Nefropatía IgA en Uruguay: presentación clínica y evolución / IgA Nephropathy in Uruguay: clinical presentation and evolution

La nefropatía IgA es frecuente en Uruguay y su tratamiento conflictivo. Objetivo: analizar la incidencia, presentación clínica, histología, tratamiento y evolución de la nefropatía IgA en Uruguay. Material y método: se realizó un análisis retrospectivo de datos del Registro Uruguayo de Glomerulopatías (RUG) e historias clínicas con estricta confidencialidad; se registró edad, sexo, fecha de biopsia renal, presentación clínica, presión arterial (PA), proteinuria, hematuria y creatininemia (al inicio y en última evolución registrada), histología, tratamientos y evolución. Análisis estadístico uni y multivariado. Aprobado por el Comité de Ética del Hospital de Clínicas. Resultados: se estudiaron 341 pacientes con nefropatía IgA, confirmada por histología, en el período comprendido entre el 1º de enero de 1985 y el 31 de diciembre de 2009; 65% hombres, edad media 31 ± 13 años y mediana de seguimiento de 52 meses (1-271); 14% ingresaron a diálisis y 1,2% fallecieron. La presentación clínica más frecuente fue con alteraciones urinarias asintomáticas (AUA) (42%), (mayor en el período 2000-2009, chi2 p < 0,05). Al inicio, la proteinuria era 1,7 ± 1,9 g/l; creatininemia 1,6 ± 1,8 mg/dl, y 32% tenían PA ≥ 140/90 mmHg. Se observaron semilunas en 48%. Recibieron inhibidores de la enzima convertidora de angiotensina/antagonistas de los receptores de la angiotensina II (IECA/ARAII) 56% e inmunosupresores, 52%. La PA disminuyó significativamente en la evolución. En el análisis univariado, la creatininemia inicial fue ≥ 2,5 mg/dl, proteinuria, semilunas y proliferación endocapilar se asociaron a ingreso a diálisis o fallecimiento, pero en el análisis multivariado (regresión de Cox) solo fue significativo el nivel de creatininemia. Conclusiones: la presentación clínica de nefropatía IgA ha cambiado en la última década, siendo más frecuente las AUA. La creatininemia ≥ 2,5 mg/dl se asocia a peor supervivencia renal, probable “punto de no retorno”...

IgA nephropathy is a frequent condition in Uruguay and treating it is controversial.Objective: to analyse incidence, clinical presentation, histology, treatment and evolution of nephropathy in Uruguay.Method: we conducted a retrospective study of data kept at the Uruguayan Registry of Glomerulopathies and medical records under strict confidentiality. Age, sex, date of the kidney biopsy, clinical presentation, blood pressure, proteinuria, hematuria and creatininemia (initial and in the last evolution recorded), histology, treatment and evolution were registered. Single-variate and multivariate statistic analysis were applied. The study was approved by the Ethics Committee of the Clínicas University Hospital.Results: Three hundred and forty one patients with IgA nephropathy – confirmed with histopathology analysis - were studied. Sixty five per cent were men, average age was 31 ± 13 year old and follow-up median 52 months (1-271); 14% started with dialysis and 1.2% died. The most common clinical presentation was asymptomatic urinary alterations (42%), (and this was more evident in the 2000-2009 period, chi2 p < 0.05). At the beginning, proteinuria was 1.7 ± 1.9 g/l; creatininemia 1.6 ± 1.8 mg/dl, and blood pressure was PA ≥ 140/90 mmHg in 32% of patients. Crescent formations were observed in 48%. Fifty six per cent of them received angiotensin-converting enzyme (ACE) / angiotensin receptor blockers and 52% of patients received immunosuppressants. Blood pressure significantly dropped in the evolution. In the single-variate analysis, initial creatininemia was ≥ 2.5 mg/dl, proteinuria, crescent formations and endocapillary proliferation were associated to starting dialysis or death, although in the multivariate analysis (Cox regression) only the level of creatininemia was significant.Conclusions: the clinical presentation of IgA nephropathy has changed in the past decade, being the asymtomatic urinary alterations the most frequent...

