[Multisystem lesions in orphan diseases: rheumatological aspects of Fabry's disease. Case report].

Fabry-Andersen disease is a genetically determined, progressive disease related to lysosomal storage diseases, linked to the X chromosome, characterized by impaired glycosphingolipid metabolism, due to the deficiency or absence of the enzyme α-galactosidase A. Fabry disease is a multisystem disease and is characterized by damage to vital organs - kidneys, heart, brain, with the occurrence of complications that cause an unfavorable prognosis. Autoinflammation mechanisms with signs of chronic inflammation are involved in the pathogenesis of the disease. One of the features of Fabry disease are clinical manifestations in the form of arthralgia, fever, skin lesions, which are similar to rheumatological diseases. The article presents a clinical observation of the classical type of Fabry disease with multiple organ manifestation, which required differential diagnosis with rheumatological diseases. Rheumatologists are specialists who are involved in the early diagnosis of Fabry disease, so they should have a high awareness of this sphingolipidosis.

[Methods for assessing aberrant and adaptive salience]. / Metody otsenki aberrantnoi i adaptivnoi salientnosti.

The term «salience¼ is most often used to describe «aberrant salience¼, which means assigning false significance to insignificant facts and details, that is inherent to patients with schizophrenia. Most often it is used in combination with «aberrant salience¼, which is understood as the assignment of false significance to insignificant facts and details. The term «adaptive salience¼ is less commonly used and means the «correct¼ assignment of the significance to important biological information. It is believed that in schizophrenia there is a decrease of adaptive salience in combination with an increase of aberrant salience. The concepts of aberrant and adaptive salience are a kind of link between the dopamine imbalance underlying the pathogenesis of schizophrenia and the diverse clinic of the disease. This article provides a review of the literature on methods for assessing, including quantitatively assessment, salience in schizophrenia. The comparison of these methods and their possible clinical and scientific application are provided.

Motor Decision-Making as a Common Denominator in Motor Pathology and a Possible Rehabilitation Target.

Despite the substantial progress in motor rehabilitation, patient involvement and motivation remain major challenges. They are typically addressed with communicational and environmental strategies, as well as with improved goal-setting procedures. Here we suggest a new research direction and framework involving Neuroeconomics principles to investigate the role of Motor Decision-Making (MDM) parameters in motivational component and motor performance in rehabilitation. We argue that investigating NE principles could bring new approaches aimed at increasing active patient engagement in the rehabilitation process by introducing more movement choice, and adapting existing goal-setting procedures. We discuss possible MDM implementation strategies and illustrate possible research directions using examples of stroke and psychiatric disorders.

[Impact of kidney biopsy on the management of patients in the rheumatology department: retrospective study].

BACKGROUND: Kidney involvement is a common manifestation of the systemic autoimmune rheumatic diseases. Kidney biopsy is the gold standard for the diagnosis of kidney diseases, however this method has not yet become the standard-of-care in rheumatology practice. AIM: To assess the diagnostic value of kidney biopsy in the management of patients of the rheumatology department. MATERIALS AND METHODS: In this retrospective observational study we analyzed the medical documentation including kidney morphology findings in the patients of the Department of Rheumatology at Tareev Clinic of Internal Diseases. All patients included in the research had signs of kidney involvement and had undergone needle biopsy of the kidney or re-evaluation of the kidney tissue received previously. RESULTS: From June 2016 to October 2021, 3110 patients were admitted to the rheumatology department. Among them 63 (2%) underwent kidney biopsy and were included in the study. Twenty (32%) were male. Mean age was 42.513.9 years. The most common preliminary diagnoses before kidney biopsy were ANCA-associated vasculitis (n=17), systemic lupus erythematosus (n=12), and AA-amyloidosis associated with inflammatory joint diseases (n=7). In 14 (27%) patients diagnosis was unspecified at the time of biopsy. Among 49 patients with established preliminary diagnosis morphological findings were in line 38 (78%) with the pre-liminary diagnosis. However, in 11 (22%) patients morphological findings resulted in the change of the diagnosis. In all 14 patients with unspecified condition kidney biopsy helped to establish clinical diagnosis. Ultrasound evaluation demonstrated hematoma formation in 18 (31%) patients, and among them two required blood component transfusions. CONCLUSION: Our study demonstrates significant value and safety of kidney biopsy in the patients with autoimmune rheumatic conditions. We suggest that kidney biopsy should be implemented in the management of this category of patients.

[Classification of systemic vasculitis: evolution from eponyms to modern criteria].

