Validation of the Radiographic Global Impression of Change (RGI-C) score to assess healing of rickets in pediatric X-linked hypophosphatemia (XLH).

BACKGROUND: Rickets is a primary manifestation of pediatric X-linked hypophosphatemia (XLH) - a rare progressive hereditary phosphate-wasting disease. Severity is quantified from radiographs using the Rickets Severity Scale (RSS). The Radiographic Global Impression of Change (RGI-C) is a complementary assessment in which a change score is assigned based on differences in the appearance of rickets on pairs of radiographs compared side by side. OBJECTIVE: The current study evaluated the reliability, validity, and sensitivity to change of the RGI-C specifically in pediatric XLH. METHODS: The reliability, validity, and sensitivity to change of the RGI-C were evaluated using data from two studies in pediatric XLH (113 children aged 1-12 years) in which burosumab treatment significantly improved rickets severity. Intra-rater and inter-rater reliability were assessed by three pediatric radiologists. RESULTS: Intra-rater reliability for RGI-C global score was >90% for agreement within 1 point, with weighted kappa values >0.5, indicating moderate to almost perfect agreement. Inter-rater reliability was also >90% (0.47-0.52 for all reader pairs; moderate agreement). The RGI-C global score showed significant relationships with changes from baseline to week 64 in serum phosphorus (r = -0.397), alkaline phosphatase (-0.611), total RSS (-0.672), standing height (0.268), and patient-reported global functioning (0.306) and comfort/pain functioning (0.409). Based on standardized response means, RGI-C global scores were sensitive to change in RSS, differentiating between those considered improved and greatly improved. Results for validity and sensitivity to change were similar for the RGI-C wrist, knee, and standing long leg scores. CONCLUSION: The RGI-C is a reliable, valid, and sensitive measure in pediatric XLH, and complementary to the RSS.

Pediatric nonaccidental abdominal trauma: what the radiologist should know.

Abdominal injury in nonaccidental trauma (NAT) is an increasingly recognized cause of hospitalization in abused children. Abdominal injuries in NAT are often severe and have high rates of surgical intervention. Certain imaging findings in the pediatric abdomen, notably bowel perforation and pancreatic injury, should alert the radiologist to possible abuse and incite close interrogation concerning the reported mechanism of injury. Close inspection of the imaging study is warranted to detect additional injury sites because these injuries rarely occur in isolation. When abdominal injury is suspected in known or speculated NAT, computed tomography (CT) of the abdomen and pelvis with intravenous contrast material is recommended for diagnostic and forensic evaluation. Although the rate of bowel injury is disproportionately high in NAT, solid organs, including the liver, pancreas, and spleen, are most often injured. Adrenal and renal trauma is less frequent in NAT and is generally seen with multiple other injuries. Hypoperfusion complex is a constellation of abdominal CT findings that indicates current or impending decompensated shock and is most often due to severe neurologic impairment in NAT. Although abdominal injuries in NAT are relatively uncommon, knowledge of injury patterns and their imaging appearances is important for patient care and protection.

Acute rib fracture diagnosis in an infant by US: a matter of child protection.

Rib fractures in infants and children are highly specific for inflicted injury in the absence of a major accidental injury or underlying bone disorder. We present a 9-week-old infant diagnosed with an acute rib fracture by US at the site where physicians palpated chest wall crepitus when no rib fractures had been visualized on the skeletal survey, including oblique views of the ribs. Based on the US diagnosis of the acute rib fracture the infant was taken into protective custody. Follow-up skeletal survey 2 weeks later revealed healing fractures of the left 6th and 7th posterolateral ribs and right 7th, 8th and 9th anterolateral ribs. We were unable to locate previous reports describing the diagnosis of rib fractures in infants by US.

Adenomyotic cyst of the uterus in an adolescent.

Cystic adenomyosis is a rare form of adenomyosis of the uterine myometrium that has been described in older adults. This condition has not previously been reported in the pediatric radiology literature. In this case report, we describe an adenomyotic cyst in an adolescent girl that was imaged with US, CT, and MR and proved by surgical pathology. Understanding of the radiologic features of cystic adenomyosis is important for noninvasive diagnosis and effective medical/surgical management.

Acute lymphoblastic leukemia of the skin and subcutaneous tissues; the first manifestation of disease in a 6-month-old infant: a case report with literature review.

Leukemic infiltrate involving the skin and subcutaneous tissue was the first manifestation of disease in a 6-month-old female infant. Knowledge of age-related distribution patterns of the red (cellular) and yellow (fatty) marrow is crucial for the interpretation of magnetic resonance imaging (MRI) studies. Diffusely decreased signal intensity throughout the bone marrow on the T1-weighted images specifically involving the epiphyseal ossification centers in infants 6 months after their appearance should be suggestive of a marrow infiltrative/replacement process. Correlation with the peripheral blood smear and bone marrow aspirate are necessary for the diagnosis of leukemia.