Near-fatal cocaine intoxication in an infant with thrombotic microangiopathy associated with multiple organ failure / Intoxicação grave por cocaína em criança com microangiopatia trombótica associada à falência múltipla de órgãos

ABSTRACT Objective: To report a pediatric case of drug-induced thrombotic microangiopathy caused by cocaine Case description: We report a nine-month-old patient who developed thrombotic microangiopathies after extreme cocaine intoxication, multiple organ dysfunction syndrome with hemodynamic dysfunction, anuric renal failure, liver failure, encephalopathy, and myocardial injury, corresponding phenotypically to thrombocytopenia-associated multiple organ failure. The patient received continuous venous hemofiltration and therapeutic plasma exchange, recovering satisfactorily. She was discharged after 30 days of hospitalization under the guidance of the childcare service, and was healthy after one year of follow-up. Toxicological samples confirmed high levels of cocaine and derivatives in blood, urine and hair. Comments: To our knowledge, this is the first reported pediatric case. There are particularities of cocaine intoxication pathophysiology that can trigger thrombotic microangiopathies because of vasoconstriction, direct endothelial injury, platelet activation, and increasing von Willebrand factor and fibrinogen levels. All of which results in a prothrombotic state, inflammatory dysregulation, and microvascular thrombi. The increasing use of cocaine, especially among young adults, puts children at high risk of toxicity, either by passive unintentional exposure, or abuse due to the increased availability in homes.

RESUMO Objetivo: Relatar um caso pediátrico de microangiopatia trombótica induzida por drogas causada por cocaína Descrição do caso: Relatamos uma paciente de nove meses de idade que desenvolveu microangiopatia trombótica após intoxicação extrema por cocaína, síndrome de disfunção de múltiplos órgãos com disfunção hemodinâmica, insuficiência renal anúrica, insuficiência hepática, encefalopatia e lesão miocárdica, correspondendo fenotipicamente à falência múltipla de órgãos associada à trombocitopenia. A paciente recebeu hemofiltração venosa contínua e plasmaférese terapêutica, recuperando-se satisfatoriamente. Recebeu alta após 30 dias de internação sob orientação do serviço de puericultura e estava saudável após um ano de seguimento. Amostras toxicológicas confirmaram altos níveis de cocaína e derivados no sangue, urina e cabelos. Comentários: Até onde sabemos, este é o primeiro caso pediátrico relatado. Existem particularidades da fisiopatologia da intoxicação por cocaína que podem desencadear a microangiopatia trombótica devido à vasoconstrição, lesão endotelial direta, ativação plaquetária e aumento do fator de von Willebrand e dos níveis de fibrinogênio. Tudo isso resulta em um estado pró-trombótico, desregulação inflamatória e trombos microvasculares. O uso crescente de cocaína, principalmente entre adultos jovens, coloca as crianças em alto risco de toxicidade, seja por exposição passiva não intencional ou abuso devido à maior disponibilidade nas residências.

Chronic gemcitabine-induced thrombotic microangiopathy in the kidneys / Microangiopatía trombótica crónica localizada en riñones asociada al uso de gemcitabina

Abstract Thrombotic microangiopathies (TMAs) are characterized by microvascular occlusion secondary to diffuse endothelial damage which produces inflammation, platelet aggregation and red blood cell destruction, causing ischemic injury to the affected organ. They are clinically characterized by Coombs-negative microangiopathic hemolytic anemia, and multiple organ damage (mainly of the kidneys, central nervous system, cardiovascular apparatus and gastrointestinal tract). They may occur systemically or locally, and they have multiple etiologies. In patients with cancer, determining the cause of thrombotic microangiopathy is a great diagnostic challenge, with the most frequent etiologies being active malignant neoplasms, disseminated intravascular coagulation, infections and antineoplastic drugs. We present the clinical case of a patient with unresectable pancreatic adenocarcinoma on chronic gemcitabine treatment, and highlight the importance of suspecting and distinguishing chemotherapy-induced TMAs from neoplasm-induced TMAs, as their prognosis and treatment are very different. (Acta Med Colomb 2022; 47. DOI:https://doi.org/10.36104/amc.2022.2249).

Resumen Las microangiopatías trombóticas (MAT) se caracterizan por la oclusión microvascular como consecuencia de una lesión endotelial difusa que produce inflamación, agregación plaquetaria y destrucción de glóbulos rojos, causando daño isquémico del órgano afectado. Se caracterizan clínicamente por anemia hemolítica microangiopática, Coombs negativo, daño multiorgánico (principalmente de riñones, sistema nervioso central, aparato cardiovascular y tracto gastrointestinal). Su presentación puede ser sistémica o localizada y sus etiologías son múltiples. En los pacientes con cáncer es un gran reto diagnóstico establecer la causa de la microangiopatía trombótica, siendo las etiologías más frecuentes la neoplasia maligna activa, la coagulación intravascular diseminada, infecciones y medicamentos antineoplásicos. Se presenta el caso clínico de una paciente con adenocarcinoma cáncer de páncreas irresecable, en manejo crónico con gemcitabina y se resalta la importancia de sospechar y distinguir la MAT inducida por quimioterapia, de la causada por la neoplasia ya que el pronóstico y tratamiento son muy diferentes. (Acta Med Colomb 2022; 47. DOI:https://doi.org/10.36104/amc.2022.2249).

