Clinicopathological features and prognosis of kidney injury in patients after hematopoietic stem cell transplantation / 中华预防医学杂志

To summarize the clinicopathological features and prognosis of kidney injury after hematopoietic stem cell transplantation (HSCT), to provide basis for preventing its occurrence and development. By using a retrospective cohort study method, we collected the clinical and renal biopsy pathological data of all the patients who hospitalized in the Department of Nephrology of Peking University First Hospital from June 2011 to June 2021 with renal injury after HSCT and underwent renal biopsy, and prognosis was followed up by telephone. The clinical laboratory characteristics, renal pathology and prognosis, and their association were analyzed. The results showed that the most common clinical phenotype was chronic kidney disease (CKD,69.2%, 18/26), in this term 13/18 patients received stem cells from haploidentical donors, and 11/18 patients experienced with extrarenal graft-versus-host disease (GVHD). The most common pathologic phenotype was thrombotic microangiopathy (TMA, 61.5%, 16/26). Renal function returned to baseline level in 6 patients, and the kidney survival at 2 years and 5 years were 95.7% (22/23) and 87.5% (14/16), respectively. In conclusion, the clinical phenotype of renal injury after HSCT were mainly CKD, and the most common pathologic phenotype was TMA, the long-term prognosis was favourable.

Outcomes of allograft from donor kidney microthrombi and secondary recipient thrombotic microangiopathy: should we consider loosening the belt? / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

There is currently a huge worldwide demand for donor kidneys for organ transplantation. Consequently, numerous marginal donor kidneys, such as kidneys with microthrombi, are used to save patients' lives. While some studies have shown an association between the presence of microthrombi in donor kidneys and an increased risk for delayed graft function (DGF) (McCall et al., 2003; Gao et al., 2019), other studies have demonstrated that microthrombi negatively impact the rate of DGF (Batra et al., 2016; Hansen et al., 2018), but not graft survival rate (McCall et al., 2003; Batra et al., 2016; Gao et al., 2019). In contrast, Hansen et al. (2018) concluded that fibrin thrombi were not only associated with reduced graft function six months post-transplantation but also with increased graft loss within the first year of transplantation. On the other hand, Batra et al. (2016) found no significant differences in the DGF rate or one-year graft function between recipients in diffuse and focal microthrombi groups. To date, however, the overall influence of donor kidney microthrombi and the degree of influence on prognosis remain controversial, necessitating further research.

Advances in Diagnosis and Treatment of Transplant-Associated Thrombotic Microangiopathy --Review / 中国实验血液学杂志

Transplantation-associated thrombotic microangiopathy (TA-TMA) is one of the serious complications mostly occurring within 100 days after hematopoietic stem cell transplantation (HSCT). Risk factors of TA-TMA include genetic predispositions, GVHD, and infections. The pathophysiological mechanisms of TA-TMA start with endothelial injury caused by complement activation, which leads to microvascular thrombosis, and microvascular hemolysis, ultimately resulting in multi-organ dysfunction. In recent years, the development of complement inhibitors has markedly improved the prognosis of TA-TMA patients. This review will give an update on risk factors, clinical manifestations, diagnosis, and treatment of TA-TMA, so as to provide references for clinical practice.

Microangiopatía trombótica como complicación de una pancreatitis aguda / Thrombotic microangiopathy as a complication of acute pancreatitis / Microangiopatia trombótica como complicação da pancreatite aguda

La púrpura trombótica trombocitopénica (PTT) es una microangiopatía trombótica poco frecuente, que se caracteriza por anemia hemolítica y plaquetopenia, con una elevada morbimortalidad. Su forma más frecuente es la PTT inmune, también denominada adquirida, provocada por la deficiencia de la enzima disintegrin-like and metalloprotease with thrombospondin type 1 motif 13 (ADAMTS13) secundaria a la presencia en plasma de autoanticuerpos. Presentamos el caso de un paciente con diagnóstico de pancreatitis aguda (PA) complicada con PTT, asociación de presentación excepcional en la práctica clínica.

