Some patients with a risk of prolonged hospitalization may be identified preoperatively, the others just after the operation. Optimizing preoperative status and aggressive treatment of complications may have significant influence on the duration of hospitalization in intensive care units. The knowledge of risk factors may facilitate organizational procedures and rational bed management.

We conclude that CVVHDF may be an alternative method of renal support for critically ill children after cardiac surgery in experienced centers, but a significant number of specific complications should be taken into account.

SARS-CoV-2 infection in healthy children is usually benign. However severe, life-threatening cases have previously been reported, noticeably in infants. We must be aware that data on natural history of COVID-19 are still full of gaps, especially as far as pediatric population is concerned. Therefore, it is important to describe rare manifestations of SARS-CoV-2 acute infection in children. Here we present the case of acute hemorrhagic necrotizing encephalitis (AHNE) in a previously healthy, 2-month-old infant with SARS-CoV-2 infection. After 2 days of fever with signs of respiratory tract infection, neurological manifestations appeared: irritability, nystagmus, agitation then apathy. As a consequence of apnea, he required emergent intubation and was transferred to our PICU. Brain MRI revealed diffuse areas of oedema associated with numerous symmetrical changes with punctate hemorrhages in basal ganglia, thalami, brainstem, and cerebral gray matter. CSF was clear with pleocytosis 484 cells/µl, elevated lactic acid and protein. Despite broad microbiological testing only SARS-CoV2 was detected in PCR nasal swab. Therefore, acute hemorrhagic necrotizing encephalitis (AHNE) as a result of COVID- 19 was the most probable diagnosis. The outcome was unfavorable - brain death was confirmed, life support was withdrawn.

SummaryThe systemic inflammatory response is a challenge in the management of paediatric patients undergoing cardiac surgery. Although multi-factorial, a contribution by the lectin pathway of complement activation has been postulated. We therefore investigated the changes in serum levels of mannose binding lectin (MBL) and activities of MBL-MBL-associated serine protease (MASP)-1 and MBL-MASP-2 complexes immediately before and during surgery, throughout the first postoperative day and at discharge from the hospital. These changes were analysed in relation to postoperative complications. Blood samples were obtained from 185 children with congenital heart disease undergoing surgical correction with the use of cardiopulmonary bypass: preoperatively (MBL-1), 15 min after initiation of cardiopulmonary bypass (CPB) (MBL-E), 30 min (MBL-2), 4 h (MBL-3), 12 h (MBL-4) and 24 h (MBL-5) post-CPB and at discharge from hospital (MBL-K). Alterations in serum MBL levels were calculated as a ratio of its serum level at subsequent time-points (MBL-2, -3, -4, -5) to the preoperative (MBL-1) value. Decreases in MBL and MBL-MASP complexes were observed in all samples, correlating with a decrease in C4 and increase in C4a, confirming activation of the lectin pathway. Changes in MBL levels between children with an uncomplicated postoperative course and those suffering from infection or low cardiac output syndrome did not differ significantly, but significant differences were observed between the SIRS and non-SIRS groups. Paediatric cardiac surgery with the use of cardiopulmonary bypass activates the complement system via the lectin pathway and the latter contributes to the development of the post-bypass systemic inflammatory response.

Cardiovascular disease remains the leading cause of mortality and morbidity worldwide so research continues into underlying mechanisms. Since innate immunity and its potent component mannan-binding lectin have been proven to play an important role in the inflammatory response during infection and ischaemia-reperfusion injury, attention has been paid to its role in the development of cardiovascular complications as well. This review provides a general outline of the structure and genetic polymorphism of MBL and its role in inflammation/tissue injury with emphasis on associations with cardiovascular disease. MBL appears to be involved in the pathogenesis of atherosclerosis and, in consequence, coronary artery disease and also inflammation and tissue injury after myocardial infarction and heart transplantation. The relationship between MBL and disease is rather complex and depends on different genetic and environmental factors. That could be why the data obtained from animal and clinical studies are sometimes contradictory proving not for the first time that innate immunity is a “double-edge sword,” sometimes beneficial and, at other times disastrous for the host.