Diagnostic Testing

• Diagnostic Test
  • Used to determine a person's disease or condition based on signs and symptoms
  • Aids in planning treatment, assessing treatment effectiveness, and predicting prognosis

Laboratory Tests

• blood and urine tests.

Imaging Tests

• Mammography and CT scans

Endoscopy

• Colonoscopy and Bronchoscopy

Role of Diagnostic Tests

• Used to confirm or exclude suspected conditions after patient evaluation

Monitoring

• Additional diagnostic tests requested after a diagnosis to check treatment effectiveness

Prognosis

• Help in reviewing disease progression and predicting patient lifespan

Significance

• Aid patients in living longer and healthier lives when disease progression is delayed or halted
• Allow for early recovery through timely diagnosis and treatment implementation
• Give healthcare professionals information to choose appropriate preventive interventions and optimize care

Economic Significance

• Reduce hospitalization, decrease inappropriate medication use, shorten sick leaves, and improve health outcomes, enabling efficient use of resources

Importance of Following Test Diets

Accurate Results

• Body in optimal state for the diagnostic test

Clear Visualization

• Clear liquid or low-fiber diets improve visibility during medical imaging

Standardization

• Prescribed diets standardize testing conditions, reducing variables

Diagnostic Sensitivity

• Diets like fasting or nutrient challenges, test the body's response

Identification of Trigger Factors

• FODMAP elimination diets identify food triggers, for conditions like IBS

Enhanced Patient Safety

• Recommended diets minimize risks during medical procedures

Efficient Resource Use

• Adhering to test diets ensures efficient use of resources like time and equipment

The Healthcare Team

General Physician/Family Medicine Physician

• Initiates the diagnostic process
• Assesses the patient's overall health
• Determines the need for diagnostic tests

Specialist/Consulting Physician

• Provides specialized expertise
• Interprets test results

Radiologist

• Specializes in medical imaging
• Interprets results from X-rays, CT scans, and MRIs

Pathologist/Laboratory Medicine Specialist

• Oversees the laboratory
• Analyzes results from blood and tissue samples

Medical Technologist

• Performs laboratory tests

Nurse

• Assists in patient preparation
• Administers tests
• Monitors patients

Pharmacist

• Ensures medications are appropriate, safe, and effective, based on findings

Dietitian

• Offers dietary guidance, such as for glucose tolerance tests or other specific needs

Dietitian's Role in Diagnostic Diets

Assessment

• Assess medical history, nutritional status, and pre-existing conditions to understand specific needs

Customized Diet Plans

• Develop personalized plans tailored to specific tests, including specialized diets or fasting

Collaboration

• Works with healthcare team to align diets with treatment plans and medical goals

Patient Education

• Educates about test diets and provides instructions on foods, timing, and potential impacts on results

Monitoring and Follow-Up

• Monitors patients, addresses concerns, and evaluates impact of diet changes

Kitchen Service Collaboration

• Coordinates with kitchen services to ensure meals align with dietary needs

Patient Concerns

• Addresses questions related to test diet

Documentation

• Maintains records of dietary plans and responses, providing insights to the team

Colonoscopy

• Procedure involves examining the colon using a flexible tube

Dietary Requirements for Specific Tests

Clear Liquid or Low-Residue Diet

• Required for 1-3 days before colonoscopy

Lactose Tolerance Test

• Requires a lactose-free diet for 24 hours before the test, followed by consuming a lactose solution to evaluate digestion.

Oral Glucose Tolerance Test

• Includes overnight fasting followed by the consumption of a glucose solution, with blood samples collected at intervals.

Fasting Blood Glucose Test

• Involves overnight fasting, with no food or drinks except water.

