Development and Validation of a Pediatric MRI-Based Perianal Crohn Disease (PEMPAC) Index-A Report from the ImageKids Study.

BACKGROUND: As part of the prospective multicenter ImageKids study, we aimed to develop and validate the pediatric MRI-based perianal Crohn disease (PEMPAC) index. METHODS: Children with Crohn disease with any clinical perianal findings underwent pelvic magnetic resonance imaging at 21 sites globally. The site radiologist and 2 central radiologists provided a radiologist global assessment (RGA) on a 100 mm visual analog scale and scored the items selected by a Delphi group of 35 international radiologists and a review of the literature. Two weighted multivariable statistical models were constructed against the RGA. RESULTS: Eighty children underwent 95 pelvic magnetic resonance imaging scans; 64 were used for derivation and 31 for validation. The following items were included: fistula number, location, length and T2 hyperintensity; abscesses; rectal wall involvement; and fistula branching. The last 2 items had negative beta scores and thus were excluded in a contending basic model. In the validation cohort, the full and the basic models had the same strong correlation with the RGA (r = 0.75; P < 0.01) and with the adult Van Assche index (VAI; r = 0.93 and 0.92; P < 0.001). The correlation of the VAI with the RGA was similar (r = 0.77; P < 0.01). The 2 models and the VAI had a similar ability to differentiate remission from active disease (area under the receiver operating characteristic curve, 0.91-0.94). The PEMPAC index had good responsiveness to change (area under the receiver operating characteristic curve, 0.89; 95% confidence interval, 0.69-1.00). CONCLUSIONS: Using a blended judgmental and mathematical approach, we developed and validated an index for quantifying the severity of perianal disease in children with CD. The adult VAI may also be used with confidence in children.

A Distinct Metabolite Profile Correlates with Neurodegenerative Conditions and the Severity of Congenital Hydrocephalus.

In congenital hydrocephalus, cerebrospinal fluid accumulation is associated with increased intracranial pressure (ICP), ischemia/hypoxia, metabolic impairment, neuronal damage, and astrocytic reaction. The aim of this study was to identify whether a metabolite profile revealing tissue responses according to the severity of hydrocephalus can be detected. The hyh mutant mouse used for this study exhibits 2 different forms of hydrocephalus, severe and moderate. In a comprehensive investigation into the 2 progressions of hydrocephalus, mice with severe hydrocephalus were found to have higher ICP and astrocytic reaction. Several metabolites from the mouse brain cortex were analyzed with 1H high-resolution magic angle spinning nuclear magnetic resonance (1H HR-MAS NMR) spectroscopy. A differential profile for metabolites including glutamate and glutamine was found to correlate with the severity of hydrocephalus and can be explained due to differential astrocytic reactions, neurodegenerative conditions, and the presence of ischemia. The glutamate transporter EAAT2 and the metabolite taurine were found to be key histopathological markers of affected parenchymata. In conclusion, a differential metabolite profile can be detected according to the severity of hydrocephalus and associated ICP and therefore can be used to monitor the efficacy of experimental therapies.

Presentación de un caso de hemicerebelitis pediátrica / Pediatric hemicerebellitis: a case report

La cerebelitis aguda es una de las causas principales de disfución cerebelar aguda en pediatría; puede ser infecciosa, postinfecciosa o posvacunal, y generalmente es de etiología viral. El diagnóstico es difícil porque la clínica presenta sólo algunos de los signos de patología cerebelosa y el líquido cefalorraquídeo puede ser normal. La afectación de un único hemisferio cerebeloso, hemicerebelitis, es muy infrecuente, hay publicados tres casos hasta el año 2003. La resonancia magnética muestra edema cerebeloso unilateral con realce que sigue la morfología de las folias; este patrón es de gran ayuda para el diagnóstico. Aunque es una entidad que se considera benigna, autolimitada y con buena evolución con tratamiento corticoide, a veces es necesaria la biopsia para diferenciarla de patología tumoral

Acute cerebellitis is one of the main causes of acute cerebellar dysfunction in pediatrics. It can be infectious or occur after infection or vaccination; it is usually viral in origin. It is difficult to diagnose because not all of the clinical signs of cerebellar pathology are present and CSF may be normal. Involvement of a single hemisphere of the cerebellum, hemicerebellitis, is very rare: only three cases were published before 2003 (en castellano dice: hasta 2003; si el año 2003 queda incluso, tiene que ser before 2004). MRI shows unilateral cerebellar edema and enhancement along the folia. This pattern is very helpful in the diagnosis. Although this entity is considered to be a benign, self-limiting disorder that responds well to corticosteroid treatment, it is sometimes necessary to differentiate it from tumors

Induction of apoptosis and effect on CD20+ using rituximab on autologous peripheral blood stem cell harvests from patients with B cell lymphomas.

