Bile Ducts in Regenerative Liver Nodules of Alagille Patients Are Not the Result of Genetic Mosaicism.

Alagille syndrome (ALGS) is a complex, multisystem disease associated with mutations in the JAG1 gene. In the liver, ALGS is characterized by paucity of intrahepatic bile ducts. Gene dosage analysis performed on a large, central regenerative nodule with preserved interlobular bile ducts of 2 unrelated ALGS patients, and on surrounding cirrhotic and ductopenic liver parenchyma, showed in both cases complete JAG1 heterozygous deletion in the regenerative nodule and the ductopenic liver, with no differences in gene dosage. Thus, JAG1 mosaicism and differential haploinsufficiency do not explain the presence of bile ducts in centrally located regenerative nodules.

Evaluation of bedside sonography performed by emergency physicians to detect intussusception in children in the emergency department.

OBJECTIVE: The aim of our study was to evaluate the test characteristics of point-of-care ultrasound (POCUS) performed by emergency physicians with varying levels of experience among children having undergone diagnostic radiology ultrasound for intussusception in a pediatric emergency department (PED). METHODS: This was a subanalysis of a prospective cohort study conducted at a tertiary care PED. The study population was a sample of children younger than 5 years old who required an abdominal ultrasound for suspected intussusception. Participating physicians had varying levels of POCUS experience. They received a 1-hour didactic and practical training session on intussusception ultrasound. All POCUS was performed following the initial physical examination and prior to further radiologic evaluation. The final outcome was determined by radiologic evaluation performed by a pediatric radiologist. Test characteristics were calculated for POCUS compared with the criterion standard of ultrasound read by a pediatric radiologist. A secondary analysis compared test characteristics of POCUS performed by physicians with different level of POCUS training. RESULTS: A total of 131 children were evaluated by POCUS, of whom 45 (34%) had an intussusception. Twenty-four physicians performed between one and 25 POCUS procedures. POCUS identified 39 of 45 intussusception cases, with a sensitivity of 0.87 (95% confidence interval [CI] = 0.74 to 0.94). A normal or inconclusive POCUS was reported for 83 of the 86 negative studies, with a specificity of 0.97 (95% CI = 0.90 to 0.99). When excluding the 28 patients for whom the physician reported an inconclusive examination, the sensitivity improved to 0.98 (95% CI = 0.97 to 1.00) and the specificity to 0.94 (95% CI = 0.85 to 0.99). The accuracy of diagnosis using POCUS was 42 of 43 (98%) for experienced sonographers in comparison to 81 of 88 (92%) for novices. CONCLUSION: This study demonstrated a very good sensitivity and specificity of POCUS for intussusception in children when performed by multiple emergency physicians with varying POCUS experience.

Natural History of Benign Nonimmediate Allergy to Beta-Lactams in Children: A Prospective Study in Retreated Patients After a Positive and a Negative Provocation Test.

BACKGROUND: The drug provocation test (DPT) is considered as the gold standard to diagnose drug allergy and is particularly important in the diagnosis of nonimmediate beta-lactam (BL) allergy in children. The natural history of BL allergy remains unknown. OBJECTIVE: Our main aim was to evaluate the natural history of nonimmediate BL hypersensitivity and the long-term tolerance acquisition, and our secondary objective was to determine the negative predictive value (NPV) of the DPT following a 2-day protocol. METHODS: Children developing a benign rash while treated by BL were prospectively recruited at the Emergency Department of the Geneva University Hospital from 2006 to 2011 and challenged with the incriminated BL (initial diagnostic drug provocation test [idDPT]) following a 2-day protocol. In case of a positive idDPT, the patients underwent a follow-up drug provocation test (fuDPT) 3 years later. In case of a negative idDPT, we sent a questionnaire to assess tolerance of a subsequent treatment with the incriminated BL. RESULTS: Among the 18 children with a positive idDPT, 16 children (89%) had a negative fuDPT and 2 children developed a benign exanthema. Among those 16 children, 11 tolerated a subsequent treatment with the incriminated BL without any reaction, suggesting natural antibiotic tolerance acquisition. From another point of view, we found that the NPV of the DPT following a 2-day protocol was excellent at 96.7%. CONCLUSIONS: Our data strongly suggest that a fuDPT is safe and useful to assess tolerance acquisition in children with a confirmed benign nonimmediate BL allergy. In addition, our results support the use of a short DPT protocol (2 days), which led to a high NPV of 96.7% in our population, with a favorable benefit-risk balance.

Chest CT in bronchopulmonary dysplasia: clinical and radiological correlations.

BACKGROUND: Chest CT is very sensitive in assessing pulmonary damage in bronchopulmonary dysplasia (BPD) and radiological findings in BPD are well described. Validated CT scores are available to assess BPD, as available in other pulmonary diseases such as cystic fibrosis. AIM: To investigate whether there is a correlation between radiological pulmonary lesions and relevant BPD clinical data (gestational age, type and duration of mechanical ventilation, and severity of BPD) and assess the usefulness of a CT score in evaluating clinical severity. MATERIALS AND METHODS: Retrospective study of 19 premature infants with BPD born between 1998 and 2007 who underwent at least one chest CT during their first year of life. A total of 29 CT were blindly evaluated by two radiologists for the presence or absence of pulmonary parenchymal abnormalities described in BPD (areas of decreased attenuation, presence of bullae/emphysema, bronchial wall thickening, bronchiectasis, linear, and subpleural opacities). This score was then compared with the most relevant clinical data. RESULTS: All CT scans showed abnormalities. The most frequent lesion was bronchial wall thickening observed in all patients, followed by linear (89.5%) and subpleural (89.5%) opacities. Areas of decreased attenuation were found in 68.4%. Bullae/emphysema and bronchiectasis were the less frequent item described (26.3% and 21.1%, respectively). The presence of areas of decreased attenuation significantly correlated with BPD severity (P = 0.03). However, there was no significant correlation between the CT score and clinical data. CONCLUSIONS: This study demonstrates the potential usefulness of chest CT score to assess the severity of BPD. Areas of decreased attenuation seem the most sensitive item to predict BPD severity. More patients are needed to validate this approach and to evaluate the long-term usefulness of CT scan.