Involvement of M1-Activated Macrophages and Perforin/Granulysin Expressing Lymphocytes in IgA Vasculitis Nephritis.

We investigated the polarisation of CD68+ macrophages and perforin and granulysin distributions in kidney lymphocyte subsets of children with IgA vasculitis nephritis (IgAVN). Pro-inflammatory macrophage (M)1 (CD68/iNOS) or regulatory M2 (CD68/arginase-1) polarisation; spatial arrangement of macrophages and lymphocytes; and perforin and granulysin distribution in CD3+ and CD56+ cells were visulaised using double-labelled immunofluorescence. In contrast to the tubules, iNOS+ cells were more abundant than the arginase-1+ cells in the glomeruli. CD68+ macrophage numbers fluctuated in the glomeruli and were mostly labelled with iNOS. CD68+/arginase-1+ cells are abundant in the tubules. CD56+ cells, enclosed by CD68+ cells, were more abundant in the glomeruli than in the tubuli, and co-expressed NKp44. The glomerular and interstitial/intratubular CD56+ cells express perforin and granulysin, respectively. The CD3+ cells did not express perforin, while a minority expressed granulysin. Innate immunity, represented by M1 macrophages and CD56+ cells rich in perforin and granulysin, plays a pivotal role in the acute phase of IgAVN.

Histopathological Features of Time-Zero Kidney Biopsy Are Predictive Factors for Posttransplant Anemia.

INTRODUCTION: Posttransplant anemia (PTA) is a common complication of kidney transplantation, associated with reduced graft survival and higher mortality. We aimed to determine the association of PTA with histopathological characteristics of time-zero allograft biopsy and donor clinical characteristics. METHODS: We conducted a retrospective, observational cohort study that included 587 patients who underwent kidney transplantation in our center. Hemoglobin levels were assessed at 6 and 12 months after transplantation, and anemia was defined according to World Health Organization criteria. The kidney allograft time-zero biopsy has been done in all investigated cases. The evaluated histopathological parameters of the kidney allografts included glomerulosclerosis, arteriolar hyalinosis (AH), vascular fibrous intimal thickening (CV), interstitial fibrosis, tubular atrophy, and interstitial fibrosis and tubular atrophy. The Banff Classification of Allograft Pathology criteria were followed to assess the allograft histopathological changes. RESULTS: The prevalence of anemia was 31.3% at 6 months after transplantation and 23.5% at 12 months. There was an association between 20-50% glomerulosclerosis and PTA in both time points, independently from estimated glomerular filtration rate. AH and interstitial fibrosis were identified as independent risk factors for anemia 6 months after transplantation. CONCLUSION: Histopathological features of time-zero kidney biopsy may be predictors of PTA. Among them, our study recognized 20-50% degree of glomerulosclerosis, AH, and CV as the most significant risk factors for PTA.

TRENDS IN PROSTATE CANCER DIAGNOSIS DURING THE COVID-19 PANDEMIC: SINGLE-INSTITUTION EXPERIENCE.

The aim of this study was to compare the number of biopsy and surgical procedures on prostate, as well as the number of newly diagnosed, histologically confirmed cases of prostate cancer during the COVID-19 pandemic at Zagreb University Hospital Center (UHC). We retrospectively collected and processed a total of 1344 histopathologic findings of the prostate at the Zagreb UHC. Our results show that during the COVID-19 pandemic, there was a statistically significant decrease in the absolute number of biopsy and surgical procedures on prostate at Zagreb UHC, and so was the number of newly diagnosed, histologically confirmed cases of prostate cancer. During the observed time of the pandemic (March 19, 2020 to December 31, 2020), there was a 37.5% decrease in the absolute number of newly diagnosed prostate cancer cases compared to the same period of the previous year (March 19, 2019 to December 31, 2019). To our knowledge, this is the first study of this kind that is based on the number of prostate cancer diagnoses in Croatia. By observing the early period of the pandemic, our results provide important guidelines for monitoring and understanding the long-term consequences of the pandemic on the prostate cancer morbidity and mortality.

UROTHELIAL CARCINOMA BEFORE AND DURING THE COVID-19 PANDEMIC IN CROATIA - A SINGLE-CENTER STUDY.