A nefropatia IgA é frequente no Uruguai e seu tratamento conflitivo.Objetivo: analisar a incidência, apresentação clínica, histologia, tratamento e evolução da nefropatia IgA no Uruguai.Material e método: uma análise retrospectiva dos dados do Registro Uruguaio de Glomerulopatias (RUG) e prontuários médicos com absoluta confidencialidade foi realizada; foram registrados idade, sexo, data da biopsia renal, apresentação clínica, pressão arterial (PA), proteinúria, hematúria e creatininemia (no inicio e na última evolução registrada), histologia, tratamentos e evolução. Análise estatística uni e multivariada. Aprovado pelo Comitê de Ética do Hospital das Clínicas.Resultados: foram estudados 341 pacientes com nefropatia IgA, confirmada por histologia, no período 1º de janeiro de 1985 - 31 de dezembro de 2009; 65% eram homens, idade média 31 ± 13 anos e mediana de seguimento de 52 meses (1-271); 14% ingressaram a diálise e 1,2% faleceu. A apresentação clínica mais frequente foi presença de alterações urinárias assintomáticas (AUA) (42%), (maior no período 2000-2009, chi2 p < 0,05). No inicio, a proteinuria era 1,7 ± 1,9 g/l; creatininemia 1,6 ± 1,8 mg/dl, e 32% apresentaram PA ≥ 140/90 mmHg. Foram observadas crescentes celulares em 48%. Receberam inibidores da enzima conversora da angiotensina/antagonistas dos receptores da angiotensina (IECA/ ARA) 56% e imunossupressores, 52%. A PA diminuiu significativamente na evolução. Na análise univariada, a creatininemia inicial foi ≥2,5 mg/dl, proteinúria, crescentes celulares e proliferação endocapilar estavam associados ao ingresso à diálise e ao falecimento, porém na análise multivariada (regressão de Cox) somente o nível de creatininemia foi significativo.Conclusões: a apresentação clínica da nefropatía IgA mostrou mudanças na última década, sendo mais frequente as AUA. A creatininemia ≥ 2,5 mg/dl está associada a pior supervivência renal, provável “ponto de não retorno”...

Post-implant evaluation of the anastomotic mechanical and geometrical coupling between human native arteries and arterial cryografts implanted in lower-limb: mechanical, histological and ultraestructural studies of implanted cryografts.

BACKGROUND: There is an urgent need of vascular substitutes (VS) to be used in lower limb revascularization procedures when autologous veins are not available and synthetic prosthesis are contraindicated. Since the mechanical differences with respect to native vessels are determinants of the VS failure, the substitutes should have mechanical properties similar to those of the recipient vessels. The use of cryopreserved arteries (cryografts) could overcome limitations of available VS. These work aims were to characterize (a) native vessels/implanted cryografts mechanical and geometrical coupling, (b) cryografts capability to ensure mismatch levels lesser than those expected for expanded polytetrafluoroethylene (ePTFE), (c) cryografts functional properties considering their histological and ultra-structural characteristics. METHODS: Instantaneous pressure (mechano-transducers) and diameter (B-mode echography) were obtained in implanted femoro-popliteal, ileo-femoro-popliteal and axilo-humeral cryografts (n=8), in femoral arteries from recipients (n=8), recipient-like (n=15) and multiorgan donors-like (n=15) subjects, and in ePTFE segments (n=10). Calculus: (a) Mechanical parameters: elastic modulus, arterial compliance, distensibility and characteristic impedance; (b) Arterial remodeling: diameter, wall thickness, cross-sectional area and wall-to-lumen ratio; (c) Native vessels/VS coupling. Histological and structural analysis were done in explanted femoro-popliteal and axilo-humeral cryografts (n=7). RESULTS: Post-implant the cryografts remodeled. Their stiffness increased and the conduit function diminished. Remodeling resulted in an improvement in native vessels/cryograft coupling, which was always better than native vessels/ePTFE coupling. CONCLUSIONS: Post-implant cryograft remodeling improved native vessels/cryografts coupling. Cryografts would have mechanical and geometrical advantages over ePTFE. Anastomotic cryograft remodeling differed from that expected only due to haemodynamic factors. The structural properties of the remodeled cryografts contribute to explain their functional characteristics.

