Familial amyloidosis of the Finnish type: clinical and neurophysiological features of two index cases.

Familial amyloidosis of the Finnish type (FAF) is a rare multisystemic disorder caused by mutations in the gelsolin gene. The clinical presentation is typically characterised by a triad of ophthalmic, neurological and dermatological findings. FAF has been reported in several countries, primarily in Finland and recently in Portugal. We report the first genetically confirmed cases of FAF from two unrelated families in our neuromuscular outpatient clinic. Gelsolin gene sequencing revealed the heterozygous gelsolin mutation (c.640G>A). The clinical features and the neurophysiological studies of two index patients and their relatives are presented. Obtaining an early diagnosis can be challenging, but FAF should be considered in the differential diagnosis of progressive bilateral facial neuropathy, even if there is no known Finnish ancestor.

A unique case of concurrent cutaneous lichen amyloidosis and myxedema.

Lichen amyloidosis is believed to be caused by damage to keratinocytes, often by chronic scratching. It has also been associated with autoimmune conditions, including thyroid disease. Dermatologic manifestations of poorly controlled thyroid disease are well described within the medical literature, within both hypothyroid and hyperthyroid states. Myxedema is a rare complication of Graves disease. We report a unique case of concurrent myxedema and lichen amyloidosis in a 63-year-old patient with uncontrolled hypothyroidism in the setting of post-ablative Graves disease.

Diagnóstico clínico y genético de un caso de síndrome de Meretoja e intervención mediante lifting frontotemporal / Clinical and genetical diagnosis of a case of Meretoja syndrome and frontotemporal lifting procedure

Un varón de 56 años con antecedentes familiares de distrofia corneal consulta por mala visión subjetiva. La biomicroscopia revela una distrofia estromal reticular bilateral y la inspección facial muestra signos de disfunción muscular, como ptosis de cejas, debilidad y descolgamiento de la musculatura frontal, piel redundante en la frente e hiperelasticidad cutánea. El paciente es remitido a cirugía plástica para valoración de la afectación muscular frontal, siendo intervenido mediante lifting frontotemporal. Por otro lado, se realiza estudio genético que confirma la variante patogénica c.640G>A (p.Asp214Asn) en el gen GSN, que codifica la gelsolina, mutación asociada con la amiloidosis familiar tipo finlandés o síndrome de Meretoja (AU)

A 56-year-old male with family background of corneal dystrophy presents with poor subjective vision. Biomicroscopy reveals bilateral reticular stromal dystrophy and facial inspection shows signs of muscle dysfunction, such as eyebrow ptosis, weakness and sagging of the frontal muscles, redundant skin on the forehead and skin hyperelasticity. The patient is referred to plastic surgery for evaluation of the frontal muscle involvement, undergoing a frontotemporal lifting procedure. On the other hand, genetics confirms the pathogenic variant c.640G>A (p.Asp214Asn) in the GSN gene, encoding gelsolin, a mutation associated with Finnish-type familial amyloidosis or Meretoja syndrome (AU)

Primary Localized Cutaneous Amyloidosis Secondary to Sand Rubbing in a Wrestler.

A 40-year-old male, wrestler since 15 years of age presented with asymptomatic hyperpigmentation over both his both upper extremities for 10 years. There was no history of preceding itching or redness; of using a nylon brush, scrubbers, or sponges during bathing; or of excessive towel rubbing after bathing and applying cosmetics; however, he had been rubbing sand over both arms for 15 years. He had no personal or family history of atopy, diabetes, or thyroid disease. Cutaneous examination revealed the presence of symmetrical sharply defined reticulate brownish hyperpigmentation over both arms and favoring the left (Figure 1). Dermatoscopy revealed multiple uniform small brown fine streaks radiating from the center becoming reticulated (Figure 2). Hematologic and biochemical studies, in particular thyroid studies, were normal. Histopathologic examination revealed an amorphous eosinophilic deposit in the papillary dermis suggestive of macular amyloidosis (MA) (Figure 3). Methyl violet stain revealed amyloid positive areas (Figure 4), and a diagnosis of MA was made. With the cessation of the sand rubbing and the application of tacrolimus ointment (0.1%), the lesions slowly diminished. (SKINmed. 2022;20:141-143).

The experience of hereditary apolipoprotein A-I amyloidosis at the UK National Amyloidosis Centre.

