Asthma-COPD overlap syndrome (ACOS) has been described and acknowledged as a distinct clinical entity; however, its characteristics in daily clinical practice are largely unknown. The aim of this study was to identify the prevalence of ACOS in the real-life population, its pattern of comorbidities, and its impact on hospitalization risk.

Asthma is characterized by chronic airway inflammation. Fractional exhaled nitric oxide (Feno) has emerged as a marker of T-helper cell type 2-mediated allergic airway inflammation. Recent studies suggest a role for Feno testing as a point-of-care tool in the management of patients with asthma. This Topics in Practice Management article reviews current coverage and reimbursement issues related to Feno testing and provides an overview of pertinent recent studies.

COPD is a significant public health challenge, notably set to become the third leading cause of death and fifth leading cause of chronic disability worldwide by the next decade. Skeletal muscle impairment is now recognized as a disabling, extrapulmonary consequence of COPD that is associated with reduced quality of life and premature mortality. Because COPD typically manifests in older individuals, these clinical features may overlie normal age-associated declines in muscle function and performance. Although physical inactivity, oxidative stress, inflammation, hypoxia, malnutrition, and medications all likely contribute to this comorbidity, a better understanding of the underlying mechanism is needed to develop effective therapies. Mitochondrial alterations have been described; these alterations include reductions in density and oxidative enzyme activity, increased mitochondrial reactive oxygen species production, and induction of muscle proteolysis including autophagy. This review focuses on the perspective that mitochondrial alterations contribute to impaired locomotor muscle performance in patients with COPD by reducing oxidative capacity and thus endurance, as well as by triggering proteolysis and thus contributing to atrophy and weakness. We discuss how the potential underlying mechanisms converge on mitochondria by targeting the peroxisome proliferator-activated receptor γ-coactivator-1α signaling pathway (thereby reducing mitochondrial biogenesis and muscle oxidative capacity and potentially increasing fiber atrophy) and how taking advantage of normal muscle plasticity and mitochondrial biogenesis may reverse this pathophysiology. We propose recent therapeutic strategies aimed at increasing peroxisome proliferator-activated receptor γ-coactivator-1α levels, such as endurance training and exercise mimetic drugs, with the strong rationale for increasing mitochondrial biogenesis and function and thus improving the muscle phenotype in COPD.

Prior studies suggested an association between bisphosphonates and atrial fibrillation/flutter (AF) in women. This relationship in men, including those with sleep-disordered breathing (SDB), remains unclear. This study evaluated the relationship between bisphosphonate use and prevalent (nocturnal) and incident (clinically relevant) AF in a population of community-dwelling older men.

A 26-year-old white woman diagnosed with systemic lupus erythematosus (SLE) presented with left shoulder pain and a three-pillow orthopnea. Lupus was diagnosed at age 21 years when she developed arthritis, and she has been maintained on prednisone (2.5 mg) and mycophenolate (500 mg bid). In the course of evaluating her new symptoms, imaging revealed a small left pleural effusion with exudative characteristics on a diagnostic thoracentesis, but there was no evidence of infection. Her immunosuppression treatment was increased to 1,000 mg bid of mycophenolate and 20 mg of prednisone. Three months later, she presented to our clinic with worsening six-pillow orthopnea, such that she usually slept with 45° truncal elevation on a recliner at night. She was unable to lie flat. Her dyspnea was worse in the mornings, and she described having to "gasp" for air.

A 42-year-old white woman presented to the pulmonary clinic for evaluation of abnormal chest imaging. Twenty years prior to presentation, she was noted to have an abnormal chest radiograph during a routine preemployment evaluation. A subsequent bronchoscopy was nondiagnostic. She was followed up with annual imaging, which demonstrated little or no progression of her disease. She remained symptom free throughout this period. A year before her visit to the pulmonary clinic, she developed abdominal discomfort and was found to have ascites. Subsequently, she underwent three paracenteses with analysis revealing chylous fluid. She was a nonsmoker without a history of exposures or travel.

A 52-year-old white woman presented with severe pain over the right upper abdomen and nonpleuritic, right-sided, lower chest-wall pain. Her pain had progressively gotten more frequent and severe over the last 5 months. It was also associated with a nonexertional, pressure-like sensation in the central chest. The patient denied any shortness of breath, fevers, cough, or any sputum production. She was taking levothyroxine for hypothyroidism and was a 30-pack-year current smoker; there was no history of drug abuse or occupational exposure. Previous chest radiographs dating back to 5 years consistently showed an elevated right-sided hemidiaphragm without any infiltrates or effusions; cardiomediastinal structures were unremarkable. She had not had a previous workup for these abnormal findings.

Gaucher disease (GD), a lysosomal storage disorder, may result in end-stage lung disease. We report successful bilateral lung transplantation in a 49-year-old woman with GD complicated by severe pulmonary hypertension and fibrotic changes in the lungs. Before receiving the lung transplant, the patient was undergoing both enzyme replacement therapy (imiglucerase) and triple pulmonary hypertension treatment (epoprostenol, bosentan, and sildenafil). She had a history of splenectomy, severe bone disease, and renal involvement, all of which were related to GD and considered as relative contraindications for a lung transplantation. In the literature, lung transplantation has been suggested for severe pulmonary involvement in GD but has been reported only once in a child. To our knowledge, until now, no successful procedure has been reported in adults, and no reports deal with the severe potential posttransplantation complications specifically related to GD.