried out in those cases where it is a particularly sensitive organism and it is possible to implement control per oral ingestion (5 times greater than parenteral) and you can keep an adequate level of serum.

Dosage of penicillin is depending on the sensitivity of the organism. Streptococcus viridans is sensitive to 0.1 units / ml penicillin (over 8096) can be treated bacterial endocarditis administration of penicillin G, 3-5 million units per day in 3-4 weeks. Given them 1.2 million units procaine penicillin 3 times a day.Streptococci are killed using 1.0 but not using 0.1 units / ml penicillin G, which requires (dissolved in water), 5-10 million units per day in 3-4 weeks. Antibiotic can prescribe them or iv streptococci and other organisms that die of penicillin in a concentration greater than 1.0 units / ml, requiring more than 10 million units of penicillin G, which is usually administered in the form of intravenous drip infusion (5% glucose or saline solution). You need to pay attention to the following complications: (a) Each million units of "potassium penicillin" contains about 1.7 milliequivalents potassium approaching the toxic dose, (b) at high concentrations of penicillin a lot of diffusion in the CNS and thus leads to the neurotoxic state, (c) the long-term intravenous antibiotic therapy, there is the possibility of superinfection, to avoid this it is necessary to change every 48 hours post injection and all work under strict aseptic conditions.

If bakteriemia and signs of bacterial endocarditis persistent active dose may be increased (and may provide 500 million units of penicillin G per day) until the serum is not the exam, and clinical signs do not become satisfactory. However, if a negative blood culture and serum testing has shown that it is necessary to prescribe the appropriate remedy. The signs and symptoms that occur may be caused by other factors and not only by infection.

Second The combined effect of penicillin and streptomycin or kanamvicina. - Appendix kanamvcina streptomycin or penicillin bactericidal activity increases in many of streptococcus, especially for enterococe (S. faecalis). Bacterial endocarditis With caused by the streptococcus viridans streptomvcinsulfat injected them 2-3 times a day, 10 days (penicillin is added as gorerečeno). The overall time of treatment can reduce the seovako 18-22 days (instead of the 3-4nedelje). In bacterial endocarditis caused enterococima given streptomycin 0.5 gm or 0.5 gm kanamvcin intervaluod in 8-12 hours, while penicillin G (10-60miliona units daily) or ampicillin (8-20gm per day) injected iv for 4 -5nedelja. This combined therapy has been shown capable of destroying enterococa when it comes to bacterial endocarditis, when injected negopenicillin I predstavljajedan of the most useful antibiotic synergism. And a combination of other drugs that are detected through laboratory analysis can bitiod used in the treatment of bacterial endocarditis caused by resistant microorganisms in particular, but all this must be uraditipod strict laboratory control.

3rd Cephalothin given dnevnointravenski 6-12 gm, and is used for bacterial endocarditis caused by staphylococcal infection streptococnomi zapenicillin as a substitute in allergic individuals.Hypersensitivity can occur and some other phenomena nacephalothin. Enterococci are usually resistant.

4th Methicillin given dnevnoi.v 6-24 gm. for a period of 4-6 weeks. Bacterial endocarditis-use your code caused penicillinazom created staphvlococca.Alternativni drugs are Nafcillin, 8-16 gm 4puta oxacillin and 8-16 gm four times a day Uist period. Vancomvoin GM4 is given 2-4 times daily for 2-4 weeks when it comes to bacterial endocarditis caused staphvlococcom.

5th Tetracvclin, erythromycin and other drugs that are mainly a bacteriostatic effect are the drugs of choice when it pitanjubakterijski endocarditis. If ordinirajubolesnicima having fever for unknown reasons, these drugs may temporarily potisnubakteriemiju and lead to symptomatic improvement.However, they did not care able to radically destroy the infection, but the disease progresses allow smetajuu and diagnosis. In bakterijskogendocarditisa caused by the Bacteroides species and other anaerobic bacteria or rickettsia, tetracycline may be the drug of choice. The dosage must be determined on the basis of serology and patient tolerance.

