Investigation of APE1 and OGG1 expression in chronic hemodialysis patients.

BACKGROUND: The role of DNA repair mechanisms is of significant importance in diseases characterized by elevated oxidative DNA damage, such as chronic kidney disease. It is imperative to thoroughly understand the functions of molecules associated with DNA repair mechanisms, not only for assessing susceptibility to diseases but also for monitoring disease progression. In this research, we investigated the APE1 and OGG1 gene expression levels, both of which are involved in the base excision repair (BER) mechanism in chronic hemodialysis patients with malignancy (HPM; n = 8) and without malignancy (HP; n = 36) in pre- and post-dialysis period and 37 healty persons. We also assessed how these values correlate with the clinical profiles of the patients. METHODS AND RESULTS: We conducted gene expression analysis using real-time polymerase chain reaction (qRT-PCR). No significant differences in APE1 gene expression levels were observed in pre-dialysis when comparing the HP and HPM groups to the control group. The expression levels of the OGG1 gene were significantly lower in both the HP and HPM groups in pre- and post-dialysis periods compared to the control group. Dialysis procedures led to a reduction in APE1 and OGG1 gene expression levels in both HP and HPM groups. CONCLUSIONS: The findings of our study elucidate the impact of alterations in the base excision repair (BER) mechanism, including the hemodialysis process, in end-stage renal disease (ESRD).

Investigation of XPD, miR-145 and miR-770 expression in patients with end-stage renal disease.

BACKGROUND: The effective maintenance of genome integrity and fidelity is vital for the normal function of our tissues and organs, and the prevention of diseases. DNA repair pathways maintain genome stability, and the adequacy of genes acting in these pathways is essential for disease suppression and direct treatment responses. Chronic kidney disease is characterized by high levels of genomic damage. In this study, we examined the expression levels of the xeroderma pigmentosum group D (XPD) gene, which plays a role in the nucleotide excision repair (NER) repair mechanism, and the expression levels of miR-145 and miR-770 genes, which play a role in the regulation of the expression of the XPD gene, in hemodialysis patients with (n = 42) and without malignancy (n = 9) in pre- and post-dialysis conditions. We also evaluated these values with the clinical findings of the patients. METHODS & RESULTS: Gene expression analysis was performed by real-time polymerase chain reaction (qRT-PCR). Compared to the individuals with normal kidney function (2.06 ± 0.32), the XPD gene expression was lower in the pre-dialysis condition both in hemodialysis patients without cancer (1.24 ± 0.18; p = 0.02) and in hemodialysis patients with cancer (0.82 ± 0.114; p = 0.001). On the other hand, we found that miR-145 and miR-770 expression levels were high in both groups. We also found that expression levels were affected by dialysis processes. A statistically significant positive correlation was found between miR-145 and mir770 expression levels in the pre-dialysis group of patients with (r=-0.988. p = 0.0001) and without (r=-0.934. p = 0.0001) malignancy. CONCLUSIONS: Studies on DNA damage repair in the kidney will help develop strategies to protect kidney function against kidney diseases.

Renin-angiotensin system activation: may it increase frequency of obstructive sleep apnea in patients with autosomal dominant polycystic kidney disease?

PURPOSE: Renin-angiotensin system (RAS) hyperactivity is a common entity in both autosomal dominant polycystic kidney disease (ADPKD) and obstructive sleep apnea (OSA). We aimed to investigate the frequency of OSA in adults with ADPKD either with stages 3-4 or stages 1-2 chronic kidney disease (CKD) and evaluate the effect of RAS blockade on OSA in these patients. METHODS: This is a comparative, prospective, two-center clinical study. Eligible patients with ADPKD were enrolled in a polysomnography (PSG) study. Presence of OSA in patients with ADPKD was compared with individuals who underwent polisomnography study due to OSA symptoms. A subgroup analysis was performed in terms of the presence of OSA in ADPKD with eGFR values lower or higher than 60 ml/min/1.73 m2 (stages 3-4 and stages 1-2 CKD, respectively). RESULTS: Frequency of OSA (65%) was higher than in the general population and similar between the two groups (p = 0.367). Patients with ADPKD and eGFR ≥ 60 ml/min/1.73 m2 presented a similar frequency of OSA to the control group (p = 0.759). However, OSA was significantly more frequent in ADPKD with eGFR < 60 ml/min/1.73 m2 (p = 0.018). Subgroup analysis revealed that presence of OSA also was significantly higher in ADPKD with lower eGFR levels (eGFR < 60 ml/min/1.73 m2 and eGFR > 60 ml/min/1.73 m2) 14/17 (82%) and 12/23 (52%), respectively (p: 0.048). CONCLUSION: As kidney disease progresses, uremia and related factors of renal failure rather than RAS activation seem to play a more important role for the development of OSA in patients with ADPKD.

