Expression of the Selected Proteins of JAK/STAT Signaling Pathway in Diseases with Oral Mucosa Involvement.

The JAK/STAT signal pathway is a system of intracellular proteins used by many cytokines and growth factors to express genes responsible for the process of cell activation, proliferation and differentiation. There has been numerous inflammatory and autoimmune diseases identified where the JAK/STAT signaling is disrupted; however, there are only a few papers concerning autoimmune bullous diseases published. The aim of this study was to evaluate the expression of proteins: JAK3, STAT2, STAT4 and STAT6 in epithelium lesions in patients with pemphigus vulgaris (PV), bullous pemphigoid (BP), oral lichen planus (LP) and chronic ulcerative stomatitis (CUS), as well as in the control group. Immunohistochemistry and immunoblotting were used to evaluate expression of selected proteins. We found significantly higher expression of selected JAK/STAT proteins in oral mucosa lesions in study groups in comparison to the control group, which indicates participation of JAK/STAT pathway in pathogenesis of these diseases. In BP and PV there were no increased STAT2 expression, whereas in CUS and LP no increased STAT4 expression occurred. The differences in expression of JAK/STAT proteins in selected disorders have been observed. These results create new potential therapeutic targets for the treatment.

Close relationship between TAZhigh/SOX2high co-localization and metastasis in oral squamous cell carcinoma.

There is growing evidence which indicates that the development and the biological features of cancer such as the invasion, metastases and recurrence are related to the presence and behavior of the cancer stem cells (CSC). However, the regulatory mechanisms underlying CSCs-specific properties are poorly determined, the Hippo pathway has emerged as a fundamental regulator underlying CSCs stemness. Immunohistochemical method was used to examine the immunoexpression of SOX2, TAZ and α-SMA in oral squamous cells carcinomas: with metastases - OSCC M+ (n = 42), and without metastases - OSCC M- (n = 44), and 17 control cases. The immunoexpression of SOX2, TAZ and α-SMA was significantly increased in both group of OSCC in comparison to control groups. Moreover, significantly increased TAZ and α-SMA immunoexpression were found in OSCC M+ compared to OSCC M-. In OSCC M+ and OSCC M- groups there were statistically significant correlations between the immunoexpression of TAZ vs SOX2 (r = 0.56, p < 0.001; r = 0.33, p < 0.03 respectively), and TAZ vs α-SMA (r = 0.64, p < 0.001; r = 0.67, p < 0.001 respectively). Moreover, there was statistically significant association between TAZ high /SOX2 high coexistent immunoexpression and the presence of metastases (p < 0.007). Our results may suggest that SOX2 and TAZ could potentially cooperate and contribute to process of metastasis, especially in cases with TAZ high /SOX2 high expression.

The effect of levocetirizine and montelukast on clinical symptoms, serum level and skin expression of COX-1 and COX-2 enzymes in patients suffering from chronic autoimmune urticaria - a pilot study.

INTRODUCTION: Chronic autoimmune urticaria (CAU) lasts over 6 weeks and is characterized by circulating IgE autoantibodies or IgG against IgE or IgE receptor. AIM: To assess the clinical, laboratory and histological effects of 4-week levocetirizine and montelukast therapy in patients suffering from CAU. MATERIAL AND METHODS: Of 296 tested patients with chronic urticaria 40 had a positive ASST test. Only 17 (16 female/1 male; medium age: 44 years) fulfilled all study inclusion/exclusion criteria. The study was designed as an open, randomized trial with two arms: levocetirizine or montelukast treatment for 4 weeks following a 2-week wash-out period. All participants completed urticaria activity score (UAS) and visual analogue scale (VAS) questionnaires before and after both therapies. Blood samples and skin bioptats were obtained before and after treatment to evaluate COX-1 and COX-2 serum concentrations and skin expression. RESULTS: Clinical response to therapy measured with the UAS and VAS was better in the levocetirizine group. Both drugs caused a significant decrease in COX-1 and COX-2 serum level. COX-1 and COX-2 expression in epidermal and dermal inflammatory infiltration did not change significantly in either study group, but a significant decrease of COX-1 expression was observed when the groups were combined for analysis, and the decrease in COX-2 expression in the epidermis was of borderline significance. CONCLUSIONS: The effectiveness of levocetirizine and montelukast in treating CAU may be partly related to the reduction of COX-1 and COX-2 serum level and tissue expression, but further studies on a larger group of patients are needed to support this observation.

