MO696: Characteristics and Survival Results of Peritoneal Dialysis Patients Suffering from Covid-19 in Turkey: A Multicenter National Study

BACKGROUND AND AIMS

Although existing data suggest an increased mortality rate, data about the course of coronavirus disease 2019 (COVID-19) in peritoneal dialysis (PD) patients, its short- and long-term effects on the patient and technique survival are limited. Moreover, specific factors associated with increased risk of death have not been clearly defined yet. Therefore, we aimed to study the characteristics of PD patients with COVID-19, determine the short-term mortality and other medical complications, and delineate the factors associated with COVID-19 outcome.

METHOD

This national multicenter study included all PD patients who had confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection based on positive reverse transcriptase–polymerase chain reaction testing of a nasopharyngeal swab recorded in this database from the attending 27 PD centers. The demographic data, comorbidities, medications used, PD-related data were recorded as well as clinical, laboratory and radiological findings of COVID-19 and outcomes at the end of the first month were recorded.

RESULTS

We enrolled 142 COVID-19 patients (median age: 52 years). A total of 58.2% of patients had mild disease at diagnosis, lung involvement was detected in 60.8% of patients. A total of 83 (58.4%) patients were hospitalized, 31 (21.8%) patients were admitted to intensive care unit and 24 needed mechanical ventilation. A total of 15 (10.5%) patients were switched to hemodialysis and hemodiafiltration was performed for 4 (2.8%) patients. Persisting pulmonary symptoms (n = 27), lower respiratory system infection (n = 12), rehospitalization for any reason (n = 24), malnutrition (n = 6), hypervolemia (n = 13), peritonitis (n = 7), ultrafiltration failure (n = 7) and in PD modality change (n = 8) were reported in survivors. During the 1 month from the diagnosis of COVID-19, 26 patients (18.31%) died. The non-survivor group was older and comorbidities were more prevalent. Fever, dyspnea, cough, serious-vital disease at presentation, bilateral pulmonary involvement and pleural effusion were more frequent among non-survivors. Age (OR:1.102; 95% CI: 1.032–1.117; P:0.004), moderate–severe clinical disease at presentation (OR:26.825; 95% CI: 4.578–157.172; P < 0.001) and CRP levels (OR:1.008; 95% CI; 1.000–1.016; P:0.040) were associated with increased first-month mortality in multivariate analysis.

CONCLUSION

Early mortality rate and medical complications are quite high in PD patients with COVID-19. Age, clinical severity of COVID-19 and baseline CRP level are the independent parameters associated with mortality.

Characteristics and outcomes of acute kidney injury in hospitalized COVID-19 patients: A multicenter study by the Turkish society of nephrology

BACKGROUND

Acute kidney injury (AKI) is common in coronavirus disease-2019 (COVID-19) and the severity of AKI is linked to adverse outcomes. In this study, we investigated the factors associated with in-hospital outcomes among hospitalized patients with COVID-19 and AKI.

METHODS

In this multicenter retrospective observational study, we evaluated the characteristics and in-hospital renal and patient outcomes of 578 patients with confirmed COVID-19 and AKI. Data were collected from 34 hospitals in Turkey from March 11 to June 30, 2020. AKI definition and staging were based on the Kidney Disease Improving Global Outcomes criteria. Patients with end-stage kidney disease or with a kidney transplant were excluded. Renal outcomes were identified only in discharged patients.

