Cutaneous mucinoses: an overview Aefan ul Bari

Review Article Cutaneous mucinoses: an overview

Arfan ul Bari PAF Hospital Sargodha

Abstract The cutaneous mucinoses are a group of connective tissue disorders characterized by the deposition of mucin, either focally or diffusely, in the interstices of the dermis. The diseases may occur as a primary (metabolic) event or as a secondary (catabolic) process in certain dermatoses such as lupus erythematosus and dermatomyositis. Systemic abnormalities are seen with most of these disorders. A brief review and classification of the disorders included in this group is given here.

Key words Cutaneous mucinoses, dermal mucinoses, mucin, connective tissue disorders.

The cutaneous mucinoses are a which may be either dermal or follicular, heterogeneous group of diseases so named and into neoplastic-hamartomatous because of the variable amount of mucin mucinoses. Histopathologic diagnosis is accumulation in the skin or within the hair particularly difficult for dermal mucinoses follicle. Mucin is jelly-like acid and requires clinicopathologic correlation. mucopolysacharide (glycosaminoglycan) of Three histologic clues, namely the pattern of the ground substances and probably plays a mucin distribution (diffuse or focal), the role in extravascular exchange of level of mucin deposit in the dermis and metabolites. It is produced by fibroblasts some additional findings may help and is composed of hyaluronic acid bound to diagnosis. Follicular mucinoses have the heparin and chondroitin sulphate.1,2 We easiest pattern to recognize histologically. divide the cutaneous mucinoses into two Neoplastic-hamartomatous cutaneous groups: the distinctive cutaneous mucinoses mucinoses include mucinous nevus, a in which the mucin deposit is a distinctive benign hamartoma, and myxoma, which is a histopathologic feature that manifests as a benign tumor to be differentiated from clinically specific lesion (also called the reactive cutaneous focal .1-4 metabolic or primary group), and the Histologically, mucins are stained with diseases associated with histopathologic alcian blue at pH 2.5 (blue),mucicarmine mucin deposition as an additional finding (red), colloidal iron (blue green) and the (also called the catabolic or secondary colouration depends on the number and group). The former are further divided into nature of the acid groups. They are also degenerative-inflammatory mucinoses, stained metachromatically with toluidine blue, methyline blue and thionine.5,6 Periodic Address for Correspondence Squadron Leader Dr. Arfan ul Bari acid-schiff (PAS) stains heparin but not Consultant Dermatologist, PAF Hospital, hyaluronic acid. On the basis of histological Sargodha site and pattern of mucin deposition and Ph (off) # 0451-5553307 extent of involvement, cutaneous mucinoses Ph (res) # 0451-5553308 Email: [email protected] may also be divided into focal, follicular and

244 Journal of Pakistan Association of Dermatologists 2004; 14: 244-247.

diffuse. Focal mucinoses are localized • Self-healing juvenile cutaneous benign forms that are usually not associated mucinosis with other organ involvement. Follicular • Cutaneous mucinosis of infancy mucinosis is generally considered with • Papular and nodular mucinosis cutaneous lymphomas. Diffuse cutaneous associated with lupus erythematosus mucinoses differ from local mucinoses by (tumid LE) greater cutaneous involvement, systemic- • of the toxic oil organ dysfunction from mucin deposition syndrome and associated extra-cutaneous disease not (ii) Focal related to mucin deposition. The full Focal mucinoses are localized benign forms description of clinicopathological and and generally, are not associated with other diagnostic features in case of individual organ involvement disorders is beyond the scope of this article, • Acral persistent papular mucinosis therefore, only the major mucinoses are • Cutaneous focal mucinosis listed and classified below and only • Oral focal mucinosis treatment aspect has been touched briefly in • Digital mucous cyst the end. • Mucocele • Cutaneous myxoma Clinicopathological classification 3,4,7-10 • Nevus mucinosis (Hunter syndrome) A. Primary (metabolic) mucinoses (iii) Follicular forms These include cutaneous mucinoses in These are characterized clinically by which the mucin deposit is a distinctive infiltrated scaly plaques with loss of hair and histopathologic feature that manifests as a histologically by mucin deposition in clinically specific lesion and occurring as a sebaceous glands and the outer root sheath primary pathology. This group is further of hair follicles. The cases may or may not divided into diffuse, focal and follicular on be associated with lymphomas. the basis of histological pattern and extent of • (follicular involvement. mucinosis) (i) Diffuse These generally comprise of disorders with diffuse cutaneous • Urticaria-like follicular mucinosis involvement associated with variable systemic organ involvement such as B. Secondary (catabolic) mucinoses endocrine system. This group includes the diseases in which • Generalized myxedema dermal mucinosis may, to a greater or lesser extent, be associated with otherwise typical • Pretibial myxedema histopathological features of that disease. • Reticular erythematous mucinosis • Lupus erythematosus • Scleredema • Dermatomyositis • Scleromyxedema • • Diffuse papular mucinosis • Jessner's lymphocytic infiltrate • Lichen myxedematosus

