#112 Gout Flares: Bathtubs and Firefighting

September 3, 2018 | By Matthew Watto, MD

Crystalize your knowledge of gout and stop flares in their tracks with tips from expert, Tuhina Neogi MD, PhD, Professor of Medicine at Boston University School of Medicine. On this first of two gout episodes we learn to diagnose gout with or without arthrocentesis, how to treat flares, and how to counsel patients about gout, which apparently involves fire fighting and bathtubs. Don’t miss next week’s episode on urate lowering therapy, gout guidelines controversy, and answers to your gout questions from social media.

Credits:

• Written and produced by: Matthew Watto MD
• Hosts: Paul Williams MD, Stuart Brigham MD, Matthew Watto MD
• Guest: Tuhina Neogi MD, PhD

Clinical Pearls

1. Diagnosis of gout: Pain peaks within 24 hours. Erythema should be localized to a joint (Not extending far beyond! If so, then think cellulitis) with “peripheral sensitization” (e.g. can’t tolerate touch of bed sheet). Ask yourself: Was there trauma and could this be a fracture? Is arthrocentesis needed to exclude septic arthritis?
2. Arthrocentesis is the gold standard for diagnosis, but often not feasible. Clinical classification criteria are NOT meant for diagnosis, but can augment clinical evaluation for gout. -Dr Neogi
3. Natural history: Pain peaks in 24 hours and lasts up to 14 days, but untreated gout can progress to a chronic inflammatory arthritis.
4. Don’t focus on dietary habits. This leads to patient “blaming and shaming”. -Dr Neogi
5. Flare management: Do not stop treatment before 10 days. Otherwise, the patient may have rebound symptoms. Dr Neogi uses prednisone 30 mg po daily and tapers by 5 mg every 2 days (12 days total).

In-depth Show Notes

Background

Gout is caused by an elevation of uric acid in the blood combined with genetic factors and patient comorbidities. Hyperuricemia is present in over 20% of the population, but only about four percent of the population has gout (Zhu Arthritis Rheumatism 2011). Two-thirds of urate is excreted by the kidneys and one third via the GI tract. Chronic kidney disease promotes urate underexcretion and predisposes patients to gout (Sidari Prim Care Clin Office Pract 2018).

Sites

The first metatarsal phalangeal joint (1st MTP) is most commonly affected. Other commonly affected joints include: insteps of the feet, heels, ankles, and knees. Less common sites include the wrists, elbows, and even small joints of the fingers (Sidari Prim Care Clin Office Pract 2018).

Firefighting

Gout flares can be explained to patients as a joint being “on fire” as the body develops an inflammatory response to the monosodium urate (MSU) crystals in the joint. Steroids, NSAIDS, or colchicine can be used to put out the fire.

Bathtubs

Dr Neogi’s bathtub analogy explains gout as a process whereby the bathtub (i.e. the body and joints) becomes overflowed with water (i.e. urate and uric acid). When the water level gets to high, it spills over and causes an electrical short/fire (i.e. gout flare). To treat gout we can:  

1. Turn off the faucet with urate lowering therapy e.g. allopurinol, febuxostat
2. Dump out the water with a bucket e.g. use pegloticase (uricase) to metabolize uric acid
3. Drain the bathtub using uricosuric agents e.g. probenecid.

Diagnosis

In practice a clinical diagnosis is most common. Arthrocentesis remains the gold standard for diagnosis, and while a crystal proven diagnosis is uncommon due to logistics, it should be pursued if possible. MSU crystals are needle-shaped, and yellow if parallel, but blue if perpendicular to the light polarizer. MSU crystals can even be found in the joints between flares!

Classification criteria

Classification criteria are used to enroll a homogenous population for clinical trials. These should not be substituted for a clinician’s diagnostic reasoning, but can be helpful in identifying the key features of gout when considering this diagnosis (Calculator http://goutclassificationcalculator.auckland.ac.nz). –Dr Neogi

Flare management

The 2016 EULAR gout guidelines recommend a pill-in-pocket strategy for “fully informed” patients to promote prompt self management of gout flares (Richette Ann Rheum Dis. 2017). Dr Neogi notes that evidence suggests that patients are better at managing their own flares.

Colchicine

Colchicine is less effective if started after 24 hours into a flare. Give 1.2 mg at first sign of flare followed in one hour by another 0.6 mg (Lexicomp). Continue colchicine at 0.6 mg twice daily until the flare resolves, usually up to 14 days (Dr Neogi’s expert opinion). Be careful with concomitant use of CYP3A4 inhibitors like diltiazem.

Glucocorticoids

Start at 30 mg prednisone daily and decrease the dose by 5 mg every two days (12 day course). Higher dose may be used for polyarticular gout. –Dr Neogi’s expert opinion.

NSAIDS

Start ibuprofen 800 mg three times daily for 3 days, then give 400 mg three times daily for the remaining 7-10 days (Dr Neogi’s expert opinion). No specific NSAID is recommended over others (Sidari Prim Care Clin Office Pract 2018).

Goal: Listeners will develop a both a practical and evidence based approach to the diagnosis and management of gout flares.

Learning objectives:

After listening to this episode listeners will…

1. Review the pathophysiology of gout
2. List common risk factors for gout
3. Develop a spiel to counsel patients about gout
4. Initiate pharmacologic therapy for gout flares

Disclosures: Dr Neogi reports no relevant financial disclosures. The Curbsiders report not relevant financial disclosures.

Time Stamps

• 00:00 Disclaimer, intro
• 01:40 Guest bio
• 03:20 Guest one liner, music recommendations, advice for researchers, and some comments on failure
• 09:15 Clinical diagnosis of gout
• 12:15 Is taking a diet history useful?
• 14:30 Classification criteria for gout
• 17:35 MSK ultrasound and Physical exam findings in gout
• 21:06 Arthrocentesis and MSU crystals
• 24:45 A recap of how to make the diagnosis of gout
• 26:50 The bathtub analogy and how to counsel a patient with a new diagnosis of gout
• 30:55 Pathophysiology of gout
• 34:55 Treatment for acute gout flares (steroids, colchicine, NSAIDS. And topical NSAIDS?)
• 45:30 Outro

Links from the show:

1. Dr Sidari and Dr Hill on the treatment of gout and pseudogout in everyday practice (institutional access required) https://www.ncbi.nlm.nih.gov/pubmed/29759121
2. ACP 2017 Clinical Practice Guideline on Gout http://annals.org/aim/fullarticle/2578528/management-acute-recurrent-gout-clinical-practice-guideline-from-american-college ; Accompanying editorial by RM McLean MD http://annals.org/aim/fullarticle/2578454/long-winding-road-clinical-guidelines-diagnosis-management-gout
3. American College of Rheumatology 2012 Guidelines Part 1 2012 American College of Rheumatology Guidelines for Management of Gout Part 1: Systematic Nonpharmacologic and Pharmacologic Therapeutic Approaches to Hyperuricemia
4. American College of Rheumatology 2012 Guidelines Part 2 2012 American College of Rheumatology Guidelines for Management of Gout Part 2: Therapy and Antiinflammatory Prophylaxis of Acute Gouty Arthritis
5. Web based calculator to assess likelihood of gout based on ACR-EULAR criteria http://goutclassificationcalculator.auckland.ac.nz