The mechanism of oxidative stress in keloid fibroblasts and the experimental study of early application of angiotensin-converting enzyme inhibitor.

Objective To investigate the protective effects of an angiotensin-converting enzyme inhibitor after inducing oxidative stress on keloid fibroblasts. Methods Primary keloid fibroblasts were isolated and cultured by enzyme digestion combined with the tissue adhesion method in vitro, and the third to fifth generations of cells were selected for the experiment. For 24 hours, keloid fibroblasts were treated with different concentrations of hydrogen peroxide. Different concentrations of angiotensin-converting enzyme inhibitor were added to the keloid fibroblast culture medium, and then the cells were treated with hydrogen peroxide for 24 hours. Results With the increase of hydrogen peroxide concentration, the growth of keloid fibroblasts was inhibited and the levels of malondialdehyde, superoxide dismutase, and reactive oxygen species increased gradually, accompanied by an increase in the expression of nicotinamide adenine dinucleotide phosphate oxidase and collagen I mRNA. The expression of nicotinamide adenine dinucleotide phosphate oxidase-mRNA in keloid fibroblasts and the formation of reactive oxygen species in keloid fibroblasts were induced by different concentrations of angiotensin II, and the most significant effect was at 10-5 mmol/mL. The effects of diphenyleneiodonium chloride (NOX inhibitor), N-acetylcysteine (reactive oxygen species inhibitor) and nicotinamide adenine dinucleotide phosphate oxidase (NADPH oxidase) RNA treatment on angiotensin II-induced nicotinamide adenine dinucleotide phosphate oxidase and collagen I increased significantly. Hydrogen peroxide and angiotensin II alone or combined can induce NADPH oxidase and reactive oxygen species expression in keloid fibroblasts. When the angiotensin-converting enzyme inhibitor was added, the expression of NADPH oxidase and reactive oxygen species in keloid induced by hydrogen peroxide and angiotensin II could be inhibited. Conclusion Oxidative stress can lead to increased expression of reactive oxygen species, NADPH oxidase and collagen I in keloid fibroblasts, suggesting oxidative stress mediates the migration of human keloid fibroblasts and extracellular matrix synthesis.

Skin fibrosis associated with keloid, scleroderma and Jorge Lobo's disease (lacaziosis): An immuno-histochemical study.

Fibrosis is a common pathophysiological response of many tissues and organs subjected to chronic injury. Despite the diverse aetiology of keloid, lacaziosis and localized scleroderma, the process of fibrosis is present in the pathogenesis of all of these three entities beyond other individual clinical and histological distinct characteristics. Fibrosis was studied in 20 samples each of these three chronic cutaneous inflammatory diseases. An immunohistochemical study was carried out to explore the presence of α-smooth muscle actin (α-SMA) and vimentin cytoskeleton antigens, CD31, CD34, Ki67, p16; CD105, CD163, CD206 and FOXP3 antigens; and the central fibrotic cytokine TGF-ß. Higher expression of vimentin in comparison to α-SMA in all three lesion types was found. CD31- and CD34-positive blood vessel endothelial cells were observed throughout the reticular dermis. Ki67 expression was low and almost absent in scleroderma. p16-positive levels were higher than ki67 and observed in reticular dermis of keloidal collagen in keloids, in collagen bundles in scleroderma and in the external layers of the granulomas in lacaziosis. The presence of α-actin positive cells and rarely CD34 positive cells, observed primarily in keloids, may be related to higher p16 antigen expression, a measure of cell senescence. Low FOXP3 expression was observed in all lesion types. CD105-positive cells were mainly found in perivascular tissue in close contact with the adventitia in keloids and scleroderma, while, in lacaziosis, these cells were chiefly observed in conjunction with collagen deposition in the external granuloma layer. We did not find high involvement of CD163 or CD206-positive cells in the fibrotic process. TGF-ß was notable only in keloid and lacaziosis lesions. In conclusion, we have suggested vimentin to be the main myofibroblast general marker of the fibrotic process in all three studied diseases, while endothelial-to-mesenchymal transition (EndoMT) and mesenchymal stem cells (MSCs) and M2 macrophages may not play an important role.

Histoid leprosy presenting as a large tumor

Abstract Histoid leprosy is a rare form of multibacillary leprosy, characterized by the presence of papules, plaques, or nodules whose appearance is keloid-like, skin colored, or erythematous. Fusiform cells are the main histopathological feature. Due to the fact that it can simulate other dermatological lesions, for example, dermatofibroma and neurofibroma, it constitutes a diagnostic challenge for clinicians and pathologists. It is a bacilliferous form of leprosy, and it plays an important role in disease transmission. A case of a patient with histoid leprosy living in the Northeast Region of Brazil is reported.

