Common subclinical hypothyroidism during Whipple's disease.

BACKGROUND: Classic Whipple's disease is caused by T. whipplei and likely involves genetic predispositions, such as the HLA alleles DRB1*13 and DQB1*06, that are more frequently observed in patients. T. whipplei carriage occurs in 2-4% of the general population in France. Subclinical hypothyroidism, characterized by high levels of TSH and normal free tetra-iodothyronine (fT4) dosage, has been rarely associated with specific HLA factors. METHODS: We retrospectively tested TSHus in 80 patients and 42 carriers. In cases of dysthyroidism, we tested the levels of free-T4 and anti-thyroid antibodies, and the HLA genotypes were also determined for seven to eight patients. RESULTS: In this study, 72-74% of patients and carriers were male, and among the 80 patients, 14 (17%) individuals had a high level of TSH, whereas none of the carriers did (p<0. 01). In the 14 patients with no clinical manifestations, the T4 levels were normal, and no specific antibodies were present. Four patients treated with antibiotics, without thyroxine supplementation, showed normal levels of TSHus after one or two years. One patient displayed a second episode of subclinical hypothyroidism during a Whipple's disease relapse five years later, but the subclinical hypothyroidism regressed after antibiotic treatment. HLA typing revealed nine alleles that appeared more frequently in patients than in the control cohort, but none of these differences reached significance due to the small size of the patient group. CONCLUSION: Regardless of the substratum, classic Whipple's disease could lead to subclinical hypothyroidism. We recommend systematically testing the TSH levels in patients with Whipple's disease.

Stability study of 81 analytes in human whole blood, in serum and in plasma.

OBJECTIVE: We studied the pre-analytical stability of 81 analytes based on the variables of delay before processing, storage as whole blood or serum/plasma, the storage temperature and the type of tube the sample was stored in. DESIGN AND METHODS: The mean difference between assays for samples from 10 subjects was calculated with the samples being kept under different storage conditions and for different times between sampling time and analysis: up to 24h for biochemistry, coagulation and hematology, and up to 72 h for hormonology. This difference was compared to the acceptable limits derived from the analytical and the intra individual biological variation. RESULTS: Most of the analytes investigated remained stable up to 24h under all storage conditions prior to centrifugation. However, some analytes were significantly affected either by delay, tube type or temperature, such as potassium, inorganic phosphorus, magnesium, LD, glucose, lactate, mean corpuscular volume, mean corpuscular hemoglobin, activated partial thromboplastin time, insulin, C-peptide, PTH, osteocalcin, C-telopeptide and ACTH. CONCLUSION: This study may be useful to help define acceptable delay times and storage conditions when a short time between sample collection and processing is not possible.

[Inventory of the use of natriuretic peptides in France]. / État des lieux de l'utilisation des peptides natriurétiques en France.

Since the introduction of routine assay for natriuretic peptides (NP), there is an increasing number of clinical applications for these assays. Due to the continuously increasing number of prescription of those tests, a reappraisal of the use of natriuretic peptide assays, namely BNP and NT-proBNP in France was necessary. This was achieved through a national survey to obtain a detailed description of NP prescription and realization by French laboratories. A questionnaire was sent in April 2010 to hospital and private clinical chemists. Statistical analysis of results concerned 584 answers. This survey demonstrated an equivalent use of BNP and NT-proBNP both in public or private laboratories together with a huge heterogeneity of tests used within labs. Medical prescription heterogeneity both in public or private sectors confirms the large implication of those tests in clinical diagnosis. These assays are not yet standardized, so clinicians and biologists should be very careful when interpreting the results for diagnostic or therapeutic monitoring.

Correlation of NT-proBNP with diastolic left ventricular function in elderly patients with ischemic stroke.

We tested the hypothesis that, in elderly survivors of ischemic stroke, high NT-proBNP levels are related with frequent diastolic dysfunction. We prospectively measured NT-proBNP, left ventricular ejection fraction (LVEF) and echographic parameters of diastolic function in 55 elderly consecutive patients, 6.8+/-2.6 days after acute ischemic stroke. We found that all the patients had systolic or diastolic dysfunction (14 had LVEF<50%, 26 mild diastolic dysfunction+LVEF > or = 50%, and 15 moderate or severe diastolic dysfunction+LVEF > or = 50%). The most powerful predictors of NT-proBNP were LVEF (R=0.38, p=0.004) and ratio of mitral E to the early diastolic velocity of the mitral annulus:E/E'(R=0.34, p=0.01).

Plasma adiponectin in heart transplant recipients.

