10 dactylitis facts
In this article we will describe 10 dactylitis facts.
Typical dactylitis
Dactylitis is a syndrome (group of diseases) – i.e. it has causes.
Key Points
- Dactylitis is a medical condition characterised by diffuse swelling of an entire finger or toe; giving it a sausage-like appearance -.often associated with inflammatory conditions.
- Dactylitis is also known as ‘sausage digit/finger’ or ‘sausage toe’. It usually affects most fingers (and/or toes), but can affect one more than another.
- It is commonly seen in spondyloarthropathies (especially psoriatic arthritis) and sickle cell disease.
- Diagnosis is clinical, supported by imaging and laboratory tests to identify underlying conditions.
- Treatment involves addressing the primary cause, with anti-inflammatory medications and disease-modifying agents.
- Early recognition and management of the underlying condition are crucial to prevent complications and improve patient outcomes.
1. Definition
- Dactylitis refers to a diffuse swelling of an entire digit (finger or toe) that gives it a characteristic ‘sausage-like’ appearance. It is a sign rather than a diagnosis, often indicating an underlying systemic condition.
- The swelling involves soft tissues, including skin, tendons, and synovium, and is usually associated with pain and inflammation.
2. Epidemiology
- Psoriatic Arthritis (PsA): Dactylitis is a hallmark feature and occurs in around 30-50% of patients with PsA during the course of the disease.
- Sickle Cell Disease: Often presents as a painful swelling in children, with an incidence that peaks between 6 months and 2 years of age.
- Other Conditions: Dactylitis is also observed in other inflammatory conditions, such as ankylosing spondylitis, reactive arthritis, and certain infectious diseases.
3. Risk factors
- Underlying Inflammatory Disease: Conditions such as PsA, ankylosing spondylitis, and inflammatory bowel disease (IBD) can predispose to dactylitis.
- Genetic Predisposition: Patients with HLA-B27 positivity are more likely to develop spondyloarthropathies, which can manifest with dactylitis.
- Sickle Cell Disease: The presence of sickle cell anemia increases the risk, especially in children.
- Infections: Certain bacterial or fungal infections can lead to dactylitis, particularly in immunocompromised individuals.
4. Causes
Dactylitis can be caused by several conditions, which can be broadly classified as follows:
Inflammatory
- Psoriatic Arthritis: Dactylitis occurs due to inflammation of the flexor tendons and synovium (tenosynovitis), as well as periarticular tissues.
- Reactive Arthritis: A post-infectious inflammatory condition that can cause joint and soft tissue inflammation.
- Ankylosing Spondylitis and Other Spondyloarthropathies: Can lead to dactylitis, especially in conjunction with other features like sacroiliitis.
- Sarcoidosis: Sometimes presents with dactylitis, particularly in the context of Löfgren’s syndrome.
Non-Inflammatory
- Sickle Cell Disease: Caused by vaso-occlusive crises that lead to bone infarction and inflammation, particularly in the small bones of the hands and feet in young children (hand-foot syndrome).
- Infections: Tuberculosis, leprosy, and other bacterial or fungal infections can cause localised swelling resembling dactylitis.
5. Symptoms
- Swelling: Diffuse swelling of the entire digit, often resembling a sausage. It is usually quite rapid and may be accompanied by pain, tenderness, and stiffness in the affected digit.
- Pain: Varies depending on the cause; may be acute and severe in sickle cell crises or more chronic in inflammatory arthritis.
- Redness and Warmth: Common in cases of active inflammation, particularly in psoriatic arthritis.
- Limited Range of Motion: Patients may experience stiffness or difficulty moving the affected digit.
6. Diagnosis
Clinical Assessment
- History: Ask about the duration of swelling, presence of pain, stiffness, history of psoriasis, previous joint or back pain, and family history of arthritis or autoimmune conditions.
- Physical Examination: Look for the classic ‘sausage digit’ appearance. Check for other signs of systemic illness, such as skin rashes (psoriasis), nail changes (pitting, onycholysis), or signs of systemic involvement (uveitis, sacroiliitis).
Investigation
- Blood Tests:
- Inflammatory Markers: Elevated ESR and CRP suggest active inflammation.
- Rheumatological Tests: Rheumatoid factor (RF), anti-CCP antibodies, and HLA-B27 typing can help in diagnosing specific inflammatory conditions.
- Full Blood Count: To check for anaemia and leucocytosis, which may suggest an underlying systemic condition.