The number of CD163 positive macrophages is associatedwith more advanced skin melanomas, microvessels density and patient prognosis.

The study was aimed to evaluate the number of TAMs and to investigate whether they have association with microvessels density and patients' survival times. 46 cases of melanomas, divided into four groups according to the Breslow scale, were tested immunohistochemically with antibodies anti-CD68, CD163, iNOS to vizualized macrophages and anti-CD34 antibody to stain microvessels. The number of macrophages and the microvessels density were counted by hotspot analysis using an image analysis system. The study revealed increased numbers of CD68 and CD163 positive macrophages in successive stages of Breslow scale, but statistically significant differences were observed only between I and IV group for CD68 positive macrophages, and between I and III, IV group for CD163 positive macrophages. The mean number of the microvessels was significantly increased in group II, III, IV compared to group I. The correlative study showed significant positive correlations between the mean number of CD68 and CD163 positive macrophages and microvessels density. Moreover, the number of CD163 positive macrophages was associated inversely with patient's survival time. The results of our study may indicate that higher infiltration of macrophages, especially CD163 positive cells, is associated with more advanced melanomas, microvessels density and worse patient's prognosis.

T cells are involved in the induction of macrophage phenotypes in oral leukoplakia and squamous cell carcinoma-a preliminary report.

BACKGROUND: The prognosis of human malignancies has been shown to depend on immunological parameters, such as macrophage polarization (M1 and M2). In this study, we identify the phenotype of macrophages, and investigate an involvement of infiltrated T cells that participate in the polarization of macrophages, in oral leukoplakia (OLK), and oral squamous cell carcinoma (OSCC). METHODS: Immunohistochemical method was used to examine the number of CD68+ , CD163+ (M2), iNOS+ (M1) macrophages, and CD4+ , CD8+ , CCR4+ (Th2), CCR5+ (Th1) cells in 102 cases of OSCC: without metastases-OSCC M(-) (n = 54), and with metastases-OSCC M(+) (n = 48), 23 cases of OLK, and 18 control cases. RESULTS: The mean number of CD68+ , CD163+ , iNOS+ , CD4+ , CCR4+ , CCR5+ cells was significantly increased in OSCC M(+) group compared with OLK, OSCC M(-) and control group. We found positive correlations between the number of CD4+ T cells and CD163+ and iNOS+ macrophages as well as CCR4+ and CCR5+ cells in both OSCC groups. The mean number of CD8+ cells was significantly increased in OSCC M(-) and OLK compared with OSCC M(+) and control group. In OSCC M(+) and OSCC M(-) groups, a negative correlation between the number of CD8+ cells and CD163+ and iNOS+ macrophages was found. CONCLUSIONS: The number and co-localization of lymphocytes and macrophages in OLK and OSCC may indicate that infiltrating cells influence the early and subsequent stage of oral carcinogenesis.

Overexpression of ADAM10 in oral squamous cell carcinoma with metastases.

