Continuous Positive Airway Pressure (CPAP) in Non-Apneic Asthma: A Clinical Review of Current Evidence.

The use of continuous positive airway pressure (CPAP) in asthma has been a point of debate over the past several years. Various studies, including those on animals and humans have attempted to understand the role and pathophysiology of CPAP in patients with either well controlled or poorly controlled asthma. The aim of this manuscript is to review the currently available literature on the physiologic and clinical effects of CPAP in animal models of asthma and on humans with stable asthma.

A 44-Year-Old Man With Dyspnea and a Pulmonary Artery Filling Defect.

CASE PRESENTATION: A 44-year-old man with a history of coronary artery disease, type 2 diabetes mellitus, and OSA reported progressively worsening dyspnea on exertion over a 6-week period. Outpatient CT angiogram revealed a pulmonary artery filling defect. He was sent to the ED where he was started on a heparin drip for unprovoked pulmonary embolism (PE). Echocardiogram revealed normal cardiac function without evidence of right heart strain. Lower extremity ultrasound was negative for DVT. He improved symptomatically, and no risk factors for PE were identified. He was discharged on apixaban. Five weeks later, the patient returned to the ED with hemoptysis. He reported compliance with anticoagulation and improvement of his dyspnea on exertion. History remained negative for recent travel, trauma, surgery, clotting disorders, thromboembolic disease, and alcohol or drug use. He had a 60 pack-year cigarette smoking history and quit 3 months prior.

Chitin, chitinases, and chitin lectins: Emerging roles in human pathophysiology.

Chitin is a simple ß-linked repeating sugar polymer prominent in the building block structures of a wide variety of organisms, from the yeast cell wall to the exoskeleton and shells of arthropods and other forms of invertebrate life. It had previously been assumed that vertebrates did not contain chitins. However, chitin and chitinases are now documented to occur in vertebrate tissues. Chitin, chitinases and particularly chitinase-like proteins are involved in important human pathologies, though the mechanisms by which these function is unknown. These chitinase-like proteins bind to chitin and function as chitin lectins in that they bind to chitin but have lost the ability to degrade it. Emphasis is placed on one of the chitinase-like proteins, CHI3L1, that has acquired wide clinical importance. The purpose of this review is to place an array of bewildering observations associated with various human disorders into a framework, particularly the pathologies of the human gastro-intestinal tract. A reasonably cohesive story may eventually emerge.