The aim of this study was to compare the number of newly diagnosed, histopathologically confirmed cases of urothelial carcinoma before and during the COVID-19 pandemic at the Zagreb University Hospital Center. We retroactively collected and analyzed 300 histopathologically confirmed urothelial carcinoma between January 1, 2019, and December 31, 2020, at the Department of Pathology and Cytology, Zagreb University Hospital Center. Our results showed that during the COVID-19 pandemic, there was a statistically significant decrease (p=0.001; χ2-test) in the number of newly diagnosed, histopathologically confirmed cases of urothelial carcinoma at the Zagreb University Hospital Center. There was a decrease in the absolute number of newly diagnosed urothelial carcinoma by 25.8% in the observed time of the pandemic (March 19, 2020 to December 31, 2020) as compared to the same period of the previous year (March 19, 2019 to December 31, 2019). Our study is the first study of this type based on the number of newly diagnosed urothelial carcinoma in Croatia. Observing the early period of the pandemic, our results provide important foundation for future monitoring and long-term consequences of the pandemic on the morbidity and mortality of urothelial carcinoma.

Histopathologic findings on indication renal allograft biopsies after recovery from acute COVID-19.

Current knowledge on histopathological changes occurring after COVID-19 in transplanted kidneys is limited. Herein, we present renal allograft pathology findings in patients recovered from COVID-19. Six patients underwent indication biopsy, and one required allograft nephrectomy after acute COVID-19. Demographic data, clinical characteristics, and laboratory findings were recorded. The histopathological analysis included light microscopy, immunostaining, and electron microscopy. Five patients were hospitalized for acute COVID-19, and all were diagnosed with imaging-confirmed pneumonia, one requiring mechanical ventilation, and two requiring dialysis. Two patients had mild form. Histopathologic examination of renal allograft specimens revealed collapsing, perihilar, tip-lesion and secondary FSGS in one patient each. One patient had borderline acute cellular rejection, and two had chronic antibody-mediated rejection. Histopathologic changes of glomerular tufts were accompanied by acute tubular injury in four patients. None of our patients had signs of viral inclusions in kidney cells. One patient died and one remained dialysis-dependent after the good initial response to treatment. Patients with collapsing and perihilar FSGS had further progression of their chronic allograft nephropathy still without need for dialysis. In conclusion, diverse kidney pathology may be found in SARS-CoV-2-infected renal transplant patients. It seems that viral infection may affect the immune system with triggering of glomerular diseases, while the acute tubular injury is of multifactorial etiology. Direct viral effect is less likely.

Open vs laparoscopic adrenalectomy for localized adrenocortical carcinoma.

OBJECTIVE: The purpose of the study was to compare the long-term outcomes of patients with localized adrenocortical carcinoma (ACC) subjected to open vs laparoscopic surgery. DESIGN: Retrospective study. PATIENTS: This retrospective study included 46 patients with the ACC ENSAT stage I-stage III of whom 23 underwent open surgery (OA group), whereas 23 were subjected to laparoscopic adrenalectomy (LA group). The main outcomes analysed in the study were differences between the OA and LA groups in recurrence-free survival (RFS) and overall survival (OS). RESULTS: Patients in OA group had larger tumours (120 [70-250] mm vs 75 [26-110] mm; P < .001), higher Ki-67 index (16 [1-65] % vs 10 [1-25] %; P = .04) and higher disease stage (P = .01) compared with the patients in the LA group. The median duration of follow-up for patients underwent OA and LA was 51 (12-174) and 53 (5-127) months, respectively. Eight patients (5 OA and 3 LA) experienced recurrent disease, whereas six patients (3 OA and 3 LA) died during follow-up. No differences in RFS and OS were found between patients who underwent open or laparoscopic surgery. CONCLUSION: The study demonstrated that in patients with localized ACC and without invasion of extra-adrenal tissues, LA is a plausible treatment option in terms of RFS and OS. However, our results are limited to referral centres with large experience in the management of patients with ACC and may not necessarily apply to nonspecialized centres.

Alternative Splicing Rescues Loss of Common Gamma Chain Function and Results in IL-21R-like Deficiency.