Lobomycosis: exuberant presentation with malignant transformation

Abstract Lobomycosis is a chronic granulomatous infection caused by the yeast Lacazia loboi, typically found in tropical and subtropical geographical areas. Transmission occurs through traumatic inoculation into the skin, especially in exposed areas, of men who work in contact with the soil. Lesions are restricted to the skin and subcutaneous tissue, with a keloid-like appearance in most cases. The occurrence of squamous cell carcinoma on skin lesions with a long evolution is well known; however, there are scarce reports of lobomycosis that developed into squamous cell carcinoma. The authors report a patient from the Brazilian Amazon region, with lobomycosis and carcinomatous degeneration, with an unfavorable outcome, due to late diagnosis.

Lobomycosis: exuberant presentation with malignant transformation.

Lobomycosis is a chronic granulomatous infection caused by the yeast Lacazia loboi, typically found in tropical and subtropical geographical areas. Transmission occurs through traumatic inoculation into the skin, especially in exposed areas, of men who work in contact with the soil. Lesions are restricted to the skin and subcutaneous tissue, with a keloid-like appearance in most cases. The occurrence of squamous cell carcinoma on skin lesions with a long evolution is well known; however, there are scarce reports of lobomycosis that developed into squamous cell carcinoma. The authors report a patient from the Brazilian Amazon region, with lobomycosis and carcinomatous degeneration, with an unfavorable outcome, due to late diagnosis.

Histoid leprosy presenting as a large tumor.

Histoid leprosy is a rare form of multibacillary leprosy, characterized by the presence of papules, plaques, or nodules whose appearance is keloid-like, skin colored, or erythematous. Fusiform cells are the main histopathological feature. Due to the fact that it can simulate other dermatological lesions, for example, dermatofibroma and neurofibroma, it constitutes a diagnostic challenge for clinicians and pathologists. It is a bacilliferous form of leprosy, and it plays an important role in disease transmission. A case of a patient with histoid leprosy living in the Northeast Region of Brazil is reported.

Case for diagnosis. Keloidal cord-like lesion on the leg

Abstract We report a 74-year-old male presented to an outpatient dermatology clinic in Manaus, Amazonas, with a one-year history of pruritic, keloidal lesions on his left lower extremity. Histopathology showed round structures in reticular dermis. Grocott methenamine silver stain revealed numerous round yeasts with thick double walls, occurring singly or in chains connected by tubular projections. The diagnosis was lobomycosis. Although the keloidal lesions presented by this patient are typical of lobomycosis, their linear distribution along the left lower limb is unusual.

What is your diagnosis? Keloidal cord-like lesion on the leg.

We report a 74-year-old male presented to an outpatient dermatology clinic in Manaus, Amazonas, with a one-year history of pruritic, keloidal lesions on his left lower extremity. Histopathology showed round structures in reticular dermis. Grocott methenamine silver stain revealed numerous round yeasts with thick double walls, occurring singly or in chains connected by tubular projections. The diagnosis was lobomycosis. Although the keloidal lesions presented by this patient are typical of lobomycosis, their linear distribution along the left lower limb is unusual.

An atypical keloid in a Brazilian man.

Case report from French Guiana of an atypical keloid in a Brazilian man: Lobomycosis. Lobomycosis is a rare fungal skin infection, endemic to the Amazon basin. Its clinical manifestations are slow-growing keloid-like nodules, with a granulomatous reaction on histopathology. The etiological agent, Lacazia loboi, has never been isolated in the environment or cultured in a laboratory. Diagnosis is based on the typical appearance on microscopy. Treatment is disappointing, with a high recurrence rate. We report a new case in French Guiana and review the literature. Only 10 cases have been reported outside of the endemic area, 2 involving no travel; the mean time to diagnosis was 21 years. Phylogenetic analysis has recently proved that lobomycosis in dolphins is caused by a fungus more closely related to Paracoccidioides brasiliensis than to L. loboi (two very closely related species). Molecular diagnosis is possible in a few centers. Climate change may result in spreading lobomycosis to currently disease-free areas of the world.

Lobomycosis: a therapeutic challenge.

Lobomycosis or lacaziosis is a chronic granulomatous fungal infection caused by Lacazia loboi. Most cases are restricted to tropical regions. Transmission is believed to occur through traumatic inoculation in the skin, mainly in exposed areas. It is characterized by keloid-like nodules. There are only a few hundred cases reported. The differential diagnoses include many skin conditions, and treatment is difficult. The reported case, initially diagnosed as keloid, proved to be refractory to surgical treatment alone. It was subsequently approached with extensive surgery, cryotherapy every three months and a combination of itraconazole and clofazimine for two years. No signs of clinical and histopathological activity were detected during follow-up.