ADAMs (a disintegrin and metalloproteinase) are important mediators of cell signalling events, which play a role in the pathogenesis and progression of cancers. Immunohistochemical method was used to examine the immunoexpression of ADAM10 and microvessel density in 80 cases of oral squamous cell carcinoma (OSCC): without metastases - OSCC M(-) (n = 38), and with metastases - OSCC M(+) (n = 42), in 24 cases of oral leukoplakia (OLK), (15 cases with low-grade dysplasia - OLK-LG, and 9 cases with high-grade dysplasia - OLK-HG), and 19 controls. The immunoexpression of ADAM10 and the mean number of vessels were significantly increased in both groups of OSCC in comparison to both groups of OLK and controls. Moreover, the immunoexpression of ADAM10 and microvessel density were significantly increased in the OSCC M(+) group in comparison to the OSCC M(-) group. No statistically significant differences were found between immunoexpression of ADAM10 and microvessels density in the OLK-LG, OLK-HG, and control cases. In conclusion, the present study revealed overexpression of ADAM10 in OSCCs, especially in OSCC with metastasis. These findings suggest that ADAM10 could potentially contribute to metastases of oral cancer. Although, our findings suggest that ADAM10 may be involved in angiogenesis of OSCC, further studies are required to determine the role of ADAM10 in this process.

Clinicopathologic correlations of renal pathology in the adult population of Poland.

BACKGROUND: This is the first report on the epidemiology of biopsy-proven kidney diseases in Poland. METHODS: The Polish Registry of Renal Biopsies has collected information on all (n = 9394) native renal biopsies performed in Poland from 2009 to 2014. Patients' clinical data collected at the time of biopsy, and histopathological diagnoses were used for epidemiological and clinicopathologic analysis. RESULTS: There was a gradual increase in the number of native renal biopsies performed per million people (PMP) per year in Poland in 2009-14, starting from 36 PMP in 2009 to 44 PMP in 2014. A considerable variability between provinces in the mean number of biopsies performed in the period covered was found, ranging from 5 to 77 PMP/year. The most common renal biopsy diagnoses in adults were immunoglobulin A nephropathy (IgAN) (20%), focal segmental glomerulosclerosis (FSGS) (15%) and membranous glomerulonephritis (MGN) (11%), whereas in children, minimal change disease (22%), IgAN (20%) and FSGS (10%) were dominant. Due to insufficient data on the paediatric population, the clinicopathologic analysis was limited to patients ≥18 years of age. At the time of renal biopsy, the majority of adult patients presented nephrotic-range proteinuria (45.2%), followed by urinary abnormalities (38.3%), nephritic syndrome (13.8%) and isolated haematuria (1.7%). Among nephrotic patients, primary glomerulopathies dominated (67.6% in those 18-64 years of age and 62.4% in elderly patients) with leading diagnoses being MGN (17.1%), FSGS (16.2%) and IgAN (13.0%) in the younger cohort and MGN (23.5%), amyloidosis (18.8%) and FSGS (16.8%) in the elderly cohort. Among nephritic patients 18-64 years of age, the majority (55.9%) suffered from primary glomerulopathies, with a predominance of IgAN (31.3%), FSGS (12.7%) and crescentic GN (CGN) (11.1%). Among elderly nephritic patients, primary and secondary glomerulopathies were equally common (41.9% each) and pauci-immune GN (24.7%), CGN (20.4%) and IgAN (14.0%) were predominant. In both adult cohorts, urinary abnormalities were mostly related to primary glomerulopathies (66.8% in younger and 50% in elderly patients) and the leading diagnoses were IgAN (31.4%), FSGS (15.9%), lupus nephritis (10.7%) and FSGS (19.2%), MGN (15.1%) and pauci-immune GN (12.3%), respectively. There were significant differences in clinical characteristics and renal biopsy findings between male and female adult patients. CONCLUSIONS: The registry data focused new light on the epidemiology of kidney diseases in Poland. These data should be used in future follow-up and prospective studies.

The utility of glomerular C4d immunostaining in renal biopsies in patients with immunoglobulin A nephropathy. A clinicopathological study.

