Updated reference intervals for urine normetanephrine have no effect on test sensitivity but fewer false positives.

OBJECTIVE: We previously highlighted the problem of frequent false positives in 24 h urine normetanephrine(UNM) measurements owing to reference intervals that are inappropriately low for the population being screened for pheochromocytoma. Using a large population database, we devised new age-stratified reference intervals for the 24 h UNM test that were higher compared to previous. However, it was uncertain as to whether this would compromise test sensitivity for true pheochromocytoma cases. DESIGN AND METHODS: Retrospective analysis of all pheochromocytoma cases from a recently constructed provincial registry. All confirmed cases had their diagnostic UNM results retrospectively re-analysed according to the newly proposed UNM reference intervals to determine the percentage and phenotype of cases that might have been theoretically missed with the new reference range. RESULTS: After excluding pediatric and non-secretory head and neck paragangliomas, there were 60 confirmed pheochromocytoma cases. Using prior reference intervals, 51/60 (85%) had an abnormally high UNM. Of the 9 with normal UNM, 4 had a high urine metanephrine(UMN), 5 had normal levels of both UNM and UMN such that 55/60 had abnormal test results, representing the historical combined test sensitivity of 92%. Using the proposed reference interval, 43/60 (72%) had high UNM results. Of the 17 with normal UNM, 12 had high UMN, 5 had normal levels of both UNM and UMN. Therefore, 55/60 patients had had elevations in either UNM or UMN, corresponding to an identical combined test sensitivity of 92%. CONCLUSIONS: Reference intervals for UNM derived from actual clinical population screening data are higher than in traditional healthy volunteers. Use of these more appropriate reference intervals can significantly reduce the false positive rate without compromising test sensitivity for true pheochromocytoma.

Barriers and Facilitators to Using Statins: A Qualitative Study With Patients and Family Physicians.

BACKGROUND: Despite their proven efficacy to reduce cardiovascular disease, statin medication use remains low in individuals at high risk of cardiovascular disease considering their widespread availability and safety. Our objective was to explore the perspectives of patients and family physicians with regard to the barriers and facilitators of statin use in primary care. METHODS: In this qualitative descriptive study, we conducted 2 focus groups with patients (number, n = 8/6) and individual semistructured interviews with family physicians (n = 17) from community settings. Interviewers asked participants about barriers to and facilitators of statin use. Focus groups and interviews were digitally recorded, transcribed, and analyzed in duplicate using conventional content analysis. RESULTS: Patients were averse to taking statins for a variety of reasons: medication avoidance and burden; inadequate buy-in for statin therapy; and difficulty remembering to take statins regularly. Family physicians perceived similar barriers and reported other barriers: lack of resources such as inadequate tracking systems; specialist-primary care provider guideline discordance; and lack of continuity and relationship. Patients expressed that key facilitators were patient education and support; splitting tablets to increase cost-effectiveness; and changing to a different statin or lower dose in those with side effects. Family physicians described several similar strategies to facilitate therapy as well as shared decision making and clinical decision support tools as enablers for improvement. CONCLUSIONS: We identified several important barriers to and facilitators of statin use at the patient and prescriber level. This information offers insight into strategies to improve statin use and the development of innovative programs and interventions.

