INTRODUCTION:
Necrobiosis lipoidica (NL) is a relatively rare granulomatous skin
disorder, associated with dermal collagen degeneration. When develops in
the context of diabetes, it is specifically referred to as necrobiosis
lipoidica diabeticorum (NLD).
Skin involvement is commonly characterized by well-defined
brownish-yellow indurated plaques with overlying telangiectasias,
violaceous borders and atrophic center. It mainly affects the pretibial
area but can also present in the upper extremities, trunk, genitalia,
face and scalp (1, 2).
Moreover, morphea (also known as localized scleroderma), is a rare and
self-limited autoimmune skin disorder of excess collagen production and
deposition, causing inflammation and fibrosis of dermis and subcutaneous
tissues. Plaque type morphea as the most common form of localized
scleroderma, initially presents as slightly elevated, reddish or
purplish plaques that gradually expand outward in a centrifugal pattern.
In the later stages of the disease, skin lesions develop into
dyspigmented, atrophic and sclerotic plaques. Commonly involved areas
include the trunk, as well as the inframammary and inguinal regions.
Both necrobiosis lipoidica and morphea are non-infectious inflammatory
dermatoses of unclear pathogenesis and etiology(1, 3). As of now, only
four cases of concurrent necrobiosis lipoidica (NL) and morphea have
been documented in the literature. One case was detailed in a case
report, while the other three were included in a retrospective study (4,
5). Herein, we document a case of concomitant NL and morphea in a
43-year-old non-diabetic woman with a history of NL on her elbow,
recently developed a plaque-type morphea on her trunk. We also review
the literature on other dermatoses that have been reported to coexist
with NL.