The course of IgA nephropathy (IgAN) is highly variable and ranges from a totally benign condition to end-stage renal disease in approximately one third of cases. The identification of new prognostic markers could provide insights into the pathogenesis of IgAN and unveil new therapeutic avenues. Glomerular deposition of C4d is a marker of activation of the lectin pathway of complement. It is thought that activation of the lectin pathway in IgAN is associated with more severe renal damage, and more severe histological findings. In view of the above, the aim of the present study was to compare the clinical presentation, laboratory data, and histological lesions in the renal biopsy in IgAN patients with positive and negative staining for mesangial C4d depositions. Our study revealed that hypertension, severe proteinuria, a high level of serum creatinine, low eGFR at the time of presentation, as well as tubular atrophy/interstitial fibrosis > 50%, and endocapillary proliferation were significantly more frequent in the C4d (+) group than in the C4d (-) group. Based on our research, we can assume that mesangial immunoexpression of C4d seems to be a useful prognostic factor in IgAN.

Association of infiltrating cells with microvessel density in oral squamous cell carcinoma.

Several lines of evidence indicate that immune cells in the tumor microenvironment play an important role in regulating tumor progression. An immunohistochemical method was used to examine the abundance of natural killer (NK) cells, mucosal dendritic cells (DCs), macrophages, mast cells, and microvessel density in 78 cases of oral squamous cell carcinoma (OSCC): with better prognosis - OSCCBP (n = 37), and with poorer prognosis - OSCCPP (n = 41), and 18 controls. The mean numbers of macrophages and microvessels were significantly higher in the OSCCPP group in comparison to both OSCCBP and control groups. The mean number of NK cells, mast cells and DCs was lower in the OSCCPP group in comparison to the OSCCBP group, but there were no statistically significant differences between mean numbers of NK cells in tested groups. Statistically significant correlations between the number of DCs and NK cells and mast cells, as well as between microvessel density and numbers of macrophages, DCs and mast cells were revealed in both OSCCPP and OSCCBP groups. In conclusion, our findings revealed an association between the number of infiltrating cells and oral cancer prognosis. Moreover, our results suggest that the infiltrating cells (macrophages, Langerhans and mast cells) may be involved in the process of angiogenesis.

Perirenal perivascular epithelioid cell tumor (PEComa) coexisting with other malignancies: a case report.

Perivascular epithelioid cell tumor (PEComa) is a very rare lesion and is described by the World Health Organization (WHO) as a mesenchymal tumor composed of histologically and immunohistochemically distinctive perivascular epithelioid cells. In this report we describe PEComa with perirenal manifestation, which is exceedingly rare and to our best knowledge up to now worldwide only three cases have been described. Despite the reports that most PEComas are benign, this tumor met criteria for malignancy and coexisted with mucinous gallbladder cancer and nonresectable pancreatic head tumor. We concluded that despite the rarity of perirenal PEComas, in cases with an unusual epithelioid histological pattern the diagnosis of PEComa should also be taken into consideration on the basis of the immunohistochemical study.

Tissue Factor in Dermatitis Herpetiformis and Bullous Pemphigoid: Link between Immune and Coagulation System in Subepidermal Autoimmune Bullous Diseases.

Dermatitis herpetiformis (DH) and bullous pemphigoid (BP) are skin diseases associated with eosinophilic and neutrophilic infiltrations. Although chemokines are critical for the selective accumulation and activation of various leukocyte subsets in the inflammatory process, there are few findings concerning inflammatory cells and production of coagulation factors in blistering diseases. Skin biopsies were taken from 14 patients with DH, 27 with BP, and 20 control subjects. The localization and expression of tissue factor (TF) in skin lesions and perilesional skin were studied by immunohistochemistry and confirmed by Western Blot. Moreover the plasma concentrations of TF were measured by immunoassays. D dimers, fibrinogen, and selected coagulation parameters were measured by routine methods. Expression of TF in the epidermis and in inflammatory influxed cells in dermis was detected in skin biopsies from BP patients. Examined TF expression was detected in perilesional skin of all BP patients too. The expression of TF was not observed in biopsies from healthy people and DH patients. The findings of the study show an increased expression of tissue factor in the lesional and perilesional skin of patients with bullous pemphigoid. The difference in chemokine pattern expression and variations in the cellular infiltration in BP and DH cause variable expression of TF.

