Internal medicine Flashcards
RA definition, aetiology(A++), pathogenesis and C/P?
Definition:
Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease primarily involving the synovial joints. Most commonly, the wrists and small joints of the hands & feet are involved, on both sides of the body.
Aetiology:
There is no specific etiology. BUT there is a combination of genetic, infectious and environmental factors.
1- Genetic factor:
o The association of RA and the human leukocyte antigen (HLA antigens DR1 and DR4) is well established.
o Also, RA patients possess HLA DR2 considered an indicator of good prognosis.
o Seropositive erosive severe diseases are more likely associated with HLA DR3.
o There is a higher prevalence of RA in the first-degree relatives and in monozygotic twins.
2-Infectious agents:
o Microbes are the most common triggering agents of the disease in genetically predisposed individuals.
o Many bacterial organisms such as diphetroid and mycoplasma are claimed.
o Also, viruses such as Epstein Barr virus are considered as a potential etiologic agent for RA.
3-Hormonal factor:
o Higher incidence of the disease occurs in female about (70%).
o The incidence is lower in females taking contraceptive pill, also remissions of disease activity occur in pregnancy due to the immunosuppressive effect of alpha 2 glycoprotein and the immune modulating properties of female sex hormones.
4- Auto immunity:
RA is one of the autoimmune diseases in which the antibodies are produced against normal IgG of self, such as rheumatoid factor (RF) and Anti- Cyclic Citrullinated Peptide (CCP) antibodies.
Pathogenesis:
One or several antigens will activate T cells. Clonal expansion of T cells will drive B lymphocytic proliferation and production of antibodies including rheumatoid factor (RF).
This immunological event causes inflammation of the synovial membrane (synovitis).
So, the synovial membrane becomes thickened, hyperplastic, hyperaemic, oedematous and proliferates to form villi filling the joint space, producing (Pannus), which releases damaging chemicals into synovial fluid so, erode the cartilage.
C/P:
- Onset:
o Insidious
o acute precipitated by physical trauma
o palindromic.
-Pattern of onset:
o Monoarticular
o Pauciarticular
o Oligoarticular
o Polyarticular
-Course:
o Progressive
o Regressive
o Remission and exacerbation
- Presentations:
Articular manifestations: affection of peripheral joints in a symmetric pattern.
Extra-articular involvement of organs such as the skin, heart, lungs, and eyes can be significant.
Constitutional symptoms, including fatigue, malaise, and morning stiffness
Morning stiffness: Difficulty in movements of joints due to accumulation of inflammatory metabolites at night due to immobilization of joints.
RA extra- articular manifestations Clinical picture? (A+++)
1-Rheumatoid nodules:
o They occur in 15-20% of RA patients, usually subcutaneous over the extensor surface of elbow, over bony prominences such as head, sacrum and Achilles tendon.
o They are usually mobile but they may be bound to the periosteum.
o They may be single or multiple, may decrease in size with treatment but do not disappear.
o They are associated with positive rheumatoid factor and their presence indicate poor prognosis.
o They may appear around fingers called intra-cutaneous and even may appear in the internal organs such as heart, lung.
2-Anaemia:
It is present in patients with active RA. It’s usually normocytic normochromic anaemia. It may occur as a result of blood loss or marrow suppression by drugs or as a part of Felty’s syndrome (variant of RA).
3-Lymphadenopathy:
The nodes are soft, mobile non tender (one or two).
if it is associated with splenomegaly, anaemia, positive RF and leukopenia, lymphadenopathy is diagnostic for Felty’s syndrome.
4-Osteoporosis:
o Early localized periarticular osteoporosis.
o Late generalized osteoporosis as a result of immobilization and drugs.
5-Eye involvement:
In the form of:
Episcleritis (common and self-limiting),
Keratoconjunctivitis sicca (Sjogren’s syndrome),
Scleritis occur in severe systemic RA with vasculitis.
6-Lung involvement:
Lung affection is a common in RA, in the form of:
*Pleurisy, pleural effusion.
*Rheumatoid nodules in the lung. *Interstitial fibrosis.
*Rheumatoid pneumoconiosis (Caplan’s syndrome).
7-Heart involvement:
in the form of pericarditis, pericardial effusions, nodules in the conducting system and on the valves.
8-Neuromuscular involvement
9-Renal and liver involvement
RA lab investigations and Imaging + ACR criteria (A+++) ?
Laboratory Investigations:
-Complete blood picture (CBC).
-Erythrocyte sedimentation rate (ESR).
-C-reactive protein (CRP).
-Rheumatoid Factor:
Detected by latex fixation test or Rose wooler method. Positive in 75-80% of RA patients but can be only detected in 5 % of normal population,
Its titre may decrease with the improvement of the disease activity, but it never turn negative.
- Anti- Cyclic Citrullinated Peptide (CCP) antibody:
It has high diagnostic specificity for RA and used in the new criteria for diagnosis of early RA.
It provides prognostic information on the severity of the disease.