INTRODUCTION: Hereditary apolipoprotein A-I (AApoAI) amyloidosis is a rare heterogeneous disease with variable age of onset and organ involvement. There are few series detailing the natural history and outcomes of solid organ transplantation across a range of causative APOA1 gene mutations. METHODS: We identified all patients with AApoAI amyloidosis who presented to the National Amyloidosis Centre (NAC) between 1986 and 2019. RESULTS: In total, 57 patients with 14 different APOA1 mutations were identified including 18 patients who underwent renal transplantation (5 combined liver-kidney (LKT) and 2 combined heart-kidney (HKT) transplants). Median age of presentation was 43 years and median time from presentation to referral was 3 (0-31 years). Involvement of the kidneys, liver and heart by amyloid was detected in 81%, 67% and 28% of patients, respectively. Renal amyloidosis was universal in association with the most commonly identified variant (Gly26Arg, n = 28). Across all variants, patients with renal amyloidosis had a median creatinine of 159 µmol/L and median urinary protein of 0.3 g/24 h at the time of diagnosis of AApoAI amyloidosis and median time from diagnosis to end-stage renal disease was 15.0 (95% CI: 10.0-20.0) years. Post-renal transplantation, median allograft survival was 22.0 (13.0-31.0) years. There was one early death following transplantation (infection-related at 2 months post-renal transplant) and no episodes of early rejection leading to graft failure. Liver transplantation led to regression of amyloid in all four cases in whom serial 123I-SAP scintigraphy was performed. CONCLUSIONS: AApoAI amyloidosis is a slowly progressive disease that is challenging to diagnose. The outcomes of transplantation are encouraging and graft survival is excellent.

Estudio descriptivo de la amiloidosis por transtiretina en un hospital de tercer nivel sin unidad de referencia / A descriptive study of transthyretin amyloidosis in a tertiary hospital without a referral unit

Antecedentes y objetivo: La amiloidosis por transtiretina (ATTR) es una enfermedad rara que forma parte de las amiloidosis sistémicas, y es una enfermedad amenazante para la vida. Puede afectar a todos los órganos y sistemas, siendo la más frecuente la afectación neurológica y cardíaca. El objetivo de este estudio es detectar posibles casos de ATTR y realizar un estudio descriptivo de los mismos. Material y métodos: Estudio descriptivo unicéntrico realizado en un hospital de tercer nivel en el que se incluyen pacientes con sospecha de ATTR entre septiembre de 2016 y enero de 2020. Resultados: Se detectan 190 pacientes sospechosos de ATTR. En el estudio se incluyen 100 de ellos, así como 10 familiares de pacientes en los que se detecta ATTR en su variante genética. En total, se detecta ATTR variante genética en 7 individuos (3 con mutación presintomática de la enfermedad), 16 pacientes con ATTR asociada a la edad y 31 individuos con amiloidosis cardíaca no filiada con las pruebas realizadas, lo que confirma la presencia de esta enfermedad en áreas no endémicas. Conclusiones: La ATTR es una enfermedad que se ha de tener en cuenta en el diagnóstico diferencial de pacientes que presentan insuficiencia cardíaca con FEVI preservada, principalmente si se asocia a síntomas neurológicos (AU)

Background and objective: Transthyretin amyloidosis (ATTR) is a rare disease that is part of systemic amyloidosis and is life-threatening. It can affect all organs and systems, the most frequent being neurological and cardiac involvement. This study aims to detect possible ATTR cases and carry out a descriptive study of them. Material and methods: Descriptive single-centre study carried out in a tertiary hospital, which included patients with suspected ATTR between September 2016 and January 2020. Results: A total of 190 suspected ATTR patients were detected. The study includes 100 of these patients, as well as 10 relatives of patients in whom ATTR was detected in its genetic variant (ATTRv). In total, ATTRv was detected in 7 individuals (3 with a presymptomatic mutation of the disease), 16 patients with age-related ATTR and 31 individuals with unknown cardiac amyloidosis with the tests performed, which confirms the presence of this disease in non-endemic areas. Conclusions: ATTR is a disease that must be taken into account in the differential diagnosis of patients with heart failure with preserved LVEF, especially if associated with neurological symptoms (AU)

C4d as a Practical Marker for Cutaneous Amyloidosis.