Brote de 4 casos leptospirosis de un grupo familiar en zona rural tropical de Colombia: un reporte de caso / Outbreak of 4 leptospirosis cases in a family group in tropical rural zone of Colombia: a case report

La leptospirosis es una zoonosis con manifestaciones clínicas causadas por espiroquetas patógenas del género Leptospira spp. Su curso puede ser desde enfermedad leve hasta un síndrome ictero-hemorrágico severo denominado enfermedad de Weil. Se estudió un brote epidemiológico constituido por una serie de cuatro casos de leptospirosis de severidad moderada a severa, ocurridos en una zona rural de clima tropical en los llanos orientales de Colombia, a 450 metros sobre el nivel del mar en una familia visitante en Puerto Lleras, Meta, Colombia. Probablemente secundario al consumo de aguas contaminadas por orina de roedores. Las pacientes fueron ingresadas bajo la sospecha de un síndrome ictérico de origen infeccioso con un falso positivo para antígeno de superficie de hepatitis B. Dos pacientes desarrollaron síndrome de Weil asociado a microangiopatía trombótica por lo que requirieron manejo en unidad de cuidados intensivos (UCI) sin embargo, una de ellas fallece y las otras dos pacientes desarrollan signos y síntomas moderados evidenciando un curso variable de la enfermedad. En nuestro país existe una sobre notificación de síndromes febriles, ictéricos e icterohemorragicos de diferentes etiologías y difícil diagnóstico por lo que la leptospirosis tiende a ser confundida o ignorada como diferencial en muchos casos.

Leptospirosis is a zoonosis with clinical manifestations caused by pathogenic spirochetes of the genus Leptospira spp. Its course can range from mild illness to a severe jaundice-hemorrhagic syndrome called Weil's disease. An epidemiological outbreak consisting of a series of four cases of leptospirosis of moderate to severe severity, which occurred in a rural area with a tropical climate in the eastern plains of Colombia, at 450 meters above sea level, was studied in a visiting family in Puerto Lleras, Meta, Colombia. Probably secondary to the consumption of water contaminated by rodent urine. The patients were admitted on suspicion of an infectious jaundice syndrome with a false positive for hepatitis B surface antigen. Two patients developed Weil's syndrome associated with thrombotic microangiopathy, requiring ICU management, however, one of them died and the other two patients develop moderate signs and symptoms showing a variable course of the disease. In our country there is an overreporting of febrile, jaundice and jaundice syndromes of different etiologies and difficult diagnosis, so that leptospirosis tends to be confused or ignored as differential in many cases.

Púrpura trombocitopénica trombótica en un paciente con infección por VIH / Thrombotic thrombocytopenic purpura, in a HIV-infected patient: case report

Resumen Las manifestaciones hematológicas de la infección por el VIH son frecuentes y variadas debido a su capacidad de afectar prácticamente todas las líneas celulares. Dentro de éstas, la púrpura trombocitopénica trombótica (PTT) es una de las entidades que constituyen las microangiopatías trombóticas. Se caracteriza por la presencia de trombocitopenia y anemia hemolítica microangiopática con alteración de la función renal. Actualmente, la co-existencia de estas dos entidades es poco frecuente debido a la terapia anti-retroviral de alta efectividad (TARV) Presentamos el caso de un paciente de 28 años, quien consultó por fiebre asociada a episodios de gingivorragia, palidez mucocutánea generalizada y debilidad progresiva. Los estudios evidenciaron una anemia y trombocitopenia grave. Se encontraron esquistocitos y microesferocitos en el frotis de sangre periférica con actividad de la enzima ADAMTS 13 disminuida (6,8%). Se confirmó el diagnóstico de una PTT como manifestación inicial de una infección por VIH. Se indicó manejo con plasmaféresis e inicio de TARV con buena respuesta.

Abstract Hematological manifestations for human immunodeficiency virus (HIV) infection are frequent and diverse due to its ability to affect almost all cell lines. Among these, thrombotic thrombocytopenic purpura (TTP) is one of the thrombotic microangiopathies syndromes, characterized by the presence of thrombocytopenia and microangiopathic hemolytic anemia with impaired renal function. Nowadays, the relationship between these two entities is rare given the current highly active antiretroviral therapy (HAART). We report the case of a 28-year-old patient, who presented with fever associated with gingival bleeding, generalized mucocutaneous pallor and progressive weakness. Routine investigations showed anemia and severe thrombocytopenia, schistocytes and micro spherocytes in peripheral blood smear. Required blood transfusion, with decreased ADAMTS 13 enzyme activity (6.8%). With these findings,TTP was diagnosed as the initial manifestation of the HIV infection. The patient received management with five sessions of plasmapheresis and HAART with subsequent improvement.

Update on thrombocytopenia in pregnancy / Atualização sobre trombocitopenia na gravidez

Abstract Thrombocytopenia, defined as platelet count < 150,000mm3, is frequently diagnosed by obstetricians since this parameter is included in routine surveillance during pregnancy, with an incidence of between 7 and 12%. Therefore, decisions regarding subsequent examination and management are primordial. While most of the cases are due to physiological changes, as gestational thrombocytopenia, other causes can be related to severe conditions that can lead to fetal or maternal death. Differentiating these conditions might be challenging: they can be pregnancy-specific (pre-eclampsia/ HELLP syndrome [hemolysis, elevated liver enzymes, low platelets]), or not (immune thrombocytopenia purpura, thrombotic thrombocytopenic purpura or hemolytic uremic syndrome). Understanding the mechanisms and recognition of symptoms and signs is essential to decide an adequate line of investigation. The severity of thrombocytopenia, its etiology and gestational age dictates different treatment regimens.

Resumo Trombocitopenia, definida como uma contagem de plaquetária < 150.000mm3, é frequentemente diagnosticada pelos obstetras, uma vez que este parâmetro está incluído na vigilância de rotina durante a gravidez, com uma incidência de entre 7 e 12%. Assim, decisões relativas à avaliação e orientação subsequentes são primordiais. Embora a maioria dos casos ocorra devido a alterações fisiológicas, como a trombocitopenia gestacional, outras causas podem estar relacionadas com condições graves que podem levar à morte fetal ou materna. Distinguir entre estas entidades pode ser desafiante: elas podem ser específicas da gravidez (pré-eclâmpsia/síndrome HELLP [hemolysis, elevated liver enzymes, low platelets]) ou não (púrpura trombocitopênica imune, púrpura trombocitopênica trombótica ou síndrome hemolítico urêmico). Compreender os mecanismos e reconhecer os sinais e sintomas é essencial para decidir uma adequada linha de investigação. A severidade da trombocitopenia, a sua etiologia e a idade gestacional ditam regimes de tratamento diferentes.

