Amyloidogenesis in organ-limited cutaneous amyloidosis: an antigenic identity between epidermal keratin and skin amyloid

Epidermal keratin was extracted and antibody against this protein was produced in rabbits. Various forms of organ-limited cutaneous amyloidosis (lichenoid, macular, and nodular amyloidosis, and basal cell epithelioma) and primary systemic amyloidosis were immunohistochemically examined to test the identity between epidermal keratin and skin amyloid. Amyloids in lichenoid and macular amyloidoses, and in basal cell epithelioma had an identical antigenicity with epidermal keratin, whereas amyloids in nodular amyloidosis and systemic amyloidosis did not have this identity. In addition, amyloid in lichen amyloidosis contained disulfide bonds as in keratin. Connective tissue components including filaments of fibroblasts and vascular endothelial cells did not react with this antikeratin antibody. It was concluded that at least some of the amyloid substance in organ-limited cutaneous amyloidosis is derived from degenerated epidermal keratinocytes through filamentous degeneration or apoptosis.     

Immunohistochemical staining properties of amyloids with anti-keratin antibodies using formalin-fixed, paraffin-embedded sections

Immunohistochemical staining properties of amyloids with anti-keratin antibodies were investigated using an avidin-biotin-peroxidase complex (ABC) system on formalin-fixed, paraffin-embedded sections. Anti-keratin antibody EAB-903 which recognize 66K and 57K daltons keratin peptides reacted with amyloid deposits in both lichen amyloidosus (LA) and macular amyloidosis (MA), but did not react with either primary systemic amyloidosis (AL), secondary systemic amyloidosis (AA) or heredofamilial amyloid polyneuropathy (AF). However, anti-keratin antibodies EAB-904 and MAK-6 did not react with any types of amyloids. These results suggested that immunohistochemical staining with anti-keratin antibody EAB-903 using formalin-fixed, paraffin-embedded sections appeared to be a useful method in making differential diagnosis of primary localized cutaneous amyloidosis (AD).     

Immunohistochemical study on keratin expression in certain cutaneous epithelial neoplasms. Basal cell carcinoma, pilomatricoma, and seborrheic keratosis

We investigated immunohistochemically 20 basal cell carcinomas (BCC), five pilomatricomas, and nine seborrheic keratoses using anti-BCC keratin monoclonal antibody (BKN-1) and anti-hair keratin monoclonal antibodies (HKN-2, HKN-4- -7). The neoplastic cells in all the cases of BCC were always uniformly stained by BKN-1, HKN-2, and HKN-4, indicating that the BCC cells display a constant antigenicity of keratin, which may be different from that of the normal epidermis. Although no fluorescence by HKN-6 or HKN-7 was seen in any cases of BCC, HKN-5 partially but strongly stained the neoplastic nests in most cases of BCC; BCC may have differentiation toward the lower part of hair follicular epithelium. In pilomatricoma, all the anti-keratin monoclonal antibodies showed a similar staining pattern; the differentiating neoplastic cells undergoing transition from basaloid to eosinophilic were positively stained by each antibody in all the cases. This finding of pilomatricoma corresponds to that of the differentiating cells in the inner hair layers, especially in the hair cortex. In seborrheic keratoses, no fluorescence was recognized with HKN-5- -7, which stain the lower follicular cells in the normal human skin. The staining patterns of seborrheic keratosis by BKN-1, HKN-2, and HKN-4 were similar to those of the normal interfollicular epidermis. These anti-keratin monoclonal antibodies seem to be useful for the investigation of the direction of differentiation of skin adnexal neoplasms.     

Cell differentiation in human anagen hair and hair follicles studied with anti-hair keratin monoclonal antibodies

