Serum Albumin Level Test
Serum Albumin: An Overview
Serum albumin is the most abundant protein in human plasma, playing a critical role in maintaining physiological balance. Synthesized exclusively in the liver, this versatile protein serves multiple essential functions in the human body. Its significance extends from maintaining oncotic pressure to acting as a crucial transport mechanism for various substances.
Key characteristics of serum albumin include:
- Comprises 50-60% of total plasma protein
- Has a half-life of approximately 20 days
- Functions as a negative acute phase reactant
- Serves as a vital marker for nutritional status and liver function
Molecular Structure and Physiological Functions
Albumin is a complex protein with a sophisticated molecular architecture. Consisting of a single polypeptide chain of 585 amino acids, it has a molecular weight of 66.5 kDa and contains 17 critical disulfide bonds. This intricate structure enables its multifaceted biological roles.
Primary physiological functions include:
- Transport of fatty acids, hormones, vitamins, and medications
- Regulation of pH and vascular permeability
- Providing antioxidant and anticoagulant effects
- Modulating immune system responses
Diagnostic and Prognostic Applications
Serum albumin levels offer invaluable insights into a patient's overall health status. Medical professionals use albumin measurements to assess nutritional condition, detect underlying diseases, and predict potential health outcomes.
Key diagnostic applications include:
- Evaluating nutritional status and protein-energy malnutrition
- Monitoring liver and kidney function
- Assessing inflammatory conditions
- Predicting mortality risk in critical illness
Sample Collection and Analysis
Accurate serum albumin testing requires careful sample collection and processing. Unlike some specialized tests, albumin measurement does not require fasting and can be performed with standard blood draw techniques.
Key testing considerations include:
- Preferred morning blood collection
- Use of serum or plasma specimens
- Sample stability at room temperature for up to 4 days
- Analytical methods like bromcresol green and immunoturbidimetric assays
Understanding Test Results
Interpreting serum albumin levels requires understanding age-specific reference ranges and potential interfering factors. Levels can vary significantly based on developmental stage, overall health, and individual physiological conditions.
Reference ranges for different age groups:
- Premature infants: 2.5-3.5 g/dL
- Term newborns: 3.0-4.2 g/dL
- Infants (1-12 months): 3.5-5.0 g/dL
- Children (1-15 years): 3.7-5.5 g/dL
Pediatric-Specific Insights
Albumin levels in children undergo significant variations during growth and development. These changes reflect the maturation of hepatic function and the body's evolving nutritional requirements.
Special considerations in pediatric populations include:
- Tracking growth and nutritional status
- Monitoring chronic disease progression
- Assessing developmental milestones
- Identifying potential metabolic disorders
Associated Medical Conditions
Abnormal albumin levels can indicate various underlying health conditions. Hypoalbuminemia, characterized by low albumin levels, can result from multiple primary and secondary causes.
Primary causes of low albumin include:
- Malnutrition
- Liver disease
- Nephrotic syndrome
- Chronic inflammatory conditions
Therapeutic Management
Effective management of albumin-related conditions requires a comprehensive approach. Treatment strategies focus on addressing underlying causes and supporting the patient's nutritional and metabolic needs.
Key monitoring and intervention strategies:
- Nutritional support and dietary modifications
- Targeted protein supplementation
- Management of underlying medical conditions
- Regular follow-up and diagnostic testing