Systemic vasculitis is a manifold group of systemic autoimmune diseases characterized by the inflammation of the blood vessels. The first clinical cases of systemic vasculitis were described in the Middle Ages, and most of the currently recognised nosological forms were reported in the first half of the 20th century. The first attempt to create a united classification of vasculitis was performed by P. Zeek in 1952. In the following decades accumulation of the data on the etiology and pathogenesis of different vasculitis guided researchers from different countries in their attempts to improve classification. The main principles of classification were the size of the affected blood vessels, disease etiology and pathogenesis. In 1990 American College of Rheumatology (ACR) published classification criteria for seven forms of the systemic vasculitis, that gave a significant contribution to the conduction of large-scale studies in this field. However, the first international nomenclature of vasculitis was developed only in 1994 during the Consensus Conference in Chapel Hill. Revised and augmented version of this nomenclature was created in 2012 and is still valid. An important step in the development of the classification of vasculitis was a joint project of ACR and EULAR aimed to develop new diagnostic and classification criteria for vasculitis (DCVAS). The first result of this project are the new classification criteria for granulomatosis with polyangiitis, microscopic polyangiitis and eosinophilic granulomatosis with polyangiitis published in 2022. In general, the evolution of the classification of vasculitis occurs under the influence of the progress in the understanding of their etiology and pathogenesis.

[Potential risk factors of atrial fibrillation recurrence after cryoballoon ablation].

Aim      To identify risk factors for recurrence of atrial fibrillation (AF) following cryoballoon ablation (CBA).Material and methods  This prospective study included patients with paroxysmal AF who had undergone CBA (141 patients, median age 60 years, 3% men). The evaluation prior to CBA included clinical instrumental parameters (electrocardiography (ECG), 24-h ECG monitoring, echocardiography, contrast-enhanced cardiac multispiral computed tomography). Also, possible intraoperative indexes that could affect the CBA effectivity, were evaluated. The postoperative follow-up duration was 12 months. Effectivity was assessed during in-person visits at 3, 6, and 12 months, when questioning of patients and 24-h ECG monitoring were performed. CBA was considered ineffective if the patient had recurrences of any atrial tachyarrhythmia longer than 30 sec after the end of the 3-month "blind" period.Results During the 12-month follow-up, recurrences of atrial tachyarrhythmia were observed in 46 (32.6 %) patients. Patients with ineffective CBA more frequently had AF during the first 3 months (71.7 % vs. 11.6 %; р<0.001). Such patients had a history of multiple ineffective treatments with antiarrhythmic drugs (AAD), common pulmonary venous (PV) collector (41.3 % vs. 20.0 %; р=0.008), and stroke/recurrent ischemic attacks (15.2 % vs. 5.2 %; р=0.047). Multifactorial regression analysis showed that the factors of AF recurrence included common PV collector (relative risk (RR) 2.35; 95 % confidence interval (CI) 1.29-4.25; р=0.005), multiple ineffective AADs (RR 1.42; 95 % CI 1.08-1.86; р=0.011), and early AF recurrence (RR 7.57; 95 % CI 3.84-14.90; р<0.001).Conclusion      Common PV collector and multiple ineffective AADs are risk factors of ineffective CBA. Early recurrences during the first 3 postoperative months are a significant risk factor of long-term AF recurrences.

[Pulmonary embolism and diffuse alveolar bleeding: combination options and therapy features].

The analysis of the mechanisms of the formation of a rare clinical combination of pulmonary embolism (PE) and diffuse alveolar hemorrhage (DAH), which are complications of systemic vasculitis associated with antibodies to the cytoplasm of neutrophils (primarily granulomatosis with polyangiitis), systemic lupus erythematosus and secondary antiphlogistic syndrome primary antiphospholipid syndrome and Goodpastures syndrome. Taking into account the chronological sequence of the occurrence of PE and DAH, 3 variants of the onset of these potentially fatal additions to the underlying disease were considered: the anticipatory DAH development of PE, delayed from DAH PE and joint (within 24 hours) formation of PE and DAH. A review of single descriptions of such a combination of complications of granulomatosis with polyangiitis is carried out, criteria are indicated, a working classification of severity is given and, taking this into account, a modern program of therapy for DAH as an independent event and in combination with PE.

The alternative complement pathway in ANCA-associated vasculitis: further evidence and a meta-analysis.

