Lymphatic and Immune Systems

The spleen has a significant function.
The thymus is more active before puberty.
The thymus makes thymosine, which helps T lymphocytes mature and develop immunity.

MALT is found in the digestive tract, respiratory system, and anywhere with mucous membranes.
MALT constantly makes antibodies to fight off infectious agents (pathogens) and antigens.
Locations: lungs, urogenital system, respiratory system, digestive system

GALT is lymphatic tissue in the tonsils (part of the digestive system) and appendix (attached to the large intestine).
Tonsils and the appendix act as pathogen filters.
Inflammation of the appendix is called appendicitis; a ruptured appendix is a medical emergency

It's important to disconnect and use humor to cope with the seriousness of nursing.
Nurse humor can be odd, so sometimes it's best to keep it in your head.

Every time a baby is born, a lullaby plays.
The idea of playing "Another One Bites the Dust" when someone dies was deemed inappropriate.
"Knock, Knock, Knocking on Heaven's Door" was suggested as a more somber option.

Tonsils can be removed if they are constantly inflamed.
Tonsils play a small role in immunity, but their removal is sometimes necessary.
The appendix's function is not fully known, but it may have been important in early human development for fighting off foodborne pathogens.
If the appendix becomes inflamed (appendicitis), it is often removed.

Pain in the right lower quadrant of the abdomen is a hallmark sign of possible appendicitis.

Mononucleosis is a lymphatic disease associated with monocytes (page 386).
The virus infects B lymphocytes, which are immune lymphocytes.
Infected B cells spread through the bloodstream.
Mononucleosis used to be called the kissing disease because it is very infectious.

Ruptured appendix is a medical emergency.
Lymphoid tissues filter live and dead pathogens; inflammation indicates an infection.
Right lower quadrant pain is an urgent situation.
A ruptured appendix releases bacteria and pathogens into the peritoneal cavity.
The mucous membranes lining the peritoneal cavity absorb substances into the bloodstream.
A ruptured appendix can lead to sepsis (blood infection), which is a life-threatening emergency.
Harry Houdini reportedly died of a ruptured appendix.

The lymphatic system helps the body get rid of toxins, waste, and unwanted materials, including infections and cancer cells.
The system consists of thin tubes (lymph vessels) and lymph nodes or glands throughout the body.
The spleen, thymus, tonsils, and adenoids are part of the lymphatic system.
Lymph vessels have small, bean-shaped lymph glands. These glands can be felt in your neck, under your arm, and in your groin.
The lymphatic system carries a clear fluid called lymph.
As blood circulates, fluid passes into body tissues, carrying food to the cells.
This fluid bathes the tissues and collects waste products, bacteria, damaged cells, and cancer cells (if present).
The fluid drains back into lymph vessels and is transported to lymph glands which filter the lymph, removing harmful products. Lymph contains lymphocytes (white blood cells) that fight infections.
Lymph eventually reaches the thoracic duct at the base of the neck, which returns the filtered lymph to blood circulation.
Blockage, removal, or damage to lymph vessels or nodes can cause fluid buildup and swelling (lymphoedema).

The immune system consists of cells and tissues that protect against invading pathogens (foreign organisms or cells).
The immune system protects against improper transfusions and causes allergic reactions.

These prevent pathogens from entering or staying in the body.
Select all that apply questions on quizzes
Intact skin: The most important barrier to infection; emphasized in CNA training.
Mucous membranes: Secrete mucus, which carries pathogens out of the body. Mucous membranes secrete mucosal associated lymphatic tissue.
Body secretions:
- Mucus
- Tears: Wash away irritants.
- Sweat
- Discharge
Body reflexes:
- Coughing: Expels irritants from respiratory system.
- Sneezing: Expels pathogens; reason for wearing masks.
- Vomiting: Expels toxins from the upper digestive system.
- Diarrhea: Flushes out pathogens from the lower intestinal tract.

Responses if barriers are breached.
Phagocytes: Neutrophils, lymphocytes, and macrophages engulf and digest pathogens.
Natural killer cells: White lymphocytes that search and destroy pathogens; found in lymph nodes, spleen, bone marrow, and blood.
- These cells are responsible for attacking anything the bodies identifies as foreign and not a threat to the body.
- These cells don't respond to specific diseases.
Interleukins: Cause inflammation and fever when an invading pathogen is detected.
Interferons: Block viruses from infecting other cells.
Histamine: Made by mast cells, causes allergic reactions like redness and swelling (hives).
- Antihistamines (e.g., diphenhydramine/Benadryl) block mast cells and prevent histamine production.
- Diphenhydramine and Benadryl also cause sleepiness.
Prostaglandins: Activate pain receptors; work with histamines for inflammation and pain.
Complement: Made in the liver, activates mast cells to make histamine, kills pathogens, and stimulates phagocytes.

Occurs in response to allergens, infections, or injuries.
Involves dilating blood vessels and sending blood to the area for healing or pathogen elimination.

Increased heat: Blood is warm.
Redness: Hemoglobin in blood causes redness.
Swelling: Fluid accumulation in the area.
Pain: Complement releases pain-inducing substances.
Treatment: Anti-inflammatory drugs (NSAIDs) or steroidal anti-inflammatories (corticosteroids).

All these defenses occur anytime the body detects something that doesn't belong.
The goal is to fight off, get rid of, kill, or prevent multiplication of pathogens.