Thrombotic Microangiopathy Triggered by COVID-19: Case Reports

SARS-CoV-2 causes thrombotic microangiopathy (TMA) through the activation of an alternative and lectin complement pathway. TMA is one of the main reasons for acute kidney injury development in patients with COVID-19. In this study, we present 3 TMA cases with severe kidney injury triggered by SARS-CoV-2. In the absence of other TMA causes, we diagnosed the atypical hemolytic uremic syndrome, triggered by SARS-CoV-2 due to abnormal complement activation. Because of both coagulation factors activation, and the high level of D-dimer in patients with COVID-19, it is crucial to differentiate disseminated intravascular coagulation from TMA. The use of anticomplement therapies such as eculizumab should be considered in refractory cases of progressive COVID-19. Controlled clinical trials are required before a definitive statement can be made.

THE HEART DAMAGE AND ITS STRUCTURAL STATE FEATURES IN MEN UNDER 60 YEARS OLD WITH MYOCARDIAL INFARCTION, COMPLICATED WITH ACUTE KIDNEY INJURY

Relevance. The role of hemodynamic changes in myocardial infarction complicated by acute kidney injury is interpreted in different ways. Aim. To evaluate the heart chambers and structures peculiarities in men under 60 years old with myocardial infarction complicated by acute kidney injury to improve prevention and outcomes. Material and methods. The study included men 19-60 years old with type I myocardial infarction. The patients were divided into two age-comparable groups: I - study group, with acute kidney injury - 25 patients; II - control, without it - 366 patients. A comparative assessment of the heart chambers and structures parameters in the first 48 hours (1) and at the end of the third week of the disease (2), their dynamics, also acute kidney injury development risk analysis (ANOVA) were performed. Results. The study group differed from the control group in smaller sizes of the left atrium2 (38.1±6.0 and 42.0±5.4 (mm), respectively; p=0.01), a higher frequency of the middle anterior (100 and 15.6%; p=0.02) and antero-septal (100 and 17.7; p=0.04) segments akinesia and the absence (0 and 81.5%; p=0.04) of tricuspid regurgitation. In the study group, there was a smaller increase in the ventricles size than in the control group (left: 0.6 and 1.7%, respectively; right: 15.3 and 33.6%) and a greater decrease in the atria size, compared in the control group (left: -1.8 and -25.3%; right: -25.3 and -0.1%) (p<0.0001). The risk markers of the acute kidney injury developing were the dimensions of the left atrium1˂34 mm, interventricular septum≥12.0 mm, end systolic1≥4.23 and diastolic1≥5.3 of the left ventricle, right ventricle1˂2.6; of the right atrium1≥4.7 (cm), the mass of the left ventricle1≥328.8 g. Conclusions. Men under 60 years old with acute kidney injury in myocardial infarction are characterized by lesions of the middle anterior and antero-septal segments, the absence of tricuspid regurgitation, and a smaller left atrium in the subacute period of the disease. The above of the heart chambers dimensions values should be used in the high-risk groups for the acute kidney injury development formation, as well as for prognostic modeling.

