Capillary microscopy during eosinophilic fasciitis in 15 patients: distinction from systemic scleroderma

Eosinophilic fasciitis (EF) is a newly recognized syndrome that bears much discussion in regard to its distinction from progressive systemic sclerosis (PSS). In vivo microscopic examination of the nailbed capillaries has elicited the description of a characteristic vascular pattern seen in PSS dermatomyositis, and mixed connective tissue disease. To clarify the capillaroscopic aspects of this syndrome and to seek criteria distinguishing it from PSS, we performed nailbed capillary microscopy in 15 patients with EF and compared the results of this examination with those in 98 patients with PSS and those in 75 normal control subjects.

The diagnosis of EF was made in 15 patients aged 25 to 69 years (average 43 years) who had an acute course, with painful edema and subcutaneous sclerotic induration sparing the extremities. There was a peripheral hypereosinophilia in all 15 patients. Twelve underwent muscle or deep cutaneous biopsy, including the fascia. Nine of these had fascial thickening, and an inflammatory cell infiltrate was observed in eight. The diagnosis of PSS was made in 98 patients, according to the usual criteria. Seventy-five normal control subjects were examined. All the capillaroscopic examinations were performed by one observer.

None of the patients in the EF group had a scleroderma-like capillaroscopic pattern. Thirteen had normal results of capillary microscopy. Two had a nonspecific organic microangiopathic picture. In the group of 98 patients with PSS, 89 had numerous megacapillaries (p less than 0.001), seven had a nonspecific organic microangiopathic pattern, and two had normal findings (p less than 0.001). In the whole group of 75 control subjects, the features were normal.

Our results show a clear distinction between the results of capillary microscopy in cases of EF and PSS. The normal pattern in EF seems to be another argument for its differentiation from PSS.