Summary: Thrombotic thrombocytopenic purpura is rather an unusual thrombotic microangiopathy characterized by hemolytic anemia and plateletopenia which results in high morbimortality rates. The most frequent form of this disease is immune thrombotic thrombocytopenic purpura, also known as acquired thrombotic thrombocytopenic purpura, which is caused by enzime deficiency disintegrin-like and metalloprotease with thrombospondin type 1 motif 13 (ADAMTS13) that is secondary to antibodies in plasma. The study presents the case of a patient with a diagnosis of acute pancreatitis with a rare complication of thrombotic thrombocytopenic purpura which is exceptional in the clinical practice.

A púrpura trombocitopênica trombótica (PTT) é uma microangiopatia trombótica rara, caracterizada por anemia hemolítica e trombocitopenia, com alta morbimortalidade. Sua forma mais comum é a TTP imune, também conhecida como adquirida, que é causada pela deficiência da enzima ADAMTS13 (em inglês A disintegrin-like and metalloprotease with thrombospondin type 1 motif no. 13) secundária à presença de autoanticorpos no plasma. Apresentamos o caso de um paciente com diagnóstico de pancreatite aguda (PA) complicada por PTT, associação com apresentação excepcional na prática clínica.

Clinical characteristics and risk factors of pericardial effusion after hematopoietic stem cell transplantation in children with thalassemia major / 中华儿科杂志

Objective: To investigate the characteristics, risk factors and outcomes of thalassemia major (TM) children with pericardial effusion (PE) after allo-geneic hematopoietic stem cell transplantation (allo-HSCT). Methods: Clinical data of 446 TM children received allo-HSCT at Shenzhen Children's Hospital between January 2012 and December 2020 were analyzed retrospectively. Patients were divided into PE and non-PE group according to the occurrence of PE. Chi-square tests were used to investigate the risk factors that were associated with the development of PE. Kaplan-Meier method was used for survival analysis of the 2 groups. Results: Twenty-five out of 446 patients (5.6%) developed PE at a time of 75.0 (66.5, 112.5) days after allo-HSCT. Among these patients, 22 cases (88.0%) had PE within 6 months after allo-HSCT and 19 patients (76.0%) had PE within 100 days after allo-HSCT. The diagnoses of PE were confirmed using echocardiography. Pericardial tamponade was observed in only 1 patient, who later undergone emergency pericardiocentesis. The rest of patients received conservative managements alone. PE disappeared in all patients after treatment. Risk factors that were associated with the development of PE after allo-HSCT included the gender of patients, the type of transplantation, the number of mononuclear cells (MNC) infuse, pulmonary infection after HSCT and transplantation associated thrombotic microangiopathy (TA-TMA) (χ²=3.99, 10.20, 14.18, 36.24, 15.03, all P<0.05). In 239 patients that received haploidentical HSCT, the development of PE was associated with the gender of patients, pulmonary infection after HSCT and TA-TMA (χ²=4.48, 20.89, 12.70, all P<0.05). The overall survival rates of PE and non-PE groups were 96.0% (24/25) and 98.6% (415/421). The development of PE was not associated with the overall survival of TM children after allo-HSCT (χ²=1.73, P=0.188). Conclusions: PE mainly develop within 100 days after allo-HSCT in pediatric TM recipients. Haploidentical grafts, female gender, pulmonary infection after HSCT and TA-TMA are the main risk factors associated with PE development after transplant. However, the presence of PE don't have a significant impact on the outcomes of pediatric TM patients after allo-HSCT.

Pseudomicroangiopatía trombótica por deficiencia de vitamina B12 en un lactante / Pseudo-thrombotic microangiopathy due to vitamin B12 deficiency in an infant

La seudomicroangiopatía trombótica o síndrome de Moschcowitz es una manifestación infrecuente del déficit de vitamina B12. Se caracteriza por anemia hemolítica con características microangiopáticas, reticulocitos e índices hematimétricos normales o con ligera megaloblastosis, asociados a manifestaciones neurológicas. La vitamina B12 está presente en alimentos proteicos de origen animal. La lactancia materna es una fuente adecuada para los niños cuando los niveles maternos son normales. Se presenta a una paciente de 16 meses que se internó por anemia hemolítica con requerimiento transfusional, plaquetopenia, mal progreso pondoestatural y retraso neuromadurativo. Durante su internación se arribó al diagnóstico de seudomicroangiopatía trombótica secundaria a déficit de vitamina B12.