Microangiopatía trombótica sistémica asociada a mutaciones del complemento en trasplante renal donante vivo. reporte de caso / Systemic thrombotic microangiopathy associated with complement pathway mutations in living donor kidney transplant. case report

RESUMEN El síndrome urémico hemolítico (SUH) se caracteriza por la presencia de anemia hemolítica, plaquetopenia e insuficiencia renal aguda. Si bien se distingue clásicamente en típico o infeccioso y atípico, es menester reconocer situaciones clínicas en las que se pone de manifiesto, como por ejemplo, embarazo, puerperio inmediato, tumores, trasplante, drogas, etc., condiciones clínicas que han sido denominadas amplificadoras del complemento. La recurrencia postrasplante delsíndrome urémico hemolítico atípico (SUHa) ha sido descrita en porcentajes variables en pacientes con mutaciones del factor H, factor B, factor I y C3, y gen de la trombomodulina, en reportes de casos aislados. Se presenta el caso de una paciente con enfermedad renal crónica (ERC) secundaria a agenesia renal, receptora preemptive de un riñón de donante vivo relacionado que presentó disfunción del injerto renal secundaria a microangiopatía trombótica, asociado a complicación neurológica, hemorragias, disfunción orgánica múltiple y óbito. Se describen los hallazgos del estudio genético y anatomopatológico de necropsia.

ABSTRACT Hemolytic uremic syndrome (HUS) is characterized by the presence of hemolytic anemia, thrombocytopenia and acute kidney injury. Although it is usually distinguished as typical or infectious and atypical, it is necessary to recognize clinical situations in which it is revealed, such as pregnancy, immediate postpartum period, tumors, transplantation, drugs, etc., i.e. clinical conditions that have been called complement-amplifying conditions. Post-transplantation recurrence of atypical hemolytic uremic syndrome (aHUS) has been described in variable percentages in patients with mutations of factor H, factor B, factor I and C3, and thrombomodulin gene, in reports of isolated cases. We present the case of a patient with chronic kidney disease (CKD) secondary to renal agenesis, a preemptive recipient of a related living donor kidney, which presented renal graft dysfunction secondary to thrombotic microangiopathy, associated with neurological complications, hemorrhages, multiple organ dysfunction and death. The findings of the genetic and pathological autopsy study are described.

Endothelial lesion and complement activation in patients with Scleroderma Renal Crisis / Lesão endotelial e ativação do complemento em pacientes com crise renal esclerodérmica

Abstract In kidney biopsies reviews, scleroderma renal crisis (SRC) is characterized by vascular endothelial injuries, C4d deposits on peritubular vessels, and acute and chronic injuries coexisting on the same biopsy. The clinical signs of thrombotic microangiopathy (TMA) are described in systemic sclerosis (SSc), nevertheless, it has not been related to acute injuries described on kidney biopsies. We report a case of SRC in a patient with scleroderma-dermatomyositis overlap syndrome, which also showed clinical and histopathological data of TMA. On fundus examination, a severe acute hypertensive retinopathy was found. The kidney biopsy showed severe endothelial damage with widening of mucoid cells at the level of the intima, focal concentric proliferation on most small arterioles, and C3, C4d, and IgM deposits along the capillary walls. The genetic study of complement only showed the presence of membrane cofactor protein (MCP) risk haplotypes, without other genetic complement disorders. We understand that in a patient with TMA and SSc, the kidney damage would be fundamentally endothelial and of an acute type; moreover, we would observe clear evidence of complement activation. Once further studies correlate clinical-analytical data with anatomopathological studies, it is likely that we will be forced to redefine the SRC concept, focusing on the relationship between acute endothelial damage and complement activation.

Resumo Nas revisões de biópsias renais, a crise renal esclerodérmica (CRE) é caracterizada por lesões endoteliais vasculares, depósitos de C4d em vasos peritubulares e lesões agudas e crônicas que coexistem na mesma biópsia. Os sinais clínicos de microangiopatia trombótica (MAT) são descritos na esclerose sistêmica (ES); no entanto, não foram relacionados às lesões agudas descritas nas biópsias renais. Relatamos um caso de CRE em um paciente com síndrome de superposição de esclerodermia-dermatomiosite, que também apresentou dados clínicos e histopatológicos de MAT. No exame de fundo do olho, foi encontrada uma retinopatia hipertensiva aguda grave. A biópsia renal mostrou lesão endotelial grave com alargamento das células mucoides ao nível da íntima, proliferação concêntrica focal na maioria das pequenas arteríolas e depósitos de C3, C4d e IgM ao longo das paredes dos capilares. O estudo genético do complemento mostrou apenas a presença de haplótipos de risco da proteína cofator de membrana (PCM), sem outros distúrbios genéticos do complemento. Entendemos que em um paciente com MAT e ES, o dano renal seria fundamentalmente endotelial e do tipo agudo; além disso, observaríamos evidências claras de ativação do complemento. Uma vez que novos estudos correlacionam dados clínico-analíticos com estudos anatomopatológicos, é provável que sejamos forçados a redefinir o conceito de CRE, enfocando a relação entre dano endotelial agudo e ativação do complemento.

