|Year : 1997 | Volume
| Issue : 2 | Page : 105-106
Primary cutaneous amyloidosis
Bela Padhiar, Umesh Karia, Bel Shah
Source of Support: None, Conflict of Interest: None
Three cases of primary cutaneous amyloidosis are reported. Family history was negative. Systemic involvement was ruled out. Histopathology was confirmed by congored stain. Patients responded to oral colchicine.
Keywords: Primary cutaneous amyloidosis
|How to cite this article:|
Padhiar B, Karia U, Shah B. Primary cutaneous amyloidosis. Indian J Dermatol Venereol Leprol 1997;63:105-6
| Introduction|| |
Amyloid is a proteinaceous substance that is deposited in the skin and tissues. Amyloid has certain characteristic physicochemical properties like congophilia and green birefringence under polarized light.
In primary localized cutaneous amyloidosis, deposition of amyloid occurs in previously apparently normal skin with no evidence of deposits occurring in internal organs. The aetiology is unknown.
Primary cutaneous amyloidosis usually presents in early adult life and persists for many years; both sexes are equally affected.
The lesions of mucular and maculopapular amyloidosis are usually confined to the extensor aspect of extremities, back or chest. Mild to moderate pruritus is predominant symptom, but pruritus may be absent in 18% of cases. The predominant sign is clusters of small pigmented macules about 2 or 3 mm in diameter which may coalesce to produce macular hyperpigmented areas. A reticulate or 'rippled' pattern of pigmentation may occur. Sometimes, hypopigmented areas may also occur.
The treatment of primary cutaneous amyloidosis is disappointing. Milder cases may respond to potent topical corticosteroids or topical 10% dimethylsulphoxide (DMSO). Etretinate and long term cyclophosphamide and clochicine may be helpful in decreasing the troublesome pruritus.
| Case Report|| |
Case 1. A 24-year-old female presented with itchy, hyperpigmented lesions on both forearms, upper arms, legs and upper back since 4-5 years. On examination, clusters of hyperpigmented macules were seen on both forearms, upper arms, legs and upper back. Coalesced macules gave rise to reticulate pattern on extensor surface of forearms and legs.
Case 2. A 28-year-old male presented with asymptomatic hyperpigmented lesions on upper chest and upper back since 1 year. On examination, reticular hyperpigmented macules were seen on upper chest and upper back. 10% KOH smear was negative.
Case 3. A 40-year-old female presented with severely itchy, hyperpigmented lesions on both legs, upper chest and upper back since 18-20 years. On examination, reticular hyperpigmented macules were seen on both legs, upper chest and upper back.
Clinically macular amyloidosis, [2, 3] should be differentiated from postinflammatory hyperpigmentation, resolving lichen planus or neurodermatitis. Reticulate hyperpigmentation may be seen in reticular erythematous mucinosis and in atopic eczema (dirty neck). Here, in these 3 cases, family history was negative and there was no systemic involvement. Biopsy was taken and special stain congo red was done.
On histopathological examination, in macular amyloidosis, the deposits of amyloid are smaller and in small faceted clumps in the papillary dermis. The epidermis is usually of normal thickness, but pigmentary incontinence with melanophages may occur.
In case 2 alcian blue stain was performed which did not reveal any mucin deposits.
Oral antihistaminics and topical potent steroid were given to both females, while male (Case 2) was advised to apply only topical potent steroid. Oral colchicine was given to all three patients. After 1 month, pigmentation and itching was decreased and almost disappeared after 3-4 months of therapy.
| Discussion|| |
The diagnosis of primary cutaneous amyloidosis was made on the basis of characteristic clinical features. It was further confirmed by histology and special staining reaction.
All the 3 patients responded to oral colchicine therapy as pigmentation and itching started regressing after 1 month and almost disappeared after 3-4 months of therapy.
| References|| |
|1.||Black MM. Primary localized amyloidosis of the skin: clinical variants, histochemistry and ultrastructure. In: Wegelius O, Pasternack A, eds. Amyloidosis. London: Academic Press, 1976:479-513. |
|2.||Black MM, Wilson Jones E. Macular amyloidosis. Br J Dermatol 1971;84:199-209. |
|3.||Brownstein MH, Hashimoto K, Greenwalg G. Biphasic amyloidosis: link between macular and lichenoid forms. Br J Dermatol 1973;88:25-9. |
|4.||Colver GB, Mortimer PS, Millard PR, et al. The 'dirty neck' reticulate pigmentation in atopics. Clin Exp Dermatol 1987;12:1-4. [PUBMED] |