Rituximab for the treatment of membranous nephropathy: a single-center experience.

BACKGROUND: Treatment of idiopathic membranous nephropathy with rituximab was introduced more than a decade ago following experimental data that suggested involvement of B-cell-mediated reactions in its pathogenesis. It was a logical step towards a more selective therapy with less severe side effects as compared to the recommended first-line immunosuppressive therapy with corticosteroids and different immunosuppressant drugs. METHODS: We retrospectively analyzed the anonymous data of patients who were treated with rituximab for idiopathic membranous nephropathy at our institution from January 2006 to July 2016. Daily proteinuria and serum creatinine were analyzed 3, 6, 9, and 12 months after rituximab application. The patients were divided into 4 groups according to proteinuria. We separately analyzed remission rates in the whole group and in groups with different quantity of daily proteinuria. Other history data and laboratory parameters were also compared within different groups of patients. RESULTS: The study involved 29 rituximab treatments in 26 patients: 7 (26.9%) female and 19 (73.1%) male patients. In 16 out of 29 treatment cases (55.1%), patients had been previously treated with cyclophosphamide and steroids, or cyclosporine with low dose of steroids, or both. In 72.4% of patients, antiphospholipase A2 receptor antibodies were present. In 2 cases of treatment (6.9%), patients received rituximab 375 mg/m2 of body surface area in 3 and 4 weekly doses, respectively. In all other cases, repeated rituximab applications were given as needed according to the levels of circulating CD-20 B-cells. The total remission rate in our cohort of patients was 37.9% (11 out of 29 cases). The average serum creatinine in the group of patients who achieved remission was significantly lower than in the group without remission (86.5 vs. 155.5 µmol/L, p = 0.003). There was no difference in the duration of the disease prior to treatment with rituximab between the groups (53.6 and 56.4 months, respectively). The remission rate was highest in the group with daily proteinuria less than 4 g per day (83.3%). There were no remissions in the group of patients with daily proteinuria more than 12 g per day. CONCLUSION: The remission rate after rituximab treatment in our cohort of patients with idiopathic membranous nephropathy was lower than in other studies. The reason for this is possibly the application of a single dose of rituximab in the majority of patients, which might have been insufficient in patients with higher proteinuria.
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Zika Virus-Associated Micrencephaly: A Thorough Description of Neuropathologic Findings in the Fetal Central Nervous System.

CONTEXT: -The 2015 outbreak of Zika virus in Brazil resulted in a 20-times increased prevalence of congenital microcephaly in stillborns and neonates and was instrumental in raising the suspicion of a causal association between Zika virus and microcephaly. OBJECTIVE: -To provide a comprehensive description of the neuropathologic features of congenital Zika virus infection. DESIGN: -Autopsy evaluation of the brain from a fetus of 32 weeks and 6 days of gestation, with a prenatal diagnosis of microcephaly associated with polymerase chain reaction-confirmed, fetal, Zika virus infection. RESULTS: -Multiple severe pathology findings were present. These included lissencephaly, except for the occipital lobes, where some pachygyria was observed. Also present was reduction and thinning of white matter, ventriculomegaly of the lateral ventricles, and coalescent calcifications in the cortical-subcortical white matter border associated with glioneuronal outbursting into the subarachnoid space above and heterotopias below. There were small, scattered calcifications in the basal ganglia, with fewer in the white matter and germinal matrix, and none in the cerebellum and brainstem. The cerebellum and pontine base were atrophic because of Wallerian degeneration or maldevelopment of descending tracts and pontocerebellar connections. CONCLUSION: -Our findings are in agreement with neuroimaging of Zika virus-associated fetal and infant micrencephalic brains and, to some extent, with neuroimaging of other intrauterine infections causing microcephaly.

Severe active C3 glomerulonephritis triggered by immune complexes and inactivated after eculizumab therapy.