Renal Manifestations in Inflammatory Bowel Disease: A Cohort Study During the Biologic Era.

BACKGROUND Renal involvement can complicate the course of inflammatory bowel disease (IBD). In this study, we aimed to analyze the extent of renal manifestations in patients with IBD (Crohn disease or ulcerative colitis) during the biologic era. MATERIAL AND METHODS Patients diagnosed with and followed up for IBD for a period covering 16 years were retrospectively analyzed. Patients who received IBD diagnosis with clinical, endoscopic, and histopathological findings and were older than 18 years were enrolled in the study. Demographic, clinical, laboratory, and treatment data were retrieved from the patients' medical records. RESULTS Of the 1874 patients analyzed, the diagnosis was ulcerative colitis in 1055 patients and Crohn disease in the remaining 819. Renal manifestations were found in 105 patients (5.6%), 55 (6.7%) of whom were diagnosed with Crohn disease and 50 (4.7%) with ulcerative colitis. Renal calculi was the most common renal manifestation for both Crohn disease and ulcerative colitis. Renal manifestations were related to disease activity and surgical resection history in patients with Crohn disease, whereas no such relationship was found in patients with ulcerative colitis. CONCLUSIONS Renal manifestations may be seen in up to 6% of patients with IBD, and patients with Crohn disease seems to have more risk than do patients with ulcerative colitis. Nephrolithiasis is the most common form of renal involvement in IBD and is closely associated with disease activity. This relationship between IBD and renal manifestations should be considered, especially when there are subtle renal symptoms.

Fluctuations in Interleukin-6 Levels during Hemodialysis Sessions with Medium Cutoff Membranes: An Analysis on COVID-19 Case Series.

INTRODUCTION: Interleukin-6 (IL-6) is one of the most important mediators of inflammation. It is also the culprit for a severe disease course in COVID-19. While COVID-19 has higher mortality in hemodialysis (HD) patients, medium cutoff (MCO) membranes were previously suggested as promising tools for better patient outcomes by purging inflammatory mediators. The aim of this study was to analyze changes in IL-6 levels of HD patients who were dialyzed via MCO membranes during their COVID-19 treatments. METHODS: This is an observational study on a group of HD patients who were admitted with COVID-19 diagnosis in a university hospital and intermittently dialyzed using MCO membranes during their hospital stay. IL-6 levels of the patients were measured before and after consecutive dialysis sessions by a commercial kit. Measurements were interpreted together with the clinical data. RESULTS: Nine patients with a total of 54 measurements were evaluated. IL-6 levels were significantly higher in patients who died (median and interquartile ranges [IQRs] of IL-6 levels for patients who died and survived were 112.0 pg/mL [48.3-399.4] and 5.3 pg/mL [2.2-27.4], respectively; p < 0.001). In the comparison of changes in IL-6 levels with dialysis sessions, patients who survived had lower post-dialysis levels (median: 4.5 pg/mL; IQR: 2.2-7.6). However, IL-6 levels had a tendency to increase with dialysis sessions in patients who could not survive COVID-19 (median: 237.0 pg/mL; IQR: 53.8-418.2). CONCLUSION: This study describes over time variations in IL-6 levels of COVID-19 patients undergoing HD with MCO membranes. The trend for the changes of IL-6 levels during dialysis sessions was not uniform for all patients. Surviving patients had decreasing levels of IL-6 with consecutive dialysis sessions, while nonsurvivors had an increasing trend.

Medium Cut-Off Dialysis Membranes: Can They Have Impact on Outcome of COVID-19 Hemodialysis Patients?

INTRODUCTION: Severe acute respiratory syndrome coronavirus-2 may lead to high levels of expression of inflammatory cytokines. Medium cut-off (MCO) membranes may make greater clearances for large-middle molecules (including cytokines) than low-flux (LF) membranes. In this study, we aimed to evaluate the impact of MCO membranes on outcome of COVID-19 patients on hemodialysis (HD). METHODS: Sixty COVID-19 HD patients were included in this study. The patients were categorized into 2 groups regarding type of HD membranes. Clinical data were taken from medical records. RESULTS: Initial crp and ferritin levels, which are surragates of cytokine storm and severity of disease in COVID-19, were significantly higher in MCO membrane group compared to LF group (p = 0.037 and 0.000, respectively). Although there were more patients with severe disease in MCO group, there were no significant differences regarding need for intensive care unit and death. CONCLUSION: It may be an option to use MCO membranes in HD patients with COVID-19 in order to reduce cytokine levels and prevent cytokine storm.