Inborn errors in interleukin 2 receptor, gamma (IL2RG) perturb signaling of the common gamma chain family cytokines and cause severe combined immunodeficiency (SCID). Here, we report two brothers suffering from chronic cryptosporidiosis, severe diarrhea, and cholangitis. Pan T, B, and NK cell numbers were normal, but immunophenotyping revealed defective B cell differentiation. Using whole exome sequencing, we identified a base pair deletion in the first exon of IL2RG predicted to cause a frameshift and premature stop. However, flow cytometry revealed normal surface expression of the IL-2Rγ chain. While IL-2, IL-7, and IL-15 signaling showed only mild defects of STAT5 phosphorylation in response to the respective cytokines, IL-4- and IL-21-induced phosphorylation of STAT3 and STAT6 was markedly reduced. Examination of RNA isoforms detected alternative splicing downstream of IL2RG exon 1 in both patients resulting in resolution of the predicted frameshift and 16 mutated amino acids. In silico modeling suggested that the IL-2Rγ mutation reduces the stabilization of IL-4 and IL-21 cytokine binding by affecting the N-terminal domain of the IL-2Rγ. Thus, our study shows that IL2RG deficiency can be associated with differential signaling defects. Confounding effects of alternative splicing may partially rescue genetic defects and should be considered in patients with inborn errors of immunity.

OCT4 immunohistochemistry after staging laparoscopic retroperitoneal lymphadenectomy for testicular tumor.

Twenty to thirty percent of patients with clinical stage I testicular tumor have metastases in the retroperitoneum. The aim of this study was to evaluate the role of OCT4 immunohistochemistry in histopathologic diagnosis of lymph node metastases in patients with nonseminomatous germ cell testicular tumors. All clinical stage I patients with staging laparoscopic retroperitoneal lymphadenectomy from 2001 until 2009 were included. Archived materials of dissected lymph nodes were reassessed and additional immunohistochemical staining with OCT4 antibody was performed in patients diagnosed as free from metastases. Each slide was visually estimated for the percentage of tumor cells showing nuclear immunoreactivity for OCT4. The study included 93 patients, of which 30 (32.3%) had initially positive retroperitoneal lymph nodes. Of the remaining 63 patients, materials were missing for 5 patients, so additional immunohistochemical staining was performed in 58 patients. Of these, two (3.4%) patients were OCT4 positive, suggesting a conclusion that they were initially misdiagnosed as stage I and metastasis free. OCT4 proved its value in detecting retroperitoneal metastases. Staging laparoscopic retroperitoneal lymphadenectomy for nonseminomatous germ cell testicular tumors in clinical stage I is a reasonable option for selected patients.

IgA-dominant extracapillary proliferative glomerulonephritis following Escherichia coli sepsis in a renal transplant recipient.

Postinfectious glomerulonephritis (PIGN) generally occurs in association with staphylococcal infection. We present the first reported case of IgA-dominant PIGN after Escherichia coli infection in a renal-transplant recipient. A 65-year-old patient with stable allograft function and E. coli urosepsis was treated with ciprofloxacin for 2 weeks with excellent response. One week later he developed proteinuria 16 g/day. Renal biopsy finding revealed IgA-dominant PIGN. He received steroid pulses and intravenous imunoglobulins without effect and had started with hemodialysis.

Expression of BMP-2 in Vascular Endothelial Cells of Recipient May Predict Delayed Graft Function After Renal Transplantation.

BACKGROUND/AIMS: Delayed graft function (DGF) is associated with adverse outcomes after renal transplantation. Bone morphogenetic protein-2 (BMP-2) is involved in both endothelial function and immunological events. We compared expression of BMP-2 in epigastric artery of renal transplant recipients with immediate graft function (IGF) and DGF. METHODS: 79 patients were included in this prospective study. Patients were divided in IGF group (64 patients) and DGF group (15 patients). BMP-2 expression in intima media (BMP2m) and endothelium (BMP2e) of epigastric artery was assessed by immunohistochemistry. RESULTS: Lower intensity of BMP2e staining was recorded in DGF compared to IGF. In DGF patients, 93% had no expression of BMP2e and 7% had 1st grade expression, compared to 45% and 41% in IGF group, respectively (P=0.001) (P<0.001 for no expression and P = 0.015 for 1st grade expression). Patients who had BMP2e staining positive had lower odds for DGF (OR 0.059 [0.007, 0.477]) and this remained significant even after adjustment for donor and recipient variables, cold ischemia time, and immunological matching (OR 0.038 [0.003, 0.492]). CONCLUSIONS: Our results demonstrate that BMP-2 expression in endothelial cells of epigastric arteries may predict development of DGF.

