Lung Diffusing Capacity for Nitric Oxide and Carbon Monoxide After Hematopoietic Stem-cell Transplantation

Study Overview
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Brief Summary
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Early after allogeneic hematopoietic stem-cell transplantation (allo-HSCT), reductions of absolute lung volume and diffusing capacity for carbon monoxide (DLCO) are frequently detected even in the absence of overt idiopathic pneumonia syndrome (IPS). It can be hypothesized that these changes might be due to an occult intersitial lung disease associated with infections, acute Graft-versus-Host Disease (aGvHD), myeloablative conditioning regimens or any combination of these. To test this hypothesis, we will simultaneously measure the lung diffusing capacity for nitric oxide (DLNO) and DLCO and estimate the changes of membrane diffusing capacity (DM) and pulmonary capillary volume (Vc) by the DLNO/DLCO ratio. As we hypothesize that GHVD should be intuitively absent amongst autologous HSCT (auto-HSCT) recipients, we will compare the changes in DLNO/DLCO ratio showed by the latter group with those of subjects undergoing allo-HSCT.

Detailed Description
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In allogeneic hematopoietic stem-cell transplantation (allo-HSCT) recipients, early reductions of absolute lung volume and diffusing capacity for carbon monoxide (DLCO) are frequently detected even in the absence of overt idiopathic pneumonia syndrome (IPS)[PMID: 22221781]. Two months after allo-HSCT, we have recently shown an increase in lung tissue density determined by quantitative CT scan [PMID: 22898044]. It can be hypothesized that these parenchymal changes might be due to an occult intersitial lung disease associated with infections, acute Graft-versus-Host Disease (aGvHD), myeloablative conditioning regimens or any combination of these [PMID: 21531955]. To test this hypothesis, we will simultaneously measure the lung diffusing capacity for nitric oxide (DLNO) and DLCO. Assuming, for clinical purposes, that the reaction rate of NO with blood hemoglobin is infinite so that DLNO = DMNO = DMCO*alpha (alpha = NO/CO diffusivity ratio), as to partition the effect of HSCT on membrane diffusing capacity (DM) and pulmonary capillary volume (Vc) we will use the DLNO/DLCO ratio [PMID:16478855]. As we hypothesize that GHVD should be intuitively absent amongst autologous HSCT (auto-HSCT) recipients, we will compare the changes in DLNO/DLCO ratio showed by the latter group with those of subjects undergoing allo-HSCT.

Official Title
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Changes in Lung Diffusing Capacity for Nitric Oxide and Carbon Monoxide After Allogeneic Versus Autologous Hematopoietic Stem-cell Transplantation

Conditions
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Lung Disease

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: baseline spirometry, lung volumes, and DLCO of the subjects included in the analysis must be within the predicted normal range all patients must be in stable clinical conditions at the time of study Exclusion Criteria: a history of bronchial asthma, chronic obstructive pulmonary disease, or other significant respiratory disease

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in DLNO/DLCO ratio after allo- versus autologous HSCT |  | Before and 2-6 months after HSCT | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in lung tissue density after allo- versus autologous HSCT |  | Before and 2-6 months after HSCT | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Allogeneic and autologous, hematopoietic stem-cell transplantation, Lung diffusing capacity, for nitric oxide, carbon monoxide, Lung tissue density, microvascular damage