Dermatology & Plastic Surgery Institute Outcomes
General Dermatology
Use of MxA Immunohistochemistry for Distinguishing Chilblain Lupus Erythematosus Skin Lesions From Idiopathic Chilblains, Perniosis
Chilblain lupus erythematosus (CHLE) is a rare form of cutaneous lupus erythematosus that presents with distinct painful lesions on acral surfaces. CHLE lesions mimic idiopathic chilblains and idiopathic perniosis lesions both clinically and histologically.¹ ² ³ ⁴ Because ≥ 18% of patients with CHLE progress to systemic lupus erythematosus (SLE)1, it is important to distinguish it from idiopathic chilblains/perniosis.
Myxovirus resistance protein A (MxA) has recently been identified to stain interferon (IFN)-induced immune cells, which are implicated in the pathogenesis of CHLE.⁵ ⁶
Thirty-one skin biopsies were identified from pathology archives, and patient charts were reviewed to confirm diagnosis of CHLE or idiopathic perniosis (IP). Paraffin-embedded sections were stained with anti-MxA antibodies (clone M143; Millipore Sigma-Aldrich; St. Louis, MO) at a 1:400 dilution; histologic patterns were objectively characterized using a standardized form.
CHLE lesion biopsies were more likely to stain as diffuse sheets of cells with intense pigmentation and to involve > 50% of dermal infiltrate. These findings were identified more frequently in the CHLE group compared with the IP group, as evidenced by the large odds ratios and P value of < 0.005.
Use of MxA Immunohistochemistry for Distinguishing Chilblain Lupus Erythematosus Skin Lesions From Idiopathic Chilblains, Perniosis
2019
| MxA staining pattern | CHLE N = 11 (%) | IP N = 20 (%) | OR | P-value |
|---|---|---|---|---|
| Trends | ||||
| Intense | 8 (73) | 1 (5) | 50.6667 | 0.0014 |
| Dermal infiltrate, >50 | 10 (91) | 4 (20) | 40 | 0.0019 |
| Distribution | ||||
| Individual cells | 8 (73) | 18 (90) | 0.2963 | 0.227 |
| Small groups, 2 - 5 cells | 10 (91) | 16 (80) | 2.5 | 0.4407 |
| Clusters, 6 - 10 cells | 9 (82) | 14 (70) | 1.9286 | 0.476 |
| Diffuse sheets, > 11 cells | 9 (82) | 3 (15) | 25.5 | 0.0012 |
| Localization | ||||
| Dermal interstitium, superficial | 9 (82) | 13 (65) | 2.4231 | 0.3316 |
| Dermal interstitium, deep | 8 (73) | 11 (55) | 2.1818 | 0.337 |
| Within dermal endothelial wall cells | 1 (9) | 8 (40) | 0.15 | 0.0972 |
| Within eccrine glands | 1 (9) | 7 (35) | 0.1857 | 0.1428 |
| Periadnexal, perieccrine | 7 (64) | 11 (55) | 1.4318 | 0.6417 |
| Periadnexal, follicular | 1 (9) | 2 (10) | 0.9 | 0.9347 |
| Perivascular, superficial | 9 (82) | 16 (80) | 1.125 | 0.9025 |
| Perivascular, deep | 10 (91) | 16 (80) | 2.5 | 0.4407 |
| Intraepidermal | 11 (100) | 18 (90) | 3.1081 | 0.4768 |
| Basement membrane zone | 0 (0) | 0 (0) | - | - |
CHLE = chilblain lupus erythematosis; IP = idiopathic perniosis; MxA = myxovirus resistance virus protein A; OR = odds ratio
CHLE and IP have been historically difficult to distinguish based on histology alone. Our results suggest that MxA staining produces a unique pattern that may help identify patients with CHLE and its systemic manifestations, and distinguish them from isolated IP.