BACKGROUND: Understanding the role of alternative complement pathway dysregulation in membranoproliferative glomerulonephritis (MPGN) has led to a dramatic shift in its classification into two subgroups: immune complex-mediated MPGN and complement-mediated MPGN, consisting of dense deposit disease and C3 glomerulonephritis (C3GN). A limited number of C3GN cases have been published to date with not yet conclusive results since the novel therapeutic approach with eculizumab was introduced. CASE PRESENTATION: We report the clinical follow-up of a 16-year-old patient in whom a diagnosis of C3GN was confirmed by immunofluorescence and electron microscopy in second and third kidney biopsies, while the first biopsy revealed idiopathic immune complex-mediated MPGN type III, Anders and Strife variant, which failed to improve after several attempts at conventional immunosuppression therapy. Although applied late in an already fairly advanced stage of the severe active form of MPGN, the efficacy of eculizumab on C3GN was evidenced clinically and pathohistologically. Its beneficial influence on pathomorphogenesis was demonstrated by a unique follow-up in the last three biopsies, despite the recent observation, confirmed in this study, of eculizumab binding within the kidney tissue. CONCLUSIONS: Clinicians and pathologists should be aware that, in some patients, an underlying genetic or acquired complement alternative pathway abnormality can be masked by an initial immune complex-mediated mechanism, which subsequently triggers an unbalanced excessive continual driving of complement terminal pathway activation and the development of C3GN. In such a patient, supplementary steroids in addition to eculizumab appear necessary to achieve an adequate response.

IgA vasculitis in adults: the performance of the EULAR/PRINTO/PRES classification criteria in adults.

BACKGROUND: In 2010, EULAR/PRINTO/PRES proposed new classification criteria for paediatric IgA vasculitis (IgAV) that have a higher diagnostic sensitivity than the 1990 ACR criteria. These criteria have so far not been evaluated in adults, in whom IgAV is considered as a rare disease. Our main objective was to compare the diagnostic performance of EULAR/PRINTO/PRES and ACR classification criteria in adult IgAV. METHODS: Adult IgAV cases fulfilling the 2012 revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides (ICHCCNV) definition of IgAV at a secondary/tertiary rheumatology referral centre were critically reviewed in a partially retrospective and partially prospective manner. First, we compared the diagnostic sensitivity of ACR and EULAR/PRINTO/PRES criteria in this group of patients. Second, the diagnostic specificity of ACR and EULAR/PRINTO/PRES was determined by applying these criteria to a control group of patients with other systemic vasculitides. RESULTS: Between 1 January 2010 and 31 December 2014 350 new cases of systemic vasculitis were identified. IgAV was diagnosed in 129, and other systemic vasculitides in 221 (123 had large, six medium and 92 small vessel vasculitis) cases according to ICHCCNV. The diagnostic sensitivity and specificity of the IgAV EULAR/PRINTO/PRES criteria were 99.2 % (95 % CI 95.4-99.9 %) and 86.0 % (95 % CI 80.7-90.3 %), and of the ACR criteria 86.8 % (95 % CI 79.7-92.1 %) and 81.0 % (95 % CI 75.2-85.9 %), respectively with an inter-criteria agreement of 77.5 % (95 % CI: 70.8-84.1 %). CONCLUSIONS: In the adult population the EULAR/PRINTO/PRES IgAV classification criteria had a higher sensitivity and specificity than the ACR criteria.

Zika Virus Associated with Microcephaly.

A widespread epidemic of Zika virus (ZIKV) infection was reported in 2015 in South and Central America and the Caribbean. A major concern associated with this infection is the apparent increased incidence of microcephaly in fetuses born to mothers infected with ZIKV. In this report, we describe the case of an expectant mother who had a febrile illness with rash at the end of the first trimester of pregnancy while she was living in Brazil. Ultrasonography performed at 29 weeks of gestation revealed microcephaly with calcifications in the fetal brain and placenta. After the mother requested termination of the pregnancy, a fetal autopsy was performed. Micrencephaly (an abnormally small brain) was observed, with almost complete agyria, hydrocephalus, and multifocal dystrophic calcifications in the cortex and subcortical white matter, with associated cortical displacement and mild focal inflammation. ZIKV was found in the fetal brain tissue on reverse-transcriptase-polymerase-chain-reaction (RT-PCR) assay, with consistent findings on electron microscopy. The complete genome of ZIKV was recovered from the fetal brain.