Spectrum of biopsy-proven renal diseases in patients with type 2 diabetes mellitus. A single center study.

This is the first report from Poland documenting biopsy-proven renal diseases in type 2 diabetes mellitus. We analyzed the data of 76 patients with type 2 diabetes who underwent renal biopsy and were diagnosed in the Department of Nephropathology, Medical University of Lodz. The patients were divided into the following three groups according to the histological diagnosis: group I - isolated non-diabetic renal disease (NDRD); group II - NDRD superimposed on underlying diabetic nephropathy (NDRD + DN); and group III - isolated diabetic nephropathy (DN). Non-diabetic renal disease was found in 38 patients (50%), non-diabetic renal disease superimposed on underlying diabetic nephropathy was diagnosed in 11 patients (14.5%), and isolated diabetic nephropathy was seen in 27 patients (35.5%). The most common glomerular lesion found in groups I and II was focal segmental glomerulosclerosis (FSGS). On the basis of clinical and laboratory parameters, differentiating NDRD from DN in diabetic patients is not always obvious. However, our study revealed that hematuria, short duration of diabetes and the absence of diabetic retinopathy in type 2 diabetic patients manifesting renal involvement may suggest NDRD. The only way to distinguish NDRD from DN is histological evaluation of renal tissue.

Augmented immunoexpression of survivin correlates with parameters of aggressiveness in prostate cancer.

The clinical significance of the immunoexpression of survivin in prostate cancer and its correlation with the biological aggressiveness of prostate cancer remains unclear. Therefore, the present study was undertaken to compare the immunoexpression of survivin in prostate cancer (PCa) and benign prostatic hyperplasia (BPH) as well as to determine whether this immunoexpression could correlate with Gleason score, proliferation activity and prostate specific antigen (PSA) levels. The prostate needle biopsies from 28 patients with elevated serum PSA levels were studied. As a control, 12 needle biopsies of prostate diagnosed as BPH were used. The immunoexpression of survivin was evaluated semiquantitatively, whereas the Ki-67 index was assessed quantitatively. The immunoexpression of survivin and Ki-67 in epithelial cells in the prostate cancer group was significantly increased as compared to BPH cases. In the prostate cancer group there were positive significant correlations between the immunoexpression of survivin and Gleason score as well as Ki­67 antigen. The correlation between the immunoexpression of survivin and PSA levels was also positive, but it did not reach statistical significance. In conclusion, we can confirm that in prostate cancer the immunoexpression of survivin is augmented as compared to BPH and positively correlated with parameters of tumor aggressiveness.

Mediators of mast cells in bullous pemphigoid and dermatitis herpetiformis.

Bullous pemphigoid (BP) and dermatitis herpetiformis (DH) are skin diseases associated with inflammation. However, few findings exist concerning the role of mast cells in autoimmune blistering disease. Skin biopsies were taken from 27 BP and 14 DH patients, as well as 20 healthy individuals. Immunohistochemistry was used to identify the localization and mast cell expression of TNFα and MMP9 in skin lesions and perilesional skin. The serum concentrations of TNFα, MMP9, chymase, tryptase, PAF, and IL-4 were measured by immunoassay. TNFα and MMP9 expression in the epidermis and in inflammatory influxed cells in the dermis was detected in skin biopsies from patients. Although these mediators were found to be expressed in the perilesional skin of all patients, the level was much lower than that in lesional skin. Increased serum PAF levels were observed in BP patients. Mast cells may play an essential role in activating inflammation, which ultimately contributes to the tissue damage observed in BP and DH. Our findings suggest that differences in the pattern of cytokine expression directly contribute to variations in cellular infiltration in DH and BP.

