Lack of effect of dimethyl sulphoxide (DMSO) on amyloid deposits in lichen amyloidosis

Lack of effect of dimethylsulphoxide in cutaneous amyloidosis

OBJECTIVE

To evaluate dimethylsulphoxide (DMSO) as a topical therapeutic agent for the treatment of two major variants of primary, localized, cutaneous amyloidosis -- macular amyloidosis (MA) and papular/lichen amyloidosis (LA) -- using a monocentric, open, prospective trial.

METHODS

A total of 25 patients with histopathologically proven cutaneous amyloidosis - MA, LA and BA (biphasic amyloidosis) (13 MA, seven LA, five BA) were requested to undertake a once daily application of either 50% or 100% DMSO for 12 weeks. Progress was regularly assessed with a scoring system for pruritus, pigmentation and papules.

RESULTS

In 17 (68%) cases, the scores for pruritus decreased but never completely disappeared in any of the patients. Lightening of the pigmentation was noted in only six (24%) cases and the scores for the papules were decreased in only two out of 12 (16.6%) patients. Post-treatment skin biopsies did not reveal a reduction/disappearance of the amyloid deposits. In the follow-up period, the relapse rate was 100%.

CONCLUSION

DMSO does not have an anti-pruritic effect or amyloid-dissolving properties. As the results are partial and transient, it is concluded that DMSO is not a satisfactory treatment for cutaneous amyloidosis.

Treatment of lichen amyloidosis (LA) and disseminated superficial porokeratosis (DSP) with frequency-doubled Q-switched Nd:YAG laser

BACKGROUND

Under normal practice, the full thickness of the epidermis is peeled off when treating pigmented lesions with a frequency-doubled Nd:YAG laser. Based on this observation, it is postulated that this laser may be effective for treating lichen amyloidosis (LA) and disseminated superficial porokeratosis (DSP) for which the pathologic changes are limited to the epidermis and papillary dermis.

OBJECTIVE

To investigate the clinical effect of frequency-doubled Nd:YAG laser treatment for one patient with LA and for one patient with DSP.

METHODS

Frequency-doubled 532 nm Nd:YAG laser pulses were delivered to the lesions on the limbs of a patient with LA and the face and forearms of a patient with DSP. Lesions of LA were treated two or three times, and those of DSP were treated four times, treatment sessions being 1 month apart. For this investigation, biopsies were taken from untreated lesions prior to treatment, lesions immediately after laser treatment, and lesions present at a 9-month follow-up investigation.

RESULTS

Both the patient with LA and the patient with DSP responded well to treatment, the results of which remained unchanged at a follow-up conducted 9 months after the final treatment session.

CONCLUSION

Frequency-doubled Nd:YAG laser treatment provided excellent results for the patient with LA as for the patient with DSP. The effectiveness of this method deserves further study in a larger group of test patients.

Intermittent use of topical dimethyl sulfoxide in macular and papular amyloidosis

BACKGROUND

Severe and therapy-resistant pruritus is the most prominent feature of macular (MA) and lichen (LA) amyloidosis that leads to further amyloid deposition by recurrent frictional trauma to the epidermis. Of the various therapeutic modalities with variable success, the most encouraging and beneficial effect has been observed with topical dimethyl sulfoxide (DMSO) therapy. In a previous study, we achieved marked clinical improvement in nine of 10 patients in a daily treatment regimen over 6-20 weeks, but relapses occurred in the post-treatment follow-up period. The aims of this study are to investigate whether the patients would benefit from intermittent therapy and to determine the optimal application interval of DMSO to maintain the relief of symptoms.

METHODS

Thirteen patients with histopathologically verified cutaneous amyloidosis (five MA, two LA and six biphasic) were enrolled in the study. They were treated once daily with a 50 or 100% DMSO solution until pruritus disappeared. Then, DMSO was applied at increasing intervals until the widest effective application interval for maintenance of relief was reached. Patients were regularly followed-up by a scoring system for pruritus, papules, and pigmentation, control biopsies, photographs, blood biochemistry, and side-effects.