We compared the common pathway components C3a, C5a and membrane attack complex (MAC), also known as C5b-9, and the alternative pathway components factor B and properdin in patients with ANCA-associated vasculitis (AAV) and healthy controls, and conducted a meta-analysis of the available clinical evidence for the role of complement activation in the pathogenesis of AAV. Complement components were evaluated in 59 patients with newly diagnosed or relapsing granulomatosis with polyangiitis or microscopic polyangiitis and 36 healthy volunteers. In 28 patients, testing was repeated in remission. Next, we performed a meta-analysis by searching databases to identify studies comparing complement levels in AAV patients and controls. A random-effects model was used for statistical analyses. The median concentrations of MAC, C5a, C3a and factor B were higher in active AAV patients (P < 0·001). Achievement of remission was associated with reductions in C3a (P = 0·005), C5a (P = 0·035) and factor B levels (P = 0·045), whereas MAC and properdin levels did not change. In active AAV, there were no effects of ANCA specificity, disease phenotype, previous immunosuppression or disease severity on complement levels. A total of 1122 articles were screened, and five studies, including this report, were entered into the meta-analysis. Plasma MAC, C5a and factor B in patients with active AAV were increased compared to patients in remission (excluding factor B) and controls. Changes in C3a were of borderline significance. Our findings and the results of the meta-analysis support activation of the complement system predominantly via the alternative pathway in AAV patients.

[Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids]. / Khronicheskoe limfotsitarnoe vospalenie s perivaskulyarnym nakopleniem kontrastnogo veshchestva v mostu golovnogo mozga, otvechayushchee na lechenie steroidami.

Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is an inflammatory disease of the central nervous system, mainly affecting the brain stem, cerebellum and spinal cord. The clinical picture includes gradually developing ataxia, double vision, dysarthria, pyramidal and cognitive impairment. Morphological examination reveals T-cell perivascular lymphocytic infiltration with CD4 lymphocytes predominance over CD8 lymphocytes. The cause of the disease is unknown. The article describes two patients (a 18-year-old woman and a 40-year-old man) with typical clinical and MRI manifestations of CLIPPERS, which was confirmed by brain biopsy in the female patient. The duration of follow-up was 3 and 7 years, respectively. Both patients survived an infection 2-3 weeks before the onset of disease that allows one to discuss its role in CLIPPERS pathogenesis. Both patients had a clear clinical and MRI responsiveness to steroids. In the female patient, steroids were replaced by intramuscular administration of the TNF-α blocker adalimumab. During 1,5 years of its use, there were no clinical relapses and pathological brain changes on MRI.

[Clinicopatological variants and risk factors for chronic kidney disease in rheumatoid arthritis].

Recent studies have shown a high risk of chronic kidney disease and associated cardiovascular complications in patients with rheumatoid arthritis (RA), which determines the prognosis. However, the prevalence of chronic kidney disease (CKD) in RA has not been established in the Russians. AIM: Study was to examine the prevalence, risk factors and histological variants of CKD in RA. MATERIALS AND METHODS: 180 patients with rheumatoid arthritis were observed in the Tareev clinic of nephrology, for the period from 2014 to 2019 years. Age, gender, duration of RA, drug therapy, ESR, CRP, DAS28, renal function, proteinuria, histological variants were analyzed. Of the common population risk factors for CKD arterial hypertension, weight index, serum lipids and glucose levels were also assessed. RESULTS: The prevalence of CKD in RA was 19.7%. Age, presence and stage of arterial hypertension, an increase in body mass index, as well as high rates of disease activity ESR, CRP, DAS28 score and duration of RA were risk factors of CKD in RA. Age, duration of the disease, stage of AH and hypercholesterolemia were risk factors in multifactorial regression analysis. Amyloidosis was the most common histologic pattern (50.0%), followed by chronic glomerulonephritis (30.4%) and tubulo-interstitial nephritis (19.6%). Among chronic glomerulonephritis mesangial glomerulonephritis was the most frequent. Renal amyloidosis was associated with a duration of RA, presence of systemic symptoms and CRP level. An isolated decrease in GFR of less than 60 ml/min was detected in 31 (36.0%) out of 86 patients. Сonclusion. The risk factors for CKD in patients with RA are activity and duration of the disease In addition to common population factors. Amyloidosis was the most common histologic pattern associated with duration of RA and inflammatory proteins levels.

[IgG4-associated disease in differential diagnosis of inflammatory orbitopathy].

