Primary Merkel cell carcinoma of the breast in a man with skin graft: a case report / Carcinoma de células de Merkel primario de la mama en un hombre con injerto cutáneo. Reporte de caso

Abstract Introduction: Merkel cell carcinoma (MCC) is a rare and aggressive neuroendocrine skin cancer that usually appears as a flesh-colored or bluish-red nodule on the face, head, or neck. MCC is primarily found in older adults. Case presentation: An 85-year-old white man visited the breast care service of the Servicio de Mastología del Instituto Nacional de Oncología y Radiobiología (National Institute of Oncology and Radiobiology, or INOR by its acronym in Spanish) in Havana, Cuba, due to an increase in volume, color change, and a burning sensation in the right breast. The patient had suffered thermal trauma to the right hemithorax 18 years before the consultation, which was treated with a skin graft of the thigh. Imaging studies (ultrasound, mammography, magnetic resonance imaging, and computed tomography) showed a nodule with imaging features suggestive of malignancy. CCM diagnosis was confirmed by core needle biopsy, reporting positivity of CD-56, CK-7, and Ki-67 markers. Conclusions. Typically, MCC presents as a rapidly growing, firm skin nodule in sun-exposed areas, contrary to the present case, in which the lesion appeared on grafted skin on the right hemithorax. Recognizing imaging findings suggestive of this neoplasm is of great importance for its diagnosis in unusual areas of the body, such as the breast.

Resumen Introducción. El carcinoma de células de Merkel (CCM) es un cáncer neuroendocrino de la piel agresivo y muy poco frecuente que, por lo general, aparece como un nódulo de color carne o rojo azulado en la cara, cabeza o cuello. El CCM ocurre principalmente en adultos mayores. Presentación del caso. Hombre de 85 años, blanco, que asistió al Servicio de Mastología del Instituto Nacional de Oncología y Radiobiología (INOR), en La Habana, Cuba, por aumento de volumen, cambio de color y temperatura en la mama derecha. El paciente había sufrido trauma térmico en el hemitórax derecho 18 años antes de la consulta, el cual fue tratado mediante injerto cutáneo del muslo. En los estudios de imagen (ultrasonido, mamografía, resonancia magnética y tomografía computarizada) se observó un nódulo con características imagenológicas sugestivas de malignidad. El diagnóstico de CCM se confirmó mediante biopsia por punción con aguja gruesa, donde se reportó positividad de marcadores CD-56, CK-7 y Ki-67. Conclusiones. Característicamente, el CCM se presenta como nódulos cutáneos firmes de rápido crecimiento en las áreas expuestas al sol, a diferencia del presente caso, en el que la lesión apareció en la piel injertada en el hemitórax derecho. Reconocer hallazgos imagenológicos sugestivos de esta neoplasia es de gran importancia para el diagnóstico en zonas inusuales del cuerpo como la mama.

Carcinoma de células de Merkel: múltiplas lesões cutâneas primárias no membro inferior / Merkel cell carcinoma: multiple primary skin lesions in the lower limb

Carcinoma de células de Merkel é um tumor neuroendócrino raro e agressivo de pele que usualmente apresenta-se como lesão única na região de cabeça ou pescoço. Relata-se um caso de topografia e apresentação atípicas, com presença de múltiplos e simultâneos tumores na perna esquerda de rápida evolução, associados à linfonodomegalia inguinal palpável, com diagnóstico confirmado por meio de histopatologia e imuno-histoquímica. Realizada exérese de linfonodo inguinal esquerdo e das lesões cutâneas com margem de segurança

Merkel cell carcinoma is a rare and aggressive neuroendocrine skin tumor usually presenting as a single lesion in the head or neck region. We report a case of atypical topography and presentation, with multiple and simultaneous tumors on the left leg of rapid progression associated with palpable inguinal lymphadenopathy and diagnostic confirmation by histopathology and immunohistochemistry. Exeresis of the left inguinal lymph node and skin lesions with a safety margin was performed

BK virus nephropathy in a heart transplant recipient / Nefropatia pelo vírus BK em um receptor de transplante cardíaco