- Sickle Cell Testing: Hemoglobin electrophoresis or a sickle cell test if sickle cell disease is suspected.
- Imaging:
- X-rays: May show periarticular erosions, joint space narrowing, or new bone formation in cases of psoriatic arthritis.
- Ultrasound: Useful for assessing soft tissue swelling, tenosynovitis, and guiding joint or tendon sheath aspiration.
- MRI: More sensitive than x-rays and can detect soft tissue and bone marrow inflammation, particularly useful for early diagnosis in spondyloarthropathies.
- Other Tests:
- Joint Aspiration and Fluid Analysis: For suspected infections or crystal-induced arthritis.
Differential diagnosis
- Infectious Causes:
- Septic Arthritis or Tenosynovitis: Presents with pain, warmth, and erythema, often with a history of trauma or infection.
- Tuberculous Dactylitis (Spina Ventosa): Rare but should be considered in endemic areas or immunocompromised patients.
- Rheumatological Conditions:
- Rheumatoid Arthritis: Typically presents with symmetric small joint involvement, but dactylitis is rare.
- Gout and Pseudogout: Acute onset of pain and swelling, but usually localised to a single joint rather than the entire digit.
- Vascular and Haematological Conditions:
- Sickle Cell Disease: In children, acute dactylitis (hand-foot syndrome) may be the first presentation of the disease.
- Sarcoidosis: Can cause a range of systemic symptoms, including arthritis and dactylitis, particularly in Löfgren’s syndrome.
7. Treatment
Addressing Underlying Cause
- Psoriatic Arthritis and Other Spondyloarthropathies:
- Nonsteroidal Anti-Inflammatory Drugs (NSAIDs): First-line treatment for pain and inflammation.
- Disease-Modifying Anti-Rheumatic Drugs (DMARDs): Methotrexate, sulfasalazine, and leflunomide may be used.
- Biologic Agents: TNF-alpha inhibitors (e.g. etanercept, infliximab) are effective in patients not responding to conventional DMARDs.
- Sickle Cell Disease:
- Pain Management: Analgesics (e.g. NSAIDs, opioids) are essential for managing vaso-occlusive crises.
- Hydration and Oxygenation: Important to reduce the risk of further crises.
- Disease-Modifying Treatment: Hydroxyurea can reduce the frequency of painful crises and dactylitis episodes.
- Infectious Causes:
- Antibiotics or Antitubercular Therapy: Depending on the identified organism, prompt antimicrobial treatment is necessary.
- Surgical Drainage: Required for abscesses or severe infections that do not respond to antibiotics alone.
Symptomatic
- Local Steroid Injections: Can be used in cases of inflammatory dactylitis, especially in psoriatic arthritis.
- Physiotherapy: To maintain joint function and mobility.
8. Complications
- Joint Damage and Deformities: Particularly in untreated or poorly managed cases of psoriatic arthritis and rheumatoid arthritis.
- Chronic Pain and Stiffness: Ongoing inflammation can lead to long-term functional impairment.
- Systemic Complications: In cases of underlying systemic diseases, such as sickle cell crises affecting multiple organs.
9. Prognosis
- Variable Outcomes: The prognosis depends on the underlying cause. Early diagnosis and effective management of the primary condition can significantly improve outcomes.
- Inflammatory Conditions: With appropriate treatment, many patients achieve good control of symptoms. However, chronic conditions like psoriatic arthritis may have periods of flare-ups and remissions.
- Sickle Cell Disease: Prognosis has improved with better management of vaso-occlusive crises and the use of hydroxyurea.
10. Prevention
- Management of Underlying Conditions:
- Rheumatological Diseases: Early initiation of DMARDs or biologic agents can prevent the development of dactylitis in psoriatic arthritis.
- Sickle Cell Disease: Use of hydroxyurea and preventive strategies, including avoiding triggers for vaso-occlusive crises, can reduce the incidence of dactylitis.
- Lifestyle Measures:
- Diet and Exercise: Maintaining a healthy lifestyle can help reduce the severity of inflammatory conditions.
- Avoiding Smoking: Important for patients with spondyloarthropathies and sickle cell disease, as smoking can exacerbate symptoms.
Summary
We have described dactylitis and its symptoms, causes, and treatment. We hope you understand it better now.
Other resource
MyHSN dactylitis podcast (2024) – 10 min, 15 sec