Clinicopathological characteristics of segmental (IV-S) and global (IV-G) active subclasses of class IV lupus nephritis: a comparative study.

Class IV is the most common form of lupus nephritis (LN). This class is divided into diffuse segmental active subclass (IV-S/A) and diffuse global active subclass (IV-G/A). The purpose of the study was to compare the clinical data, and the incidence of glomerular active features in IV-S/A, and IV-G/A of LN. Of 34 patients with class IV LN, 25 were classified as subclass IV-G/A, and 9 patients were included in subclass IV-S/A. Nephrotic syndrome and hypertension were significantly more frequent in patients in the IV-G/A subclass, whereas hematuria and low grade proteinuria were significantly more frequent in patients in the IV-S/A subclass. Immunofluorescence findings revealed in group IV-S/A the presence of mesangial deposits and sparse deposits along the capillary wall. In contrast, an immunofluorescence study in subclass IV-G/A showed a preponderance of great subepithelial deposits. Fibrinoid necrosis of glomerular tufts was significantly more evident in subclass IV-S/A, whereas endocapillary hypercellularity, hyaline thrombi and wire loops were more frequent in subclass IV-G/A. The significant differences in clinical manifestation and in the incidence of histopathological active glomerular features between subclasses IV-S/A and IV-G/A of LN observed in our study may confirm the suggestion that these lesions have a different pathogenesis.

IL-17 expression in dermatitis herpetiformis and bullous pemphigoid.

Dermatitis herpetiformis (DH) and bullous pemphigoid (BP) are skin diseases associated with eosinophilic and neutrophilic infiltrations. Although cytokines are critical for the inflammatory process, there are single findings concerning concentration of IL-17 in bullous diseases. The goal of this study was to assess IL-17 expression in DH and BP patients. Skin biopsies were taken from 10 DH, 14 BP patients and from 10 healthy subjects. The localization and expression of IL-17 was studied by immunohistochemistry and the serum concentration was measured by immunoassays. Expression of IL-17 in the epidermis and in influxed cells in dermis was detected in skin biopsies. Expression of IL-17 was statistically higher in epidermis and infiltration cells in specimens from BP than from DH patients. Examined interleukin expression was detected in perilesional skin of all patients but it was much lower than in lesional skin. The expression of IL-17 was not observed in biopsies from healthy people. Serum level of IL-17 was statistically higher in BP and DH groups as compared to control group. Our results provide the evidence that IL-17 may play an essential role in activating and recruiting eosinophils and neutrophils, which ultimately contribute to the tissue damage in DH and BP.

Augmented mast cell infiltration and microvessel density in prostate cancer.

AIM OF THE STUDY: Recent investigations have taken into account the role of mast cells in prostate cancer formation, analyzing their dual functions (as tumour growth promoters and tumour growth inhibitors). The aim of our study was to compare mast cell infiltration and microvessel density in prostate cancer and in benign prostate hyperplasia. We also attempted to find possible relationships among mast cell infiltration and microvessel density, Gleason score, as well as serum levels of prostate-specific antigen (PSA). MATERIAL AND METHODS: The investigation was confined to evaluations of material from prostate needle biopsies, carried out in 26 patients with prostate cancer, and of 14 specimens diagnosed as benign hyperplasia. The numbers of tryptase positive mast cells and CD34 positive vessels were determined using a computer image analysis system. In the patients with prostate cancer, both mast cell infiltrates and microvessel density were significantly increased, as compared to the control patients. RESULTS: Significant positive correlations were identified between the mean numbers of mast cells and microvessel densities, both in the prostate cancer group and in the control group. Moreover, significant positive correlations were observed between Gleason score on one hand and the number of mast cells and microvessel density on the other. The correlations between PSA serum levels and both mast cell infiltration and microvessel density were positive, but not in a statistically significant way. CONCLUSIONS: The reported investigations may support the assumption of mast cell promoter function in prostate cancer development, whereas no evidence was found for their opposite.

