Arthritis Lecture PDF

Arthritis By Dr. Basem Hassan Elesawy Professor of pathology Objectives: - Define arthritis - List types of arthritis - Describe the pathological picture of arthritis - Differentiate between different types of arthritis  Arthritis Definition: I...

Arthritis By Dr. Basem Hassan Elesawy Professor of pathology Objectives: - Define arthritis - List types of arthritis - Describe the pathological picture of arthritis - Differentiate between different types of arthritis  Arthritis Definition: It is an inflammation of the joint. Types: I) Acute: 1. Suppurative arthritis 2. Rheumatic arthritis 3. Traumatic arthritis II) Chronic: 1. Osteoarthritis 2. Rheumatoid arthritis 3. Hemophilic arthritis 4. Neuropathic arthritis (Charcot’s joint) 5. Syphilitic arthritis 6. Tuberculous arthritis 7. Gouty & pseudo - gouty arthritis  I- Acute Arthritis 1) Suppurative Arthritis Acute suppurative inflammation of the joints Organisms: 1. Streptococci 2. Staphylococci Age: Common in children. * In adults occurs usually with immunosuppression or I.V. drug abuse. Routes of infection: 1. Local spread: from adjacent septic condition as septic OM. 2. Hematogenous spread: from a distant sepsis. 3. Exogenous spread: from an opened infected wound. Pathology: (Acute suppurative inflammation) 1. Synovial membrane: Edema & congestion 2. Joint space & capsule: Collection of purulent exudate (pus) 3. Articular cartilages: Sloughing & destruction with exposure of bones Healing: 1- By granulation & scar tissue  fibrosis between the cartilaginous surfaces (fibrous ankylosis). 2. Then, bony fusion (bony ankylosis) & locked immobile joint & joint fixation occurs. Complications: 1- Local: - Narrowing of joint space - Stiff & painful joint - Local spread into peri-articular tissues (ligaments, tendons , muscles) 2- Systemic: - Toxaemia - Bacterimia & Acute Bacterial Endocarditis - Septicaemia - Pyemia  2) Rheumatic Arthritis Inflammation of the joint in rheumatic fever and usually associated with cardiac affection. Cause: Group A beta hemolytic streptococci as in upper respiratory tract infection as tonsillitis, pharyngitis (Immune response) Predisposing Factors: - Age: 5 - 15 years - Sex: M = F - Family history - Social conditions: Common in poor social classes  Pathogenesis: Abnormal immune response. Antibodies  against the strept. Ag cross-react with : - Collagen tissue in myocardium myocarditis - Joint C.T. glycoproteins  Rheumatic arthritis Evidences: 1. No PNL in the synovial fluid. 2. Rheumatic fever & arthritis occurs 2-3 weeks after the original streptococcal infection (post infection). Pathology: 1. Fleeting arthritis: It Starts in a proximal joint & leaves it without residual damage to affect another one either on the same or opposite side of the body. 2. Big joints usually affected the (Hip, Knee, Ankle, Shoulder & Elbow). 3. Redness, hotness & swelling (edema) of big joint usually the knee. 4. Fate : Complete resolution within few days without residual damage. Gross picture (N/E): The synovial membrane is : 1. Red due to capillary V.D. 2. Thickened 3. Granular with Aschoff nodules Microscopic picture (M/E): The synovial membrane shows Aschoff Immunologic Granuloma N/E: Oval or elongated nodules M/E: Fibrinoid necrosis in the center Chronic inflammatory cells mainly lymphocytes and histiocytes & Aschoff multinucleated giant cells Edema Fate : Complete healing without residual damage  II- Chronic Arthritis 1) Osteoarthritis (Osteoarthrosis) Chronic degenerative joint disease affecting the articular cartilage Sites: 1. Usually: Large joints particularly weight-bearing as hip & knee joints. 