Here is a discussion of laboratory diagnosis of rheumatoid arthritis and how to monitor that disease plus Markers of active-diseases and how to monitor side effects of drugs.
Diagnosis includes also clinical picture of rheumatoid arthritis.
Investigations
1- Blood
• Normocytic normochromic anemia (anemia of chronic disease) or hypersplenism.
Iron deficiency anaemia due to chronic blood loss,(NSAID).
• WBCs: +++ in acute phase.
if Low : suspect Felty's syndrome
• Platelets +++ (phase reactants), --- with felty's syndrome.
2- ESR
• + In active stage.
• +++ In severe cases.
• Normal with treatment and remission.
3- C-reactive protein : parallel with ++ ESR
• ++ c-reactive rotein • Thrombocytosis .
4- Serology
• Rheumatoid factor (RF) positive in 80 % of cases.
• ANA positive in 20 % of cases (non specific).
• Anti-DNA : negative
• Recently Anti CCP (cyclic citrullinated peptide antibodies) are present in up to 80% of patients with RA with 90% specificity.
They can detect early disease when RF is negative. CCP can predate the disease by several years.
• Normal complement level.
5- Synovial fluid
• -- protein, -- glucose, -- Complement.
• Also it is cloudy with increased white cell count.
6- X-ray
• Early : - Soft tissue swelling. - Periarticular osteoporosis.
- Narrow joint space (due to destruction of cartilage)
• Late : - Bony ankylosis + deformity.
7· Other investigations
• Synovial biopsy.
• U/S - C.T scan - MRI for joint involvement.
. • X-ray • Acute phase reactants
• Morning stiffness. • Acute phase reactants
• Blood chemistr e. kidne functions.
Diagnosis includes also clinical picture of rheumatoid arthritis.
Investigations
1- Blood
• Normocytic normochromic anemia (anemia of chronic disease) or hypersplenism.
Iron deficiency anaemia due to chronic blood loss,(NSAID).
• WBCs: +++ in acute phase.
if Low : suspect Felty's syndrome
• Platelets +++ (phase reactants), --- with felty's syndrome.
2- ESR
• + In active stage.
• +++ In severe cases.
• Normal with treatment and remission.
3- C-reactive protein : parallel with ++ ESR
Markers of active-diseases (activity) :
•.++ ESR • -- Hb• ++ c-reactive rotein • Thrombocytosis .
4- Serology
• Rheumatoid factor (RF) positive in 80 % of cases.
• ANA positive in 20 % of cases (non specific).
• Anti-DNA : negative
• Recently Anti CCP (cyclic citrullinated peptide antibodies) are present in up to 80% of patients with RA with 90% specificity.
They can detect early disease when RF is negative. CCP can predate the disease by several years.
• Normal complement level.
5- Synovial fluid
• -- protein, -- glucose, -- Complement.
• Also it is cloudy with increased white cell count.
6- X-ray
• Early : - Soft tissue swelling. - Periarticular osteoporosis.
- Narrow joint space (due to destruction of cartilage)
• Late : - Bony ankylosis + deformity.
7· Other investigations
• Synovial biopsy.
• U/S - C.T scan - MRI for joint involvement.
Monitoring of Rheumatoid Arthritis
To establish diagnosis :
• Clinica criteria • Serological tests. • X-ray • Acute phase reactants
To monitor disease activity and drug efficacy :
• Pain • Joint tenderness• Morning stiffness. • Acute phase reactants
To monitor disease damage:
• X-ray • Functional assesmentTo monitor side effects of drugs (drug safety):
• Urine analysis • Blood picture.• Blood chemistr e. kidne functions.