A 20-year-old female presents with a butterfly-shaped rash across her face, painful joints, fever, and laboratory findings showing positive ANA and anti-dsDNA antibodies. What is the most likely diagnosis?
A. Systemic sclerosis
B. Systemic lupus erythematosus
C. Rheumatoid arthritis
D. Polymyalgia rheumatica
E. Gouty arthritis
Correct Answer: B. Systemic lupus erythematosus (SLE)
Explanation:
The presentation of butterfly-shaped rash, painful joints, fever, and the presence of positive ANA (antinuclear antibody) and anti-dsDNA (anti-double-stranded DNA antibodies) strongly suggests Systemic Lupus Erythematosus (SLE).
Key Features Supporting SLE:
- Butterfly Rash:
- This is a characteristic feature of SLE, often seen across the cheeks and nose, forming a “butterfly” shape. It is a distinctive rash that is photosensitive and typically appears in the context of systemic disease activity.
- Joint Pain:
- Arthralgia (joint pain) is common in SLE, affecting the small joints of the hands and wrists. It is often accompanied by mild inflammation and can lead to discomfort, though it typically does not cause significant joint damage in early stages.
- Positive ANA and Anti-dsDNA:
- ANA is a screening test for SLE, and a positive result is found in the vast majority of patients.
- Anti-dsDNA antibodies are more specific for SLE and are associated with renal involvement and disease activity.
- Fever:
- Systemic involvement in SLE often leads to low-grade fever, reflecting ongoing inflammation and immune activation.
Why Other Options Are Incorrect:
A. Systemic Sclerosis:
- Also known as scleroderma, this autoimmune disease involves skin tightening and fibrosis. It can cause joint pain, but it typically does not present with a butterfly rash or positive anti-dsDNA antibodies. The skin changes in systemic sclerosis are more pronounced and affect the extremities.
C. Rheumatoid Arthritis:
- While rheumatoid arthritis can cause painful joints and fever, it is not typically associated with a butterfly rash or positive anti-dsDNA antibodies. Rheumatoid arthritis primarily affects the small joints of the hands and feet, but the systemic features are different from SLE.
D. Polymyalgia Rheumatica:
- Polymyalgia rheumatica presents with muscle pain and stiffness, typically in the shoulder and hip girdles. It does not cause a butterfly rash or positive anti-dsDNA antibodies, making it unlikely in this case.
E. Gouty Arthritis:
- Gout typically presents with acute, severe joint pain, especially in the big toe. It is characterized by elevated serum uric acid levels, not by a butterfly rash or positive ANA/anti-dsDNA.
Further Investigations:
To confirm the diagnosis of SLE and assess the extent of organ involvement, the following investigations may be performed:
- Complete Blood Count (CBC):
- To check for anemia, leukopenia, or thrombocytopenia, which are common in SLE.
- Urinalysis:
- To check for proteinuria or hematuria, which could indicate renal involvement (lupus nephritis).
- Complement Levels (C3, C4):
- These levels are often low in active SLE, reflecting ongoing immune complex deposition.
- Chest X-ray or Echocardiogram:
- To screen for possible pulmonary involvement (e.g., pleuritis or interstitial lung disease) and cardiac complications (e.g., pericarditis).
Management:
Treatment for SLE typically involves:
- Non-steroidal anti-inflammatory drugs (NSAIDs):
- To manage joint pain and inflammation.
- Hydroxychloroquine:
- A disease-modifying antirheumatic drug (DMARD) used to control cutaneous and arthritic manifestations of SLE.
- Corticosteroids:
- In cases with more severe systemic involvement (e.g., renal or CNS involvement), steroids may be used.
- Immunosuppressive Therapy:
- For patients with significant organ involvement, medications like azathioprine, cyclophosphamide, or mycophenolate mofetil may be prescribed.
Conclusion:
This 20-year-old female’s presentation with butterfly rash, joint pain, fever, and positive ANA/anti-dsDNA antibodies points to Systemic Lupus Erythematosus (SLE). Early diagnosis and management are essential to prevent complications such as renal or cardiovascular involvement.