11 Amyloidosis William Y-M Tang and Loi-yuen Chan Evidence Levels: A Double-blind study B Clinical trial ≥ 20 subjects C Clinical trial < 20 subjects D Series ≥ 5 subjects E Anecdotal case reports Amyloid is an altered, insoluble protein that can accumulate in one or many organs, causing dysfunction. Primary localized cutaneous amyloidosis is characterized by the deposition of amyloid in the skin without involving any internal organ. It occurs more commonly in Southeast Asian, Chinese, Middle Eastern, and South American people. There are three clinical forms: lichen, macular, and nodular. The co-occurrence of macular and lichen amyloidosis in a patient is known as biphasic amyloidosis. The amyloid in macular and lichen amyloidosis is derived from degenerated keratinocytes, whereas in nodular amyloidosis it is derived from immunoglobulin light chains from a local plasma cell clone. Lichen amyloidosis (see Figure) is a persistent eruption of multiple red-brown hyperkeratotic papules often affecting extensor aspects of extremities, especially the pretibial surfaces. It appears more commonly in males. Apart from its cosmetic nuisance, marked itching can occur. Although familial cases of lichen amyloidosis have been reported, most cases occur as isolated events having no association with systemic disease. Macular amyloidosis is characterized by an eruption consisting of small, dusky-brown or grayish pigmented macules distributed symmetrically over the upper back and upper arm. It has a reticulated or rippled pattern. Itch is variable, and patients often seek medical advice for aesthetic issues and pruritus. Nodular amyloidosis is the rarest subtype. It is characterized by single or multiple waxy, firm, brown or pink nodules involving the legs, head, trunk, arms, and genitalia. It is usually asymptomatic. Management strategy Lesions of localized cutaneous amyloidosis can produce considerable pruritus. Patients seek treatment to alleviate pruritus and the undesirable appearance. Currently there are no accepted standard treatments for the various types of cutaneous amyloidosis because of a lack of good clinical trials. As pruritus is a common symptom, antihistamines and topical corticosteroids are prescribed as first-line treatments. Phototherapy (UVB or PUVA) has been used to treat lichen amyloidosis successfully for relief of pruritus. Acitretin may be added for combined therapy. Laser treatments reported to be successful in treating cutaneous amyloidosis include carbon dioxide, pulsed-dye (PDL) and neodymium:yttrium aluminum garnet (Nd:YAG). Dermabrasion has been successful in treating lichen and nodular amyloidosis. This improves cosmesis and alleviates pruritus, but brings accompanying procedural pain and the development of skin atrophy. There is an anecdotal report that dermabrasion of lichen amyloidosis under tumescent anesthesia can result in remarkable pain reduction even though the total amount of local anesthetic required is low. Other treatment choices include tacrolimus, transcutaneous electrical nerve stimulation (TENS) and tocoretinate. Topical dimethylsulfoxide (DMSO) also has been reported to benefit lichen and macular amyloidosis. However, a more recent study on 25 patients reported lack of efficacy. Specific investigations Skin biopsy All forms of amyloidosis have similar histological findings. On light microscopy, amyloid is characteristically a pink, amorphous material. Special stains, such as Congo red and crystal violet, can highlight the amyloid deposit. Amyloid can be metachromatically stained red by crystal violet staining of an aqueous mount of the specimen. Congo red staining of amyloid shows apple-green birefringence under polarized light microscopy. First-Line therapies Sedating antihistamines E Topical high-potency corticosteroids E Only gold members can continue reading. Log In or Register to continue Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window) Related Related posts: Discoid lupus erythematosus Mucoceles Tinea capitis Herpes genitalis Necrolytic migratory erythema Nevoid basal cell carcinoma syndrome Stay updated, free articles. Join our Telegram channel Join Tags: Treatment of Skin Disease Comprehensive Therapeutic Strategies Aug 7, 2016 | Posted by admin in Dermatology | Comments Off on Amyloidosis Full access? Get Clinical Tree