Abstract BK virus nephropathy in kidney transplantation is widely recognized as an important cause of graft dysfunction and loss. In the case of transplants of organs other than kidney, BK virus nephropathy in native kidneys has been recognized as a cause of chronic kidney disease, which is related with immunosuppression; however, the diagnosis is usually late because the renal dysfunction is attributed to other causes, such as toxicity by anticalcineurinic drugs, interstitial nephritis due to medications, hemodynamic changes, diabetes, hypertension, etc. We report a case of BK virus nephropathy in a patient who underwent heart transplantation due to peripartum cardiomyopathy. The kidney biopsy reported active chronic tubulointerstitial nephritis associated with late stage polyomavirus nephritis and the blood viral load for BK virus was positive (logarithm 4.5). The immunosuppressive treatment was reduced, and after two years of follow-up, the patient had stable renal function with a serum creatinine of 2.5 mg/dL (GFR of 23.4 mL/min/1.73m2). We recommend that the BK virus be considered as a cause of renal dysfunction in heart transplant recipients, with the aim of detecting its replication in time to reduce immunosuppressive therapy before irreversible compromise of renal function may manifest.

Resumo A nefropatia pelo vírus BK no transplante renal é amplamente reconhecida como uma importante causa de disfunção e perda do enxerto. No caso de transplantes de órgãos que não sejam rins, a nefropatia pelo vírus BK em rins nativos tem sido reconhecida como uma causa de doença renal crônica, que está relacionada com imunossupressão; entretanto, o diagnóstico é geralmente tardio porque a disfunção renal é atribuída a outras causas, tais como toxicidade por drogas anticalcineurínicas, nefrite intersticial devido a medicamentos, alterações hemodinâmicas, diabetes, hipertensão, etc. Relatamos um caso de nefropatia pelo vírus BK em um paciente que foi submetido a transplante cardíaco devido à cardiomiopatia periparto. A biópsia renal relatou nefrite túbulo-intersticial crônica ativa associada à nefrite por poliomavírus em estágio avançado e a carga viral sanguínea para o vírus BK foi positiva (logaritmo 4,5). O tratamento imunossupressor foi reduzido, e após dois anos de acompanhamento, o paciente apresentava função renal estável com creatinina sérica de 2,5 mg/dL (TFG de 23,4 mL/min/1,73m2). Recomendamos que o vírus BK seja considerado como uma causa de disfunção renal em receptores de transplante cardíaco, com o objetivo de detectar sua replicação a tempo de reduzir a terapia imunossupressora antes que um comprometimento irreversível da função renal possa se manifestar.

Effect of polyoma viremia on 3-year allograft kidney function.

BACKGROUND: Polyoma viremia is associated with damage to renal tubular and urothelial cells. This may imply that a certain level of viremia, even cleared thereafter, could be associated with long-term renal dysfunction. METHODS: We, retrospectively, analyzed 390 first renal transplants adult recipients (≥18 years) who were monitored for BK viremia in the first 12 months and evaluated estimated GFR (MDRD-4 equation) at 1 month and at the last follow-up (959 ± 392 days). RESULTS: One hundred and ninety-nine patients (51%) developed at least one positive viremia: 105 (53%) low viremia (<104  copies/mL), 36 (18%) high viremia (4 × 104  > viremia ≥ 104  copies/mL) and 58 (15%) viremia (≥4 × 104  copies/mL) consistent with polyoma virus associated nephropathy (PyVAN). Out of these 58 patients, 24 (6%) developed bx-proven (SV40+) PyVAN and 34(8.7%) presumptive PyVAN (SV40-). Baseline characteristics, immunosuppression, KDRI, rejection episodes, etc., did not differ among groups but there were more deceased donors and ATG induction therapy in the high viremia group. At last follow-up, all patients in the low, high viremia and presumptive PyVAN (except 2) had cleared BK viremia. Bx-proven PyVAN led to 14 graft losses, 10 due to PyVAN. In the presumptive PyVAN there was only one graft loss registered as due to PyVAN. eGFR, at 1 month after KTx, did not differ among groups (51 ± 22 vs 48 ± 24 vs 45 ± 27 vs 43 ± 18 vs 46 ± 22 mL/min/1.73 m2 ), for no, low and high viremia as well for presumptive PyVAN and bx-proven PyVAN groups, respectively. At the last follow-up, eGFR did not differ between the no, low, and high viremia compared to baseline and to each other but was statistically lower in the presumptive and bx-proven PyVAN (38 ± 15 and 17 ± 7 mL/min/1.73 m2 ) either compared to baseline or to the other groups. CONCLUSIONS: This study shows that low and high levels of BK viremia do not lead to GFR changes although very high viremia levels, compatible with presumptive or bx-proven PyVAN, even if cleared thereafter, lead to allograft damage and decreased GFR.