IgG4-associated disease (IgG4-RD) is a systemic inflammatory disease characterized by tumorlike sclerosing masses in different organs. Differential diagnosis in orbital IgG4-RD includes majority of conditions, such as thyroid eye disease (TED), sarcoidosis, granulomatosis with polyangiitis, idiopatic orbital inflammation, limphoproliferative diseases and others. A case of IgG4-RD with different organs involvement and complicated differential diagnosis is presented. This case demonstrates very uncommon manifestation of IgG4-RD, when orbital involvement was very similar with TED. Systemic process was not recognized during a long period of time and diagnosis of IgG4-RD was established only after biopsy of abnormally increased lacrimal gland. Differential diagnosis included other systemic diseases, first of all sarcoidosis, GPA, and lymphoma. Biopsy results were consistent with the gold standard of diagnosis, e. g. more than 40% of plasma cells were IgG4 positive. This case demonstrates the necessity of orbital biopsy before starting immunosuppression to avoid inappropriate treatment strategy.

[Atrial myocarditis in a patient with Takayasu arteritis].

Takayasu arteritis belongs to the group of systemic vasculitis with a predominant lesion of large - caliber vessels and the development of stenosis of their lumen. In world practice, to establish the diagnosis of arteritis Takayasu apply the criteria proposed by the American College of rheumatologists. Currently, there are no randomized clinical trials related to the disease, and the diagnosis and treatment of patients are based on a number of small studies, a series of clinical cases and expert opinion. The described clinical observation of a patient with Takayasu arteritis is of interest in connection with the detected atrial myocarditis during MRI diagnosis of the heart with contrast, which allows us to discuss the feasibility of this imaging technique in complex and doubtful cases.

[Clinical manifestations of orbital lesion in granulomatosis with polyangiitis]. / Klinicheskie proiavleniia porazheniia orbity pri granulematoze s poliangiitom.

One of the most common and potentially threatening manifestations of granulomatosis with polyangiitis (GPA) is orbital lesion. PURPOSE: To study the clinical course and prognosis of orbital lesions of various localization in GPA patients. Material and me-thods. The study included 226 patients with GPA, 74 of them with orbital lesion. Ophthalmic examination consisted of visual acuity test, biomicroscopy, ophthalmoscopy, exophthalmometry and ocular mobility test. Visualization was done using multislice computed tomography and/or magnetic resonance tomography and/or ultrasound examination. RESULTS: Among the patients of the study group, in 35.1% the lesion was limited to dacryoadenitis, in 4.0% of patients - to myositis, and 70.8% had extensive inflammatory orbital masses. Patients with orbital masses had systemic disease in 51.1%, compared to 7.7% in dacryoadenitis (p=0.00). Clinical progression in patients with orbital masses was characterized by severe exophthalmos, periorbital swelling and hyperemia. Patients with dacryoadenitis, on the contrary, had only mild symptoms. Patients with orbital masses had unfavorable prognosis. There were only three patients with myositis in the study group, so the data on them is limited; their clinical symptoms included light periorbital swelling, exophthalmos, strabismus, painful binocular diplopia and eye movement restriction. The disease was recurring in two cases. CONCLUSION: Patients with orbital involvement in GPA may have different course of the disease depending on the localization of inflammation.

[Essential cryoglobulinemic vasculitis with the development of mesenteric vascular thrombosis and intestinal gangrene]. / Éssentsial'nyi krioglobulinemicheskii vaskulit s razvitiem tromboza mezenterial'nykh sosudov i gangreny kishki.

The paper describes a case of essential cryoglobulinemia unassociated with hepatitis B and C viruses. The morphological substrate of the disease was exclusively proliferative endothrombovasculitis without destructive changes in the walls of affected vessels. In addition, in the late stage of the disease, there was its unusual manifestation associated with inflammation of the mesentery arteriolar walls and with the formation of occlusive blood clots in their lumens, which led to severe abdominal diseases. The female patient showed a mosaic involvement of the loops of the bowel in the necrotic process as its separate segments, which was associated with damage to a large number of small vessels. The feature of the case is a set of 4 risk factors for a fatal disease outcome, such as age over 65 years, pulmonary, renal, and intestinal lesions.

Clinical features of different orbital manifestations of granulomatosis with polyangiitis.