11 Amyloidosis William Y-M Tang and Loi-yuen Chan Evidence Levels: A Double-blind study B Clinical trial ≥ 20 subjects C Clinical trial < 20 subjects D Series ≥ 5 subjects E Anecdotal case reports Amyloid is an altered, insoluble protein that can accumulate in one or many organs, causing dysfunction. Primary localized cutaneous amyloidosis is characterized by the deposition of amyloid in the skin without involving any internal organ. It occurs more commonly in Southeast Asian, Chinese, Middle Eastern, and South American people. There are three clinical forms: lichen, macular, and nodular. The co-occurrence of macular and lichen amyloidosis in a patient is known as biphasic amyloidosis. The amyloid in macular and lichen amyloidosis is derived from degenerated keratinocytes, whereas in nodular amyloidosis it is derived from immunoglobulin light chains from a local plasma cell clone. Lichen amyloidosis (see Figure) is a persistent eruption of multiple red-brown hyperkeratotic papules often affecting extensor aspects of extremities, especially the pretibial surfaces. It appears more commonly in males. Apart from its cosmetic nuisance, marked itching can occur. Although familial cases of lichen amyloidosis have been reported, most cases occur as isolated events having no association with systemic disease. Macular amyloidosis is characterized by an eruption consisting of small, dusky-brown or grayish pigmented macules distributed symmetrically over the upper back and upper arm. It has a reticulated or rippled pattern. Itch is variable, and patients often seek medical advice for aesthetic issues and pruritus. Nodular amyloidosis is the rarest subtype. It is characterized by single or multiple waxy, firm, brown or pink nodules involving the legs, head, trunk, arms, and genitalia. It is usually asymptomatic. Management strategy Lesions of localized cutaneous amyloidosis can produce considerable pruritus. Patients seek treatment to alleviate pruritus and the undesirable appearance. Currently there are no accepted standard treatments for the various types of cutaneous amyloidosis because of a lack of good clinical trials. As pruritus is a common symptom, antihistamines and topical corticosteroids are prescribed as first-line treatments. Phototherapy (UVB or PUVA) has been used to treat lichen amyloidosis successfully for relief of pruritus. Acitretin may be added for combined therapy. Laser treatments reported to be successful in treating cutaneous amyloidosis include carbon dioxide, pulsed-dye (PDL) and neodymium:yttrium aluminum garnet (Nd:YAG). Dermabrasion has been successful in treating lichen and nodular amyloidosis. This improves cosmesis and alleviates pruritus, but brings accompanying procedural pain and the development of skin atrophy. There is an anecdotal report that dermabrasion of lichen amyloidosis under tumescent anesthesia can result in remarkable pain reduction even though the total amount of local anesthetic required is low. Other treatment choices include tacrolimus, transcutaneous electrical nerve stimulation (TENS) and tocoretinate. Topical dimethylsulfoxide (DMSO) also has been reported to benefit lichen and macular amyloidosis. However, a more recent study on 25 patients reported lack of efficacy. Specific investigations Skin biopsy All forms of amyloidosis have similar histological findings. On light microscopy, amyloid is characteristically a pink, amorphous material. Special stains, such as Congo red and crystal violet, can highlight the amyloid deposit. Amyloid can be metachromatically stained red by crystal violet staining of an aqueous mount of the specimen. Congo red staining of amyloid shows apple-green birefringence under polarized light microscopy. First-Line therapies Sedating antihistamines E Topical high-potency corticosteroids E Only gold members can continue reading. Log In or Register to continue Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window) Related Related posts: Discoid lupus erythematosus Mucoceles Tinea capitis Herpes genitalis Necrolytic migratory erythema Nevoid basal cell carcinoma syndrome Stay updated, free articles. Join our Telegram channel Join Tags: Treatment of Skin Disease Comprehensive Therapeutic Strategies Aug 7, 2016 | Posted by admin in Dermatology | Comments Off on Amyloidosis Full access? Get Clinical Tree
Sedating antihistamines
Topical high-potency corticosteroids
