15.11.6.1 Rheumatology - Connective Tissue Disease Flashcards
Define paediatric rheumatic disease
- Paediatric Rheumatic Diseases is a term used to describe many auto-immune and auto-inflammatory conditions that can develop in children and adoloscents.
- Although they share many symptoms including joint inflammation (pain, joint swelling, redness and warmth), each rheumatologic condition is distinct.
- Not all Paediatric rheumatic disease affects just the musculoskeletal system but can also involve the eyes, skin, muscles, respiratory and gastrointestinal tract as well
Embryonic development: 3 germ layers
- ectoderm
- mesoderm
- endoderm
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Ligamnet vs tendon vs Cartilage
Ligament
- bone to bone
- injuries take time to heal
Tendon
- muscle to bone
Cartilage
- flexible
- at end of bone
- cushions
Slides
Joints
- human body has 350 joints
- types
Muscles
Muscles of the body allow movement to occur at joints.
• Muscles have to work in pairs to move
JOINTS e.g. elbows and knees.
• Elbows: Bicep and triceps pairing
• Knees: Hamstring and quads pairing
• Muscle contraction and relaxations create movement
Innate and adaptive immunity
THE INNATE IMMUNE SYSTEM: “hard-wired” defense that has evolved over millions of years to recognize pathogens that commonly infect humans. Responds the same way on repeat exposure. Recognizes patterns. Rapid protection. Hours to days.
• Complement and cytokines; Professional phagocytes (macrophages, monocytes, neutrophils) and antigen; Presenting cells; Natural killer cells.
THE ADAPTIVE IMMUNE SYSTEM: protects against almost any invader. Adapts to antigen to be more specific. Memory.
• Slower response over days to weeks.
• Humoral immunity - B-cells, plasma cells and antibodies; Cell mediated immunity - T-cells
Central and peripheral tolerance
Central tolerance: is a mechanism of tolerance to self antigens in the bone marrow and thymus, which eliminates potentially self-responsive lymphocytes before they have completed their maturation
Peripheral tolerance: Inactivation or elimination of lymphocytes that have matured and recognize self and occurs in secondary (peripheral) lymphoid organs or peripheral tissues (e.g. spleen, lymph nodes, liver, GIT)
Auto immunity
Loss of immunological tolerance
Risk factors for auto-immunity
Innate immune responses
• Inflammation: a tissue reaction that delivers mediators of host defense-circulating cells and proteins-to sites of infection and tissue damage
• Accumulation and activation of leukocytes and plasma proteins at sites of infection or tissue injury. These cells and proteins act together to kill mainly extracellular microbes and to eliminate damaged tissues.
• Auto-inflammation: inflammation of self tissues directed by the innate immune system.
Auto-inflammation and auto0inflammatory conditions
- Relatively new and expanding group of diseases.
- Inflammation directed against self.
- Predominantly innate immune system.
- Characterized by inflammatory episodes at disease-prone sites, in the absence of auto-reactive T cells or significant autoantibodies.
- Examples: systemic Juvenile Idiopathic Arthritis (s JIA)
Auto- inflammation vs Auto-immunity
Unique challenges facing children with JIA in SA
- TB and HIV change spectrum of disease presentation
- Malnutrition
- Poverty
- Poor access to health care and delays in diagnosis
- Shortage of Paediatric Rheumatologists in the country
- Covid
In which organs does JIA present in and affect?
Common presenting symptoms of JIA
