Case Study:

This is a 28 year old woman who presents with a reticulated rash on her chest. She has been on topical and oral steroids without resolution. Doxycyline seemed to make it worse. The area is photosensitive and has been present for 1 year without resolution and without new lesions.

Diagnosis:

Reticular Erythematous Mucinosis

This case brings together a variety of interesting clinical and histopathological features. The name of the disease perfectly describes both features.

There is nothing specific about a reticulated erythematous rash. It may be a primary skin disease or part of a systemic disorder. Classic diagnoses include:

Confluent and reticulated papillomatosis
Cutis marmorata/Livedo reticularis
Erythema ab igne
Lichen planus-Wickham striae
Lupus erythematosus and variants
Reticular erythematous mucinosis
Tinea versicolor

Similarly, the histopathologic findings of a superficial and deep perivascular and periadnexal lymphocytic infiltrate with dermal mucinosis may be visualized with several dermatological disorders including:

Lupus
Jessner's lymphocytic infiltrate
Polymorphous light eruption
Reticular erythematous mucinosis

Since the common link in these two categories is lupus erythematosus, it was critical to exclude this latter disease. In this current case, the patient's ANA was negative. A biopsy for direct immunofluorescence was not performed. It should be noted that some investigators do believe REM to be a variant of lupus.

This case illustrates the cooperative marriage between the clinical and histopathologic findings, to arrive at a diagnosis. Now, if only we could just transfer this harmony to humans!

Clinical photo and case history submitted by Elizabeth Lener, M.D., Ladera Ranch, CA.

Archived Case Studies

References:

The Doctor's Doctor-Reticular Erythematous Mucinosis

Comments:

REM is considered a variant of LE by many due to the epidemiology (females mainly, photosensitivity and histologic findings.