Staphylococcal Infection-Related Glomerulonephritis With Cryoglobulinemic Features.

Introduction: Staphylococcal infection-related glomerulonephritis (GN) has been shown to represent a unique form of infection-related GN that contains IgA-dominant deposits and is often seen concurrently with the bacterial infection. Biopsies commonly reveal an endocapillary proliferative and/or exudative or mesangial proliferative GN. Rare cases have been reported to show cryoglobulin-like features, including hyaline pseudothrombi and wireloop deposits; however, detailed characterization of these cases is lacking.

Collapsing Glomerulopathy in Lambda Light Chain Amyloidosis: A Report of 2 Cases.

Amyloid nephropathy is an uncommon disease that frequently presents with reduced kidney function and proteinuria and, in developed nations, is most often associated with underlying paraproteinemia. The histologic appearance of glomerular amyloid deposition includes mesangial and capillary wall infiltration by an amorphous eosinophilic material, and features of endo- or extracapillary proliferation are not typically seen. Rare cases of crescentic injury have been reported in a subset of patients with amyloid nephropathy, particularly those with amyloid derived from serum amyloid A protein.

Renal allograft granulomatous interstitial nephritis: observations of an uncommon injury pattern in 22 transplant recipients.

Granulomatous interstitial nephritis (GIN) is uncommon in native kidneys, and descriptions in allografts are few. We report clinical and pathologic findings in 22 allograft recipients with GIN identified in renal allograft biopsies and nephrectomies. Renal allografts with GIN were retrieved from the pathology files of two academic medical centers.

Variability in assessing for BK viremia: whole blood is not reliable and plasma is not above reproach - a retrospective analysis.

Polyomavirus nephropathy (PVN) is a major complication of kidney transplantation. Most reports describe polyomavirus viremia either precedes or is detectable at the time of diagnosis of PVN. This association is the basis of current screening recommendations.

Revisiting post-infectious glomerulonephritis in the emerging era of C3 glomerulopathy.

Background: Post-infectious glomerulonephritis (PIGN) is an immune complex-mediated glomerular injury that typically resolves. Dominant C3 deposition is characteristic of PIGN, but with the emergence of C3 glomerulonephritis (C3GN) as a distinct entity, it is unclear how the pathologic similarities between PIGN and C3GN should be reconciled. Therefore, nephrologists and nephropathologists need additional guidance at the time of biopsy.

Reproducibility of the NEPTUNE descriptor-based scoring system on whole-slide images and histologic and ultrastructural digital images.

The multicenter Nephrotic Syndrome Study Network (NEPTUNE) digital pathology scoring system employs a novel and comprehensive methodology to document pathologic features from whole-slide images, immunofluorescence and ultrastructural digital images. To estimate inter- and intra-reader concordance of this descriptor-based approach, data from 12 pathologists (eight NEPTUNE and four non-NEPTUNE) with experience from training to 30 years were collected. A descriptor reference manual was generated and a webinar-based protocol for consensus/cross-training implemented.

Clinical and pathological features of kidney transplant patients with concurrent polyomavirus nephropathy and rejection-associated endarteritis.

Aim: To describe the clinicopathologic features of concurrent polyomavirus nephropathy (PVN) and endarteritis due to rejection in renal allografts.

Methods: We searched our electronic records database for cases with transplant kidney biopsies demonstrating features of both PVN and acute rejection (AR). PVN was defined by the presence of typical viral cytopathic effect on routine sections and positive polyomavirus SV40 large-T antigen immunohistochemistry.

Pauci-immune glomerulonephritis in children: a clinicopathologic study of 21 patients.

Background: Pauci-immune glomerulonephritis (GN) represents a severe form of glomerular injury and is the most common cause of crescentic GN in adults. To date, the clinicopathologic features of pauci-immune GN are not well characterized in the pediatric population.

Methods: Twenty-six biopsies from 21 pediatric patients with pauci-immune GN were identified retrospectively from the pathology archives of the University of Chicago (biopsy incidence 5 % among pediatric patients).

M2 macrophage infiltrates in the early stages of ANCA-associated pauci-immune necrotizing GN.

Background And Objectives: This study examined kidney biopsies with focal segmental glomerular fibrinoid necrosis to identify early features of pauci-immune necrotizing GN and the primary effector cells mediating initial capillary injury.

Design, Setting, Participants, & Measurements: Seventeen consecutive kidney biopsies with focal pauci-immune necrotizing GN, obtained over a 6-year period (2007-2012), were studied. Neutrophils and CD68(+), CD163(+), CD3(+), CD56(+), and CD20(+) cells were scored in paraffin sections counterstained with periodic acid-Schiff.

Intratubular hemoglobin casts in hemolysis-associated acute kidney injury.

Kidney injury is a complication of intravascular hemolysis associated with many forms of hemolytic disease. Reports of kidney biopsy findings in patients with hemolysis-related kidney injury have focused primarily on the accumulation of hemosiderin pigment within proximal tubular epithelial cells (hemosiderosis), a feature of chronic hemolysis. The nephrotoxic effects of hemoglobin include direct cytotoxicity to tubular cells, but hemoglobin also can precipitate in distal nephron segments, forming obstructive casts.

