Cytokeratin expression in lichen amyloidosus and macular amyloidosis

34βE12 is the Most Reliable Marker for Keratin-Derived Cutaneous Amyloid: A Comparative Study

ABSTRACT

Congo red (CR) remains the most commonly used stain by pathologists to detect amyloid deposition. CR, however, has limitations including variable sensitivity with potential of false negative results. We investigated the staining intensity of CR in comparison to commercially available cytokeratin immunohistochemical markers in a series of primary cutaneous amyloidosis originating from keratin filaments.

Primary Localized Cutaneous Nodular Amyloidosis on Scalp Successfully Treated with Excision

Primary localized cutaneous nodular amyloidosis (PLCNA) is the rarest form of cutaneous amyloidosis, characterized by nodular deposits of light chain amyloids in the dermis and subcutaneous tissue, without apparent systemic involvement. One or several nodules are preferably located on the extremities, trunk, or face. The most useful stain for detecting amyloid fibrils is Congo red, which, when combined with polarized light, makes amyloid proteins appear apple-green under a microscope. Immunohistochemical staining can help identify the exact type of amyloid proteins. Although the exact etiology of PLCNA is unclear, removal of nodules by shaving or surgical excision has shown good results. To the best of our knowledge, only seven cases of PLCNA have yet been reported in the Korean literature. In three of these cases, the patients had lesions on the scalp. Herein, we present a case of a 34-year-old male with PLCNA on the scalp with all the results of immunohistochemical evaluation.

Proteomic analysis shows that the main constituent of subepidermal localised cutaneous amyloidosis is not galectin-7

Lichen or macular localised cutaneous amyloidoses have long been described as keratinic amyloidoses and believed to be due to the deposition of cytokeratin peptides originating from epidermis in the dermal papillae. However, recently it was suggested that galectin-7 is the causative protein for this type of amyloidosis. This was based on the detection of galectin-7 in a biopsy from a patient diagnosed with Bowen's disease and localised cutaneous amyloidosis. In this study we report mass spectrometry-based proteomic analysis of the protein composition of localised cutaneous amyloid deposits from seven patients using laser microdissection and show that basal keratins are the main constituents of the amyloid deposits. Galectin-7 was not present in the dermal amyloid deposits and was only present in the overlying Congo red negative epidermis.

Comparison of Immunostaining with Hematoxylin-Eosin and Special Stains in the Diagnosis of Cutaneous Macular Amyloidosis

Background

Although macular amyloidosis is a relatively rare disease, it is a common cutaneous disease in Asia and the Middle East. On hematoxylin and eosin (H&E) stained slides, early lesions could easily be missed without the use of special stains and/or immunohistochemistry.

Methods

We enrolled 42 patients with the clinical impression of macular amyloidosis who had undergone two 4-mm punch biopsies from 2015 to 2016 at a dermatology clinic affiliated to Shiraz University. Besides, 14 cases with a clinical diagnosis other than macular amyloidosis were selected as the negative control group. Congo red, crystal violet, and immunohistochemical (IHC) staining of CK5 and high molecular weight keratin (HMWK) were performed for each specimen.

Results

H&E slides showed globular depositions in 15 (35.7%) out of 42 patients. None of the patients showed apple-green birefringence with Congo red stain. Evaluation of crystal violet stained sections revealed purplish violet amyloid deposits in 15 (35.7%) patients. IHC study showed expression of CK5 in 52.4% and HMWK in 50% of the patients, which was not a significant difference (p = 0.715). The findings of both IHC markers had a significant difference with H&E stains (p = 0.039) and crystal violet (p = 0.008). Additionally, we found that two punch biopsies from two sites in the involved area did not have a significant preference over one punch biopsy. All of the cases in the control group were negative for amyloid deposition in H&E, special stains, and IHC stained slides as expected.

Conclusions

IHC evaluation using CK5 and HMWK might be a useful tool for diagnosing macular amyloidosis.

