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The ratio of FVC to slow inspiratory vital capacity (SVC) has been reported to reflect small airways obstruction, but its validity as such is still unclear. The aim of this study was to assess the applicability of the FVC/SVC ratio as a marker of small airways function in patients with bronchiolitis obliterans syndrome (BOS) after lung transplantation (LTX), which is a disorder in which predominantly small airways obstruction causes progressive airflow limitation.The FVC/SVC ratio was analyzed both cross-sectionally and longitudinally in 39 patients (26 men) with BOS after bilateral LTX (median age, 47 years; interquartile range [IQR], 35 to 54 years), and 36 bilateral lung transplant recipients without BOS (14 men; median age, 46 years; IQR, 41 to 53 years).The FVC/SVC ratio decreased significantly during follow-up in patients with BOS stages 1 and 2, by 2.2% and 4.4%, respectively, from baseline (p0.001). This decrease was not significantly associated with the decrease in FEV(1). The FVC/SVC ratio increased, though not significantly, in the group in which BOS did not develop by 1.1%, which is a significant difference from the average fall of 4.4% in the group in which BOS developed.Significant, yet small decreases in FVC/SVC ratio occur in patients in whom BOS develops, independent from changes in FEV(1). At a group level, FVC/SVC ratio is able to detect small airways changes. These results merit prospective studies to determine the sensitivity of FVC/SVC ratio to quantifying small airways dysfunction at an individual level and in other airway diseases.

Background: Presently the semiquantitative pp65 cytomegalovirus (CMV) antigenemia test on white blood cells is often used for monitoring transplant patients for the appearance of active CMV infections. However, the need for immediate processing of the specimens and the lack of interlaboratory standardization of the test may sometimes be a disadvantage. Objective: The aim of this study was to investigate the value of the recently developed second version of the Murex Hybrid Capture(TM) (MHC) CMV-DNA assay (v 2.0) in comparison with the CMV-pp65 test. The MHC CMV-DNA assay is a quantitative solution hybridization antibody capture assay, using alkaline phosphatase conjugated antibodies and a chemiluminescent substrate. Study design: 248 EDTA blood samples from 33 renal transplant patients and 32 samples from 22 other immunocompromised patients were tested by both the MHC CMV-DNA assay and the CMV-pp65 test. Results: The qualitative (+ or -) results of both tests showed an overall concordance of 81.4%,. Calculations on the basis of discordancy analyses showed that the sensitivity, the specificity, and the positive and negative predictive values were 87.7 98.3, 98.6, 85.2% for the MHC CMV-DNA assay and 76.6, 100, 100, 75.5% for the CMV-pp65 test. Comparison of the quantitative results of both tests systems showed a correlation coefficient of 0.837. In addition, retesting of 50 samples with the MHC-CMV-DNA assay showed an excellent reproducibility with a correlation coefficient of 0.992. All patients which were tested regularly (at least five samples) became either positive with both tests or with none of them. Neither test system detected CMV significantly earlier than the other one. Both tests became strongly positive in all transplant patients with symptomatic CMV infections, and both tests showed a rapid decline of CMV during subsequent antiviral treatment. Conclusion: The quantitative Murex Hybrid Capture(TM) CMV-DNA assay (v 2.0) may become a valuable additional tool in CMV diagnosis. Further studies will be needed to support this preliminary judgement. (C) 1999 Elsevier Science B.V. All rights reserved.