INTRODUCTION: En dépit de leur efficacité prouvée pour réduire les maladies cardiovasculaires, l'utilisation des statines reste faible chez les individus exposés à un risque élevé de maladies cardiovasculaires si l'on considère leur grande disponibilité et leur innocuité. Notre objectif était d'examiner les perspectives des patients et des médecins de famille en ce qui concerne les obstacles et les facilitateurs de l'utilisation des statines en soins primaires. MÉTHODES: Dans la présente étude qualitative descriptive, nous avons mené 2 groupes de discussion composés de patients (nombre, n = 8/6) et des entrevues semi-structurées individuelles avec des médecins de famille (n = 17) en milieu communautaire. Les intervieweurs ont demandé aux participants quels étaient les obstacles et les facilitateurs de l'utilisation des statines. Les groupes de discussion et les entrevues étaient enregistrés numériquement, transcrits et analysés en duplicata à l'aide de l'analyse de contenu traditionnelle. RÉSULTATS: Les patients se sont opposés à la prise de statines pour plusieurs raisons : l'évitement et le fardeau des médicaments, l'adhésion insuffisante au traitement par statines et la difficulté à se souvenir de prendre régulièrement les statines. Les médecins de famille ont perçu des obstacles similaires et ont rapporté d'autres obstacles dont le manque de ressources telles que les systèmes de suivi inadéquats, la divergence entre les orientations des spécialistes et des prestataires de soins primaires, et le manque de continuité et de relation. Les patients ont exprimé que les principaux facilitateurs étaient l'éducation et le soutien offerts aux patients; le fractionnement des comprimés pour améliorer l'efficience; le changement vers une statine différente ou une dose plus faible chez ceux qui présentent des effets secondaires. Les médecins de famille ont décrit plusieurs stratégies semblables pour faciliter le traitement ainsi que la prise de décision partagée et les outils d'aide à la décision clinique qui facilitent l'amélioration. CONCLUSIONS: Nous avons déterminé plusieurs obstacles et facilitateurs importants de l'utilisation des statines au point de vue du patient et du prescripteur. Ces informations offrent un aperçu des stratégies pour améliorer l'utilisation des statines et l'élaboration d'interventions et de programmes innovateurs.

Evaluation and management of the child with hypothyroidism.

BACKGROUND: Thyroid hormones are critical for early neurocognitive development as well as growth and development throughout childhood. Prompt recognition and treatment of hypothyroidism is, therefore, of utmost importance to optimize physical and neurodevelopmental outcomes. DATA SOURCES: A PubMed search was completed in Clinical Queries using the key terms "hypothyroidism". RESULTS: Hypothyroidism may be present at birth (congenital hypothyroidism) or develop later in life (acquired hypothyroidism). Thyroid dysgenesis and dyshormonogenesis account for approximately 85% and 15% of permanent cases of congenital primary hypothyroidism, respectively. More than 95% of infants with congenital hypothyroidism have few, if any, clinical manifestations of hypothyroidism. Newborn screening programs allow early detection of congenital hypothyroidism. In developed countries, Hashimoto thyroiditis is the most common cause of goiter and acquired hypothyroidism in children and adolescents. Globally, iodine deficiency associated with goiter is the most common cause of hypothyroidism. Central hypothyroidism is uncommon and may be associated with other congenital syndromes and deficiencies of other pituitary hormones. Familiarity of the clinical features would allow prompt diagnosis and institution of treatment. CONCLUSIONS: To optimize neurocognitive outcome in infants with congenital hypothyroidism, treatment with levothyroxine should be started as soon as possible, preferably within the first 2 weeks of life. Children with acquired hypothyroidism should also be treated early to ensure normal growth and development as well as cognitive outcome. The target is to keep serum TSH < 5 mIU/L and to maintain serum free T4 or total T4 within the upper half of the age-specific reference range, with elimination of all symptoms and signs of hypothyroidism.

Gynecomastia in Infants, Children, and Adolescents.

BACKGROUND: Gynecomastia may occur physiologically in the neonatal period, during puberty, and in old age. It may also develop in association with various pathologic states. The challenge for the physician is to distinguish physiological gynecomastia from those with an underlying pathology. OBJECTIVE: To review in depth the pathophysiology, clinical manifestations, and treatment of gynecomastia. METHOD: A PubMed search was completed in Clinical Queries using the key term "gynecomastia". Patents were searched using the key term "gynecomastia" from www.google.com/patents, www.uspto.gov, and www.freepatentsonline.com. RESULTS: Gynecomastia is caused by an imbalance between the stimulatory effect of estrogen and the inhibitory effect of androgen at the breast tissue level. Clinically, gynecomastia is characterized by the presence of a firm or rubbery, discrete, subareolar ridge of glandular tissue that is symmetrical in shape, freely movable, and nonadherent to skin or underlying tissue. Since most cases of physiological gynecomastia regress spontaneously with time, reassurance is all that is necessary. For pathological gynecomastia, treatment should be directed at the underlying cause, if possible. If gynecomastia persists in spite of the above measures, pharmacologic therapy and reduction mammoplasty may be considered. Recent patents related to the management of gynecomastia are discussed. CONCLUSION: The majority of cases are physiological and do not require treatment other than reassurance. For pathological cases, the underlying cause should be treated if possible. If gynecomastia persists in spite of the above measures and treatment becomes necessary, tamoxifen is the treatment of choice. Reduction mammoplasty may be considered for resistant cases.