RESULTS

The mean time required for the disappearance of pruritus was 4.1 weeks. Remarkable flattening of the papules was achieved after an average therapy period of 9 weeks. After a total therapy period of 6.5 months, a nearly 50% remission in pigmentation and >70% flattening of papules were achieved. The widest effective DMSO application interval was 8.6 days. The side-effects of therapy were contact urticaria, desquamation, burning sensation, and garlic-like breath odor, which were more prominent with the higher concentration of DMSO. In interval therapy, side-effects were tolerated more easily than in daily therapy. No reduction of amyloid deposits was revealed in control biopsies.

CONCLUSIONS

Locally applied DMSO can break the vicious "pruritus-amyloid deposition-pruritus" cycle in patients with MA and LA. In addition to its daily use, interval therapy seems to maintain this effect and enables patients to tolerate side-effects more easily.

Cutaneous deposition diseases. Part I

The cutaneous deposition disorders are a group of unrelated conditions characterized by the presence of either endogenous or exogenous substances within the dermis or the subcutis. Part I of this two-part series will focus on metabolic processes involved in the endogenous deposition in the various forms of amyloidosis, porphyria, colloid milium, and lipoid proteinosis. We will also review the clinical, histologic, biochemical, and ultrastructural findings relevant to each disorder. Basic mechanisms of pathogenesis, diagnostic modalities, and treatment options are also discussed.

The treatment of lichen amyloidosis. A review and a new technique

BACKGROUND

A number of treatments for lichen amyloidosis have been described and the results are frequently unsatisfactory.

OBJECTIVE

To describe a new surgical technique that uses a scalpel to scrape the upper layer of the skin.

METHODS

A scalpel (No. 15) is pressed firmly and perpendicularly against the skin and scraped exactly parallel with the surface of the skin. This can be repeated until the subpapillary dermal layer.

RESULTS

Scraping with the scalpel removes the epidermis and deposits of amyloid in the dermis. All nine patients healed without complications with acceptable to good aesthetic results.

CONCLUSION

The technique is quick, effective, simple to perform, inexpensive, and safe. This is another option in the surgical treatment of selected cases of lichen amyloidosis.

Lichen amyloidosus: a consequence of scratching

BACKGROUND

Lichen amyloidosus (LA) is generally said to be a pruritic type of amyloidosis of unknown cause. Histopathologically, it is characterized by epidermal changes of lichen simplex chronicus and by deposits of amyloid in the papillary dermis that are derived from keratin peptides of necrotic keratinocytes. Chronic scratching is responsible for the development of lichen simplex chronicus and may lead to necrosis of individual keratinocytes.

OBJECTIVE

Our purpose was to evaluate whether chronic scratching may also be responsible for the formation of amyloid in LA.

METHODS

We studied patients with LA in regard to histopathologic findings, onset of pruritus, associated diseases, and response to treatment.

RESULTS

In most cases, pruritus had preceded the skin lesions. Eight of nine patients suffered from diseases other than LA that may be associated with pruritus. Histopathologically, amyloid was confined to areas that also showed signs of lichen simplex chronicus. Systemic treatment with sedating antihistamines and intense local treatment with corticosteroids were found to be effective.

CONCLUSION

LA is considered to be a variant of lichen simplex chronicus in which scratching leads to necrosis of keratinocytes and eventually to the formation of amyloid in the papillary dermis. Because chronic scratching seems to be the cause and not the result of the deposits of amyloid, treatment should be directed at the amelioration of pruritus.

Extensive lichen amyloidosus refractory to DMSO

While lichen amyloidosus reportedly may respond to dimethyl sulfoxide (DMSO) application, we present a patient whose lesions were refractory to this agent. This Japanese woman had chronic extensive lichen amyloidosus, mainly on her trunk. Her 10-year history of using nylon towels was the suspected cause. The application of DMSO ointment had no clinical effect, and the amyloid deposits persisted in the histological specimens despite the treatment. The administration of a topical corticosteroid led to gradual clinical improvement.