PURPOSE: The aim of this study was to distinguish different forms of orbital involvement in granulomatosis with polyangiitis (GPA) and to compare their clinical course and outcomes. METHODS: Two hundred twenty-six consecutive patients with GPA were retrospectively studied. All patients fulfilled the classification criteria of American College of Rheumatology; diagnosis of localized GPA was established according to Chapel Hill Consensus. Of those, 74 patients with orbital disease were enrolled into further investigation of different forms of orbital disease. RESULTS: Overall ocular involvement was diagnosed in 50% (113/226) of patients; in 5.3% (12/226), inflammatory eye disease resulted in permanent visual loss. Most common ophthalmic manifestations were orbital masses, episcleritis/conjunctivitis, and scleritis (74/226, 32/226, and 12/226, respectively). Seventy-four patients with orbital involvement were divided into three groups: those with orbital mass without primary lacrimal gland involvement (1st group, 45 patients), those with lacrimal gland involvement (2nd group, 26 patients), and those with extraocular myositis (3rd group, 3 patients). Symptoms such as orbital pain, decreased vision, double vision, red eye, scleritis, orbital wall destruction, primary gaze strabismus, and ocular motility restriction were significantly more common in the 1st group. Peripheral ulcerative keratitis (PUK) was present in the 1st group only. Patients of the 1st group suffered from visual loss, double vision, primary gaze strabismus, and ocular motility restriction significantly more often. Eleven of them developed visual loss; 5 of them underwent enucleation, whereas in the group of patients with dacryoadenitis, only 1 patient had BCVA less than 0.3. CONCLUSIONS: Three types of orbital disease in GPA were proposed: orbital mass without primary lacrimal gland involvement, dacryoadenitis, and extraocular myositis. Patients with orbital mass without lacrimal gland involvement are characterized with a higher rate of systemic disease, severe clinical course not uncommonly associated with other ophthalmic manifestations (necrotizing scleritis, PUK, orbital walls destruction), relatively unfavorable outcome with high level of morbidity (optic nerve atrophy, anophthalmos, strabismus), and higher rate of recurrences. Dacryoadenitis in GPA showed to be not severe manifestation with favorable prognosis.

Relationship between serologic profile (ANCA type) and clinical features of renal involvement in ANCA-associated vasculitides.

AIM: To compare the frequency, clinical features and outcomes of renal involvement in ANCA-associated vasculitides (AAV) in patients with antibodies against proteinase-3 (pr3-ANCA) and myeloperoxidase (MPO-ANCA). MATERIALS AND METHODS: In our retrospective study we enrolled 264 patients, 94 males and 170 females, median age 53 [36; 62] years. Among them 157 were pr3-ANCA positive and 107 were MPO-ANCA positive. AAV was diagnosed according to ACR criteria and Chapel Hill consensus conference definition (2012). Median follow up was 44 [18; 93] months. We assessed baseline BVAS and VDI by the end of the follow up. Serum creatinine (sCr), estimated glomerular filtration rate (eGFR), hematuria and daily proteinuria were estimated. Diagnosis and stage of chronic kidney disease (CKD) and acute kidney injury (AKI) were established according to KDIGO guidelines (2012) and Scientific Society of Russian Nephrologists (2016). RESULTS: Renal involvement was present in 181 (68.6%) patients, and its frequency was similar in pr3-ANCA and MPO-ANCA subgroups. Patients with MPO-ANCA developed rapidly progressive glomerulonephritis and hypertension significantly more often than patients with pr3-ANCA: 50.7% vs 35.6% (p=0.049) and 46.1% vs 29.8% (p=0.029) respectively. At disease onset, median sCr was significantly higher and eGFR was significantly lower in patients with MPO-ANCA (p<0.05). 1-year and 5-year renal survival rates were similar in pr3-ANCA-positive (93.9% and 87.4% respectively) and MPO-ANCA positive patients (87.4% and 83.1% respectively). Median BVAS and VDI scores were significantly higher in pr3-ANCA subgroup. The number of patients who developed AAV relapse during 1-year follow up was also significantly higher in pr3-ANCA subgroup. The frequency of eye and ENT involvement was significantly higher in pr3-ANCA positive patients than in MPO-ANCA-positive patients. CONCLUSION: The frequency of extrarenal manifestations, clinical features of renal involvement and relapse rate are associated with AAV serotype.

Clinical features of kidney involvement in microscopic microscopic polyangiitis.