RESULTS

The median age of the patients was 69 years, and 60.9% were males. The most frequent comorbid conditions were hypertension (70.5%), diabetes mellitus (43.8%), and chronic kidney disease (CKD) (37.6%). The proportions of AKI stages 1, 2, and 3 were 54.0%, 24.7%, and 21.3%, respectively. 291 patients (50.3%) were admitted to the intensive care unit. Renal improvement was complete in 81.7% and partial in 17.2% of the patients who were discharged. Renal outcomes were worse in patients with AKI stage 3 or baseline CKD. The overall in-hospital mortality in patients with AKI was 38.9%. In-hospital mortality rate was not different in patients with preexisting non-dialysis CKD compared to patients without CKD (34.4 versus 34.0%, p = 0.924). By multivariate Cox regression analysis, age (hazard ratio [HR] [95% confidence interval (95%CI)]: 1.01 [1.0-1.03], p = 0.035], male gender (HR [95%CI]: 1.47 [1.04-2.09], p = 0.029), diabetes mellitus (HR [95%CI]: 1.51 [1.06-2.17], p = 0.022) and cerebrovascular disease (HR [95%CI]: 1.82 [1.08-3.07], p = 0.023), serum lactate dehydrogenase (greater than two-fold increase) (HR [95%CI]: 1.55 [1.05-2.30], p = 0.027) and AKI stage 2 (HR [95%CI]: 1.98 [1.25-3.14], p = 0.003) and stage 3 (HR [95%CI]: 2.25 [1.44-3.51], p = 0.0001) were independent predictors of in-hospital mortality.

CONCLUSIONS

Advanced-stage AKI is associated with extremely high mortality among hospitalized COVID-19 patients. Age, male gender, comorbidities, which are risk factors for mortality in patients with COVID-19 in the general population, are also related to in-hospital mortality in patients with AKI. However, preexisting non-dialysis CKD did not increase in-hospital mortality rate among AKI patients. Renal problems continue in a significant portion of the patients who were discharged.

MO357ACUTE KIDNEY INJURY IN HOSPITALIZED COVID-19 PATIENTS: A MULTICENTRE STUDY BY TURKISH SOCIETY OF NEPHROLOGY

Background and Aims

Acute kidney injury (AKI) is common in coronavirus disease-2019 (COVID-19) and the severity of AKI is linked to adverse outcomes. In this study, we investigated the factors associated with in-hospital outcomes among hospitalized patients with COVID-19 and AKI.

Method

In this multicenter retrospective observational study, we evaluated the characteristics and in-hospital renal and patient outcomes of 578 patients with confirmed COVID-19 and AKI. Data were collected from 34 hospitals in Turkey from March 11 to June 30, 2020. AKI definition and staging were based on the Kidney Disease Improving Global Outcomes criteria. Patients with end-stage kidney disease or with a kidney transplant were excluded. Renal outcomes were identified only in discharged patients.

Results

The median age of the patients was 69 years, and 60.9% were males. The most frequent comorbid conditions were hypertension (70.5%), diabetes mellitus (43.8%), and chronic kidney disease (41.5%). The proportions of AKI stages 1, 2, and 3 were 54.0%, 24.7%, and 21.3%, respectively. 291 patients (50.3%) were admitted to the intensive care unit. Renal improvement was complete in 80.7% and partial in 17% of the patients who were discharged. Renal outcomes were worse in patients with AKI stage 3 or baseline CKD. The overall in-hospital mortality in patients with AKI was 38.9%. By multivariate Cox regression analysis, age (hazard ratio [HR] [95% confidence interval (95%CI)]: 1.01 [1.0-1.03], p = 0.035], male gender (HR [95%CI]: 1.47 [1.04-2.09], p = 0.029), diabetes mellitus (HR [95%CI]: 1.51 [1.06-2.17], p = 0.022) and cerebrovascular disease (HR [95%CI]: 1.82 [1.08-3.07], p = 0.023), serum lactate dehydrogenase (greater than two-fold increase) (HR [95%CI]: 1.55 [1.05-2.30], p = 0.027) and AKI stage 2 (HR [95%CI]: 1.98 [1.25-3.14], p = 0.003) and stage 3 (HR [95%CI]: 2.25 [1.44-3.51], p = 0.0001) were independent predictors of in-hospital mortality. The in-hospital mortality rates across AKI stages by age, gender, and diabetes mellitus were shown in the Figure.

Conclusion

Advanced-stage AKI is associated with extremely high mortality among hospitalized COVID-19 patients. Age, male gender, comorbidities, which are risk factors for mortality in patients with COVID-19 in the general population, are also related to in-hospital mortality in patients with AKI. Renal problems continue in a significant portion of the patients who were discharged.

