Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019621 (Langerhans cell histiocytosis)
 3,250 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The ground-glass pattern is a common but nonspecific finding on CT. In certain clinical circumstances, it can suggest a specific diagnosis, indicate a potentially treatable disease, and guide a clinician to an appropriate area for biopsy. A pattern of centrilobular ground-glass nodules is fairly specific for the diagnosis of hypersensitivity pneumonitis with the appropriate clinical history. The tree-in-bud pattern indicates disease affecting the small airways. The differential diagnosis is lengthy; however, the most common process leading to this CT appearance is infection. Although commonly associated with M. tuberculosis, many infectious organisms can produce this pattern. When honeycombing is seen on HRCT, a confident diagnosis of lung fibrosis can be made. The most common causes of interlobular septal thickening on HRCT are pulmonary edema, pulmonary hemorrhage, and lymphangitic spread of cancer, and smooth thickening is characteristic of all three. Diffuse lung cysts in patients who are not immunocompromised generally signify Langerhans' cell histiocytosis, lymphangioleiomyomatosis, or centrilobular emphysema. Centrilobular emphysema can be diagnosed when the centrilobular artery is seen as a small nodular opacity in the center of the cyst. Langerhans' cell histiocytosis is often associated with parenchymal nodules, helping to distinguish it from lymphangioleiomyomatosis. When a nodular pattern is seen on HRCT, the differential diagnosis is very long, but can be narrowed by noting whether the nodules are random, centrilobular, or perilymphatic in distribution. A mosaic pattern of lung attenuation can represent an infiltrative, small airway, or vascular process. The distinction can often be made by noting the size of the pulmonary vessels in the abnormal areas of lung, and whether air trapping is present on expiratory scanning. Computed tomographic signs can be useful indicators of a specific disease process. For instance, the air bronchogram sign indicates that an opacity is intrapulmonary in location, and signals the possibility of two types of neoplasm: lymphoma and bronchioloalveolar cell carcinoma. An air crescent sign indicates recovery of the immune system in an immunocompromised patient with invasive pulmonary aspergillosis. The fallen lung sign is diagnostic of a bronchial transection in the correct clinical setting. The gloved finger sign is very suggestive of allergic bronchopulmonary aspergillosis. The halo sign is highly suggestive of early angioinvasive pulmonary aspergillosis in patients with acute leukemia. When a split pleura sign is seen, the diagnosis is often empyema, although other causes of pleuritis can lead to a similar CT appearance.
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PMID:CT signs and patterns of lung disease. 1169 64

The aim of this pictorial essay is to illustrate the distribution of normal findings and various lung diseases on coronal reconstructions as compared with cross-sectional high-resolution CT images. The volumetric CT images were obtained at 120 kVp, 200 mA/rotation, pitch 6:1, and a high-spatial-frequency reconstruction algorithm. The scans were performed using 2.5-mm collimation and reconstructed at 1.25-mm intervals. Coronal reconstructions were obtained at 2.5-mm slice thickness and 2.5-mm intervals. The pictorial includes images of normal anatomy, emphysema, idiopathic pulmonary fibrosis, Langerhans cell histiocytosis, sarcoidosis, bronchiolitis obliterans organizing pneumonia, desquamative interstitial pneumonia, nonspecific interstitial pneumonia, lymphocytic interstitial pneumonia, pulmonary edema, tuberculosis, cytomegalovirus pneumonia, bronchiectasis, and panbronchiolitis.
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PMID:Multidetector spiral high-resolution computed tomography of the lungs: distribution of findings on coronal image reconstructions. 1236 68

Pulmonary veno-occlusive disease (PVOD) is currently classified as a subgroup of pulmonary arterial hypertension (PAH) and accounts for 5-10% of cases initially considered to be idiopathic PAH. PVOD has been described as idiopathic or complicating other conditions, including connective tissue diseases, HIV infection, bone marrow transplantation, sarcoidosis and pulmonary Langerhans cell granulomatosis. PVOD shares broadly similar clinical presentation, genetic background and haemodynamic characteristics with PAH. Compared to PAH, PVOD is characterised by a higher male/female ratio, higher tobacco exposure, lower arterial oxygen tension at rest, lower diffusing capacity of the lung for carbon monoxide, and lower oxygen saturation nadir during the 6-min walk test. High-resolution computed tomography (HRCT) of the chest can be suggestive of PVOD in the presence of centrilobular ground-glass opacities, septal lines and lymph node enlargement. Similarly, occult alveolar haemorrhage is associated with PVOD. A noninvasive diagnostic approach using HRCT of the chest, arterial blood gases, pulmonary function tests and bronchoalveolar lavage could be helpful for the detection of PVOD patients and in avoiding high-risk surgical lung biopsy for histological confirmation. PVOD is characterised by a poor prognosis and the possibility of developing severe pulmonary oedema with specific PAH therapy. Lung transplantation is the treatment of choice. Cautious use of specific PAH therapy can, however, be helpful in some patients.
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PMID:Pulmonary veno-occlusive disease. 1911 30

Severe pulmonary hypertension (PH) often develops in patients with pulmonary Langerhans cell histiocytosis (PLCH). Supplemental oxygen treatment is often used, whereas pulmonary arterial hypertension-specific vasodilators are generally considered hazardous because of the possible development of pulmonary edema and deterioration of hypoxia. In the present report, we herein describe a PLCH patient with severe PH in whom sildenafil, a phosphodiesterase 5 (PDE5) inhibitor, substantially improved the pulmonary hemodynamics before lung transplantation. An immunohistochemical study of the resected lung revealed positive staining for PDE5 on the diseased pulmonary arteries. These observations suggest that sildenafil can be a promising therapeutic option for PH in patients with PLCH.
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PMID:Severe pulmonary hypertension in adult pulmonary Langerhans cell histiocytosis: the effect of sildenafil as a bridge to lung transplantation. 2517 35

Pulmonary arterial hypertension (PAH) secondary to pulmonary Langerhans cell histiocytosis (PLCH) is known to be a relatively common complication and is associated with a poor prognosis. However, the optimal therapeutic approach for these cases remains to be established. A 57-year-old man visited our hospital because of a progressive dry cough. A thoracic computed tomography examination showed a combination of diffuse thick-walled cysts and reticulonodular shadows that were predominant in bilateral upper lobes of the lungs. He was diagnosed as having PLCH based on the results of video-assisted thoracoscopic lung biopsies. During a 3-year clinical course, his condition deteriorated despite smoking cessation. A systemic evaluation demonstrated precapillary PAH caused by PLCH (PAH-PLCH), and treatment with tadalafil, a phosphodiesterase-5 inhibitor, was started. During a 50-month period of treatment with tadalafil, improvements in his dyspnea, 6-min walking distance, and hemodynamics were maintained without either overt hypoxemia or pulmonary edema. We considered that tadalafil therapy may be a useful option in the treatment of patients with PAH-PLCH.
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PMID:Long-term improvement during tadalafil therapy in a patient with pulmonary hypertension secondary to pulmonary Langerhans cell histiocytosis. 2733 Sep 52