Acute Arthropathies“I’ve got a painful, swollen knee

doctor”

By Dr Mahya Mirfattahi GP ST1

HDR LRCH

9th December 2009

What could it be?

• Septic arthritis• Septic bursitis• Crystal arthropathies – gout, pseudogout• Acute exacerbation of osteoarthritis• Acute attack of rheumatoid arthritis• Trauma• Seronegative spondyloarthropathy• Viral infection• Lupus

Clinical assessment - History

• Patient demographics– Age, gender, ethnicity, obese

• History– Pain, swelling, stiffness, duration (short), site, preceding trauma,

other joints affected, previous episodes, systemic symptoms

• Past medical history– Joint prosthesis, osteoarthritis, previous trauma, inflammatory

arthritis, psoriasis, recent episodes of illness, diabetes mellitus, hypertension, recent corticosteroid joint injection, haemophilia

• Current medications– Bendroflumethiazide, aspirin, immunosuppressant therapy

Clinical assessment - Examination

• Look– Swelling, redness, scars, tophi, psoriatic plaques,

nails, nodules, joint deformities, ulcers

• Feel – Warmth, effusion, swellings

• Move– Restriction, crepitus, ability to weight bear, painful

movements

• Systemic features

Case 1

• 67 year old man

• Type 2 diabetic, suffers with ulcers on legs dressed by district nurse. LT catheter.

• Presents with acute history of painful, hot, swollen red knee

• Struggles to walk into surgery

• Feverish today

• Ulcers weeping

What would you like to do?

• History– Further enquiries reveal recent corticosteroid

injection in knee for OA symptoms

• Examination– Temp 37.8, tachycardic, red, hot, effusion,

unable to weight bear, restriction of movement

• Consider risk factors• What is the mandatory investigation?

Joint aspiration

Septic arthritis

• Overall mortality 10% in adults• Suppurative inflammation in joint space• Majority monoarticular• Large > small joints

– 50% knee, hip 20%, shoulder 8%, ankles 7%, elbow & IPJ 1-4%

• Most commonly haematogenous spread• Can be direct penetrating wound or neighbouring

infection• Children, neonates, elderly & immunosuppressed

Pathogens

• 90% non-gonococcal– staph aureus 50-80%, streptococcus 15-20%,

haemophilus influenzae b 20% (infants 6mo-2yrs), anaerobes 5%

• Gonococcal – young, sexually active– Pustular skin lesions (dermatitis-arthritis syndrome)– Tenosynovitis– Migratory arthralgias– Hand > knee, wrist, ankle, or elbow

Risk factors for septic arthritis

• Previously damaged joints • Prosthetic joints• Immunocompromised states• Systemic drugs – corticosteroids, DMARDS, biological

agents• IV drug abuse• Alcohol abuse• Diabetes• Previous intra-articular corticosteroid injection• Cutaneous ulcers• Indwelling catheters• >65 yrs old

Management

• If confident, joint aspirate to dryness & urgent gram stain

• Admit patient – discuss with orthopaedic on-call SHO

• Blood tests• Cultures – 3x blood, MSU, swabs• Plain XR• Start empirical antibiotics – 1st line flucloxacillin

IV 2g QDS• Discuss with microbiologist• Long duration of antibiotic therapy

Case 2

• 78 year old male

• Hypertensive, aspirin, osteoarthritis, renal impairment, obese

• Complains of painful, hot swollen knee

• Noticed swellings on hands

• Previous episode of joint pain in big toe 6mo ago settled with OTC NSAIDs

What will you do next?

• History– Further questioning reveals that had knee

arthroscopy last yr, likes alcohol

• Examination

• Investigations– Joint fluid aspirate, blood tests, plain XR

• What are his risk factors?

Risk factors for gout

• Low dose aspirin• Diuretic• Increasing age, male• Family history• Hypertension• Central obesity• Alcohol consumption• Renal insufficiency• Haematological disorders

Precipitants of attack

• Dehydration

• Injury

• Concurrent illness

• Dental extraction

• Excess foods/alcohol

Management

• Investigations– Joint aspiration –ve birefringent needle-shaped– Blood tests

• Rest joint• NSAID or if unable or not responding colchicine• Consider PPI• Caution use of colchicine in IHD,CCF• Give until pain relieved• Side effects – diarrhoea, abdominal cramps

Prevention• Review medications• Advise patients – diet, lifestyle, weight loss• Prophylaxis

– Indications: uncomplicated gout >2 attacks/yr, tophi, renal insufficiency, uric acid stones, need to continue diuretics

• Allopurinol– Start at 100mg od, gradually increase, monitor uric acid levels 4 weekly

until normal– Delay until 2/52 after intial attack settled– Monitor creatinine– SE: rash – stop & reintroduce lower dose– Interactions – Give colchicine/NSAID first 3-6mo – Continue allopurinol in attacks if pt already taking

• Referral to rheumatology if no improvement

Case 3

• 17 year old male

• Recent travel to Ibiza, playing football yesterday, bad tackle, able to continue game.

• Painful, swollen knee

• No past medical history

• Able to weight bear, but sore

• Differential?

What would you do next?

• History– Recent illness, STI, family history of bleeding

disorders

• Examination

• Investigations– Joint fluid aspirate, blood tests, plain XR

Haemarthrosis

• Plain XR – fat/blood interface

• Common cause– Ligament injury (cruciates in sports)– Intra-articular #

• Inherited haemophilias – APTT, assays for factors VIII, IX

Lipohaemarthrosis

Case 4 – a real story!

• 52 year old lady

• Presents with confusion

• Osteoarthritis, TKR 6 wks ago, obese

• Fever, ache in knee, coughing

• Husband very concerned requests GP home visit

Assessment

• Confused to time, place & person• Smelly urine• Coughing, complains of back pain,

breathless• Temp 38.6, tachycardic, consolidation

lower lobe, urine dip positive• Knee – scar clean, dry, healed well. No

effusion. Not red. Slight warmth. Tender ROM, but no restriction.

What will you do next?

• Admit to AMU

• Orthopaedic review?– Yes, needs assessment

• Investigations– Blood tests– Cultures – 3x blood, MSU– CXR– Plain XR Knee

Management

• Needs joint aspiration in theatre, washout of knee

• May need removal of prosthesis

• Empirical antibiotics intravenous long term

• Discuss with microbiologist

• Monitor inflammatory markers

Pseudogout

• Consider when intermittent attacks• Monoarticular – knee, wrist, hip• Can simulate bacterial infection – severe inflammation & fever• Can be symmetrical• Joint damage can be severe• Investigations

– Joint aspiration = calcium pyrophosphate dehydrate crystals (CPPD), rhomboid shaped, +ve birefringent

– Plain XR – chondrocalcinosis– Causes – must screen for hyperparathyroidism,

haemachromatosis, hyphosphataemia, hypomagnesiaemia

• Treatment – Rest, ice, NSAIDs, colchicine, intra-articular steroid injection

Reactive arthritis

• Aseptic arthritis• Occurs 2-6wks after bacterial infection elsewhere

– Gastroenteritis (salmonella, campylobacter)– GU infection (chlamydia, gonorrhoea)

• Can be HLA B27 +ve• Treatment – NSAIDs, physiotherapy, steroid joint

injections• Reiter’s syndrome

– Polyarthropathy, urethritis, irits, psoriaform rash– Follows GU/GI infection– Joint & eye changes often severe

Diagnosis?

What are these?

Diagnosis?

Diagnosis?

Useful Resources

• GP notebook

• Doctors.net e-module on acute swollen joint

• ARC (www.arc.org.uk)

• Patient uk

• www.ukgoutsociety.org

• www.arthritiscare.org.uk