Characteristics of primary glomerular diseases patients with hematuria in Turkey: the data from TSN-GOLD Working Group

PURPOSE

Hematuria is one of the most common laboratory findings in nephrology practice. To date, there is no enough data regarding the clinical and histopathologic characteristics of primary glomerular disease (PGD) patients with hematuria in our country.

METHODS

Data were obtained from national multicenter (47 centers) data entered into the Turkish Society of Nephrology Glomerular Diseases (TSN-GOLD) database between May 2009 and June 2019. The data of all PGD patients over the age of 16 years who were diagnosed with renal biopsy and had hematuria data were included in the study. Demographic characteristics, laboratory and biopsy findings were also recorded.

RESULTS

Data of 3394 PGD patients were included in the study. While 1699 (50.1%) patients had hematuria, 1695 (49.9%) patients did not have hematuria. Patients with hematuria had statistically higher systolic blood pressure, serum blood urea nitrogen, creatinine, albumin, levels and urine pyuria. However, these patients had statistically lower age, body mass index, presence of hypertension and diabetes, eGFR, 24-h proteinuria, serum total, HDL and LDL cholesterol, and C3 levels when compared with patients without hematuria. Hematuria was present 609 of 1733 patients (35.8%) among the patients presenting with nephrotic syndrome, while it was presented in 1090 of 1661 (64.2%) patients in non-nephrotics (p < 0.001).

CONCLUSION

This is the first multicenter national report regarding the demographic and histopathologic data of PGD patients with or without hematuria. Hematuria, a feature of nephritic syndrome, was found at a higher than expected in the PGDs presenting with nephrotic syndrome in our national database.

P0490IS THE SEVERITY OF GLOMERULAR IGG STAINING IN PATIENT WITH IGA NEPHROPATHY USEFUL FOR PREDICTING POOR RENAL PROGNOSIS? THE DATA FROM TSN-GOLD WORKING GROUP

Background and Aims

In IgA nephropathy (IgAN), which is characterized by mesangial IgA accumulation, there is the formation of circulating autoantibodies against galactose deficient IgA1s (Gd-IgA1). IgG / Gd-IgA1 immunocomplexes accumulate in the glomerular mesangium and play a role in the pathogenesis of IgAN. Recent studies have suggested a relationship between glomerular IgG deposition and the severity of glomerular inflammation. However, detection of the presence and severity of IgG in routine immunofluorescence microscopy (IFM) may fail. This study aims to investigate whether IgG positivity detected by IFM is associated with poor renal prognostic indicators and whether renal prognosis can be predicted according to IgG positivity.

Method

4399 patients who were enrolled between May 2009-June 2019 in database of Turkish Society of Nephrology, Glomerular Diseases Working Group (TSN-GOLD) including 44 centers were evaluated. After exclusion criteria, 994 primary IgAN patients were included in the study. Glomerular IgG negative and positive patients were compared by means of Oxford classification scores, histopathological evaluations, proteinuria, creatinine, albumin, blood pressures. IgG positive patients were divided into subgroups according to the grade of the IFM positivity. The relationship between IgG positivity and poor prognosis criteria were evaluated.

Results

Demographic and biochemical findings of glomerular IgG positive and negative patients at the time of biopsy are shown in Table 1. No difference was found between the groups. There was no difference in the demographic and biochemical findings at the time of biopsy in IgG subgroup analyses (Table 2). There was no difference between the histopathological and Oxford MEST scores of the subgroups. Glomerular IgG positivity was not associated with diastolic blood pressure, systolic blood pressure, urea, uric acid, age, eGFR, albumin, proteinuria (p&gt; 0.05 for all, r= -0.084, r= -0.102, r= -0.006, r=0.062, r= 0.014, r= -0.044, r= -0.061, r= -0.066, r= 0.150, respectively).