GI Imaging (Barium Swallow/Enema)

• Requires clear liquid diet or specific restrictions to enhance imaging quality

Gluten-Containing Diet

• Must be continued before a Celiac Disease Test

Gastric Emptying Study

• Entails fasting for 8-12 hours
• Patients may consume a radiolabeled meal

Fecal Occult Blood Test (FOBT)

• Requires avoiding certain foods and medications before the sample collection

Hydrogen Breath Test

• Requires a specific diet the day before the test and overnight fasting
• Breath samples are collected after substrate consumption

Cardiac Stress Test

• Might require fasting, with specific caffeine instructions

Abdominal/Pelvic Ultrasound

• May require fasting

Magnetic Resonance Imaging (MRI)

• May require fasting, especially with contrast agents

Introduction on Blood Formation

Hematopoietic System

• A cell collection in bone marrow and lymphoid tissues
• Transports oxygen, nutrients, waste products, and hormones
• Contains regulatory buffers and plasma proteins
• Provides protection through antibodies and phagocytic activities

Reticuloendothelial System

• A system of fixed and free cells for immunological, cellular, and humoral defenses
• Responsible for phagocytosis and blood formation

Lymphoid Tissues

• Composed of lymphocytes and plasma cells in the spleen, mucous membranes, and the lining of the small intestine

Blood Components

Blood

• Fluid tissue composed of plasma and blood cells

Plasma

• Medium for transmission of nutrients and waste
• Contains albumin (for osmotic pressure), globulin (for antibodies), and fibrinogen (for coagulation)

Blood Volume

• Adult human body contains about 5L of blood, 7-8% of body weight
• Plasma constitutes 2.75L-3L

Types of Blood Cells - RBC

• Also known as erythrocytes

Characteristics

• Most prevalent blood cell; gives blood red color
• Outer envelope encloses hemoglobin a protein rich in iron and with oxygen affinity

Origin and Formation

• Originates in bone marrow
• Manufactures hemoglobin

Lifespan

• Lives for approximately 120 days
• Digested by phagocytic cells in the liver and spleen

Iron

• Most iron in hemoglobin is reclaimed for reuse
• Remainder is broken down into bile pigments, excreted by the liver

Function

• Deformable to fit through capillaries
• Aids carbon dioxide removal; CO2 enters the blood in the capillaries, returns to the lungs, and is exhaled

Enzyme

• Contains carbonic anhydrase, which speeds up the reaction of carbon dioxide and water

RBC Count

• 5,200,000 RBC per mm³ average is in males
• 4,600,000 RBC per mm³ average is in females

Volume

• RBC’s account for about 40-45% of blood (hematocrit)

Cell Ratio

• Normal blood has a ratio of 600 RBCs for each white blood cell and 40 platelets

White Blood Cells (WBC)

Leukocytes

• Less numerous compared to RBCs
• Approximate ratio of 1:700

Volume

• Average of 7000 WBC per microliter of blood in adults

Role

• Part of the immune system, reacts to injury and protects against foreign cells

Circulation

• Circulate in the blood for transport to infection areas

Protection

• Provides protection by phagocytosis, antibody production, and rejection of foreign tissues

Nuclei

• They have nuclei

Monocytes

• Enter the tissue, enlarge, and become macrophages

Macrophages Function

• Phagocytize bacteria and destroy old, damaged, and dead cells

Where

• Macrophages are found in the liver, spleen, lungs, lymph nodes, skin, & intestine

Monocytes Circulation

• Stay in the blood for 10-20 hours

Macrophages

• Become tissue macrophages that live for months to years

Lymphocytes Circulation

• Pass between lymph tissue, fluid, and blood

Lymphocytes

• Remain in the blood for several hours, and can live for weeks, months, or years

Neutrophils and Monocytes

• Use diapedesis, chemotaxis, and phagocytosis

Lymphocytes

• Complex cells that direct the immune system

T Cells

• Cell-mediated immunity
• 75% of lymphocytes; recognize and "remember" foreign invaders

B Cells

• Humoral immunity, produce antibodies

Complement System

• Helps antibodies and components destroy invading antigens

Plateletes Thrombocytes

• Maintain vascular integrity
• Help with blood-clotting

Number

• Average count is 250,000 in each microliter of blood

Formation

• Formed in the bone marrow from megakaryocytes

Megakaryocytes action

• Break up into platelets

Nucleus & Reproduction

• These do not have nucleus, and do not reproduce

Lifespan

• These lasts approximately 10 days

Blood Disorders

Anemia

• A decrease in the circulating RBC mass and oxygen-carrying ability of the blood