Imaging:
X-ray of the hand in RA
American College of Rheumatology (ACR) criteria for the diagnosis of RA:
1. Morning stiffness
2. Arthritis of 3 or more joint areas, observed by a physician.
3. Arthritis of hand and wrist joints
4. Symmetric arthritis
5. Rheumatoid nodule
6. Serum Rheumatoid Factor
7. Radiographic changes hand and wrist radiographs–erosions or juxta-articular osteopenia
Differential diagnosis of joint pain in childhood? (A++)
The broad differential diagnosis can be remembered with the
mnemonic PRIME BONE PAN:
P—Pharmacologic: serum sickness; drug-induced lupus
R—Rheumatologic: juvenile idiopathic arthritis; systemic lupus erythematosus (SLE); Sjögren’s syndrome; systemic sclerosis/mixed connective tissue disease (MCTD); vasculitis; dermatomyositis; sarcoidosis
I—Infectious/postinfectious: bacterial (osteomyelitis, discitis, septic arthritis, rheumatic fever, reactive arthritis); viral (“toxic/transient” synovitis, human immunodeficiency virus [HIV], hepatitis B [Hep B] or hepatitis C [Hep C], parvo, Epstein–Barr virus [EBV], Herpes, rubella vaccination)
M—Metabolic/genetic: mucopolysaccharidoses; mucolipidoses; heritable collagen disorders (Marfan, etc.); pseudorheumatoid chondrodysplasia
E—Episodic: autoinflammatory syndromes (FMF and other periodic fever syndromes).
B—Blood/hematologic: sickle cell anemia; hemophilia
O—Orthopedic: chondromalacia patellae; Osgood–Schlatter disease; osteochondritis dissecans; Legg–Calve Perthes disease; slipped capital femoral epiphysis
N—Neoplastic: neuroblastoma; leukemia/lymphoma; bone tumors; metastases.
E—Endocrine: hypercortisolism; hypothyroidism; rickets; diabetes mellitus
P—Pain amplification syndromes/psychosomatic: complex regional pain syndrome (CRPS); fibromyalgia.
A—Accidental/trauma
N— “Normal variants”: “growing pains”; benign hypermobility
Signs and symptoms of JIA, Physical findings (A++)
A. History findings in children with JIA may include the following:
1. Arthritis
» present for at least 6 weeks before diagnosis (mandatory for diagnosis of JIA)
2. Either
» insidious or abrupt disease onset,
» often with morning stiffness.
3. Complaints of
a. joint pain,
b. swelling,
c. limited range of motion.
4. History of
a. school absences
b. or limited ability to participate in physical education classes
5. Spiking fevers
» occurring once or twice each day at about the same time of day
6. Evanescent rash (transient and disappears rapidly) on the trunk and extremities
7. Psoriasis, dactylitis, enthesitis, or inflammatory back pain
B. Physical findings include the following:
1. Arthritis:
» Defined either as intra-articular swelling on examination
» or as limitation of joint motion in association with pain.
- Iridocyclitis
» The most common comorbidity.
» (inflammation of the anterior chamber and anterior vitreous) that is typically asymptomatic but sometimes causes blurring of vision and miosis.
» Rarely, in enthesitis related arthritis, there are also the more common uveitis manifestations of conjunctival injection, pain, and photophobia.
» Iridocyclitis can result in scarring (synechia), - cataracts,
- glaucoma,
- or band keratopathy.
» Iridocyclitis is most common in oligoarticular JIA, developing in nearly 20% of patients, especially if patients are positive for antinuclear antibodies (ANA).
» It may occur in the other forms but is exceedingly rare in - polyarticular RF-positive JIA
- and systemic JIA.
- Skin abnormalities
» present mainly in psoriatic JIA, in which psoriatic skin lesions, dactylitis, and/ or nail pits may be present, and in systemic JIA, in which a typical transient rash often appears with fever. - Systemic abnormalities
б in systemic JIA include - high fever, 2. rash, 3. splenomegaly,
- generalized adenopathy (especially of the axillary nodes),
- serositis with pericarditis or pleuritis.
б These symptoms may precede the development of arthritis.
б Fever occurs daily (quotidian) and is often highest in the afternoon or evening and may recur for weeks.
б In 7 to 10% of patients, systemic JIA may be complicated by macrophage activation syndrome, a life threatening cytokine storm syndrome.
Osteoarthritis risk factors?
- Age
- Female versus male sex
- Obesity
- Lack of osteoporosis
- Occupation
- Sports activities
- Previous injury
- Muscle weakness
- Proprioceptive deficits
- Genetic elements
- Acromegaly
- Calcium crystal deposition disease
Osteoarthritis classification ?
Primary Osteoarthritis:
б Localized or generalized forms
б Localized OA most commonly affects:
» the hands
» feet
» knee
» hip
» spine
б joints less commonly involved:
» shoulder
» temporomandibular
» sacroiliac
» ankle
» and wrist joints
б Generalized OA: three or more joint sites.
Sites typically involved in 1ry OA:
1. DIP
2. PIP
3. 1st CMC (Carpometacarpal joint)
4. Acromioclavicular
5. Hips
6. Knees
7. 1st MTP
8. Facet joints of cervical and lumbar spines
Secondary Osteoarthritis:
б This type of OA is caused by other factors, but the resulting pathology is the same as for primary OA:
1. Congenital disorders of joints
2. Obesity
3. Diabetes.
4. Inflammatory diseases (Gout and RA)
5. Injury to joints,
6. Septic arthritis (infection of a joint)
Mechanical LBP vs Inflammatory LBP?
