Assessment and Overview of Immune Function

Flashcards covering immune system components, inflammatory response steps, leukocyte differentiation, SIRS criteria, acquired immunity types, and clinical assessment techniques.

What is the definition of immunity?

The body's ability to resist infection and disease.

Which components constitute the body's first line of defense?

Skin, mucous membranes, and secretions of skin and mucous membranes.

Which components make up the body's second line of defense?

Inflammatory response, interferons, phagocytosis, and complement.

What are the primary and secondary lymphoid organs of the lymphatic system?

Primary lymphoid organs are the thymus and bone marrow. Secondary lymphoid organs are the spleen, lymph nodes, and tonsils/adenoids.

What are the percentages and primary functions of neutrophils and monocytes?

Neutrophils ($55-70\%$) serve as the first line of defense with phagocytes that destroy bacteria. Monocytes ($5-6\%$) phagocytize and ingest engulfed microorganisms.

What role do lymphocytes and eosinophils/basophils play in leukocyte differentiation?

Lymphocytes ($30-40\%$), comprising B cells and T cells, orchestrate adaptive immune responses. Eosinophils and basophils ($1-2\%$) respond in allergic reactions.

What physiological events occur during the inflammatory response?

Injured body cells release cytokines (histamine), capillaries dilate, pyrogens reach the hypothalamus raising temperature, pain receptors are activated, and WBCs flock to the infected area.

What are the four sequential steps of the inflammatory response shown in this diagram?

1. Damaged tissues release histamines, increasing blood flow to the area. 2. Histamines cause capillaries to leak, releasing phagocytes and clotting factors into the wound. 3. Phagocytes engulf bacteria, dead cells, and cellular debris. 4. Platelets move out of the capillary to seal the wounded area.

What are the five cardinal signs of inflammation?

Erythema, heat, edema, pain, and drainage.

What are the clinical diagnostic criteria for Systemic Inflammatory Response Syndrome (SIRS)?

Temperature $< 96.80$ or $> 100.40$, HR $> 90\,\text{beats per minute}$, RR $> 20\,\text{breaths per minute}$ or paCO2 $< 32$, and WBC $< 4000$ or $> 12{,}000$ or $10\%$ bands.

What formula defines sepsis and what are its common sites of origin?

SIRS + Infection = Sepsis. Common sites of origin are the urinary tract, GI system, respiratory tract, and skin & wounds.

According to this flowchart, what are the four classifications of acquired immunity and their definitions?

1. Naturally acquired active: Infection; contact with pathogen. 2. Naturally acquired passive: Antibodies pass from mother to fetus via placenta; or to infant in her milk. 3. Artificially acquired active: Vaccine; dead or attenuated pathogens. 4. Artificially acquired passive: Injection of immune serum (gamma globulin).

How does this artwork visually distinguish active immunity from passive immunity?

Active immunity is illustrated by immune memory/infection (natural) or a vaccine syringe (artificial), whereas passive immunity is illustrated by maternal transfer to an infant (natural) or a bottle of serum (artificial).

What key areas are assessed during the physical examination of the immune system?

Inspection of nodes, skin, and body temperature; Auscultation of lungs and heart; Palpation/Percussion of nodes, abdominal, and joints.

What diagnostic studies are utilized when evaluating the immune system?

Blood tests (CBC with differential, Erythrocyte sedimentation rate, C-reactive protein, Antibody production), Skin tests (Delayed hypersensitivity skin test, Tissue allergy panel), and Radiologic imaging (CT, MRI, ultrasound, PET).