Tricodisplasia espinulosa asociada a leucemia linfoblástica aguda en edad pediátrica: revisión de la literatura a propósito de un caso / Trichodysplasia spinulosa associated with acute lymphoblastic leukemia in pediatric age: review of the literature regarding a case

La tricodisplasia espinulosa es una patología viral infrecuente causada por un tipo de poliomavirus, el cual se da siempre en contexto de inmunosupresión. Existen reportes que estiman una seroprevalencia en adultos de 70%, y hasta 90% en inmu-nocomprometidos. El cuadro clínico se caracteriza por pápulas color piel hiperqueratósicas en zonas centro faciales, orejas y tronco, asintomáticas o con prurito escaso. Existen métodos de confirmación diagnóstica como PCR o test de Elisa, que no se encuentran disponibles en Chile. Por lo tanto, en nuestro contexto el estudio histopatológico es fun-damental, dada su accesibilidad y que los hallazgos de la biopsia son característicos. El manejo debe siempre considerar, de ser posible, disminuir la in-munosupresión del paciente. Otras medidas son: extracción manual de las lesiones y aplicación de cidofovir o valganciclovir tópicos

Trichodysplasia spinulosa is an infrequent viral pathology caused by a type of polyomavirus, which always occurs in context of immunosuppression. There are reports that estimate sero-prevalence in adults of 70%, and 90% in immunocompromised. Patients have numerous, mildly pruritic, folliculocentric, flesh-colored to pink papules with central keratinaceous spines. There are methods of diagnostic confirmation such as PCR or Elisa test, not available in Chile. The-refore, in our context the histopathological study is fundamental because biopsy findings are cha-racteristic. Management should always consider, if possible, decrease the immunosuppression of the patient. Other measures consist of manual extraction and cidofovir or topical valganciclovir.

Virus polioma en carcinoma de células de Merkel / Polyoma virus in Merkel cell carcinoma

Introducción: El carcinoma de células de Merkel (MCC) es un tumor cutáneo maligno agresivo y de mal pronóstico. La incidencia es mayor en adultos hombres, caucásicos, con edad promedio de 70 años. Feng et al, lograron aislar un nuevo virus en muestras de este tumor, que denominaron virus polioma de células de Merkel (MCPyV). Se ha intentado establecer una relación causal entre el virus y MCC. El virus está integrado al genoma y produciría mutaciones específicas. En muestras de MCC, se ha detectado expresión de oncoproteinas virales (antígenos T) que promueven la replicación viral y tumorogénesis

Introduction: Merkel cell carcinoma (MCC) is an aggressive malignant cutaneous tumor with poor prognosis. Most cases affect elder patient with an average of 70 years of age. Feng et al isolated a new virus, the Merkel cell carcinoma polyoma virus (MCPyV). A causal relationship between MCPyV y MCC has been established. The virus is integrated in the genome and pro-duces specific mutations. MCC samples show ex-pression of viral oncoproteins (T antigens) that promote viral replication and tumorogenesis.

Quantitative detection of BK virus in kidney transplant recipients: a prospective validation study / Detecção quantitativa de vírus BK em receptores de transplante renal: um estudo prospectivo de validação

Abstract Introduction: BK virus (BKV) infection in renal transplant patients may cause kidney allograft dysfunction and graft loss. Accurate determination of BKV viral load is critical to prevent BKV-associated nephropathy (BKVAN) but the cut-off that best predicts BKVAN remains controversial. Objective: To evaluate the performance of a commercial and an in-house qPCR test for quantitative detection of BK virus in kidney transplant recipients. Methods: This was a prospective study with kidney transplant recipients from two large university hospitals in Brazil. Patients were screened for BKV infection every 3 months in the first year post-transplant with a commercial and an in-house real time polymerase chain reaction (qPCR) test. BKVAN was confirmed based on histopathology. The area under the curve for plasma qPCR was determined from receiver operating characteristic analysis. Results: A total of 200 patients were enrolled. Fifty-eight percent were male, 19.5% had diabetes mellitus, and 82% had the kidney transplanted from a deceased donor. BKV viremia was detected in 32.5% and BKVAN was diagnosed in 8 patients (4%). BKVAN was associated with viremia of 4.1 log copies/mL, using a commercial kit. The cut-off for the in-house assay was 6.1 log copies/mL. The linearity between the commercial kit and the in-house assay was R2=0.83. Conclusion: Our study shows that marked variability occurs in BKV viral load when different qPCR methodologies are used. The in-house qPCR assay proved clinically useful, a cheaper option in comparison to commercial qPCR kits. There is an urgent need to make BKV standards available to the international community.