Conclusion

Glomerular IgG positivity detected by routine IFM in IgAN is not associated with poor renal prognostic indicators. It is difficult to predict renal prognosis by looking at the severity of IgG positivity at the baseline evaluation.

P0501THE EPIDEMIOLOGICAL FEATURES OF PIRMARY GLOMERULAR DISEASES IN TURKEY: THE MULTICENTER STUDY OF TURKISH SOCIETY OF NEPHROLOGY GLOMERULAR DISEASES (TSN-GOLD) WORKING GROUP

Background and Aims

The largest data on the epidemiology of primary glomerular diseases (PGD) are obtained from the databases of countries or centers. Here, we presented the extended results of the Primary Glomerular Diseases Study of the Turkish Society of Nephrology Glomerular Diseases (TSN-GOLD)Working Group.

Method

The data of patients who underwent renal biopsy and diagnosed as primary glomerular disease were recorded in the database prepared for the study. Between May 2009 and May 2019, a total of 4399 patients from 47 centers were evaluated. Basal data of 3875 patients were analyzed after exclusion of those lacking light microscopy and immunofluorescence findings.

Results

The mean age was 41.5 ± 14.9 years. Of the patients, 1690 were female (43.6%) and 2180 (56.3%) were male. Nephrotic syndrome was the most common biopsy indication (51.7%). This was followed by asymptomatic urinary abnormalities (18.3%) and nephritic syndrome (17.8%). The most common PGH was IgA nephropathy (25.7%), followed by membranous nephropathy (25.6%) and FSGS (21.9%). The mean total number of glomeruli per biopsy was 17 ± 10. Mean baseline systolic blood pressure was 130 ± 20 mmHg and diastolic blood pressure was 81 ± 12 mmHg. Median proteinuria was 3300 (IQR: 1467-6307) mg / day, mean serum creatinine, estimated GFR and albumin values were 1.4 ± 1.5 mg / dl, 80.7 ± 39.1 ml / min and 3.2 ± 0.9 g / dl, respectively.

Conclusion

In Turkey, the incidence of IgA nephropathy patients have become more common than membranous nephropathy among PGD patients diagnosed with renal biopsy.

P0440EPIDEMIOLOGICAL AND CLINICAL CHARACTERSTICS OF IGA NEPHROPATHY PATIENTS IN TURKEY: TSN-GOLD WORKING GROUP

Background and Aims

According to the data of the Turkish Society of Nephrology-Glomerular Diseases Working Group (TSN-GOLD Working Group), IgA nephropathy is the most common primary glomerular disease in Turkey. The purpose of this study was to investigate the epidemiological and clinical data of IgA nephropathy patients in Turkey.

Method

4399 patients with primary glomerular diseases from 47 centers who were followed up between May 2009 and May 2019 were included in the study conducted by TSN-GOLD Working Group. 524 patients were excluded due to lack of pathological data. Among the remaining patients, demographic, clinical and laboratory data of 994 patients with IgA nephropathy were analyzed.

Results

The median age of the patients was 37 (28-47) years, and 37.3% of them were female. The laboratory and clinical data at the time of diagnosis is presented in Figure-1, and biopsy indications are described in Figure-2. The median number of glomeruli was 16 (IQR: 3.5-4.3), sclerotic glomeruli was 2 (IQR: 1-5), and segmental sclerotic glomeruli was 1 (IQR: 1-2). Exudative changes, subendothelial and subepithelial deposition were present in 566 patients (56.9%), 46 patients (4.6%) and in 38 patients (3.8%), respectively. 662 (66.1%) and 611 of the patients (61.4%) had tubular atrophy and interstitial fibrosis in varying degrees, respectively. 672 (%67.6) and 416 patients (%41.9) had interstitial inflammation and vascular changes, respectively. In immunofluorescence staining, 18%, 30.1%, 4.4%, 68% of the patients had IgG, IgM, C1q and C3 positivity, respectively. Crescentic glomeruli were detected in 227 patients (3.3 ± 3.1 glomeruli). Patients with crescentic glomeruli had significantly higher proteinuria and lower eGFR than the patients without [2203 mg/day (15-26078) vs 1807 mg/day (15-29112); p=0.001; 55.3 ml/min/1.73 m2 (3.72-141.9) vs 72 ml/min/1.73 m2 (3.84-150.81); p&lt;0.001, respectively]. Oxford classification was applied to 544 patients. Endocapillary hypercellularity (E1), mesengial hypercellularity (M1), tubular atrophy and interstitial fibrosis (T1 and T2), segmental sclerosis (S1) were present in 126 (13%), 425 (42.8%), 306 (30.8%) and 325 patients (%32.7), respectively. Proteinuria levels were higher in patients with endocapillary hypertrophy, mesengial hypercellularity, tubular atrophy-interstitial fibrosis and segmental sclerosis. eGFR levels were lower in patients with endocapillary hypertrophy, tubular atrophy-interstitial fibrosis and segmental sclerosis (Figure-3).

