Uso de antidepresivos en niños y riesgo de suicidio: una revisión / Use of antidepressants in children and risk of suicide: a review

Introducción: Los trastornos depresivos en la adolescencia tienen una incidencia del 10% y se asocian con significativa comorbilidad. Los ISRS son un tratamiento efectivo que se prescribieron ampliamente en la década de los 90. El hallazgo de una relación entre el uso de antidepresivos y un incremento del riesgo de suicidio entre la gente joven ha generado una gran controversia en los últimos años. Objetivo: Evaluar al riesgo asociado al uso de antidepresivos en la infancia en relación con la ideación suicida. Método: Revisamos la situación actual de la investigación en el campo de la terapia antidepresiva en niños y adolescentes. Se han revisado datos de estudios randomizados aparecidos en publicaciones médicas de los cinco últimos años. Se discuten aspectos metodológicos e implicaciones clínicas de los mismos. Resultados: Se han encontrado diez artículos a propósito del uso de fármacos antidepresivos en relación con el riesgo de conducta suicida. Cuatro de ellos sugieren que los antidepresivos previenen el suicidio, mientras que otros cuatro indican que el riesgo de conductas suicidas se incrementa con el uso de estos fármacos. Dos estudios no muestran resultados significativos. Conclusión: Sería necesario realizar estudios específicos acerca de este tema, ya que los existentes no muestran resultados concluyentes. No obstante, los trastornos depresivos deben ser tratados, dada su elevada prevalencia y su alta comorbilidad (AU)

Introduction: Depressive disorders during youth occur frequently (10%) and are associated with significant comorbidity. ISRS are an effective treatment that was prescribed widely across 1990´s. The finding of a relation between the use of antidepressants and an increase of suicidal risk in young people has generated a great controversy in the last years. Objective: To evaluate the risk of the antidepressant use in childhood in relation to the suicidal ideation. Method: We review the current state of research into antidepressant therapy in children and adolescents. Data from randomised controlled trials published in medical journals in the last five years were reviewed; we discuss methodologic issues and clinical implications. Results: We have found ten trials that treated about antidepressants and suicidal risk. Four of them suggest that antidepressants protect of suicide, whereas four of them indicated that the risk of suicidal behaviour is increased with antidepressant use. Two studies don´t show significant results (AU)

[Effects of parenteral glutamine in patients submitted to bone marrow transplantation]. / Efectos de la glutamina parenteral en pacientes sometidos a trasplante de médula ósea.

UNLABELLED: Bone marrow transplantation (BMT) is a therapy used for hematologic malignancies and solid tumors. Associated chemotherapy and radiotherapy to which these patients are submitted induce secondary effects, with a high metabolic stress. Glutamine is considered a conditionally essential amino acid, and has been shown effective in severe catabolic states. The aim of the study was to assess the effect of parenteral nutrition (PN) therapy supplemented with glutamine on duration of nutritional support in a group of patients with BMT. We have also analyzed associated complications, the nutritional status, the clinical course at 6 months, differences as to type of transplantation, and oral ingestion capability. This is a phase IV, randomized, double blind, and parallel clinical trial, done at a single center. The study was performed on 49 patients, 29% male and 71% female patients, with ages between 21-63 years, distributed in 3 diagnostic groups (leukemia, lymphoma, and solid tumors), and admitted to the Hematology Department of our Hospital. Fifty percent of the patients in each group have received PN supplemented with glutamine (0.4 g/kg/day of L-alanine-L-glutamine), and the other 50% have received standard PN. RESULTS: we have not found significant differences nor at the beginning nor at the end of the study between both groups with regards to studied variables. CONCLUSIONS: PN is and effective therapy for maintenance of the nutritional status in patients submitted to a therapy with a, highly catabolic effect such as BMT. Although we have not been able to show the efficacy of glutamine supplementation in this study with the used dose, it does have been effective in other reports.