By a hybridoma technique using BALB/c mice and Sp2/0-Ag14 mouse myeloma cells, monoclonal antibodies against hair fibrous proteins (HFP) were produced. Two monoclonal antibodies, designated as HKN-5 and HKN-7, were chosen. Either HFP or epidermal fibrous proteins (EFP) were electrophoretically separated on polyacrylamide gels with sodium dodecyl sulfate. By immunoblot analyses, HKN-5 and HKN-7 decorated the electrophoretic bands of HFP but not those of EFP. Immunohistochemically, these monoclonal antibodies stained the medulla, cortex, cuticle, and inner root sheath in the keratogenous zone of anagen hairs, but not hair matrix cells. HKN-5 further reacted with the innermost cells (IMC) of the outer root sheath; these cells formed a single cell layer located outside of the Henle's layer. HKN-7 did not react with the outer root sheath including the IMC. Neither monoclonal antibody reacted with any other skin components or any tissues of other organs examined. Ultrastructurally, the IMC of the outer root sheath showed a unique cell differentiation forming an independent cell layer. It is suggested that the cells in the medulla, cortex, cuticle, and inner root sheath of anagen hair and hair follicles possess a similar keratin expression and that the IMC of the outer root sheath display a unique keratin expression and their own cell differentiation, resulting in 2 types of keratinization of the outer root sheath; keratinization of IMC and trichilemmal keratinization.     

Immunohistochemical studies on fibrillin in amyloidosis, lichen ruber planus and porphyria.

The pathogenesis of macular amyloidosis and lichen amyloidosis remains unsolved and the primary amyloid fibril protein(s) has not yet been identified. Ultrastructural association of skin amyloid with elastin associated microfibrils has been noted earlier. The presence of fibrillin in conjunction with such microfibrils was recently demonstrated immunohistochemically. The presence of fibrillin immunoreactivity in the amyloid deposits in skin biopsies from 3 patients with macular amyloidosis and 3 patients with lichen amyloidosis was studied, using monoclonal anti-fibrillin antibodies. For comparison, skin specimens were studied from five patients with lichen ruber planus, four patients with erythropoietic protoporphyria and from a patient with myeloma-associated cutaneous amyloidosis. Renal specimens from two cases of the amyloid A type of renal amyloidosis also were investigated. There was no immunostaining either of the keratin bodies in specimens of lichen ruber planus, the cutaneous PAS-positive vascular deposits in patients with erythropoietic protoporphyria, or the amyloid deposits in specimens of systemic amyloidosis and it was faint or absent in amyloid deposits in the specimens from patients with lichen amyloidosis. In contrast, distinct fibrillin immunoreactivity could be demonstrated in amyloid deposits in specimens from patients with macular amyloidosis. It was sometimes absent in deposits located in the upper part of the papillary dermis, close to the dermal epidermal junction zone, while consistently strong in deposits located lower down in the dermis. The results suggest that fibrillin or part of the fibrillin molecule may be present in some of the amyloid deposits in specimens of macular amyloidosis.     

Immunofluorescence and histochemical studies of localized cutaneous amyloidosis

Lichen amyloidosus (LA) and macular amyloidosis (MA) are two forms of localized cutaneous amyloidosis in which the amyloid occurs as larger and smaller deposits respectively in the papillary dermis. The histogenesis of the amyloid of these conditions is unknown. By using an indirect immunofluarescence technique we showed that LA and MA do not react with antibodies against different previously characterized amyloid fibril proteins. These results indicate that the amyloid of LA and MA is different from other known types of amyloid. Protein AP, which was demonstrated in amyloid of MA and LA, is known to be present in all forms of amyloid and is of unknown significance. Antiserum against keratin did not react with the larger homogeneous amyloid bodies, but showed a weak reaction with some small deposits. Histochemical staining failed to show keratin in any of the tissues containing LA or MA.     

Further Immunocytochemical Characterization of Cultured Hair Apparatus Cells

In immunocytochemical studies of cultured hair apparatus cells we employed anti-hair keratin monoclonal antibodies (HKN-2, HKN-4, HKN-5, HKN-6 and HKN-7) and compared the results with electron microscopic studies. On day 1, the cultured cells positively stained with HKN-2 (52%), HKN-4 (50%), HKN-5 (43%), HKN-6 (33%), or HKN-7 (37%). On day 3, more than 88% of the cells showed no reaction to any antibody. On day 6, most of the cells stained with all of the antibodies: HKN-2 (96%), HKN-4 (92%), HKN-5 (80%), HKN-6 (72%) and HKN-7 (74%). These reactivities were maintained until day 13. Electron microscopic studies revealed that, on day 1, half of the observed cells were immature and 47% of them were already differentiated. Most (88%) of the cells showed immature features and the percentage of differentiated cells had decreased by day 3. The differentiated cells (87%) reappeared by day 6, and degenerated cells (63%) increased by day 13. These immunocytochemical results were consistent with those of simultaneous electron microscopic studies, demonstrating that immature cells proliferated and differentiated into subpopulations of each hair apparatus layer type, including the outer root sheath cells, in this culture system.     

