4. Metabolic disorders Flashcards
What is average total protein concentration in blood?
60-80 g/l
What test is most commonly used to measure total protein blood concentration?
Biuret test
—
Best detection range for this test is 20-100 g/l
Biuret test
Used to chromatographically measure total protein concentration in blood.
—
Schematic chemical reaction: CO-NH + Cu++ + alkaline = purple colour complex
What are protein fraction of total blood protein?
- albumin
- globulin
- fibrinogen
What are the methods to measure albumin concentration?
- Spectrophotometry (bromocresol green as reagent)
- Serum electrophoresis (more expensive than spectrophotometry but is used when protein fraction analysis is the basic aim). This method provides albumin as % of the total protein so it;s necessary to know TP concentration
What is the only reason for increased blood albumin concentration?
Dehydration
What are the reasons for decreased albumin blood concentration?
- decreased intake of proteins, decreased absorption
- decreased synthesis - liver failure, acute inflammation
- increased utilisation - physiologic conditions cause mild changes: pregnancy, exercise, production (milk, eggs etc) and chronic diseases: chronic inflammation, neoplasm
- increased loss:
- via kidneys (protein losing nephropathy - PLN)
- GIT (protein losing enteropathy - PLE)
- skin (burn)
- sequestration to the body cavities
What are methods to measure globulins?
- Calculated as TP - albumin
- Serum electrophoresis
In what 5 fractions proteins are separated during electrophoresis?
- Albumin
- Alpha-1-globulins
- Alpha-2-globulins
- Beta globulins
- Gamma globulins
What are percentages of protein fractions for plasma and serum?
Plasma contains 50% albumin, 30% globulin and 20% fibrinogen
Serum contains 60% albumin, 40% globulin
Polyclonal gammopathy. Causes
Broad-based peak in the beta or gamma region
Causes: chronic inflammatory diseases, liver disease, FIP, heart worm disease, Ehrlichiosis
Beta-gamma bridging occurs in disorders with increased IgA and IgM such as lymphoma, heart worm disease and chronic active hepatitis
Monoclonal gammopathy
Seen as sharp spike in the beta or gamma region. Peak can be compared to albumin one.
Both non-neoplastic and neoplastic disorders can cause monoclonal gammopathy
What is the most common cause of monoclonal gammopathy?
Multiple myeloma (producing IgG or IgA monoclonal)
Neoplastic causes of monoclonal gammopathy
- multiple myeloma (IgG or IgA)
- lymphoma (IgM or IgG)
- chronic lymphocytic leukaemia (usually IgG)
- extramedullary plasmacytomas
- Waldenstrom’s macroglobilinemia (neoplasm of B-cells)
Non-neoplastic causes of monoclonal gammopathy
Kinda rare
- occult heart worm disease
- FIPV (rarely)
- Ehrlichia canis
- lymphoplasmacytiv enteritis, dermatitis and amyloidosis
-
What are methods to measure blood fibrinogen?
- TP plasma - TP serum
- Test used for thrombin time because clotting time directly depends on fibrinogen concentration. Reagent contains bovine thrombin and Ca++