Evaluation and Management of Children with Thyrotoxicosis.

BACKGROUND: Uncontrolled thyrotoxicosis, especially in early infancy, may cause irreversible damage to the central nervous system as well as profound effects on the function of many organs. Thyrotoxicosis has multiple etiologies and treatment depends on the underlying etiology. An accurate diagnosis is essential so that appropriate treatment can be initiated without undue delay. OBJECTIVE: To review in depth the evaluation, diagnosis, and treatment of children with thyrotoxicosis. METHODS: A PubMed search was completed in Clinical Queries using the key terms "thyrotoxicosis" and "hyperthyroidism". The search strategy included meta-analysis, randomized controlled trials, clinical trials, observational studies, and reviews. Patents were searched using the key terms "thyrotoxicosis" and "hyperthyroidism" from www.freepatentsonline.com and www.google.com/patents. RESULTS: Graves' disease accounts for approximately 96% of pediatric cases of thyrotoxicosis. Other causes include Hashitoxicosis, toxic adenoma, toxic multinodular goiter, subacute granulomatous thyroiditis, acute suppurative thyroiditis, pituitary thyroid-stimulating hormone-secreting adenoma, pituitary thyroid hormone resistance, iodine-induced thyrotoxicosis, and drug-induced thyrotoxicosis. Familiarity of the clinical features would allow prompt diagnosis and institution of treatment. The underlying cause of thyrotoxicosis should be treated if possible. Treatment options for Graves' disease include antithyroid medications, radioiodine therapy, and surgery. Recent patents related to the management of thyrotoxicosis are discussed. CONCLUSION: Currently, antithyroid medications are considered to be the initial treatment of choice for Graves' disease in the pediatric age group. Radioactive iodine treatment is generally used for children with poor compliance with antithyroid medications, children not in remission after 1 to 2 years of antithyroid medications, and children with a major adverse effect while receiving an antithyroid medication. Total or near-total thyroidectomy should be considered in children younger than 5 years of age who do not respond to or experience a major adverse effect to antithyroid medications. Surgery should also be considered in those with very large goiter, severe ophthalmopathy, pregnancy, persistent hyperthyroidism in spite of treatment with antithyroid medications and radioactive iodine, and personal preference.

A Case of Dilated Cardiomyopathy Associated with 3-Hydroxy-3-Methylglutaryl-Coenzyme A (HMG CoA) Lyase Deficiency.

3-hydroxy-3-methylglutaryl-coenzyme A (HMG CoA) lyase deficiency is an inborn error of metabolism characterized by impairment of ketogenesis and leucine catabolism resulting in an organic acidopathy. In 1994, a case of dilated cardiomyopathy and fatal arrhythmia was reported in a 7-month-old infant. We report a case of dilated cardiomyopathy in association with HMG CoA lyase deficiency in a 23-year-old man with the acute presentation of heart failure. To our knowledge, this is the first case reported in an adult.

Persistent Mongolian spots in Chinese adults.

Four Chinese females aged 21-35 years with Mongolian spots are reported. Two patients had the spots on their arms while the other two had the spots on their shoulders. The persistence of Mongolian spots in Chinese adults has not been previously reported.

Specificity of synapse formation between Lymnaea heart motor neuron and muscle fiber is maintained in vitro in a soma-muscle configuration.

Precise neuronal connectivity during development is subservient to all nervous system functions in adult animals. However, the cellular mechanisms that mastermind this neuronal connectivity remain largely unknown. This lack of fundamental knowledge regarding nervous system development is due in part to the immense complexity of mammalian brain, as cell-cell interactions between defined sets of pre- and postsynaptic partners are often difficult to investigate directly. In this study, we developed a novel model system which has allowed us to reconstruct synapses between identified motor neurons and their target heart muscle cell in a soma-muscle configuration. Utilizing this soma-myocardial cell synapse model, we demonstrate that synapses between somata and heart muscle cells can be reconstructed in cell culture. The soma-myocardial cell synapses required 12-24 h to develop and thus differed temporally from conventional neuromuscular synapses (seconds to a few minutes). We also demonstrate that the synapses are target cell-type-specific and are most likely independent of transmitter phenotypic characteristics of presynaptic neurons.