[Lysosomal acid lipase deficiency in children: our experience and a novel possibility of enzyme replacement therapy]. / Manjak lizosomske kisele lipaze u djece: vlastita iskustva i nova mogucnost enzimskoga nadomjesnog lijecenja.

Lysosomal acid lipase deficiency is an autosomal recessive disorder with two distinct clinical phenotypes. Wolman disease is rapidly progressive with onset in early infancy. Complete enzyme deficiency results in massive accumulation of cholesterol esters and triglycerides in intestines, liver, spleen and other monocyte-macrophage system cells causing malabsorption, hepatosplenomegaly, liver failure and death in early infancy. Cholesterol ester storage disease may be diagnosed in childhood or later in life. It is characterized by chronic course and variable progression. Main features are variously expressed hepatopathy, including cirrhosis and liver failure, hypercholesterolemia and premature atherosclerosis. Characteristic is pathohistological finding of microvesicular steatosis and fibrosis and patognomonic are typical cholesterol ester crystals. Diagnosis is confirmed by enzyme assay and/or gene analysis. Until recently treatment was symptomatic. Ongoing clinical trials of enzyme replacement therapy have shown very promising results. We are presenting an infant with Wolman disease and two children with cholesterol ester storage disease with the aim to raise awareness about this disease and to start optimal care early.

Liver steatosis replaced with non-invasive viral and host parametars can serve as negative predictive model in patients with chronic hepatitis-C.

Almost 70% of chronic hepatitis C (CHC) patients will have concomitant hepatic steatosis (HS) usually determined with invasive method. HS serve as negative predictive factor for lower sustained viral response (SVR) in CHC patients treated with standard of care (SOC) (PEG-IFN and Rib). Retrospective analysis of biochemical, virological and histological data in CHC patients treated with PEG-IFN and Ribavarin. Statistical analysis was carried out by Biometriha Healthcare Research. Level of significance was set to 95% (p < 0.05). 72 patients (43 M; 29 F; median age 41 y) with CHC (60 G1; 12 G3) with no concomitant metabolic syndrome were analyzed. HS ranged from 5 to 30% (median 15%). Overall accuracy of prediction of SVR based on the levels of HS was AUC=0.71 (95% CI=0.58-0.84; p=0.005). When HS was split regarding cut-off value of 5% significant difference was found between responders and non-responders to treatment (chi2 = 10.025; df = 1; p = 0.002). Overall sensitivity was 48% and specificity 91%. Conventional predictive variables (gender, age, fibrosis and genotype) where combined with HS (>5%) and all together achieved Nagelherke R squared of 34.0% in prediction of SVR, with accuracy rate of 75.0%. Further, invasive variables (fibrosis and HS) where replaced with vire mia and body mass index (BMI). All noninvasive variables together achieved Nagelkerke R squared of 26.5% in prediction of SVR with 74% accuracy rate of the logistic regression model. Very low HS (<5%) is negative predictor of SVR and can be replaced with noninvasive variables (gender, age, viremia and BMI) with same accuracy rate of the logistic regres- sion model.

[Classification of glomerulopathies]. / Klasifikacija glomerulopatija.

Glomerular diseases may be classified as acute or chronic, primary or secondary, hereditary or acquired, proliferative or non-proliferative etc. The most commonly used is the classification according to the histopathological finding. For certain types of glomerulonephritides histopathological image, as well as clinical presentation, may vary widely. A while ago there was no classification based on the pathogenesis of certain types of glomerular diseases. However, as scientists ellucidate the underlying pathogenetic mechanism, current classifications change. The latter is best shown at the example of membranoproliferative glomerulonephritis.