Fatal recurrent dermatoneuro syndrome associated with systemic AL amyloidosis.

A male patient is presented with long-lasting paraproteinemia of monoclonal IgG λ, who suffered from recurrent, and until the last one, mostly reversible episodes of dermatoneuro syndrome, described exclusively in scleromyxedema. The skin biopsy revealed λ-light chain amyloid deposition instead of changes typical for scleromyxedema. Systemic AL amyloidosis was diagnosed post mortem since the patient had no clinical signs of any other organ impairment except skin and brain. Neuropathology is described and possible etiopathogenesis of brain involvement is considered.

IgA-dominant acute poststreptococcal glomerulonephritis with concomitant rheumatic fever successfully treated with steroids: a case report.

There are only a few reports of the co-occurrence of acute poststreptococcal glomerulonephritis (APGN) and acute rheumatic fever. We report an unusual case of a 3-year-old boy with nephrotic syndrome and acute renal failure with the transitional need for peritoneal dialysis, biopsy-proven atypical IgA-dominant APGN, and concomitant acute rheumatic fever, successfully treated by steroids. Aggressive treatment with pulses of methylprednisolone proved to be successful and we recommend its use in this type of cases.

Possible role of autoimmunity in patients with premature ovarian insufficiency.

BACKGROUND: To evaluate the involvement of immune abnormality in patients with idiopathic premature ovarian insufficiency (POI). In addition to the known etiology, autoimmune disorders may be a pathologic mechanism for POI. MATERIALS AND METHODS: Our study was a prospective controlled trial. Twenty women with POI, reasons other than autoimmune excluded, were enrolled in this study. The control group consisted of 17 healthy women. In both groups, family and personal history were taken and the levels of follicle stimulating hormone, luteinizing hormone, thyroid-stimulating hormone, prolactin, anti-Müllerian hormone, inhibin B, antithyroglobulin and antithyroid peroxidase antibodies were determined. Antiovarian antibodies and subpopulations of peripheral blood T-lymhocytes were also determined. RESULTS: Participants in the study group exhibited hypergonadotropichypogonadism, while high levels of follicle stimulating hormone and low levels of inhibin B and anti-Müllerian hormone were observed. In 16 (80%) patients, POI was associated in their personal and familial history with another autoimmune disease. Fifty percent of patients presented highly elevated antithyroid antibodies. The lymphocyte subset, especially B cells, was significantly higher (p=0.014), and peripheral regulatory lymphocytes CD25+ high were significantly lower (p=0.015) in the study group than in the control group. Anti- ovarian antibodies were detected in 20% of patients with POI. CONCLUSION: We presume that the presence of anti-ovarian antibodies together with abnormalities of cellular immunity may in some cases potentially represent the involvement of an autoimmune mechanism in idiopathic POI.

Goodpasture's syndrome with concomitant immune complex mixed membranous and proliferative glomerulonephritis.

Classical Goodpasture's (GP) syndrome is a monophasic illness characterized by pulmonary hemorrhage and rapidly progressive glomerulonephritis with linear IgG deposition along the glomerular and distal tubular basement membrane and estructive necrotizing diffuse extracapillary crescentic glomerulonephritis. The majority of patients have circulating anti-glomerular basement membrane (GBM) antibodies, detectable with standard anti-GBM ELISA. Concurrence of GP syndrome with proliferative glomerulonephritis has only rarely been described. In this report, for the first time we describe in a 21-year-old woman GP syndrome with 50% crescentic sclerosing glomerulonephritis with linear immunofluorescence characteristic of anti-GBM pathogenesis, combined with mixed membranous and membranoproliferative glomerulonephritis with granular immunofluorescence and subepithelial, mesangial and subendothelial deposits characterizing immune complex pathogenesis. The clinical picture was also unusual for GP syndrome, manifesting a recurrent but non-progressive course, nephrotic syndrome, normal renal function and low values of anti-GBM antibodies, identified only by novel more sensitive techniques.

