Management of a Unique Presentation of a Common Dermatologic Condition

Abstract

Context: Skin rashes are a common complaint seen in the primary care setting. There are many dermatologic conditions which a primary care provider (PCP) should be able to recognize and manage. One such condition is granuloma annulare (GA), which commonly presents as smooth, annular plaques on the trunk and/or extremities. Rashes like GA rarely present as unique variants and may be difficult for PCPs to determine from patient history and physical exam alone. Patch granuloma annulare (patch GA) is an example that may clinically mimic a cutaneous lymphoma known as mycosis fungoides (MF). PCPs should ideally be able to recognize the utility of performing a skin biopsy and/or referring the patient to a dermatologist when history and physical exam alone are insufficient. The histologic findings of skin biopsies often become essential in establishing a proper diagnosis and guiding patient management in unique dermatologic variants.

Example case: The patient in this clinical practice report is a Caucasian female in her late 60s who presented to a dermatology clinic with a two-year history of a worsening widespread eruption on her trunk and extremities. She had been evaluated previously by her PCP about 4 months prior and, without obtaining skin biopsies, treated her with a medium potency topical corticosteroid cream. The eruption had spread over her hips, buttocks, back, thighs, wrists, and elbows. Multiple skin biopsies of affected sites were taken by the second author and revealed findings consistent with patch GA. The patient was started on topical betamethasone dipropionate 0.05% ointment twice daily and noted marked improvement of her symptoms.

Conclusions: Although GA is a benign condition of the skin that may be readily detected by PCPs, skin biopsies may be necessary to establish a proper diagnosis when this condition presents as a unique variant (e.g., patch GA). Therapy for patch GA often begins with a trial of high-potency topical steroid therapy in combination with ultraviolet light exposure, depending on disease severity and patient preference. Early evaluation with a skin biopsy by her PCP or an earlier referral to a dermatologist to have skin biopsies performed likely would have helped establish a prompter diagnosis and treatment plan for this patient.

Keywords: biopsy; corticosteroid; granuloma annulare; macrophage; patch granuloma annulare; steroid.

Figure 1.. An example of GA on the dorsum of the hand presenting as multiple, red papules.

Retrieved via public domain Wikipedia.

Figure 2.. Photographic images of red-brown patches on the bilateral posterior thighs (Left), anterior abdominal skin folds near the umbilicus bilaterally (upper Right), bilateral anterior wrists (upper Middle), and bilateral flanks (lower Middle/Right). Images were cropped and modified using the “Snipping Tool” feature on Microsoft.

These photographs were taken after the patient signed a written consent form releasing her photos for educational purposes and publication in the Spartan Medical Research Journal.

Figure 3.. (Left) Histopathologic examination with H&E staining at 10x magnification of one of the punch biopsies taken. (Right) Higher power analysis shows central necrobiosis and mucin deposition. The light purple cells in both images are histiocytes (circle in Right) and they are coalescing around pinkish-blue degraded collagen (square in Right).

Images were cropped and modified using the “Snipping Tool” feature on Microsoft.

Figure 4.. Example H&E of granuloma annulare. Basophilic components (example circled) often represent genetic material, such as DNA within a cell’s nucleus. Eosinophilic components (example squared) often represent proteins, such as intracellular organelles or the collagen fibrils within the extracellular matrix.

Image retrieved via public domain Wikipedia.