June 20, 2024

Rheumatoid arthritis is diagnosed through clinical, laboratory, and radiological features and are summarized through different protocols.

Diagnosis

American College of Rheumatology (ACR)-Criteria-1987

According to the American College of Rheumatology (ACR), Criteria-1987 diagnosis for RA required is 4 out of 7 below mentioned criteria should be there for more than 6 weeks at least

  1. Early morning Stiffness lasting for an hour
  2. Arthritis of three or four joints
  3. Small joints of the hand and foot should be involved
  4. Arthritis should be symmetrical
  5. Rheumatoid nodules should be better
  6. Positive RF test to be present
  7. Radiologically articular surface erosion and periarticular osteopenia should be there

The problem of this criteria is not intended to diagnose routine cases but used for research work

ACR/EULAR (European League against rheumatism) criteria

A score of >6/10 is needed to classify the patient as having definite RA

A. Joint Involvement

1 Large joint0
2-10 Large joints1
1-3 Small joints (with or without large joints)2
4-10 Small joints (with or without large joints)3
> 10 joints (at least 1 small joint)5

B. Serology (at least 1 test needed for classification)

Negative RF and negative ACPA (anticitrullinated protein antibodies)0
Low positive RF and low positive ACPA2
High positive RF and high positive ACPA3

C. Acute phase reactants (at least 1 test needed for classification)

Normal CRP and normal ESR0
Abnormal CRP and abnormal ESR1

D. Duration of symptoms

< 6 weeks0
>_ 6 weeks1

Investigations for RA

A. Laboratory test

  • Complete automated blood counts
  • Liver function test
  • Renal Function test
  • Urine analysis
  • Viral markers

Hypochromic Normochromic Anemia is frequently associated

B. Acute phase reactants

  • ESR and CRP are raised

C. Special test

Rheumatoid factor test:

It is a sensitive quantitative test but positive in 60-70% of patients

RA factor is an antibody that binds to Fc portion of IgG

Negative RA factor does not rule out RA, seronegative RA (Arthritis may be RA factor negative)

During 1st year of onset of the disease arthritis may be RA factor negative but later 70 % converts to positive

False-positive is seen in

  • Other Rheumatoid disease
  • Chronic infections
  • Sjogren’s syndrome

10% healthy population have positive RA factor, So this test is not very specific

Anti cyclic citrullinated peptides (Anti-CCP)

Anti-CCP is present in 70-80% of all RA patients, but rarely positive in non-RA patients

Specificity=95%

False-positive is seen in active tuberculosis

Anti-CCP can be positive in the early stage of RA or even before the onset of the disease

In early cases of RA, clinical symptoms are sometimes mild and non-specific and the patient may not fulfill even definite ACR criteria

In early RA, the presence of anti-CCP with or without positive RA factor may be associated with a more erosive disease that is aggressive in nature.

Anti-Nuclear Antibodies(ANA)

30-40 % of RA patients may have ANAs positive

Synovial Fluid Analysis

It helps to exclude other forms of arthritis as gouty infection

WBC Count: 5000-50,000/mm3

Rarely WBC exceeds 1,00,000/mm3 (Pseudoseptic)

MRI

MRI wrist may show tendinopathy; the earliest sign of RA

USG

Synovial thickening

Treatment Options

Treatment criterias for Rheumatoid arthritis
  • Conventional Therapy
  • Non-steroidal anti-inflammatory drugs
  • Disease-modifying anti-rheumatoid drugs
  • Corticosteroids
  • Biologicals

Corticosteroids are given in early RA and in a rheumatoid flare-up

Can be given to women, who develop RA in early pregnancy but again for a short duration

Extraarticular RA: Steroid + DMARDS

DMARDs should be started as early as possible to minimize joint damage

CBC, LFT, and RFT should be done prior onset of DMARDs

DMARDs usually take 3-6 months to act once started

History of pregnancy in young patients must be taken

Common Drugs:

Methotrexate (MTX)

Hydroxychloroquine (HCQs)

Sulfasalazine (SSZ)

Leflunomide (LEF)

A. Methotrexate (MTX)

The gold standard for mild and moderate cases

Inhibits dihydrofolate reductase (enzymes involved in DNA synthesis)

Both anti-inflammatory + Cytostatic effects

Low doses in RA, MTX from 7.5 mg/week to 25 mg/week slowly

The parental route is preferred due to better bioavailability and tolerability

Antiinflammatory effects of drugs usually appear after a minimum of 4-6 weeks

ADR: Bone marrow suppression, Liver toxicity,

The safety profile is increased by adding 1mg/day of folic acid

B. Sulfasalazine

Used alone in the mild form of RA or in contraindication to MTX

Effects come after 3-6 months of initial therapy

This molecule is linked to antibiotics known as sulfapyridine and with an antiinflammatory agent called 5-aminosalicylic acid

No teratogenic so safe in pregnancy

Doses: 1-2 gram/day

ADR: Dyspepsia, rashes, bone marrow suppression, and oligospermia

C. Hydroxychloroquine

In the mild form of RA

200-400 mg /day

The safe drug requires no monitoring

ADR: Headache, dyspepsia, and long-term usage leads to retinal changes

So, regular retinal checks should be done

D. Leflunomide

Very toxic but potent drug to treat RA

(Should not be used in young females)

Doses of LEF: 10-20 mg/day

Inhibits the enzyme involved in pyrimidine synthesis

Elimination can be increased by cholestyramine

ADR: diarrhea, hypertension, skin rashes. alopecia, liver toxicity

Combination therapy is used if results are not satisfactory with DMARDs

Biological

TNF Inhibitors

  • Infliximab
  • Adalimumab
  • Etanercept
  • Certolizumab
  • Golimumab

T-cell inhibitors

  • Abatacept

IL-6 inhibitors

  • Tocilizumab

B-cell depleting therapy

  • Rituximab

Cytotoxic therapies

  • Azathioprine
  • Cyclosporine

Physiotherapy and occupational therapy

Poor Prognostic factors in RA

  • Early erosive disease
  • Extraarticular involvement
  • Positive RF
  • Positive anti-CCP
  • HLA-DR4
  • Family history of RA
  • Persistent synovitis despite treatment
  • Persistently elevated ESR level / CRP level
  • Older age of onset of disease
  • Low socio-economic education level

EULAR recommendation for management of rheumatoid arthritis with synthesis and biological disease-modifying antirheumatic drugs -2019 update

See also: Rheumatoid arthritis(RA) of the cervical spine

See also: Rheumatoid Hand

See also: Rheumatoid Foot and Ankle deformities