Factores de riesgo de suicidio en niños y adolescentes: una revisión bibliográfica / Suicide risk factors in childhood and adolescence: A review

Introducción: el suicidio es la segunda o tercera causa de mortalidad en adolescentes, constituye, por su frecuencia y los años de vida perdidos, un serio problema de salud pública. Objetivos: la finalidad de este estudio es conocer los factores de riesgo asociados con suicidio en adolescentes, para identificarlos y prevenir el riesgo de mortalidad por esta razón. Método: hemos buscado en la base de datos PubMed revisiones sistemáticas publicadas los últimos 5 años en revistas de impacto y algunos de los artículos citados en las mismas. Resultados: los factores asociados con alto riesgo de suicidio son: sexo masculino, mayor edad (15-24 años), dificultades socioeconómicas y experiencias traumáticas en la infancia (hogar disfuncional, abusos sexuales...), psicopatología o suicidio en los padres, enfermedad psiquiátrica (trastorno depresivo y abuso de sustancias), antecedentes de autolesión y vulnerabilidad psicológica a acontecimientos vitales adversos, con importante influencia sociocultural. Discusión: los factores de riesgo de suicidio están a menudo interrelacionados, algunos de ellos constituyen un factor de riesgo independiente, otros favorecen la aparición o refuerzan el efecto de estos (AU)

Introduction: The suicide is the second or third cause of mortality in teenagers. It represents, for its frequency and the lost of life´s years, a serious problem of public health. The aim of the present study is to know the risk factors associated with suicide in adolescents, to be able to identify them and to avoid the mortality by this reason. Method:We searched for systematic reviews in PubMed database published in the last 5 years in core clinical journals, and for some of the articles cited in them. Results: The factors associated with high risk of suicide are: male sex, older age (15-24 years), socioeconomic difficulties and traumatic experiences during childhood (sexual abuses...), parental psychopathology or suicide, psychiatric illness (depressive disorder and substance abuse), previous self-harm and psychological vulnerability to adverse life events, with important socio-cultural influence. Discussion: Risk factors are often linked, some of them are independent risk factors of suicide, and others increase the chance of appearance or reinforce the effect of them (AU)

[Study of renal function and compensatory changes in children with single kidney]. / Determinación de función renal y cambios compensadores en niños con riñón único.

INTRODUCTION: It has always been thought that a reduction of renal tissue in childhood sometimes causes some irreversible injury in the remnant kidney as the years go by. The aim of this paper is to look over the presence of these changes and identify the risk of nephropaty throughout several parameters. MATERIAL AND METHODS: We reviewed 38 children, 23 males and 15 females, aged between 1 and 15 years, who had lost unilateral renal mass because of congenital or adquired diseases. We made two groups of patients on the basis of having born without any unilateral renal function -group I- or having lost unilateral renal function after the second year of life. We measured: Somatometry, arterial pressure, glomerular filtration, microalbuminuria, renal volume and gammagraphic studies were also made. We also considered the presence of contralateral anomalies. RESULTS: Body weight and height were within normal percentiles. Arterial pressure increased in 5 patients. Seric creatinine was normal, creatinine clearance (Ccr) was higher than normal in all patients of both groups, and urinary excretion of protein was normal. Renal volume of remnant kidney was similar in both groups, and no relation with renal function level was found, but it increased through the years. Isotopic studies showed ectatic drainage in all urinary systems. Contralateral anomalies were seen in 7 patients, and they consisted in hydronephrosis and vesico-ureteral reflux. CONCLUSIONS: Hypertension was not related to the cause of renal absence nor the pathology of remnant kidney. Ccr was higher than normal, showing an hyperfiltration status, not confirmed by the values of isotopic filtrate. Renal volume reached by the single kidney was affected by the time after the renal loss, and apparently has been slowed down in cases with contralateral anomalies.

Determinación de función renal y cambios compensadores en niños con riñón único / Study of renal function and compensatory changes in children with single kidney