Clinicopathological evaluation of patients with rippled pattern pigmentation of the skin: A single-center study

The aim of the present study was to investigate the clinical association between rippled pattern pigmentation and the positivity of histopathological analysis for amyloid. A total of 50 patients (90% women) with rippled pattern pigmentation referring to Dermatology Clinic of Shahid Faghihi Hospital, Shiraz, Iran, in 2015 participated in this study. Two biopsies were performed for all the cases from the most frequently affected sites. The specimens were evaluated for amyloid deposits with hematoxylin-eosin (H&E), Congo red (CR), and crystal violet (CV) stains. The upper back was the most frequently affected area in the patients. Family history (28%), atopy (14%), pruritus as a common finding (86%), and history of friction (54%) were positive. The prevalence of disease was higher in patients with skin photo Type 3. Amyloid deposit was not detected in most patients by these stains. No statistically significant difference was found between the amyloid positive cases stained with H&E, CR, and CV (p-value > 0.05). Only the difference in positive results between biopsy number 2 and the total biopsy (1 and 2) was significant (p-value < .05). In conclusion, it seems that it is useful to increase the number of biopsies and other more sensitive staining methods to detect small focal amyloid deposits.

A Rare Presentation of Nodular Amyloidosis on the Lower Back

Primary localized cutaneous amyloidosis (PLCA) occurs when amyloid is deposited only within the skin and there is no evidence of systemic involvement. Nodular amyloidosis is the rarest subtype of PLCA. It typically involves the acral regions but can sometimes present on the head and neck. The condition usually presents clinically as a single tan or yellow nodule or plaque that may appear waxy. Herein, we present a rare case of a 66-year-old man with nodular amyloidosis on the lower back.

Comparative proteomics analysis of primary cutaneous amyloidosis

Primary cutaneous amyloidosis (PCA) is a localized skin disorder that is characterized by the abnormal deposition of amyloid in the extracellular matrix (ECM) of the dermis. The pathogenesis of PCA is poorly understood. The objective of the present study was to survey proteome changes in PCA lesions in order to gain insight into the molecular basis and pathogenesis of PCA. Total protein from PCA lesions and normal skin tissue samples were extracted and analyzed using the isobaric tags for relative and absolute quantitation technique. The function of differentially expressed proteins in PCA were analyzed by gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) and protein-protein interaction analysis. The proteins that were most upregulated in PCA lesions were further analyzed by immunohistochemistry. A total of 1,032 proteins were identified in PCA lesions and control skin samples, with 51 proteins differentially expressed in PCA lesions, of which 27 were upregulated. In PCA lesions, the upregulated proteins were primarily extracellulary located. In addition, GO analysis indicated that the upregulated proteins were significantly enriched in the biological processes of epidermal development, collagen fiber organization and response to wounding (adjusted P<0.001). KEGG analysis indicated that the upregulated proteins were significantly enriched in the signaling pathways of cell communication, ECM receptor interaction and focal adhesion (adjusted P<0.001). Furthermore, the upregulated proteins were enriched in the molecular function of calcium ion binding, and the calcium binding proteins calmodulin-like protein 5, S100 calcium-binding protein A7 (S100A7)/fatty-acid binding protein and S100A8/A9 exhibited the highest levels of upregulation in PCA. This analysis of differentially expressed proteins in PCA suggests that increased focal adhesion, differentiation and wound healing is associated with the pathogenesis of PCA.

A familial poikiloderma-like cutaneous amyloidosis

Familial poikiloderma-like cutaneous amyloidosis(FPLCA) is a rare, generalized but genetic dyschromic skin disorder characterized by amyloid deposits in dermis due to defective DNA repair secondary to sunlight damage. Clinically, it presents with diffuse brownish pigmentation with hypo-pigmented macules and many brownish scattered lichenoid papules with normal developmental milestones. The condition is autosomal dominant with incomplete penetrance. We are here reporting a rare familial case of FPLCA with a review of the literature

Cutaneous deposits

: The cutaneous deposition disorders are a group of unrelated conditions characterized by the accumulation of either endogenous or exogenous substances within the skin. These cutaneous deposits are substances that are not normal constituents of the skin and are laid down usually in the dermis, but also in the subcutis, in a variety of different circumstances. There are 5 broad categories of cutaneous deposits. The first group includes calcium salts, bone, and cartilage. The second category includes the hyaline deposits that may be seen in the dermis in several metabolic disorders, such as amyloidosis, gout, porphyria, and lipoid proteinosis. The third category includes various pigments, heavy metals, and complex drug pigments. The fourth category, cutaneous implants, includes substances that are inserted into the skin for cosmetic purposes. The fifth category includes miscellaneous substances, such as oxalate crystals and fiberglass. In this article, the authors review the clinicopathologic characteristics of cutaneous deposition diseases, classify the different types of cutaneous deposits, and identify all the histopathologic features that may assist in diagnosing the origin of a cutaneous deposit.