AIM: To evaluate clinical features and outcomes of renal involvement in patients with microscopic polyangiitis (MPA). MATERIALS AND METHODS: We enrolled 99 patients with MPA, diagnosed in accordance with the algorithm of the European Medicines Evaluation Agency (EMEA) and the Chapel Hill consensus conference definition (2012). Serum creatinine (sCr), estimated glomerular filtration rate (eGFR), hematuria and proteinuria were estimated. Frequency of rapidly progressive renal failure (a twofold increase in the sCr level in ≤3 months) was regarded as the clinical equivalent of rapidly progressive glomerulonephritis (RPGN). RESULTS: Renal involvement was present in 92 (92.9%) patients. RPGN developed in 51 (55,4%) patients. The most common features of kidney involvement were hematuria and subnephrotic proteinuria. Arterial hypertension was revealed in 32 (34.7%) patients and was associated with RPGN (p<0.004). End-stage renal disease (ESRD) developed in 11 (11.9%) patients. Despite effective induction therapy disease relapses occurred in 20 (21.1%) patients during the 1st year, including renal relapses in 12 (13.3%) cases. During 5-year follow up 34 (37.1%) patients developed disease relapses, including renal relapses in 22 (24.4%) patients. CONCLUSION: Renal involvement is one of the most common manifestations of MPA with a high frequency of RPGN. More than one third of patients develop disease relapses despite adequate therapy.

The modern therapy of systemic vasculitides: perspectives and challenges.

Systemic vasculitis is a heterogeneous group of inflammatory diseases, which are classified according to the diameter of the affected vessels. The treatment of systemic vasculitis is no longer empirical, because of increasing number of randomized clinical trials in this field. In recent years, there was a trend to limit the cumulative dose of glucocorticosteroids and immunosuppressive drugs, partially through biological drugs usage. However, biologic therapy is not always superior to combination of glucocorticosteroids and cytotoxic drugs. The efficacy of different biologic drugs varies in patients with different forms of systemic vasculitis, which creates the ground for personalized therapy of these diseases. Another serious problem is the absence of strict criteria to immunosuppressive therapy intensification, especially in vasculitis, affecting large vessels, due to the lack of reliable laboratory markers of disease activity. The article reviews modern approaches to the treatment of some types of systemic vasculitis, including ANCA-associated vasculitides, giant cell arteritis, Takayasu`s arteritis and cryoglobulinemic vasculitis.

[Giant cell arteritis: Genetic and epigenetic aspects]. / Gigantokletochnyi arteriit: geneticheskie i épigeneticheskie aspekty.

The paper describes clinical cases in 2 patients (brothers) with giant cell arteritis. It analyzes the genetic and epigenetic aspects of the disease. The data available in the Russian and foreign literature are given.

[Kidney injury molecules (KIM-1, MCP-1) and type IV collagen in the assessment of activity of antineutrophil cytoplasmic antibody-associated glomerulonephritis]. / Molekuly povrezhdeniia pochechnoi tkani (KIM-1, MCP-1) i kollagen IV tipa v otsenke aktivnosti assotsiirovannogo s antineitrofil'nymi tsitoplazmaticheskimi antitelami glomerulonefrita.

AIM: To assess the significance of determining the serum and urinary concentrations of monocyte chemotactic protein-1 (MCP-1), kidney injury molecule-1 (KIM-1), and type IV collagen in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) to estimate the activity of renal involvement in AAV. SUBJECTS AND METHODS: 78 patients (32 men and 46 women) (median age 55 (45; 61) years) with AAV were examined. The patients were divided into 3 groups according to the AAV activity estimated using the Birmingham vasculitis activity Score (BVAS): 1) 25 patients with active ANCA-associated glomerulonephritis (GN); 2) 26 patients with active AAV without renal involvement; 3) 27 patients in sustained AAV remission. The serum and urinary concentrations of the markers were measured by enzyme immunoassay. RESULTS: The urinary concentration of all 3 biomarkers was higher in patients with renal involvement (Group 1); the differences in the levels of MCP-1 and type IV collagen were statistically significant as compared to Groups 2 and 3 (p<0.01), while that in KIM-1 level was only in Group 2. There were statistically significant correlations between the urinary concentration of these biomarkers and the traditional GN activity indices (erythrocyturia, daily proteinuria (DPU), total BVAS scores that reflect renal involvement, as well as serum creatinine levels and estimated glomerular filtration rate (p<0.05). ROC curve analysis showed that the urinary MCP-1 excretion of ≥159 pg/ml had the highest (92%) sensitivity and urinary type IV collagen excretion of ≥3.09 µg/l had the highest (86%) specificity in assessing the activity of ANCA-associated GN. At the same time, their diagnostic value increased in terms of a combination of DPU and ESR (96% sensitivity, 84.9% specificity). CONCLUSION: The urinary excretion of MCP-1, KIM-1, and type IV collagen reflects the severity of local renal inflammation in AAV patients and a study of these indicators is a promising diagnostic tool for assessing the activity of ANCA-associated GN.