Introducción. Se ha considerado siempre que la reducción de la masa renal durante la infancia, causa una serie de cambios funcionales que eventualmente pueden conducir a un daño irreversible en el riñón remanente con el paso de los años. Objetivos. La evidencia de estas lesiones en múltiples publicaciones nos movió a revisar a un grupo de 38 pacientes monorrenos en la edad infantil y a intentar determinar el riesgo de aparición de las mismas a través de parámetros como la función renal, la tensión arterial, la presencia de proteinuria y el volumen renal. Material y métodos. Se estudiaron 38 pacientes, 23 de ellos varones y 15 mujeres, de edades entre 1 y 13 años, que habían sufrido pérdida de masa renal por causas congénitas o adquiridas. Se separaron en dos grupos de enfermos: Grupo I: Ausencia congénita unilateral de riñón funcionante (25 casos). Grupo II: Nefrectomizados por pérdida de un riñón(con función previa normal) después del segundo año de vida (13 casos). Se midió la somatometría, la tensión arterial (TA), el filtrado glomerular (FG), la proteinuria, el volumen renal (VR) y se consideró la presencia de anomalías contralaterales (AC). Resultados. El peso y la talla se encontró en percentiles normales. La TA se encontró elevada en 5 pacientes. La creatinina sérica sólo estaba elevada en 1 paciente con severa afectación del riñón remanente, el aclaramiento de creatinina (Ccr) resultó elevado de forma generalizada y se observó microalbuminuria en 2 pacientes. El volumen renal fue similar en ambos grupos. El estudio isotópico evidenció ectasia sin obstrucción en el 80% de todos los casos y el FG según el método de Inoue (corregido para niños) resultó en ambos grupos dentro de valores normales. Conclusiones. No encontramos diferencias significativas en la función renal entre los dos grupos de pacientes ni tampoco indicios de nefropatía por hiperfiltración. El Ccr evidenció una situación de hiperfiltrado en todos los casos. El filtrado glomerular calculado por estudio isotópico no confirmó estasituación. El volumen renal no se observó relacionado con la edad a la que se produjo la pérdida renal, y sí con el tiempo transcurrido postpérdida. La existencia de anomalías en el riñón contralateral influye en el grado de hipertrofia que desarrolla (AU)

Introduction. It has always been thought that a reduction of renal tissue in childhood sometimes causes some irreversible injury in the remnant kidney as the years go by. The aim of this paper is to look over the presence of these changes and identify the risk of nephropaty throughout several parameters. Material and methods. We reviewed 38 children, 23 males and 15 females, aged between 1 and 15 years, who had lost unilateral renal mass because of congenital or adquired diseases. We made two groups of patients on the basis of having born without any unilateral renal function –group I– or having lost unilateral renal function after the second year of life. We measured: Somatometry, arterial pressure, glomerular filtration, microalbuminuria, renal volume and gammagraphic studies were also made. We also considered the presence of contralateral anomalies. Results. Body weight and height were within normal percentiles. Arterial pressure increased in 5 patients. Seric creatinine was normal, creatinine clearance (Ccr) was higher than normal in all patients of both groups, and urinary excretion of protein was normal. Renal volume of remnant kidney was similar in both groups, and no relation with renal function level was found, but it increased through the years. Isotopic studies showed ectatic drainage in all urinary systems. Contralateral anomalies were seen in 7 patients, and they consisted in hydronephrosis and vesico-ureteral reflux. Conclusions. Hypertension was not related to the cause of renal absence nor the pathology of remnant kidney. Ccr was higher than normal, showing an hyperfiltration status, not confirmed by the values of isotopic filtrate. Renal volume reached by the single kidney was affected by the time after the renal loss, and apparently has been slowed down in cases with contralateral anomalies Introduction. It has always been thought that a reduction of renal tissue in childhood sometimes causes some irreversible injury in the remnant kidney as the years go by. The aim of this paper is to look over the presence of these changes and identify the risk of nephropaty throughout several parameters. Material and methods. We reviewed 38 children, 23 males and 15 females, aged between 1 and 15 years, who had lost unilateral renal mass because of congenital or adquired diseases. We made two groups of patients on the basis of having born without any unilateral renal function –group I– or having lost unilateral renal function after the second year of life. We measured: Somatometry, arterial pressure, glomerular filtration, microalbuminuria, renal volume and gammagraphic studies were also made. We also considered the presence of contralateral anomalies. Results. Body weight and height were within normal percentiles. Arterial pressure increased in 5 patients. Seric creatinine was normal, creatinine clearance (Ccr) was higher than normal in all patients of both groups, and urinary excretion of protein was normal. Renal volume of remnant kidney was similar in both groups, and no relation with renal function level was found, but it increased through the years. Isotopic studies showed ectatic drainage in all urinary systems. Contralateral anomalies were seen in 7 patients, and they consisted in hydronephrosis and vesico-ureteral reflux. Conclusions. Hypertension was not related to the cause of renal absence nor the pathology of remnant kidney. Ccr was higher than normal, showing an hyperfiltration status, not confirmed by the values of isotopic filtrate. Renal volume reached by the single kidney was affected by the time after the renal loss, and apparently has been slowed down in cases with contralateral anomalies (AU)

[Acute lobar nephronia. Report of 3 new cases]. / Nefronía lobar aguda. Aportación de tres nuevos casos.