Novel ancestral Dysferlin splicing mutation which migrated from the Iberian peninsula to South America.

Primary dysferlinopathies are a group of recessive heterogeneous muscular dystrophies. The most common clinical presentations are Miyoshi myopathy and LGMD2B. Additional presentations range from isolated hyperCKemia to severe functional disability. Symptomatology begins in the posterior muscle compartment of the calf and its clinical course progresses slowly in Miyoshi myopathy whereas LGMD2B involves predominantly the proximal muscles of the lower limbs. The age of onset ranges from 13 to 60years in Caucasians. We present five patients that carry a novel mutation in the exon12/intron12 boundary: c.1180_1180+7delAGTGCGTG (r.1054_1284del). We provide evidence of a founder effect due to a common ancestral origin of this mutation, detected in heterozygosity in four patients and in homozygosity in one patient.

Desmin myopathy with severe cardiomyopathy in a Uruguayan family due to a codon deletion in a new location within the desmin 1A rod domain.

Desmin myopathy is a heterogeneous neuromuscular disorder characterized by skeletal myopathy and cardiomyopathy, inherited mostly in an autosomal dominant pattern. We report a five generation Uruguayan family with severe cardiomyopathy and skeletal myopathy. Its most striking features are: atrial dilation, arrhythmia, conduction block and sudden death due to conduction impairment. Affected skeletal muscle shows alteration of mitochondria with paracrystallin inclusions and granulofilamentous material scattered in the muscle fibres. This family carries an unusual deletion p.E114del within the 1A rod domain of desmin. Transfected cells expressing the mutated desmin show punctuated and speckled cytoplasmic aggregates. The mutation causes a local conformational change in heptads a/d residues and charge positions. These findings lead to the hypothesis that coiled-coil interactions may be impaired, resulting in severe alterations in the desmin network. This is the first time that a mutation affecting this domain in the desmin molecule is described in a desminopathy.

Nefropatía C1q en un paciente de 17 años: caso clínico / C1q nephropathy: report ofone case

Clq nephropathy (Clq N) is an infrequent disease and only about 100 cases have been reponed. It is defined by a pattern of immunofluorescense (IF) with dominant or co-dominant complement Clq with electrondense deposits in the mesangium, without clinical or serological features of Lupus Nephritis. The most common histopathological findings of ClqN are focal segmental glomerulosclerosis and Minimal Change Disease. We repon a 17 year-old male patient with an isolated selective proteinuría found in a routine study. He had normal renal function and uriñe culture was negative. Serum lipids, liver enzymes an complement were all normal. Serum antinuclear and anti-DNA antibodies, antineutrophil cytoplasmic antibodies (ANCA), HIV, Hepatitis B and C serology, were negative. Renal and abdominal ultrasonography was normal. The histopathological study revealed segmental glomerular sderosis, modérate increase of mesangial matrix, Bowmann capsule adhesions and fucsinophil deposits in mesangium. The IF was positive (dominant) for Clq (+++) and IgA, IgG, IgM, C3++, all of them with a granular mesangial distribution. Ultrastructural findings were pedicelar effacement and paramesangial electrondense deposits. Tubular reticular inclusions (TRI) were not found. Remission of proteinuría was reached after 18 months of treatment with enalapril and losartan. The patient remains with normal renal function. Clinical findings, negative serology for Lupus, light microscopy IFwith dominant positivity for Clq, absence of TRI and paramesangial electrondense deposits in electron microscopy lead us to the diagnosis of ClqN. A poor response to steroid therapy was described in ClqN. Thus it was worthwhile to differentiate it from lupus nephritis, that is responsive to steroids.