6th In bacterial endocarditis who jeizazvan gram negative bacteria flora gives the interior kanamvcin, 0.5 gm imsvakih 6-12 hours. Once combined and companion drugs to give baktericidnukombinaciju by laboratory tests. Cephalothin can be given alternatively 6-12 gm four times a day. Polymyxin B icolistin have not proven clinical bacterial endocarditis korisnimkod izazvanogPseuđomonas species of organism in spite naznačeneosetljivosti you wear. Only surgical removal of the holder of infection (a "patch" over the septal defect, prosthesis) in the cardiovascular system is able to incubate bacterial endocarditis caused pseudomonasom.Gentamicin sulfate, 3 mg / kg per day odefekta them in some cases caused by the bakterijskogendocarditisa rezistentnimgram negative bacteria. In upotrebiovih drugs need to be addressed in terms of the consequences naeventualne Nephrite, neuroili oto toxicity of their actions. If Upitanju decreased renal function dose SEMORE corrected.

7th In patients with a clinical picture typical for bacterial endocarditis but stalnonegativnom hemoculture empirically given penicillin G, 20-50 million units (daily iv plus streptomycin, 1 gm / day mode for 4 weeks). In this way a treatment of disease will show znatnapoboljšanja. If there is no improvement klničkog within 3-5 days, you should try it with other drugs (see 4, 5 and 6).

8th Monitoring results and the eventual return of the disease. At the end of a lečenjaposle 3-6 weeks, stop must be svomantimikrobnom therapy. 3 days after the blood culture is taken once daily for 4 danauzastopce, and then once a week for 4 weeks, during which time patients neophodnobrižljivo observirati. During this time may result in a greater number of Bacteriological to return, but some are still extended for nekolikomeseci. And embolism and temperature can be during and after successful treatment. alisame are not sufficient basis for re-treatment. Initially well postavljenaterapija bacteriologically proven bacterial endocarditis may prove successful even up to 90%. If the bacteriological status of refunds, the organism must be isolated and retested, and then you need to take more accurate treatment with certain drugs.

Despite the treatment of a large number of patients suffering from bacterial endocarditis progression to congestive heart failure and that within 5-10 years. This mechanical heart failure is partly due to the deformation of valves (valvular perforation, torn chordae) due to bacterial infection, and partly due to the healing process and scarring. Therefore, surgical correction of impaired cardiovascular dynamics as taking part in the management of patients.

B. General assessment: it must be taken and additional treatment as in any difficult infekciji.Ako it is difficult datitransfuziju anemia need blood or red blood cells. Anticoagulant therapy (heparin, bishydroxycoumarin) are not indicated in bacterial endocarditis nekomplikovanimslučajevima and can only contribute to complications such as short krvavijenje.

C. Treatment of complications:

First Infarction sistemnoj circulation in the body usually caused by emboli from levogsrca. Emboli from right heart leading to a heart attack the lungs. Treatment is symptomatic, and anticoagulant therapy sometimes helps. Embolektomija can be taken if odreditačna localization.
Second Heart failure - myocarditis, which is often accompanied by bacterial endocarditis and valvular deformity increases, heart failure can daubrza and requires digitization and salt restriction diet. Such patients is not advisable to prescribe fiziološkirastvor potassium or calcium. even during antibiotic therapy is necessary to think about the possibility of early valve replacement akopostoje signs of progressive and severe heart failure. Because of the poor prognosis and the development of renal progresivneaortne bakterijskogendocarditisa valve replacement can be done but only after 2-3 weeks of successful antimicrobial treatment.
3rd In many patients with endocarditis odbakterijskog the retention of nitrogen due to focal emboličnog nefritisaili glomerulonephritis. This requires ponovnukorekciju dose less frequently and occasionally lečenjeuremije until renal function is not popraviza during antimicrobial therapy.

Forecast

Bacterial endocarditis is generally fatal bacterial infection while not destroyed, but in some cases surgical solution A-V fistula or perzistensa ductus arteriosus may lead to a cure. Poor prognosis in patients with negative blood culture has and prolonged treatment, then those with very high resistance of the organism and that suffered an infection of the prosthesis. If the treatment is completed bacteriological forecast depends on adequate cardiovascular function only about 50% of patients feel good 5 years after cure of bacterial endocarditis. Among the diseased aortic valves have the gravest failure prediction and requires appropriate surgical intervention. What is the worst embolism embolism prognosis that affect the brain. Cerebral embolism and aneurysm rupture mikotične can occur even after treatment undertaken. Reduction in renal function is reversible and can be achieved by early adequate antimicrobial therapy.

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