[Nephroblastomatosis vs Wilms' tumor: a case report]. / Nefroblastomatosis frente a tumor de Wilms: a propósito de un caso.

Nephroblastomatosis is an abnormality of nephrogenesis and has been defined as the persistence of metanephric blastema into infancy. The association of these foci of fetal tissue with Wilms' tumor has been repeatedly documented in the literature. Numerous imaging modalities currently enable the detection of nephroblastomatosis and follow-up of patients to detect neoplastic change, which is especially indicated during infancy and early childhood, when the likelihood of Wilms' tumor developing is highest.

Nefroblastomatosis frente a tumor de Wilms: a propósito de un caso / Nephroblastomatosis vs Wilms' tumor: a case report

La nefroblastomatosis es una alteración de la nefrogénesis que se define como la persistencia de blastema metanéfrico en la infancia. La asociación de estos focos de tejido fetal con el tumor de Wilms se encuentra ampliamente documentada en la literatura. En la actualidad disponemos de numerosas técnicas de imagen que van a permitir el diagnóstico y seguimiento de esta entidad, especialmente en los primeros años de vida, cuando el riesgo de malignización es mayor (AU)

Nephroblastomatosis is an abnormality of nephrogenesis and has been defined as the persistence of metanephric blastema into infancy. The association of these foci of fetal tissue with Wilms' tumor has been repeatedly documented in the literature. Numerous imaging modalities currently enable the detection of nephroblastomatosis and follow-up of patients to detect neoplastic change, which is especially indicated during infancy and early childhood, when the likelihood of Wilms' tumor developing is highest (AU)

[Biological cost associated with fosfomycin resistance in Escherichia coli isolates from urinary tract infections]. / Coste biológico asociado a la resistencia a la fosfomicina en aislamientos de Escherichia coli de orina.

Resistance to fosfomycin develops rapidly in experimental conditions, although despite its frequent use in UTI, resistance in E. coli, the main uropathogen, is very low (1-3%), and has remained so for many years. The objective of this study was to ascertain whether E. coli fosfomycin-resistant strains have less fitness than those that are fosfomycin-sensitive in competing, and would therefore tend to disappear in their competition with fosfomycin-sensitive strains in the absence of antibiotics. Fosfomycin-resistant strains (n=11) with different phenotypes of resistance to other antibiotics were used. All but one were lactose (+). Fosfomycin-susceptible strains (n=15) that had the same phenotypes of resistance to other antibiotics as the resistant strains and which had the opposite pattern of lactose fermentation were also used. Thirty-three (33) competition experiments by pairs of strains were conducted in nutrient broth. Equal amounts of the strains were challenged (approx. 50% and approx. 50%) for 4 days, with a daily change to a new medium. Five differential counts were performed on days 0, 1, 2, 3 and 4. In 20 experiments (60.6%) there was a relative increase in the fosfomycin-sensitive strain. In 6 experiments (18.2%) there was a relative increase in the fosfomycin-resistant strain. In 7 experiments (21.2%), on the fourth day none of the strains reached 60%. When the data of the 26 (20+6) experiments in which there were changes were analyzed by the chi2 test there was a statistically significant difference (p=0.044). Resistance to fosfomycin could entail a biological cost (less fitness) for the majority of the E. coli strains assayed.

Coste biológico asociado a la resistencia a la fosfomicina en aislamientos de Escherichia coli de orina / Biological cost associated with fosfomycin resistance in Escherichia coli isolates from urinary tract infections

