What is a very general DDx for monoarticular joint pain (ie, pain in the first MTP)?
trauma, infection/sepsis, crystalline disease (gout, pseudogout), Rheumatoid Arthritis, cellulitis
what symptoms suggest gout?
-sudden episodes of severe joint pain, redness, swelling
-usually reaches peak in 12-24 hrs, self-resolves in 10-14 days
-may awaken patients from sleep
-may be tophi (non-tender)
what are risk factors for gout?
-family history of kidney stones
-excessive alcohol use
-meds that increase serum urate (diuretics)
what is podagra?
acute inflammation of the first MTP with swelling, erythema, pain (regardless of cause). characteristic of gout (Greek: seizure of the foot)
what is the difference in etiology between gout and pseudogout?
-gout = needle-like crystals, monosodium urate
-pseudogout = rhomboid crystals, calcium pyrophosphate
what are some clinical signs of pseudogout?
-sudden attacks of joint pain, swelling, warmth
-may have fever due to inflammatory reaction
-knee is often affected
what clinical features distinguish gout from RA?
Timing: RA is usually more of a chronic onset.
Distribution: some RA patients present with monoarticular dz, but usually RA is poly-articular and bilateral. hands are usually involved with RA.
Pain: RA is worst in morning, improves with usage.
Systemic sx: RA accompanied by fatigue, low fever, malaise
what clinical features distinguish gout from Psoriatic Arth?
Distribution: PA may be more axial, polyarticular
Joint features: PA may present with podagra or dactylitis (sausage digit). usually PA is less painful
Systemic sx: PA usually has enthesopathy, psoriasis, nail changes or eye inflammation.
what clinical features distinguish gout from Osteo Arth?
Timing: Gout is acute, OA is chronic
OA is non-inflammatory
Pain: OA won't wake you up at night
Distribution: OA commonly affects the 1st MTP joint, wrists, hips, knees --> bony prominences
OA may have joint deformation, crepitus
what tests should be ordered to evaluate gout?
-aspiration of the joint fluid. culture, crystals
-CBC with diff: WBCs, liver/renal function
-uric acid (tho may be low during attack)
-blood cultures to r/o septic arthritis
-joint xray (trauma)
if you only had one test you could run on a possible gout patient, what would it be?
culture/gram stain joint fluid for sepsis because septic arthritis is an emergency
what is the difference between gout crystals and CPPD (pseudogout) crystals?
-gout: needle shaped, monosodium urate crystals. BRIGHT. yellow along plane of (parallel to) polarized light. blue when perpendicular to the axis of light. very "negatively birefringent"
-pseudogout: rhomboid shaped, dull. BLUE when parallel to polarized light, yellow when perpendicular. "positively birefringent"
(Pic this side is CPPD; other side is gout)
describe xray findings in gout
'punched out' erosions at joint margins, sclerosis. not seen until 5 yrs post first attack in untreated patients. soft tissue swelling during acute attack
what can contribute to hyperuricemia?
obesity (associated), low dose aspirin, HCTZ (causing under-excr of uric acid), EtOH use (both underexcretion and overproduction) Fructose consumption causes direct elev.
treatment for acute gout?
-NSAIDs in max doses
-oral colchicine (if started within 12 h). give hourly until relief or GI side effects (diarrhea)
-IM steroids (prednisone)
Treatment to lower serum uric acid (long-term treatment of gout)?
-allopurinol, febuxostat (xanthine oxidase inhibitors)
-colchicine (for first few months of allopurinol tx)
dietary treatment of gout?
-avoid beer, liquor.
-avoid fructose, fruit juice, soda.
-avoid meat, fish, seafood
-low fat dairy is good (helps excretion of uric acid)
generally for long-term treatment of gout, we like to have serum uric acid under what level?
under 6 mg/dL
patients with asymptomatic hyperuricemia: should they be treated?
controversial: >75% of these pts will not develop clinical consequences (such as gout, kidney stones). unclear that daily meds would be beneficial
describe a typical presentation of fibromyalgia
-chronic, widespread pain not explained by another disorder
-some swelling, stiffness
-no swelling, infection
-pain above and below waist, BIL and axial
-at least 3 months
-pain may awaken from sleep
-somatic complaints: fatigue, sleep/mood/cog disorders
what is the role of blood tests in fibromyalgia?
if anything is abnl, suggests another disease process.
DDx for fibromyalgia?
-inflammatory arthritis (would have synovitis, decr ROM)
-osteoarthritis (might have limited spine ROM)
-spondyloarthropathy (would have limited spine ROM)
-myositis (would have more weakness)
other diagnoses that are part of the Fibromyalgia Spectrum?
CFS, restless leg, IBS, irritable bladder, chemical sensitivities, primary dysmennorrhea, migraines, periodic limb movement during sleep, tension headaches, TMJ, myofascial pain sx
what is the tenderpoint exam?
To dx fibromyalgia, pts need to have pain in 11/18 areas (tenderpoints).
This exam has been dropped from the official disease criteria, but still used
what 3 lab studies should I definitely order for fibromyalgia?
CBC (does pt have anemia?)
ESR (does pt have inflammatory disorder?)
TSH (does pt have hypothyroid?)
pathogenesis of fibromyalgia?
-theoretical only: underlying CNS disorder leading to increased sense of pain --> different perception of heat, pressure, electrical current. also, decr ability to dampen noxious stimuli.
-another theory = affective/somatiform disorder
elements of a fibromyalgia treatment plan?
-low impact exercise
-meds to help sleep, relieve pain
-cognitive behavioral therapy (coping with pain)