Approach to Arthritis
General Overview
Arthritis
Duration?
Acute Chronic
Infection Inflammation?
Trauma/hemarthrosis
Crystal deposition Yes No
Reactive
Early chronic
Number of joints involved? Osteoarthritis
Mono Oligo Poly
Indolent infection Indolent infection RA
Early oligo/poly Seronegative SLE
Early poly Scleroderma
Polymyositits
Dermatomyositis
Arthrocentesis – Analysis of Joint Fluid
Normal Noninflammatory Inflammatory Septic
Appearance clear clear, yellow Clear-opaque, yellow-white Opaque
WBC/mm3 <200 <2000 >2000 >2000 but usually >100,000
Neutrophils <25% <25% ≥50% ≥75%
Culture negative negative Negative Positive
Glucose ≈serum ≈serum 25<glu<serum glu <25
Conditions OA, trauma RA, crystal, CTD, seroneg Infection
Case 1
36 year old male with history of IV drug abuse presents with fever and right knee pain for 1 day. He states the pain is sharp and has increased in severity to the point where he is having difficulty walking. He has noticed that his knee is also swollen. He has no other joint complaints. On physical exam, T 38.4 HR 95 BP 120/80 RR 14 O2Sat 100% room air. His cardiac exam is notable for a 2/6 systolic murmur at the left lower sternal border. His right knee has a palpable effusion with a ballotable patella. His right knee is tender to palpation, erythematous and warm to the touch. Range of motion is approximately 50% and tender.
1. What are important aspects of the knee exam?
-inspection – look for erythema, asymmetry, swelling
-palpation – assess for tenderness, warmth, range of motion, effusion, and joint line tenderness
2. What is your differential diagnosis?
-septic arthritis, gout, gonococcal arthritis, reactive arthritis, trauma
3. What would you do next?
-FBP, ESR, blood cultures
-arthrocentesis – cell count, differential, culture, glucose, crystals
4. What is the typical presentation for septic arthritis?
-acute monoarticular arthritis, fever/chills, severe pain
-remember dolor, calor, rubor, tumor
-knee is the most common joint involved however can also commonly involve hip, wrist, shoulder, ankle
-oftenly occurs in the setting of immunosuppression (diabetes, IDS, elderly), bacteremia (ie endocarditis), damaged joints (rheumatoid arthritis, osteoarthritis, gout, trauma, prosthetic joints)
5. What are the most common organisms?
-Gram positive cocci: Staph aureas, Staph epidermidis, Strep
-Gram negative rods: E. coli, Pseudomonas, Serratia
-Neisseria gonorrhoeae: commonly presents with fever, chills, rash and migratory arthritis, cultures of joint fluid are usually negative
-remember that other organisms can cause septic arthritis including syphilis, mycobacteria, fungus
-viral infections can lead to arthritis as well (parvovirus B19, Hepatitis B,
Hepatitis C, rubella, HIV)
6. What is the most likely underlying etiology in this patient?
-bactermia and possible endocarditis secondary to IV drug abuse
7. What is the treatment?
-antibiotics
-joint washout – either accomplished through serial arthrocentesis or open surgical procedure
Case 2
36 year old female with no past medical history presents with wrist and hand joint pain for 6 weeks. She complains of pain and swelling of both of her wrists and both hands. Denies fever. Also states that she has joint stiffness in the morning which improves as the day goes on. On physical exam, T37.2 HR 75 BP 120/80 RR 12 O2Sat 99% room air. Her hand exam is notable for bilateral wrist tenderness and swelling in addition to bilateral MTP joints. No hand deformities. Her range of motion is approximately 75%.
