The histopathological differentiation between palmar psoriasis and hand eczema: A retrospective review of 96 cases.

BACKGROUND

The histopathologic differences among palmar psoriasis (PP), hand eczema (HE), and hyperkeratotic hand dermatitis (HHD) have been poorly described.

OBJECTIVES

We sought to distinguish among PP, HE, and HHD on a histopathologic basis.

METHODS

We retrospectively analyzed the histology of hematoxylin-eosin-stained sections obtained from 96 patients diagnosed with PP, HE, or HHD.

RESULTS

The patients were divided into 4 subgroups: PP (n = 16, group A), HE without atopic or nummular dermatitis (n = 41, group B), HE with atopic or nummular dermatitis (n = 14, group C), and HHD (n = 25, group D). Loss of the granular layer (group A 62.5%, group B 24.4%, group C 0%) was more consistent with a diagnosis of PP (P = .047) than HE (P = .002). Psoriasiform epidermal hyperplasia (group B 36.6%, group C 35.7%, group D 72.0%) favored a diagnosis of HHD (P = .01) over HE (P = .043).

LIMITATIONS

Limitations of this study include its retrospective nature and small sample size.

CONCLUSION

Our study demonstrated that a significant difference exists in the thickness of the granular layer between PP and HE, which might be helpful in differentiating between these 2 conditions. There was no difference between PP and HHD.