Do C1q or IgM nephropathies predict disease severity in children with minimal change nephrotic syndrome?

BACKGROUND: It has been suggested that C1q and immunoglobulin M (IgM) nephropathy are variants of minimal change nephrotic syndrome (MCNS). Many researchers believe that these two conditions signify a worse prognosis for children with MCNS in comparison with immunofluorescence (IF)-negative MCNS. The aim of our study was to determine the prognostic significance of C1q nephropathy and IgM nephropathy in children with MCNS. METHODS: Fifty-five children with MCNS who had been biopsied over the course of 24 years at our institution were retrospectively categorized into three groups on the basis of IF microscopy findings: IF-negative MCNS (29/55 patients), MCNS with IgM nephropathy (19/55 patients), and MCNS with C1q nephropathy (7/55 patients). Clinical characteristics at disease presentation, clinical course, and renal outcome were compared between groups during the median follow-up period of 16.9 years (minimum 1.0, maximum 31.1 years). RESULTS: No statistically significant differences in clinical characteristics at disease presentation, clinical course, and renal outcome were found. Children with IgM nephropathy, C1q nephropathy, and IF-negative MCNS were clinically indistinguishable. CONCLUSIONS: We concluded that C1q or IgM nephropathy variants do not seem to signify a worse prognosis in children with MCNS in comparison with IF-negative MCNS.

Urinary immunoglobulin G to albumin ratio and N-Acetyl-Beta-D-Glucosaminidase as early predictors of therapeutic response in ANCA-associated glomerulonephritis.

BACKGROUND: The aim of our study was to evaluate the prognostic value of glomerular and tubular proteinuria and tubular enzymuria as early indicators of therapeutic response to induction therapy with i.v. pulse cyclophosphamide (CyC) and methylprednisolone (MP) in patients with antineutrophil cytoplasmic antibody (ANCA) associated glomerulonephritis. METHODS AND FINDINGS: An observational single-center study was conducted in 30 patients with ANCA-associated glomerulonephritis. Patients were divided into subgroups with good or poor response to CyC therapy according to clinical and laboratory parameters. The diagnosis of ANCA-associated glomerulonephritis was based on the Chapel-Hill disease definitions. Good response to induction therapy was significantly associated with higher absolute values of urine N-acetyl-beta-D-glucosaminidase (NAG) to creatinine ratio (above 14.83 microcat/mol) and urine immunoglobulin G (IgG) to albumin ratio (above 0.09) at the time of diagnosis, while albuminuria or proteinuria did not have any early predictive value. The remission of renal disease was anticipated as early as 3 months after introduction of induction therapy in patients with reduction of urine NAG to creatinine ratio below the baseline value and in patients with at least 24% rise in eGFR. CONCLUSIONS: Urine IgG to albumin and urine NAG to creatinine ratio are better early predictors of treatment response in patients with ANCA-associated glomerulonephritis than proteinuria or albuminuria.

Figurate erythema in a patient with bullous pemphigoid and Toxocara infection.

Figurate erythema can appear in a wide spectrum of dermatological diseases. Rarely, it can present as an atypical manifestation of bullous pemphigoid. Among eosinophilic dermatoses, figurate erythema may appear in Wells syndrome, which has been occasionally reported in association with Toxocara infection. We present the case of an older female patient diagnosed with bullous pemphigoid, who presented with an unusual combination of blisters and figurate erythema outside the area of blister formation. In addition, high blood eosinophilia associated with lymph node and bone marrow eosinophilia was diagnosed and was causally related to Toxocara canis infection. The patient was treated with dapsone for bullous pemphigoid and with albendazole for toxocariosis, with complete regression of all skin lesions and blood eosinophilia. This paper discusses the possible etiopathogenesis of figurate erythema in our patient and summarizes previous clinical and histological findings in bullous pemphigoid and eosinophilic dermatoses presenting with figurate erythema lesions.