CADASIL: comunicación de una familiauruguaya con definición clínica, imagenológica, anatomopatológica y genética molecular / Clinical, imagenology, anatomopathological and molecular genetics results for the diagnosis of CADASIL in a Uruguayan family

Introducción: el síndrome CADASIL (Cerebral Dominant Arteriopathy with Subcortical Infarcts and Leukoencephlopathy) es una microangiopatía no amiloidea, no ateromatosa que se transmite en forma autosómica dominante y cuyas principales manifestaciones clínicasocurren a nivel cerebral. Su diagnóstico requiere criterios clínicos, imagenológicos y genéticos moleculares.Material y método: se estudiaron anatomopatológicamente mediante biopsia de piel y músculo y estudio genético molecular a tres integrantes de una familia con diagnóstico de CADASIL.Resultados: los exámenes clínicos, paraclínicos, neurológicos y ultraestructural de biopsia de piel mostraron resultados consistentes con CADASIL. La secuenciación de exones 2,3,4,5,8,11,20,23 del gene NOTCH3 detectó una mutación en forma heterocigota en el exón 5 no descripta en la literatura.Conclusiones: destacamos la importancia del diagnóstico precoz de esta enfermedad y la definición molecular que permite el asesoramiento genético a todos los integrantes de lafamilia y, eventualmente, el diagnóstico prenatal.

Introduction: CADASIL syndrome (Cerebral Dominant Arteriopathy with Subcortical Infarcts and Leukoencephlopathy),the most common form of hereditary stroke disorder is a nonamyloid, non-atheromatous microangiopathy. Main clinical features are found in the brain. The disease may be diagnosed by clinical findings, images and geneticmolecular criteria.Methods: an anatomopathological analysis through a skin and muscle biopsy and molecular study was performed on three members of the same family diagnosed with CADASIL.Results: clinical, paraclinical, neurological and ultrastructuralskin biopsy study's findings were consistent with CADASIL. NOTCH3 sequence exonal analysis(2,3,4,5,8,11,20,23) suggested heterocigotic mutations in exon 5, not previously described in literature.Conclusions: we stress the importance of early diagnosis of this disease and the molecular definition that enablesgenetic counselling to all members of the family and, potentially, prenatal diagnosis of the disease.

Introdução: a síndrome CADASIL (Cerebral Dominant Arteriopathy with Subcortical Infarcts and Leukoencephlopathy)é uma microangiopatia não amiloidea, não ateromatosa que se transmite de maneira autossômica dominantecujas principais manifestações clinicas são observadas no cérebro. Para seu diagnóstico é necessário realizarprovas clínicas, imagenológicas e de genética molecular.Material e método: foram realizados exames de anatomia patológica e de genética molecular em biopsias depele e músculo a três integrantes de uma família com diagnóstico de CADASIL.Resultados: os exames clínicos, paraclínicos, neurológicos e ultra-estrutural da biopsia de pele mostraram resultados consistentes com CADASIL. A seqüenciação dos exons 2,3,4,5,8,11,20,23 do gene NOTCH3 detectou uma mutação em forma heterozigótica no exon 5 não descritana literatura.Conclusões: destacamos a importância do diagnóstico precoce desta doença e a definição molecular que permite o assessoramento genético a todos os integrantes da família e, eventualmente, o diagnóstico pré-natal.

[C1q nephropathy. Report of one case]. / Nefropatía C1q en un paciente de 17 años. Caso clínico.

