BackgroundTo determine the prevalence and diagnostic value of pelvic enthesitis on MRI of the sacroiliac (SI) joints in enthesitis related arthritis (ERA).MethodsWe retrospectively studied 143 patients aged 6–18 years old who underwent MRI of the SI joints for clinically suspected sacroiliitis between 2006–2014. Patients were diagnosed with ERA according to the International League of Associations for Rheumatology (ILAR) criteria. All MRI studies were reassessed for the presence of pelvic enthesitis, which was correlated to the presence of sacroiliitis on MRI and to the final clinical diagnosis. The added value for detection of pelvic enthesitis and fulfilment of criteria for the diagnosis of ERA was studied.ResultsPelvic enthesitis was seen in 23 of 143 (16 %) patients. The most commonly affected sites were the entheses around the hip (35 % of affected entheses) and the retroarticular interosseous ligaments (32 % of affected entheses). MRI showed pelvic enthesitis in 21 % of patients with ERA and in 13 % of patients without ERA. Pelvic enthesitis was seen on MRI in 7/51 (14 %) patients with clinically evident enthesitis, and 16/92 (17 %) patients without clinically evident enthesitis. In 7 of 11 ERA-negative patients without clinical enthesitis but with pelvic enthesitis on MRI, the ILAR criteria could have been fulfilled, if pelvic enthesitis on MRI was included in the criteria.There is a high correlation between pelvic enthesitis and sacroiliitis, with sacroiliitis present in 17/23 (74 %) patients with pelvic enthesitis.ConclusionsPelvic enthesitis may be present in children with or without clinically evident peripheral enthesitis. There is a high correlation between pelvic enthesitis and sacroiliitis on MRI of the sacroiliac joints in children. As pelvic enthesitis indicates active inflammation, it may play a role in assessment of the inflammatory status. Therefore, it should be carefully sought and noted by radiologists examining MRI of the sacroiliac joints in children.

BackgroundThe Assessment of Spondyloarthritis International Society (ASAS) definition for a ‘positive’ Magnetic Resonance Imaging (MRI) for sacroiliitis is well studied and validated in adults, but studies about the value of this definition in children are lacking. The aim of this study is to evaluate whether the adult ASAS definition of a positive MRI of the sacroiliac joints can be applied to children with a clinical suspicion of Juvenile Spondyloarthritis (JSpA).MethodsTwo pediatric musculoskeletal radiologists blinded to clinical data independently retrospectively reviewed sacroiliac (SI) joint MRI in 109 children suspected of sacroiliitis. They recorded global impression (sacroiliitis yes/no) and whether the adult ASAS definition for sacroiliitis was met at each joint. This was compared to gold-standard clinical diagnosis of JSpA. Additionally, MRI were scored according to’adapted’ ASAS definitions including other features of sacroiliitis on MRI.ResultsJSpA was diagnosed clinically in 47/109 (43%) patients. On MRI, sacroiliitis was diagnosed by global assessment in 30/109 patients, of whom 14 also fulfilled ASAS criteria. No patients with negative global assessment for sacroiliitis fulfilled ASAS criteria. Sensitivity (SN) for JSpA was higher for global assessment (SN = 49%) than for ASAS definition (SN = 26%), but the ASAS definition was more specific (SP = 97% vs. 89%). Modifying adult ASAS criteria to allow bone marrow edema (BME) lesions seen on only one slice, synovitis or capsulitis, increased SN to 36%, 32% and 32% respectively, only slightly lowering SP. Including structural lesions increased SN to 28%, but lowered specificity to 95%.ConclusionThe adult ASAS definition for sacroiliitis has low sensitivity in children. A pediatric-specific definition of MRI-positive sacroiliitis including BME lesions visible on one slice only, synovitis and/or capsulitis may improve diagnostic utility, and increase relevance of MRI in pediatric rheumatology practice.

Case presentation We report for the first time a synchronous papillary and follicular thyroid carcinoma in a 12-year-old girl presenting with a large (5 cm diameter) left thyroid nodule, an increased left and right upper pole technetium tracer uptake at scintigraphy and hyperthyroidism. The uptake at the right lobe was explained by the crossing of the left nodule to the right site of the neck at Computed Tomography (CT) scanning. Background Although thyroid nodules are less common in children than in adults, there is more vigilance required in children because of the higher risk of malignancy. According to literature, about 5% of the thyroid nodules in adults are malignant versus 20–26% in children. The characteristics of 9 other pediatric cases with a differentiated thyroid carcinoma presenting with a toxic nodule, which have been reported during the last 20 years, are summarized. A nodular size of more than 3.5 cm and female predominance was a common finding. Conclusions The presence of hyperthyroidism in association with a hyperfunctioning thyroid nodule does not rule out thyroid cancer and warrants careful evaluation, even in the absence of cervical lymph node invasion.

Cobalamin or vitamin B12 (vitB12) is involved in DNA synthesis, haematopoiesis and myelinisation. Consequently, vitB12 deficiency causes various symptoms, such as megaloblastic anaemia, neurologic signs or pancytopenia. Despite possible severe symptoms, vitB12 deficiency can present asymptomatically. We report six paediatric patients with different aetiologies of vitB12 deficiency ranging from a subtle to a more overt presentation. VitB12 deficiency is a diagnostic challenge due to the lack of consensus on normal values of vitB12 and its co-markers (folate, holotranscobalamin, methylmalonic acid, homocysteine) and the lack in specificity and sensitivity of the serum vitB12 analysis. All cases were treated with parenteral vitB12. Last decades, evidence supporting high dose oral treatment being as effective as the intramuscular (IM) therapy, also in children, is growing.