Persistent pruritic eruptions (PPE) are common among our patients with adult-onset Still disease (AOSD). We aimed to characterize the clinicopathologic features of the AOSD-associated evanescent and persistent rashes.
We reviewed the clinicopathologic features of the skin lesions from all AOSD cases diagnosed in our hospital during 1988 to 2009. The diagnoses were based on Yamaguchi criteria for AOSD.
Altogether, there were 36 patients (6 men and 30 women) with age of onset ranging from 17 to 67 years (average 35.7 years). Evanescent rash was recorded in 31 patients (86%) and PPEs in 28 (78%). PPEs usually appeared at the disease onset and manifested as widespread, pruritic, erythematous urticarial or violaceous to brownish flat-topped (lichenoid) papules and plaques over the trunk, neck, face, and extensor sides of the extremities. PPEs were classified clinically as urticarial papules (n = 21), lichenoid papules (n = 18), prominent linear and dermographism-like (n = 11), dermatomyositis-like (n = 7), prurigo pigmentosa-like (n = 4), and lichen amyloidosis-like (n = 2). The clinical activity score was 5.78 ± 1.11 (range 4 to 8) for the series and 6.57 ± 0.98 and 5.57 ± 1.07, respectively, for the groups with and without dermatomyositis-like PPE (P = 0.0314). Five patients died, 3 of them with dermatomyositis-like PPE. Histopathologically, the evanescent rash (8 specimens) showed a superficial perivascular infiltrate of lymphocytes and neutrophils, whereas the PPEs (32 specimens) revealed solitary or cluster necrotic keratinocytes in the superficial epidermis with infiltration of lymphocytes and neutrophils in the upper and mid dermis.
PPEs were very common among our patients with AOSD. Recognition of the characteristic clinical and pathologic features of PPE can facilitate diagnosis of AOSD. Therefore, biopsy of atypical eruptions in AOSD patients is recommended because it is likely that the highly distinctive histopathologic features will allow these eruptions to be readily classified.