Resumo Introdução: A infecção pelo vírus BK (BKV) em pacientes de transplante renal pode levar a disfunção do aloenxerto renal e perda do enxerto. A determinação precisa da carga viral do BKV é fundamental para prevenir a nefropatia associada ao BKV (BKVAN), mas o ponto de corte de melhor valor preditivo para BKVAN ainda é foco de debates. Objetivo: Avaliar o desempenho de um teste de qPCR comercial e outro desenvolvido internamente para detecção quantitativa de vírus BK em receptores de transplante renal. Métodos: O presente estudo prospectivo incluiu receptores de transplante renal de dois grandes hospitais universitários no Brasil. Os pacientes foram testados para infecção por BKV a cada três meses no primeiro ano pós-transplante com um teste comercial de reação em cadeia de polimerase quantitativa em tempo real (qPCR) e outro desenvolvido internamente. A presença de BKVAN foi confirmada com base na histopatologia. A área sob a curva para o qPCR plasmático foi determinada a partir da análise da característica de operação do receptor. Resultados: Um total de 200 pacientes foram incluídos. Cinquenta e oito por cento eram do sexo masculino, 19,5% tinham diabetes mellitus e 82% tiveram seus rins transplantados de doadores falecidos. Viremia de BKV foi detectada em 32,5% dos pacientes e oito (4%) foram diagnosticados com BKVAN. BKVAN foi associada a viremia de 4,1 log cópias/mL usando o kit comercial. O corte para o ensaio interno foi de 6,1 log cópias/mL. A linearidade entre o kit comercial e o ensaio interno foi R2 = 0,83. Conclusão: Nosso estudo demonstrou uma acentuada variabilidade na carga viral de BKV quando diferentes metodologias de qPCR foram utilizadas. O ensaio interno de qPCR mostrou-se clinicamente útil, além de ser uma opção menos onerosa em relação aos kits comerciais de qPCR. Há uma necessidade urgente de se definir padrões de BKV para a comunidade internacional.

Human polyomavirus infection: Cytological and molecular diagnosis / Infecção pelo poliomavírus humano: diagnóstico citológico e molecular

Summary Few studies directly compare urinary cytology with molecular methods for detecting BK and JC polyomaviruses. Reactivation of BKV infection is the main risk factor for the development of nephropathy in immunocompromised individuals. The limitation of the cytological method can be attributed to the stage where the infected cell does not have specific and sufficient morphological characteristics for a conclusive diagnosis and can be easily interpreted as degenerative alteration. Moreover, morphologically, it is not possible to differentiate the two types of viruses. Polymerase chain reaction (PCR), not only is a sensitive method, but also allows differentiation of viral types without quantification, and therefore is not indicative of nephropathy. According to the American Society of Nephrology, real-time PCR would be the gold standard to indicate nephropathy because it allows quantifying the number of viral copies.

Resumo Poucos estudos comparam diretamente a citologia urinária com métodos moleculares para detecção de poliomavírus BK e JC. A reativação da infecção por BKV é o principal fator de risco para o desenvolvimento de nefropatia em indivíduos imunocomprometidos. A limitação do método citológico pode ser atribuída ao estágio em que a célula infectada não possui características morfológicas específicas e suficientes para um diagnóstico conclusivo, podendo ser facilmente interpretada como alteração degenerativa. Além do mais, morfologicamente, não é possível diferenciar os dois tipos virais. A reação em cadeia pela polimerase (PCR), além de ser um método sensível, permite diferenciar os tipos virais sem quantificá-los, não sendo, portanto, indicativa de nefropatia. Segundo a American Society of Nephrology, a PCR em tempo real seria o padrão-ouro para indicar nefropatia, pois permite quantificar o número de cópias virais.