La resistencia a la fosfomicina surge rápidamente en condiciones experimentales, pero aunque su uso es frecuente en las infecciones del tracto urinario, la resistencia de Escherichia coli, el principal uropatógeno, es muy baja (1% a 3%) y ha permanecido así por muchos años. El objetivo de este estudio fue evaluar si las cepas de E. coli resistentes a la fosfomicina tienen menos competitividad (fitness) que las sensibles, y por tanto tenderían a desaparecer al competir con las cepas sensibles en ausencia de antibióticos. Se utilizaron cepas resistentes a la fosfomicina (n=11) con diferentes fenotipos de resistencia a otros antibióticos, y cepas sensibles a la fosfomicina (n=15) con los mismos fenotipos de resistencia al resto de los antibióticos que algunas de las cepas resistentes, pero con el patrón opuesto de fermentación de la lactosa. Se realizaron 33 experimentos de competición por pares en caldo nutriente. Se utilizaron cantidades iguales de cada cepa (50%-50%) durante cuatro días, con cambio diario a un nuevo medio. Se hicieron cinco recuentos diferenciales, los días 0, 1, 2, 3 y 4. En 20 experimentos (60,6%) hubo un incremento relativo de la cepa sensible a la fosfomicina. En seis experimentos (18,2%) hubo un incremento relativo de la cepa resistente a la fosfomicina. En siete experimentos (21,2%) ninguna cepa mostró un incremento relativo. Cuando los datos de los 26 experimentos en que había cambios se analizaban por X2 había una diferencia estadísticamente significativa (p=0.044). La resistencia a la fosfomicina puede suponer un coste de competitividad para la mayoría de las cepas de E. coli probadas

Resistance to fosfomycin develops rapidly in experimental conditions, although despite its frequent use in UTI, resistance in E. coli, the main uropathogen, is very low (1-3%), and has remained so for many years. The objective of this study was to ascertain whether E. coli fosfomycin- resistant strains have less fitness than those that are fosfomycin-sensitive in competing, and would therefore tend to disappear in their competition with fosfomycin-sensitive strains in the absence of antibiotics. Fosfomycin-resistant strains (n=11) with different phenotypes of resistance to other antibiotics were used. All but one were lactose (+). Fosfomycin-susceptible strains (n=15) that had the same phenotypes of resistance to other antibiotics as the resistant strains and which had the opposite pattern of lactose fermentation were also used. Thirty-three (33) competition experiments by pairs of strains were conducted in nutrient broth. Equal amounts of the strains were challenged (approx. 50% and approx. 50%) for 4 days, with a daily change to a new medium. Five differential counts were performed on days 0, 1, 2, 3 and 4. In 20 experiments (60.6%) there was a relative increase in the fosfomycin-sensitive strain. In 6 experiments (18.2%) there was a relative increase in the fosfomycin-resistant strain. In 7 experiments (21.2%), on the fourth day none of the strains reached 60%. When the data of the 26 (20+6) experiments in which there were changes were analyzed by the X2 test there was a statistically significant difference (p=0.044). Resistance to fosfomycin could entail a biological cost (less fitness) for the majority of the E. coli strains assayed

Seguimiento radiológico / No disponible

No disponible

Low-dose high-resolution CT of the chest in children and young adults: dose, cooperation, artifact incidence, and image quality.

OBJECTIVE: The radiation dose, artifact incidence, and image quality of high-resolution chest CT examinations performed with standard and low doses and patient cooperation were investigated in children and young adults. SUBJECTS AND METHODS: Three successive controlled studies were conducted in different groups of children and young adults, totaling 203 patients. Dosimetry of high-resolution CT was performed at 180, 50, and 34 mAs in three groups of 25 patients. Streak artifact incidence using alternating 50- and 34-mAs slices was assessed and correlated with patient compliance with breath-holding commands in 44 children. Image quality was evaluated in scans obtained with 34 versus 180 mAs in cooperative patients (n = 42) and in scans obtained with 50 versus 180 mAs in noncooperative patients (n = 42). Artifacts and image quality were assessed by controlled repeated interpretations. RESULTS: Radiation dose was 5.4+/-1.6 mSv for 180 mAs, 1.5+/-0.5 mSv for 50 mAs, and 1.1+/-0.3 mSv for 34 mAs. Cooperation was obtained in 66% of the patients. Artifacts were more frequently seen in scans of noncooperative patients (30%) and in 34-mAs scans (47%); the highest incidence was found using 34 mAs in noncooperative patients (60%, p = 0.02). No differences in image quality scores were seen in scans obtained with 50 mAs versus those obtained with 180 mAs in noncooperative patients (p<0.05), and small differences were found in scans obtained with 34 mAs versus those obtained with 180 mAs in cooperative patients for fissures (p = 0.005) and peripheral structures (p = 0.02). CONCLUSION: Low-dose high-resolution CT provided a significant reduction in radiation dose (72% for 50 mAs and 80% for 34 mAs) and good-quality images of the lung when performed with 50 mAs in noncooperative and 34 mAs in cooperative pediatric and young adult patients.