Cytokeratins in primary cutaneous amyloidosis

The expression of keratins was investigated immunohistochemically on formalin-fixed and snap-frozen primary cutaneous amyloidosis tissue with a panel of monospecific and polyspecific antikeratin antibodies which recognized keratins K1, K5, K6, K7, K8, K10, K14, K16, K17, K18, and K19. Amyloid deposits in frozen section of seven cases of macular amyloidosis and lichen amyloidosus always reacted with antibodies LP34 (labeling K5, K6 and K18) MNF (labeling K5, K6, K8, K10, K17 and K18) and RCK 102 (labeling K5 and K8); frozen section in one case each of the seven cases also reacted with antibodies LL001 (labeling K14), Lp1K (labeling K7 and K17), and LP2K (labeling K19), LP1K (labelling K7 and K17), and LP2K (labelling K19), In formalin fixed section of 13 cases of macular amyloidosis and lichen amyloidosus amyloid deposits were labeled with LP34 in three section LL020 ()labelling keratins K5 and K6) in one section and LP2K in two section. In nodular primary cutaneous amyloidosis amyloid deposits were not labeled with any antikeratin antibodies. These data confirm that amyloid in macular amyloidosis and lichen amyloidosus contains keratin epitopes, and suggests derivation of the fibrillar component from keratin intermediate filaments Several different keratins appear to undergo conversion to amyloid, LP34, MNF 116 and RCK 102 antibodies, which have in common the labelling of keratin K5, may be useful in the diagnosis of macular and popular amyloidosis with frozen tissue section.     

Sulfhydryl and disulfide stainings in amyloids of skin-limited and systemic amyloidoses

Disulfide (S-S) bonds and sulfhydryl (-SH) groups in skin-limited and systemic amyloidoses in frozen and paraffin-embedded sections were examined with a thiol reagent, N-(7-dimethylamino-4-methyl-3-coumarinyl)-maleimide (DACM). In frozen sections, dermal amyloids of skin-limited amyloidoses contained a large number of S-S bonds but no -SH groups [macular amyloidosis (9 cases), lichen amyloidosis (4), and skin tumor-associated (seborrheic keratosis) amyloidosis (1)]. In contrast, amyloids of systemic amyloidoses contained no S-S bonds or -SH groups [primary and myeloma-associated amyloidoses (1 each)]. The identical results were obtained from paraffin-embedded sections in skin-limited amyloidoses [macular (31), biphasic (4), lichenoid (9) and skin tumor-associated Bowen's disease (3), seborrheic keratosis (2), solar keratosis (2), porokeratosis Mibelli (1), and basal cell epithelioma (1) amyloidoses], systemic amyloidoses [primary (3), myeloma-associated (2), and secondary (2) amyloidoses] and tumefactive amyloidoses of the tongue (2). Furthermore, amyloid-like deposits confirmed by various histochemical stainings were found in the epidermis in 27/67 cases of skin-limited amyloidoses in both frozen and paraffin sections. These intraepidermal amyloid-like deposits contained S-S bonds in all cases (27/27) and -SH groups in 10 of 27 cases. In contrast, an intraepidermal amyloid-like deposit was not observed in any systemic amyloidoses (0/9) or tumefactive amyloidoses of the tongue (2). These results showed that skin-limited amyloidoses could be differentiated from systemic amyloidoses by DACM methods (this appears to depend upon the differences of amino acid composition between skin-limited and systemic amyloidoses) and that paraffin-embedded sections were usable for DACM methods. Present study further suggests that amyloids ion skin-limited amyloidoses are, at least in part, derived from epidermal keratinocytes.     

Lamina densa malformation involved in histogenesis of primary localized cutaneous amyloidosis.

Skin lesions of lichenoid amyloidosis and macular amyloidosis were immunohistochemically investigated using five monoclonal antibodies against basement membrane zone (BMZ) components. A hemidesmosomal component did not contribute to amyloid deposits, but components of the lamina densa and anchoring fibrils were associated with amyloid deposits in the uppermost dermis. Immunoelectron microscopy revealed that these BMZ components were not only aggregated in the BMZ and dermis, but were also involved in the individual amyloid islets. The lamina densa was disrupted in the interface areas just above the amyloid deposits, where cytoplasm of the basal cells directly faced the aggregate of amyloid filaments. Aggregates of some BMZ components were continuous to the amyloid islets from the lamina densa area. These findings suggest that a lamina densa malformation is involved in amyloid production in the interface of the BMZ, and support the secretion theory rather than the fibrillar body theory of amyloidogenesis in these types of primary localized cutaneous amyloidosis.     