Paraquat-induced Thrombotic Microangiopathy: The Pathophysiology in Hyperacute Paraquat Poisoning Deaths / Microangiopatía trombótica inducida por paraquat: fisiopatología de las muertes por envenenamiento hiperagudo con paraquat

ABSTRACT This paper described the pathophysiology of suicide deaths from paraquat poisoning which occurred in patients who died in fewer than 24 hours after ingesting paraquat. These deaths were referred to as hyperacute paraquat poisoning deaths. Thrombotic microangiopathy was the predominant pathological finding in all these cases and was evident in the brain, lung, heart, kidneys and in all organs and tissues examined. Of note, diffuse alveolar capillary thrombosis occurred, causing damage to alveolar walls, including those in subpleural locations, resulting in focal visceral pleural rupture leading to pneumothorax and pneumomediastinum in these cases, thus giving rise to yet another mechanism of pneumothorax and pneumomediastinum in paraquat toxicity. Thrombotic microangiopathy is the major pathological mechanism that underlies paraquat poisoning and has not hitherto been reported.

RESUMEN El presente trabajo describe la fisiopatología de las muertes por suicidio por intoxicación con paraquat en pacientes que murieron en menos de 24 horas después de ingerirlo. Estas muertes fueron referidas como muertes por envenenamiento hiperagudo con paraquat. La microangiopatía trombótica fue el hallazgo patológico predominante en todos estos casos, y se hizo evidente en el cerebro, el pulmón, el corazón, los riñones y en todos los órganos y los tejidos examinados. Es de notar que se produjo una trombosis capilar alveolar difusa, que causó daño a las paredes alveolares, incluyendo aquellas en localizaciones subpleurales. Esto trajo como resultado la ruptura pleural visceral focal que condujo al neumotórax y al neumomediastino en estos casos, dando así lugar a otro mecanismo de neumotórax y neumomediastino en la toxicidad del paraquat. La microangiopatía trombótica es el mecanismo patológico principal que subyace en el envenenamiento por paraquat, y no ha sido reportada hasta el momento.

Actualización diagnóstico-terapéutica del síndrome antifosfolípido o de Hughes / Therapeutic diagnostic update of Hughes antiphospholipid syndrome

El síndrome antifosfolipídico es una enfermedad del sistema inmune (trombofilia), que se caracteriza por la asociación de los anticuerpos antifosfolipídicos con trombosis de repetición, abortos o pérdidas fetales recurrentes y trombocitopenia. Descrito inicialmente en el lupus eritematoso sistémico, aparece también en personas que no reúnen criterios de alguna enfermedad conocida, por lo que su identificación y tratamiento adquieren gran importancia en personas con fenómenos trombóticos aparentemente inexplicables y en mujeres con abortos y muertes fetales recurrentes sin otra causa reconocible. A pesar de que los fenómenos clínicos que caracterizan a esta enfermedad ocurren frecuentemente, la incidencia es baja. Por lo que toma importancia, la identificación de los anticuerpos antifosfolípidos mediante ensayos para su detección. El síndrome antifosfolípido no tiene cura, pero pueden prevenirse los eventos trombóticos corrigiendo los factores de riesgo para trombosis y usando una terapia con anticoagulante oral para el resto de la vida.

Antiphospholipid Syndrome is a disease of the immune system (thrombophilia), which is characterized by the association of antiphospholipid antibodies with recurrent thrombosis, abortions or recurrent fetal losses and thrombocytopenia. Initially described in systemic lupus erythematosus, it also appears in people who do not meet the criteria of a known disease, so its identification and treatment acquire great importance in people with apparently inexplicable thrombotic phenomena and in women with abortions and recurrent fetal deaths without other cause recognizable. Although the clinical phenomena that characterize this disease occur frequently, the incidence is low. So it is important, the identification of antiphospholipid antibodies through tests for their detection. Antiphospholipid Syndrome has no cure, but thrombotic events can be prevented by correcting the risk factors for thrombosis and using an oral anticoagulant therapy for the rest of your life.

Microangiopatía trombótica en Lupus Eritematoso Sistémico: a propósito de tres casos / Thrombotic microangiopathy in Systemic Lupus Erythematosus: three cases report

RESUMEN Se describen tres casos de pacientes con lupus y microangiopatía. Los casos descritos representan las principales condiciones asociadas a lupus que pueden generar anemia microangiopática, como son: anemia hemolítica microangiopática, síndrome antifosfolípido con microangiopatía localizada y síndrome antifosfolípido catastrófico. La alta mortalidad que conlleva la anemia microangiopática, sin el tratamiento oportuno, hace necesario motivar a los clínicos a conocer ampliamente la enfermedad para poder reconocerla prontamente.

SUMMARY In this article, we describe three cases of lupic patients that developed microangiopathy. Those cases represent the principal etilogies of microangiopathy in Lupus such as, microangiopathic haemolytic anaemia and antiphospholipid syndrome with and without castastrofic manifestations. The clinicians must know deeply about this condition to recognize it in a timely manner.

Microangiopatía trombótica y lupus erimatoso sistémico / Thrombotic microangiopathy and systemic lupus erythematosus

Paciente de 28 años, Testigo de Jehová, con diagnóstico de lupus eritematoso sistémico con compromiso renal cuatro años antes (nefritis lúpica clase IV con remisión completa). A los 2 años y medio reactiva el compromiso renal y agrega durante la fase de reinducción compromiso hematológico con anemia y plaquetopenia severa, esquistocitos en frotis de sangre periférico, haptoglobina y complemento disminuido. Se plantea el diagnóstico de microangiopatía trombótica (MAT) de causa primaria versus secundaria. Por cuestiones religiosas se trata la MAT con Rituximab, sumándose posteriormente Eculizumab. No se realizó anatomía patológica renal, ni se realizó plasmaféresis por dicho motivo. Requirió tratamiento dialítico. El ADAMTS XIII era normal y presentaba importante consumo de C3. A los 6 meses de seguimiento, sin actividad lúpica, plaquetopenia ni anemia hemolítica se discontinuó Rituximab y Eculizumab. Continuó en tratamiento dialítico crónico

