Crystal Arthritis

Dr. C. C. Visser

Crystal Arthritis

• Gout (monosodium urate)

• Pseudogout/Chondrocalcinosis (CPPD)

• Apatite deposition disease

GOUT

Clinical Picture

• Acute attacks of gout• Chronic gout with/without tophi• Kidney stones• Renal failure

Acute goutThere is redness of the skin of the dorsum of the foot with marked swelling of the entire foot and ankle.

Tophaceous goutTophi involving the first, second and fifthmetatarsophalangeal joints with little involvement of overlying skin.

Tophaceous goutAn ulcerating tophus of a distal interphalangeal joint with associated redness of the overlying skin

Tophaceous goutExtensive tophi of all digits

Tophaceous goutAuricular tophi.

Tophaceous GoutThe appearance of tophi at arthroscopy.

Tophaceous GoutGouty microtophi. Multiple small tophi over the head of a firstmetatarsophalangeal joint in a patient who had suffered multiple attacks of acute gout.

Diagnosis

• Urate level

• Radiology

• Synovial fluid: MSU crystals

• Histology: MSU crystals

Serum Urate

• Higher in males than in females

• Falsely low during an acute attack

• Range: 0,21-0,42 mmol/l

• Aim: reduce level to < 0,3 mmol/l

A large tophus is replacing much of the fifth left metatarsal.

• Soft tissue densities due totophi.

• Classical ‘punched-out’para-articular erosion with a sclerotic margin of the proximal phalanx.

Synovial fluid

Gold standard in diagnosis

Polarized light microscopy of urate crystals. Illustrated are extracellularbirefringent needle-shaped urate crystals.

Polarized light microscopy of urate crystals. Illustrated are intracellularbirefringent needle-shaped urate crystals.

Polarized light microscopy. Schematic representation of the effect of the orientation of aurate crystal with respect to the direction of the plane of slow vibration of light when using a red-plate compensator (retardation plate).

Histology

• Send sample in 100% alcohol

Synovial gouty tophus.Synovium from a patient with gout where the uratecrystals from themicrotophus have been dissolved by formalin.

Polarized light microscopy of a gouty tophus. There is a mass of urate crystals from a gouty tophus.

Management

PSEUDOGOUT/CHONDROCALCINOSIS

Clinical presentation

• Acute attacks (pseudogout)• Chronic arthritis• Calcification of cartilage/soft tissues

Pseudogout affecting the knee. Seen here in an elderly lady with background chronic pyrophosphatearthropathy. Blood-staining of synovial fluid is common in this situation.

Characteristic elderly female patient with marked knee, wrist, andmetacarpophalangealpyrophosphatearthropathy.

‘Bloody old shoulders’. This elderly patient has visible swellings of both shoulders.

‘Bloody old shoulders’. This elderly patient has visible swellings of both shoulders. Aspiration revealed a large amount of blood-stained fluid which contained numerous particles of basic calcium phosphates.

Diagnosis

• Synovial fluid: CPPD crystals

• Radiology: calcification

Synovial fluid CPPD crystals.

Subacromial bursitis with large effusion

Knee radiograph showingchondrocalcinosis of bothfibrocartilage (meniscus) and hyaline cartilage.

Knee radiograph showinghypertrophic OA features. Note prominant patello-femoral involvement, typical of pyrophosphate arthropathy.

Hand radiograph showing typical radiocarpalinvolvement. Noteprominant cyst formation, and CC.

Calcification affectingmetacarpophalangealjoints.

Achilles tendon calcification.

Anteroposteriorradiograph of the shoulder joint showing a largecalcific deposit in thesupraspinatus tendon. The deposit is dense, homogenous and well-defined, findings characteristic of inertcalcific periarthritis.

Anteroposteriorradiograph of the shoulder joint showing a smallperiarticular calcificdeposit. Other views may be needed to identify small deposits and the site of deposition.

Treatment

• Aspirate joints• Symptomatic relief• Consider colchicine prophylaxis if recurrent

acute attacks

APATITE DEPOSITION

• Anteroposteriorradiographs of a shoulder joint affected by apatite-associated destructive arthritis (‘Milwaukee shoulder’). The extensive destruction of soft tissues, including the rotator cuff, has led to instability of the shoulder. Note the extensive atrophic destruction and loss of bone of both theacromium and theglenohumeral joint.

Alizarin red S stain of anapatite particle isolated from the synovial fluid of a patient withosteoarthritis.

High magnification transmission electron micrographs of apatitecrystals. The crystal lattice structure as well as the morphology of the crystals is apparent.

Bones from a patient with advanced apatiteassociated destructive arthritis. The humerusshows the extent of the attrition and loss of bone that can occur in this condition. The tibial condyles show the characteristic destruction of the lateral tibiofemoraljoint, with extensive loss of subchondral bone.