Cervicothoracic lesions in infants and children.

Cervicothoracic lesions are not uncommon in children. All cervicothoracic lesions except superficial lesions extend from the neck to the thorax through the thoracic inlet. Evaluation of this area involves multiple imaging modalities: plain radiography, ultrasonography, nuclear medicine, computed tomography, and magnetic resonance (MR) imaging. However, MR imaging is the method of choice for assessing the full extents of cervicothoracic lesions and their relationships to neurovascular structures. Cervicothoracic lesions can be classified as congenital lesions, inflammatory lesions, benign tumors, malignant tumors, and traumatic lesions. Lymphangioma is the most common cervicothoracic mass in children; other congenital lesions include hemangioma, thymic cyst, and vascular anomalies. Inflammatory adenopathy reactive to tuberculosis, mononucleosis, tularemia, cat-scratch fever, infection with human immunodeficiency virus, or other upper respiratory tract infections can manifest as cervicothoracic lesions; tuberculous abscesses and abscesses of other origins can also be seen. Lipoma, lipoblastoma, aggressive fibromatosis, and nerve sheath tumors (either isolated lesions or those associated with neurofibromatosis) can also occur as cervicothoracic masses. Malignant cervicothoracic tumors include lymphoma, thyroid carcinoma, neuroblastoma, and chest wall tumors (rhabdomyosarcoma, Ewing sarcoma, and neuroectodermal tumor). Traumatic cervicothoracic lesions include pneumomediastinum of traumatic origin, traumatic pharyngeal pseudodiverticulum, esophageal foreign-body granuloma, and cervicothoracic hematoma.

Pediatric pancreas: an overview.

Pancreatic disorders are not rare in children. Modern imaging equipment allows recognition of many pancreatic diseases that were difficult to identify in the past and therefore were considered to be unusual. Within the scope of this article we include information on imaging modalities for studying the pancreas and a description of the radiologic manifestations of the most common congenital, inflammatory, tumoral, traumatic and systemic disorders.

Spectrum of manifestations of Swyer-James-MacLeod syndrome.

PURPOSE: The clinical and imaging findings of children with Swyer-James-MacLeod syndrome (SJMS) were reviewed to determine the incidence and type of bronchiectasis and analyze whether the clinical course of patients with bronchiectasis differed from that of patients without bronchiectasis. METHOD: Our study population consisted of 13 patients. All had inspiratory/ expiratory chest X-ray films, chest CT, and lung scans. Eight underwent pulmonary function test. The results of these studies at diagnosis and during follow-up were analyzed and compared with the clinical features. RESULTS: Bronchiectasis was demonstrated in nine patients, being saccular in five and cylindrical in four. Expiratory slices were helpful for demonstrating bilateral lung involvement that had not been suspected on inspiratory CT scans or conventional radiographs. The clinical features of the five patients with saccular bronchiectasis resembled those of patients with classic postviral bronchiectasis who suffered recurrent pulmonary infections; three of them underwent lobectomy. The remaining patients presented mild respiratory symptoms, with a spontaneous tendency toward improvement. CONCLUSION: SJMS should be considered as a spectrum disease. Bronchiectasis is not a universal finding. The presence and type of bronchiectasis will influence clinical manifestations and prognosis. Patients without bronchiectasis or with cylindrical bronchiectasis had a lower incidence of pneumonia episodes than those with saccular bronchiectasis.

