Proteins Flashcards
Increased protein synthesis is caused by: (3)
T4, cortisol, anabolic steroids
Decreased protein synthesis
Malnutrition, malignancies, hot environments
Protein (Functions)
• Transport
• Maintain osmotic balance
• Immune defense reactions
• Coagulation
• Contribute to nitrogen needs
• Structural components
• Enzymes
• Hormones
What makes up the majority of total protein
Albumin
Albumin is synthesized in the:
Liver
-Water-Soluble
Albumin: Functions
Oncotic Pressure, Transport
Albumin: Clinical Significance
• Serum albumin depends on: synthesis, degradation, and loss of albumin, volume distribution between vascular compartments
• If synthesis and loss are not the problem, can be useful as nutritional assessment
Albumin: Increased Levels
Dehydration*
Albumin: Decreased Levels
• Chronic liver disease: Cirrhosis
• Protein-losing enteropathies (malabsorption)*
• Protein-losing nephropathies*
• Third space losses
• Malnutrition
-Tea & Toasters
Globulin: General
• Larger molecules
• Alpha, beta, gamma (antibodies)
• Synthesis: Gamma globulins-lymphoid
• Functions: Transport & Blood Clotting (Alpha + Beta), Immune functions (antibodies)
Globulin: Increased Levels
-Multiple Myeloma: B-Cells->Plasma Cells->antibodies
-Chronic inflammatory/autoimmune (RA/SLE)
-Acute/Chronic Infections
Globulin: Decreased Levels
•Genetic immune disorders
• Secondary immune disorders
Total Protein
Albumin + globulin
A:G Ratio
2:1
Reverse A:G Ratio is caused by:
Multiple Myeloma and Liver Disease
Total protein is determined by:
Nutritional state, hepatic function, renal function, hydration, various disease states
Total Protein: Increased
Dehydration, chronic infections
Total Protein: Decreased
Chronic liver, enteropathy, neuropathy, malnutrition
Chronic Liver Disease: Reversed A:G Ratio is caused by
Albumin (Low), Globulin (Normal/slight increase), Total Protein (Low)
Multiple Myeloma: Reversed A:G ratio is caused by
Albumin (Normal), Globulin (Elevated-Notable), Total Protein (Elevated or NL)
*Preferred screen after abnormalities on TP, alb, glob, A:G ratio
Protein Electrophoresis (ELP)
ELP separates protein into 5 fractions
• Albumin, Alpha 1, Alpha 2, Beta, Gamma
• Constitutes majority of circulating blood antibodies (75%)
IgG
IgG: Functions
-Material Transfer
• Responsible for major antibacterial and antiviral (forever) activity in serum
•Opsonization, agglutination
• Tumor recognition
• Neutralization of toxins, virus
• Activates complement
IgA: Functions
Mucosal immunity-Respiratory, GI, GU
IgA deficiency is associated with:
Upper respiratory and GI infections, autoimmune disease
IgM is responsible for:
• Responsible for ABO blood grouping and rheumatoid factor
-First made after antigen exposure
IgE
-Eosinophils
-Hay fever, asthma, parasitic
Smallest portion of immunoglobulins, rarely evaluated/detected
IgD
Malabsorption: Common Lab Findings
• CBC: Anemia (IDA, B12, Folate)~ACD
• Inflammatory tests: CRP/ESR
• CMP/Additional: Hypoalbumemia, Fat Soluble Vitamins (D, A, E, K), Fecal Fat Test
Gluten-Induced Enteropathy/Celiac Disease:
Immune disorder triggered by environmental agent (gliadin)
Gluten-Induced Enteropathy/Celiac Disease: Typical Presentation
• Diarrhea illness*
• Villous atrophy->malabsorption*
• Steatorrhea, weight loss, vitamin deficiencies, anemia*
• Resolution of symptoms with gluten free diet*
Celiac Disease: Digestive Signs & Symptoms
• Diarrhea, cramping, flatulence
• Steatorrhea
• Large appetite*
• Abdominal bloating, distention
• Abdominal pain, nausea
Celiac Disease: Systemic Signs & Symptoms (6)
• Weight loss
• Migraines
• Muscle cramping
• Bone/joint pain
• Edema
• Skin problems
Celiac Disease: Signs & Symptoms of Deficiency States
• Weakness
• Fatigue
• Pallor*
Celiac Disease: Special Testing
• IgA Anti-Tissue Transglutaminase Antibodies (IgA anti-tTG)*
• Total serum IgA (+): Total IgA is too low->cannot interpret*
• Anti-gliadin antibodies
• Anti-endomysial antibodies (EMA)
• Genetic testing: HLA DQ2 and DQ8*
• Zonulin: Increased intestinal permeability
• Endoscopy with biopsy*
Celiac Disease: Management
• Removal of all gluten from diets
• Watch for cross-reactive foods
• See some improvement 1-2 weeks after removal
• Most symptom resolve in 4-6 weeks
• Supplemental vitamins as needed
Lactose Intolerance
• Inability to digest lactose into glucose and galactose d/t low levels of lactase enzyme in brush border of duodenum
Lactose Intolerance: Primary
• Seen in adults with decreasing levels of lactase*
• Intolerance noted after lactose consumption*
• Intolerance level varies with amount of lactose consumed
Lactose Intolerance: Secondary
• Inability to digest lactose caused by any condition injuring intestinal mucosa (eg: diarrhea) or decreasing mucosal surface (eg: resection)
Lactose Intolerance: Signs & Symptoms
• 30 minutes to 2 hours after consumption of produces containing lactose*
• Distinguish from IBS w/ trial of lactose free diet*
• Bloating
• Rumbling
• Cramping
• Diarrhea/loose stool
• Steatorrhea
• Flatulence
Lactose Intolerance: Screening tests
Stool pH
Lactose Intolerance: Diagnostic Tests
• Lactose absorption test
• Lactose breath hydrogen test
Lactose Intolerance: Management
• Reduce or restrict dietary lactose*
• Yogurt, fermented products such as hard cheeses – better tolerated*
• May tolerate full fat milk better than skim*
• Lactase preparations: Lactic Acid
• Read labels
• Maintenance of calcium and vitamin D-Kids
• May tolerate 12-15g of lactose
• Certain probiotics can help when taken with lactose containing food
Crohn’s Disease: Digestive Signs & Symptoms
• Abdominal pain
• Diarrhea
• Bleeding
• Nausea/vomiting
• Loss of appetite
Crohn’s Disease: Systemic Signs & Symptoms (3)
• Weight loss
• Joint pain
• Skin problems
Crohn’s Disease: Tests
• CRP/ESR: Increases
• Fecal calprotectin: Intestinal Information
• Stool tests for pathogens
• Colonoscopy with biopsy
Chronic Pancreatitis: Signs & Symptoms
• Persistent/recurrent pain – LUQ*
• Pain worse after meals*
• Nausea/vomiting*
• Diarrhea/steatorrhea*
• Weight loss
• Jaundice possible: Block common bile duct
Chronic Pancreatitis: Lab Testing
• Amylase/lipase
• Abdominal ultrasound
• CT/MRI