Pseudo-thrombotic microangiopathy, or Moschcowitz syndrome, is a rare manifestation of vitamin B12 deficiency. It is characterized by microangiopathic hemolytic anemia, reticulocytes, and hematimetric indices that can be normal or that might present a mild megaloblastosis, and which are associated with neurological manifestations. Vitamin B12 can be found in animal-based protein foods. Breastfeeding is an adequate source of this vitamin for children, when maternal serum levels are normal. The case of a 16-month-old infant is presented. She was admitted for hemolytic anemia with transfusion requirement, thrombocytopenia, failure to thrive and developmental delay. During her hospitalization, she was diagnosed with pseudothrombotic microangiopathy caused by vitamin B12 deficiency.

Síndrome hemolítico urémico en una mujer adulta mayor: reporte de caso y revisión de la literatura / Hemolytic uremic syndrome in an older adult woman: case report and literature review

El síndrome hemolítico urémico (SHU) típico en adultos es una patología infrecuente. En la literatura se encuentran pocos reportes, y se ha documentado principalmente en la población pediátrica. Esta entidad se caracteriza por ser una microangiopatía trombótica (MAT) que compromete de manera característica los riñones. Es causada usualmente por la infección por Escherichia coli productora de toxina Shiga (STEC), específicamente el serotipo O157:H7. En Colombia no existen casos reportados sobre esta condición en adultos, lo cual llama la atención, pero puede deberse en parte a las dificultades en su diagnóstico, al no tenerse fácil acceso a algunas de las pruebas que orientan hacia esta enfermedad y confirman el diagnóstico. Se reporta el caso de una mujer adulta mayor colombiana, quien consultó por deposiciones diarreicas y hematoquecia, con el posterior desarrollo de trombocitopenia severa, lesión renal aguda, y evidencia de equinocitos y esquistocitos en extendido de sangre periférica, lo que llevó a sospechar una MAT. Se le solicitó FilmArray® gastrointestinal, el cual fue positivo para STEC, confirmando así el diagnóstico de un SHU típico. Se presenta también una breve revisión del tema de una entidad que requiere un diagnóstico temprano y certero que permita brindar un tratamiento eficaz y oportuno

The classic or typical hemolytic uremic syndrome (HUS) in adults is a rare disease. Few reports are found in the literature, and it has mainly been documented in the pediatric population. This condition is a form of thrombotic microangiopathy (TMA), which characteristically compromises the kidneys. It is mainly caused by infection with Shiga toxin-producing Escherichia coli (STEC), specifically the O157:H7 serotype. In Colombia there are no reports on this condition in adults, and may be due in part to difficulties in its diagnosis, as there is not easy access to some of the tests that guide towards this condition and confirm the diagnosis. The case of an elderly Colombian woman is reported, who presented diarrhea and hematochezia, and subsequently developed severe thrombocytopenia and acute kidney injury, with evidence of echinocytes and schistocytes in peripheral blood smears, which led to suspect TMA. A gastrointestinal FilmArray™ was ordered, which was positive for STEC, thus confirming the diagnosis of a typical HUS. A brief literature review is also presented, which covers general concepts of a condition that requires an early and accurate diagnosis in order to provide an effective and timely treatment

Microangiopatías trombóticas primarias: una revisión narrativa / Primary thrombotic microangiopathies: a narrative review

La microangiopatía trombótica (MAT) es un síndrome donde hay formación de microtrombos en la circulación que llevan a anemia hemolítica microangiopática (AHMA) y trombocitopenia con falla multiorgánica, debido a la isquemia de los tejidos. Las MAT pueden ser primarias sin causa subyacente asociada, como la púrpura trombocitopénica trombótica debida a deficiencia de la enzima ADAMTS13, el síndrome hemolítico urémico debido a la toxina Shiga de Escherichia coli enterohemorrágica, y la MAT producida por alteraciones en la regulación del complemento. Adicionalmente, pueden ser secundarias a enfermedades malignas, infecciosas, metabólicas, autoinmunes o inducidas por el embarazo. Estas patologías requieren diagnóstico y tratamiento oportunos debido a que tienen alta morbimortalidad y se asocian a complicaciones que incluyen enfermedad renal, alteraciones neurológicas como convulsiones, accidente cerebrovascular, coma y muerte. El tratamiento es multidisciplinario y se enfoca en el soporte hemodinámico, transfusional y en el manejo de la etiología cuando esta es identificada. La siguiente revisión pretende explicar de forma clara y precisa los aspectos generales de las MAT primarias