A 28-year-old patient, a Jehovah's Witness, diagnosed with systemic lupus erythematosus with renal involvement four years earlier (class IV lupus nephritis with complete remission). After 2 and a half years, she reactivates renal involvement and adds during the re-induction phase hematological commitment with anemia and severe thrombocytopenia, schistocytes in peripheral blood smears, haptoglobin and decreased complement. The diagnosis of thrombotic microangiopathy (TMA) of primary versus secondary cause is proposed. For religious reasons MAT is treated with Rituximab, adding later Eculizumab. No pathological renal anatomy was performed, nor was plasmapheresis performed for this reason. It required dialytic treatment. ADAMTS XIII was normal and had significant C3 consumption. At 6 months of follow-up, without lupus activity, thrombocytopenia or hemolytic anemia, Rituximab and Eculizumab were discontinued. He continued on chronic dialysis treatment

Síndrome urémico hemolítico atípico recurrente post-trasplante renal: tratamiento con eculizumab / Recurrent atypical hemolytic uremic syndrome after renal transplantation: treatment with eculizumab

El síndrome urémico hemolítico atípico (SUHa) es una entidad rara que se presenta como una microangiopatía trombótica (anemia hemolítica no inmune, trombocitopenia e insuficiencia renal aguda), cuyas lesiones anatomopatológicas típicas son el engrosamiento de las paredes de capilares y arteriolas con trombosis obstructiva del lumen vascular. Se produce por desregulación de la vía alterna del complemento en la superficie celular, debido a causas genéticas o adquiridas, con una alta tasa de mortalidad, enfermedad renal crónica terminal y recurrencia post-trasplante renal. Las mutaciones de peor pronóstico son las asociadas a factor H, factor B y fracción C3 del complemento. La terapia plasmática resulta útil solo en algunos casos, mientras que el uso de eculizumab es altamente eficaz tanto para el tratamiento agudo como para prevenir las recurrencias en el post-trasplante. Comunicamos el caso de una mujer adulta con diagnóstico de SUHa congénito (mutación de C3) en tratamiento preventivo con eculizumab posterior al trasplante renal, sin recurrencia de la enfermedad, ni efectos adversos relacionados al medicamento a los 36 meses de seguimiento post-trasplante.

Atypical hemolytic uremic syndrome (aHUS) is a rare entity. It is characterized by a thrombotic microangiopathy (nonimmune hemolytic anemia, thrombocytopenia, and acute renal failure), with a typical histopathology of thickening of capillary and arteriolar walls and an obstructive thrombosis of the vascular lumen. The syndrome is produced by a genetic or acquired deregulation of the alternative pathway of the complement system, with high rates of end stage renal disease, post-transplant recurrence, and high mortality. Mutations associated with factor H, factor B and complement C3 show the worst prognosis. Even though plasma therapy is occasionally useful, eculizumab is effective both for treatment and prevention of post-transplant recurrence. We describe here an adult case of congenital aHUS (C3 mutation) under preventive treatment with eculizumab after renal transplantation, with neither disease recurrence nor drug-related adverse events after a 36-months follow-up.

Hemolytic uremic syndrome atypical after kidney transplantation: a case report and literature review / Síndrome hemolítico urémico atípico posterior a trasplante renal: presentación de un caso y revisión de la literatura

Abstract Haemolytic uremic syndrome (HUS) is a clinical entity characterized by the appearance of non-immune hemolytic anemia, thrombocytopenia and acute renal failure. It is a disease belonging to the group of thrombotic microangiopathy (MAT) which are part of thrombotic thrombocytopenic purpura also (PTT) and some other MAT associated with other medical conditions formerly known as secondary MAT. Moreover, the variety known as atypical HUS (aHUS) is an ultra-orphan disease that frequently progresses to chronic renal failure (CRF) and is associated with high morbidity and mortality if not properly treated. If a patient presents its first clinical manifestation of aHUS later receive a cadaveric renal transplant which not only makes it an even more exotic case but involves more complexity in their management is presented.

Resumen El síndrome hemolítico urémico (SHU) es una entidad clínica caracterizada por la aparición de anemia hemolítica no inmune, trombocitopenia e insuficiencia renal aguda. Se trata de una enfermedad perteneciente al grupo de las microangiopatías trombóticas (MAT) de la que hacen parte también la purpura trombocitopénica trombótica (PTT) y algunas otras MAT asociadas a otras condiciones médicas antes conocidas como MAT secundarias. Por otra parte, la variedad conocida como SHU atípico (SHUa) es una patología ultra-huérfana que frecuentemente evoluciona a insuficiencia renal crónica (IRC) y se asocia con elevada morbi-mortalidad si no recibe el tratamiento adecuado. Se examina el caso de un paciente que presenta su primera manifestación clínica de síndrome hemolítico urémico atípico después de trasplante renal cadavérico lo cual no solo lo hace un caso aún más exótico, sino que implica mayor complejidad en su manejo.

