A prospective study to evaluate a diagnostic algorithm for the use of fluid lymphocyte subset analysis in undiagnosed unilateral pleural effusions

&lt;b&gt;&lt;i&gt;Background:&lt;/i&gt;&lt;/b&gt; Haematological malignancy is an important cause of pleural effusion. Pleural effusions secondary to haematological malignancy are usually lymphocyte predominant. However, several other conditions such as carcinoma, tuberculosis, and chronic heart failure also cause lymphocytic effusions. Lymphocyte subset (LS) analysis may be a useful test to identify haematological malignancy in patients with lymphocytic effusions. However, research into their utility in pleural effusion diagnostic algorithms has not yet been published. &lt;b&gt;&lt;i&gt;Objectives:&lt;/i&gt;&lt;/b&gt; We aimed to determine the clinical utility of pleural fluid LS analysis and whether it can be applied to a diagnostic algorithm to identify effusions secondary to haematological malignancy. The secondary aim was to evaluate the diagnostic value of pleural fluid differential cell count. &lt;b&gt;&lt;i&gt;Methods:&lt;/i&gt;&lt;/b&gt; Consecutive consenting patients presenting to our pleural service between 2008 and 2013 underwent thoracentesis and differential cell count analysis. We proposed an algorithm which selected patients with lymphocytic effusions (&gt;50%) to have further fluid sent for LS analysis. Two independent consultants agreed on the cause of the original effusion after a 12-month follow-up period. &lt;b&gt;&lt;i&gt;Results:&lt;/i&gt;&lt;/b&gt; A total of 60 patients had samples sent for LS analysis. LS analysis had an 80% sensitivity (8/10) and a 100% specificity for the diagnosis of haematological malignancy. The positive and negative predictive values were 100 and 96.1%, respectively. Overall 344 differential cell counts were analysed; 16% of pleural effusions with a malignant aetiology were neutrophilic or eosinophilic at presentation. A higher neutrophil and eosinophil count was associated with benign diagnoses, whereas a higher lymphocyte count was associated with malignant diagnoses. &lt;b&gt;&lt;i&gt;Conclusions:&lt;/i&gt;&lt;/b&gt; LS analysis may identify haematological malignancy in a specific cohort of patients with undiagnosed pleural effusions. A pleural fluid differential cell count provides useful additional information to streamline patient pathway decisions.</jats:p

Native T1 mapping in the diagnosis of cardiac allograft rejection: A prospective histologically validated study

OBJECTIVES: This study aimed to determine the role of T1 mapping in identifying cardiac allograft rejection. BACKGROUND: Endomyocardial biopsy (EMBx), the current gold standard to diagnose cardiac allograft rejection, is associated with potentially serious complications. Cardiac magnetic resonance (CMR)-based T1 mapping detects interstitial edema and fibrosis, which are important markers of acute and chronic rejection. Therefore, T1 mapping can potentially diagnose cardiac allograft rejection noninvasively. METHODS: Patients underwent CMR within 24 h of EMBx. T1 maps were acquired at 1.5-T. EMBx-determined rejection was graded according to International Society of Heart and Lung Transplant (ISHLT) criteria. RESULTS: Of 112 biopsies with simultaneous CMR, 60 were classified as group 0 (ISHLT grade 0), 35 as group 1 (ISHLT grade 1R), and 17 as group 2 (2R, 3R, clinically diagnosed rejection, antibody-mediated rejection). Native T1 values in patients with grade 0 biopsies and left ventricular ejection fraction >60% (983 ± 42 ms; 95% confidence interval: 972 to 994) were comparable to values in nontransplant healthy control subjects (974 ± 45 ms; 95% confidence interval: 962 to 987). T1 values were significantly higher in group 2 (1,066 ± 78 ms) versus group 0 (984 ± 42 ms; p = 0.0001) and versus group 1 (1,001 ± 54 ms; p = 0.001). After excluding patients with an estimated glomerular filtration rate <50 ml/min/m2, there was a moderate correlation of log-transformed native T1 with high-sensitivity troponin T (r = 0.54, p < 0.0001) and pro-B-type natriuretic peptide (r = 0.67, p < 0.0001). Using a T1 cutoff value of 1,029 ms, the sensitivity, specificity, and negative predictive value were 93%, 79%, and 99%, respectively. CONCLUSIONS: Myocardial tissue characterization with T1 mapping displays excellent negative predictive capacity for the noninvasive detection of cardiac allograft rejection and holds promise to reduce substantially the EMBx requirement in cardiac transplant rejection surveillance

Reference values for healthy human myocardium using a T1 mapping methodology: results from the International T1 Multicenter cardiovascular magnetic resonance study

BACKGROUND:T1 mapping is a robust and highly reproducible application to quantify myocardial relaxation of longitudinal magnetisation. Available T1 mapping methods are presently site and vendor specific, with variable accuracy and precision of T1 values between the systems and sequences. We assessed the transferability of a T1 mapping method and determined the reference values of healthy human myocardium in a multicenter setting.METHODS:Healthy subjects (n = 102; mean age 41 years (range 17-83), male, n = 53 (52%)), with no previous medical history, and normotensive low risk subjects (n=113) referred for clinical cardiovascular magnetic resonance (CMR) were examined. Further inclusion criteria for all were absence of regular medication and subsequently normal findings of routine CMR. All subjects underwent T1 mapping using a uniform imaging set-up (modified Look- Locker inversion recovery, MOLLI, using scheme 3(3)3(3)5)) on 1.5 Tesla (T) and 3 T Philips scanners. Native T1-maps were acquired in a single midventricular short axis slice and repeated 20 minutes following gadobutrol. Reference values were obtained for native T1 and gadolinium-based partition coefficients, lambda and extracellular volume fraction (ECV) in a core lab using standardized postprocessing.RESULTS:In healthy controls, mean native T1 values were 950 +/- 21 msec at 1.5 T and 1052 +/- 23 at 3 T. lambda and ECV values were 0.44 +/- 0.06 and 0.25 +/- 0.04 at 1.5 T, and 0.44 +/- 0.07 and 0.26 +/- 0.04 at 3 T, respectively. There were no significant differences between healthy controls and low risk subjects in routine CMR parameters and T1 values. The entire cohort showed no correlation between age, gender and native T1. Cross-center comparisons of mean values showed no significant difference for any of the T1 indices at any field strength. There were considerable regional differences in segmental T1 values. lambda and ECV were found to be dose dependent. There was excellent inter- and intraobserver reproducibility for measurement of native septal T1.CONCLUSION:We show transferability for a unifying T1 mapping methodology in a multicenter setting. We provide reference ranges for T1 values in healthy human myocardium, which can be applied across participating sites