Polineuropatía por amiloidosis por transtiretina de inicio tardío. Caso clínico / Late-onset hereditary transthyretin amyloidosis with polyneuropathy. Report of one case

Hereditary transthyretin amyloidosis is a multisystemic autosomal dominant genetic disorder characterized by progressive distal sensory-motor polyneuropathy or restrictive cardiomyopathy, secondary to amyloid deposits. Its pathogenesis lies in the TTR gene mutation, and the Val50Met mutation is the most frequent. Patients have significant differences in the onset and severity of clinical presentation according to their country of origin. The diagnosis of this pathology is complex, even more in countries where it is not considered endemic. However, early suspicion and management are essential to improve survival and avoid unnecessary diagnostic and therapeutic strategies. We report a 69-year-old woman who presented a sensory-motor polyneuropathy, predominantly sensory, associated with distal neuropathic pain and bilateral vitritis. The history of her Italian father with polyneuropathy of unspecified etiology stood out. A vitreous biopsy identified amyloid substance deposits (congo red positive). These were also confirmed on a superficial peroneal nerve biopsy. During the etiological study of her polyneuropathy, an increased Kappa/Lambda index of 2.55 mg/L stood out. Therefore, light chain amyloidosis was suspected, and chemotherapy treatment was indicated without favorable response. After 10 years of progressive neurological and ophthalmological involvement, a genetic study confirmed the first case of late-onset hereditary transthyretin amyloidosis Val50Met with polyneuropathy in Chile.

Hidrocistoma apocrino desafío dermatoscópico / Apocrine hydrocystoma dermoscopic challenge

Los hidrocistomas apocrinos son lesiones quísticas benignas. Clínicamente se caracterizan por ser nódulos quísticos claros o traslucidos, solitarios, en forma de cúpula, con superficie lisa. En la mayoría de los casos la localización suele ser alrededor del ojo, particularmente lateral al canto externo. Suelen ser asintomáticos, de crecimiento lento pudiendo llegar a 10 mm de diámetro o más. Presentamos un caso de un paciente con un hidrocistoma apocrino variante pigmentada.

Apocrine hydrocystomas are benign cystic lesions, clinically characterized by being clear or translucent cystic nodules, solitary, domeshaped, with a smooth surface. In most cases the location is usually around the eye, particularly lateral to the outer edge. They are usually asymptomatic, slow growing and can reach 10 mm in diameter or more. We present a case of a patient with a pigmented variant apocrine hydrocystom

Pilomatrixoma proliferante una rara variante histopatológica simulando un carcinoma de células escamosas / Pilomatrixoma proliferating a rare variant histopathological simulating a cell carcinoma scaly

El Pilomatrixoma es un tumor anexial benigno. Presenta una variante histopatológica infrecuente denominada pilomatrixoma proliferante reportada en 1997 por Kaddu et al. Corresponde a una lesión compuesta predominantemente por una proliferación lobular de células basaloides, con atipia nuclear variable y figuras mitóticas, áreas focales que contienen material cornificado eosinófilo, junto con células sombra. Se propuso al pilomatrixoma proliferante como un subconjunto histopatológico distintivo del pilomatrixoma y se consideró como una variante proliferativa con un perfil histopatológico benigno. La dermatoscopía en este tumor, sobre todo en pacientes de edad avanzada, puede llegar a constituir una trampa dermatoscópica, que es difícil de diferenciar de otras lesiones, como el melanoma o el carcinoma de células basales. Existen múltiples reportes de casos en la literatura donde se informa de pilomatrixomas clásicos o proliferantes simulando otras neoplasias. Presentamos el caso de una paciente de 88 años con pilomatrixoma proliferante facial que simuló clínicamente un carcinoma de células escamosas y llevó a confusión diagnóstica inicial, se destacan las características histopatológicas y clínicas de los pilomatrixomas proliferantes.

Pilomatrixoma is a benign adnexal tumor. It has an infrequent histopathological variant called proliferating pilomatrixoma reported in 1997 by Kaddu et al. It corresponds to a lesion composed predominantly by a lobular proliferation of basaloid cells, with variable nuclear atypia and mitotic figures, focal areas containing eosinophilic cornified material, together with shadow cells. The proliferating pilomatrixoma was proposed as a distinctive histopathological subset of the pilomatrixoma and was considered as a proliferative variant with a benign histopathological profile. Dermatoscopy in this tumor, especially in elderly patients, can result in a dermatoscopic trap, which makes it difficult to differentiate from other lesions, such as melanoma or basal cell carcinoma. There are multiple reports of cases in the literature where classic or proliferating pilomatrixomas were reported simulating other neoplasms. We present the case of an 88-year-old patient with a proliferating facial pilomatrixoma that clinically simulated a squamous cell carcinoma and led to an initial diagnostic confusion, highlighting the histopathological and clinical characteristics of the proliferating pilomatrixoma.