Rheumatology

• Intraarticular pathology

  Involves synovium, hyaline cartilage, intraarticular joint capsule
• Extraarticular pathology


  Involves ligaments, tendons, muscle, fascia
• Localization of Disease in Rheumatology


  1. Step 1. Intraarticular vs extraarticular pathology

  2. Step 2. Intraarticular pathologies: Synovitis vs Articular cartilage involvement

  3. Step 3. In Synovitis: a. Only Synovitis, b. Spondyloarthritis, c. Crystal arthropathy
• Synovitis


  • Seen in RA, SLE, SLE like arthritis (Sjogren's/polymyositis/dermatomyositis)
  • Jaccoud's arthropathy also seen in acute rheumatic fever
  • Erosive & Non erosive arthritis
• Articular cartilage involvement


  • Seen in Osteoarthritis
  • Loss of joint space, Osteophytes, Subchondral sclerosis
• Rheumatoid arthritis


  • Erosions seen as juxtaarticular osteopenia
  • Deformity due to erosions
• SLE/SLE like arthritis


  • Erosions not seen
  • Non erosive deformity due to laxicity (Jaccoud's arthropathy)
• Spondyloarthritis (SpA)


  • Synovitis + Enthesitis + Dactylitis
  • Axial predominant SpA: Ankylosing spondylitis
  • Peripheral predominant SpA: Reactive arthritis, Psoriatic arthritis
• Crystal arthropathy


  • Synovitis due to crystals
  • Monosodium urate monohydrate crystal (MSUM)/Gout: 1st MTP > Knee joint
  • Calcium pyrophosphate dihydrate crystal (CPPD)/Pseudogout: Knee joint
• Symmetrical polyarthritis of small joints of upper limb

  • Acute (<6 weeks): Post viral (parvovirus B19), Undifferentiated arthritis
  • Chronic (>6 weeks): Rheumatoid arthritis, SLE/SLE like arthritis, Psoriatic arthritis
• Rheumatoid arthritis


  • Chronic inflammatory multisystem autoimmune connective tissue disease
  • Peak: 40-60 yrs
  • Female:male ratio 3:1
  • 2nd most common connective tissue disorder: Sjogren's syndrome
  • Most common arthritis: Osteoarthritis
• Symmetrical polyarthritis vs Asymmetrical oligoarthritis

  • Symmetrical polyarthritis (>5 joints): Rheumatoid arthritis
  • Asymmetrical oligoarthritis (2-4 joints): Psoriatic arthritis, Reactive arthritis
• Erosive arthritis vs Non erosive arthritis

  • Erosive arthritis: Rheumatoid arthritis, Psoriatic arthritis, Chronic crystal arthritis (MSUM > CPPD), Multicentric reticulohistiocytosis, SLE & SLE like arthritis
  • Non erosive arthritis: Acute rheumatic fever, Acute crystal arthritis, Relapsing polychondritis (RPC)
• Etiology of Rheumatoid Arthritis

  • Environmental & genetic factors -> abnormal protein modification (citrullination)
  • Abnormal proteins -> presented by APC to T cells -> activation of B cells & neutrophils -> Migration to joint
  • Synovial hypertrophy -> Pannus formation -> Bone erosion
• Genetic factors in Rheumatoid Arthritis

  • HLA associated factors: HLA-DRB1*04 (QKRAA amino acid motif), HLA-DRB1*13 (protective)
  • Non HLA associated factors: PADI-4, PTPN 22
• Environmental factors in Rheumatoid Arthritis

  • Smoking: Strongest risk factor, associated with bad prognosis, increases risk of ILD, increases expression of PADI-4 in airway
  • Infection: Chronic periodontitis caused by Porphyromonas gingivalis
  • Alcohol/OCP: Mild protection
• Autoantibodies in Rheumatoid Arthritis

  • Anti CCP/anti citrullinated polypeptide/mutated citrullinated vimentin: Seen in 80-90% cases, 95% specific for RA, best marker for preclinical infection, associated with higher risk of extrarticular features
  • Anti CarP: Associated with palindromic rheumatism
  • Rheumatoid factor (RF): IgM directed against Fc portion of IgG, higher titre associated with higher disease activity, 75-80% specific
• Articular manifestations of Rheumatoid Arthritis

  • Duration > 6 weeks, Bilateral symmetrical, Intraarticular, Inflammatory (morning stiffness > 45 mins), Peripheral small joint, upper limb polyarthritis, Disease starts at distal radioulnar joint
• Joints involved in Rheumatoid Arthritis

  • Involved: MCP, Wrist, PIP, C-spine
  • Spared: DIP, 1st CMC, 1st MTP, Thoracolumbar & sacral spine
• Reversible deformities in Rheumatoid Arthritis