Compromiso cerebrovascular agudo en síndrome hemolítico urémico: descripción de dos casos pediátricos / Acute cerebrovascular events associated to hemolytic uremic syndrome: description of two pediatric cases

El Síndrome Hemolítico Urémico asociado a diarrea (SHU+D) es un desorden multisistémico en el cual el compromiso neurológico se asocia a empeoramiento del pronóstico. Una causa importante de daño neurológico permanente es el compromiso cerebrovascular. OBJETIVO: Reportar dos casos pediátricos de SHU+D con compromiso neurológico severo debido a patología cerebrovascular y revisar la literatura disponible. CASOS CLÍNICOS: Dos niños de 15 y 21 meses, previamente sanos, debutaron con convulsiones y compromiso de conciencia dentro de la primera semana de un SHU+D. Ambos presentaron hipertensión, falla renal aguda severa y déficit motor focal. Un niño mejoró significativamente su estado neurológico después de cinco sesiones de plasmaféresis. La resonancia magnética encefálica, mostró en el primer niño infartos bilaterales múltiples de vasos pequeños y lesiones de sustancia blanca. En el segundo paciente se identificaron extensos infartos bilaterales en territorios de ambas arterias cerebrales medias. Al año del evento agudo, ambos niños con déficit funcional marcado; el primer paciente evolucionó con retraso del desarrollo del lenguaje y hemiparesia espástica; el segundo persistió con cuadriparesia espástica, epilepsia con mal control de crisis y marcado deterioro funcional. CONCLUSIÓN: Aunque la mayoría de los niños con SHU+D y compromiso cerebral no presentan secuelas a largo plazo, la patología cerebrovascular en el período agudo puede causar daño permanente, por lo que, además del manejo de las alteraciones hidroelectrolíticas, hipertensión y falla renal, las terapias dirigidas a mecanismos fisiopatológicos específicos desencadenantes del compromiso vascular podrían mejorar el pronóstico.

Diarrhea-associated Hemolytic Uremic Syndrome (D+HUS) is a multisystem disorder in which neurological involvement (35 to 50%) is associated to adverse outcome. An important cause of a permanent neurological impairment is the cerebrovascular pathology. OBJECTIVE: To report two pediatric cases of D+HUS with severe neurological involvement due to cerebrovascular disease, and review available literature. CLINICAL CASES: Two previously healthy 15- and 21-month-old children debuted with seizures and impairment of consciousness within the first week of a D+HUS. Both presented hypertension, severe acute renal failure, and focal motor deficit. One child showed significant improvement in neurologic status after five sessions of plasmapheresis. Brain magnetic resonance showed in the first child multiple bilateral infarcts of small vessels and lesions of white matter. In the second patient, large bilateral infarcts on both middle cerebral arteries territories were identified. One year after the acute event, both children showed functional impairment; The first patient evolved with language delay and spastic hemiparesis; the second patient with spastic quadriparesis, epilepsy with poor seizure control and marked functional impairment. CONCLUSION: Although most of the children with D+HUS and brain involvement do not have long-term sequelae, cerebrovascular disease in the acute period causes permanent damage, and in addition to the management of electrolyte disturbances, hypertension, and renal failure, therapies directed at specific pathophysiological mechanisms that trigger vascular compromise may improve prognosis.

Nefropatía por IgA y microangiopatía trombótica / IgA Nephropathy and Thrombotic Microangiopathy

INTRODUCCIÓN: La asociación de microangiopatía trombótica (MAT) y nefropatía por IgA (N.IgA) resulta un hecho conocido, aunque su prevalencia, patogénesis y evolución aún no se han esclarecido. MATERIAL Y MÉTODOS: Se realizó un estudio descriptivo y retrospectivo de 12 pacientes con N.IgA y MAT (N.IgA-MAT), diagnosticadas por biopsia renal en nuestro hospital, para analizar las características clinicopatológicas. Todas las biopsias renales se procesaron para microscopía óptica e inmunofluorescencia. RESULTADOS: La prevalencia de pacientes con N.IgA-MAT fue del 4.4% (12/274). La edad media fue de 33 años y 58.3% eran hombres, con tensión arterial sistólica y diastólica media al momento del diagnóstico de 171.3±53mmHg y 97.5±19.8mmHg respectivamente. La proteinuria promedio resultó 5.3 ± 3.7g/24hs y en 8 pacientes estuvo en rango nefrótico. Se constató deterioro de la función renal en 11 pacientes, con una creatinina sérica media de 7.2±4.7mg/dl. Ningún paciente presentó hallazgos clínicos o de laboratorio sugestivos de microangiopatía trombótica. La biopsia renal mostró MAT aguda con trombos de fibrina arteriolares en el 75% y lesiones crónicas con hiperplasia intimal concéntrica y aspecto de "catáfilas de cebolla" en 83.3%, que se asociaron con un elevado porcentaje de esclerosis glomerular global (72%), atrofia tubular moderada (38.6%) y/o fibrosis intersticial (31.3%). En 91.7% de los casos, la MAT se asoció con grado histológico V. CONCLUSIÓN: La prevalencia y significado de la asociación de N.IgA-MAT nos plantea si la MAT es causa o consecuencia de estadios avanzados de N.IgA. Distintos estudios clinicopatológicos han demostrado que la MAT juega un rol importante en la progresión de la N.IgA. La relación de MAT con los niveles de creatinina sérica y proteinuria apoya su rol en la progresión de la N.IgA. Mientras que las MAT sistémicas cursan con afección de múltiples órganos, en estos casos el riñón fue el único órgano comprometido. La injuria endotelial y subsecuente trombosis microvascular conducen a la isquemia y disfunción renal. El hallazgo de MAT-N.IgA en pacientes con presión arterial normal al momento de la biopsia sugiere que ni la hipertensión ni las lesiones parenquimatosas avanzadas son prerrequisitos para el desarrollo de MAT. Los mecanismos fisiopatológicos que conducen a la injuria endotelial son aún desconocidos, pero parecerían ser distintos a los de la nefropatía hipertensiva maligna