Immunologic characteristics of keratins in extramammary Paget's disease

Six cases of extramammary Paget's disease were immunohistochemically investigated with several antikeratin monoclonal antibodies. Paget cells and surrounding epidermal keratinocytes were equally stained with an antikeratin monoclonal antibody, HKN-4, which recognizes a broad spectrum of keratins. However, Paget cells were clearly distinguished from the surrounding epidermal keratinocytes by HKN-2, which does not react with keratins of secretory cells but does react with keratins of ductal and myoepithelial cells of sweat glands and with epidermis and hair tissue of the normal skin. The HKN-2 did not bind to Paget cells, but the surrounding keratinocytes were positive. CK7, LE41, RGE53, and LP2K, which recognize simple epithelium-type keratins 7 (molecular weight [MW], 54,000; type II), 8 (MW, 52,500; type II), 18 (MW, 45,000; type I), and 19 (MW, 40,000; type I), respectively, stained Paget cells but not the surrounding keratinocytes. Two cases of Merkel cell carcinoma, examined as controls, showed positivity to LE41 and RGE53 but not to CK7 and LP2K. Since in the normal skin the secretory cells of sweat glands showed the same keratin expression as that of Paget cells, Paget cells of extramammary Paget's disease may be derived from or differentiate to the secretory cells of sweat glands.     

Anti-hair keratin monoclonal antibody (HKN-2)

BALB/c mice were immunized with human hair fibrous proteins. Then their spleen cells were fused with Sp2/0-Agl4 mouse myeloma cells. Antibody-producing hybridomas were selected by ELISA method and cloned by limiting dilution. A monoclonal antibody was chosen and designated as HKN-2. Immunohistochemically, on frozen sections of normal human skin, HKN-2 was found to recognize the suprabasal cells of epidermis and hair follicle, the cells in the keratogenous zone of hair shaft, the sebaceous cells and the ductal and myoepithelial cells of sweat glands. The basal cells of the epidermis and lower hair follicle, hair matrix cells and secretory cells of sweat glands did not react with HKN-2. An immunoelectron microscopic method showed that the positive reaction to HKN-2 was located on the tonofilaments in the cytoplasm. It was concluded that there might be a common antigenic determinant between hair and other skin epithelial tissues. A complexity in keratin manifestation in each epithelial tissue of the skin was suspected.     

Antikeratin autoantibodies in the amyloid deposits of lichen amyloidosus and macular amyloidosis

Summary In order to characterize immunoglobulins found on amyloid deposits of lichen amyloidosus and macular amyloidosis, an elution from cryostat sections was performed with citrate buffer, glycine buffer, NaCl, and PBS. Resulting eluates (mainly IgG) were examined with dot immunoblotting and SDS-PAGE immunoblotting and were found to react with the human epidermal keratin of 50 and 67 kD. Antikeratin autoantibody activities in normal murine and human sera were examined using a dot immunoblotting assay. In murine sera, titers of IgG and IgM autoantibodies were higher in older mice. The human cord blood showed significantly lower IgM autoantibody titers, whereas IgG antibody titers showed no significant differences from adults' sera, probably due to the permeability of IgG through the placental barrier. A stronger antibody activity in older individuals was thought to be due to the repeated exposures to keratin proteins derived from apoptotic keratinocytes. Sera from lichen amyloidosus and macular amyloidosis patients did not show any difference from normal controls in their antikeratin titers. It was concluded that the patients with lichenoid or macular amyloidosis are capable of producing a normal level of antikeratin autoantibodies. However, the removal of opsonized keratin-type amyloid from the skin is slow or deficient due to as yet unknown factors.Part of this study was reported on May 5, 1987 at the 48th Annual Meeting of the Society for Investigative Dermatology at San Diego, CA, USA     

Advanced glycation end product-modified beta2-microglobulin is a component of amyloid fibrils of primary localized cutaneous nodular amyloidosis