Performance evaluation of a novel chemiluminescence assay for detection of anti-GBM antibodies: an international multicenter study.

BACKGROUND: Autoantibodies to the non-collagen region (NC1) of the alpha-3 subunit of collagen IV represent a serological hallmark in the diagnosis of Goodpasture's syndrome (GPS). The objective of our study was to carefully analyze the performance characteristics of a novel anti-glomerular basement membrane (GBM) chemiluminescence immunoassay (CIA). METHODS: Sera from patients with GPS (n = 90) were collected from four clinical centers. Samples from different disease groups (n = 397) and healthy individuals (n = 400) were used as controls. All samples were tested for anti-GBM antibodies by a rapid, random access CIA (QUANTA Flash™ GBM). Most of the samples were also tested using other methods including different commercial anti-GBM IgG assays and research assays for anti-GBM IgA and IgM. RESULTS: The sensitivity and specificity of the novel CIA was 95.6% [95% confidence interval (CI) 89.0-98.8%] and 99.6% (95% CI 98.9-99.9%), respectively. Receiver operating characteristic analysis showed good discrimination between GPS patients and controls. The area under the curve was 0.98 (CI 0.96-1.0). The three anti-GBM antibody-positive samples from the control group were from two healthy individuals and one human immunodeficiency virus (HIV)-infected patient. All three individuals had low levels of anti-GBM antibodies [20, 24 and 25 chemiluminescent unit (CU), cutoff 20 CU]. When the results of the new CIA were compared to other methods, good agreement was observed: 95.8% (kappa = 0.92) versus EliA™ GBM, 97.4% (kappa = 0.95) versus both BINDAZYME™ Anti-GBM and QUANTA Lite® GBM. Anti-GBM IgA was detectable in low concentrations in patients with GPS and was associated with anti-GBM IgG but was less useful in discriminating GPS patients and controls. No discrimination was found for anti-GBM IgM. CONCLUSION: The novel QUANTA Flash™ GBM CIA demonstrated good sensitivity and specificity and had good agreement with other methods. Our data confirm that ∼5% of patients with GPS do not have detectable levels of anti-GBM antibodies.

Acute kidney injury in immunoglobulin A nephropathy: potential role of macroscopic hematuria and acute tubulointerstitial injury.

The aim of our retrospective study was to analyze the clinical course and outcome of patients with immunoglobulin A (IgA) nephropathy who presented with macroscopic hematuria and acute kidney injury (AKI). During the period from 1990 to 2005, seven out of 584 adult patients with IgA nephropathy (1.2%) fulfilled the criteria for macroscopic hematuria-induced AKI. There was an equal gender distribution among our patients, and a rather high average age at presentation (55.7 +/- 10.9 years). Four patients who were oliguric upon admission to hospital needed hemodialysis treatment. The average serum creatinine at the time of kidney biopsy was 429.8 +/- 377 micromol/L (median value 378). The percutaneous kidney needle biopsies showed focal proliferative crescentic glomerulonephritis of subclass III, according to the Haas scheme, associated with prominent red blood cell tubular casts and acute tubulointerstitial nephritis. Four patients with the most prominent crescents and tubulointerstitial involvement were treated with methylprednisolone. All patients, treated and untreated, recovered their kidney function (the serum creatinine at a median follow-up of 15 months was 111.7 +/- 38 micromol/L). In conclusion, AKI in IgA nephropathy accompanied by macroscopic hematuria appears to have been a reversible condition in our series of patients. Regarding pathogenesis, the kidney biopsy study points to the important role of glomerular bleeding with consequent, widespread obstructive red blood cell tubular casts accompanied by tubular injury and interstitial nephritis.

