Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Kevin O. Leslie is active.

Publication


Featured researches published by Kevin O. Leslie.


European Respiratory Journal | 2015

An official European Respiratory Society/American Thoracic Society research statement: interstitial pneumonia with autoimmune features

Aryeh Fischer; Katerina M. Antoniou; Kevin K. Brown; Jacques Cadranel; Tamera J. Corte; Roland M. du Bois; Joyce S. Lee; Kevin O. Leslie; David A. Lynch; Eric L. Matteson; Marta Mosca; Imre Noth; Luca Richeldi; Mary E. Strek; Jeffrey J. Swigris; Athol U. Wells; Sterling G. West; Harold R. Collard; Vincent Cottin

Many patients with an idiopathic interstitial pneumonia (IIP) have clinical features that suggest an underlying autoimmune process but do not meet established criteria for a connective tissue disease (CTD). Researchers have proposed differing criteria and terms to describe these patients, and lack of consensus over nomenclature and classification limits the ability to conduct prospective studies of a uniform cohort. The “European Respiratory Society/American Thoracic Society Task Force on Undifferentiated Forms of Connective Tissue Disease-associated Interstitial Lung Disease” was formed to create consensus regarding the nomenclature and classification criteria for patients with IIP and features of autoimmunity. The task force proposes the term “interstitial pneumonia with autoimmune features” (IPAF) and offers classification criteria organised around the presence of a combination of features from three domains: a clinical domain consisting of specific extra-thoracic features, a serologic domain consisting of specific autoantibodies, and a morphologic domain consisting of specific chest imaging, histopathologic or pulmonary physiologic features. A designation of IPAF should be used to identify individuals with IIP and features suggestive of, but not definitive for, a CTD. With IPAF, a sound platform has been provided from which to launch the requisite future research investigations of a more uniform cohort. ERS/ATS task force provides nomenclature and classification criteria for patients with IIP and autoimmune features http://ow.ly/O7qao


The American Journal of Surgical Pathology | 2010

Optimal Immunohistochemical Markers For Distinguishing Lung Adenocarcinomas From Squamous Cell Carcinomas in Small Tumor Samples

Jefferson Terry; Samuel Leung; Janessa Laskin; Kevin O. Leslie; Allen M. Gown; Diana N. Ionescu

The histologic subtype of non-small cell lung carcinoma is important in selecting appropriate chemotherapy for patients with advanced disease. As many of these patients are not operative candidates, they are treated medically after biopsy for diagnosis. Inherent limitations of small biopsy samples can make distinguishing poorly differentiated lung adenocarcinoma (ADC) from squamous cell carcinoma (SCC) difficult. The value of histochemical and immunohistochemical markers to help separate poorly differentiated ADC from SCC in resection specimens is well established; however, the optimal use of markers in small tissue samples has only recently been examined and the correlation of marker expression in small tissue samples with histologic subtype determined on resection specimens has not been well documented. We address this issue by examining the expression of 9 markers (p63, TTF1, CK5/6, CK7, 34&bgr;E12, Napsin A, mucicarmine, NTRK1, and NTRK2) on 200 cases of ADC and 225 cases of SCC in tissue microarray format to mimic small tissue specimens. The single best marker to separate ADC from SCC is p63 (for SCC: sensitivity 84%, specificity 85%). Logistic regression analysis identifies p63, TTF1, CK5/6, CK7, Napsin A, and mucicarmine as the optimal panel to separate ADC from SCC. Reduction of the panel to p63, TTF1, CK5/6, and CK7 is marginally less effective but may be the best compromise when tissue is limited. We present an algorithm for the stepwise application of p63, TTF1, CK5/6, CK7, Napsin A, and mucicarmine in situations in which separation of ADC from SCC in small specimens cannot be accomplished by morphology alone.


American Journal of Clinical Pathology | 2001

Diffuse Pulmonary Disease Caused by Nontuberculous Mycobacteria in Immunocompetent People (Hot Tub Lung)

Andras Khoor; Kevin O. Leslie; Henry D. Tazelaar; Richard A. Helmers; Thomas V. Colby

The clinicopathologic spectrum of infections due to nontuberculous mycobacteria (NTM) includes cavitary disease, opportunistic infection, and nodular disease associated with bronchiectasis. We report a less well-described manifestation of NTM infection: 10 immunocompetent patients without preexisting bronchiectasis had radiographic evidence of diffuse infiltrative lung disease. The most common symptoms were dyspnea, cough, hypoxia, and fever. All 10 patients had used a hot tub. Histologic examination revealed exuberant nonnecrotizing, frequently bronchiolocentric, granulomatous inflammation in all cases. In 1 case, necrotizing granulomas were also noted. The inflammation often was associated with patchy chronic interstitial pneumonia and organization. Cultures revealed NTM in all cases (Mycobacterium avium complex in all but 1 case), but staining for acid-fast bacilli was positive in only 1 case. Four patients received corticosteroids alone for presumed hypersensitivity pneumonia, 4 were treated with antimycobacterial therapy, and 2 received both. All patients demonstrated significant improvement at the time of follow-up. These findings suggest that disease due to NTM may manifest as diffuse infiltrates in immunocompetent adults and that hot tub use may be an important risk factor for this disease pattern.