Ambulatory blood pressure monitoring in living kidney donors: What changes in 10 years?

In renal transplantation, living donations have more significant benefits compared to cadaveric donations. However, a probable increase in blood pressure following donation should also be kept in mind. In this study, we investigated the long-term changes in blood pressure in living kidney donors using ambulatory blood pressure monitoring and we explored the e-GFR and albuminuria/proteinuria measurements at 3 time points. Twenty-eight living kidney donors and 39 healthy individuals were evaluated and compared at the baseline and later at the 10th year. At the 10th year, creatinine levels were higher and eGFR levels were lower in the donors, whereas the systolic and diastolic measurements of the donors and controls and the prevalence of nondipping in the donors and controls were similar. Our study may be underpowered due to its small population size. However, our results at the 10th year follow-up indicated that the risk of hypertension might not seem to have increased in the well-selected donors. In addition, the majority of our donors had preserved their GFR values. Therefore, we can suggest that living kidney donation appears to be safe in well-selected patients over a 10-year time frame.

Single-frequency and multi-frequency bioimpedance analysis: What is the difference?

AIM: Bioelectrical impedance analysis is a promising method in determining the body compartments in haemodialysis patients. In this study, we aimed to investigate the agreement between two widely used methods: the single-frequency and multi-frequency bioelectrical impedance analyses. METHODS: Maintenance haemodialysis patients were enrolled in the study. Single-frequency and multi-frequency bioelectrical impedance analyses were performed consecutively before haemodialysis. A second bioelectrical impedance analysis was performed right after the haemodialysis session. A third bioelectrical impedance analysis was performed one hour after haemodialysis. We used weight change as a measure of fluid removal during haemodialysis session. RESULTS: Bioelectrical impedance analysis estimates from both devices had significant differences. Best agreement was observed between single frequency and multifrequency devices' extracellular water estimates immediately after haemodialysis (mean difference 0.076 L). We found the best agreement between weight change and extracellular water change using single-frequency bioimpedance analysis. Moreover, one hour waiting time did not improve the agreement between weight and extracellular water changes for both devices. Different estimates seem to be caused by different raw impedance data measured by both devices and device-specific equations. CONCLUSION: There are significant differences among bioelectrical impedance measurements performed with different bioelectrical impedance analyzers. Using open source software might be an important step forward in the development of standardized measurements.

The Frequency and Associated Factors for BK Virus Infection in a Center Performing Mainly Living Kidney Transplantations.

PURPOSE: BK virus (BKV) nephropathy has increasingly become an important cause of morbidity in renal transplant recipients. We evaluated the frequency and associated factors for BKV infection in a center performing mainly living donor transplantations over a long time period. METHODS: One hundred consecutive renal transplant patients were included. Quarterly visits were planned to examine urine for decoy cells and to measure the BKV DNA in the blood and urine. Renal biopsy was performed in case of deteriorated allograft function. Serological examinations for BKV immunoglobulin G (IgG) were performed in donors. RESULTS: Throughout the entire follow-up period, the rates of viruria, viremia, and the positivity of decoy cells were 12%, 6%, and 13%, respectively. The negative and positive predictive values of decoy cells were 93.1% and 69.2%, respectively, for viruria, and 99.2% and 45.5%, respectively, for viremia. Biopsy-proven BKV nephropathy was observed in 1 patient. The BKV IgG was positive in all living donors. Viruria and viremia were associated with deceased donor transplantation, acute rejection, and pulse steroid therapy. In addition, viremia was associated with antithymocyte globulin therapy and a short duration of the posttransplant period. CONCLUSIONS: The frequency of BKV infection was lower in our transplant unit compared to previous reports. Reduced doses of immunosuppression seem to be the main factor that may explain the reduced frequency. However, an active screening strategy is still of importance for this patient group.

Cat Scratch Disease in a Renal Transplant Recipient.