Thrombotic microangiopathy (TMA) is a syndrome characterized by the formation of microthrombi in the circulation leading to microangiopathic hemolytic anemia (MAHA) and thrombocytopenia, with multiorgan failure due to tissue ischemia. TMA can be primary with no associated underlying cause, such as thrombotic thrombocytopenic purpura due to ADAMTS13 deficiency, hemolytic uremic syndrome due to the Shiga toxin from enterohemorrhagic Escherichia coli, or due to complement dysregulation. Furthermore, TMA can be secondary to malignant, infectious, metabolic or autoimmune diseases, or induced by pregnancy. These conditions require a timely diagnosis and treatment due to their associated high morbidity and mortality, and complications like renal disease, neurological disorders such as seizures, stroke, coma and death. Treatment is multidisciplinary and focuses on hemodynamic and transfusion support, and on the management of the etiology when it is identified (daily plasma exchange, eculizumab or management of underlying disease). This review aims to discuss the general aspects of primary thrombotic microangiopathies

Biomarcadores y blancos moleculares del complemento en el diagnóstico de las microangiopatías trombóticas / Complement biomarkers and molecular targets in the diagnosis of thrombotic microangiopathies / Biomarcadores e alvos moleculares do complemento no diagnóstico das microangiopatias trombóticas

Resumen El sistema del complemento juega un papel central en la inmunidad innata, es una línea de defensa contra patógenos y participa en la homeostasis. La activación anormal del complemento contribuye al desarrollo de patologías de variable severidad, tanto inmunológicas y hematológicas como renales. Entre ellas, las microangiopatías trombóticas (MAT) representan un grupo de enfermedades raras con manifestaciones clínicas comunes caracterizadas por anemia hemolítica no inmune, trombocitopenia y daño de órgano(s) blanco. Si bien la clasificación de las MAT sigue siendo desafiante y no ha sido internacionalmente estandarizada, la descripción de entidades asociadas a anomalías del complemento fue comprobada con la eficiencia de la terapia anticomplemento en los pacientes. Las herramientas de diagnóstico desarrolladas en las últimas décadas son esenciales actualmente para diferenciar las MAT más características del grupo; esto es, la púrpura trombótica trombocitopénica (PTT) y el síndrome urémico hemolítico (SUH). En el presente trabajo se presenta una revisión del funcionamiento del sistema del complemento en condiciones fisiológicas, para poder explicar luego cuáles son las alteraciones del sistema implicadas en el desarrollo de las MAT y describir las herramientas disponibles para detectarlas en el laboratorio.

Abstract The complement system plays a crucial role in the innate immune response, being the first-line defense against pathogens and regulating homeostasis. Uncontrolled complement activation can cause immunologic, hematologic as well as renal syndromes of variable severity. Among them, thrombotic microangiopathies (TMA) represent a group of rare diseases characterised by similar clinical manifestations such as microangiopathic hemolytic anemia (MAHA), peripheral thrombocytopenia and organ injury. Although TMA classification is still challenging and no international consensus has been reached, complement-associated disorders have been described thanks to the efficiency of anti-complement therapy in patients. Diagnostic tools developed in the last decades are essential to differentiate the two most well characterized TMA: thrombotic thrombocytopenic purpura (TTP) and hemolytic uremic syndrome (HUS). This review will describe how the complement system works in physiological conditions in order to explain how complement abnormalities are involved in TMA, and finally how to detect those anomalies using laboratory tests.