THE SYSTEMIC CIRCULATION IN MEN UNDER 60 YEARS OF OLD WITH MYOCARDIAL INFARCTION AND ACUTE KIDNEY INJURY

Relevance. Hemodynamics changes in myocardial infarction complicated by acute kidney injury are interpreted in different ways. Aim. To evaluate peripheral hemodynamics changes in men under 60 years old with myocardial infarction complicated by acute kidney injury to improve prevention and outcomes. Material and methods. The study included men 19-60 years old with type I myocardial infarction. The patients were divided into two age-comparable groups: I - study group, with acute kidney injury - 25 patients; II - control, without it - 486 patients. A comparative assessment of circulation indices changes in first 48 hours (1) and the end of third week disease (2), their dynamics, also acute kidney injury development risk analysis (ANOVA) were performed. Results. The study group differed from the control group in lower values of heart rate1 (66.3±12.2 and 75.8±18.8 (bpm), respectively; p=0.003) and higher - arterial pressure, systolic1 (155.6±24.0 and 139.5±28.9 (mm Hg); p=0.006), diastolic1 (98.0 ± 16.0 and 86.6 ± 18.9 (mm Hg); p = 0.002), mean1 (117.2±17.6 and 104.3±21.3 (mm Hg); p=0.001). In the study group compared in the control group, there was a greater decrease in blood pressure (mean: -18.3 and -8.3%, respectively) and total peripheral resistance (-33.5 and -26.3%) (p<0.0001). The risk markers of the acute kidney injury development were the mean arterial pressure1≥106.7, systolic1≥140.0, diastolic1≥90.0 (mm Hg) and heart rate1˂66 bpm. Conclusions. Men under 60 years old with acute kidney injury in myocardial infarction are characterized by arterial hypertension and bradycardia in the first hours of the disease, as well as more pronounced decline dynamics of blood pressure and total peripheral resistance at the end of its subacute period. The listed above values of the circulation parameters should be used in the high-risk groups for the acute kidney injury development formation, as well as prognostic modeling.

RENAL COMPLICATIONS OF COVID-19 CORONAVIRUS INFECTION: MECHANISMS AND BIOMARKER

The brief review dealing with risks of the development of renal complications in patients with COVID-19, peculiarities of acute kidney injury development in patients with coronavirus. The special attention is given to the mechanisms of the direct infection of kidney by coronavirus SARS-CoV-2 and to the biomarkers for differential diagnostics of glomerular and tubular dysfunction in patients with COVID-19.

The role of cystatin C and various methods of glomerular filtration rate calculation in evaluation of renal dysfunction in children with acute infectious diarrhea

Rationale: Acute infectious diarrhea (AID) is the fourth leading cause of death among children <5 years worldwide. Kidney damage is one of the poorly studied aspects of pediatric AID. The level of serum cystatin C is independent on gender and age, and it is highly informative even in the early stages of renal dysfunction.Aim: To optimize diagnosis of renal dysfunction in children with moderate AID through comparison of different methods of glomerular filtration rate (GFR) calculation and determination of serum cystatin C level.Materials and methods: Observational cross-sectional study enrolled 80 children in pediatric hospital with moderate AID not followed by hemolytic uremic syndrome. Serum creatinine and serum cystatin C levels were determined in all the patients in acute period with GFR calculating according to Schwartz equation in unmodified (1976) and modified (2009) versions. GFR was also calculated using a single-factor equation based on serum cystatin C level.Results: GFR in acute period, calculated according to unmodified and to modified Schwartz equation was in patients <3 years (n=40) 115.47±3.33 ml/min/1.73 m2 and 98.56±2.84 ml/min/1.73 m2 (p<0.001), in patients 3–7 years 132.13±4.2 ml/min/1.73 m2 and 108.85±3.84 ml/min/1.73 m2 (p<0.001), respectively. Increased serum cystatin C level (>950 ng/ml) occurred in 18 patients (22%). In other patients level of serum cystatin C remained within the reference range or lower. The risk of acute kidney injury development based on two indicators – GFR according to the modified Schwartz equation and GFR according to the equation used cystatin C level – occurred in 4 (10%) patients aged 1–3 years and in 1 (2.5%) child in the age group 3–7 years; risk, based on one indicator – the calculation of GFR according to the formula using cystatin C – in 8 (20%) and 9 (22.5%) children, respectively, and based on the assessment of only GFR according to the modified Schwartz equation – in 3 (7.5%) children of both age groups.Conclusion: We have confirmed that the GFR values calculated with usage of unmodified Schwartz equation (1976) are higher than those calculated with usage of modified Schwartz equation (2009) and taking into account the level of cystatin C. Thus, usage of unmodified Schwartz equation for GFR calculation in infants and preschool children seems incorrect. Level of serum cystatin C is promising marker permitted to select patients with risk of acute kidney injury development among children in acute period of moderate AID.