Primary localized cutaneous nodular amyloidosis is a rare form of cutaneous amyloidosis. Amyloid fibrils in primary localized cutaneous nodular amyloidosis have been reported to be originated from immunoglobulin light chains. Immunohistochemical studies on the lesional skins of four patients with primary localized cutaneous nodular amyloidosis demonstrated that amyloid deposits of all cases showed a positive reaction with the antibodies for beta2-microglobulin and advanced glycation end products as well as immunoglobulin light chain (kappa or lambda). No beta2-microglobulin and advanced glycation end product immunoreactivity was found in the amyloid deposits of other primary localized cutaneous amyloidosis (lichen amyloidosis and macular amyloidosis). Double immunofluorescence study of the lesional skin of primary localized cutaneous nodular amyloidosis showed that anti-kappa light chain, anti-beta2-microglobulin and anti-advanced glycation end product antibodies mostly reacted with the same area of amyloid deposit. Amyloid proteins were sequentially extracted with distilled water from one case of primary localized cutaneous nodular amyloidosis and recovered in the five water-soluble fractions (fractions I-V). Immunoblot assay of amyloid fibril proteins demonstrated that immunoreactive polypeptides with anti-kappa light chain antibody (29 kDa) and with anti-beta2-microglobulin antibody (12 kDa) were detected in fractions I-V, whereas immunoreactive polypeptide with anti-advanced glycation end product antibody (12 kDa) was detected exclusively in fractions III-V but not in fractions I and II. Two-dimensional polyacrylamide gel electrophoresis revealed that 12 kDa polypeptide in fractions I and II was electrophoretically identical with authentic beta2-microglobulin and that beta2-microglobulin in fractions III-V was advanced glycation end product-modified beta2-microglobulin with more acidic pI value. These results indicate that beta2-microglobulin is another major component of amyloid fibrils in primary localized cutaneous nodular amyloidosis and that beta2-microglobulin in primary localized cutaneous nodular amyloidosis is partly subjected to the modification of advanced glycation end product.     

Therapeutic removal of amyloid deposits in cutaneous amyloidosis by localised intra‐lesional injections of anti‐amyloid antibodies

Please cite this paper as: Therapeutic removal of amyloid deposits in cutaneous amyloidosis by localised intra‐lesional injections of anti‐amyloid antibodies. Experimental Dermatology 2010; 19 : 904–911. Abstract: In the skin, amyloidosis can be found with or without systemic disease. Primary cutaneous amyloidosis defines those amyloidoses restricted to the skin without involvement of other systems. Here, we used conformation‐specific antibodies to characterise both fibrillar and oligomeric amyloid aggregates in the skin from patients with cutaneous amyloidosis. Localised cutaneous amyloidosis with different morphology was reproduced in mice by intra‐dermal (i.d.) and subdermal administration of amyloid‐enhancing factor. Moreover, we demonstrated that conformational antibodies were effective in clearing amyloid deposits caused by localised intra‐lesional injections without the necessity of an immune response. Given the accessibility and amyloid localization in this disease, direct i.d. injections of conformational antibodies could be a convenient and direct method for treatment.     

Cutaneous lymphatic amyloid deposits in "Hungarian-type" familial transthyretin amyloidosis: a case report

Multiple transthyretin (TTR) mutations have recently been identified and implicated in the development of familial systemic amyloidoses, but early diagnosis of these disorders is still largely unresolved. We investigated the presence and tissue distribution of TTR-derived amyloid in skin biopsies of a 59-year-old woman carrying the "Hungarian-type" mutation of TTR (Asp18Gly). Clinical symptoms involved severe central nervous system dysfunction without signs of polyneuropathy, also referred to as the "central form" of TTR-related systemic amyloidosis. Skin biopsy was also evaluated as a tool in order to diagnose this type of TTR amyloidosis. Biopsy samples were collected from the infra-axillary region. Light microscopy using Congo red and polarized light was used to diagnose amyloid deposits. Subsequently, electron microscopic analysis was performed to correlate the amyloid deposits with vicinal dermal structures. The amyloid class was determined by means of immunocytochemistry. TTR amyloid was primarily localized to lymphatic microvessels in the present case, whereas arterioles were devoid of TTR amyloid deposits. In addition, the well-known association of TTR amyloid with neural structures along the erector pilorum and around the sebaceous and serosal (sweat) glands was also evident. Electron microscopic analysis of amyloid deposits revealed characteristic amyloid fibrils that were irregular in shape, and exhibited a heterogeneous density and a random deposition pattern. Immunocytochemistry confirmed the cutaneous accumulation of TTR amyloid. In conclusion, amyloid deposits were abundantly present in the skin of a patient with "Hungarian-type" TTR amyloidosis; skin biopsy seems to be appropriate for the diagnosis of this disorder. We showed that besides the erector pilorum, sweat glands and nerve terminals, lymphatic microvessels are also severely infiltrated by TTR amyloid. Whether these pathological alterations can exclusively be found in "Hungarian-type" TTR amyloidosis should still be investigated. If such changes are not specific for the Asp18Gly mutation, they may be considered as diagnostic markers for "central" TTR amyloid disorders.     