245 Cutaneous mucinoses: an overview Aefan ul Bari

• Degos disease (malignant atrophic Conclusion papulosis) • Hereditary progressive mucinous The cutaneous mucinoses are a complex histiocytosis group of dermatologic diseases with local, • Papular mucinosis in L-tryptophan- follicular, or diffuse disease. The diffuse induced eosinophilia-myalgia cutaneous mucinoses are remarkable not syndrome only for their dermal disease, but also for the • Mucinosis accompanying numerous systemic manifestations. Because mesenchymal and neural tumours of the variability of associated systemic • Mucopolysaccharidoses manifestations, some with substantial morbidity and mortality, it is important for Treatment 11-16 the clinical dermatologist to be able accurately to diagnose and differentiate Treatment of most of the cutaneous various diffuse cutaneous mucinoses. mucinoses remains unsatisfactory and no uniformly effective therapy exists, although References several treatments are routinely used. 1. Truhan AP, Roenigk HH Jr. The Topical therapy is generally of no benefit. cutaneous mucinoses. J Am Acad There have been occasional reports of Dermatol 1986; 14 : 1-18. 2. Rongioletti F, Rebora A. Cutaneous spontaneous resolution of localized lesions. mucinoses. Ann Dermatol Venereol Clearance of lesions has been reported with 1993; 120 : 75-87. melphalan and cyclophosphamide alone or 3. Jackson EM, English JC 3rd. Diffuse cutaneous mucinoses. Dermatol Clin. in combination with prednisone. Both 2002; 20 : 493-501 isotretinoin and etretinate have been 4. Stephens CJM, McKee PH, Black MM. associated with improvement. Interferon- The dermal mucinoses. Adv Dermatol alpha, cyclosporine, PUVA 1993; 8: 201-27. 5. Rongioletti F, Rebora A. The new photochemotherapy, electron-beam therapy, cutaneous mucinoses: A review with an IVIg, and dermabrasion have also been up-to-date classification of cutaneous attempted with variable succes. Isolated mucinoses. J Am Acad Dermatol 1991; 24 : 265-70. cases document the beneficial responses of 6. Scott JE, Dorling J. Differential staining dapsone, indomethacin, and interferons. of acid glycosaminoglycans by alcian Pulsed dye laser has been found successful blue in salt solutions. Histochemie 1965; 5: 221-3. in treating reticular erythematous mucinosis 7. Rongioletti F, Rebora A. Cutaneous in one report. The overall prognosis for mucinoses: microscopic criteria for extensive disease is poor. Because of the diagnosis. Am J Dermatopathol 2001; 23 : 257-67. variable course of the disease and the 8. Jeremy E R. Papular mucinosis. likelihood of spontaneous resolution, Dermatology Online Journal 2001; 7 : therapeutic efficacy is difficult to prove. 13. 9. Clark BJ, Mowat A, Fallowfield ME, Lee FD. Papular mucinosis. Papular mucinosis: is the inflammatory cell infiltrate neoplastic? The presence of monotypic plasma cell population

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demonstrated by in situ hybridization. cyclophosphamide therapy. Arch Br J Dermatol 1996; 135 : 467-70. Dermatol 1975; 111 : 1325-30. 10. Bata-Csorgo Z, Husz S, Foldes M, 14. Tschen JA, Chang JR. Korom I, Molnar K, Morvay M, et al. Scleromyxedema: treatment with Scleromyxedema. J Am Acad Dermatol interferon alpha. J Am Acad Dermatol 1999; 41 : 343-6. 1999; 40 : 303-6. 11. Sperber BR, Allee J, James WD. Self- 15. Liiter RK. Scleromyxedema: response healing papular mucinosis in an adult . J to high-dose intravenous Am Acad Dermatol. 2004; 50 : 121-3. immunoglobulin (hdIVIg). J Am Acad 12. Caputo R, Grimalt R, Gelmetti C. Self- Dermatol 2000; 43 : 403-6. healing juvenile cutaneous mucinosis. 16. Greve B, Raulin C. Treating REM Arch Dermatol 1995; 131 : 459-61. syndrome with the pulsed dye laser. 13. Howden SM, Herndon JH Jr, Freeman Lasers Surg Med 2001; 29 : 248-51. RG. Lichen myxedematosus: a dermal infiltrate disorder responsive to

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