Lymphatic System Overview

Lymphatic System

Defends against disease and infection.

Lymph

Fluid carrying white blood cells

Lymph Vessels

Transport lymph

Lymph Nodes

Filter lymph, produce lymphocytes

Lymphatic Tissue

Includes spleen, thymus, tonsils, etc.

Pathogens

Microorganisms that cause disease

Protozoa

Waterborne, animal-like (e.g., Malaria)

Helminths

Parasitic worms (e.g., Tapeworm)

Rickettsiae

Insect-transmitted parasites (e.g., Typhus)

Direct Contact

Person-to-person, food/water

Indirect Contact

Coughing, sneezing, insects, air, animals

Spleen

Produces lymphocytes, recycles old blood cells, stores blood

Thymus Gland

Trains and matures T-lymphocytes

Lymph Nodes

Filter harmful substances, produce lymphocytes

Tonsils

Filter bacteria (tonsils, lingual, adenoids)

Immunity

Defense against pathogens

Anigten- Anitbodies Reactions

Specific reactions to antigen by antibodies.

Nonspecific Defense

General (skin inflammation)

Specific Defense

Involves specialized cells (T-cells, B-cells, Macrophages)

Marcophanges

Large white blood cells that engulf and digest pathogens and cellular debris.

Helper T cells

Identify threats.

Killer T cells

Destroy cancer cells

B cells

Produce antibodies and memory cells

Natural Immunity

Inherited immunity that provides a first line of defense against pathogens.

Active

from disease recovery of vaccination

Passive

Antibodies for external source (vaccinations)

Immunizations

Artificial immunity via vaccinations

Adenitis

• Cause: Lymph node infection

• Symptoms: Fever, swollen/painful nodes

• Treatment: Antibiotics, warm compresses, drainage

Hodgkin’s Disease

• Type: Cancer of lymph nodes

• Symptoms: Painless swelling, fever, night sweats, weight loss

• Treatment: Chemotherapy, radiation

Lymphangitis

• Cause: Infection in lymph vessels

• Symptoms: Red streaks, fever, tenderness

• Treatment: Antibiotics, rest, elevation

Splenomegaly

• Cause: Infection, liver disease

• Symptoms: Enlarged spleen, abdominal pain

• Treatment: Sometimes requires splenectomy

Tonsillitis

• Cause: Tonsil infection

• Symptoms: Throat pain, fever, visible spots

• Treatment: Rest, possible antibiotics