MAGE-A10 cancer/testis antigen is highly expressed in high-grade non-muscle-invasive bladder carcinomas.

Bladder cancer is a common urinary malignancy and a prevalent cause of cancer-related death. Current therapies of early stage non-muscle-invasive bladder cancer (NMIBC) are frequently associated with undesirable toxicities and recurrence. Active antigen-specific immunotherapy may provide a valid therapeutic option for patients with NMIBC. Cancer-testis antigens (CTA) expressed in various tumour types and in a limited range of healthy tissues may represent potential targets for specific immunotherapy. MAGE-A10 is probably the most immunogenic antigen of the MAGE-A family. We evaluated the expression of MAGE-A10 in NMIBC. Seventy-nine patients undergoing surgical treatment for NMIBC were enrolled in the study. MAGE-A10 gene expression was assessed by quantitative real-time polymerase chain reaction. Immunohistochemistry was performed on paraffin-embedded sections. MAGE-A10 gene was specifically expressed in one-third of NMIBC (n = 24: 32.43%). Gene expression was correlated with high tumour grade. MAGE-A10 protein was exclusively detectable in nuclei of tumour cells. More importantly, MAGE-A10 protein was also more frequently detectable in high-grade tumours (p = 0.0001) and in stage T1 tumours invading subepithelial tissue or lamina propria (p = 0.01). A strong correlation between MAGE-A10 staining score and tumour grade and stage could accordingly be observed. These data indicate that MAGE-A10 expression is a feature of aggressive NMIBC and might be used as a novel target for specific immunotherapy of these cancers.

Collapsing Focal Segmental Glomerulosclerosis After Kidney Transplantation: Is It a Consequence of Viral Infections?

BACKGROUND: The aim of this case study was to explore the possible link between viral infections and collapsing focal segmental glomerulosclerosis (cFSGS) in patients who underwent kidney transplantation. METHODS: This case study included 3 case reports of patients who underwent kidney transplantation. The case reports were presented clinically and pathohistologically with cFsGS as a possible consequence of viral infections. RESULTS: The first patient developed cFSGS after polymerase chain reaction for SARS-CoV2 was positive twice. He gradually developed terminal stage chronic kidney disease. The second patient developed cFSGS with high range proteinuria after cytomegalovirus infection, which has been treated with 3 lines of antiviral medicaments. The third patient developed cFSGS as a possible consequence of hepatitis B virus infection. CONCLUSIONS: This case study highlighted the importance of viral etiology in the pathway of cFSGS. Pathogenic links between viral infections and concomitant glomerulopathies are challenging, especially in immunocompromised transplanted patients.

Relationship between 4-Hydroxynonenal (4-HNE) as Systemic Biomarker of Lipid Peroxidation and Metabolomic Profiling of Patients with Prostate Cancer.

An oxidative degradation product of the polyunsaturated fatty acids, 4-hydroxynonenal (4-HNE), is of particular interest in cancer research due to its concentration-dependent pleiotropic activities affecting cellular antioxidants, metabolism, and growth control. Although an increase in oxidative stress and lipid peroxidation was already associated with prostate cancer progression a few decades ago, the knowledge of the involvement of 4-HNE in prostate cancer tumorigenesis is limited. This study investigated the appearance of 4-HNE-protein adducts in prostate cancer tissue by immunohistochemistry using a genuine 4-HNE monoclonal antibody. Plasma samples of the same patients and samples of the healthy controls were also analyzed for the presence of 4-HNE-protein adducts, followed by metabolic profiling using LC-ESI-QTOF-MS and GC-EI-Q-MS. Finally, the analysis of the metabolic pathways affected by 4-HNE was performed. The obtained results revealed the absence of 4-HNE-protein adducts in prostate carcinoma tissue but increased 4-HNE-protein levels in the plasma of these patients. Metabolomics revealed a positive association of different long-chain and medium-chain fatty acids with the presence of prostate cancer. Furthermore, while linoleic acid positively correlated with the levels of 4-HNE-protein adducts in the blood of healthy men, no correlation was obtained for cancer patients indicating altered lipid metabolism in this case. The metabolic pathway of unsaturated fatty acids biosynthesis emerged as significantly affected by 4-HNE. Overall, this is the first study linking 4-HNE adduction to plasma proteins with specific alterations in the plasma metabolome of prostate cancer patients. This study revealed that increased 4-HNE plasma protein adducts could modulate the unsaturated fatty acids biosynthesis pathway. It is yet to be determined if this is a direct result of 4-HNE or whether they are produced by the same underlying mechanisms. Further mechanistic studies are needed to grasp the biological significance of the observed changes in prostate cancer tumorigenesis.

