Pathogenesis and Natural History of Usual Interstitial Pneumonia: Pathology of IPF

Pathogenesis and Natural History of Usual Interstitial Pneumonia: Pathology of IPF

Idiopathic interstitial pneumoniasIdiopathic interstitial pneumonias are a heterogeneous group of diffuse parenchymal lung disorders resulting from damage to the lung parenchyma by varying patterns of inflammation and fibrosis. In 2002, the American Thoracic Society/European Respiratory Society classified1 idiopathic interstitial pneumonias into seven distinct entities based on clinical manifestations, pathology, and radiologic features (Table 1). One of these entities, idiopathic pulmonary fibrosis (IPF), is a progressive, fatal disease. IPF has been defined in an American Thoracic Society/European Respiratory Society consensus statement1 as a type of chronic fibrosing interstitial pneumonia of unknown etiology that is limited to the lungs and is associated with surgical biopsy specimens showing a histologic pattern of usual interstitial pneumonia (UIP). UIP histopathology is not unique to IPF, and has been reported in asbestosis, chronic hypersensitivity pneumonitis, and collagen vascular disorders with associated interstitial lung disease.

While ongoing research continues to investigate multiple hypotheses of UIP pathogenesis, neither the natural history nor the pathogenesis of UIP is currently well understood. To determine whether UIP represents the end stage of IPF, it is important to elucidate the complete natural history and pathogenesis of IPF, which would allow the investigation of potentially different mechanisms that may be operative at the early, intermediate, and end stages of the disease. This knowledge could lead to the implementation of targeted therapeutic interventions at specific stages of the disease process. Continue reading “Pathogenesis and Natural History of Usual Interstitial Pneumonia: Pathology of IPF”

Results of Etiology and Outcome of Community-Acquired Pneumonia in Patients With Diabetes Mellitus

Results of Etiology and Outcome of Community-Acquired Pneumonia in Patients With Diabetes Mellitus

etiologySeven hundred twenty-six patients showing clinical and radiologic findings of community-acquired pneumonia were enrolled in the study; however, 66 patients were subsequently excluded from the study for the following reasons: misdiagnosis at enrollment (n = 59); nosocomial acquisition hospitalization (n = 4); and consent not obtained (n = 3). Thus, 660 patients constituted the final study group. Underlying diseases were found in 324 patients (49%), among which COPD (114 patients), diabetes mellitus (106 patients), and congestive heart disease (58 patients) were the most common.

The subgroup of patients with diabetes mellitus was mainly constituted by patients with type 2 diabetes, which was diagnosed in 100 patients (94%). The mean duration of illness was 8 years, although for 14 patients the diagnosis was established during the present episode of pneumonia. At study entry, the mean plasma glucose level was 238 mg/dL, and the mean hemoglobin A1c value was 8.1%. Diabetes-related complications were common among these patients; thus, 20 patients (19%) had diabetic retinopathy, 18 patients (17%) had diabetic nephropathy, 18 patients (17%) had experienced major mac-rovascular events (eg, ischemic heart disease, stroke, or intermittent claudication), and 5 patients (5%) had peripheral polyneuropathy; for only 56 patients were complications absent. In addition to diet, 59 patients (56%) were receiving treatment with oral agents, and 40 patients (38%) were receiving treatment with insulin (both therapies were simultaneously used in 18 patients); however, during pneumonia 95 patients (90%) needed insulin therapy.

Continue reading “Results of Etiology and Outcome of Community-Acquired Pneumonia in Patients With Diabetes Mellitus”