Purging of neoplastic cells for autologous stem cell transplantation is usually done in vivo by administering chemotherapy and/or other agents before harvesting. It is also possible to decrease malignant cells counts directly in the cell harvest. In this study, we ascertained the effect of anti-CD20 monoclonal antibody and rituximab administration on peripheral blood hematopoietic stem cells. Five samples of stem cell harvests from different patients with B cell lymphoma were obtained. Each sample was divided in two tubes with calcium gluconate (20 mEq/50 microl). Rituximab (1 mg/600,000 mononuclear cells) was added to one of the tubes. Using flow cytometry, CD19, CD20 (B cell markers), and CD95 (apoptosis marker), expression was measured at baseline and 24 h after the addition of rituximab. A one-sided t-test with equal variances was used to analyze the results. Immediately after rituximab addition, CD20 expression became null. No significant difference in variation of CD19 expression was detected after the addition of rituximab (-3.64% control vs. 0.63% rituximab, p = 0.69). Mean variations of percentage of CD95 expression were 2.9% (controls) and 10.52% (rituximab tubes) (p = 0.06). We conclude that rituximab is capable of initiating apoptosis in vitro. We found no decrease in the CD19+ cell count, used as a surrogate marker for CD20+ cells, meaning that, at least in 24 h, apoptosis activation is not capable of decreasing CD20+ cell numbers. In vitro purging of peripheral blood stem cells harvests with rituximab could be part of a broader therapeutic strategy to be offered to lymphoproliferative disorder patients.

Estudio por imagen del desarrollo de tumores linforreticulares en la ataxia telangiectasia y el síndrome de Nijmegen / Imaging study of lymphoreticular tumor development in ataxia-telangiectasia and Nijmegen breakage syndrome

La ataxia telangiectasia de Louis Barr (AT) es una enfermedad autosómica recesiva caracterizada por ataxia cerebelosa progresiva, telangiectasias oculocutáneas, inmunodeficiencia combinada con susceptibilidad a infecciones sinopulmonares y alta incidencia de desarrollo neoplásico. El síndrome de Nijmegen (SNJ) es una variante de la AT, también autosómico recesivo, que presenta ataxia cerebelosa, inmunodeficiencia combinada y tendencia al desarrollo tumoral. A diferencia de la AT no muestra telangiectasias y exhibe un fenotipo característico (talla corta, cara «de pájaro» y microcefalia). Ambas entidades se incluyen dentro de la clasificación de los síndromes con fragilidad o inestabilidad cromosómica que agrupan además al síndrome de Bloom y la anemia de Fanconi. Todos ellos muestran un aumento en la frecuencia de presentación neoplásica, principalmente tumores del sistema linfoide. Presentamos tres pacientes, dos con AT y uno con SNJ, que han desarrollado diferentes tipos de linfoma en el curso de la enfermedad, indicando los aspectos más relevantes desde el punto de vista clinicorradiológico (AU)

Ataxia-telangiectasia (AT), or Louis-Bar syndrome, is an autosomal recessive illness characterized by progressive cerebellar ataxia, oculocutaneous telangiectasias, immunodeficiency combined with susceptibility to sinopulmonary infections and high incidence of neoplastic development. Nijmegen breakage syndrome (NBS) is a variant of AT, is also an autosomal recessive illness that presents cerebellar ataxia, as well as combined immunodeficiency and a tendency toward tumor development. Contrary to Louis-Bar syndrome, it doesn't present telangiectasia and exhibits a characteristic phenotype (short stature, bird-like face and microcephaly). Both entities are classified as syndromes of chromosomal instability or chromosomal fragility, a group which also includes Bloom syndrome and Fanconi anemia. All of these show an increase in the frequency of neoplastic pathologies, mainly lymphoid tumors. We present three patients, two with AT and one with NBS, who developed different lymphoma types in the course of the illness. We highlight the most outstanding aspects from a clinical-radiological point of view (AU)

El síndrome del hueso evanescente / Vanishing bone disease

El Síndrome de Gorham o hueso evanescente u osteolisis masiva es una patología rara con etiología y patogenia aún desconocidas. Acontece una reabsorción ósea progresiva y espontánea de uno o varios huesos contiguos alrededor de un foco, sin respetar los límites articulares. Puede afectar a cualquier parte del esqueleto, pero se ha descrito con mayor frecuencia en articulaciones del hombro y la pelvis. No se asocia historia familiar y la edad de presentación suele ser en adolescentes y adultos jóvenes. La regeneración del hueso no se produce aunque cese la progresión osteolítica. No se han descrito focos múltiples simultáneos no contiguos ni metástasis a distancia. La patología se considera benigna y la lisis ósea suele cesar tras unos años. El diagnóstico es de exclusión basándose en la evolución clínico-radiológica y en los hallazgos histológicos compatibles. Describimos un nuevo caso con los hallazgos clínicos, radiológicos e histopatológicos característicos del síndrome (AU)