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Currently filtering by tag: Progressive renal failure

Apolipoprotein A-IV Amyloidosis

This renal biopsy from a 71-year-old female, who presented with progressively worsening renal failure, shows unremarkable glomeruli by light microscopy (Fig 1), with minimal associated tubulointerstitial chronic injury. Of note, multifocal PAS-pale, weakly argyrophilic, Congo red positive (Fig 2) deposits with apple green birefringence (Fig 3), consistent with amyloid deposits, are present exclusively within the interstitium of the renal medulla. No amyloid deposition is present within the renal cortex or involving vascular structures.  The deposits show no light chain restriction by routine or paraffin immunofluorescence (not shown), making the possibility of light chain-type amyloidosis unlikely.  Furthermore, an immunoperoxidase stain for...

Anti-Brush Border Antibody Disease IF

These photomicrographs show the classic immunofluorescence staining pattern for anti-LRP2 nephropathy, a disease that leads to severe renal tubular injury and is associated with circulating autoantibodies to the tubular brush border protein LRP2/megalin. The images show granular IgG staining along proximal tubular basement membrane, Bowman’s capsule, and segmental glomerular basement membrane staining. The presence of IgG-containing TBM immune deposits, particularly in elderly patients, should alert the clinician and pathologist to the possibility of this disorder. Similar tubular deposits can be seen in the setting of lupus nephritis and IgG4-related disease. Tubular deposits in the setting of lupus generally correlate with...

IgG4-Related Tubulointerstitial Nephritis

IgG4-related disease is a systemic inflammatory and sclerosing disorder which may affect a wide range of different organs including the pancreas, salivary glands, lacrimal glands, lungs, blood vessels, lymph nodes, thyroid and kidneys among others. Patients may have multisystemic disease at the time of presentation, or different organs may progressively become involved over time. While the renal involvement may have different histopathologic patterns of injury, by far the most common is in the form of acute or chronic tubulointerstitial nephritis (IgG4-related tubulointerstitial nephritis). The renal biopsy shown (Fig 1-4) is from a 35-year-old male with a history of lymphadenopathy and...

Calcium Phosphate Deposits

Calcium phosphate deposits within the kidney may be seen in the setting of hypercalcemia/ hypercalciuria or hyperphosphatemia/ hyperphosphaturia. Regardless of the etiology, the result is the formation of hydroxyapatite crystals within the tubular lumens (Fig 1 and 2), tubular epithelium, tubular basement membranes or within the interstitium. The term nephrocalcinosis is usually reserved to describe the presence of tubulointerstitial calcium phosphate deposits in patients with hypercalcemic disorders. These include, among others, hyperparathyroidism, sarcoidosis, underlying malignancies of various types, milk-alkali syndrome, hypervitaminosis A or D, Dent disease and other tubulopathies. On the other hand, phosphate nephropathy is predominantly seen in patients...

Diagnose This! (November 6, 2017)

What is your diagnosis?     ​   ​ ​   ​   ​ ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​ ​   ​ ​   ​ ​   ​ ​     ​   ​   ​...

Diagnose This! (October 9, 2017)

What is your diagnosis?     ​   ​ ​   ​   ​ ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​ ​   ​ ​   ​ ​   ​ ​     ​   ​   ​...

Monoclonal Gammopathy of Renal Significance

The renal biopsy shown here has an MPGN pattern of injury by light microscopy. Routine immunofluorescence on the fresh (unfixed) tissue is negative for immune reactants but repeat staining on the formalin fixed paraffin embedded tissue after protease retrieval shows positive staining for IgG and kappa. A subsequent bone marrow biopsy revealed a small clonal B-cell population. A recent case series (see reference below) detailed a cohort of patients with renal biopsy findings similar to those shown here, namely an MPGN pattern by LM and false negative staining for immunoglobulins by routine IF that are ‘unmasked monoclonal deposits’ by performing IF...

Chronic Transplant Arteriopathy

This image shows an arterial cross-section with features of chronic transplant arteriopathy (a.k.a. “sclerosing transplant vasculopathy” and “chronic allograft vasculopathy”). The lesion is characterized by fibrous intimal thickening of the arterial wall with lymphocytes (usually T-cells) and monocytes/macrophages within the thickened intima. Unlike some arteriosclerotic lesions in patients with hypertension, the arterial wall in chronic transplant arteriopathy lacks prominent accumulation of elastic fibers. Given the presence of mononuclear cells in the vessel wall, one must carefully search for endothelialitis. If found, a diagnosis of active vascular rejection, antibody-mediated rejection or acute T-cell-mediated rejection, should be considered.

Diagnose This! (September 18, 2017)

What is your diagnosis?     ​   ​ ​   ​   ​ ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​ ​   ​ ​   ​ ​   ​ ​     ​   ​   ​...

Sjogrens

Sjögren’s syndrome is an autoimmune disease involving primarily the lacrimal and salivary glands. However, up to 27% of patients will also have renal involvement. When clinical evidence of renal involvement is present, approximately 71% show evidence of interstitial nephritis on biopsy including 46% with chronic interstitial nephritis and 25% with acute interstitial nephritis. On renal biopsy, the inflammatory infiltrates in Sjögren’s-related interstitial nephritis (as shown here) is typically mononuclear and rich in plasma cells. Unlike the interstitial nephritis was seen with IgG4-related disease or lupus, there are no tubular basement membrane deposits present by immunofluorescence.