ABSTRACT: Cutaneous amyloidosis (CA) is defined by the accumulation of amyloid in the dermis; it might be primary or secondary. The diagnosis is based on histopathological findings with the demonstration of amyloid deposits, confirmed by Congo red stain under the polarized light. Studies on other diagnostic markers are ongoing in the literature. The aim of this study was to demonstrate the utility of C4d staining in the recognition of amyloid in CA and using it as an alternative or substitute marker for the diagnosis. In this retrospective study, 199 skin biopsies with a clinical provisional diagnosis of CA were analyzed, the Congo red stain was performed, and, in a subgroup (n = 97) with histopathological findings probably for CA, C4d immunohistochemistry was assessed. Forty-eight cases of CA were detected. Congo red birefringence was positive in all cases, whereas in 14 cases, it was faded. In these 14 cases, the diagnosis of CA was made by means of Congo red fluorescence and Thioflavin T because the histopathological findings were highly suggestive for CA. All CA cases were positive with C4d, and in 12 of the 49 inflammatory dermatoses, C4d was positive. The interpretation of C4d immunohistochemistry can be performed more easily and rapidly than Congo red evaluation. The sensitivity and specificity of C4d were 100% and 75.5%, respectively. In our experience, C4d staining was a useful method for detecting amyloid deposits in CA. Although Congo red staining is the gold standard for amyloid detection, we propose C4d immunohistochemistry as a routine screening method or hybrid transition while further investigations are completed.

AL Lambda Amyloidosis Activates Acute Liver Failure in the Absence of Plasma Cell Dyscrasia.

A patient with systemic amyloidosis developed portal hypertension, acute liver failure and multiorgan dysfunction. Extensive testing was unrevealing for paraproteinemia, plasma cell dyscrasia, infectious, or inflammatory conditions. He was transferred to our institution for orthotopic liver transplant evaluation but was ultimately declined given clinical instability and dysautonomia. Post-mortem evaluation revealed extensive amyloid deposition in multiple organs determined to be AL-lambda amyloidosis.

Amyloidosis cutis dyschromica cases caused by GPNMB mutations with different inheritance patterns.

BACKGROUND: Amyloidosis cutis dyschromica (ACD) is a rare form of primary cutaneous amyloidosis featured by reticulate dotted hypo- and hyperpigmentation. Recently, loss-of-function mutations in GPNMB, encoding glycoprotein (transmembrane) nonmetastatic melanoma protein B, were found in autosomal-recessive or semi-dominant ACD. OBJECTIVE: This study aims to detect the genetic defect underlying ACD in nine separate cases and to investigate the functional consequences of the mutants. METHODS: Nine ACD cases were collected including eight with autosomal-recessive pattern and one with autosomal-dominant pattern. Whole-exome sequencing or Sanger sequencing of the GPNMB gene was performed to detect the pathogenic mutations. Haplotype analysis was employed to determine the origin of mutation c.565C > T using adjacent highly polymorphic SNPs. Immunoblotting and subcellular localization assessments were performed to evaluate the expression of the mutants using HEK293 cells transfected with the GPNMB constructs. RESULTS: We detected four recurrent mutations (c.393 T > G, p.Y131*; c.565C > T, p.R189*; c.1056delT, p.P353Lfs*20; c.1238 G > C, p.C413S) and two novel mutations (c.935delA, p.N312Tfs*4; c.969 T > A, p.C323*) in GPNMB. Mutation c.565C > T found in six separate ACD cases shared a common haplotype. The two novel mutations caused a decreased abundance of truncated proteins. The c.1238 G > C mutation, which was detected in the autosomal-dominant case, caused abnormal reticular subcellular localization of the protein. A major percentage of wildtype changed its expression pattern when co-expressed with this mutant. CONCLUSIONS: Our findings proved that the recurrent mutation c.565C > T originated from a founder effect. The autosomal-dominant ACD associated mutation p.C413S played its pathogenic role through a dominant-negative effect on wild-type GPNMB. This study expands the genotype and inherited modes of ACD and improves our understanding of the pathogenesis of this disorder.

Ocular Involvement in Hereditary Amyloidosis.