Clq nephropathy (Clq N) is an infrequent disease and only about 100 cases have been reported. It is defined by a pattern of immunofluorescence (IF) with dominant or co-dominant complement Clq with electron-dense deposits in the mesangium, without clinical or serological features of Lupus Nephritis. The most common histopathological findings of ClqN are focal segmental glomerulosclerosis and Minimal Change Disease. We report a 17 year-old male patient with an isolated selective proteinuria found in a routine study. He had normal renal function and urine culture was negative. Serum lipids, liver enzymes an complement were all normal. Serum antinuclear and anti-DNA antibodies, antineutrophil cytoplasmic antibodies (ANCA), HIV, Hepatitis B and C serology, were negative. Renal and abdominal ultrasonography was normal. The histopathological study revealed segmental glomerular sclerosis, moderate increase of mesangial matrix, Bowmann capsule adhesions and fucsinophil deposits in mesangium. The IF was positive (dominant) for Clq (+++) and IgA, IgG, IgM, C3++, all of them with a granular mesangial distribution. Ultrastructural findings were pedicelar effacement and paramesangial electron-dense deposits. Tubular reticular inclusions (TRI) were not found. Remission of proteinuria was reached after 18 months of treatment with enalapril and losartan. The patient remains with normal renal function. Clinical findings, negative serology for Lupus, light microscopy IF with dominant positivity for Clq, absence of TRI and paramesangial electron-dense deposits in electron microscopy lead us to the diagnosis of ClqN. A poor response to steroid therapy was described in ClqN. Thus it was worthwhile to differentiate it from lupus nephritis, that is responsive to steroids.

Poiquilodermia acroqueratótica hereditaria (Weary): enfermedad inmunológica. Ubicación nosológica en una clasificación de las poiquilodermis ampollares hereditarias. Presentación de un caso con estudio inmunológico y ultraestructural / Acrokeratotic hereditary poikiloderma

Se realiza una revisión bibliográfica de casos de poiquilodermia Acroqueratótica Hereditaria o enfermedad de Weary (EW). Hemos concluido que dicha denominación pareciera ser usada en cuatro diferentes cuadros dermatológicos: 1) Enfermedad de Weary Acroqueratótica Hereditaria con herencia familiar autosómica dominante (EW-d); 2) Enfermedad de Weary, con herencia familiar autosómica recesiva y algunos rasgos clínicos de una EW-d asociada a manifestaciones de fotosensibilidad de un síndrome de Kindler; 3) Síndrome de Kindler-Weary (SK-W) con lesiones clínicas de un síndrome de Kindler (poliquilodermia con ampollas traumáticas y atrofia cutánea progresiva) e histopatológicas con manifestaciones liquenoides y presencia de "cuerpos citoides" de una EW-d y 4) Síndrome de Weary-Kindler con manifestaciones de una Poiquilodermia Esclerosante Hereditaria de Weary (HSP), asociada también a manifestaciones ampollares de un SK-r (WE-KS-r). Nosotros relatamos un nuevo caso clínico e histopatológico de una EW-d con presencia de "cuerpos citoides", como expresión de una reacción inmunológica mediada por células, demostrable por inmunohistoquímica. En el diagnóstico diferencial se destaca la distinta patogenia del SK que presenta una malformación displásica genética de la membrana basal electrónica (láminas lúcida y densa) y del tejido conectivo papilar dérmico con desaparición de las fibras elásticas. Nuestra revisión bibliográfica demostró que la EW-d y el SK-r representan dos "formas polares" patogénicas: una predominantemente inmunológica y la segunda malformativa displásica genética, en un amplio espectro de Poiquilodermias Ampollares Hereditarias (HAP), vinculadas con otras cuatro "formas subpolares": EW-r, SK-r, WE-KS-r y SK-d. Estas conclusiones están basadas en el análisis patogénico, clínico, histopatológico, inmunohistoquímico y ultraestructural de componentes del HAP (AU)

