USMLE Forum Archives - USMLE Step 1 - Pathology 54
Pathology 54
TheOne - 04-27-07 10:09
A 46-year-old female with rheumatoid arthritis develops progressively worsening renal failure. She undergoes diagnostic renal biopsy, revealing thickening of the mesangial matrix and widened capillary basement membranes due to deposition of an amorphous, eosinophilic material that stains with Congo red. The material is shown to be composed of AA (amyloid-associated) protein fibrils. In which of the following locations is this protein synthesized?
A. Bone marrow
B. Brain
C. Liver
D. Synovium
E. Thyroid
TheOne - 04-27-07 10:09
A 46-year-old female with rheumatoid arthritis develops progressively worsening renal failure. She undergoes diagnostic renal biopsy, revealing thickening of the mesangial matrix and widened capillary basement membranes due to deposition of an amorphous, eosinophilic material that stains with Congo red. The material is shown to be composed of AA (amyloid-associated) protein fibrils. In which of the following locations is this protein synthesized?
A. Bone marrow
B. Brain
C. Liver
D. Synovium
E. Thyroid
Page 1
#2
Re: Pathology 54
TheOne - 05-03-07 13:33 The correct answer is C. AA protein represents an enzymatically degraded form of SAA (serum amyloid-associated) protein, which is synthesized in the liver. SAA is produced in response to cytokines that are released in a number of inflammatory conditions, including chronic infections, connective tissue disorders, and inflammatory bowel disease. It is not known why only a minority of people with these conditions develop amyloidosis. Bone marrow (choice A) and lymph nodes are the source of the AL (amyloid light chain) proteins, which cause amyloidosis in plasma cell and B-cell proliferations (e.g., multiple myeloma). This is the most common form of amyloidosis in the U.S. today. Beta 2-amyloid protein (A Beta 2) is found in the brain (choice B) and forms the core of the plaques in Alzheimer's disease. The synovium (choice D) may be the site of chronic inflammation and pannus formation in rheumatoid arthritis, but amyloid is not synthesized here. In medullary carcinoma, excess calcitonin production leads to heavy amyloid deposition within the thyroid gland (choice E), but this amyloid is not derived from AA protein.
#5
Re: Pathology 54 galaxy - 05-29-10 03:11 A 46-year-old female with rheumatoid arthritis develops progressively worsening renal failure. She undergoes diagnostic renal biopsy, revealing thickening of the mesangial matrix and widened capillary basement membranes due to deposition of an amorphous, eosinophilic material that stains with Congo red. The material is shown to be composed of AA (amyloid-associated) protein fibrils. In which of the following locations is this protein synthesized?
C. Liver
#6
Re: Pathology 54 babbu5508 - 06-21-10 02:33 amyloid is synthesized in liver and its abnormal accumulation in organs may lead to amyloidosis, and may play a role in various other neurodegenerative diseases.
#7
Re: Pathology 54 bingousmle - 06-30-10 22:55 in the liver AA is produced in response to cytokines that are released in a number of inflammatory conditions like RA and others
#10
Re: Pathology 54 babbu5508 - 09-24-10 06:57 Amyloids are insoluble fibrous protein aggregates sharing specific structural traits. Abnormal accumulation of amyloid synthesised by liver in organs may lead to amyloidosis, and may play a role in various other neurodegenerative diseases.
#13
Re: Pathology 54 babbu5508 - 09-28-10 04:52 Primary amyloidoses arise from a disease with disordered immune cell function such as multiple myeloma and other immunocyte dyscrasias.
Secondary (reactive) amyloidoses are those occurring as a complication of some other chronic inflammatory or tissue destructive disease. Examples are reactive systemic amyloidosis
Page 1