Circulation | 1996

Skeletal Muscle and Cardiovascular Adaptations to Exercise Conditioning in Older Coronary Patients

Philip A. Ades; Mary L. Waldmann; William L. Meyer; Kenneth A. Brown; Eric T. Poehlman; William W. Pendlebury; Kevin O. Leslie; Peter R. Gray; Richard Lew; Martin M. LeWinter

BACKGROUND Older coronary patients suffer from a low functional capacity and high rates of disability. Supervised exercise programs improve aerobic capacity in middle-aged coronary patients by improving both cardiac output and peripheral extraction of oxygen. Physiological adaptations to aerobic conditioning, however, have not been well studied in older coronary patients. METHODS AND RESULTS The effect of a 3-month and a 1-year program of intense aerobic exercise was studied in 60 older coronary patients (mean age, 68 +/- 5 years) beginning 8 +/- 5 weeks after myocardial infarction or coronary bypass surgery. Outcome measures included peak aerobic capacity, cardiac output, arterio-venous oxygen difference, hyperemic calf blood flow, and skeletal muscle fiber morphometry, oxidative enzyme activity, and capillarity. Training results were compared with a sedentary, age- and diagnosis-matched control group (n = 10). Peak aerobic capacity increased in the intervention group at 3 months and at 1 year by 16% and 20%, respectively (both P < .01). Peak exercise cardiac output, hyperemic calf blood flow, and vascular conductance were unaffected by the conditioning protocol. At 3 and 12 months, arteriovenous oxygen difference at peak exercise was increased in the exercise group but not in control subjects. Histochemical analysis of skeletal muscle documented a 34% increase in capillary density and a 23% increase in succinate dehydrogenase activity after 3 months of conditioning (both P < .02). At 12 months, individual fiber area increased by 29% compared with baseline (P < .01). CONCLUSIONS Older coronary patients successfully improve peak aerobic capacity after 3 and 12 months of supervised aerobic conditioning compared with control subjects. The mechanism of the increase in peak aerobic capacity is associated almost exclusively with peripheral skeletal muscle adaptations, with no discernible improvements in cardiac output or calf blood flow.


Respiration | 2008

Serial Development of Pulmonary Hypertension in Patients with Idiopathic Pulmonary Fibrosis

Steven D. Nathan; Oksana A. Shlobin; Shahzad Ahmad; Jim Koch; Scott D. Barnett; Niv Ad; Nelson Burton; Kevin O. Leslie

Background: Idiopathic pulmonary fibrosis (IPF) is a disease with very high mortality. Objective: We sought to characterize serial changes in pulmonary artery pressures (PAP) in patients with advanced IPF who survive to transplant. Methods: Retrospective analysis of IPF patients comparing mean PAP at the time of initial evaluation for transplan- tation (mPAPbaseline) with mPAP at the time of transplant (mPAPfollow-up). The measurements were correlated with New York Heart Association (NYHA) functional class and oxygen requirements. Results: The final cohort consisted of 44 patients with serial right heart catheterization data. The mean mPAPbaseline and mPAPfollow-up were 22.5 and 32.7 mm Hg, respectively. 38.6% (17/44) of the patients had pulmonary hypertension (PH) at baseline. The majority of the non-PH patients developed PH during the serial time interval with a subsequent incidence of 77.8%. At the time of transplant, 86.4% of the patients had PH. There was a significant association between transplant NYHA class, severity of PH and oxygen requirements. Transplant NYHA class IV patients had a higher rate of mPAP change. The severity of PH at the time of transplant did not affect transplant outcomes. Conclusion: PH is common and progressive in patients with advanced IPF who are transplant candidates. Serial change and severity of PAP elevations have a significant association with oxygen requirements and functional status, but not transplant outcomes. Whether or not progressive PH has a significant impact on outcomes without transplantation requires further study.


