Residency Program - Case of the Month

Clinical History

The patient is a 76-year-old male with a history of diabetes mellitus and bullous pemphigoid. He presented with diffused erythema, edema and slight fissuring in both palms without active blisters. CBC analysis revealed a marked lymphocytosis with predominantly mature lymphocytes (WBC: 37.8 K/MM3 , Lymphocytes: 31.8 K/MM3).

Flow cytometry of the peripheral blood was performed and showed markedly elevated CD4:8 ratio (32:1). This CD4+ population was negative for CD25-, CD26-, CD30-, and showed aberrant T-cell antigen drop out (subset CD7-). There was no evidence of monotypic B-cell population and no blasts.

Pathologic Findings

Sections of the punch biopsy taken from the right palm are shown below.

Click on image to enlarge.

Figure 1: Right palm (biopsy site shown as A) with diffused erythema, edema and slight fissuring

Figure 2: Right palm. Dermal lymphoid infiltrate with epidermotropism. H&E 40x

Figure 3: Right palm. A closer view at the atypical lympoid infiltrate with epidermotropism. H&E 200x

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