Distribution and genetic diversity of the human polyomaviruses JC and BK in surface water and sewage treatment plant during 2009 in Porto Alegre, Southern Brazil / Distribuição e diversidade genética dos poliomavírus humanos JC e BK em águas superficiais e de estação de tratamento de esgoto durante 2009 em Porto Alegre, sul do Brasil

Abstract The human polyomaviruses JC and BK (JCPyV and BKPyV) are ubiquitous, species-specific viruses that belong to the family Polyomaviridae. These viruses are known to be excreted in human urine, and they are potential indicators of human wastewater contamination. In order to assess the distribution of both JCPyV and BKPyV in urban water samples collected from a sewage treatment plant (STP) and from a canalized water stream of Porto Alegre, Brazil, two nested-PCR assays were optimized and applied to the samples collected. The amplicons obtained were submitted to sequencing, and the sequences were analyzed with sequences of human polyomaviruses previously deposited in GenBank. Twelve out of 30 water samples (40%) were JCPyV positive, whereas six samples (20%) were BKPyV positive. The sequencing results confirmed the presence of JCPyV subtypes 1 and 3, whereas only BKPyV Ia and Ib were found. This study shows for the first time the presence of human polyomaviruses in surface water and in samples collected in a sewage treatment plant in southern Brazil.

Resumo Os poliomavírus humanos JC e BK (JCPyV e BKPyV) são virus ubíquos, espécie-específicos, pertencentes à família Polyomaviridae. Estes vírus são conhecidos por serem excretados pela urina humana, sendo considerados potenciais indicadores de contaminação por águas residuais urbanas. Buscando acessar a distribuição de JCPyV e BKPyV em amostras de águas coletadas de uma estação de tratamento de esgoto e de um arroio canalizado de Porto Alegre, Brasil, duas técnicas de nested-PCR foram otimizadas e aplicadas às amostras coletadas. Os amplificados obtidos foram submetidos ao sequenciamento e suas sequências analisadas com base em sequências de poliomavírus humanos previamente depositadas no GenBank. Doze de 30 amostras de água (40%) foram positivas para JCPyV, enquanto 6 amostras (20%) foram positivas para BKPyV. Os resultados do sequenciamento confirmaram a presença dos subtipos 1 e 3 de JCPyV, enquanto apenas os BKPyV Ia e Ib foram encontrados. Este estudo demonstra pela primeira vez a presença de poliomavírus humanos em águas superficiais e em amostras coletadas em uma estação de tratamento de esgoto na região sul do Brasil.

Distribution and genetic diversity of the human polyomaviruses JC and BK in surface water and sewage treatment plant during 2009 in Porto Alegre, Southern Brazil

Abstract The human polyomaviruses JC and BK (JCPyV and BKPyV) are ubiquitous, species-specific viruses that belong to the family Polyomaviridae. These viruses are known to be excreted in human urine, and they are potential indicators of human wastewater contamination. In order to assess the distribution of both JCPyV and BKPyV in urban water samples collected from a sewage treatment plant (STP) and from a canalized water stream of Porto Alegre, Brazil, two nested-PCR assays were optimized and applied to the samples collected. The amplicons obtained were submitted to sequencing, and the sequences were analyzed with sequences of human polyomaviruses previously deposited in GenBank. Twelve out of 30 water samples (40%) were JCPyV positive, whereas six samples (20%) were BKPyV positive. The sequencing results confirmed the presence of JCPyV subtypes 1 and 3, whereas only BKPyV Ia and Ib were found. This study shows for the first time the presence of human polyomaviruses in surface water and in samples collected in a sewage treatment plant in southern Brazil.

Resumo Os poliomavírus humanos JC e BK (JCPyV e BKPyV) são virus ubíquos, espécie-específicos, pertencentes à família Polyomaviridae. Estes vírus são conhecidos por serem excretados pela urina humana, sendo considerados potenciais indicadores de contaminação por águas residuais urbanas. Buscando acessar a distribuição de JCPyV e BKPyV em amostras de águas coletadas de uma estação de tratamento de esgoto e de um arroio canalizado de Porto Alegre, Brasil, duas técnicas de nested-PCR foram otimizadas e aplicadas às amostras coletadas. Os amplificados obtidos foram submetidos ao sequenciamento e suas sequências analisadas com base em sequências de poliomavírus humanos previamente depositadas no GenBank. Doze de 30 amostras de água (40%) foram positivas para JCPyV, enquanto 6 amostras (20%) foram positivas para BKPyV. Os resultados do sequenciamento confirmaram a presença dos subtipos 1 e 3 de JCPyV, enquanto apenas os BKPyV Ia e Ib foram encontrados. Este estudo demonstra pela primeira vez a presença de poliomavírus humanos em águas superficiais e em amostras coletadas em uma estação de tratamento de esgoto na região sul do Brasil.