Clinical outcome of patients with coexistent antineutrophil cytoplasmic antibodies and antibodies against glomerular basement membrane.

Antineutrophil cytoplasmic antibodies (ANCA) and antibodies against glomerular basement membrane (anti-GBM) rarely coexist. Both antibodies may be associated with rapidly progressive glomerulonephritis and pulmonary hemorrhage. We describe the clinical, serological and histological features of our patients with dual antibodies. From 1977 to 2008, 48 patients with anti-GBM antibody-associated renal disease were observed. Eight out of the 30 tested patients (26.7%), all females, had positive myeloperoxidase (MPO)-ANCA coexistent with anti-GBM antibodies. The patients' mean age was 63.4 +/- 7.8 years. Five presented with pulmonary-renal syndrome, all but one were dialysis-dependent on admission. They had constitutional symptoms and different organ involvement. The kidney biopsies revealed intense linear staining for immunoglobulin G and C3 along the glomerular and distal tubular basement membrane associated with irregular diffuse or focal extracapillary crescentic glomerulonephritis with necrosis of varying extent. Lesions of varying ages were characteristically expressed. Seven patients were treated with methylprednisolone and plasma exchange, four with cyclophosphamide, and one with intravenous immunoglobulin. After 28-74 months, there were three dialysis-dependent survivors and one patient with stable chronic renal disease. Two clinical relapses with pulmonary involvement and MPO-ANCA positivity without anti-GBM antibodies occurred in two dialysis-dependent patients. In summary, screening for ANCA and anti-GBM antibodies should be undertaken in patients with clinical signs of systemic vasculitis. In dialysis-dependent patients, the goal of treatment is to limit the damage of other involved organs and not to preserve renal function. Careful follow-up is necessary due to the relapsing nature of the ANCA component of the disease.

Microthrombotic/microangiopathic manifestations of the antiphospholipid syndrome.

The paper presents an overview of clinical manifestations and histopathologic findings in different organs in microvascular thrombotic and microangiopathic antiphospholipid syndrome (MAPS). Subsets of antiphospholipid syndrome (APS) are presented and defined. Clinico-pathologic correlations seem insufficient so far, because of a lack of detailed systematic studies of the histopathology in different organs. Based on their own autopsy and biopsy studies, the authors propose a novel categorization of histopathologic lesions that occur in patients with classic and catastrophic APS. In addition to the already accepted category of a microvascular thrombotic type of lesions, microangiopathic lesions consistent with thrombotic microangiopathy are proposed to be included in new revised classification criteria for definite APS. Microvascular thrombotic and so far underestimated microangiopathic histopathologic lesions have been shown to appear in various combinations and of different ages in patients with both classic and catastrophic APS, which fits into the concept of MAPS. These preliminary findings of our studies are also in line with the most recent hypothesis of two main mechanisms in the pathogenesis of APS, emphasizing a key role of endothelial cell affection induced by aPL on the one hand and interference with coagulation cascade on the other side.

Hantavirus nephropathy.

Pathogenic rodent-borne hantaviruses cause in humans generalized infections that involve the peripheral vascular bed and severely affect their permeability. We describe a 30-yr-old male patient with clinical symptoms characterizing five conventional phases of hemorrhagic fever with renal syndrome after an uncommonly severe hantavirus infection with the Puumala strain. Renal biopsy in this situation typically demonstrates acute hemorrhagic interstitial nephritis, particularly pronounced in the outer medulla. Hantaviruses are not cytopathic for most cells, and their interactions with endothelial cells that activate immune mechanisms play a key role in the pathogenesis of vascular dysfunction characterizing this disease.

Pathology, clinical presentations, and outcomes of C1q nephropathy.

