ABSTRACT
Circulating vitamin D is found in various forms: 25-hydroxyvitamin D or calcidiol, majority circulating form, is a "pro-hormon" which will be converted to 1,25-dihydroxyvitamin D or calcitriol, hormone corresponding to vitamin D active form. While determination of 25-hydroxyvitamin D serum levels reflects vitamin D status of patients, determination of 1,25-dihydroxyvitamin D serum level is only indicated in rare cases of suspected hypersensitivity vitamin D in children or of sarcoidosis in adults. There are too many confusion between these two vitamin forms, resulting in inappropriate prescription of 1,25-dihydroxyvitamin D. Here, we describe a case of hypersensitivity to vitamin D by mutation of CYP24A1. We propose to review the interest of 1,25-dihydroxyvitamin D assay in different pathologies, to describe the assay techniques and remind the good prescribing practices of this parameter.
Subject(s)
Hypercalcemia/diagnosis , Hypercalcemia/genetics , Vitamin D3 24-Hydroxylase/genetics , Vitamin D/analogs & derivatives , Female , Humans , Infant , Mutation , Nephrocalcinosis/etiology , Vitamin D/metabolismABSTRACT
Imaging technological advances and widespread use of abdominal imaging have led to the identification of an increasing number of adrenal incidentalomas in the last decades. Causes of these adrenal masses are multiple, but the most common etiology is the non-functional adenoma. Although in most cases, these masses are benign and non-functional, clinicians have to perform biochemical testing for subclinical cushing's syndrome, pheochromocytoma or primary hyperaldosteronism. This screening is essential for their etiological diagnosis and therapeutic management. We report in this article the biological approach to detect secretory activity of adrenal incidentalomas and the diagnostic accuracy of the biochemical tests used.
Subject(s)
Adrenal Gland Neoplasms/diagnosis , Diagnostic Techniques, Endocrine , Hormones/blood , Adrenal Gland Neoplasms/blood , Adrenal Gland Neoplasms/etiology , Adult , Algorithms , Female , Humans , Middle AgedABSTRACT
BACKGROUND: The aim of this study was to evaluate the prevalence of beta-lactamase-producing Capnocytophaga isolates in young children hospitalized in the Pediatric Oncology Department of Hôpital Sud (Rennes, France) over a ten-year period (1993-2002). METHODS: In neutropenic children, a periodic survey of the oral cavity allows a predictive evaluation of the risk of systemic infections by Capnocytophaga spp. In 449 children with cancer, 3,053 samples were collected by oral swabbing and plated on TBBP agar. The susceptibility of Capnocytophaga isolates to five beta-lactams was determined. RESULTS: A total of 440 strains of Capnocytophaga spp. were isolated, 309 (70%) of which were beta-lactamase producers. The beta-lactamase-producing strains were all resistant to cefazolin, 86% to amoxicillin, and 63% to ceftazidime. The proportion of strains resistant to third-generation cephalosporins remained high throughout the ten-year study, while susceptibility to imipenem and amoxicillin combined with clavulanic acid was always conserved. CONCLUSION: These results highlight the risk of antibiotic failure in Capnocytophaga infections and the importance of monitoring immunosuppressed patients and testing for antibiotic susceptibility and beta-lactamase production.