BACKGROUND: The association between plasma adiponectin and metabolic syndrome may be impaired in heart transplant recipients, since renal failure is frequent among these patients. Thus, we studied the relationship between metabolic syndrome and plasma adiponectin in transplanted heart recipients. METHODS: Ninety-five heart transplant recipients were prospectively included 8.3 +/- 5.6 yr after transplantation in this cross-sectional study. All patients had physical examination, echocardiography or routine biennial coronary angiography, and laboratory measurements. RESULTS: Metabolic syndrome was found in 31% of these patients. Plasma adiponectin was significantly lower in patients with metabolic syndrome (12.5 +/- 8.3 microg/mL) than in patients without (16.7 +/- 9.4 microg/mL, p = 0.03). Adiponectin levels were usually in the normal or high range (< 4 microg/mL in only two patients). Low creatinine clearance was associated with higher plasma adiponectin (R=-0.26, p = 0.01). Plasma adiponectin was not significantly different between the 28 patients with angiographic evidence of graft vasculopathy (13.9 +/- 9.5 microg/mL) and the 67 patients without (16.1 +/- 9.1 microg/mL, p = 0.3). CONCLUSIONS: Contrasting with a high frequency of metabolic syndrome in these patients, adiponectin levels were usually in the normal or high range, probably as a consequence of renal failure. This suggests that adiponectin is not a major determinant for insulin resistance among these patients.

Cardiac troponins I and T in hemodialysis patients without acute coronary syndrome.

BACKGROUND: There is a reluctance to use cardiac troponins (cTn) for the monitoring of acute coronary syndrome (ACS) in hemodialysis (HD) patients because renal failure per se is thought to lead to increased cTn levels. The aim of this study was to analyse the proportion of patients with increased cTn levels in HD patients without ACS. METHODS: cTnI was measured with the AccuTnI(trade mark) from Beckman (cTnI-B) and Troponin I Stat(trade mark) from Dade Behring (cTnI-DB) assays; cTnT was measured with the third generation assay from Roche. The study included 105 HD patients. The clinical outcomes were determined after 2.5 years. RESULTS: Considering the receiver operator characteristic (ROC) cutoff, the proportion of patients with elevated cTnI-B, cTnI-DB and cTnT levels was respectively 2%, 3% and 27%. The proportion of patients with abnormal cTn values increased when a lower cutoff value was considered, based on the 99th percentile of a reference population with a coefficient of variation of less than 10% (99th percentile-10% CV cutoff). The proportion of patients with elevated values did not differ before and after the HD session. The 2.5 years mortality was associated with increased levels of cTnT but not with increased levels of cTnI. CONCLUSIONS: When the ROC cutoff is applied, cTnI assays are suitable for the monitoring of ACS in HD patients. cTnT could lead to false positive diagnosis of myocardial infarction, however it is predictive of long-term mortality. The 99th percentile-10% CV cutoff does not seem appropriate in HD patients.

NH2 terminal pro-brain natriuretic peptide plasma level as an early marker of prognosis and cardiac dysfunction in septic shock patients.

OBJECTIVE: To investigate N-terminal pro-brain natriuretic peptide (NT-proBNP) level as a prognostic factor and a marker of myocardial dysfunction in patients with septic shock. DESIGN: Prospective observational study. SETTING: Intensive care unit. SUBJECTS: A total of 39 patients diagnosed with septic shock and requiring mechanical ventilation. MEASUREMENTS AND MAIN RESULTS: Demographic, hemodynamic, respiratory, and biological data (notably NT-proBNP, lactate, and cardiac troponin I) were collected at inclusion and every 12 hrs. The independent factors for death were higher Sequential Organ Failure Assessment score in the 24-hr period after inclusion (odds ratio, 4.7; 95% confidence interval, 1.15-19.3) and the highest NT-proBNP level in the 24-hr period after inclusion (odds ratio, 1.12 per 1000 pg/mL increase; 95% confidence interval, 1.05-1.26). An NT-proBNP of >13,600 pg/mL predicted intensive care unit mortality with an accuracy of 77%. Area under the receiver operating characteristic curve was 0.8 (p = .002; 95% confidence interval, 0.66-0.93). NT-proBNP levels were over the accepted normal range in all patients. Values were highest between 24 and 36 hrs after onset of septic shock and were significantly higher in nonsurvivors at each time between inclusion and day 7. The lowest left ventricular stroke work index of the first 24-hr period after inclusion was the only factor that independently influenced higher NT-proBNP levels at the same time (odds ratio, 0.91; 95% confidence interval, 0.84-0.98). CONCLUSION: NT-proBNP seems to be an early factor of prognosis and myocardial dysfunction in patients with septic shock.

Usefulness of N-terminal-pro-brain natriuretic peptide levels in predicting survival in heart transplant recipients.

We evaluated the prognostic value of plasma N-terminal-pro-brain natriuretic peptide (NT-pro-BNP) in 71 transplanted heart recipients during a 38 +/- 2 month follow-up. The negative predictive value of NT-pro-BNP levels

Aminoterminal pro-brain natriuretic peptide and ventricular filling pressures in heart transplant recipients.

We tested the hypothesis that, in heart transplant recipients, plasma aminoterminal pro-brain natriuretic peptide (NT-proBNP) dosage is useful for diagnosis of high ventricular loading pressures in the absence of systolic dysfunction. We studied 60 consecutive transplanted heart recipients without systolic dysfunction at 1 to 16 years after transplantation. We found that, in these patients with frequent high ventricular filling pressures, plasma NT-proBNP was highly correlated with creatininemia and not correlated with ventricular loading pressures. These results do not support the hypothesis that NT-proBNP is useful for diagnosis of isolated diastolic dysfunction in transplanted heart recipients.