What investigations are indicated for a 15‑year‑old Black African male with intermittent swelling and pain of both hands without fever?

Investigation of Bilateral Hand Pain and Swelling in a 15-Year-Old Black African Male

Start with plain radiographs of both hands (posteroanterior, lateral, and oblique views) as the essential first-line investigation, followed by targeted laboratory testing including anti-CCP antibodies, rheumatoid factor, complete blood count with peripheral smear, ESR, CRP, and consideration of hemoglobin electrophoresis given the patient's ethnicity and age. 1, 2

Initial Imaging

Plain radiographs are the mandatory first imaging study for any patient presenting with chronic or intermittent hand pain and swelling. 1

• The American College of Radiology establishes that standard three-view radiographs (posteroanterior, lateral, and oblique) allow assessment of alignment, joint spaces, erosions, soft tissue swelling, and mineralization patterns 1
• Radiographs of affected joints should be performed at baseline and repeated within 1 year if disease persists 1
• Look specifically for: erosive changes, joint space narrowing, soft tissue swelling, periosteal reaction, or bone infarcts 1, 3

Essential Laboratory Investigations

Autoimmune/Inflammatory Markers

Anti-CCP antibody testing is the first-line serologic test for suspected inflammatory arthritis due to its 95% specificity for rheumatoid arthritis, allowing early detection before irreversible joint damage occurs. 2

• Rheumatoid factor (RF) should be obtained as a complementary marker if anti-CCP is negative, as RF-negative RA exists 1, 2
• ESR and CRP are essential but nonspecific markers—importantly, normal inflammatory markers do NOT exclude inflammatory arthritis, as erosive hand osteoarthritis commonly presents with normal or only mildly elevated CRP 4, 5

Hematologic Evaluation

Given the patient's Black African ethnicity and adolescent age, a complete blood count with peripheral smear and hemoglobin electrophoresis are critical to exclude sickle cell disease and thalassemia, which commonly present with hand involvement. 3

• Sickle cell disease characteristically affects the hand in adolescents with the "hand-foot syndrome" and can present with intermittent painful swelling 3
• Thalassemia involves the hand in 100% of cases with characteristic bone changes including osteopenia, widening of marrow spaces, and cyst-like changes 3
• These hematologic conditions must be excluded before attributing symptoms to primary rheumatologic disease 3

Additional Targeted Testing

• HLA-B27 testing should be considered if spondyloarthritis is suspected, particularly if the patient is RF and anti-CCP negative 1
• Uric acid level to exclude gout, though less common in this age group 4
• Consider ANA if systemic lupus erythematosus is in the differential 6

Advanced Imaging (If Initial Workup Is Inconclusive)

MRI of the hands and wrists without IV contrast is the definitive advanced imaging modality if diagnosis remains unclear after initial radiographs and laboratory testing. 1, 4

• MRI can detect bone marrow edema, synovitis, and early erosive changes not visible on plain films 1, 4
• Bone marrow edema in metacarpophalangeal joints is significantly more frequent in rheumatoid arthritis and predicts progression from undifferentiated arthritis to RA 1, 6
• However, MRI cannot reliably distinguish early RA from SLE or Sjögren syndrome in patients without radiographic erosions 6
• Ultrasound with power Doppler can detect synovitis and joint effusion but remains operator-dependent and is not yet recommended for routine diagnostic use in undifferentiated arthritis 1, 7

Critical Diagnostic Pitfalls to Avoid

• Do not assume normal ESR/CRP excludes inflammatory arthritis—erosive inflammatory osteoarthritis and early RA can present with normal inflammatory markers 4, 5
• Do not overlook hematologic causes in a Black African adolescent—sickle cell disease and thalassemia must be actively excluded 3
• Absence of fever does not exclude serious pathology—many inflammatory arthritides and hematologic conditions present without fever 4, 3, 5
• Symmetric hand involvement in an adolescent raises concern for juvenile idiopathic arthritis or early RA, both requiring aggressive early treatment to prevent joint destruction 2, 8

Diagnostic Algorithm Summary

1. Obtain plain radiographs of both hands (three views) immediately 1
2. Order anti-CCP antibodies, RF, CBC with smear, hemoglobin electrophoresis, ESR, CRP, and uric acid 1, 2, 3
3. If seronegative and clinical suspicion for spondyloarthritis exists, add HLA-B27 1
4. If diagnosis remains unclear after initial workup, proceed to MRI of hands and wrists without contrast 1, 4
5. Repeat radiographs within 1 year if symptoms persist to assess for progression 1