Poliomavirus en sistema nervioso central, una aproximación imagenológica / Polyomaviruses and central nervous system disease

The polyomavirus are a family of opportunistic virus, which belongs to the JC virus whose primary manifestation is the Progressive Multifocal Leukoencephalopathy and neuronopathy of granulosa cells. Recently given the use of PCR for BK virus in transplant patients have also been described CNS pathologies in relation to this, and most frequent encephalitis and leukoencephalopathy. Each entity has a compatible clinical and genetic testing have allowed a diagnosis of high specificity, however the RNM is the great diagnostic pillar in these pathologies, allowing differentiate the different entities, the progression of lesions and response to treatment, especially in cases where it is indicated antiretroviral therapy, as gadolinium enhancement and mass effect may suggest Syndrome Immune and worse prognosis.

Los Poliomavirus son una familia de virus oportunistas, al cual pertenece el virus JC cuya principal manifestación es la Leucoencefalopatía Multifocal Progresiva y la Neuronopatía de Células Granulosas. Recientemente, dada la utilización de PCR para virus BK en LCR en pacientes trasplantados, también se han descrito patologías de SNC en relación a éste, siendo lo más frecuente la Encefalitis y la Leucoencefalopatía. Cada entidad tiene un contexto clínico compatible y las pruebas genéticas han permitido un diagnóstico de alta especificidad, sin embargo, la RNM es el gran pilar diagnóstico en estas patologías, permitiendo diferenciar las distintas entidades, la progresión de las lesiones y la respuesta a tratamiento, especialmente en los casos en que está indicado la terapia antirretroviral, pues la captación de gadolinio y el efecto de masa pueden sugerir un Síndrome de Reconstitución Inmune y peor pronóstico.

Nefropatía por poliomavirus en un paciente inmunosuprimido por trasplante renal secundario a la enfermedad de arteritis de Takayasu / Poliomavirus nephropathy in an immunosuppressed patient with a renal transplant secondary to Takayasu arteritis

La nefropatía por poliomavirus es una enfermedad que predomina en los pacientes con trasplante renal por el tratamiento inmunosupresor para manutención del injerto renal. La prevalencia actual de esta enfermedad oscila entre el 1 y el 14%. La sospecha de la enfermedad se da por la presencia de decoy cells en el examen de orina y el diagnóstico, mediante el hallazgo de inclusiones virales en la biopsia renal. Se describe el caso de un paciente con trasplante renal secundario a arteritis de Takayasu, que presenta disfunción renal evidenciada por elevación progresiva de creatinina sérica, por lo que se le realiza una biopsia renal en donde se observaron inclusiones nucleares virales que permitieron concluir el diagnóstico.

Polyomavirus nephropathy is a disease that predominates in renal transplant patients due to the immunosuppressive treatment for the maintenance of the renal graft. The current prevalence of this disease ranges between 1-14%. The suspicion of the disease comes from the presence of decoy cells in urine samples and the gold standard for the diagnosis is the presence of viral inclusions in the renal biopsy. In this case report, we describe a patient with a renal transplant secondary to Takayasu arteritis who presented renal failure evidenced by progressive elevation of serum creatinine. The renal biopsy showed viral inclusions, confirming the diagnosis.

Nefropatía asociada a poliomavirus BK en trasplante renal / BK polyomavirus-associated nephropathy in kidney transplant

El objetivo del presente reporte es dar a conocer los dos primeros casos de nefropatía del injerto asociada a poliomavirus BK (NPBK) ocurridos en el Hospital Edgardo Rebagliati Martins, EsSalud, Lima, Perú. El diagnóstico definitivo de la NPBK se corroboró mediante biopsia renal y estudio de microscopia electrónica. En el caso 1, el deterioro funcional renal no se controló a pesar de reducir la inmunosupresión y añadir drogas antivirales (leflunamide y ciprofloxacina), evolucionando a falla renal y su posterior acceso a retrasplante renal. En el caso 2, la alternativa terapéutica se basó en infusión de inmunoglobulina endovenosa asociada a reducción de la inmunosupresión, resultando en moderada mejora histológica y estabilización de la función renal. En ambos injertos renales hubo concomitantemente NPBK y lesiones histológicas compatibles con rechazo agudo celular pendientes de interpretar. En conclusión, la presencia del poliomavirus BK representa serio problema en el riñón trasplantado. La mejor conducta terapéutica se basa en el diagnóstico precoz y subsecuente reducción de la inmunosupresión. Es imprescindible disponer de metodología apropiada que posibilite un diagnóstico preciso. Se utiliza tamizaje de células señuelo o marcadoras (decoy cells) en orina, reacción de cadena polimerasa (PCR), biopsia renal o la microscopia electrónica como método valioso de ayuda en el diagnóstico etiológico viral. Se considera el retrasplante como opción ante la pérdida del injerto por NPBK (caso 1)...