Cat scratch disease (CSD) is a disorder characterized by self-limited regional lymphadenopathy and fever. We reported a case of CSD in a kidney transplant recipient who presented with fever and lymphadenopathy. Lymph node biopsy demonstrated bacterial histiocytic lymphadenitis. The patient was diagnosed with CSD. Patient had good clinical improvement after treatment. Therefore, CSD should also be borne in mind for kidney recipients though CSD had been infrequently reported in this group.

A Solid Mass in the Chest Wall.

Posttransplant lymphoproliferative disorder (PTLD) is one of the most common malignancies after kidney transplantation. Different clinical and histopathological forms of PTLD related to immunosuppression can be observed after organ transplantations. We report a 42-year-old woman who had undergone deceased donor renal transplantation with an unusual presentation of PTLD. The immunosuppressive treatment was discontinued and appropriate chemotherapy was started. However, the patient died despite this treatment. Different presentations of PTLD in transplant patients should also be kept in mind.

Urinary tuberculosis: a cohort of 79 adult cases.

We aimed to investigate the demographic, clinical, diagnostic, treatment and outcome features of patients with urinary tuberculosis (UTB). Patients with UTB admitted to seven separate centers across Turkey between 1995 and 2013 were retrospectively evaluated. The diagnosis of UTB was made by the presence of any clinical finding plus positivity of one of the following: (1) acid-fast bacilli (AFB) in urine, (2) isolation of Mycobacterium tuberculosis, (3) polymerase chain reaction (PCR) for M. tuberculosis, (4) histopathological evidence for TB. Seventy-nine patients (49.36% male, mean age 50.1 ± 17.4 years) were included. Mean time between onset of symptoms and clinical diagnosis was 9.7 ± 8.9 months. The most common signs and symptoms were hematuria (79.7%), sterile pyuria (67.1%), dysuria (51.9%), weakness (51.9%), fever (43%) and costovertebral tenderness (38%). Cystoscopy was performed in 59 (74.6%), bladder biopsy in 18 (22.8%), kidney biopsy in 1 (1.26%) and nephrectomy in 12 (15.2%) patients. Histopathological verification of UTB was achieved in 12 (63.1%) patients who undergone biopsy and in 100% of those undergone nephrectomy. Mycobacterium tuberculosis was isolated in the urine of 50 (63.3%) cases. Four-drug standard anti-TB treatment was the preferred regimen for 87.3% of the patients. Mean treatment duration was 10.5 ± 2.7 months. Deterioration of renal function occurred in 15 (18.9%) patients two of whom progressed to end-stage renal disease and received hemodialysis. Only one patient died after 74-day medical treatment period. Cases with UTB may present with non-specific clinical features. All diagnostic studies including radiology, cyctoscopy and histopathology are of great importance to exclude UTB and prevent renal failure.

Calciphylaxis: a report of six cases and review of literature.

Calciphylaxis is usually a fatal condition that develops in a few chronic renal failure patients, and it is characterized by calcifications in subcutaneous arteries, infarcts in skin, and the neighboring subcutis. Calciphylaxis, once considered as a rare condition, has been reported to have an annual incidence of 1% and a prevalence of 4% in dialysis patients. We describe our clinical experience in six end-stage renal disease patients on dialysis that presented with calciphylaxis and died due to sepsis, and review the pathogenesis, epidemiology, clinical and histopathologic features, and treatment of calciphylaxis. Physicians should initially consider the possibility of calciphylaxis in case of development of skin lesions in chronic renal failure patients with impaired calcium, phosphorus, and parathyroid hormone levels. The most important cause of mortality in this condition is infection. Therefore, differential diagnosis of these lesions from systemic vasculitis in their early stages and withdrawal of immunosuppressive therapy that increases the tendency to infections are essential.

Applicability of a different estimation equation of glomerular filtration rate in Turkey.

We aimed to investigate the performance of various creatinine based glomerular filtration rate estimation equations that were widely used in clinical practice in Turkey and calculate a correction coefficient to obtain a better estimate using the isotope dilution mass spectrometry (IDMS)-traceable Modification of the Diet in Renal Disease (MDRD) formula. This cross-sectional study included adult (>18 years) outpatients and in patients with chronic kidney disease as well as healthy volunteers. Iohexol clearance was measured and the precisions and bias of the various estimation equations were calculated. A correction coefficient for the IDMS-traceable MDRD was also calculated. A total of 229 (113 male/116 female; mean age 53.9 ± 14.4 years) subjects were examined. A median iohexol clearance of 39.21 mL/min/1.73 m(2) (range: 6.01-168.47 mL/min/1.73 m(2)) was found. Bias and random error for the IDMS-traceable MDRD equation were 11.33 ± 8.97 mL/min/1.73 m(2) and 14.21 mL/min/1.73 m(2), respectively. MDRD formula seems to provide the best estimates. To obtain the best agreement with iohexol clearance, a correction factor of 0.804 must be introduced to IDMS-traceable MDRD equation for our study population.