Cutaneous amyloidosis: a concept review

Concepts and semantics are crucial for good communication between clinicians and pathologists. Amyloidosis was described more than 150 years ago. Therefore, the terminology related to it is abundant, varied, and sometimes complex. In this report, we intend to discuss several terms related to the disease, with special emphasis on cutaneous amyloidosis. We present a review, from Virchow to present, of the concepts related to amyloidosis: its nature, the classification of cutaneous forms of the disease, and the techniques used in its diagnosis.

Primary cutaneous amyloidosis of the external ear: a clinicopathological and immunohistochemical study of 17 cases

Primary cutaneous amyloidosis includes several forms of localized amyloidosis characterized by superficial amyloid deposits occurring at or near the dermal-epidermal junction in the absence of systemic involvement. Primary cutaneous amyloidosis of the auricular concha and external ear represents a rarely described variant. There have been 27 cases reported in the English language literature, and herein we report 17 additional cases. This article demonstrates that the amyloid observed in this context is generally positive for Congo red, crystal violet and thioflavin T. It also expresses cytokeratin 34ßE12 via immunohistochemistry. Our immunohistochemical results and review of the literature suggest that the amyloid in amyloidosis of the external ear is the result of basal keratinocyte degeneration and does not signify deposition from a systemic or generalized process.

Pretibial dystrophic epidermolysis bullosa with localized cutaneous amyloidosis: coincidental or secondary amyloidosis?

Here, we describe the case of a patient with pretibial dystrophic epidermolysis bullosa (PDEB) with amyloid deposition. The patient was a 40-year-old Japanese woman who presented a blistering eruption in the pretibial area with flat violaceous-brown lichenoid papules. The histology of the blister revealed a subepidermal bulla with antibodies bound to basement membrane antigens on the blister roof by immunoflourescent mapping. Electron microscopy revealed a blister cleavage plane below the lamina densa. The histology of the lichenoid papules showed amyloid deposition in the papillary dermis. Because it was confined to just beneath the bulla base of the blister specimen, the amyloid deposition may have been derived from degenerated keratinocytes induced by damage to the epidermal-dermal junction due to blister formation in PDEB in this case. PDEB, in general, is often misdiagnosed as lichen amyloidosis; however, some PDEB cases could actually be associated with amyloid deposition.

Successful treatment of lichen amyloidosis with combined bath PUVA photochemotherapy and oral acitretin

Lichen amyloidosis (LA) is a chronic, pruritic skin disorder characterized by brownish-grey papules on extensor surfaces of legs and rarely on the trunk. Thioflavin T-positive amyloid deposits are found in the papillary dermis of affected skin, which is the only organ involved. A variety of therapeutic regimens for lichen amyloidosis have been described; however, in many cases with only limited effect. We report on two patients with lichen amyloidosis with typical clinical symptoms not responding to local treatment. A combined regimen with bath psoralen ultraviolet A (PUVA) and oral acitretin was initiated, resulting in nearly complete resolution of the papules and impressive relief from the severe pruritus. The beneficial response has persisted for 8 months. The suggested combined therapy with bath PUVA photochemotherapy and oral acitretin represents an efficacious and practical treatment modality for lichen amyloidosis with long-lasting effects.

Primary cutaneous amyloidosis of the auricular concha: case report and review of published work

A 70-year-old Japanese female developed tiny papules on her bilateral ears 2 years previously. A histological study of a biopsy specimen revealed that amorphous materials were present in the widened dermal papillae. Because these materials were positive for both Congo red and Dylon, we diagnosed the lesion as primary cutaneous amyloidosis of the auricular concha. Immunohistochemically, the amyloid substance stained positively with 34betaE12 (cytokeratin 1/5/10/14), suggesting that it had an epidermal origin. Seven reported cases of this unique disorder were also reviewed.