  • Zigzag deformity, Subluxation of MCP joint, Piano key styloid, Hitchhiker thumb deformity
• Irreversible deformities in Rheumatoid Arthritis

  • Boutonniere deformity, Swan neck deformity, Opera glass hand, Arthritis mutilans
• Other joints involved/deformities in Rheumatoid Arthritis


  • TM joint, C1-C2 joint (Odontoid process erosion), Cricoarytenoid (change in voice), 5th MTP, Pes planus, Forefoot varus, Ankle valgus
• Extra-articular manifestations of Rheumatoid Arthritis


  • Rheumatoid nodules, Neuro-ocular manifestations, Hematological manifestations, Lung manifestations, Cardiovascular manifestations, Renal manifestations, Gastrointestinal manifestations, Vasculitis
• Rheumatoid nodules


  • Most common extra-articular manifestation (40% cases), 20% develop within 1 yr of onset, Most common site: Olecranon, Non tender, Associated with smoking, Anti CCP/RF positivity, Early onset & long duration RA, Granulomatous reaction: Type 4 hypersensitivity, Size decreases on treatment
• Neuro-ocular manifestations in Rheumatoid Arthritis

  • CNS: No brain parenchymal involvement, C1-C2 myelopathy, Entrapment neuropathy
  • PNS: RA related small fibre peripheral neuropathy
  • Ocular: Dry eyes (Keratoconjunctivitis sicca), Episcleritis > scleritis, Thinning of sclera (scleromalacia perforans), Uveitis not a feature
• Hematological manifestations in Rheumatoid Arthritis

  • Anemia of chronic disease, Normal WBC count, Thrombocytosis, Rapidly progressive anemia (Warm IgG AIHA), Increased risk of diffuse large B cell lymphoma, LGL leukemia
• Felty syndrome


  RA + Neutropenia + Splenomegaly, Seen later in the disease, Nodules, deformities positive, RF positive, HLA-DRB1*04 positive, Antibody against citrullinated histones positive
• Lung manifestations in Rheumatoid Arthritis

  • Pleuritis (exudative effusion), ILD: Usual interstitial pneumonia (UIP) - Fibrosis, Traction bronchiectasis, Honeycombing, Loss of lung architecture, Cyst in the lung
  • Caplan syndrome: RA + nodules in lung + coal workers pneumoconiosis
• Cardiovascular manifestations in Rheumatoid Arthritis

  • Most common cause of death: MI (accelerated atherosclerosis), Most common presentation: Pericarditis without tamponade, Most common valvular disease: Mitral regurgitation
• Renal manifestations in Rheumatoid Arthritis


  • Most common manifestation: Secondary amyloidosis
• Gastrointestinal manifestations in Rheumatoid Arthritis

  • GI vasculitis
• Vasculitis in Rheumatoid Arthritis

  • Immune complex mediated small vessel vasculitis, Most common lesion: Purpura, Histology: Leucocytoclastic vasculitis, Dangerous forms: Medium vessel involvement (Gangrene), GI vasculitis, Mononeuritis multiplex
• Presentation of Rheumatoid Arthritis

  • Preclinical RA, Chronic symmetrical small joint polyarthritis (Most common), Palindromic rheumatism, Others: Flexor tendon tenosynovitis, Bursitis, Hypoandrogenism, Osteoporosis, Pyoderma gangrenosum
• Preclinical Rheumatoid Arthritis


  Genetic & environmental risk factors positive, Autoantibodies of RA positive, Symptoms without clinical evidence of RA
• Early morning stiffness of small joints + Normal examination & Xray findings

  Suspect Undifferentiated arthritis
• Symptoms <6 weeks


  Suspect post viral arthritis (Most common: Parvovirus)
• Symptoms persist >6 weeks

  Diagnosis of Rheumatoid Arthritis confirmed
• Outcomes of Undifferentiated Arthritis

  • Remission in 1/3rd cases, Evolve into RA in 1/3rd cases, Persists as UA or progress to other disease in 1/3rd cases
• Scoring factors determining undifferentiated arthritis evolving into RA

  • Age, Sex, Joint distribution, Morning stiffness, Tender & swollen joints, Markers: CRP, RF & anti CCP
  • Score >8: Treat as RA
• Management of Rheumatoid Arthritis

  1. Start DMARD: Methotrexate (5mg weekly dose may go upto 25 mg weekly dose), Monitor CBC, LFT

  2. Side effects: Mucositis, Dose dependent bone marrow suppression, Hypersensitivity pneumonitis, Decrease in size of nodules in 10% cases

  3. Remission assessment by Boolean