Arteriovenous fistula as the vascular access contributes to better survival of hemodialysis patients with COVID-19 infection.

BACKGROUND: While COVID-19 in chronic hemodialysis patients has high mortality and the pandemic will not end in the near future, effective follow up strategies should be implemented for these patients. Surgeries have been triaged according to their level of urgencies and arteriovenous fistula (AVF) operations were among elective surgeries. This study aimed to analyze the effect of vascular access on the outcomes of hemodialysis patients who had COVID-19. METHODS: One hundred four hemodialysis patients who had COVID-19 were retrospectively analyzed. Seventy-two of them had AVF as the vascular access while 32 of them had tunneled catheters. Inflammatory markers and outcomes of patients with AVFs and catheters were compared. A logistic regression analysis was performed in order to define factors that contribute to better outcomes in hemodialysis patients. RESULTS: COVID-19 had high mortality rate in hemodialysis patients (36.5%). Patients with catheters have higher peak ferritin levels (p = 0.02) and longer hospital stay (p = 0.00). Having AVF as the vascular access (OR = 3.36; 95% CI: 1.05-10.72; p = 0.041) and using medium cut-off dialyzers (OR = 7.99; 95% CI: 1.53-41.65; p = 0.014) were related to higher survival of the patients. COVID severity was inversely proportional to the survival (p = 0.000). CONCLUSIONS: AVFs contribute to higher survival of hemodialysis patients with COVID-19. Even in the pandemic era, end stage renal disease patients should be given the opportunity to have their vascular access properly created.

Renal recovery after acute kidney injury requiring urgent hemodialysis is not associated with improved survival of the patients with multiple myeloma.

BACKGROUND: Severe acute kidney injury (AKI) requiring urgent hemodialysis (uHD) is associated with considerable morbidity and mortality in patients with multiple myeloma (MM). PURPOSE: To evaluate the renal function, outcome, and survival status of patients with MM who received uHD and to compare their overall survival with MM patients who did not receive uHD. MATERIALS AND METHODS: A total of 70 eligible MM patients who received uHD were included together with 70 control patients with MM. RESULTS: In the study group, 11 patients (15.7%) were known to have pre-existing chronic kidney disease. Thirty-four percent of the study group had AKI requiring uHD at MM diagnosis. Seventy-eight percent of the study group had severe AKI due to myeloma kidney. Renal function recovered in 36 patients (51.4%). Patients with MM who became hemodialysis dependent had significantly higher serum creatinine (sCr) levels at the time of AKI compared to patients with renal recovery (p < 0.05). Logistic regression analysis showed that high sCr on admission was significantly associated with hemodialysis dependence (odds ratio 0.78; 95% CI: 0.63-0.96; p = 0.018). The median overall survival was 30 months [IQR: 26] in the study group and 84 months [IQR: 96.25] in the control group (p < 0.05). Cox regression analysis showed that the need for uHD at initial MM diagnosis was associated with reduced survival (hazard ratio (HR) 1.9; 95% CI: 1.1-3.2; p = 0.017). Renal recovery did not provide a survival benefit. CONCLUSION: The need for uHD was associated with poor survival. Recovery of renal function was not associated with improved survival.

Antibody responses to the SARS-CoV-2 vaccines in hemodialysis patients: Is inactivated vaccine effective?

INTRODUCTION: Vaccines generally have reduced effectiveness in hemodialysis patients and a similar condition may also apply for the SARS-CoV-2 vaccines. The aim of this study was to analyze humoral responses of hemodialysis patients to SARS-CoV-2 vaccines. METHODS: Eighty-five maintenance hemodialysis patients who received either inactivated or mRNA SARS-CoV-2 vaccines were investigated. Antibody levels were measured by a commercial antibody kit, which detected antibodies toward receptor binding domain of the SARS-CoV-2 spike protein. Comparative analyzes were carried between vaccine groups and with a control group of 103 healthy volunteers. RESULTS: Seropositivity rate and antibody levels were significantly lower in hemodialysis patients who received inactivated vaccine (p = 0.000). While mRNA vaccine had better immunogenicity, both vaccines protected from symptomatic infection when seropositivity was achieved. DISCUSSION/CONCLUSION: When used in the same dose with the general population, inactivated SARS-CoV-2 vaccines generate reduced humoral response in hemodialysis patients. mRNA vaccines have better immunogenicity in this group.