Immunohistochemical study on the keratin expression in generating rat hair tissues using anti-hair keratin monoclonal antibodies]

To investigate keratin expressions of generating rat hair tissues, monoclonal antibodies, HKN-2, 4, 5 and 6, were immunohistochemically applied on the skin specimens from 19-day-old rat fetus, newborn, 3-day-old and 7-day-old rats. In anagen hair tissues of 7-day-old rats, HKN-2 reacted with developing cells of the medulla, cortex, hair cuticle and inner and outer root sheaths. In the epidermis, HKN-2 reacted with spinous through horny cells. HKN-4 displayed a broad reactivity with all of the skin epithelial cells including hair tissue. These reactions were first seen in hair peg stage. HKN-2 and 4 first showed strong reactions with the innermost cell layer of the outer root sheath in anagen hair tissues of newborn rats. Reactivities by HKN-5 and 6 were localized in hair tissues in rats; however, HKN-5 showed no reaction with the innermost cell layer of the outer root sheath. HKN-5 and 6 showed no reaction with hair tissue before anagen. It is concluded that hair germ is different from epidermal basal cells in keratin expressions, that hair-specific keratins seem to be produced after the morphological differentiation of each layer, and that the innermost cell layer may differ from other outer root sheath since hair generation.     

Nylon brush macular amyloidosis

Long-term use of a nylon brush for back scratching by a 53-year-old white woman was associated with the development of typical macular amyloidosis. EKH4 monoclonal antikeratin antibody, which recognizes 50-kd neutral and acidic keratin species, labeled this amyloid. Confirmation of amyloid substance in the lesion included positive staining with Dylon and thioflavin T; immunohistochemical reactions with monoclonal and polyclonal antibodies against elastic fiber microfibrils (NKH1 and anti-P component), immunoglobulins (IgG, IgM, and IgA), and complement (C3); and electron microscopic identification of 6- to 10-nm straight filaments. Type IV collagen staining demonstrated a breakage and/or thickening of the dermoepidermal basement membrane above the amyloid deposition in the papillary dermis. Electron microscopic findings confirmed this phenomenon.     

Multiple warty dyskeratomas of the scalp

Two patients presented with the unusual condition of multiple warty dyskeratomas on the scalp. Biopsies of affected skin stained positive with human keratin monoclonal antibodies HKN-6 and -7, specific for cortex and inner root sheath of normal human hair, respectively. Multiple warty dyskeratomas are a rare occurrence and their actiopathogenesis remains elusive. Positive immunohistochemical staining of a lesion with antikeratin antibodies HKN-6 and -7, specific for human hair keratin, suggests a follicular origin for warty dyskeratoma.     

Systemic amyloidoses

Amyloidoses are a heterogeneous group of diseases characterized by extracellular fibrillar protein deposits in the organs and tissues. These proteins are not biochemically related to each other, but share certain common characteristics, including apple green birefringence with polarized light after staining with Congo red, and beta-pleated sheet configuration through x-ray diffraction. Amyloid deposits may occur in many organs (systemic amyloidoses) or may affect a single tissue (localized or organ-specific amyloidoses). There are different classifications, but in this review the amyloidoses are organized by clinical symptoms, which are determined by the amyloid protein involved. Special attention is given to cutaneous and mucous membrane manifestations, which are often the first sign of the disease and are useful for early diagnosis, thus avoiding more aggressive procedures. The involvement of other organs is analyzed, as are the diagnosis, prognosis and treatment of systemic amyloidoses.