Expression of arachidonate metabolism enzymes and receptors in nasal polyps of aspirin-hypersensitive asthmatics.

BACKGROUND: The pathogenesis of rhinosinusitis in aspirin-exacerbated airway disease is closely linked to the disequilibrium in arachidonic acid metabolism. Although considerable amounts of data concerning impaired eicosanoid production are available, the precise mechanism and pathogenesis of the disease are still unknown. The aim of the present study was to assess the expression of enzymes belonging to the arachidonic acid cascade and receptors for arachidonate derivative metabolites in nasal polyps from aspirin- hypersensitive (AH) and aspirin-tolerant (AT) patients with rhinosinusitis. METHODS: Cells expressing cysteinyl leukotriene (CysLT) receptors (CysLT(1) and CysLT(2)), arachidonate 5-lipoxygenase, leukotriene B(4) receptor type 1, E-prostanoid receptors (EP(2) and EP(4)), cyclooxygenase (COX)-1 and COX-2 were detected by immunocytochemistry in nasal polyps obtained from 10 AH patients and 18 AT patients. RESULTS: There was a significantly higher density of cells expressing CysLT(1) and CysLT(2) receptors in nasal polyps from AH patients than from AT patients (p < 0.001). In contrast, the density of cells expressing EP(2) receptor and COX-2 was significantly lower in AH patients than in AT patients (p < 0.02). The number of COX-2-positive epithelial cells was significantly reduced in AH polyps (p < 0.04). CONCLUSIONS: The elevated number of nasal polyp cells expressing CysLT receptors and lack of cells expressing EP(2) receptor and COX-2 may be related to a more severe course of hyperplastic rhinosinusitis in aspirin hypersensitivity.

Trends in the incidence of biopsy-proven glomerular diseases in the adult population in central Poland in the years 1990-2010.

BACKGROUND: There is a paucity of epidemiological data on biopsy-proven glomerulonephritis (GN) in Poland. The aim of this study was to assess the epidemiology of renal diseases based on histological diagnosis in the region of Central Poland over the last two decades. METHODS: Retrospective analysis of the results of 746 consecutive native kidney biopsies performed in the Caucasian adults from 1990 to 2010 in a single tertiary nephrology center serving an area of Central Poland. RESULTS: Primary GN was found in 81.4% of all biopsies. The mesangioproliferative GN including IgA nephropathy was the most frequent type of primary GN (51.2%). Membranoproliferative GN was diagnosed between 1990 and 2000 more frequently than in the following decade (26.7 vs. 7.3%, p < 0.001). There was a significant increase in the incidence of FSGS (4.8 vs. 17.3%, p < 0.001) and MCD (5.1 vs. 11.2%, p < 0.001) over time. Secondary GN was documented in 18.6% of biopsies and lupus nephritis was the most frequent cause (34.5%). CONCLUSION: Our analysis showed the decrease in the incidence of membranoproliferative GN with the parallel increase of FSGS and MCD over the last twenty years. Mesangioproliferative GN including IgA nephropathy remains the most frequent type of GN observed in our region.

When "diabetic nephropathy" is not always of diabetic origin: a case report.

The etiology and pathogenesis of fibrillary glomerulonephritis (FGN) remains unknown. The presented case shows an extremely rare FGN in association with commonly diagnosed diabetes. A 74-year-old, non-smoking, obese and diabetic woman was hospitalized due to a progressive and accelerated decrease in the renal function. The primary cause of chronic kidney disease was believed to be of diabetic origin. In the renal biopsy, light microscopy showed glomerular changes resembling diabetic nephropathy, however electron microscopy evaluation revealed linear, randomly arranged fibrils present in the glomerular mesangium and in peripheral capillary loops. The biopsy confirmed fibrillary glomerulopathy.