1. What is your differential diagnosis?
-rheumatoid arthritis, SLE, reactive arthritis
2. What would you like to do next?
-ask further questions about her history (for example family history, rheumatologic review of systems)
-check FBP, ESR, RF, ANA, hand x-ray (in the US you can also check CRP and anti- cyclic citrillinated peptides)
3. What are the classification criteria for rheumatoid arthritis?
-need 4 of 7 of the following: morning stiffness ≥ 1 hour, arthritis ≥ 3 joints simultaneously, hand joint arthritis, symmetric joint involvement, rheumatoid nodules, positive rheumatoid factor, radiographic changes consistent with RA (ie erosions and periarticular decalcification)
4. Do you need to perform an arthrocentesis?
-not necessarily, however can be performed if there is enough synovial fluid and if the diagnosis is unclear
5. What are the clinical manifestations of rheumatoid arthritis?
-synovitis of joints (most common PIP, MCP, wrist, knee, ankles, MTP, c-spine), morning stiffness, bone destruction, joint deformities, C1-C2 instability, rheumatoid nodules, ocular (sicca, scleritis), pulmonary (interstitial lung disease, pleural disease), cardiac (pericarditis, pericardial effusion, aortitis), heme (anemia of chronic disease, leukemia, lymphoma)
-long standing RA can lead to vasculitis, secondary amyloidosis and Felty’s syndrome (active RA, splenomegaly, neutropenia)
6. What is the treatment for rheumatoid arthritis?
-NSAIDs (in the US also use COX-2 inhibitors)
-glucocorticoids
-DMARDs
-at Bugando methotrexate, azathioprine and cyclosporine are available
-other agents include hydroxychloroquine, sulfasalazine, penacillamine, gold, minocycline, gold
-newer agents available in US include leflunomide, anti-TNF agents (enteracept, infliximab, adalimumab), anakinra (IL-1 inhibitor)
7. Other rheumatological diseases can present with inflammatory arthritis as part of the systemic disease including SLE, scleroderma, polymyositis, dermatomyositis
Case 3
61 year old male with history of hypertension presents with pain and swelling in his right great toe for 1 day. He states that the pain is so severe that he cannot walk or tolerate anything touching his foot. He denies fever. This is the first episode of this nature. Of note, he was started on a thiazide diuretic 2 weeks ago for his hypertension. On physical exam, T 37.3 HR 90 BP 145/70 RR 12 O2Sat 99% room air. The MTP of his right great toe is swollen, erythematous, warm and tender. His range of motion is limited.
1. What is the differential diagnosis?
-gout, psuedogout, septic arthritis, trauma
2. What would you like to do next?
-check FBP, ESR, uric acid
-check foot x-ray to exclude chondrocalcinosis or septic changes
-arthrocentesis – check cell count, gram stain, culture, crystals
-to make the diagnosis of gout use polarized microscopy to look for crystals: needle-shaped negatively birefringent crystals indicate gout
-joint fluid with WBC 20,000-100,000, neutrophils >50% consistent with gout
3. What are the clinical manifestations of gout?
-acute arthritis – monoarticular, MTP of great toe is very common (“podagra”)
-more common in men
-precipitants: diet high in purines or alcohol, surgery, infection, diuretics, dehydration
-other findings: tophi, bursitis, chronic arthritis, uric acid stones, gouty nephritis
4. What is the etiology?
-overproduction of uric acid: inherited defect, excessive purine ingestion, excessive alcohol ingestion, myeloproliferative disorder, cytotoxic drugs
-underexcretion of uric acid: inherited, dehydration, drugs (diuretics, pyrazinamide, ethambutol, salicylates, cyclosporine), keto- or lactic acidosis
5. What is the treatment?
-NSAIDs
-colchicine (not on formulary in Tanzania)
-corticosteroids (make sure there is no joint infection prior to treating)
6. What is the chronic treatment for gout?
-modify diet – decrease consumption of high purine foods (meat, spinach, beans) and alcohol
-avoid dehydration and diuretics
-for overproducers, use allopurinol (xanthine oxidase inhibitor)
-for underexcreters, use probenecid (not available in Tanzania)
The other major crystal arthropathy is calcium pyrophosphate dehydrate deposition disease (CPPD).
-acute monoarticular arthritis, more common in the elderly
-most cases have idiopathic etiology, in general secondary to increased levels of pyrophoshates produced by the chondrocytes
-arthrocentesis reveals rhomboid weakly positive birefringent crystals
-x-rays commonly show punctuate and linear densities in articular hyaline
-if diagnosis is made, screen for metabolic disease by checking calcium, magnesium, TSH, iron, glucose, urinalysis
-treatment is similar to gout
Case 4
65 year old female with history of hypertension and hyperlipidemia presents with bilateral knee pain for 3 months. She describes the pain as dull and achy. It gets worse over the course of the day, especially if she walks a lot. She denies morning stiffness and fever, but states she her knees feel stiff is she is sitting for a prolonged period of time. On physical exam, T 37.0 HR 75 BP 135/80 RR 12 O2Sat 100% room air. Her knee exam shows no effusions, no erythema, no warmth, positive creptitus, no joint line tenderness, and full range of motion.
