In last article we investigated influence of a condition of a system of immunity on the course of a koronavirusny infection. Now we will talk about COVID-19 stages in terms of an immune response.
So, a number of researchers allocates the system of classification from three steps according to which COVID-19 has three stages with increase on severity which corresponds to concrete clinical indicators, reaction to therapy and a clinical outcome of a disease.
The first stage (easy) — an early stage of an infection. The initial stage comes during inoculation of a virus and the early beginning of a disease. For most of people this stage includes the incubation interval connected with easy and often nonspecific symptoms, such as indisposition, fever and dry cough. During this period of SARS-CoV-2 breeds and fixed in the owner's organism, first of all, in a respiratory system. Like the older relative, SARS-CoV (responsible for flash of SARS in 2002-2003), SARS-CoV-2 contacts the target, using a receptor angiotensin - reformative enzyme 2 (ACE2) on cells of the person. These receptors are present at an epithelium of lungs and a small bowel of the person much and also at a vascular endothelium. As a result of an airborne way of transfer and also affinity to pulmonary receptors of ACE2, the infection is usually shown in the form of easy respiratory and system symptoms. Diagnostics of a disease at this stage includes PTsR of a respiratory sample, the analysis of blood serum on IgG and IgM SARS-CoV-2 and also a thorax X-ray analysis, the general blood test (GBT) and control of functions of a liver. OAK can reveal a lymphocytopenia and a neutrophilia if other considerable anomalies are not observed. Treatment at the first stage, first of all, is directed to relief of symptoms. If the efficiency antiviral is proved to therapy, its use for certain patients at this stage can reduce duration of symptoms, minimize degree of transmissibility and prevent progressing of weight of a disease. At patients whose organism can hold a virus only at this stage of COVID-19, the forecast for recovery very good.
The second stage (moderate) — a pulmonary stage without hypoxia (IIa) and with a hypoxia (IIb). At the second stage at the established pulmonary disease reproduction of a virus and the localized inflammation in lungs is typical sign. At this stage at patients viral pneumonia with cough, fever and sometimes the hypoxia (defined as PaO2/FiO2 <300 mm Hg develops.). Tool diagnostics by means of the roentgenogram or a computer tomography of a thorax reveals bilateral infiltrates or a symptom of opaque glass. Blood tests reveal increase in a lymphocytopenia. Markers of system inflammation can be raised, but is not so noticeable. At this stage most of patients with COVID-19 need hospitalization for careful observation and treatment. Treatment has to consist, generally of the supporting measures and available antiviral therapy. It should be noted that pro-calcitonin level in blood serum in most cases of pneumonia of COVID-19 is low or normal.
Stage III (heavy) — system hyper inflammation. A smaller part of patients with COVID-19 will pass into the third and heaviest stage of a disease which is shown as a syndrome of extra pulmonary system hyper inflammation. At this stage the level of markers of system inflammation is raised. The infection of COVID-19 leads to decrease in quantity T-helperov, T-suppressors and T-regulators. Researches showed that patients at this stage of heavy course have diseases inflammatory cytokines and biomarkers are considerably raised. At this stage shock, a vazoplegiya, respiratory insufficiency and even cardiopulmonary collapse are possible. Systemic lesion of bodies, even myocarditis can be shown. Individual therapy at a stage of III is connected with use of immunomodulators for reduction of system inflammation before it results in multiorgan insufficiency. At this stage use of corticosteroids can be justified in combination with use of inhibitors of cytokines, such as totsilizumab (IL-6 inhibitor) or an anakinra (the antagonist of a receptor of IL-1). Intravenous immunoglobulin can also play a role in modulation of the immune system which is in a gipervospalleny state. In general, the forecast and restoration at this critical stage of a disease are unsatisfactory, and fast recognition and use of the described therapy can have the greatest effect.