FIGURATE ERYTHEMA ENCOMPASSING BENIGN CUTANEOUS OUTGROWTHS

A 47 year old male presented to Dermatology OPD with complaints of red colored lesions, gradually increasing in size, associated with moderate itching  all over the body for the past 3 weeks. He occasionally took Tab. Hydroxyzine 10mg over the counter for itching and gives a negative history for topical application before or after onset of the rash. He has no known comorbidities and there was no history of intake of other drugs. Dermatological examination showed numerous well defined eyrthematous annular patches of sizes varying from 1*1cm to 5*4cm  with trailing scale at the borders. These patches were confined only to pedunculated or flat outgrowths over the skin (soft fibroma/ acrochordon and seborrheic keratosis), distributed over trunk,  abdomen, axilla and thighs. Considering the morphology, a differential diagnosis of Erythema Annulare Centrifugum, Meyerson phenomenon, Granuloma Annulare and contact dermatitis were made. The blood investigations including fasting and post prandial blood sugar, HbA1C, lipid profile, complete blood count, absolute eosinophil count, ESR , CRP,  renal and liver function test, chest X ray were taken and found to be normal. A 4mm punch biopsy was taken from the periphery of the patch. Histopathological examination showed spongiosis, dermal edema, diffuse lymphohistiocytic inflitrate over papillary dermis and coat sleeve pattern of perivascular infiltrate. Alcian blue stain was negative for dermal mucin. Thus, a diagnosis of Erythema Annulare Centrifugum was made.

 Acrochordon and seborrheic keratosis were excised by Radio frequency ablation. A short course of topical mid potent steroid with antibiotic combination and oral antihistamines were prescribed for 2 weeks. The patient was followed up at week 2, the lesions were resolving with post inflammatory hyperpigmentation. There was reduction in scaling and erythema. At week 5, the lesions were completely resolved, only minimal post inflammatory hyperpigmentation was noted. He was further followed up for a period of 3 months and no recurrence was observed.

 

Figure 1: Clinical picture of Erythema Annulare Centrifugum surrounding seborrheic keratosis and acrochordon. Note the trailing scale just behind the advancing edge of the patch.

Figure 2: Histopathology showing spongiosis, dermal edema and coat sleeve pattern of perivascular lymphohistiocytic infiltrate.

Figure 3: Clinical picture at week 2 following radiofrequency ablation of seborrheic keratosis and acrochordons. Note that the erythema and scaling are significantly reduced, post inflammatory hyperpigmentation is noted.

Figure 4: Clinical picture at week 5, post inflammatory hyperpigmentation is also reduced significantly.

 

Soft fibromas are benign cutaneous outgrowths, commonly called skin tag, arising from connective tissue (fibroblasts) of dermis. The other names include acrochordon or fibroepithelial polyp. They occur as skin colored or pigmented pedunculated papules with affinity to flexures like neck, axillae, groin and eyelids. They are mostly asymptomatic and start in late adolescent or early adult life. The association includes genetics, obesity and dyslipidemia, diabetes mellitus and metabolic syndrome.[1,2]  Excision is suggested either for cosmetic reasons or repeated friction with the garments which could possibly cause irritation.

 

Seborrheic keratosis is also a benign tumor arising from the proliferation of  immature epidermal keratinocytes.[3,4] They are asymptomatic or occasionally presents with itching, commonly occuring in individuals > 50 years. They present as few well defined pigmented papules or plaques giving "stuck on" appearance, sometimes pedunculated. Concern should arise when there is rapid progression or multiple lesions as in Lesser trelat sign, where an underlying gastrointestinal malignancy should be suspected.  Removal is warranted if it is symptomatic or  cosmetically distressing to the individual. Biopsy may be required to rule out cutaneous malignancy if the morphology is atypical.

 

These benign outgrowths of the skin rarely exhibit reaction pattern viz, Meyerson phenomenon, Halo phenomenon and even more rarely Erythema Annulare Centrifugum.

 

Erythema Annulare Centrifugum is one of the figurate erythema characterised by annular erythematous patches/ plaques with trailing scale at the periphery (fine annular scaling that trails behind the border), progressing centrifugally at the rate of 1 to 3 mm per day.[5] It is a hypersensitivity reaction that results in release of inflammatory cytokines and vasoactive peptides which is attributed to the peripheral spreading.  It usually affects adults and rare in newborn or children. Etiology includes drugs (penicillin, salicylates/NSAIDS, antimalarials, rituximab, amitryptiline, interferons, ribavirin), fungal infections ( Candidiasis and Dermatophytosis),  viral infections (Chicken pox, EBV, HIV), bacterial infections (Pseudomonas), parasitic infections (Phthirus pubis), autoimmune endocrinopathies, pregnancy, Crohn's disease, malignancy (leukemia and lymphoma ) where it is called PEACE ( Paraneoplastic Erythema Annulare Centrifugum Eruption). [6]

 

EAC can take superficial or deep forms. The superficial variant has predominant surface changes like trailing scale. However, the deep gyrate variant presents as palpable erythema with central clearing and devoid of surface changes. Very rarely, telengiectasia or purpura may be seen.