Two documented cases of BK polyomavirus-associated nephropathy (BKVN) seen at Hospital Edgardo Rebagliati Martins, EsSalud, Lima, Peru are reported. Final BKVN diagnosis was confirmed by renal biopsy and electron microscopy study. Case 1: Renal functional deterioration was not controlled despite reduction of immunosuppression and addition of antiviral drugs (leflunomide and ciprofloxacin), evolving to renal failure and subsequent kidney retransplantation. Case 2: The therapeutical management consisted in intravenous immunoglobulin infusion linked to reduction of immunosuppression; this resulted in modest histological improvement and stabilization of renal function. Both renal grafts concomitantly presented BKVN and histological lesions consistent with acute rejection, pending interpretation. In conclusion presence of BK polyomavirus is a serious problem for transplanted kidneys. The best treatment is based on early diagnosis and subsequent reduction of immunosuppression. It is essential to have an appropriate methodology for precise diagnosis. Early electron microscopy is a valuable method for viral etiologic diagnosis. Retransplantation is considered a treatment option when faced with possible BKVN-related graft loss (Case 1)...

Virus como inductores de neoplasias cutáneas / Viruses as agents inducing cutaneous neoplasms

El rol oncogénico de los virus en las neoplasias cutáneas es conocido por el hombre desde hace más de un siglo, cuando se atribuía el origen de la verruga vulgar al virus papiloma humano (VPH). En la actualidad, las neoplasias inducidas por virus pueden agruparse en tumores sólidos y procesos linfoproliferativos. Destacan entre los primeros el VPH, del cual ahora conocemos numerosos serotipos, cada uno vinculado a una neoplasia específica, el herpesvirus humano tipo 8 que produce el sarcoma de Kaposi y el poliomavirus vinculado al carcinoma de Merkel. Entre los procesos linfoproliferativos debemos mencionar al virus linfotrópico de células T humanas tipo 1 (HTLV-1) responsable de los linfomas de células T, en los cuales el compromiso cutáneo es inespecífico, con un amplio espectro de presentaciones clínicas y, que por consiguiente, plantean un reto para el diagnóstico diferencial. En este grupo también se encuentra el virus Epstein Barr vinculado a los linfomas nasales de Células NK/T y a los linfomas tipo Hidroa, de reciente descripción. En esta era en la que lo genético y lo molecular priman en las investigaciones en cáncer, no podemos dejar de lado el concepto de neoplasia como resultado de la infección por un agente viral, lo que abre una nueva veta de posibilidades de tratamiento anticanceroso basado en medicamentos antivirales.

The oncogenic role of viruses in cutaneous neoplasms has been known by humankind for more than a century, when the origin of the common wart, or verruca vulgaris, was attributed to the human papilloma virus (HPV). Currently, virus-induced cutaneous neoplasms may be grouped into solid tumors and lymphoproliferative disorders. HPV, from which various serotypes are now known, each being linked to a specific neoplasm, the human herpes virus type 8 producing Kaposi sarcoma, and the Merkel cell polyomavirus, highlight among the first group. Regarding the lymphoproliferative disorders, we should mention the human T-lymphotropic virus type I (HTLV-1), which is responsible for the T-cell lymphomas, in which the cutaneous manifestations are non-specific and have a wide spectrum, thus posing a challenge for differential diagnosis. The Epstein Barr virus, linked to nasal lymphomas of NK/T-cells and Hydroa-like cutaneous lymphomas, is also part of this group. In an era in which the genetic and molecular aspects of cancer research prevail, we may not leave behind the concept of neoplasms as a result an infection with a viral agent, which opens a wide array of new possibilities for cancer treatment based on antiviral drugs.