nefrНефрологияNephrology (Saint-Petersburg)1561-62742541-9439Pavlov First Saint-Petersburg State Medical University10.36485/1561-6274-2019-236-45-60nefr-1769Research ArticleОРИГИНАЛЬНЫЕ СТАТЬИ. КЛИНИЧЕСКИЕ ИССЛЕДОВАНИЯORIGINAL ARTICLES. CLINICAL INVESTIGATIONSИммуноглобулин А-нефропатия в российской популяции: клинико-морфологическая презентация и отдаленный прогнозImmunoglobulin A-nephropathy in Russian population: clinical and morphological presentation and long-term prognosishttps://orcid.org/0000-0002-7179-5520ДобронравовВ. А.DobronravovV. A.

Добронравов Владимир Александрович, профессор, доктор медицинских наук  Первый Санкт-Петербургский государственный медицинский университет им. акад. И.П. Павлова, заместитель директора Научно-исследовательского института нефрологии по научной работе, профессор кафедры пропедевтики внутренних болезней с клиникой

197022, Санкт-Петербург, ул. Л. Толстого, дом 17, корп. 54

 

Vladimir A. Dobronravov, Prof. , MD, PhD, DMedSci Pavlov First Saint Petersburg State Medical University, Research Institute of Nephrology, Vice-Director, Department of Propedeutics of Internal Diseases, professor

197022, St. Petersburg, L. Tolstoy st., 17, build 54

 

dobronravov@nephrolog.ruМужецкаяТ. О.MuzhetskayaT. O.

Мужецкая Татьяна Олеговна, Первый Санкт-Петербургский государственный медицинский университет им. акад. И.П. Павлова, Научно-исследовательский институт нефрологии, врач-нефролог

197022, Санкт-Петербург, ул. Л. Толстого, дом 17, корп. 54

 

Tatyana O. Muzheckaya, MD Pavlov First Saint Petersburg State Medical University, Research Institute of Nephrology, nephrologist

197022, St. Petersburg, L. Tolstoy st., 17, build 54

tatyana.muzheckaya@gmail.comЛинД. И.LinD. I.

Лин Дарья, лечебный факультет, студентка VI курса

197022, Санкт-Петербург, ул. Л. Толстого, д. 6/8

Daria I. Lin, student, Faculty of Medicine, 6-year student

197022, St. Petersburg, L. Tolstoy st., 6/8

daryaspb1904@gmail.comКочоянЗ. Ш.KochoyanZ. Sh.

Кочоян Зинаида Шакроевна, лечебный факультет, студентка VI курса

197022, Санкт-Петербург, ул. Л. Толстого, д. 6/8

Zinaida Sh. Kochoyan, student, Faculty of Medicine, 6-year student

197022, St. Petersburg, L. Tolstoy st., 6/8

zinshak@gmail.comНаучно-исследовательский институт нефрологииРоссияResearch Institute of NephrologyRussian FederationПервого Санкт-Петербургского государственного медицинского университета им. акад. И.П. ПавловаРоссияPavlov First Saint-Petersburg State Medical UniversityRussian Federation2019251220192364560Copyright © Добронравов В.А., Мужецкая Т.О., Лин Д.И., Кочоян З.Ш., 20192019Добронравов В.А., Мужецкая Т.О., Лин Д.И., Кочоян З.Ш.Dobronravov V.A., Muzhetskaya T.O., Lin D.I., Kochoyan Z.S.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://journal.nephrolog.ru/jour/article/view/1769ЦЕЛЬ ИССЛЕДОВАНИЯ

ЦЕЛЬ ИССЛЕДОВАНИЯ. Определение особенностей распространенности, клинических и морфологических проявлений, а также прогноза IgA-нефропатии в российской популяции.