 

Histopathology is often mandatory to differentiate EAC from other annular erythema viz, Erythema gyratum repens, Erythema multiforme, Erythema chronicum migrans, subcutaneous lupus erythematosus,  Granuloma Annulare, Dermatophytosis etc. In superficial EAC , there is predominant epidermal changes like Hyperkeratosis, parakeratosis and spongiosis. Vacuolar degeneration may be present in some cases. Coat sleeve pattern of perivascular infiltrate is seen. Eosinophils may also be seen in perivascular infiltrate. The advancing edge may show dermal edema.  In deep EAC, epidermal changes are not seen, however, there are dense perivascular lymphohistiocytic infiltrate in the papillary and reticular dermis.[7]

 

With respect to treatment, the primary cause should be investigated and eliminated. It is usually self resolving in about 6-8 weeks. Topical therapy includes potent/ midpotent corticosteroids, tacrolimus. In resistant cases, systemic corticosteroids or immunomodulators like methotrexate, mycophenolate mofetil, hydroxychloroquine etc can be added. Some authors suggests the use of antibiotics- erthromycin, Azithromycin, doxycycline or  metronidazole if infection is suspected. [8,9] In resistant cases, Apremilast, Roflumilast, upadacitinib or etanercept can be tried. [10,11,12]

 

 

1) Farag AGA, Abdu Allah AMK, El-Rebey HS, Mohamed Ibraheem KI, Mohamed ASED, Labeeb AZ, Elgazzar AE, Haggag MM. Role of insulin-like growth factor-1 in skin tags: a clinical, genetic and immunohistochemical study in a sample of Egyptian patients. Clin Cosmet Investig Dermatol. 2019;12:255-266.

2) Kochet K, Lytus I, Svistunov I, Sulaieva O. [SKIN PATHOLOGY IN DIABETES MELLITUS: CLINICAL AND PATHOPHYSIOLOGICAL CORRELATIONS (REVIEW)]. Georgian Med News. 2017 Dec;(273):41-46.

3) Barthelmann S, Butsch F, Lang BM, Stege H, Großmann B, Schepler H, Grabbe S. Seborrheic keratosis. J Dtsch Dermatol Ges. 2023 Mar;21(3):265-277.

4) Sun MD, Halpern AC. Advances in the Etiology, Detection, and Clinical Management of Seborrheic Keratoses. Dermatology. 2022;238(2):205-217

5) Mshrai H, Fallatah B, Alwafi D, Babkoor D, Sufyani HA, Hawsawi KA. Erythema annulare centrifugum (EAC): a case report of annually recurring EAC. J Health Sci. 2016;6(5):74-6.

6) Chodkiewicz H, Cohen P. Paraneoplastic Erythema Annulare Centrifugum Eruption: PEACE. Am J Clin Dermatol. 2012;13(4):239-46.

7)Kim D, Lee J, Lee J, Park Y. Erythema annulare centrifugum: analysis of associated diseases and clinical outcomes according to histopathologic classification. Ann Dermatol. 2016;28(2)

8) Fidanzi C, Bevilacqua M, Salvia G, Romanelli M, Dini V, Janowska A. Idiopathic erythema annulare centrifugum successfully treated with doxycycline: A viable therapeutic option? Skin Res Technol. 2023 Oct;29(10):e13477

9) De Aloe G, Rubegni P, Risulo M, Sbano P, Poggiali S, Fimiani M. Erythema annulare centrifugum successfully treated with metronidazole. Clin Exp Dermatol. 2005 Sep;30(5):583-4.

10) Lee MS, Klebanov N, Yanes D, Stavert R. Refractory erythema annulare centrifugum treated with apremilast. JAAD Case Rep. 2021 Sep;15:100-103

11) Calderon P, Ajmal H, Brady M, Kartono F. Refractory erythema annulare centrifugum treated with roflumilast. JAAD Case Rep. 2024 May;47:17-19

12) Foy V, McCusker MM, Payette MJ. A case of erythema annulare centrifugum cleared with upadacitinib. JAAD Case Rep. 2023 Dec;42:20-22.