Lobomycosis: a therapeutic challenge

Abstract: Lobomycosis or lacaziosis is a chronic granulomatous fungal infection caused by Lacazia loboi. Most cases are restricted to tropical regions. Transmission is believed to occur through traumatic inoculation in the skin, mainly in exposed areas. It is characterized by keloid-like nodules. There are only a few hundred cases reported. The differential diagnoses include many skin conditions, and treatment is difficult. The reported case, initially diagnosed as keloid, proved to be refractory to surgical treatment alone. It was subsequently approached with extensive surgery, cryotherapy every three months and a combination of itraconazole and clofazimine for two years. No signs of clinical and histopathological activity were detected during follow-up.

Keloidectomy with core fillet flap and intralesional verapamil injection for recurrent earlobe keloids.

BACKGROUND: Earlobe keloids are usually recalcitrant to treatment and have a high rate of recurrence. Verapamil is a calcium channel antagonist that has been shown to inhibit the synthesis/secretion of extracellular matrix molecules and increase collagenase. OBJECTIVES: This prospective study was designed to evaluate the results of treatment of recurrent earlobe keloids using keloidectomy with core fillet flap and intralesional verapamil injection. METHODS: Nineteen keloids in 16 patients were treated using this technique with intralesional verapamil injection given intraoperatively, then every 2 weeks for 3 months, with postoperative follow-up for 18 months. RESULTS: Fourteen patients completed the study. Ten patients (71.4%) showed response to treatment. Four (28.6%) cases showed recurrence, two (14.2%) at the wound bed and another two (14. 2%) at the incision line. Eighty percent of responders were highly satisfied with their treatment. CONCLUSION: Keloidectomy with core fillet flap and intralesional verapamil injection is a reliable and cost-effective method in the treatment of recurrent earlobe keloids with a low rate of recurrence and high patient satisfaction.

Histoid Leprosy Presenting with Keloid Like Lesions.

A 42 year old male presented with multiple, discrete, hyperpigmented, firm, non elastic, non tender papules and plaques on the posterior trunk of 5 months duration, resembling keloid. The patient had also a few skin colored papules on the anterior trunk and face. The sensations over the skin lesions were intact. The patient had glove and stocking type of anesthesia and bilaterally thickened, non tender peripheral nerve trunks. The slit skin smear for acid fast bacilli from the ear lobes, skin lesions and normal skin were highly positive for Mycobacterium leprae. A skin biopsy showed a well defined collection of spindle shaped histiocytes in the dermis packed with acid fast bacilli. We are presenting here a case of histoid leprosy presenting with keloid like lesions, probably the rarest presentation of histoid leprosy.

Genome-wide association study of skin complex diseases.

Complex diseases are caused by both genetic and environmental factors. Over decades, scientists endeavored to uncover the genetic myth of complex diseases by linkage and association studies. Since 2005, the genome-wide association study (GWAS) has been proved to be the most powerful and efficient study design thus far in identifying genetic variants that are associated with complex diseases. More than 230 complex diseases and traits have been investigated by this approach. In dermatology, 10 skin complex diseases have been investigated, a wealth of common susceptibility variants conferring risk for skin complex diseases have been discovered. These findings point to genes and/or loci involved in biological systems worth further investigating by using other methodologies. Certainly, as our understanding of the genetic etiology of skin complex diseases continues to mature, important opportunities will emerge for developing more effective diagnostic and clinical management tools for these diseases.

Standard guidelines of care: Keloids and hypertrophic scars.

Keloids and hypertrophic scars (HTS) are the result of overgrowth of fibrous tissue, following healing of a cutaneous injury, and cause morbidity. There are several treatment modalities which are useful for the management of keloids, though no single modality is completely effective. The most commonly used modalities are pressure, silicone gel sheet, intralesional steroids, 5-fluorouracil (5 FU), cryotherapy, surgical excision, and lasers. They may be used either singly or, as is done more commonly, in combinations. Any qualified dermatologist who has attained postgraduate qualification in dermatology can treat keloids and HTS. Some procedures, such as cryosurgery and surgical excision, may require additional training in dermatologic surgery. Most modalities for keloids, including intralesional injections and mechanical therapies such as pressure and silicone gel based products, can be given/prescribed on OPD basis. Surgical excision requires a minor operation theater with the facility to handle emergencies. It is important to counsel the patient about the nature of the problem. One should realize that keloid will only improve and not disappear completely. Patients should be informed about the high recurrence rates. Different modalities carry risk of adverse effects and complications and the treating physician needs to be aware of these and patients should be informed about them.