Spontaneous involution of pulmonary sequestration in children: a report of two cases and review of the literature.

BACKGROUND: Two cases of pulmonary sequestration which regressed spontaneously are presented. OBJECTIVE: To demonstrate the value of imaging studies in the diagnosis and follow-up of some forms of congenital masses of the lung in asymptomatic patients. MATERIAL AND METHODS: We reviewed the clinical records and imaging studies of two asymptomatic children, one newborn and the other 3 months old, with thoracic masses which demonstrated variable degrees of spontaneous involution. RESULTS: Abdominal ultrasound performed on the newborn with a palpable mass showed a triangular echogenic mass with a large central feeding vessel arising from the aorta. The mass had disappeared on follow-up US exam performed 6 years later. CT was performed in the 3-month-old patient with a persistent retrocardiac mass. A soft-tissue density mass in the left pulmonary base with a large feeding vessel arising from the aorta was visualised on contrast-enhanced CT. Five years later, a new CT scan showed significant shrinkage of the mass and no vessel. CONCLUSION: Radiological techniques such as real-time US with Doppler imaging and contrast-enhanced CT may establish the diagnosis of pulmonary sequestration by demonstrating the mass and its systemic vessel, thereby eliminating the need for more aggressive imaging procedures. Partial or total disappearance of these masses represents a further example of involutive pathology and suggests that not all cases of pulmonary sequestration should be surgically treated.

Renal calcifications in patients with autosomal recessive polycystic kidney disease: prevalence and cause.

OBJECTIVE: We investigated the prevalence of renal calcifications in children with autosomal recessive polycystic kidney disease and studied the metabolic changes that could cause this complication. SUBJECTS AND METHODS: Nine patients with known autosomal recessive polycystic kidney disease were examined with sonography and CT and screened for biochemical evidence of metabolic causes of nephrocalcinosis. RESULTS: CT showed bilateral renal calcifications in seven of the nine patients. The two patients without renal calcifications were less than 1 year old. Four patients had only a few calcifications and three patients had many. The severity of the renal calcifications correlated with the degree of kidney failure. All patients with kidney failure were found to have urine acidification defects. Hypocitraturia was present in all patients. CONCLUSION: Our results show that renal calcifications are common in older children with autosomal recessive polycystic kidney disease. Hypocitraturia and the urine acidification defect resulting from kidney failure are the leading factors in the pathogenesis of the calcifications.

Intrahepatic biliary stones in children.

Intrahepatic biliary stones in seven non-Oriental patients were studied in all by sonography, in four patients by computed tomography and in four patients by percutaneous transhepatic cholangiography. For patients had extrahepatic biliary atresia treated with portoenterostomies, one patient had undergone partial liver transplantation and of the remaining two, one had cystic fibrosis and the other immunodeficiency syndrome. All sonograms were abnormal and showed echogenic foci within the liver, with or without associated signs of biliary tract dilatation. CT confirmed the biliary tract dilatation yet calculi were identified in one patient only. PTC was particularly helpful in the patient with immunodeficiency in whom features typical of sclerosing cholangitis were found. This report emphasizes the variable radiological appearance of bile stones which to our knowledge have rarely been described in children with entities other than Oriental cholangitis.

Juvenile xanthogranuloma with extracutaneous lesions.

The purpose of this article is to present a case of juvenile xanthogranuloma with pulmonary, retroperitoneal and splenic involvement. The similar echographic pattern of the cutaneous and visceral lesions was very helpful in order to suggest the correct diagnosis.

Osteofibrous dysplasia. A report of two cases.

Two cases of osteofibrous dysplasia of long bones are reported, one in a neonate with ipsilateral tibial and fibular involvement and the other in a 6-year-old patient with bilateral tibial lesions. The radiological features of the younger patient were remarkably different from those of the older one. These two different and age-related radiological patterns have also been found in most cases previously reported. All the lesions tended to regress spontaneously.