Diagnostic value of MRI of the sacroiliac joints in juvenile spondyloarthritis

Early diagnosis of spondyloarthritis (SpA) is becoming more important as new medical treatment options have become available to treat inflammation and delay progression of the disease. Increasingly, magnetic resonance imaging (MRI) of the sacroiliac joints is obtained for early detection of inflammatory changes, as it shows active inflammatory and structural lesions of sacroiliitis long before radiographic changes become evident. MRI of the sacroiliac joints in children is a useful tool for suspected juvenile spondyloarthritis (JSpA), even though it is not yet included in the current pediatric classification systems. Recognizing MRI features of pediatric sacroiliitis is a challenge. As most radiologists are not familiar with the normal MRI appearance of the pediatric sacroiliac joint, clear definitions are mandatory. Actually, the adult Assessment of Spondyloarthritis International Society (ASAS) definition for sacroiliitis needs some adaptations for children. A proposal for a possible pediatric-specific definition for active sacroiliitis on MRI is presented in this review. Furthermore, MRI without contrast administration is sufficient to identify bone marrow edema (BME), capsulitis, and retroarticular enthesitis as features of active sacroiliitis in JSpA. In selected cases, when high short tau inversion recovery (STIR) signal in the joint is the only finding, gadolinium-enhanced images may help to confirm the presence of synovitis. Lastly, we found 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 when examining MRI of the sacroiliac joints in children

A case of chronic recurrent multifocal osteomyelitis associated with Crohn's disease

Chronic recurrent multifocal osteomyelitis (CRMO) is an auto-inflammatory bone disease of unknown etiology, most commonly affecting the metaphysis of long bones, especially the tibia, femur and clavicle. The clinical spectrum varies from self-limited uni-or multi-focal lesions to chronic recurrent courses. Diagnosis is based on clinical, radiologic and pathological findings, is probably under-diagnosed due to poor recognition of the disease. A dysregulated innate immunity causes immune cell infiltration of the bones with subsequent osteoclast activation leading to sterile bone lesions. The molecular pathophyiology is still incompletely understood but association with other auto-inflammatory diseases such as inflammatory bowel disease (IBD), psoriasis, Wegener's disease, arthritis and synovitis, acne, pustulosis, hyperostosis and osteitis (SAPHO) syndrome is interesting. CRMO can precede the symptoms of the associated disease by several years. The bone remodeling caused by CRMO can cause permanent disability. We report the case of a 10-year-old boy with CRMO in association with Crohn's disease

Acute renal failure after vomiting in a teenager

We present the case of a 12 year old boy who presented to the emergency department because of vomiting and abdominal pain. Initial workup revealed risen creatinine (1,7mg/dl), hyponatriemia (131mmol/l), hypokaliemia (3,7mmol/l), hypochloremia (77mmol/l) and hyperphosphatemia (10,2mg/dl). Furthermore we observed increased corticomedullary differentiation echographically. Due to the atypical presentaion we decided to perform a renal biopsy which was suggestive for the presence of oxalate crystals in the lumina of some tubules. However a 24hour urine collection was normal for oxalate excretion and genetic tests were negative for the most common hyperoxaluria mutations (AGXT, GRHPR). Still the GFR was only partially recovered in the upcoming weeks. The patient was regurarly followed up at our outpatient clinic. We noted failure to thrive, several episodes of vomiting and dehydration paired with transient elevated creatinine. The boy was therefore diagnosed with secondary hyperoxaluria due to dehydration

Propylthioiracil induced ANCA-associated vasculitis in a 14 year-old girl

Background: Antineutrophil cytoplasmic antibodies (ANCAs) are the serologic hallmark of ANCA-associated primary small-vessel vasculitides (AAVs), but these antibodies have also been described in other autoimmune diseases such as inflammatory bowel diseases. Furthermore, different drugs are linked to the induction of ANCA, including propylthiouracil (PTU). However progression into clinical overt vasculitis is less common. Case-diagnosis/treatment: We describe the case of a young girl with Graves' disease presenting with fatigue, fever, episcleritis and arthritis. The unexpected double myeloperoxidase/proteinase 3-ANCA positivity triggered a multidisciplinary diagnostic work-up and resulted in the diagnosis of a clinically overt PTU-induced AAV. After PTU-withdrawal and treatment with high-dose corticosteroids, a favorable clinical and biochemical evolution was obtained. Conclusions: The use of PTU in the management of hyperthyroidism is not considered first-line treatment in Europe and is even less commonly used in children. Nevertheless, pediatricians should be aware of the possibility of PTU-induced AAV, especially in the presence of multiple ANCA reactivities. Therefore, the use of this drug should be weighed carefully in children

ASAS definition for sacroiliitis on MRI in SpA : applicable to children?

Background: The 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). Methods: Two 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 goldstandard clinical diagnosis of JSpA. Additionally, MRI were scored according to'adapted' ASAS definitions including other features of sacroiliitis on MRI. Results: JSpA 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%. Conclusion: The 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

Diagnositic value of pelvic enthesitis on MRI of the sacroiliac joints in enthesitis related arthritis

Background: To determine the prevalence and diagnostic value of pelvic enthesitis on MRI of the sacroiliac (SI) joints in enthesitis related arthritis (ERA). Methods: We 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. Results: Pelvic 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. Conclusions: Pelvic 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

Acht jaar ervaring met in-center nachtelijke hemodialyse bij kinderen

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Resilience factors in children with juvenile idiopathic arthritis and their parents : the role of child and parent psychological flexibility

Objective. Chronic pain is central to juvenile idiopathic arthritis (JIA) and is predictive of impaired functioning. Whereas most work has focused on identifying psychosocial risk factors for maladaptive outcomes, we explored the idea that child and parental psychological flexibility (PF) represent resilience factors for adaptive functioning of the child. We also explored differences between general vs pain-specific PF in contributing to child outcomes. Methods. Children with JIA (age eight to 18 years) and (one of) their parents were recruited at the Department of Pediatric Rheumatology at the Ghent University Hospital in Belgium. They completed questionnaires assessing child and parent general and pain-specific PF and child psychosocial and emotional functioning and disability. Results. The final sample consisted of 59 children and 48 parents. Multiple regression analyses revealed that child PF contributed to better psychosocial functioning and less negative affect. Child pain acceptance contributed to better psychosocial functioning, lower levels of disability, and lower negative affect, and also buffered the negative influence of pain intensity on disability. Bootstrap mediation analyses demonstrated that parental (general) PF indirectly contributed to child psychosocial functioning and affect via the child's (general) PF. Parent pain-specific PF was indirectly linked to child psychosocial functioning, disability, and negative affect via child pain acceptance. Conclusions. Our findings indicate that child and parental PF are resilience factors and that pain acceptance buffers the negative impact of pain intensity. Implications for psychosocial interventions that target (pain-specific) PF in children and parents are discussed