Histopathologic features of necrobiosis lipoidica

Abstract

Background Necrobiosis lipoidica (NL) is an uncommon granulomatous dermatosis that can occur in patients with or without associated diabetes mellitus (DM). Prior studies have attempted to determine distinctive histopathologic features of NL in patients with and without DM. Methods A retrospective review of 97 patients with NL was performed to determine the similar and distinctive histopathologic features in patients with DM and without DM. Results Of the 97 patients, 32% (n = 31) had DM. Epidermal acanthosis was seen more commonly in diabetics than nondiabetics (32.3% vs. 12.1%; p = 0.017). Naked (sarcoidal/tuberculoid) granulomas were more frequently observed in nondiabetics than diabetics (22.7% vs. 3.2%; p = 0.016). Eosinophils were more common in nondiabetics than diabetics (38.5% vs. 9.7%; p = 0.004), while neutrophilic infiltration was more common in diabetics than nondiabetics (45.2% vs. 17.5%; p = 0.004). Conclusions This study corroborates well‐documented histopathologic features of NL and shows distinctive histopathologic features of NL among patients with DM‐I, DM‐II, and without DM. These results support the hypothesis that there are different underlying drivers of NL between diabetics and nondiabetics.

Characteristics of ulcerated and non‐ulcerated necrobiosis lipoidica

“…1,3 It has been suggested that there are different pathogenetic drivers of NL in patients with DM and those without DM, and distinctive histopathologic features of these groups have been reported. 1,8,21 Specifically, NL patients without DM have more frequent naked (sarcoidal/tuberculoid) granulomas (23% vs. 3%), more frequent eosinophils (39% vs. 10%), more frequent acanthosis (32% vs. 12%), and less frequent neutrophilic infiltration (18% vs. 45%) compared to NL patients with DM. 21 These prior studies have not investigated whether different histopathologic findings correspond to differences in ulceration rates.…”

“…Specifically, NL patients without DM have more frequent naked (sarcoidal/tuberculoid) granulomas (23% vs. 3%), more frequent eosinophils (39% vs. 10%), more frequent acanthosis (32% vs. 12%), and less frequent neutrophilic infiltration (18% vs. 45%) compared to NL patients with DM 21 . These prior studies have not investigated whether different histopathologic findings correspond to differences in ulceration rates 1,21 …”

“…21 These prior studies have not investigated whether different histopathologic findings correspond to differences in ulceration rates. 1,21 As initially reported by Harvey et al, 22 our study found that 7% (6/83) of the UNL group and 0% of the NUNL group developed lesion-associated cutaneous malignancy. The prevalence of NL lesion-associated cutaneous malignancy is unknown, but our finding that all cases arose in the setting of ulcerated disease is in line with previous case reports.…”

Lower leg reconstruction after resection of a squamous cell carcinoma on necrobiosis lipoidica with a pedicled fibula and an extended anterolateral thigh flap—a case report

“…Johnson et al retrospectively reviewed 97 patients with NL, out of whom only 32% had DM. They found that histologically epidermal acanthosis was more commonly seen in diabetic patients, while naked granulomas were more frequently seen in patients without DM [ 6 ]. Our patient had no DM.…”

Treatment options for necrobiosis lipoidica: a systematic review

“…Although the diagnosis of NL is sometimes made on clinical examination alone, a biopsy may be required to distinguish NL from potential confounding diagnoses, including granuloma annulare, necrobiotic xanthogranuloma, sarcoidosis, diabetic dermopathy, and lipodermatosclerosis 2 . Histologically, NL is identified by horizontally palisaded granulomatous inflammation and necrobiosis 5 …”