Журнал «Здоровье ребенка» 4 (55) 2014

Introduction.

Infectious endocarditis is an endovascular infection, affecting endocardium, one or several valves, cardiac septi. Clinical intracardiac manifestations of infectious endocarditis include valvular insufficiency, which may cause fatal cardiac insufficiency.   Leading group of risk factors of bacteremia and infectious endocarditis development include: usage of central venous catheters, catheterization of arterial and venous bed aimed at diagnostic and treatment, necessity of controlling hemodynamic parameters. Herewith, risk of infection grows along with increase of diameter of catheter and its adhesive properties. Catheter-associated infections of the blood flow lead not only to increase of terms of hospital stay but to the increase of lethality rate, especially among children with congenital heart defects. The most often in case of catheter-associated infections various strains of staphylococcus are isolated from the blood. 

Materials and methods.

In the article a case of infectious endocarditis, developed in post-operative period in a child aged 1 year 10 months with Down’s disease, multiple congenital defects of heart development and those of gastro-intestinal tract is presented. Final clinical diagnosis: Down’s disease. Multiple congenital defects of development: congenital heart defect (full atrio-ventricular communication. State after radical correction). Congenital defect of gastro-intestinal tract development: ring-shaped pancreas with a syndrome of a high intestinal obstruction. Post-operation state: laparotomy, duodenum-jejunum anastomosis, Brawn’s anastomosis. Complication of the main disease: infectious endocarditis, sub-acute course, septicemia. Marked mitral insufficiency. High pulmonary hypertension. Comorbidities: severe ischemic-hypoxic encephalopathy of mixed genesis, mixed tetraparesis, convulsive syndrome, pseudo-bulbar syndrome. Retardation of psycho-motor development. 

Results.

By the anamnesis data in the neonatal period in a child there was diagnosed congenital heart defect: complete atrioventricular communication, balanced form. At the age of 6 months a radical correction of atrio-ventricular communication was performed. Early post-operative period was complicated by cardiac insufficiency, which was corrected by administration of sympathomimetics. In post-operative re-bypass of interatrial baffle patch defect of minimal sizes, severe mitral insufficiency and high pulmonary hypertension were diagnosed.  

The first episode of state worsening appeared in 6 months after surgical intervention, with complaints on marked weakness, food refusal, dyspnea at rest, constant febrile fever. When seeking for doctor’s advice, general state is severe, caused by marked intoxication syndrome, manifestations of cardiac insufficiency and significant disorder of microcirculation. After complex of intensive therapy and stabilization of clinical state, child was transferred into pediatric unit at place of residence for rehabilitation.

The last episode of state worsening was caused by aggravation of intoxication syndrome, respiratory disorders, signs of severe cardiac insufficiency, constant febrile fever. Child was hospitalized into intensive care unit. Results of paraclinical examinations showed: leucocytosis, neutrophilia with the shift to the left. In the blood culture on sterility Staphylococcus aureus was isolated. Doppler-echocardiography: all cardiac cavities are full dilated, thickening of inter-ventricular septum, moderate increase of pressure in the pulmonary artery. In the cavity of the left atrium – hypoechogenic mass of irregular form – thrombus was revealed. Fibrosis of mitral valve cusps, mitral regurgitation of the third degree, tricuspid regurgitation of the second degree. In computer processing of echocardiogram there was revealed a moderate increase of ultrasonic density of left ventricle endocardium, significant increase of ultrasonic density of endocardium of interventricular septum, sharp increase of ultrasonic density of the anterior cusp of mitral valve and posterior papillary muscle, significant thickening of the anterior cusp of mitral valve (0,41 cm). Ultrasonic density of pericardium of the right and left ventricles is moderately increased.

Over the period of staying in intensive care unit, state of the child remained refractory severe. Despite intensive therapy, polyorganic insufficiency was progressing, this resulted in heart failure and biologic death.

Results of autopsy (Protocol № 366) of circulatory system organs showed that leaves of pericardium are in dense adhesion against each other. Epicardium is thickened, loose, faded. Cavity of the left atrium is full dilated, filled with elastic blood clot of 1,5 cm in diameter. Papillary muscles of the left and right ventricle are thickened. Endocardium over the whole route is of rose color, smooth, faded. Myocardium of the left and right ventricular wall is thickened. Mitral valve cusps are thickened, tuberous, opaque, with ball-like thickness of up to 0,2 cm in diameter, without dense adhesion. Semilunar cusps of the aorta are smooth, transparent. Aorta intima is of pale-yellow color, smooth, pellucid. Histologic investigation: in the heart –granular and vacuole dystrophy of myocardiocytes, interstitial edema, vascular hyperemia with extravasates. Mitral valve cusps are thickened due to fibrosis, fibrin stratification with admixtures of lymphocytes, histiocytes. Focal vegetations of granulation tissue. In the cavity of the right atrium – thrombus presented by fibrin, infiltrated with leucocytes, hemolyzated erythrocytes. Coincidence of clinical and postmortem diagnosis.

Comparing data of life-time echocardiographic examination with those of postmortem and histologic investigation on autopsy showed coincidence of data. Sharp increase of ultrasonic density of cusps and significant thickening of the anterior cusp of mitral valve corresponded to the presence of fibrosis of mitral valve cusps on autopsy. Absence of changes of ultrasonic density of aorta walls and aortal valve corresponded to absence of pathomorphological changes on autopsy. Moderate increase of ultrasonic density of endocardium of the left ventricle corresponded to moderate pathomorphological changes of endocardium on autopsy. Increased ultrasonic density of pericardium corresponded to presence of morphologic changes presented as pericardium fibrosis on autopsy. Conclusions.

The clinical case elucidated role of risk factors in the development of infectious endocarditis in the child: presence of congenital defect of the heart, more than one operative intervention, prolonged intravenous usage of medications by means of venous catheters, bacteremia presence. Clinical case proved correlation of data of echocardiographic examination of ultrasonic density of cardiac membranes and structures with those of postmortem and histologic investigation.