Hemoglobin

• The level is below normal for age and gender

Hemoglobin Levels (WHO)

• Below 12g/100ml (women and children ages 6-14 years) - Below 13g/100ml (men) - Below 11g/100ml (children ages 6 months to 6 years)

Pregnancy Hemacrit

• Hematocrit is below 34% for pregnant women

Origin

• Can be acquired/hereditary

Nutrient-Related Anemia

• Due to lack of nutrients for blood formation

Nutrients

• Includes iron, vitamin C, E, protein, B12, folic acid, B6, copper, and riboflavin

Dietary Problem

• Common problems associated with anemia are iron, protein, folic acid, B12, and vitamin C deficiencies

Changes

• Changes in riboflavin and vitamin E have links to anemia development and control

Nutritional Anemia: Iron Deficiency

IDA Etiology

• Occurs when the body doesn't have enough iron to produce hemoglobin
• Hemoglobin is RBC substance that carries oxygen

IDA Manifestations

• Fatigue is an initial symptom
• Weakness, pale skin, shortness of breath, dizziness, headache, cold extremities, and brittle nails

IDA Nutrition

• Increase heme (animal sources) & non-heme (plant sources) iron intake
• Consume foods high in vitamin C
• Can consume iron supplements

Nutritional Anemia: Vitamin B12 Deficiency - Pernicious Anemia

Vitamin B12 Etiology

• Caused by lack of intrinsic factor
• Intrinsic factors is needed to absorb Vitamin B12 in the intestine
• Autoimmune Destruction of the stomach cells; affecting stomach or small intestine

Vitamin B12 Manifestations

• Fatigue, weakness, pale skin
• Tingling, numbness in hands and feet
• Glossitis
• Difficulty walking
• Memory Loss
• And Mood Changes

Anemia: Folate Deficiency

Etiology

• Can result from inadequate dietary intake
• Impaired absorption or increased demand

Manifestations

• Fatigue, weakness and pale skin
• Shortness of breath
• Irritability
• Can be associated to neural tube defects
• Mouth Sores

Anemia: Copper Deficiency Anemia

Etiology

• Occur due to inadequate dietary intake, impaired absorption, or excessive zinc intake.

Manifestations

• Fatigue, weakness and pale skin
• Shortness of breath
• Neurological symptoms

Copper Rich Foods

• GLV
• Citrus Fruits
• Beans
• Lentils

GLV

• Liver
• Fish
• Citrus fruits
• Copper rich foods

Etiology

• Lack intake of Vitamin A
  • Due to malnutrition

Manifestations

• Fatigue
• Weakness
• Pale Skin
• Decreased immune functions

Vitamins A rich foods

• Beef
• Poultry
• Fish

Non-Nutritional Anemia: Aplastic Anemia

Etiology

• Occur when bone marrow fails to produce RBC’s, WBC’s an Platelets

Hemolytic Anemia

Etiology

• Destruction of RBCS are faster than they can be produced

Parasite Anemia

Etiology

• Occur when parasites infect the body and feed on RBC’s.
• Malaria
• Hookworm

Manifestations

• Pale skin
• Fever

Sickle Cell Anemia

Etiology

• A genetic disorder causing a mutation when the hemoglobin mutates and it causes the RBCs to be sickle shaped and rigid.

Etiology

Thalassememia

• Group of inherited disorders characterized by reduced abnormal homoglobin

Iron Overload and Hemochromatosis

What to eat

• Reduce the absorption of iron from your diet and the dietary
• By avoiding iron rich food

Thrombocytopenia

• Characterized by low platelet count leading to blood clotting and internal bleeding.

Polythemia Vera

• Is a blood disorder caused by the overproductio of red blood cells

The food that you eat affect cancer

• Foods like the anti - oxidant nutrients
• The ones affecting the metabolism and cell development
• Foods affect the speed of damaged sells