The sensitivity of interferon-gamma release assays is not compromised in tuberculosis patients with diabetes.

SETTING AND OBJECTIVES: the sensitivity of the interferon-gamma release assays (IGRAs) in the detection of Mycobacterium tuberculosis infection or disease may be affected by immune dysregulation in diabetes. As millions of type 2 diabetes patients are at risk for tuberculosis (TB) worldwide, it is important to determine if the sensitivity of IGRAs is compromised in this vulnerable population. DESIGN: the sensitivity of the IGRAs QuantiFERON®-TB Gold (QFT-G) and T-SPOT®.TB was evaluated among specimens from newly diagnosed adults with microbiologically confirmed TB with and without diabetes. We also evaluated the association between QFT-G results and diabetes-associated conditions (dyslipidemia, obesity). RESULTS: QFT-G sensitivity was 70% among TB patients. Patients with diabetes, chronic hyperglycemia or overweight/obesity were more than twice as likely to have positive test results in multivariate models (P < 0.05). Low high-density lipoprotein cholesterol or high triglycerides were not associated with assay results. In a separate group of TB patients (n = 43), T-SPOT.TB was 93% sensitive, with similar performance in patients with and without diabetes. CONCLUSION: IGRA sensitivity is not compromised by diabetes in TB patients. Accordingly, IGRAs may also be suitable for diagnosing TB infection in diabetes patients, which is required to assess TB risk.

Effect of myotonia induced by anthracene-9-carboxylic acid on mitochondrial calcium, plasma creatinine-phosphokinase and aldolase activity in the rat.

The frequent association of myotonia with dystrophy and the knowledge that calcium is increased in injured skeletal muscle cells suggest a possible relationship between cell calcium and myotonic alterations. This investigation has been performed to study the role of calcium in experimental myotonia induced by anthracene-9-carboxylic acid (9-AC) in rats treated with several regimens of food and exercise. Thirty-two rats were divided into 4 groups of 8 rats each, one control and 3 experimental groups. The treatments included caffeine plus exercise (group 2), and a calcium-rich diet (group 3); these procedures were designed to increase intracellular calcium; another group was treated with 9-AC as a myotonia-inducer (group 4). The treatment for all groups lasted 60 days. No significant differences in plasma sodium, potassium, chloride and calcium between control and experimental groups were observed. Whole muscle calcium in wet tissue samples did no change with any treatment. On the contrary, mitochondrial calcium showed a significantly higher concentration in group 3 and 4. CPK and aldolase activities in groups 1, 2 and 3 were similar; but in group 4 these enzyme activities were significantly higher (p less than 0.05). The electrical and mechanical responses were not altered in any rat with any experimental treatment. Our data suggest that myotonia is a predisposing factor for an altered mitochondrial calcium homeostasis in this model; in addition, the enzyme activities of CPK and aldolase were increased in the rats of group 4 implicating that myotonia is a crucial factor in the development of enzymatic abnormalities.(ABSTRACT TRUNCATED AT 250 WORDS)