Membranous nephropathy transplanted in the donor kidney: observations of resolving glomerulopathy in serial allograft biopsies.

We report a case of idiopathic, PLA2R-negative membranous nephropathy (MN) transplanted via a deceased donor kidney. Changes in glomerular immune deposits were followed in serial biopsies. The allograft recipient had end-stage disease without significant proteinuria from ischemic nephropathy due to chronic heart failure, hypertension, atherosclerosis and presumed diabetic nephropathy.

Reuse of a previously transplanted kidney: does success come with a price?

Longer wait times for deceased donor kidney transplant have prompted newer initiatives to expedite the process. Reuse of a previously transplanted kidney might be appropriate in certain circumstances. However, one must also consider the unique issues that may arise after such transplants.

Bile cast nephropathy is a common pathologic finding for kidney injury associated with severe liver dysfunction.

Cholemic nephrosis represents a spectrum of renal injury from proximal tubulopathy to intrarenal bile cast formation found in patients with severe liver dysfunction. However, the contribution of this diagnosis has been largely forgotten in the modern literature. To more precisely define this, we conducted a clinicopathologic study of 44 subjects (41 autopsies and 3 renal biopsies) from jaundiced patients at the University of Chicago.

A study of interobserver reproducibility of morphologic lesions of focal segmental glomerulosclerosis.

The morphology of focal segmental glomerulosclerosis (FSGS) includes collapsing, cellular, and sclerosing forms. The Columbia Working Classification of FSGS divides these into collapsing (COLL), cellular (CELL), tip lesion (TIP), perihilar (PH), and not otherwise specified (NOS) morphologic forms. This study examined the ability of renal pathologists to classify FSGS using single light microscopic images of glomeruli as a uniform data set.

Trisomy 8 in myeloid leukemia cutis confirmed by fluorescence in situ hybridization analysis.

We present a case of a 64-year-old man with refractory acute myeloid leukemia and trisomy 8 who developed leukemia cutis. Interphase fluorescence in situ hybridization (FISH) was performed on a paraffin-embedded skin section. FISH confirmed a population of cells with trisomy 8 in the blastic infiltrates involving the skin.

AA amyloidosis in the renal allograft: a report of two cases and review of the literature.

AA amyloidosis is a disorder characterized by the abnormal formation, accumulation and systemic deposition of fibrillary material that frequently involves the kidney. Recurrent AA amyloidosis in the renal allograft has been documented in patients with tuberculosis, familial Mediterranean fever, ankylosing spondylitis, chronic pyelonephritis and rheumatoid arthritis. De novo AA amyloidosis is rarely described.

Plasma cell densities and glomerular filtration rates predict renal allograft outcomes following acute rejection.

The contribution of T cells and graft-reactive antibodies to acute allograft rejection is widely accepted, but the role of graft-infiltrating B and plasma cells is controversial. We examined 56 consecutive human renal transplant biopsies classified by Banff schema into T-cell-mediated (N = 21), antibody-mediated (N = 18), and mixed (N = 17) acute rejection, using standard immunohistochemistry for CD3, CD20, CD138, and CD45. In a predominantly African-American population (75%), neither Banff classification nor C4d deposition predicted the return to dialysis.

A spectrum of morphologic lesions of focal segmental glomerulosclerosis by Columbia criteria in human immunodeficiency virus infection.

The Columbia working classification of focal segmental glomerulosclerosis (FSGS) identifies five types of glomerular lesions, designated collapsing (COLL), cellular (CELL), glomerular tip lesion (GTL), perihilar (PH), and not otherwise specified (NOS) variant lesions. FSGS COLL and non-collapsing variants of FSGS are described in human immunodeficiency virus (HIV)-associated kidney disease. This study examined the range and relationships of Columbia-type segmental sclerosing lesions in biopsies from patients with HIV infection.

Intragraft vascular occlusive sickle crisis with early renal allograft loss in occult sickle cell trait.

Early renal allograft failure due to sickle cell trait is rare. We present clinical and pathologic findings in 2 cases of early renal allograft failure associated with renal vein thrombosis and extensive erythrocyte sickling. Hemoglobin AS was identified in retrospect.

In situ B cell-mediated immune responses and tubulointerstitial inflammation in human lupus nephritis.

The most prevalent severe manifestation of systemic lupus erythematosus is nephritis, which is characterized by immune complex deposition, inflammation, and scarring in glomeruli and the tubulointerstitium. Numerous studies indicated that glomerulonephritis results from a systemic break in B cell tolerance, resulting in the local deposition of immune complexes containing Abs reactive with ubiquitous self-Ags. However, the pathogenesis of systemic lupus erythematosus tubulointerstitial disease is not known.

Thrombotic microangiopathy and peritubular capillary C4d expression in renal allograft biopsies.

Background And Objectives: This study characterizes the pathologic and clinical relationships of thrombotic microangiopathy (TMA) to antibody-mediated rejection (AMR) in renal allograft biopsies.

Design, Setting, Participants, & Measurements: Consecutive renal allograft biopsies, routinely stained for C4d over a period of 51 months (n=1101), were reviewed. For comparative analysis of histology and clinical features, additional patients with TMA and peritubular capillary (PTC) C4d (n=5) were combined with those identified in the 51-month period of review (n=6).