Resumo O sistema do complemento desempenha um papel central na imunidade inata, sendo uma linha de defesa contra patógenos e participando da homeostase. A ativação anormal do complemento contribui para o desenvolvimento de patologias de gravidade variável, como imunológicas, hematológicas e renais. Entre elas, as microangiopatias trombóticas (MAT) representam um grupo de doenças raras com manifestações clínicas comuns caracterizadas por anemia hemolítica não imune, trombocitopenia e lesão de órgão(s) alvo. Embora a classificação das MAT continue sendo desafiadora e não tenha sido padronizada internacionalmente, a descrição de entidades associadas a anomalias do complemento foi comprovada com a eficiência da terapia anticomplemento nos pacientes. As ferramentas de diagnóstico desenvolvidas nas últimas décadas são atualmente essenciais para diferenciar as MAT mais características do grupo, que são a púrpura trombocitopênica trombótica (PTT) e a síndrome hemolítica urêmica atípica (SHU). Neste trabalho, é apresentada uma revisão do funcionamento do sistema de complemento em condições fisiológicas, a fim de explicar posteriormente quais são as alterações do sistema compreendidas no desenvolvimento das MAT, e descrever as ferramentas disponíveis para detectá-las em laboratório.

Coronavirus 229E with Rhinovirus co-infection causing severe acute respiratory distress syndrome with thrombotic microangiopathy and death during Covid-19 pandemic: lessons to be learnt

We report on a 3-month old infant male who had a seven-days history of fever and rhinorrhea associated with wheezing prior to his death, during the Covid-19 pandemic. Viral testing for Covid-19 (SARS-CoV-2) was negative but was positive for Coronavirus 229E and RP Human Rhinovirus. The pulmonary histological examination showed diffuse alveolar damage along with thrombotic microangiopathy affecting alveolar capillaries. Also, thrombotic microangiopathy was evident in the heart, lungs, brain, kidneys and liver. Thrombotic microangiopathy is a major pathologic finding in Acute Respiratory Distress Syndrome and in the multiorgan failure. This is the first report that illustrates thrombotic microangiopathy occurring in lung, heart, liver, kidney and brain in Acute Respiratory Distress Syndrome with Coronavirus 229E with Rhinovirus co-infection. The clinical presentation and pathological findings in our case share common features with Covid-19.

Livedoid Vasculopathy: diagnosis and treatment in pregnant women / Vasculopatia livedoide: diagnóstico e tratamento em mulher grávida

Abstract Livedoid Vasculopathy is a disease characterized by occlusion of the capillaries of the dermis, without inflammatory signs. It begins with purpuric papules or macules that develop into painful ulcers, mainly involving the ankles and feet. In this case report, we describe diagnosis and treatment in a young pregnant patient, with excellent clinical response.

Resumo A vasculopatia livedoide é uma doença caracterizada pela oclusão dos capilares da derme, sem sinais inflamatórios. Tem início com pápulas ou máculas purpúricas que evoluem para úlceras dolorosas, com predominância na topografia de tornozelos e pés. Neste relato de caso, descrevemos o diagnóstico e a terapêutica em uma paciente jovem gestante, com excelente evolução clínica.

Atypical hemolytic-uremic syndrome (aHUS) / Síndrome hemolítico urémico atípico (SHUa)

Abstract Atypical hemolytic-uremic syndrome (aHUS) is a diagnosis of exclusion which should be proposed in cases where there is microangiopathic hemolytic anemia, thrombocytopenia and acute kidney injury. It is associated with mutations which cause dysregulation of the complement system and implies an adverse prognosis and a high risk of progression to chronic kidney disease. Following, we present the case of a patient with aHUS, highlighting the effect and importance of biologic therapy with the monoclonal antibody eculizumab. (Acta Med Colomb 2019; 44. DOI:https://doi.org/10.36104/amc.2019.1301).

Resumen El síndrome hemolítico urémico atípico (SHUa) constituye un diagnóstico de exclusión que debe plantearse ante la presencia de anemia hemolítica microangiopática, trombocitopenia y lesión renal aguda. Está asociado con mutaciones que provocan una disregulación del sistema del complemento e implica un pronóstico adverso y alto riesgo de progresión a enfermedad renal crónica. A continuación, presentamos el caso de un paciente con SHUa resaltando el efecto e importancia de la terapia biológica con el anticuerpo monoclonal eculizumab. (Acta Med Colomb 2019; 44. DOI:https://doi.org/10.36104/amc.2019.1301).

