Evaluation of Sensitivity of Multiplex PCR for Detection of Mycobacterium tuberculosis and Pneumocystis jirovecii in Clinical Samples ▿

A multiplex PCR assay for the simultaneous detection of Mycobacterium tuberculosis and Pneumocystis jirovecii was developed using IS6110-based detection for M. tuberculosis and mitochondrial large-subunit (mtLSU) rRNA gene detection for P. jirovecii. Ninety-five pulmonary blinded samples were examined using the developed multiplex PCR assay, and the results were compared with those obtained by the single nested PCRs targeting IS6110 for M. tuberculosis and mtLSU rRNA for P. jirovecii. Of the 95 pulmonary samples tested, the multiplex nested PCR developed here could detect 36 cases of M. tuberculosis infection, 35 cases of P. jirovecii infection, and 17 cases of M. tuberculosis and P. jirovecii coinfections. The sensitivities of the multiplex nested PCR in detecting M. tuberculosis and P. jirovecii were 92.1% and 81.4%, respectively, whereas the specificities in detecting M. tuberculosis and P. jirovecii were 98.2% and 100%, respectively

Dynamic Measurement of Hemodynamic Parameters and Cardiac Preload in Adults with Dengue: A Prospective Observational Study.

Few previous studies have monitored hemodynamic parameters to determine the physiological process of dengue or examined inferior vena cava (IVC) parameters to assess cardiac preload during the clinical phase of dengue. From January 2013 to July 2015, we prospectively studied 162 hospitalized adults with confirmed dengue viral infection using non-invasive cardiac output monitoring and bedside ultrasonography to determine changes in hemodynamic and IVC parameters and identify the types of circulatory shock that occur in patients with dengue. Of 162 patients with dengue, 17 (10.5%) experienced dengue shock and 145 (89.5%) did not. In patients with shock, the mean arterial pressure was significantly lower on day 6 after fever onset (P = 0.045) and the pulse pressure was significantly lower between days 4 and 7 (P<0.05). The stroke volume index and cardiac index were significantly decreased between days 4 and 15 and between days 5 and 8 after fever onset (P<0.05), respectively. A significant proportion of patients with dengue shock had an IVC diameter <1.5 cm and IVC collapsibility index >50% between days 4 and 5 (P<0.05). Hypovolemic shock was observed in 9 (52.9%) patients and cardiogenic shock in 8 (47.1%), with a median (interquartile range) time to shock onset of 6.0 (5.0-6.5) days after fever onset, which was the median day of defervescence. Intravascular hypovolemia occurred before defervescence, whereas myocardial dysfunction occurred on the day of defervescence until 2 weeks after fever onset. Hypovolemic shock and cardiogenic shock each occurred in approximately half of the patients with dengue shock. Therefore, dynamic measures to estimate changes in hemodynamic parameters and preload should be monitored to ensure adequate fluid therapy among patients with dengue, particularly patients with dengue shock

Serum Procalcitonin and Peripheral Venous Lactate for Predicting Dengue Shock and/or Organ Failure: A Prospective Observational Study

<div><p>Background</p><p>Currently, there are no biomarkers that can predict the incidence of dengue shock and/or organ failure, although the early identification of risk factors is important in determining appropriate management to reduce mortality. Therefore, we sought to determine the factors associated with dengue shock and/or organ failure and to evaluate the prognostic value of serum procalcitonin (PCT) and peripheral venous lactate (PVL) levels as biomarkers of dengue shock and/or organ failure.</p><p>Methodology/Principal Findings</p><p>A prospective observational study was conducted among adults hospitalized for confirmed viral dengue infection at the Hospital for Tropical Diseases in Bangkok, Thailand between October 2013 and July 2015. Data, including baseline characteristics, clinical parameters, laboratory findings, serum PCT and PVL levels, management, and outcomes, were recorded on pre-defined case report forms. Of 160 patients with dengue, 128 (80.0%) patients had dengue without shock or organ failure, whereas 32 (20.0%) patients developed dengue with shock and/or organ failure. Using a stepwise multivariate logistic regression analysis, PCT ≥0.7 ng/mL (odds ratio [OR]: 4.80; 95% confidence interval [CI]: 1.60–14.45; <i>p</i> = 0.005) and PVL ≥2.5 mmol/L (OR: 27.99, 95% CI: 8.47–92.53; <i>p</i> <0.001) were independently associated with dengue shock and/or organ failure. A combination of PCT ≥0.7 ng/mL and PVL ≥2.5 mmol/L provided good prognostic value for predicting dengue shock and/or organ failure, with an area under the receiver operating characteristics curve of 0.83 (95% CI: 0.74–0.92), a sensitivity of 81.2% (95% CI: 63.6–92.8%), and a specificity of 84.4% (95% CI: 76.9–90.2%). Dengue shock patients with non-clearance of PCT and PVL expired during hospitalization.</p><p>Conclusions/Significance</p><p>PCT ≥0.7 ng/mL and PVL ≥2.5 mmol/L were independently associated with dengue shock and/or organ failure. The combination of PCT and PVL levels could be used as prognostic biomarkers for the prediction of dengue shock and/or organ failure.</p></div

Laboratory parameters categorized based on reference ranges among 160 hospitalized adults with dengue.

<p>Laboratory parameters categorized based on reference ranges among 160 hospitalized adults with dengue.</p

Flow diagram showing the recruitment of study patients.

<p>ELISA, enzyme-linked immunosorbent assay; RT-PCR, reverse-transcriptase polymerase chain reaction.</p

Daily changes in serum procalcitonin and peripheral venous lactate during hospitalization.

<p>(A) Changes in average serum procalcitonin (ng/mL) levels among patients with and without dengue shock and/or organ failure by survival status. (B) Changes in peripheral venous lactate (mmol/L) levels among patients with and without dengue shock and/or organ failure by survival status. Data are presented as box and whisker plots with median (horizontal line), interquartile range (box), and maximum value within 1.5 of interquartile range (whiskers).</p

Serum procalcitonin and peripheral venous lactate at admission in dengue patients.

<p>(A) Serum procalcitonin levels among patients with and without dengue shock and/or organ failure. (B) Peripheral venous lactate levels among patients with and without dengue shock and/or organ failure. Data are presented as box and whisker plots with median (horizontal line), interquartile range (box), maximum value within 1.5 of interquartile range (whiskers), outliers (circles), and extreme outliers (asterisks).</p

Multivariate logistic regression analysis for the prediction of dengue shock and/or organ failure using laboratory parameters.

<p>Multivariate logistic regression analysis for the prediction of dengue shock and/or organ failure using laboratory parameters.</p

Baseline characteristics and clinical parameters at admission among 160 hospitalized adults with dengue.

<p>Baseline characteristics and clinical parameters at admission among 160 hospitalized adults with dengue.</p

Univariate analysis for the prediction of dengue shock and/or organ failure using clinical and laboratory parameters.

<p>Univariate analysis for the prediction of dengue shock and/or organ failure using clinical and laboratory parameters.</p