Poiquilodermia acroqueratótica hereditaria (Weary): enfermedad inmunológica. Ubicación nosológica en una clasificación de las poiquilodermis ampollares hereditarias. Presentación de un caso con estudio inmunológico y ultraestructural / Acrokeratotic hereditary poikiloderma

Se realiza una revisión bibliográfica de casos de poiquilodermia Acroqueratótica Hereditaria o enfermedad de Weary (EW). Hemos concluido que dicha denominación pareciera ser usada en cuatro diferentes cuadros dermatológicos: 1) Enfermedad de Weary Acroqueratótica Hereditaria con herencia familiar autosómica dominante (EW-d); 2) Enfermedad de Weary, con herencia familiar autosómica recesiva y algunos rasgos clínicos de una EW-d asociada a manifestaciones de fotosensibilidad de un síndrome de Kindler; 3) Síndrome de Kindler-Weary (SK-W) con lesiones clínicas de un síndrome de Kindler (poliquilodermia con ampollas traumáticas y atrofia cutánea progresiva) e histopatológicas con manifestaciones liquenoides y presencia de "cuerpos citoides" de una EW-d y 4) Síndrome de Weary-Kindler con manifestaciones de una Poiquilodermia Esclerosante Hereditaria de Weary (HSP), asociada también a manifestaciones ampollares de un SK-r (WE-KS-r). Nosotros relatamos un nuevo caso clínico e histopatológico de una EW-d con presencia de "cuerpos citoides", como expresión de una reacción inmunológica mediada por células, demostrable por inmunohistoquímica. En el diagnóstico diferencial se destaca la distinta patogenia del SK que presenta una malformación displásica genética de la membrana basal electrónica (láminas lúcida y densa) y del tejido conectivo papilar dérmico con desaparición de las fibras elásticas. Nuestra revisión bibliográfica demostró que la EW-d y el SK-r representan dos "formas polares" patogénicas: una predominantemente inmunológica y la segunda malformativa displásica genética, en un amplio espectro de Poiquilodermias Ampollares Hereditarias (HAP), vinculadas con otras cuatro "formas subpolares": EW-r, SK-r, WE-KS-r y SK-d. Estas conclusiones están basadas en el análisis patogénico, clínico, histopatológico, inmunohistoquímico y ultraestructural de componentes del HAP

Immunohistochemical study of nerve fibres in basal cell carcinoma.

Few studies have been made about the influence of the autonomous nervous system on the proliferation of malignant cells. The aim of this work was to investigate if there is any relationship between the aggressiveness of basal cell carcinoma (BCC) and the presence of nerve fibres. We studied 20 samples of BCC, classified in two groups: non aggressive and aggressive, according to current criteria of malignancy. We used anti-neurofilament (NF) monoclonal antibody and anti-tyrosine hydroxylase (TH) polyclonal antibody, in order to make immunohistochemical detection of nerve fibres and adrenergic fibres respectively. We performed a semi-quantitative score of the results. Our findings showed the existence of statistically significant differences between both groups studied. The largest number of nerve fibres were found in the less aggressive group, whereas they disappeared in infiltrating aggressive proliferations, independently of the histological pattern.

Ultrastructural studies in stable vitiligo.

Vitiligo is a disease of melanocytes characterized by achromic lesions in the skin, affecting the epidermis and the pilosebaceous follicle. We performed an ultrastructural analysis of biopsy specimens from four patients with noninflammatory, stable vitiligo of long duration (three had generalized vitiligo and one had segmental vitiligo). The samples were taken from the oldest achromic lesions, and the biopsy sites were far from normal skin. In all cases we noted alterations in keratinocytes, Langerhans cells, and melanocytes. We also found lymphocytes in the epidermis, and these cells and macrophages were noted in the dermis. The basal membrane disappeared at some points, and sometimes it was possible to see dermal cells with processes that engulfed either granular material or vesicles of epidermal origin in such areas. Our studies suggest that even in stable vitiligo, achromia implies intense cytologic activity, probably involving cell-mediated cytotoxicity, and ultrastructural findings resemble those of a lichenoid reaction.

