Search

Cogan's syndrome, typified by the combination of interstitial keratitis and immune-mediated sensorineural hearing loss, is a rare condition, and commonly associated with a diagnostic delay. Using a standard search protocol, we review the literature to date, focusing on a number of key areas pertaining to diagnosis, presentation and treatment. Using a case illustration of atypical disease which led to fulminant aortic regurgitation, we highlight the need for continued and collaborative research in order to identify negative prognostic factors and thus tailor therapeutic regimens. Atypical Cogan's syndrome is more commonly associated with systemic manifestations than typical disease, and may be refractory to immunosuppressive treatment. We discuss the application of laboratory (e.g antibodies targeting inner ear antigens) and radiological (PET-CT) aids to disease confirmation and detection of sub-clinical vascular inflammation. As illustrated by the included case description, some patients remain refractory to intense immunosuppression and delineation of adverse prognostic factors which may direct treatment, perhaps including the use of PET-CT, will contribute in the future to improving patient outcomes.

Mild hyponatremia has traditionally been considered benign, but it may be associated with gait and attention deficits and an increased risk of falls that may result in fracture. A retrospective study was conducted to quantify the association of hyponatremia with fracture occurrence and to examine whether this relationship is independent of osteoporosis.This study analyzed 1408 consecutive female patients who underwent bone mineral density measurement (Lunar IDXA) between September 1, 2006 and April 11, 2007 and who had available laboratory data. Self reported fracture occurrence was confirmed by radiology report or attendance at a fracture clinic. The significance and independence of the association of hyponatremia with fracture was quantified using logistic regression.The mean (SD) serum sodium ([Na(+)]) was 140.6 (3.0) mmol/L; 59 (4.2%) had [Na(+)]135 mmol/L. Forty-five percent of subjects were osteoporotic and 18% had a prior fracture. Hyponatremia was present in 8.7% of those with versus 3.2% of those without a confirmed fracture (P0.001). On multivariate logistic regression analysis controlling for age, T-score, chronic kidney disease stage, osteoporotic risk factors (amenorrhea, family history, regular steroid use, smoking history, alcohol use, history of liver disease, and low-calcium diet), and osteoporosis treatments (calcium and vitamin D supplements, antiresorptives, and hormonal replacement therapy), [Na(+)]135 versus [Na(+)]or= 135 mmol/L remained significantly and independently associated with fracture occurrence (P0.01).Mild hyponatremia may be a readily identifiable and potentially modifiable risk factor for fracture.