The routine use of iron stain for biopsies of dermatoses of the legs

Abstract

Our goal was to study the utility of the routine use of the Gomori iron stain in the evaluation of leg biopsies of inflammatory lesions. One hundred consecutive skin biopsies from the legs were evaluated with hematoxylin and eosin and Gomori iron stains. Iron positivity was semi-quantitatively graded from trace to 4+. Forty-two (42) cases were positive with the Gomori iron stain as follows: stasis dermatitis (14), Schamberg's disease (7), folliculitis (2), psoriasis (2), trauma (2), arthropod bite (2), allergic contact dermatitis (2), lichen simplex chronicus (1), senile purpura (1), vascular ectasia (1), lobular capillary hemangioma (1), scar (1), pretibial pigmented patches (1), tinea (1), lentigo maligna (1), traumatic fat necrosis (1), lichen planus (1) and fixed drug eruption (1). Twelve of 14 cases of stasis dermatitis had 2+ or greater iron staining; 8 cases were 3+ or 4+. All other diagnoses had trace or 1+ staining for iron except for one scar (2+). One of 19 samples (5.3%) of 'normal' leg skin controls showed iron stain positivity, and was graded as trace. After correcting for iron staining in 5.3% of normal leg skin controls, we observed Gomori iron positivity in 36.7% of 100 consecutive leg biopsies. We suggest that routine application of an iron stain on biopsies of dermatoses from the legs is useful. Stasis dermatitis and Schamberg's disease are the most frequent iron positive diagnoses, and the diagnosis is aided by the pattern of hemosiderin deposition. Negative iron stain is also useful in suggesting the presence of melanin pigment in macrophages in lichenoid and other dermatoses. To confirm a truly negative iron stain, study of the section at ×400 rather than ×100 is recommended.