INTRODUCTION: Although the association between thrombotic microangiopathy (TMA) and IgA nephropathy (IgAN) is a known fact, its prevalence, pathogenesis and progression are not clear yet. METHODS: A descriptive, retrospective study involving 12 patients with IgAN and TMA (IgAN-TMA) was carried out; patients were diagnosed by a renal biopsy performed in our hospital in order to analyze clinicopathologic features. All the biopsy samples were processed for light microscopy and immunofluorescence. RESULTS: The prevalence of patients with IgAN-TMA was 4.4% (12/274). The mean age was 33 and 58.3% of the subjects were men, showing, during diagnosis, mean systolic and diastolic blood pressure values of 171.3±53 mmHg and 97.5±19.8 mmHg, respectively. The average amount of protein in urine was 5.3 ± 3.7g/24 h and 8 patients had nephrotic-range proteinuria. Impairment of renal function was found in 11 patients, with a mean serum creatinine level of 7.2±4.7 mg/dL. No clinical or laboratory findings suggested thrombotic microangiopathy in any of the patients. The renal biopsy showed acute TMA with arteriolar fibrin thrombi in 75% of the subjects and 'onion-skin-like' chronic lesions with concentric intimal hyperplasia in 83.3% of them, which were associated with a high percentage of global glomerulosclerosis (72%), moderate tubular atrophy (38.6%) and/or interstitial fibrosis (31.3%). In 91.7% of the cases, TMA was related to histological grade 5. CONCLUSIONS: The prevalence and significance of the relationship between IgAN and TMA pose the question of whether TMA is the cause or consequence of advanced stage IgAN. Several clinicopathologic studies have proved that TMA plays a major role in IgAN progression. The connection of TMA with creatinine serum and proteinuria levels seems to support this conclusion. While systemic TMA usually affects multiple organs, in these cases, the kidney was the only one compromised. Endothelial injury and the subsequent microvascular thrombosis lead to ischaemia and kidney failure. The TMA-IgAN finding in patients with normal blood pressure at the time of the biopsy suggests that neither hypertension nor advanced parenchymal lesions are a prerequisite for the development of TMA. The physiopathological mechanisms leading to endothelial injury are still unknown, but appear to be different from those of malignant nephrosclerosis

Síndrome urémico hemolítico atípico del adulto. Presentación de un caso y revisión de la bibliografía / Atypical hemolytic uremic syndrome in adults. Case report and literature review

El SHUa (Síndrome Hemolítico atípico) se caracteriza por la tríada anemia hemolítica no inmune, trombocitopenia e injuria renal aguda (IRA), en la cual el daño tisular está mediado por una microangiopatía trombótica (MAT). Es una entidad con afectación sistémica, muy poco frecuente, originada en la desregulación del sistema del complemento. Presentamos el caso de una paciente portadora de anemia hemolítica, plaquetopenia, IRA oligoanúrica, cuadro neurológico con evolución tórpida, diagnóstico de SHUa, una revisión bibliográfica, y las sugerencias terapéuticas para esta enfermedad

Atypical hemolytic uremic syndrome (aHUS) consists of the triad of non-immune hemolytic anemia, thrombocytopenia and acute kidney injury (AKI) and is characterized by tissue injury as a result of thrombotic microangiopathy (TMA). It is a very rare systemic disease triggered by complement system dysregulation. This report describes the case of a patient with hemolytic anemia, thrombocytopenia, oligo-anuric AKI, a neurological disorder with torpid course and an aHUS diagnosis. A literature review and therapeutic recommendations for this disease are also presented

Microangiopatía trombótica en una paciente con infección por el virus de la inmunodeficiencia humana / Thrombotic microangiopathy in a patient with human inmunodeficiency virus infection

Notificamos un caso de microangiopatía trombótica, caracterizado por un proceso de agregación plaquetaria amenazante para la vida, que presentó afectación multisistémica y rápida evolución en una paciente con infección por el VIH. En este caso exponemos ampliamente los síntomas, la evolución y, finalmente, la necropsia clínica. Esta enfermedad es ahora infrecuente tras la llegada de los antirretrovirales de gran actividad, no obstante, se presenta con síntomas inespecíficos y evoluciona rápidamente a la afectación multisistémica y muerte. En consecuencia, un diagnóstico precoz con base en criterios clínicos y analíticos es fundamental para instaurar el tratamiento adecuado y mejorar la supervivencia.

We report on a case of thrombotic microangiopathy, defined as an extensive and dangerous intravascular platelet aggregation disorder, which progressed to multisystem involvement in a patient with HIV infection. For this clinical case, we detail the symptoms, evolution and, ultimately, the clinical autopsy. This disease is now uncommon due to the arrival of highactivity antiretroviral drugs; however, it can appear with nonspecific symptoms and rapidly progress to multisystem involvement and death. An accurate diagnosis on the basis of clinical and analytical criteria is essential to starting treatment and improving survival.

Uso do eculizumab na síndrome hemolítica urêmica atípica: relato de caso e revisão da literatura / Eculizumab for the treatment of atypical hemolytic uremic syndrome: case report and revision of the literature

Síndrome Hemolítico Urêmica atípica (SHUa), isto é, não associada à Escherichia coli, produtora de Shiga toxina, é vista em 5% a 10% dos casos de Síndrome Hemolítico Urêmica (SHU), podendo ocorrer em qualquer idade e ser esporádica ou familiar. O prognóstico nestes casos é reservado, com alta mortalidade e morbidade na fase aguda da doença, e cerca de 50% dos casos podem evoluir para doença renal crônica terminal. O aumento do conhecimento da patôgenese da SHUa (hiperativação da via alternativa do complemento) foi acompanhado pelo surgimento de uma droga, eculizumab, a qual age como inibidor da via final do complemento. Nosso objetivo é relatar um caso de lactente com SHUa que apresentou excelente resposta clínica e laboratorial com o uso de eculizumab. Lactente, 14 meses de idade, sexo masculino, previamente hígido, apresentou quadro de anemia e plaquetopenia aos 12 meses de idade. Foi tratado com corticoterapia e encaminhado ao nosso serviço por hipertensão arterial. Entretanto, os exames demonstraram acometimento renal com proteinúria nefrótica e hipoalbuminemia, com Coombs direto negativo. Evoluiu com anemia, plaquetopenia, piora de função renal e hipertensão. Realizada biópsia renal que mostrou microangiopatia trombótica (MAT). Diante do quadro de anemia não hemolítica, plaquetopenia e insuficiência renal aguda com substrato histológico de MAT, foi feito diagnóstico de SHUa. O paciente recebeu eculizumab, com excelente resposta clínico-laboratorial. Este caso denota a importância de diagnóstico e tratamento precoces nesta entidade grave que é a SHUa. Eculizumab é eficaz e mantém remissão a longo prazo, evitando medidas invasivas como a plasmaferese, a qual resolve apenas parcialmente o quadro.