The Lancet Respiratory Medicine | 2014

Diagnosis of idiopathic pulmonary fibrosis with high-resolution CT in patients with little or no radiological evidence of honeycombing: secondary analysis of a randomised, controlled trial

Ganesh Raghu; David A. Lynch; J. David Godwin; Richard Webb; Thomas V. Colby; Kevin O. Leslie; Juergen Behr; Kevin K. Brown; Jim J. Egan; Kevin R. Flaherty; Fernando J. Martinez; Athol U. Wells; Lixin Shao; Huafeng Zhou; Patricia S Pedersen; Rohit Sood; A. Bruce Montgomery; Thomas G. O'Riordan

BACKGROUND Present guidelines for the diagnosis of idiopathic pulmonary fibrosis require histological confirmation of surgical lung biopsy samples when high-resolution CT images are not definitive for usual interstitial pneumonia. We aimed to assess the predictive value of high-resolution CT in a cohort of patients with suspected idiopathic pulmonary fibrosis from a previous randomised trial. METHODS ARTEMIS-IPF was a randomised, double-blind, placebo-controlled, multicentre, phase 3 trial of ambrisentan for adults aged 40-80 years with well-defined idiopathic pulmonary fibrosis and 5% or less honeycombing on high-resolution CT. In December, 2010, an interim analysis showed lack of efficacy and the trial was stopped. In the present follow-on analysis, we assessed patients who were screened for ARTEMIS-IPF who underwent high-resolution CT as part of screening and surgical lung biopsy as part of standard clinical care. A radiologist and a pathologist from a central panel independently assessed anonymised CT scans and biopsy samples. We calculated the positive and negative predictive value of high-resolution CT (classified as usual interstitial pneumonia, possible usual interstitial pneumonia, and inconsistent with usual interstitial pneumonia) for confirmation of histological patterns of usual interstitial pneumonia. This study is registered with ClinicalTrials.gov, number NCT00768300. FINDINGS 315 (29%) of 1087 consecutively screened patients in ARTEMIS-IPF had both high-resolution CT and surgical lung biopsy samples. 108 of 111 patients who met high-resolution CT criteria for usual interstitial pneumonia had histologically confirmed usual interstitial pneumonia (positive predictive value 97·3%, 95% CI 92·3-99·4), as did 79 of 84 patients who met high-resolution CT criteria for possible usual interstitial pneumonia (94·0%, 86·7-98·0). 22 of 120 patients had an inconsistent high-resolution CT pattern for usual interstitial pneumonia that was histologically confirmed as not or possible usual interstitial pneumonia (negative predictive value 18·3%, 95% CI 11·9-26·4). INTERPRETATION In the appropriate clinical setting, for patients with possible usual interstitial pneumonia pattern on high resolution CT, surgical lung biopsy sampling might not be necessary to reach a diagnosis of idiopathic pulmonary fibrosis if high-resolution CT scans are assessed by experts at regional sites familiar with patterns of usual interstitial pneumonia and management of idiopathic interstitial pneumonia. FUNDING Gilead Sciences.


The American Journal of Surgical Pathology | 1998

Micronodular pneumocyte hyperplasia.

Trudie E. Muir; Kevin O. Leslie; Helmut Popper; Masanori Kitaichi; Eric Gagné; Jessica K. Emelin; Harry V. Vinters; Thomas V. Colby

Tuberous sclerosis complex (TSC) is an autosomal-dominant disorder characterized by mental retardation, seizures, and central nervous system and visceral hamartomas. Pulmonary involvement manifesting as lymphangioleiomyomatosis (LAM) occurs in 1% of patients (all women) with TSC. Micronodular pneumocyte hyperplasia also has been described as a rare pulmonary manifestation of TSC. We report 14 patients with micronodular pneumocyte hyperplasia (MNPH). The patients ranged in age from 23 to 57 years (mean 37.5). There were 12 women and 2 men. Nine of the patients (one man and eight women) had documented clinical manifestations of TSC: seven with LAM, two without LAM (including one man). Of the five patients who did not have TSC, three had LAM and two did not (including one man). Histologically, all 14 cases demonstrated multiple well-demarcated nodules usually measuring up to 8 mm in size, but most were 1-3 mm. The nodules were produced by a proliferation of enlarged cytologically benign type II pneumocytes, with an associated increase in alveolar macrophages and interstitial reticulin. Immunoperoxidase studies showed the type II pneumocytes within lesions to be reactive with antibodies to cytokeratin (four of four), epithelial membrane antigen (EMA) (five of five), and surfactant apoprotein B (8 of 10). HMB-45 was negative in the MNPH lesions in all nine cases studied. Follow-up was available in 9 of 10 living patients and ranged from 1 to 14 years (mean 6 years). Nine patients are alive; six are clinically stable and three have repeated pneumothoraces related to LAM. Four patients have died. None of the deaths were attributable to MNPH. MNPH appears to be a hamartomatous proliferation occurring most frequently in patients with tuberous sclerosis, is separable from and not a manifestation of LAM, has been observed to occur in men, and, like other hamartomas of tuberous sclerosis, does not appear to possess malignant potential.