We present three patients, aged 4, 6 and 8 years old, with a diagnosis of urinary tract infection. In all patients, initial ultrasonographic studies revealed a single area of acute lobar nephronia (ALN). The patients underwent renal scintigraphy with dimercaptosuccinic acid-99mTc (DMSA Tc 99m), which showed multiple foci with below normal uptake in both kidneys of two patients, consistent with bilateral multifocal bacterial nephritis. Although this entity has been reported together with ALN in adults, very few pediatric cases have been reported. We emphasize the diagnostic value of ultrasonography and renal scintigraphy.

Autologous peripheral blood stem cell transplant in patients previously diagnosed with invasive aspergillosis.

Patients previously diagnosed with invasive aspergillosis (IA) have been considered to be at risk for relapse of mycosis during subsequent hematopoietic transplant. Even with prophylactic measures, reactivation of the infection occurs in 29% of patients undergoing bone marrow transplantation (BMT). A period of neutropenia is one of the variables considered to be a risk factor for reactivation. Peripheral blood stem cell transplant (PBSCT) results in a shorter neutropenia period leading to a lower risk of fungal infection. A retrospective data analysis performed on patients undergoing autologous PBSCT for hematological malignancies in our unit showed that nine patients were diagnosed before transplantation with IA. All patients received only medical treatment during their primary infection. Medical prophylaxis was administered in seven of these patients, and two underwent transplantation without prophylaxis. All patients developed severe neutropenia after a myeloablative regimen. All but one had neutropenic fever, although the fever was controlled and no fungal complications occurred. All patients in this series achieved complete hematological engraftment without delay in granulocyte recovery (mean: 8.78 vs 9.76; p=0.58). No significant differences were observed in toxicities with regards to transplantation between patients previously diagnosed with IA and their controls. Recurrence of IA related to transplantation was avoided since no relapse of IA was demonstrated. This series of nine patients with a previous history of IA shows that medical treatment, secondary prophylaxis, and peripheral blood as a source of stem cells could be effective measures to avoid reactivation of previous aspergillosis during hematopoietic transplantation, although prospective randomized trials should still be performed to confirm these findings in a wider setting.

Hipomagnesemia familiar con hipercalciuria y nefrocalcinosis / Familial hypermagnesemia with hypercalciuria and nephrocalcinosis

La hipomagnesemia familiar con hipercalciuria y nefrocalcinosis es un síndrome poco frecuente que pertenece a un grupo de tubulopatías de naturaleza heterogénea, cuya característica común es la pérdida urinaria de magnesio. Se presenta el caso de un niño de 9 años de edad con sintomatología de poliuria, polidipsia y enuresis. Existía nefrocalcinosis ecográfica y radiológica. Se encontró hipomagnesemia, normopotasemia, hipermagnesiuria, hipercalciuria, acidosis tubular distal incompleta, hipocitraturia e insuficiencia renal leve. El tratamiento con sales de magnesio, hidroclorotiacida, citrato potásico y bicarbonato sódico no ha conseguido normalizar ni la magnesiuria ni la calciuria. La función renal y la nefrocalcinosis permanecen estables tras 3 años de control. Se trata de un nuevo caso de este raro síndrome producido por un defecto congénito de la resorción tubular de magnesio, y su evolución clínica y analítica tras 3 años de seguimiento (AU)

[Technetium-99m-dimercaptosuccinic acid (DMSA) scintigraphy in the first febrile urinary tract infection in children]. / Gammagrafía con tecnecio-99m-ácido dimercaptosuccínico en el estudio de la primera infección urinaria febril del niño.