1. What is your differential diagnosis?
-osteoarthritis, pseudogout, tendonitis
2. What would you like to do next?
-knee x-ray - this shows joint space narrowing, osteophytes and no soft tissue swelling
3. Is it necessary to obtain any laboratory tests?
-Osteoarthritis is a clinical diagnosis. No laboratory examinations are needed.
-FBP, serum chemistries and ESR should be normal. Arthrocentesis can be performed if you are unsure. It should yield clear or yellow fluid, mild leukocytosis (WBC <2000), neutrophils <25%, negative gram stain and culture.
4. What is the clinical presentation of osteoarthritis?
-occurs more often in the elderly
-chronic mono- or polyarticular arthritis
-typically involves knees, hips, spine and DIP joints
-risk factors include age, female sex, major joint trauma, repetitive stress (ie vocational), obesity, congenital/developmental defects, prior inflammatory joint disease)
-pain usually aggravated by use and relieved by rest, stiffness can occur with prolonged period of inactivity
-physical exam can demonstrate localized tenderness, bony or soft tissue swelling, bony crepitus, possible small effusions, periarticular muscle atrophy, heberden’s nodes
5. What is the treatment?
-nonpharmacologic: reduction of joint loading (ie weight loss, decreased repetitive movement), exercise, patient education
-pharmacologic: pain relief with NSAIDs, acetaminophen, opiates, (in the US also use selective COX-2 inhibitors, glucocorticoid injections, hyaluronan injections)
Case 5
32 year old male with no significant past medical history presents with complaints of knee and ankle joint pain for 3 days. He states that he has a recent diarrheal illness about 10 days ago. He describes the pain as dull and severe. He has also noticed that he has urethral discharge and red eyes. He denies fever. On physical exam, T 36.9 HR 80 BP 125/80 RR 12 O2Sat 100% room air. The conjunctiva appear erythematous. His knees and ankles have small effusions, mild erythema and are mildly tender to palpation with full range of motion. His genital exam is notable for normal male genitalia with whitish urethral discharge.
1. What is your differential diagnosis?
-gonococcal arthritis, reactive arthritis, septic arthritis
2. What would you like to do next?
-check FBP, ESR, urethral culture, stool culture consider x-ray and arthrocentesis if diagnosis unclear
3. What is clinical presentation of reactive arthritis?
-painful asymmetric oligoarthritis mainly affecting knees, ankles and feet
-most common in men
-classic triad is arthritis, urethritis and conjunctivitis
-can develop “sausage digits” of the extremities, sacroiliitis, enthesopathy
-cutaneous manifestations: balantitis circinata (shallow painless ulcers of glans penis and urethral meatus), karatoderma blenorrhagica (hyperkeratotic skin lesions on soles of feet,scrotum, palms, trunk, scalp), stomatitis, superficial oral ulcers
-most patients recover within 6 months but can persist for months to years and can recur
4. What is the etiology of reactive arthritis?
-occurs after 1% of cases of nongonococcal urethritis and 2% of enteric infections (most commonly Yersinia enterocolitica, Shigella flexneri, Campylobacter jejuni and Salmonella species
-can also be secondary to IDS
5. What is the treatment?
-NSAIDs for pain relief
-antibiotic therapy aimed if evidence of current infection
Other seronegative arthropathies include ankylosing spondylitis, psoriatic arthritis, IBD-associated arthritis.
Hemarthosis is another cause of joint pain and swelling. Most common causes are trauma and hemophilia. Joint fluid analysis should reveal bloody fluid and many RBC. Send the fluid for a hematocrit as well. Repeated hemarthoses can lead to hemosiderin deposition and joint destruction/deformities. Note: sickle cell, Lyme disease, rheumatic fever not covered here.