Chest | 2014

EIF2AK4 Mutations in Pulmonary Capillary Hemangiomatosis

D. Hunter Best; Kelli Sumner; Eric D. Austin; Wendy K. Chung; Lynette M. Brown; Alain C. Borczuk; Erika B. Rosenzweig; Pinar Bayrak-Toydemir; Rong Mao; Barbara C. Cahill; Henry D. Tazelaar; Kevin O. Leslie; Anna R. Hemnes; Ivan M. Robbins; C. Gregory Elliott

BACKGROUND Pulmonary capillary hemangiomatosis (PCH) is a rare disease of capillary proliferation of unknown cause and with a high mortality. Families with multiple affected individuals with PCH suggest a heritable cause although the genetic etiology remains unknown. METHODS We used exome sequencing to identify a candidate gene for PCH in a family with two affected brothers. We then screened 11 unrelated patients with familial (n = 1) or sporadic (n = 10) PCH for mutations. RESULTS Using exome sequencing, we identified compound mutations in eukaryotic translation initiation factor 2 α kinase 4 (EIF2AK4) (formerly known as GCN2) in both affected brothers. Both parents and an unaffected sister were heterozygous carriers. In addition, we identified two EIF2AK4 mutations in each of two of 10 unrelated individuals with sporadic PCH. EIF2AK4 belongs to a family of kinases that regulate angiogenesis in response to cellular stress. CONCLUSIONS Mutations in EIF2AK4 are likely to cause autosomal-recessive PCH in familial and some nonfamilial cases.


The American Journal of Surgical Pathology | 2002

Endometrial stromal sarcoma metastatic to the lung: a detailed analysis of 16 patients.

Marie Christine Aubry; Jeffrey L. Myers; Thomas V. Colby; Kevin O. Leslie; Henry D. Tazelaar

Pulmonary metastases of endometrial stromal sarcoma (ESS) are uncommon and can pose diagnostic problems. We reviewed lung specimens from 16 patients with metastatic ESS. Patients were 31–77 years of age at the time of lung biopsy. Uterine ESSs were diagnosed an average of 9.8 years before lung biopsy in 11 patients. Uterine ESSs were originally called smooth muscle tumors in three additional patients. Thirteen patients were evaluated for new pulmonary nodules, seven of whom were asymptomatic. Nodules were multiple in 14 and solitary in four, ranging from 1.0 to 8.0 cm in greatest dimension. One patient died of metastatic disease; 14 were alive and seven of these were without disease (mean follow-up 4.1 years). Diagnostic considerations in 12 consultation cases included ESS, sclerosing hemangioma, carcinoid tumor, lymphangioleiomyomatosis, endometriosis, hemangiopericytoma, and lymphoma. Tumors were well circumscribed and usually solid, composed of plump spindle cells arranged in short fascicles. Two tumors were predominantly cystic. Sex cord-like stromal differentiation was identified in three. Neoplastic cells stained for vimentin (93%), estrogen and progesterone receptor (100%), smooth muscle actin (57%), desmin (50%), and keratin (46%). Metastatic ESS should be included in the differential diagnosis of nonepithelial neoplasms in women.


Respiration | 2006

Pulmonary fibrosis in hermansky-pudlak syndrome : A case report and review

Diane M. Pierson; Diana N. Ionescu; Gefei Qing; Abdullah M. Yonan; Kent Parkinson; Thomas C. Colby; Kevin O. Leslie

Hermansky-Pudlak syndrome (HPS) is a rare heterogeneously inherited autosomal recessive group of disorders presenting with oculocutaneous albinism, bleeding diathesis and pulmonary disease. HPS is thought to occur as a consequence of disturbed formation or trafficking of intracellular vesicles, most importantly, melanosomes, platelet dense granules and lysosomes. The latter finding, in particular, contributes much to the morbidity associated with the disease, as ceroid lipofuscin deposits in lysosomes affect many organ systems. This is especially problematic in the lungs where it is often associated with pulmonary fibrosis and premature death. Currently, there are 7 known HPS genes in humans. In the mouse, at least 16 known HPS genes produce HPS-mutant phenotypes. The HPS gene mutation is considered to be one of the most prevalent single-gene disorders in northwest Puerto Rico, home to the largest cohort of known patients. In HPS, interventions addressing the bleeding diathesis and pulmonary fibrosis are often disappointingly ineffectual. Pirfenidone, a novel compound with documented anti-inflammatory, antioxidant and antifibrotic effects, appears to hold promise in delaying or preventing fibrosis. To date, there has been one successful lung transplant performed on a patient with HPS. We present a patient with HPS and review the current literature on our understanding of this rare disorder.

Collaboration


Dive into the Kevin O. Leslie's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Diana N. Ionescu

University of British Columbia

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge