Transcript Clinical Slide Set. Gout - Annals of Internal Medicine

In the Clinic
Gout
© Copyright Annals of Internal Medicine, 2016
Ann Int Med. 165 (1): ITC1-1.
What are the risk factors for gout?
 Hyperuricemia
 Male sex
 Older age
 Obesity
 Diet high in animal sources of purines (red meat, shellfish)
 Alcohol and high-fructose corn syrup-sweetened drinks
 Medications (thiazide or loop diuretics, cyclosporine)
 Renal insufficiency
 Organ transplantation
 Genetic risk factors
© Copyright Annals of Internal Medicine, 2016
Ann Int Med. 165 (1): ITC1-1.
What comorbid diseases are associated
with gout?
 Renal insufficiency
 Psoriasis
 Hypertension
 Diabetes
 Hyperlipidemia
 Metabolic syndrome
 Cardiovascular disease
© Copyright Annals of Internal Medicine, 2016
Ann Int Med. 165 (1): ITC1-1.
Are there effective strategies for
prevention?
 Dietary changes and weight loss
 May lower serum urate levels
 Therapy not indicated for asymptomatic hyperuricemia
 Not proven to have adverse consequences
 Long-term ULT may carry long-term risks
 Treatment guidelines may change if there are sufficient
evidence to show that hyperuricemia confers increased
renal or cardiovascular disease risk
© Copyright Annals of Internal Medicine, 2016
Ann Int Med. 165 (1): ITC1-1.
CLINICAL BOTTOM LINE: Prevention
and Screening...
 Risk factors
 Hyperuricemia
 Age, sex, obesity, renal insufficiency, diuretic use, diet
 Genetic variants may increase risk
 Common comorbidities
 Diabetes, CVD, renal impairment, hypertension, metabolic
syndrome, hyperlipidemia
 Therapy not recommended for asymptomatic hyperuricemia
 Lifestyle modifications appropriate in patients with only 1
gout attack and no other indications for ULT
© Copyright Annals of Internal Medicine, 2016
Ann Int Med. 165 (1): ITC1-1.
What symptoms and physical examination
findings suggest gout?
 Acute onset joint pain at night
 Swollen, erythematous, warm, exquisitely painful joint
 Maximum pain within 24 h and resolves within 2 weeks
 First Metatarsophalangeal joint most commonly involved
 MSU crystals tend to form in previously diseased joints
 With longer-disease duration and unabated
hyperuricemia, persistent inflammation may occur
 Urate deposition may be evident as subcutaneous nodules
 Imaging may reveal tophaceous deposits
© Copyright Annals of Internal Medicine, 2016
Ann Int Med. 165 (1): ITC1-1.
What tests can diagnose gout?
 Examination of synovial fluid or tophus aspirate
 Polarized microscopy, cell count, culture
 MSU crystals in synovial fluid or tophus aspiration
required to establish diagnosis
 Other useful tests in diagnosing gout
 Serum urate level
 CBC with differential (if considering septic arthritis)
 Radiography (to rule out other causes or to look for gouty
erosions when symptoms are long-standing)
 US or DECT imaging (to identify findings specific for gout)
© Copyright Annals of Internal Medicine, 2016
Ann Int Med. 165 (1): ITC1-1.
What is the value of imaging?
 Plain radiography
 Show gout-related bone erosion, tophi
 Show conditions coexisting with or confused for gout
 Ultrasonography
 Facilitate joint aspiration
 Identify articular urate deposition, tophi, inflammation
 DECT (not yet used in practice)
 Differentiate calcium from urate
 MRI (not routinely used in practice)
 Show joint inflammation, damage, tophi—but cannot
necessarily distinguish gout from CPP arthritis
© Copyright Annals of Internal Medicine, 2016
Ann Int Med. 165 (1): ITC1-1.
What are the differential diagnoses?
 Calcium pyrophosphate deposition
 Septic arthritis
 Cellulitis
 Rheumatoid arthritis
 Osteoarthritis
 Psoriatic arthritis
 Sarcoidosis
© Copyright Annals of Internal Medicine, 2016
Ann Int Med. 165 (1): ITC1-1.
What classification criteria are used for
gout in research studies?
 MSU in synovial fluid or tophus aspiration is sufficient
for classification as gout
 ACR/EULAR criteria encompass following parameters:
 Pattern of joint involvement during symptomatic episodes
 Characteristics of symptomatic episodes
 Time course of symptomatic episodes
 Clinical evidence of tophus
 Highest level of serum urate ever recorded off-treatment
 MSU results of synovial fluid analysis
 Imaging evidence of urate deposition
 Imaging evidence of gout-related joint damage
© Copyright Annals of Internal Medicine, 2016
Ann Int Med. 165 (1): ITC1-1.
CLINICAL BOTTOM LINE: Diagnosis...
 MSU crystals in synovial fluid or tophus confirm diagnosis
 Joint pain and hyperuricemia alone do not
 Aspirate synovial fluid from joint or suspected tophus
 Serum urate measurement is helpful but not diagnostic
 Examine aspirated material under polarizing microscopy to
differentiate gout from CPP-related arthritis
 Examine synovial fluid cultures and clinical features to
differentiate from septic arthritis
 Radiography and ultrasonography: help identify other joint
conditions and gout-specific features
© Copyright Annals of Internal Medicine, 2016
Ann Int Med. 165 (1): ITC1-1.
When should clinicians consider
hospitalizing a patient with gout?
 Gout attacks are one of the most painful conditions
 Hospitalization is warranted if:
 Patient cannot care for self at home
 Septic arthritis is a concern (to diagnose definitively and
administer antibiotics promptly to prevent joint damage)
 To monitor response to therapy, repeated synovial fluid
analysis may be warranted for cell count and culture
© Copyright Annals of Internal Medicine, 2016
Ann Int Med. 165 (1): ITC1-1.
What is the role of nonpharmacologic
therapy in managing patients who already
have gout?
 Adjunct to long-term pharmacologic management
 Most patients with gout require pharmacologic therapy
 Lifestyle changes may help reduce serum urate levels
 Reduce consumption of dietary contributors
 Weight loss
 Adequate hydration
 Don’t blame patients for gout
 Renal urate underexcretion, with genetic underpinnings, is
the major contributor
© Copyright Annals of Internal Medicine, 2016
Ann Int Med. 165 (1): ITC1-1.
What is the role of pharmacologic therapy?
 Most patients require pharmacologic therapy
 Urate-lowering therapy: cornerstone of management
 Prophylaxis: when starting ULT to mitigate expected
increased risk for attacks during initial phase
 Anti-inflammatory therapy: for gout attacks
 Indications for urate-lowering therapy
 Frequent attacks (≥2 per year)
 Tophus on clinical examination or imaging study
 Chronic kidney disease stage ≥2
 Past urolithiasis (of any type)
© Copyright Annals of Internal Medicine, 2016
Ann Int Med. 165 (1): ITC1-1.
When should clinicians consider
consulting a specialist?
 If a septic joint is suspected
 To aid with joint aspiration
 When gout is difficult to manage
 First-line monotherapy insufficient
 Contraindication or caution for gout attack management
 Features may be related to other forms of arthritis
 Patient is young, with possible inherited metabolic disease
 Surgery is not indicated except when tophi pose an
urgent function- or organ-threatening risk
© Copyright Annals of Internal Medicine, 2016
Ann Int Med. 165 (1): ITC1-1.
CLINICAL BOTTOM LINE: Treatment...
 Pharamcologic treatment
 ULT if the patient has a clinical indication
 Prophylaxis when initiating ULT
 Anti-inflammatory therapy for gout attacks
 Patient education
 Causes of gout
 Management of hyperuricemia
 Adjunctive lifestyle modifications
 Hospitalization warranted when gout-related pain and
functional limitations cannot be controlled
© Copyright Annals of Internal Medicine, 2016
Ann Int Med. 165 (1): ITC1-1.