Two sides of the same coin: a complex presentation of autosomal dominant tubulointerstitial kidney diseases: a literature review and case reports.

Introduction: Genetic kidney diseases are underdiagnosed; namely, from 7% to 40% of patients suffering from chronic kidney disease (CKD) can carry a pathogenic variant, depending on population characteristics. Hereditary tubulointerstitial kidney diseases, including autosomal dominant tubulointerstitial kidney diseases (ADTKD), are even more challenging to diagnose. ADTKD is a rare form of genetic kidney disease resulting from pathogenic variants in the MUC1, UMOD, HNF1B, REN, SEC61A1, and DNAJB11 genes. There is no typical clinical or histopathological sign of ADTKD, it is characterized by progressive CKD, an autosomal dominant inheritance pattern, and tubular atrophy with interstitial fibrosis on kidney biopsy. There is no significant proteinuria, and the urinary sediment is bland. The patients usually do not have severe arterial hypertension. There can be a history of early gout, especially when compared to the UMOD gene variants. Children can have enuresis due to a loss of renal concentration. On ultrasound, the kidneys can appear normal or small in size. Renal cysts are not pathognomonic for any of the named diseases. End-stage renal disease (ESRD) develops at the average age of 45, but this can be very variable. Family history that suggests autosomal dominant inheritance and CKD fulfilling the aforementioned characteristics of tubulointerstitial kidney disease should raise suspicion of ADTKD. In the setting of a negative family history for CKD, clinical suspicion should be raised based on clinical characteristics, including early onset of hyperuricemia or gout and compatible histology on the kidney biopsy. Contrary to the aforementioned characteristics of ADTKD, in the case of HNF1B-related disease, there is a more complex clinical presentation with extrarenal manifestations of the disease (diabetes mellitus, hypomagnesemia, neurologic and psychiatric disturbances, etc.). The diagnosis of ADTKD is based on a positive family history and a detection of the pathogenic variant in one of the genes in an affected individual. Aim: The aim of our study is to present two case reports of ADTKD with different characteristics (slowly progressive CKD vs. complex clinical presentation with an extrarenal manifestation of the disease) with a literature review. Methods: A 34-year-old patient with CKD and a positive family history of CKD in whom kidney biopsy showed nonspecific chronic changes, with only genetic analysis confirming the diagnosis of MUC1-related ADTKD. Our second case is of a 17-year-old patient with an unremarkable family history who was initially referred to genetic counseling due to cognitive and motor impairment with long-lasting epilepsy. Extensive workup revealed increased serum creatinine levels with no proteinuria and bland urinary sediment, along with hypomagnesemia. His genetic analysis revealed 17q12 deletion syndrome, causing the loss of one copy of the HNF1B gene, the AATF, and the LHX1 gene. Conclusion: Autosomal dominant tubulointerstitial kidney diseases are challenging to diagnose due to a lack of typical clinical or histopathological signs as well as an uncharacteristic and versatile clinical presentation. Increased clinical awareness is crucial for the detection of these diseases.

Testicular Germ Cell Tumor Tissue Biomarker Analysis: A Comparison of Human Protein Atlas and Individual Testicular Germ Cell Tumor Component Immunohistochemistry.