SHU atypical (aHUS), that is, not associated with Escherichia coli Shiga toxinproducing, is seen in 5 to 10% of cases of Hemolytic Uremic Syndrome (HUS), and can occur at any age and may be sporadic or familial. The prognosis in these cases is reserved, with high mortality and morbidity in the acute phase of the disease, and about 50% of cases can develop chronic kidney disease. The increased knowledge of the pathogenesis of aHUS (overactivation of the alternative pathway of complement), was accompanied by the appearance of a drug, eculizumab, which acts as an inhibitor of membrane attack complex. Our goal is to report a case of infant with aHUS with excellent clinical and laboratory response with the use of eculizumab. 14 month old infant, previously healthy, male, presented anemia and thrombocytopenia at 12 months of age. He was treated with corticosteroids and forwarded to our service for high blood pressure. However, the scans showed nephrotic proteinuria with renal involvement and hypoalbuminemia with direct Coombs negative. He developed anemia, thrombocytopenia, worsening of renal function and hypertension. Renal biopsy showed thrombotic microangiopathy (TMA). On the non-hemolytic anemia, thrombocytopenia and acute renal failure with histological substrate MAT, was diagnosed of aHUS. The patient received eculizumab excellent clinical and laboratory response. This case shows the importance of early diagnosis and treatment of the aHUS. Eculizumab is effective and keeps long-term remission, avoiding invasive measures such as plasmapheresis, which resolves only part of the picture.

Púrpura trombocitopénica trombótica: Informe de un caso y revisión de la fisiopatología / Thrombotic thrombocytopenic purpura: A case and review of its physiopathology

Se informa un caso compatible con púrpura trombocitopénica trombótica así como los hallazgos de autopsia con una breve revisión de la literatura. Paciente de 19 años de edad con antecedente de HELLP en su primer embarazo, que cursó con alteraciones neurológicas, trombocitopenia y anemia hemolítica. Falleció a 15 días después de su hospitalización. El estudio posmortem reveló numerosos trombos en los vasos de pequeño calibre de diversos órganos. La púrpura trombocitopénica trombótica es un padecimiento raro cuya expresión morfológica es la formación de microtrombos que obliteran el lecho capilar de diversas estructuras vitales. Moschcowitz fue el primero en informar el hallazgo de múltiples trombos hialinos en los vasos de pequeño calibre en una autopsia parcial. Se consideró la posible existencia de "un veneno con capacidad trombótica y aglutinante", que más tarde se identificó como polímeros ultralargos del factor de Von Willebrand cuya persistencia se debe a la carencia de la metaloproteinasa ADAMTS13.

We report a case compatible with thrombotic thrombocytopenic purpura, autopsy findings and make a brief review of the literature. 19 year old woman with HELLP syndrome in her previous pregnancy who presented with neurological signs, thrombocytopenia and microangiopathic haemolytic anemia until her pass away fifteen days after being admitted to the hospital. Autopsy findings showed multiple thrombi in small sized vessels of several organs. Thrombotic thrombocitopenic purpura is a rare disease with a morphological expression featured of many microthrombi in the terminal arterioles of several vital structures. Moschcowitz was the first to inform multiple hyaline thrombi as the primordial finding of a partial autopsy case. He proposed that "a powerful poison with both agglutinative and hemolytic properties" was the causative agent but it was identified years later as unusually large fragments of Von Willebrand factor caused by a deficiency of ADAMTS13, a newly discovered metalloproteinase.

Microangiopatía trombótica atrombocitopénica: un diagnóstico no realizado con los criterios actuales / Athrombocitopenic thrombotic microangiopathy: diagnosis not performed with the present criteria

Las microangiopatías trombóticas (MAT), que incluyen la púrpura trombótica trombocitopénica (PTT) y al síndrome urémico-hemolítico (SUH), se diagnostican habitualmente por la presencia de anemia hemolítica no inmune y trombocitopenia, lo que lleva a tratarlas con plasmaféresis. Se reporta el caso de una paciente de 51 años que ingresó con insuficiencia renal aguda-subaguda de etiología desconocida cuya biopsia renal mostró microangiopatía trombótica pero sin trombocitopenia ni anemia hemolítica. Por lo tanto dicha patología no siempre seria diagnosticada con los criterios actuales, debiendo utilizarse otros marcadores como ADAMTS-13.

The disease category of thrornbotic microangiopathy (TM) encompass diffcrent entities such as thrombocvtopenic thrombotic purpura (TTP) and uremic hemolytic syndrorne (UHS) , both strongly related and whose diagnosis relies on the presence of non immune hemolytic anemia and trombocytopenia, findings that should urge the caring physician to start plasmapheresis promptly. We report the case of a 51 year old woman admitted with acute-subacute renal failure of unknown etiology whose renal biopsy finding was thrombotic microangiopathy, in absence of thrombocytopenia and haemolytic anemia. This inusual case and according to published literature can not be diagnosed on standard accepted criteria and others markers like ADAMTS-13 should be considered.