OBJECTIVE: The objective of this study was to evaluate the findings of 99mTc-DMSA renal scintigraphy in children with their first acute febrile urinary tract infection in relation with several clinical-biological parameters and other imaging studies and a long-term follow up. MATERIAL AND METHODS: 103 children between 1 month and 10 years old with their first acute febrile urinary tract infection were studied by means of clinical and laboratory assessment, renal ultrasonography and 99mTc DMSA renal scintigraphy in the acute illness period. Patients were divided into two groups, those under 2 years old (n = 63) and those over 2 years old (n = 40). RESULTS: Cortical scintigraphy showed renal changes in 56 patients (54,5%). Children over 2 years of age had a higher incidence of renal lesions than younger children (39,7% vs. 77,5%). Ultrasonography measuring renal volume showed a simple concordance with scintigraphy in 64% of the patients. Reflux was demonstrated in 23 patients (22,3%) without differences between patients with normal or abnormal cortical scintigraphy. After having studied the factors that were associated independently to the pathological results in the scintigraphy through a logistical multivariant regression, it was observed that the child's age, the elevation of the PCR and the alterations of the renal volume were significant according to statistics and also associated to a larger amount of pathological DMSA scintigraphy. CONCLUSIONS: DMSA scintigraphy associated with other diagnostic methods can improve the sensitivity and specificity to establish renal damage stage. During the follow-up the acute lesions disappeared or improved in all cases and the chronic lesions have not been modificated.

Factors influencing collection and engraftment of CD34+ cells in patients with breast cancer following high-dose chemotherapy and autologous peripheral blood progenitor cell transplantation.

Although autologous PBPC transplantation is being used increasingly for the treatment of breast cancer, there are few data on factors influencing mobilization and engraftment in these patients. We have analyzed these factors in 70 patients with advanced or metastatic breast cancer undergoing autologous PBPC transplantation. All patients were mobilized after stimulation with G-CSF, and a median of 3.16 x 10(6)/kg CD34+ cells (range 0.75-23.33) were infused. All patients received conditioning with a combination of cyclophosphamide, thiotepa, and carboplatin, and postinfusion G-CSF was administered to 60 patients. The median times to reach 0.5 x 10(9)/L and 1 x 10(9)/L neutrophils were 10 and 11 days, respectively. The median times to obtain 20 x 10(9)/L and 50 x 10(9)/L platelets were 12 and 18 days, respectively. An analysis of factors that influence CD34+ cell collection was performed by linear regression. Previous radiation therapy and increasing age were associated with lower numbers of CD34+ cells collected. Those variables that could influence the tempo of engraftment were examined by multivariate analysis using Cox regression models. The number of CD34+ cells infused was found to influence both neutrophil and platelet recovery. The use of G-CSF after transplant, accelerated neutrophil recovery, and having more than six cycles of previous chemotherapy was an unfavorable factor for recovering >50 x 10(9)/L platelets.

Diagnóstico de enfermedad de Gaucher en una mujer en la 31 semana de gestación / Diagnosis of Gaucher's disease in a woman in week 31 of gestation

No disponible

Gammagrafía con tecnecio-99m-ácido dimercaptosuccínico en el estudio de la primera infección urinaria febril del niño / Technetium-99m-dimercaptosuccinic acid (DMSA) scintigraphy in febrile first-time urinary tract infection in children

Objetivo: Evaluar los hallazgos de la gammagrafía renal (DMSA) en niños con una primera infección del tracto urinario (ITU) febril en relación con diversos parámetros clínico-biológicos y otros estudios de imagen y seguimiento a largo plazo. Material y métodos: En un grupo de 103 pacientes (con edades comprendidas entre un mes y 10 años) con una primera ITU febril, se han evaluado parámetros clínicos, analíticos y pruebas de imagen en la fase aguda de la enfermedad. Los pacientes se dividieron en dos grupos de edad, menores (n = 63) y mayores de 2 años (n = 40). Resultados: La gammagrafía fue patológica en el 54,5 por ciento del grupo total, en el 39,7 por ciento en menores de 2 años y en el 79,5 por ciento de los mayores de 2 años. En la ecografía con medición del volumen renal se detectó una concordancia simple con la gammagrafía en el 64 por ciento de los casos. La cistografía objetivó un reflujo en el 22,3 por ciento de los pacientes, sin encontrar diferencias estadísticamente significativas entre los que presentaron un DMSA normal o patológico. Al estudiar los factores que se asociaron de forma independiente a un resultado patológico en el DMSA mediante un análisis multivariante de regresión logística, se observó que la edad del niño, la elevación de la proteína C reactiva (PCR) y la alteración del volumen renal resultaron asociarse de forma estadísticamente significativa a una mayor presencia de DMSA patológico. Conclusiones: El DMSA combinado con otras pruebas diagnósticas puede mejorar la sensibilidad y especificidad para establecer el grado de afectación renal. Durante el seguimiento, las lesiones agudas desaparecen o mejoran en todos los casos y las crónicas no se modifican (AU)

BMT: Serum Ferritin as Risk Factor for Veno-occlusive Disease of the Liver. Prospective Cohort Study.