Conclusion

In this study we found that, the most common presentation of IgA nephropathy patients in our country was asymptomatic urinary abnormalities followed by nephritic and nephrotic syndrome. Higher proteinuria and lower eGFR values in patients with crescentic glomeruli, support the adoption of crescentic lesions in the new Oxford classification (MEST-C) to predict more precise outcome of IgA nephropathy patients. The high number of patients to whom the Oxford classification was applied provided us with the opportunity to examine the clinical reflections of pathological features. Evaluation of the follow-up data of the patients will give us the possibility to reveal the effect of initial clinical and pathological features on clinical findings and renal outcome.

P0448CHARACTERISTICS OF PRIMARY GLOMERULAR DISEASE PATIENTS WITH HEMATURIA IN TURKEY: THE DATA FROM TSN-GOLD WORKING GROUP

Background and Aims

Hematuria is one of the most common laboratory findings in nephrology practice. In different regions of the world, the etiologic causes differ. To date, there is no enough data regarding the clinical and histopathologic characteristics of primary glomerular diseases (PGD) patients with hematuria in our country.

Method

Data were obtained from national multicenter (47 centers) data entered into the Turkish Society of Nephrology Glomerular Diseases (TSN-GOLD) database between May 2009 and June 2019. The data of all PGD patients over the age of 16 years who were diagnosed with renal biopsy and had hematuria data were included in the study. The biopsy samples were processed using a light microscopy and immunofluorescence examination. Demographic characteristics such as age, sex, indications for biopsy, primary glomerular diseases, comorbidities, laboratory and biopsy findings of all patients were also recorded. Hematuria was defined as the presence of at least 5 red blood cells/hpf.

Results

Data of 3394 patients were included to the study after the exclusion of patients with secondary glomerulonephritis and patients with missing biopsy findings. While 1699 (50.1%) patients had hematuria, 1695 (49.9%) patients did not have hematuria. Demographic, laboratory, and histopathological characteristics of patients with and without hematuria are given in Table. Patients with hematuria had statistically higher systolic blood pressure (SBP), serum blood urea nitrogen, creatinine, albumin, levels and urine pyuria, however, these patients had statistically lower age, body mass index, presence of hypertension and diabetes, eGFR, 24-hour proteinuria, serum total, HDL and LDL-cholesterol and C3 levels when compared with patients without hematuria. Figure depicted the etiologic causes of patients with and without hematuria. According to histopathological findings, number of global sclerotic glomeruli, cellular and fibrocellular crescents, the levels of mesangial proliferation, endocapillary proliferation, exudative changes in glomeruli, severe tubular atrophy, interstitial inflammation, subendothelial deposition, moderate and severe IgA and C3 deposition were found to be significantly higher and the levels of basal membrane thickening, interstitial fibrosis, subepithelial deposition, severe IgG staining were found to be significantly lower in patients with hematuria.

Conclusion

This is the first multicenter national report regarding the demographic and histopathologic data of PGD patients with or without hematuria. Hematuria, a feature of nephritic syndrome, was found at a higher than expected in the PGDs presenting with nephrotic syndrome in our national database.

