Flashcards in Lab Assessment Deck (67)
Changes in the CBC
What is the term for a combination of anemia, neutropenia, and thrombocytopenia?
GI Reasons for Anemia
GI blood loss
Nutritional deficiency (B12 & folate)
Alcohol as a direct toxin
What type of anemia is due to B12, folate, or myelodisplastic syndrome?
Why does GI issues cause neutropenia?
Sequestering of WBC's in the spleen because of portal hypertension
What is the etiology of portal HTN?
Cirrhosis of the liver
Why do GI issues cause thrombocytopenia?
Sequestering in the spleen secondary to portal hypertension
Applications of LFT's
Screen for the presence of liver disease
Measure efficacy of treatments for liver disease
Monitor progression of liver disease
Reflect the severity of liver disease
Cons of LFT's
Do not accurately reflect how well the liver is functioning
Abnormal values can be caused by disease unrelated to the liver
May be normal in advanced liver disease
When are enzymes released in the blood stream?
When hepatocytes are injured
What are the aminotransferases in the serum?
Alanine aminotransferase (ALT)
Aspartate aminotransferase (AST)
What is AST produced in?
Where are the highest elevations of the serum aminotransferases?
What can a rapid decline in serum aminotransferases a sign of?
Massive destruction of viable hepatocytes signaling acute liver failure
Define Alkaline Phosphatase
Group of enzymes that catalyze the hydrolysis of organic phosphate esters at an alkaline pH
Where is alkaline phosphatase produced?
Intestinal tract (sometimes)
Where else can alkaline phosphates be produced?
Placenta in the 3rd trimester
Growing children's bones
Metastatic bone CA
Where is 5'-nucleotidase found?
What is suggested when there are elevated AP & 5' nucleotidase levels?
Obstructive liver disease
What does Gamma-glutamyl transpeptidase (GGT) play a role in?
Amino acid transport
What does an elevated GGT & AP level indicate?
When can GGT be elevated?
Acute liver toxicity
What is elevated bilirubin due to?
Overproduction of bilirubin
Impaired uptake of bilirubin
Impaired conjugation or excretion of bilirubin
Backward leaking from damaged hepatocytes or bile ducts
What is bilirubin made from?
Other heme proteins
What does conjugated bilirubin relate to?
Why does unconjugated bilirubin not get filtered by the kidneys?
It adheres to the albumin
Normal urobilinogen result on a UA
What is the cycle of increased ammonia?
Catabolism of colonic bacteria in the GI tract
Enters circulation via portal vein
Intact liver clears ammonia
What can an increased ammonia concentration lead to?