Plasmic score applicability for the diagnosis of thrombotic microangiopathy associated with ADAMTS13-acquired deficiency in a developing country

ABSTRACT Background: Thrombotic thrombocytopenic purpura (TTP) is a potentially fatal disease that requires early diagnosis and treatment that can be made possible by applying the PLASMIC score. This study aims to evaluate this score applicability for patients with suspected TTP in a developing country. Methods: This was a retrospective study performed at a tertiary hospital in the northeastern region of Brazil. Patients were analyzed in two groups: ADAMTS13 activity <10% and activity >10%. Patients were stratified according to the PLASMIC score, and the level of agreement between the PLASMIC score and the ADAMTS13 activity was evaluated. Results: Eight patients with thrombotic microangiopathy were included. Four patients had ADAMTS13 activity <10%, all with a PLASMIC score =6. The other four had ADAMTS13 activity >10%, all with a score <6. Based on a score =6 for presumptive diagnosis of TTP, we attained a 100% diagnostic accuracy in our sample. The PLASMIC score was also able to accurately predict response to plasma exchange and the risk of long-term unfavorable outcomes. Conclusions: The reproducibility of the PLASMIC score was quite satisfactory in our sample. It accurately discriminates between patients who had ADAMTS13 deficiency and those with normal enzyme activity, precluding the need for specific laboratory evaluation, which is not always available. This score can be useful for an early diagnosis and indicates which patients will benefit from the treatment in developing countries.

Vasculopatia livedoide tratada com rivaroxabana / Livedoid vasculopathy treated with rivaroxaban

A vasculopatia livedoide é uma doença rara caracterizada pela oclusão da microvasculatura da derme, originando lesões maculosas que, posteriormente, podem evoluir para úlceras e cicatrizes atróficas. Como um fenômeno vaso-oclusivo, o tratamento geralmente é realizado com antiplaquetários e fibrinolíticos. O presente relato descreve o caso de uma paciente refratária à terapia convencional, que obteve regressão da doença utilizando a rivaroxabana, um fármaco inibidor seletivo do fator Xa. (AU)

Livedoid vasculopathy is a rare disease characterized by occlusion of the dermis microvasculature, leading to spotted lesions that can later develop into ulcers and atrophic scars. As a vaso- occlusive phenomenon, treatment is usually performed with antiplatelet and fibrinolytic agents. The present report describes the case of a female patient refractory to conventional therapy who presented disease remission using rivaroxaban, a selective factor Xa inhibitor drug. (AU)

Renal histological findings in a patient with acute renal injury associated with purpura fulminans: a case report / Achados histológicos renais em paciente com injúria renal aguda associada à purpura fulminans: relato de caso

ABSTRACT Introduction: Purpura fulminans (PF) is a rapid progressive thrombotic disease in which hemorrhagic infarction of the skin and disseminated intravascular coagulation (DIC) occurs. It can potentially cause acute kidney injury (AKI). However, there is no description in the medical literature of renal histological findings of PF. Case report: A 20-year-old female patient, previously healthy, was admitted to the emergency department (ED) with odynophagia, fever, generalized myalgia and anuria, which evolved with the appearance of purpuric plaques on the face and limbs. She required dialysis on admission. Laboratorial tests showed anemia, leukocytosis, thrombocytopenia, and elevation of lactic dehydrogenase (LDH). The purpuric lesions became bullous with ruptures and then necrotic and erosive, reaching the dermis, subcutaneous tissue and musculature, until bone exposure. There was no improvement with initial antibiotic therapy aimed at the treatment of meningococcemia. Thrombotic microangiopathy (TMA) and PF were then suspected. The patient remained in daily dialysis, requiring plasmapheresis. After sustained improvement of the thrombocytopenia, she underwent renal biopsy, which was not compatible with TMA, characterizing possible PF. A complete recovery of the renal function was achieved and cutaneous sequels were treated with grafts. Conclusion: When thrombotic and hemorrhagic phenomena overlap, obtaining a renal biopsy can be difficult. However, in the presented case, the biopsy allowed the exclusion of AKI caused by TMA, presenting for the first time, histological findings compatible with PF.

