Dactylitis is swelling of the digits and is often known as “sausage digits” because the bloating causing the fingers or toes to resemble small sausages. Many conditions and diseases are capable of causing dactylitis, including several infections and types of arthritis. The mechanisms that lead to the swelling can also vary.
Symptoms and Effects
The main symptom of dactylitis is swelling of the hands and fingers. However, several other effects can accompany the inflammation. Most commonly, the joints feel warm. As the digits swell, they can become difficult to move. Pain originating from the affected areas is also common. Various other symptoms may develop depending on the specific cause. Without treatment, symptoms worsen, and loss of function becomes more likely.
Several types of spondyloarthritis can cause dactylitis, with the most common being psoriatic arthritis. These two conditions occur together so often that doctors consider dactylitis as an indicator[for]. Psoriatic arthritis-related dactylitis primarily affects the feet. Reactive arthritis, another type of spondyloarthritis, can also lead to dactylitis. However, the cause is an infection that results in synovial swelling. Genital, urinary tract, and intestinal infections can all be responsible for this.
Causes: Sickle Cell Disease
One of the leading causes of dactylitis is sickle cell disease. Red blood cells generally have a [flexible]disc-like shape, but sickle cell disease changes the hemoglobin protein to cause inflexible and sickle-shaped blood cells. These rigid sickle-shaped cells can obstruct blood vessels, slowing or blocking blood flow. In many cases, dactylitis is the first symptom of sickle cell disease in infants and young children.
One of the most common infectious causes of dactylitis is congenital syphilis. Pregnant individuals can pass syphilis on to the fetus, resulting in a congenital form. Babies born with congenital syphilis can develop dactylitis in their fingers and toes. While dactylitis may affect only one side of the body, syphilitic dactylitis usually affects both sides.
Causes: Other Infections
Beyond syphilis, many other infections can cause dactylitis. For example, blistering distal dactylitis can result from bacterial skin infections, manifesting as large, fluid-filled, painful lesions on the fingers and toes. Infectious conditions like tuberculosis and leprosy are other rare causes.
Doctors can usually diagnose swelling just by observing a patient’s digits. However, they may need to perform imaging tests like MRIs, ultrasounds, ]and x-rays to determine if the symptom is specifically dactylitis. Additionally, an integral part of the diagnostic process for dactylitis is discovering the underlying cause. This may require additional blood tests or joint fluid tests. Ignoring the underlying condition could lead to major complications, and dactylitis could return even after treatment.
Missing the Diagnosis
Sometimes, doctors can mistake dactylitis for other inflammatory conditions, and conversely, other issues for dactylitis. Sickle-cell dactylitis often resembles acute osteomyelitis, leukemia, or cellulitis. Rheumatoid arthritis causes swelling of the fingers that looks similar to dactylitis but is clinically distinct. Experts can misdiagnose some rarer forms of dactylitis as psoriasis, infections, or even malignancies.
It is extremely difficult to objectively determine the severity of a case of dactylitis, though experts have historically used several methods. One option is the Leeds Dactylitis Index, which rates each digit with a tenderness score and whether or not swelling is present. A higher score signifies measurably worse tenderness. Medical imaging can sometimes determine the severity, as well. Medical professionals have attempted to develop other evaluation methods, though these still lack testing in routine clinical practice.
Doctors primarily treat dactylitis by targeting the cause. Cases that result from an infection require antibiotics. Sickle-cell dactylitis is self-limiting, meaning that treatment involves alleviating the pain rather than the swelling itself. Other forms of dactylitis may require immunosuppressive medications to combat the inflammation. Non-steroidal anti-inflammatory medications and corticosteroid injections can also temporarily reduce the swelling. New research indicates that biologic medications are effective in improving symptoms in some patients.
Once a medical professional treats the underlying cause, most cases of dactylitis improve. For incurable chronic issues, a person with dactylitis has a few options. Working with a physical therapist may help regain lost function in the affected digits. Losing excess weight can lessen the severity of the symptoms and improve the effectiveness of medications.