C1q nephropathy is an uncommon glomerular disease with characteristic features on immunofluorescence microscopy. In this report, clinicopathologic correlations and outcomes are presented for 72 patients with C1q nephropathy. The study comprised 82 kidney biopsies from 28 children and 54 adults with male preponderance (68%). Immunofluorescence microscopy showed dominant or co-dominant staining for C1q in the mesangium and occasional glomerular capillary walls. Electron-dense deposits were observed in 48 of 53 cases. Light microscopy revealed no lesions (n = 27), focal segmental glomerulosclerosis (FSGS; n = 11), proliferative glomerulonephritis (n = 20), or various other lesions (n = 14). Clinical presentations in the patients who had no lesions histology were normal urine examination (7%), asymptomatic hematuria and/or proteinuria (22%), and nephrotic syndrome (minimal change-like lesion; 63%), which frequently relapsed. All patients with FSGS presented with nephrotic syndrome. Those with proliferative glomerulonephritis usually presented with chronic kidney disease (75%) or asymptomatic urine abnormalities (20%). Of the patients with sufficient follow-up data, complete remission of the nephrotic syndrome occurred in 77% of those with a minimal change-like lesion, progression to end-stage renal disease occurred in 33% of those with FSGS, and renal disease remained stable in 57% of those with proliferative glomerulonephritis. In conclusion, this study identified two predominant clinicopathologic subsets of C1q nephropathy: (1) Podocytopathy with a minimal change-like lesion or FSGS, which typically presents with nephrotic syndrome, and (2) a typical immune complex-mediated glomerular disease that varies from no glomerular lesions to diverse forms of glomerular proliferation, which typically presents as chronic kidney disease. Clinical presentation, histology, outcomes, and presumably pathogenesis of C1q nephropathy are heterogeneous.

Spectrum of collagen type IV nephropathies: from thin basement membrane nephropathy to Alport syndrome.

Alport syndrome and thin basement membrane nephropathy are common causes of persistent familial haematuria. They are associated with various mutations in type IV collagen genes. Mutations in genes, coding for alpha5 chain of collagen IV, cause X-linked Alport syndrome, whereas mutations in genes for alpha3 and alpha4 chains can cause the autosomal recessive and autosomal dominant type of Alport syndrome or benign familial haematuria with thin basement membrane nephropathy. In view of the wide spectrum of phenotypes, an exact diagnosis is sometimes difficult to achieve. Few studies of genotype-phenotype correlations in Alport syndrome have shown that various types of mutations may be a significant predictor of the severity of disease. Histopathologic findings in Alport syndrome vary from normal kidney to nonspecific focal segmental and global glomerular sclerosis with characteristic ultrastructural finding of thickening and splitting of the glomerular basement membrane. Thin basement membrane nephropathy is characterized by diffuse thinning of the glomerular basement membrane on an ultrastructural level, while by light microscopy glomeruli are mostly unremarkable. Because of present limitations of mutation screening techniques, kidney biopsy with mandatory ultrastructural analysis and immunohistochemistry examination for type IV collagen alpha chains remains a standard approach for establishing diagnosis and determining the mode of transmission of the disease.

Light chain deposition disease restricted to the brain: The first case report.

A 35-year-old white male with symptoms of paranoid schizophrenia was treated by psychiatrists for 13 years. During the final year, he developed severe dysphagia, reduced strength of the upper extremity muscles, and cognitive dysfunction. The patient died in his sleep. The only pathology found in coronal brain sections was ill-defined periventricular foci with prominent, firm vessels. Microscopy revealed abundant, hematoxylin and eosin-eosinophilic, periodic acid-Schiff-positive, thioflavin T-positive, and Congo red-negative deposits in the vessel walls, with hypoxic encephalopathy in the affected regions. Immunohistochemistry showed lambda light chains as the main component of the deposits. Ultrastructural analysis showed amorphous electron dense material in the vessel walls. Perivascular B-cell proliferation was present in the vicinity of affected areas. Polymerase chain reaction was applied for the assessment of B-cell clonality, revealing monoclonal rearrangement of the heavy chain Ig gene. Neither in the kidney nor in any other organ were deposits detected. This is the first case report of light chain deposition disease restricted to the brain.