RESUMO Introdução: Purpura Fulminans (PF) é uma doença trombótica de rápida progressão, com infarto hemorrágico da pele e coagulação intravascular disseminada (CIVD). É potencialmente causadora de injúria renal aguda (IRA). Porém, não há descrição na literatura médica dos achados histológicos renais causados por PF. Relato de caso: Mulher, 20 anos, previamente hígida, hospitalizada por odinofagia, febre, mialgia generalizada e anúria, evoluiu com aparecimento de placas purpúricas em face e membros. Necessitou de hemodiálise (HD) já na admissão. Exames laboratoriais mostravam anemia, leucocitose, plaquetopenia e elevação de desidrogenase lática. As lesões purpúricas tornaram-se bolhosas com rompimento e progressão para necrose, se aprofundaram, atingindo derme, subcutâneo e musculatura, até a exposição óssea. Não houve melhora com antibioticoterapia inicial voltada para tratamento de meningococemia. Suspeitou-se, então, de microangiopatia trombótica (MAT) e PF. A paciente permaneceu em HD diária e necessitou também de plasmaférese, após melhora sustentada da plaquetopenia, foi submetida à biópsia renal, que não foi compatível com MAT, possivelmente caracterizando PF. Houve recuperação completa da função renal e as sequelas cutâneas foram tratadas com enxerto. Conclusão: Em casos nos quais os fenômenos trombóticos e hemorrágicos se sobrepõem, a obtenção da biópsia renal se torna difícil. Neste caso, a biópsia permitiu excluir IRA causada por MAT e mostrar, pela primeira vez, achados compatíveis com PF.

Therapeutic Plasma Exchange in a Patient with Hemophagocytic Lymphohistiocytosis

A 22-year old female patient with systemic lupus erythematosus presenting microangiopathic hemolytic anemia was treated with therapeutic plasma exchange 23 times. The patient's condition and laboratory findings (aspartate aminotransferase, alanine aminotransferase, ferritin, total bilirubin, and lactate dehydrogenase) did not improve despite the initial 18 therapeutic plasma exchange treatments. Thrombotic thrombocytopenic purpura was ruled out due to normal ADAMTS-13 activity test result; hemophagocytic lymphohistiocytosis was diagnosed based on fever, splenomegaly, pancytopenia, hypertriglyceridemia, hyperferritinemia, and hemophagocytosis in bone marrow aspiration. The patient's condition improved rapidly upon treatment with a combination of immunosuppressants and cytotoxic agents, and more therapeutic plasma exchanges were performed five consecutive times with prolonged intervals in between. We observed that therapeutic plasma exchange treatment alone was not effective enough to treat hemophagocytic lymphohistiocytosis, unlike thrombotic thrombocytopenic purpura. Therefore, it is necessary to determine and start drug administration promptly in the treatment of hemophagocytic lymphohistiocytosis with thrombotic microangiopathy.

Atypical Hemolytic Uremic Syndrome in a 13-year-old Lao Girl: A Case Report

Atypical hemolytic uremic syndrome (aHUS), a rare form of thrombotic microangiopathy, is distinguished from the typical form by the absence of a preceding verotoxin-producing Escherichia coli infection. Notably, aHUS occurs in association with genetic or acquired disorders causing dysregulation of the alternative complement pathway. Patients with aHUS may show the presence of anti-complement factor H (CFH) autoantibodies. This acquired form of aHUS (anti-CFH-aHUS) primarily affects children aged 9–13 years. We report a case of a 13-year-old Lao girl with clinical features of aHUS (most likely anti-CFH-aHUS). The initial presentation of the patient met the classical clinical triad of thrombotic microangiopathy (microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury) without preceding diarrheal illness. Low serum levels of complement 3 and normal levels of complement 4 indicated abnormal activation of the alternative complement pathway. Plasma infusion and high-dose corticosteroid therapy resulted in improvement of the renal function and hematological profile, although the patient subsequently died of infectious complications. This is the first case report that describes aHUS (possibly anti-CFH-aHUS) in Laos.