arrow-right-realarrow-rightarrow-rightback-to-topdoctordownloadfacebookinstagramlogologo-wordmarkcasttwitter
Close Modal

Blog


Currently filtering by tag: Monoclonal gammopathy of renal significance

Art of Medicine: Fanconi Syndrome

This painting shows the transition between a proximal tubule and the thick descending limb of the loop of Henle.  The proximal tubule has numerous functions, including transport of sodium chloride, bicarbonate, glucose, amino acids, organic cations, organic anions, and phosphate.  Disruption of proximal tubule function manifests clinically as Fanconi syndrome.   Development of polyuria, osteomalacia, muscle weakness, and growth failure can result if it is unrecognized and untreated. Fanconi syndrome can be diagnosed by clinical chemistry tests, including urine sodium, potassium, calcium, phosphate, glucose, amino acids, and uric acid levels, as well as urine pH.   In Fanconi syndrome, there is glycosuria...

Diagnose This (April 1, 2019)

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

Diagnose This (February 25, 2019)

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

AL Amyloidosis

A 70 year-old female presents with nephrotic range proteinuria and a creatinine of 1.2. She was in her normal level of health until about 6 months ago when she noticed foamy urine and swelling in her ankles. She has lost 30 lbs unintentionally during the last few months. Her cardiologist said that her proteinuria does not appear to be related to the heart. A kidney biopsy is performed. The glomerulus in figure 1 is distorted and has a “washed-out” or pale appearance on PAS stain. A silver stain shows material which is non-argyrophilic (figure 2). A Congo red stain shows...

Art of Medicine: Light Chain Proximal Tubulopathy

The painting above shows light chain proximal tubulopathy with crystals, which is one type of a monoclonal gammopathy of renal significance (MGRS).  MGRS, as defined by the International Kidney and Monoclonal Gammopathy Research Group, is a “clonal proliferative disorder that produces a nephrotoxic monoclonal immunoglobulin” (Leung N et al, 2019), and indicates end-organ damage resulting from a monoclonal gammopathy.   The most common MGRS manifestations include AL amyloidosis, monoclonal immunoglobulin deposition disease, light chain cast nephropathy, and light chain proximal tubulopathy.   In light chain proximal tubulopathy, a nephrotoxic monoclonal light chain induces acute tubular injury or proximal tubular dysfunction.  Proximal tubular...

Twitter Poll (December 7, 2018)

ANSWER: D MGRS was introduced to acknowledge a clonal plasma cell or B lymphocyte proliferation causing a renal lesion in the absence of hematologic malignancy or other myeloma-defining events; the renal lesion is a consequence of the MIg, which carries major implications for management and prognosis, including the potential for progressive renal injury and ESRD. MGRS caused by PC is defined as <10% bone marrow plasma cells (BMPCs), <3 g/dl of M protein, and the presence of renal lesions without any other myeloma-defining events (CRAB features; clonal PC ≥60%; serum FLC ratio of ≥100; or >1 focal lesion on magnetic...

Diagnose This (November 12, 2018)

What is your diagnosis and what do you need to prove it?           ​ ​   ​   ​ ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​   ​ ​   ​ ​   ​ ​  ...

Diagnose This! (August 6, 2018)

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

Diagnose This (July 23, 2018)

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

Peritubular Giant Cells

When giant cells surround tubules… This renal biopsy was taken from a young woman with an elevated serum creatinine (4.3 mg/dL), hematuria, and proteinuria. By light microscopy, there is a prominent giant cell reaction surrounding many of the tubules (Fig 1), the differential diagnosis of which includes so-called giant cell tubulitis (a form of tubulointerstitial nephritis associated with tubular basement membrane immune complex deposits), lupus tubulointerstitial nephritis, and monoclonal immunoglobulin deposition disease. By immunofluorescence, there is intense positivity of the tubular and glomerular basement membranes for kappa light chain (3+) with no corresponding staining for lambda light chain (Fig 2-3)....