The term amyloidosis describes a group of rare diseases caused by protein conformation abnormalities resulting in extracellular deposition and accumulation of insoluble fibrillar aggregates. So far, 36 amyloid precursor proteins have been identified, and each one is responsible for a specific disease entity. Transthyretin amyloidosis (ATTRv) is one of the most common forms of systemic and ocular amyloidosis, due to the deposition of transthyretin (TTR), which is a transport protein mainly synthesized in the liver but also in the retinal pigment epithelial cells. ATTRv amyloidosis may be misdiagnosed with several other conditions, resulting in a significant diagnostic delay. Gelsolin and keratoepithelin are other proteins that, when mutated, are responsible for a systemic amyloid disease with significant ocular manifestations that not infrequently appear before systemic involvement. The main signs of ocular amyloid deposition are in the cornea, irido-corneal angle and vitreous, causing complications related to vasculopathy and neuropathy at the local level. This review aims at describing the main biochemical, histopathological and clinical features of systemic amyloidosis associated with eye involvement, with particular emphasis on the inherited forms. We discuss currently available treatments, focusing on ocular involvement and specific ophthalmologic management and highlighting the importance of a prompt treatment for the potential sight-threatening complications derived from amyloid deposition in ocular tissues.

Primary cutaneous amyloidosis: A clinicopathological, histochemical, and immunohistochemical study.

BACKGROUND: Primary cutaneous amyloidosis (PCA) comprises several forms of localized cutaneous amyloidosis characterized by amyloid deposits occurring at or near dermal-epidermal junctions. Immunohistochemical studies have shown the expression of cytokeratin (CK) suggesting that it has an epidermal origin. OBJECTIVES: To study the clinicopathological features of PCA and expression of CK5/6 and correlate it with Congo red stain. MATERIALS AND METHODS: A total of 30 histologically proven cases of PCA were studied. Congo red staining and immunohistochemical expression of CK5/6 were analyzed. STATISTICAL ANALYSIS: : The qualitative data has been expressed as proportions and the quantitative data has been expressed as mean ± SD. All data was analyzed using the Statistical Package for Social Sciences (SPSS) software version 22. RESULTS: Deposits of amyloid in papillary dermis were seen in all 30 cases. Mild focal basal cell vacuolar degeneration and apoptotic bodies in epidermis were seen in six cases. The presence of pigment cells in dermis were seen in 26 cases. CK5/6 showed weak/mild immunopositivity in nine cases, moderate in 20 cases, and strong in one case. CONCLUSION: The presence of dermal melanophages interspersed within eosinophilic deposits gives a clue to the diagnosis. Congo red stain highlights the deposits and visualization under polarized light gives apple green birefringence which is diagnostic of amyloid. Staining of amyloid deposits by CK5/6 proves that the amyloid is of keratinocyte origin. There was 100% sensitivity with Congo red and CK5/6. Thus, CK5/6 can be used as an adjunct tool to Congo red stain in the diagnosis of primary cutaneous amyloidosis.

Hereditary Apolipoprotein A-1 Amyloidosis With Glu34Lys Mutation Treated by Liver Transplantation: A Case Report.

Hereditary apolipoprotein A-1 (ApoA-1) amyloidosis is a rare disease characterized by progressive deposition of amyloid fibrils in the kidney, heart, and liver. We observed a 45-year-old male patient with liver failure. Liver dysfunction was detected at 30 years of age during an annual health check-up. At 35 years of age, renal dysfunction was also found. At 40 years of age, the pathologic findings of the liver revealed amyloid deposition. A testis biopsy specimen taken at 42 years of age to identify the cause of male infertility showed amyloid accumulation. At 43 years of age, the amyloid results and genetic profile led to a definitive diagnosis of hereditary ApoA-1 amyloidosis caused by Glu34Lys mutation. A family history was absent. Liver failure showed Budd-Chiari-like formation, including enlargement of the caudate lobe and liver congestion. Although the patient showed end-stage liver cirrhosis and renal failure, only liver transplant was performed considering the burden for a living donor. The enlarged liver (4.9 kg) showed amyloid deposition in parenchyma and the space of Disse. Amyloid also accumulated in the giant spleen. The APOA1 mutation Glu34Lys is extremely rare, and in this case hepatic failure was successfully treated by liver transplant to both replace organ function and reduce production of the amyloidogenic ApoA-1-variant protein. Careful observation for reaccumulation of amyloidosis in the organ is required.