P0389THE PREVALENCE, CLINICAL AND PATHOLOGICAL CHARACTERISTICS OF PRIMARY FOCAL SEGMENTAL GLOMERULOSCLEROSIS IN TURKISH ADULTS: THE DATA FROM TSN-GOLD ( TURKISH SOCIETY OF NEPHROLOGY GLOMERULAR DISEASES) WORKING GROUP

Background and Aims

Focal segmental glomerulosclerosis (FSGS) is one of the primary glomerulopathies which is the most common cause of end-stage renal disease among all primary glomerular diseases. In adults, nephrotic syndrome develops 10-35% due to FSGS. However, its frequency has been increasing in recent years. This study was aimed to present the data and the prevalence of primary FSGS patients in Turkey.

Method

These data were obtained from the National Multicenter (47 centers) Primary Glomerular Diseases registry system, which was entered into the Turkish Society of Nephrology Glomerular Diseases (TSN-GOLD) database between May 2009 and June 2019. The presented data in this study is cross-sectional and includes the recorded data of the patients in the hospitalization period for the kidney biopsy. These demographic, clinic and pathological data of patients were evaluated with using statistically.

Results

Of the 3875 patients enrolled in the Primary Glomerular Diseases database, 850 (21.9%) had FSGS. The mean age of the patients was 47.1 ± 13.7 and 435 (52%) of patients were male. Two hundred and eighty one (33.1%) had hypertension and 93 (11%) had diabetes. Five hundred and four patients (59.3%) were diagnosed as nephrotic syndrome. At the time of diagnosis, the mean systolic blood pressure was 13.8 ± 18.6 mm Hg and the mean diastolic blood pressure was 81.4± 11.4 mm Hg. The laboratory findings at the time of diagnosis on following; serum creatinine 1.2 ± 0.04 mg / dl, albumin 3.3 ± 0.03 g / dl, and 24 hours urinary proteinuria amounts to 4743 ± 181 mg / day. Demographical and clinical data of the patients at the time of diagnosis were presented on Table 1. In pathological examination; the mean number of glomeruli was 16.8 ± 0.3, global sclerotic glomeruli were 3.1 ± 0.1, and segmental sclerotic glomeruli were 2.4 ± 0.1. Summary of Pathological Findings were presented on Table 2

Conclusion

It is very difficult to determine the absolute incidence and prevalence of primary FSGS. Incidence rates have been reported to range from 0.2 to 1.8 / 100,000 per year in the literature. In a United States study, the most common diagnosis in 2501 kidney biopsies was FSGS (35.9%). According to this database, the prevalence of FSGS in primary glomerular diseases in our country is 21.9%.

P0431TRENDS OF PRIMARY GLOMERULAR DISEASE IN TURKEY FROM 2009 TO 2017: A REGIONAL REGISTRY REPORT FROM TSN-GOLD WORKING GROUP

Background and Aims

Several glomerular disease registries in Europe, and they shared their data; however, there was a lack of current data on trends of primary glomerulopathy in Turkey. Glomerular disease patterns can change geographical areas and populations decade by decade. Our aim is to present Turkey's primary glomerular disease pattern from 2009 to 2017.

Method

3878 native kidney biopsy records were assessed in the Turkish Society of Nephrology Glomerulopathy (TSN-GOLD) Working Group Registry. Secondary disease (lupus, etc.) and transplant biopsies do not enroll in the registry. These records divided into four periods, before 2009, 2009 to 2013, 2013 to 2017, and 2017 to current.

