Clinical Course and Unique Features of Silent Corticotroph Adenomas.

OBJECTIVE: Silent corticotroph adenomas (SCAs) behave more aggressively than other non-functioning adenomas (NFAs). This study aims to expand the body of knowledge of the behavior of SCAs. METHODS: Retrospective analysis of 196 non-corticotroph NFAs and 20 SCAs from 2012-2017 was completed. Demographics, clinical presentation, imaging, and biochemical data were gathered. The primary endpoint was to identify features of SCAs versus other NFAs that suggest aggressive disease, including pre-surgical comorbidities, postoperative complications, extent of tumor, and recurrence. Golden-angle radial sparse parallel (GRASP) magnetic resonance images were obtained from a subset of SCAs and NFAs. Permeability data were obtained to compare signal-to-time curve variation between the 2 groups. RESULTS: With multivariate regression analysis, SCAs showed higher rates of hemorrhage on preoperative imaging than NFAs (P = 0.017). SCAs presented more frequently with headache (P = 0.012), vision changes (P = 0.041), and fatigue (P = 0.028). SCAs exhibited greater extent of tumor burden with increased occurrence of stalk deviation (P = 0.008), suprasellar invasion (P = 0.021), optic chiasm compression (P = 0.022), and cavernous sinus invasion (P = 0.015). On GRASP imaging, SCAs had significantly lower permeability of contrast than NFAs (P = 0.001). Thirty percent of SCAs were noted to recur with a 14% recurrence rate in other NFAs, though this difference was not of statistical significance (P = 0.220). CONCLUSIONS: SCAs exhibit features of more aggressive disease. Interestingly, a significant increase in recurrence was not seen despite these features. The results of this study support the growing body of evidence that SCAs behave more aggressively than other NFPAs and was able to provide some insight into factors that may contribute to recurrence.

CLINICAL PRACTICE PATTERNS FOR POSTOPERATIVE WATER BALANCE AFTER PITUITARY SURGERY.

Objective: Abnormalities of water and sodium balance, including diabetes insipidus and the syndrome of inappropriate antidiuretic hormone (SIADH), are common complications of transsphenoidal surgery. Postoperative practice patterns vary among clinicians, and no consensus guidelines exist to direct their monitoring and management. We aimed to identify and compare practice patterns regarding the evaluation and management to these postoperative complications. Methods: A questionnaire was utilized to capture demographic data and practice habits in the postoperative setting. Respondents were members of the Pituitary Society, an international organization comprised of clinicians and researchers dedicated to the study of pituitary disease. Results: Eighty-six respondents completed at least part of the survey. The geographic distribution of respondents was roughly even between American and non-American practitioners. The majority of respondents practiced at academic institutions (67.4%), worked in multidisciplinary teams (88.4%), and possessed significantly greater than 10 years of clinical experience (71%). Compared to non-American practitioners, American practitioners described a shorter length of stay postoperatively (P<.001) and prescribed more restrictive volume recommendations for postoperative SIADH (P = .0035). Early career clinicians (less than 10 years in practice) checked first postoperative sodium level earlier than later career clinicians (P = .010). Conclusion: Water and sodium dysregulation are common following transsphenoidal surgery, but their management is not well-standardized in clinical practice. We created a questionnaire to define and compare practice patterns. Most respondents practice in academic settings in multidisciplinary teams. The length of clinical experience did not significantly impact practice habits. Practice location influenced length of stay postoperatively and fluid restriction in SIADH. Abbreviations: AVP = arginine vasopressin; DI = diabetes insipidus; LOS = length of stay; SIADH = syndrome of inappropriate antidiuretic hormone.

Erroneous thyroid diagnosis due to over-the-counter biotin.

OBJECTIVES: Biotin is a component of the vitamin B complex used in standard immunoassays to detect serum levels of various hormones and non-hormones, including thyrotropin (TSH) and thyroxine. These assays involve a strong bond between streptavidin and biotin, which serves as an anchor for measured analytes. Large doses of exogenous biotin for the treatment of certain medical conditions have resulted in assay interference, causing TSH to be spuriously lowered. Smaller doses of biotin found in dietary supplements also have caused assay interference. METHODS: We describe four cases in which over-the-counter (OTC) biotin caused erroneous thyroid diagnosis and clinical confusion in patients with preexisting thyroid disease. Serum TSH and thyroxine were measured by the Vitros 5600 assay. CONCLUSIONS: Although the biotin-streptavidin interaction is sensitive for detecting serum levels of TSH, it is subject to interference by exogenous biotin at levels found in OTC products. The widespread use of OTC biotin for cosmetic purposes can adversely affect the diagnosis of the entire spectrum of functional thyroid disorders. Physicians must carefully and routinely question for the use of biotin before thyroid function testing.

Objective cardiac markers and cerebrovascular lesions in Indian seniors.

Cardiovascular risk factors are implicated in cerebrovascular disease, resulting in cognitive impairment. This study investigated the relationship between objective cardiac markers and cerebral changes in older Indian adults with and without dementia. Dementia patients with major electrocardiographic (EKG) abnormalities were 8.19 times more likely to have evidence of stroke on magnetic resonance imaging (MRI) compared with patients with no EKG abnormalities (p<.05). The relationship between major EKG abnormalities and stroke on MRI was not significant for patients without dementia. Objective cardiac markers may identify MRI cerebrovascular lesions in patients with dementia, and thus guide neuroimaging allocation in resource-poor areas.