Cole disease: hypopigmentation with punctate keratosis of the palms and soles.

Cole disease is an uncommon disorder characterized by distinctive cutaneous hypopigmentation and punctate keratosis of the palms and soles. It is a congenital skin disease with an autosomal dominant inheritance pattern. We report two patients from a family with 15 members, 5 of whom were affected. One of the patients had both types of lesions since birth, while in the other they arose in the first months of life. We studied the pedigree, histopathology, immunohistochemistry, and electron microscopy findings of the hypopigmented macules with the patients' normal skin used as a control. The pedigree showed involvement of both genders, with a Mendelian autosomal dominant inheritance pattern with phenotypic variability in the family. Immunohistochemistry showed a reduction in the melanin pigment in the keratinocytes and normal pigmentation in the melanocytes. Ultrastructural studies showed a strong contrast between the large number of melanosomes in the body and dendrites of the melanocytes, in contrast with the small number of these organelles in the neighboring keratinocytes. These findings suggest that this disease is a primary congenital disorder of the transfer mechanisms of the melanosomes from melanocytes to keratinocytes in hypopigmented lesions, associated with abnormal epidermopoiesis in the punctate hyperkeratosis.

Encefalitis a citomegalovirus en un paciente inmunocompetente: análisis clinico, neuropatologico y ultraestructural / Cytomegalovirus encephalitis in an immunocompetent patient: clinical, neuropathological and ultrastructural analysis

Las encefalitis por citomegalovirus en pacientes inmunocompetentes son excepcionales, siendo un patógeno reconocido en pacientes inmunodeprimidos (SIDA, transplantados). Se reporta el caso clínico de una encefalitis por Citomegalovirus en un adulto joven, sin evidencia de enfermedad inmunosupresora, cuyo diagnóstico fue posible mediante la detección de ADN viral en la biopsia cerebral. Se describen además las singularidades clínicas de este caso y los hallazgos de la anatomía patológica y de la microscopía electrónica comparándolos con los reportados en pacientes inmunodeprimidos

Carcinoma de celulas pequeñas primitivo de esofago / Primary small cell carcinoma of the esophagus

Los carcinomas de células pequeñas (CCP), son neoplasias altamente agresivas, también conocidos como carcinomas de tipo "oat cell" y "non oat cell", carcinoma neuroendócrinos, etc. La mayoría se originan en el pulmón, existe un 5 por ciento que se originan en sitios extrapulmonares. Los originados en esófago son muy raros y representan del 0.05 al 7.6 por ciento de las neoplasias malignas del esófago. Generalmente se presentan en forma diseminada y tienen muy mal pronóstico. Plantean dificultades en el diagnóstico diferencial con otros tumores malignos así como en el tratamiento. Nosotros presentamos 3 casos de CCP primitivos de esófado, discutimos sus características clínicas, histopatológicas y histoquímicas, ultraestructurales, e histogénesis, en relación a la literatura. (AU)

Carcinoma de celulas pequeñas primitivo de esofago / Primary small cell carcinoma of the esophagus

Los carcinomas de células pequeñas (CCP), son neoplasias altamente agresivas, también conocidos como carcinomas de tipo "oat cell" y "non oat cell", carcinoma neuroendócrinos, etc. La mayoría se originan en el pulmón, existe un 5 por ciento que se originan en sitios extrapulmonares. Los originados en esófago son muy raros y representan del 0.05 al 7.6 por ciento de las neoplasias malignas del esófago. Generalmente se presentan en forma diseminada y tienen muy mal pronóstico. Plantean dificultades en el diagnóstico diferencial con otros tumores malignos así como en el tratamiento. Nosotros presentamos 3 casos de CCP primitivos de esófado, discutimos sus características clínicas, histopatológicas y histoquímicas, ultraestructurales, e histogénesis, en relación a la literatura.