The Charlson Comorbidity Index: can it predict the outcome in acute kidney injury?

PURPOSE: Comorbidity has a significant impact on the health status and treatment outcome of a patient. The Charlson comorbidity index (CCI) is a frequently used scoring system, which evaluates the prognosis based on the patient's comorbid conditions. The aim of this study was to evaluate the usefulness of CCI in predicting the mortality and renal recovery in non-critically ill patients with severe AKI. METHODS: A total of 530 adult patients who were referred from the emergency department and underwent intermittent urgent hemodialysis (uHD) were enrolled in the study. Personal history for comorbidities were recorded and then assessed using the CCI. RESULTS: The mean CCI score was 3.3 ± 2.6. In our multivariate analysis, higher white blood cell count was associated with mortality (p = 0.023). The other parameters including CCI score were not found to be significantly associated with mortality excluding patients with sepsis. Moreover, the CCI was not significantly useful in the discrimination of patients with complete recovery from patients who remained dependent to dialysis. CONCLUSIONS: We could not find significant association between CCI and short-term hospital mortality and renal outcome. Whereas, malnutrition, inflammation and general aging may have impact on short-term mortality among patients.

Fabry Disease Prevalence in Renal Replacement Therapy in Turkey.

BACKGROUND: Fabry disease (FD) is an X-linked lysosomal storage disorder resulting from lack of alpha-galactosidase A (AGALA) activity in lysosomes. OBJECTIVE: In this multicenter study, we aimed to evaluate the prevalence of FD in renal transplant (Tx) recipients in Turkey. We also screened dialysis patients as a control group. METHODS: All Tx and dialysis patients were screened regardless of the presence of a primary disease. We measured the AGALA activity in all male patients as initial analysis. Mutation analysis was performed in male patients with decreased AGALA activity and in female patients as the initial diagnostic assay. RESULTS: We screened 5,657 patients. A total of 17 mutations were identified. No significant difference was observed between the groups regarding the prevalence of patients with mutation. We found FD even in patients with presumed primary kidney diseases. Seventy-one relatives were analyzed and mutation was detected in 43 of them. We detected a patient with a new, unknown mutation (p.Cys223) in the GLA gene. CONCLUSIONS: There are important implications of the screening. First, detection of the undiagnosed patients leads to starting appropriate therapies for these patients. Second, the transmission of the disease to future generations may be prevented by prenatal screening after appropriate genetic counseling. In conclusion, we suggest screening of kidney Tx candidates for FD, regardless of etiologies of chronic kidney disease.

A Rare Presentation of Immunoglobulin A Nephropathy: Acute Kidney Injury.

BACKGROUND: Acute kidney injury (AKI) is known as an uncommon presentation in immunoglobulin A nephropathy (IgAN). The aim of our study was to analyze the clinical data and biopsy findings in IgAN patients presenting with AKI. METHODS: We performed a retrospective analysis of all subjects who had biopsy-proven IgAN and presented with AKI during June 2002 September 2015. The following data were obtained from medical records. RESULTS: A total of 15 patients of 123 patients (12.2%) with primary IgAN admitted with AKI. Patients were generally male (73.3%), with a median age of 38 (interquartile range; IQR, 2,944) years. The serum creatinine at admission was above the normal range (median 2.3 [IQR, 2.14.7] mg/dL]). On histology, cellular/fibrocellular crescents were present in 6 patients. In most cases (53.3%), pathologic abnormalities associated with acute tubular injury/necrosis were defined. Red blood cell casts in tubules were present in 6 cases (40%). In all cases, interstitial mixed inflammatory cell infiltration was observed. In 4 cases, admixed eosinophils were also found. In 3 patients, biopsy specimens showed acute thrombotic microangiopathy lesions (20%). Median follow-up time was 13 (IQR, 346) months. Six patients (40%) progressed to end-stage renal disease (ESRD). Among patients diagnosed with primary IgAN and presenting without AKI, only 4 patients progressed to ESRD. The proportion of patients who progressed to ESRD presenting with AKI was significantly higher than the patients presenting without AKI (p = 0.000). CONCLUSIONS: In conclusion, AKI complicates IgAN more often.