The accurate management of testicular germ cell tumors (TGCTs) depends on identifying the individual histological tumor components. Currently available data on protein expression in TGCTs are limited. The human protein atlas (HPA) is a comprehensive resource presenting the expression and localization of proteins across tissue types and diseases. In this study, we have compared the data from the HPA with our in-house immunohistochemistry on core TGCT diagnostic genes to test reliability and potential biomarker genes. We have compared the protein expression of 15 genes in TGCT patients and non-neoplastic testicles with the data from the HPA. Protein expression was converted into diagnostic positivity. Our study discovered discrepancies in three of the six core TGCT diagnostic genes, POU5F1, KIT and SOX17 in HPA. DPPA3, CALCA and TDGF1 were presented as potential novel TGCT biomarkers. MGMT was confirmed while RASSF1 and PRSS21 were identified as biomarkers of healthy testicular tissue. Finally, SALL4, SOX17, RASSF1 and PRSS21 dysregulation in the surrounding testicular tissue with complete preserved spermatogenesis of TGCT patients was detected, a potential early sign of neoplastic transformation. We highlight the importance of a multidisciplinary collaborative approach to fully understand the protein landscape of human testis and its pathologies.

Semiquantitative classification (SQC) and Oxford classifications predict poor renal outcome better than The International Study of Kidney Disease in Children (ISKDC) and Haas in patients with IgAV nephritis: a multicenter study.

INTRODUCTION: Several histologic classifications are used in the evaluation of IgA vasculitis nephritis (IgAVN), however, to date, no studies have determined which one has the strongest association with the severity of IgAVN and, as a consequence, its outcomes. MATERIALS AND METHODS: Patients included in the study were diagnosed with IgAV and IgAVN in seven tertiary university medical centers in Croatia, Italy and Israel. The International Study of Kidney Disease in Children (ISKDC), Haas, Oxford, and Semiquantitative classification (SQC) classifications were used in the analysis and description of renal biopsy. Time from biopsy to outcome evaluation was a statistically significant factor in outcome prediction that was used to define the base model, and was a covariate in all the tested models. RESULTS: Sixty-seven patients were included in this study. The SQC classification proved to be the best one in outcome prediction, followed by the Oxford classification. The ISKDC and Haas classifications could not predict renal outcome. The Oxford parameters for mesangial hypercellularity and tubular atrophy, as well as the SQC parameters for cellular crescents showed an independent statistically significant contribution to outcome prediction. High level of twenty-four hour protein excretion was associated with a higher grade in the Oxford, SQC and ISKDC classifications. Endocapillary proliferation was positively associated with the Pediatric Vasculitis Activity Score (PVAS) at diagnosis, while tubular atrophy was negatively associated. CONCLUSION: The SQC, followed by the Oxford classification were found to provide the best classifications of renal biopsy analysis in patients to predict the outcome in patients with IgAVN. Cellular crescents, mesangial hypercellularity and tubular atrophy showed significant contributions, indicating that active and chronic variables should be included in the estimation.

Clinical and histopathological characteristics of COL4A3 c.2881+1G>A variant causing Alport spectrum disorders in Croatian population.

Alport syndrome (AS) and thin basement membrane nephropathy (TBMN) are part of the spectrum of kidney disorders caused by pathogenic variants in α3, α4, or α5 chains of the collagen type IV, the major structural component of the glomerular basement membrane (GBM). Using targeted next-generation sequencing (NGS), 34 AS/TBMN patients (58.8% male) from 12 unrelated families were found positive for heterozygous c.2881+1G>A variant of the COL4A3gene, that is considered disease-causing. All patients were from the continental or island part of Croatia. Clinical, laboratory, and histopathological data collected from the medical records were analyzed and compared to understand the clinical course and prognosis of the affected patients. At the time of biopsy or first clinical evaluation, the mean age was 31 years (median: 35 years; range: 1 - 72 years). Hematuria was present in 33 patients (97.1%) and 19 (55.9%) patients had proteinuria. There were 6 (17.6%) patients with hearing loss, 4 (11.8%) with ocular lesions, and 11 (32.4%) with hypertension. Twenty-three (67.6%) patients had proteinuria at follow-up, and 5 (14.7%) patients with the median age of 48 years (range: 27-55) progressed to kidney failure, started dialysis, or underwent kidney transplantation. Of the 13 patients who underwent kidney biopsy, 4 (30.8%) developed focal segmental glomerulosclerosis (FSGS), and 8 (66.7%) showed lamellation of the GBM, including all patients with FSGS. It is essential to conduct a detailed analysis of each collagen type IV genetic variant to optimize the prognosis and therapeutic approach for affected patients.