Veno-occlusive disease of the liver (VOD) is an important complication in hematological transplantation. The aim of this study is to analyze the risk factors for VOD and other forms of liver toxicity in a cohort of 180 peripheral stem cell transplants performed in our Center. We find that elevated pretransplant levels of serum ferritin are the most important risk marker for VOD. We believe that ferritin reflects damage induced by oxygen radicals resulting from iron-mediated catalysis. We also discuss different risk factors for VOD and other forms of liver toxicity, suggesting diferent pathogenic mechanisms.

Salvage chemotherapy with mini-BEAM for relapsed or refractory Hodgkin's disease prior to autologous peripheral blood stem cell transplantation.

BACKGROUND AND OBJECTIVE: High-dose chemotherapy and autologous bone marrow transplantation (ABMT) has become the standard approach for most patients with relapsed or refractory Hodgkin's disease. Disease status at transplant has been correlated with outcome following ABMT. In light of this, we employ mini-BEAM (BCNU, etoposide, cytarabine and melphalan) salvage therapy in order to achieve a state of minimal residual disease prior to transplantation. DESIGN AND METHODS: From February 1992 to June 1998 twenty-four patients receiving mini-BEAM therapy for resistance or relapse of their Hodgkin's disease were included. Four patients had obtained no response with initial chemotherapy (refractory), eight had obtained an incomplete response, seven were in first relapse and five in second or subsequent relapse. Fifteen patients received mini-BEAM as first salvage chemotherapy regimen. The remaining nine patients had previously been exposed to a median of one salvage regimen. Patients received a median of three cycles of mini-BEAM. RESULTS: Sixteen patients achieved complete remission and four partial remission, yielding an overall response rate of 83%. No significant differences in response were observed between patients who received mini-BEAM as initial salvage therapy and those who had received a prior salvage regimen. Eighteen out of the twenty responding patients went on to intensive therapy and peripheral blood stem cell transplantation. With a median follow-up of 52 months, the cumulative probability of 7-year overall survival is 71% for the responders and that of the 6-year disease-free survival is 42%. No treatment-related deaths were observed. INTERPRETATION AND CONCLUSIONS: Mini-BEAM is an effective salvage regimen with moderate toxicity that may be useful for cytoreduction prior to stem cell procedures.

[The tilt-table test in assessing syncope of unknown origin: do differences exist between children and adults?]. / El test de basculación en la evaluación del síncope de origen desconocido: existen diferencias entre niños y adultos?

BACKGROUND AND OBJECTIVES: Little is known about the differences between children and adults in the results of head-up tilt test. This study sought to investigate the potential differences concerning: a) the clinical profile and circumstances of spontaneous syncope; b) the overall diagnostic performance of the test, and c) the type of positive response obtained. MATERIAL AND METHODS: We studied 31 children and 123 adults with unexplained syncope. If baseline test (tilting at 70 degrees for 30 min) resulted negative, it was repeated under isoprenaline low-dose infusion. RESULTS: There were no differences in either clinical profile, except for severe traumatism more frequent in adults (25% vs. 3% in children; p < 0.05), or overall diagnostic performance (39% in children vs. 33% in adults; p = NS). However, the way the test rendered positive (via basal tilting in 92% of children vs. 50% in adults; p < 0.05) and the rate of cardioinhibitory response (42% in children vs 8% in adults; p < 0.01) were significantly different. CONCLUSIONS: In this study children, in contrast to adults, rarely have a positive response in tilting under isoprenaline infusion. They also present a much higher rate of cardio-inhibitory response than adults.

Serum Ferritin as Risk Factor for Veno-occlusive Disease of the Liver. Prospective Cohort Study.

Veno-occlusive disease of the liver (VOD) is an important complication in hematological transplantation. The aim of this study is to analyze the risk factors for VOD and other forms of liver toxicity in a cohort of 180 peripheral stem cell transplants performed in our Center. We find that elevated pretransplant levels of serum ferritin are the most important risk marker for VOD. We believe that ferritin reflects damage induced by oxygen radicals resulting from iron-mediated catalysis. We also discuss different risk factors for VOD and other forms of liver toxicity, suggesting diferent pathogenic mechanisms.