Results

A total of 3858 patients (M = 2173, K = 1685) were examined. There was no difference in the distribution of number of patients according to periods (Q1 = 968, Q2 = 960, Q3 = 968, Q4 = 962). Nephrotic syndrome was the most common biopsy indication in all quarters (58.6%, 53%, 44.1%, 51.6%, respectively). Glomerulopathy types; Membranous GN (29.9%, n = 290) was the first in Q1 and IgA nephropathy (17.7%, n = 172) was the second. IgA nephropathy (28.5%, n = 274) was the most common glomerulopathy in Q2, while Membranous GN (25.5%, n = 245) was the second most common. IgA nephropathy (29.9%, n = 285) was the most common glomerulopathy in Q3, followed by FSGS (22.9%, n = 222) and Membranous GN. In Q4, FSGS (26.8, n = 258) was the most common glomerulopathy, followed by IgA nephropathy (26.7%, n = 257) and Membranous GN (24.5%, n = 236) (Figure 1).

Conclusion

While biopsy indications did not change over the years, the incidence of FSGS and IgA nephropathy gradually increased.

P0395DEMOGRAPHIC AND CLINICAL CHARACTERISTICS OF RAPIDLY PROGRESSIVE GLOMERULONEPHRITIS IN TURKEY

Background and Aims

Rapidly progressive glomerulonephritis (RPGN) is a clinical condition that develops due to different etiologic causes, characterized by a rapid and progressive decrease in renal function and progresses to end-stage renal failure in weeks to months if not treated. In our study, diagnostic and demographic characteristics of patients diagnosed with RPGN by biopsy, clinical and laboratory findings in our country were investigated.

Method

Data were obtained from national multicenter (47 centers) data entered into the Turkish Society of Nephrology Glomerular Diseases (TSN-GOLD) Working Group database between May 2009 and June 2019. Demographic characteristics such as age, sex, indications for biopsy, diagnosis of the glomerular diseases, comorbidities, laboratory and biopsy findings of all patients were recorded. The data presented is cross-sectional and includes application data for the biopsy period. According to their types, RPGN patients were classified as type 1 (anti-GBM related), type 2 (immunocomplex related) and type 3 (immune-negative; “pauci-immune”).

Results

After exclusion of 46 patients with missing data, 200 patients (mean age 47.9 ± 16.7 years, 44% female) were included in the study which constitutes 5.2% of the total glomerulonephritis database (total number of patients: 3875). Hypertension was present in 62 patients (31.0%) and diabetes was present in 18 patients (9.0%). Renal biopsy was performed in 147 (73.5%) patients due to nephritic syndrome (RPGN included). 80.2% of the patients' biopsies were performed in nephrology clinics and 19.8% of them were performed in radiology clinics. ANCA positivity was found in 121 (60.5%) patients (proteinase 3-ANCA was positive in 55 and myeloperoxidase-ANCA positive in 66 patients). Type 1 RPGN was detected in 11 (5.5%), type 2 RPGN in 42 (21%) and type 3 RPGN in 147 (73.5%) patients. In 21 patients (10.5%), biopsy revealed RPGN with advanced chronic changes (fibrous global sclerotic glomeruli, advanced interstitial fibrosis and tubular atrophy). Mean serum creatinine was 4.2 ± 3.4 mg/dl, median glomerular filtration rate was 18 (10-37) ml/min and proteinuria 2100 (1229-3526) mg/day according to CKD-EPI formula. The mean number of glomeruli in the biopsies was 18.8 ± 10.6 and the number of crescentic glomeruli was 9.9 ± 7.7 (ratio: 52.7%) (Figure). The patients were divided into 3 groups according to their crescentic glomeruli ratios. The proportion of crescentic glomeruli is 10-50% in group 1, 50-80% in group 2, and &gt;80% in group 3. The demographic, laboratory and histopathological characteristics of the groups are given in Figure. It was observed that urea and creatinine increased and calcium and hemoglobin decreased with increasing crescentic glomerular ratio.

Conclusion

Our study provides valuable demographic, clinical, laboratory and histopathological data about RPGN in our country. Our data are generally compatible with the literature. In our study, advanced chronic histopathological findings were prominent in the biopsy of 21 patients. Early biopsy should be performed to confirm the diagnosis of RPGN and to avoid unnecessary intensive immunosuppressive therapy. In addition to the treatments applied, detailed data, including patient and renal survival are needed.