ПАЦИЕНТЫ И МЕТОДЫ

ПАЦИЕНТЫ И МЕТОДЫ. В ретроспективное исследование были включены случаи с диагнозом первичной IgAнефропатии (IgAN) (возраст 34±12 лет, мужчин – 55 %) В исследовании использовали демографические и клинические показатели, данные светооптического и иммуноморфологического исследований, сведения о лечении. Регистрировали следующие исходы: наступление полной (ПР) или частичной ремиссии (ЧР), смерть от всех причин, необходимость заместительной почечной терапии (ЗПТ), снижение рСКФ<15 мл/мин/1,73 м2, снижение рСКФ ≥ 50 % от исходной. Оценку прогрессирования болезни и ассоциированных факторов проводили по композитной конечной точке, которая включала все три почечных исхода. РЕЗУЛЬТАТЫ. Средняя за период исследования частота новых случаев IgAN среди всех индикационных биопсий и морфологически подтвержденных первичных иммунных гломерулопатий составила 20,5 и 31,7 % соответственно (с 2014 по 2019 г. – 23,2 и 41,5 %). На момент биопсии почки суточная протеинурия (СП) была 2,20 (1,10;4,40) г, рСКФ – 69±32 мл/мин/1,73 м2. Артериальную гипертензию и снижение рСКФ <60 мл/мин/1,73 м2 отмечали в 75 и 36 % случаев соответственно. Распространенность гистологических изменений в соответствии с MEST-C классификацией была следующей: M1 – 40,5 %, E1 – 22,9 %, S1 – 70,2 %, T1 – 22 %, T2 – 9 %, С1 – 16,7 %, С2 – 4,4 %. Чаще находили сочетанные депозиты IgA и IgM (71,1 % случаев), реже – IgA и IgG (9,6 %). В периоде наблюдения зарегистрировано 6 смертей от всех причин (1,7 %). Кумулятивная доля не нуждавшихся в диализе случаев к 10 годам наблюдения составила 72 %, а случаев, не достигших композитной конечной точки прогноза, – 55 %. ПР зарегистрированы в 26 % случаев, ЧР – в 24 %. ПР/ЧР чаще наблюдали у пациентов, получивших иммуносупрессивную терапию в сравнении с больными на симптоматической терапии (60 % vs. 40 %, р=0,001), в том числе ЧР (31 и 16 %) и ПР (29 и 24 %). Независимыми факторами, связанными с негативным прогнозом, оказались: мужской пол, более молодой возраст, повышение среднего АД, снижение рСКФ, более выраженные гематурия, фиброз интерстиция/атрофия канальцев (≥50 %), перитубулярный капиллярит и наличие любых полулуний. В сравнении с когортами другой этнической или географической принадлежности анализируемую группу случаев IgAN отличали более выраженные клинико-морфологические проявления и более быстрое прогрессирование болезни.

ЗАКЛЮЧЕНИЕ

ЗАКЛЮЧЕНИЕ. В российской популяции IgAN является наиболее распространенной гломерулопатией с выраженными клинико-морфологическими проявлениями болезни на момент диагностики и неблагоприятным прогнозом.

 AIM

 AIM. The analysis of incidence, clinical and morphological manifestations, and the prognosis of IgA nephropathy in the Russian population.

PATIENTS AND METHODS

PATIENTS AND METHODS. Six hundred cases with primary IgA nephropathy (IgAN) from 1999 to 2019 were enrolled in the single-center retrospective study. Demographic and clinical parameters, morphrology data, and the treatment were analyzed. Three hundred forty seven patients were included in follow-up study. The following outcomes were evaluated: the occurrence of complete (PR) or partial remission (CR), death from all causes, the need for renal replacement therapy (RRT). The composite endpoint (RRT or eGFR decrease ≥ 50 % from the time of biopsy) was used to evaluate the risk of IgAN progression and associated factors.

RESULTS

RESULTS. The period-average incidence of IgAN cases was 20.5 % of all indication biopsies and 31.7 % of primary immune glomerulopathies (with gradual increase to 41,5 % in last 5 years). At the time of the kidney biopsy, the proteinuria was 2.20 (1.10; 4.40) g/24h, eGFR – 69 ± 32 ml / min / 1.73 m2. Proportions of cases with arterial hypertension and with eGFR <60 ml / min / 1.73 m2 were 75 % and 36 %, respectively. The prevalence of histological changes in accordance with the MEST-C classification was as follows: M1 – 40.5 %, E1 -22.9 %, S1-70.2 %, T1-22 %, T2 – 9 %, C1-16.7 %, C2 – 4.4 %. Combined deposits of IgA and IgM (71.1 % of cases) were more frequent compared to IgA and IgG (9,6 %). In the followup period (27 (11; 61) month), 6 deaths from all causes were registered (1.7 %). The 10-year cumulative renal survival was 75 % (by dialysis) and 55 % (by composite endpoint). PR registered in 26 % of cases, CR – 24 %. PR / CR was more frequent in patients who received immunosuppression compared with patients on renin-angiotensin system blockers only (60 % vs. 40 %, p = 0.001). In multivariable Cox regression the independent factors associated with the risk of IgAN progression were: male gender, a younger age, higher blood pressure and hematuria, lower eGFR, interstitial fibrosis/ tubular atrophy (≥50 %), peritubular capillaritis and the presence of any crescents. Compared to the cohorts of other ethnic or geographical affiliation, analyzed IgAN cases were found to have more severe clinical and morphological presentations and faster progression rate.

CONCLUSION

CONCLUSION. While being the most common glomerulopathy, IgAN in the Russian population has more pronounced clinical and morphological presentations and an unfavorable prognosis.

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The authors declare that there are no conflicts of interest present.