[Application and evaluation of urine measurement at different times methods for estimating salt intake].

Salt reduction is the most cost-effective population strategy to prevent and control hypertension and cardiovascular disease. Accurate measurement of salt intake is an important basis for implementing salt reduction interventions, while the urine sodium measurement is the most objective method to evaluate salt intake. According to different time spans, it is mainly divided into 24-h urine, overnight urine and spot urine collection methods. This article reviewed the application and evaluation of these three urine measurement methods, and compared their advantages and disadvantages. According to the accuracy and feasibility of different urine measurement methods, it is suggested that the 24-h urine collection method can be applied to the correlation study with small sample size, and the overnight urine method and the spot urine method can be applied to the daily population salt reduction interventions and monitoring activities.

[Novel biomarkers for latent tuberculosis infection by plasma proteomic profiling].

OBJECTIVE: To screen specific biomarkers for latent tuberculosis infection by comparing the plasma proteomic profiling between latent tuberculosis infection and healthy controls. METHODS: The plasma proteins from 15 cases with latent tuberculosis infection and 15 healthy controls were detected by the label-free quantitative proteomic technology. Differential expressed proteins were analyzed by GO, KEGG, and BiNGO analysis. Student's t test was used to analyze the differential expression between 2 groups. RESULTS: Twenty-three candidate proteins were identified, among which 15 proteins were downregulated (<0.5-fold at P<0.05) and 8 proteins were upregulated (>2.0-fold at P<0.05) in the latent tuberculosis infection group. Bioinformatic analysis revealed 3 proteins AAT, C3 and C4A to be the most significant. CONCLUSION: There were differential plasma protein profiles between latent tuberculosis infection and healthy controls. Candidate proteins AAT, C3 and C4A were promising biomarkers for discriminating cases with latent tuberculosis infection from healthy persons.

Modified cytospin slide microscopy method for rapid diagnosis of smear-negative pulmonary tuberculosis.

OBJECTIVE: To evaluate a modified method of the Ziehl-Neelsen stain and determine whether it improves the detection rate of acid-fast bacilli (AFB) in bronchoalveolar lavage fluid (BALF) specimens. DESIGN: Bronchoscopy of patients with suspected smear-negative pulmonary tuberculosis (PTB) patients was conducted to collect BALF to assess the efficacy and accuracy of the modified method for PTB diagnosis. RESULTS: A total of 106 BALF specimens was collected from 74 PTB patients on the basis of BALF samples that were culture-positive for Mycobacterium tuberculosis. When analysed by patient, the sensitivity and specificity of our modified method were respectively 87.8% and 99.6%, while the positive predictive (PPV) and negative predictive values (NPV) were respectively 98.5% and 96.8%. Conversely, the sensitivity of direct smears and concentrated smears was respectively 16.2% and 37.8%, with 100% specificity. On analysing 106 samples, the culture positivity rate of the direct smear and the concentrated smear methods was respectively 76.4%, 13.2% and 34%, while it was 91.5% for the modified method. CONCLUSION: The sensitivity of our modified method was significantly higher than that of direct or concentrated smears. Overall, the modified method improved the detection rate of AFB in BALF specimens, and provided an efficient and accurate diagnosis of PTB in patients with suspected smear-negative PTB.

Inadequate values from an interferon-gamma release assay for smear-negative tuberculosis in a high-burden setting.

OBJECTIVE: To examine the usefulness of an interferon-gamma release assay (IGRA) for the diagnosis of smear-negative tuberculosis (TB) in China. DESIGN: A total of 624 patients with presumed pulmonary TB were enrolled prospectively and categorised as smear-negative TB, smear-positive TB or no TB. All patients were tested using T-SPOT.TB. RESULTS: Both the smear-negative and smear-positive TB groups had significantly more spot-forming cells (SFCs) than the no TB group (all P < 0.001), while the smear-negative group had fewer SFCs than the smear-positive TB group (P < 0.001). The specificity of T-SPOT.TB was 60.4% (95%CI 53.4-67.1). The sensitivities of T-SPOT.TB in the smear-negative and smear-positive TB groups were respectively 81.4% (95%CI 75.7-86.0) and 93.2% (95%CI 87.6-96.4). The sensitivity in the smear-negative TB group was much lower than that in the smear-positive TB (P < 0.05). CONCLUSIONS: The sensitivity of T-SPOT.TB was lower due the paucibacillary nature of the samples, and the specificity was lower due to the high prevalence of latent tuberculous infection in the smear-negative TB patients. The T-SPOT.TB test should only be used as a supplementary test and not as a single test to rule in or rule out smear-negative TB.