Structural renal abnormalities in the DICER1 syndrome: a family-based cohort study.

BACKGROUND: The DICER1 syndrome is a tumor-predisposition disorder caused by germline pathogenic variation in DICER1 and is associated with cystic nephroma and other renal neoplasms. Dicer1 mouse and rare human DICER1 syndrome case reports describe structural kidney and collecting system anomalies. We investigated renal function and the frequency of structural abnormalities of the kidney and collecting system in individuals with germline loss-of-function variants in DICER1. METHODS: In this family-based cohort study, prospectively ascertained germline DICER1-mutation carriers (DICER1-carriers) and unaffected family controls were evaluated at the National Institutes of Health Clinical Center with renal ultrasound and comprehensive laboratory testing. Two radiologists reviewed the imaging studies from all participants for structural abnormalities, cysts, and tumors. RESULTS: Eighty-nine DICER1-carriers and 61 family controls were studied. Renal cysts were detected in 1/33 DICER1-carrier children without history of cystic nephroma. Similar proportions of adult DICER1-carriers (8/48; 17%) and controls (11/50; 22%) had ultrasound-detected renal cysts (P = 0.504). 8/89 (9%) DICER1-carriers harbored ultrasound-detected structural abnormalities of varying severity within the collecting system or kidney, nephrolithiasis, or nephrocalcinosis. None of the family controls (0/61) had similar findings on ultrasound (P = 0.02). No meaningful differences in renal laboratory values between DICER1-carriers and unaffected family controls were observed. CONCLUSIONS: Our report is the first to systematically characterize renal function and anatomy in a large prospective cohort of DICER1-carriers and DICER1-negative family controls. DICER1-carriers may be at increased risk of structural anomalies of the kidney or collecting system. The role for DICER1 in renal morphogenesis merits additional investigation.

Caliceal diverticulum in pediatric patients: the spectrum of imaging findings.

BACKGROUND: Caliceal diverticulum (CD) is uncommon in children. As compared to adults, most children with CD are symptomatic. Common complications include stone formation and infection. Correct diagnosis of CD is important for guiding management. OBJECTIVE: To identify imaging findings at diagnosis and follow-up in pediatric patients with CD. MATERIALS AND METHODS: We identified all patients from 2003 to 2010 with a diagnosis of CD. We reviewed presenting symptoms, underlying diseases, complications, management, and all pertinent radiological examinations. RESULTS: Twenty-four patients (2.6 to 18.5 years old, 11 females) had CD. Urinary tract infection was the most common (n = 8) presentation. Diagnosis of CD was based on delayed post-contrast CT in 79% of patients with only one false-negative CT. Most patients (n = 20) had a single CD; others had either 2 CDs (n = 2) or multiple CDs (n = 2). CD diameter ranged from 1.0 to 18.3 cm and grew in five of nine patients who had follow-up studies. Seven patients developed stone in the CD. Fifteen patients (63%) underwent a surgical procedure. CONCLUSIONS: CD is commonly solitary, often grows with time and may mimic other diagnoses, including simple cyst, complex cyst and polycystic kidney disease. Delayed postcontrast CT is highly sensitive in diagnosing CD.

ACR Appropriateness Criteria Fever Without Source or Unknown Origin-Child.

The cause of fever in a child can often be determined from history, physical examination, and laboratory tests; infections account for the majority of cases. Yet in 20%, no apparent cause can be found, designated as fever without source (FWS). The yield of chest radiography in children with FWS is low, and it is usually not appropriate. However, in children with respiratory signs, high fever (>39°C), or marked leukocytosis (≥20,000/mm(3)), chest radiography is usually appropriate, as it has a higher yield in detecting clinically occult pneumonia. In newborns with FWS, there is higher risk for serious bacterial infection, and the routine use of chest radiography is controversial. In children with neutropenia, fever is a major concern. In some clinical circumstances, such as after hematopoietic stem cell transplantation, chest CT scan may be appropriate even if the results of chest radiography are negative or nonspecific, as it has higher sensitivity and can demonstrate specific findings (such as lung nodule and "halo sign") that can guide management. In a child with prolonged fever of unknown origin despite extensive medical workup (fever of unknown origin), diagnosis is usually dependent on clinical and laboratory studies, and imaging tests have low yield. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria Vomiting in Infants up to 3 Months of Age.

Vomiting is a commonly reported symptom in infants less than three months of age. There are a multitude of pathologies to consider, both within and outside the gastrointestinal tract. In addition to conducting a thorough history and physical examination, a clinician formulates a reasonable differential diagnosis by consideration of two main factors: the infant's age and the characterization of the vomit as bilious or nonbilious. In this endeavor, the clinician is able to determine if an imaging study is needed and, if so, the urgency of the request. A review of the appropriate imaging evaluation of vomiting infants in the newborn to three-month-old age group is provided by organizing the discussion around the following three clinical scenarios: bilious vomiting, intermittent nonbilious vomiting since birth, and new-onset bilious vomiting. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every three years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

ACR Appropriateness Criteria head trauma--child.

Head trauma is a frequent indication for cranial imaging in children. CT is considered the first line of study for suspected intracranial injury because of its wide availability and rapid detection of acute hemorrhage. However, the majority of childhood head injuries occur without neurologic complications, and particular consideration should be given to the greater risks of ionizing radiation in young patients in the decision to use CT for those with mild head trauma. MRI can detect traumatic complications without radiation, but often requires sedation in children, owing to the examination length and motion sensitivity, which limits rapid assessment and exposes the patient to potential anesthesia risks. MRI may be helpful in patients with suspected nonaccidental trauma, with which axonal shear injury and ischemia are more common and documentation is critical, as well as in those whose clinical status is discordant with CT findings. Advanced techniques, such as diffusion tensor imaging, may identify changes occult by standard imaging, but data are currently insufficient to support routine clinical use. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 3 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

ACR Appropriateness Criteria® limping child--ages 0 to 5 years.

The appropriate imaging for pediatric patients (ages 0-5 years) being evaluated for limping depends on the clinical presentation, specifically, the presence of signs of infection, any localization of pain, and history of or suspected trauma. Common diagnoses causing limping in children are briefly reviewed, and recommended imaging techniques are discussed, including toddler's fracture, transient synovitis, septic arthritis, Legg-Calvé-Perthes disease, and osteomyelitis. The ACR Appropriateness Criteria(®) are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Labyrinthine dehiscence in a child.

A 4-year-old boy presented with moderate to profound mixed hearing loss in the right ear and moderate to severe mixed hearing loss in the left ear, prompting a temporal bone CT scan. Images revealed partial dehiscence of the right posterior semicircular canal. Semicircular canal dehiscence and its associated clinical syndrome have been described in adults. We present this case as a unique finding in a child and discuss the possible clinical and research implications.