2. Occasionally: Small joints of hands & feet. Age: > 50 years due to abnormal wear & tear of the articular cartilage. Atherosclerosis, hypoxia Occupational ischemia Gross picture (N/E): 1. Articular cartilage: - Loss of luster - Patchy loss of cartilage 2. Subchondral bone: - Exposed highly polished surface - Thickened subchondral bone  form new bony outgrowths due to periosteal irritation  Osteophytes or spurs formation 3. Joint space: - Narrowing of joint space - Some of the marginal osteophytes break-off  loose bodies in the space * Osteoarthritis of the left knee 1- Osteophytes 2- Narrowing of the joint space 3- Increased subchondral bone density due to periosteal reaction In some areas synovial fluid enter inside bone  cystic appearance in x-rays. Microscopic examination (L/M): 1. Articular cartilage: - Becomes pink instead of bluish due to loss of muco-polysaccharide matrix. - Splits & fissures in the degenerated cartilage extend into its deeper layers. 2. The subchondral bone: - Thickened subchondral bone. - The osteophytes (Spurs) formation ( reactive new bone). 3. The Joint space: - It contains small foci of degenerated cartilage - Fibrous thickening of the synovial membrane &  2) Rheumatoid arthritis - Chronic, progressive, bilateral autoimmune disease. - It mostly damaging the joints, but it can also damage the heart, kidneys and eyes. Incidence: Very common, F > M (3-5 times). Age: 30-50 years old. It may be found in children (Still’s disease). Sites: Symmetric polyarticular arthritis Common: Small joints (hands ,feet, ankles, knees, wrists, elbows) Hand affection: Proximal interphalangeal and metacarpophalangeal joints are affected Distal interphalangeal joints are rarely affected Axial involvement: not common limited to the upper cervical spine hip joint : rare  Pathogenesis of Rheumatoid Arthritis -It is a generalized C.T. disease which cause: Chronic inflammation of the joint Proliferative synovitis Destroy articular cartilage &underlying bone Disabling arthritis Gross Picture (N/E): 1- Synovial membrane - Thickening of the synovial membrane: Change from thin, smooth synovial membrane  edematous with villous projections. - Increased vascularity due to angiogenesis. - Erosion of bone due to Increase osteoclastic activity. 2- Fibrous plates (Pannus growth) Extensive cartilage loss Exposed and pitted bones Pannus: fibrous connective tissue 3- Fibrous ankylosis -Pannus replaces the articular cartilage fibrous ankylosis - Needs physiotherapy 4- Bony ankylosis - Pannus(Fibrous C.T) extends to bony parts  Bony ankylosis (permanent deformity) - Needs joint replacement. Microscopic examination (L/M): Chronic non-specific inflammation 1. Synovial membrane: - Hyperplasia villous proliferation - lymphoplasmacytic infiltration - Edema 2. Articular Cartilage: - Fibrinoid necrosis - Swelling & fragmentation of the collagen Fiber 3. The proliferated synovial tissues : Form fibrous tissue( pannus) extending over the surface of articular cartilage. M/E: Pannus is formed of : Proliferating synovial cells +inflammatory cells+ granulation tissue+ fibrous connective tissue 4. Replacement of the articular cartilage by a fibrosis that unites the opposite bone causing fibrous ankylosis which ossifies changing into bony ankylosis. Clinical Course: It is highly variable In minority of patients:  the disease may become stabilized or may even regress. In majority of patients: chronic, remitting-relapsing course. After 15 to 20 years: the majority of patients develop deforming arthritis. Effects & Complications: A- Articular (joint) lesion: 1- Painful Fusiform swelling 2- Disfigured joint & Deformity 3- Limitation of movement of affected joint due to fibrous ankylosis 4- Immobile fixed joint due to bony ankylosis N.B: Joint morning Stiffness is the Early & Characteristic Sign of Rheumatoid Arthritis It is most noticeable in the morning and may not improve for hours & Sometimes it lasts throughout the day. 2-.Extra-articular lesions: - 1- Skin: Subcutaneous rheumatoid nodules Incidence: Occurs in 25% of cases Site: Extensors surface of arms N/E: They are firm, non tender, oval or rounded masses up to 2 cm in diameter M/E: Central area of fibrinoid necrosis of the collagen surrounded by chronic inflammatory cellular 2- Heart  Pancarditis 3- aorta  Aortic aneurysm 4- Blood Vessels  Necrotizing Vasculitis 5- Muscle  Muscle Atrophy 6- L.N  Lymphadenopathy & Splenomegaly 7- Lung  Fibrosis 8- Nervous system Neuropathy 9- Secondary Amyloidosis  Organs Failure Thank You & Good Luck