The final diagnosis is clinical and made after ruling out other possible causes of
joint swelling. It calls for a high degree of suspicion, especially in individuals who have progressive
soft tissue swelling without any pain, soreness, or diminished function. Unless clinically indicated, laboratory testing such as
extractable nuclear antigen test,
rheumatoid factor,
C-reactive protein,
complete blood count, and
antinuclear factor are not required. A thickening of the
dermis, possibly associated with a benign proliferation of
fibroblasts, and an increase in
collagen fibers that extend to the subcutaneous cellular tissue are the most common histological findings. An
X-ray examination shows no abnormalities in the
periosteum or bones in pachydermodactyly patients. Additionally, no changes are seen in the
synovium or joints during
ultrasound. Chen et al. published a diagnostic criterion that consists of six elements: the patient having no symptoms; there being no stiffness in the morning; no restriction on movement; swelling on the lateral aspect of the finger; normal laboratory values; and
soft tissue swelling on
radiography. Differential diagnoses include
rheumatoid arthritis,
acromegaly,
juvenile idiopathic arthritis,
pachydermoperiostosis,
knuckle pads, and juvenile digital
fibromatosis. == Treatment ==