A computer-aided diagnosis system for quantitative scoring of extent of lung fibrosis in scleroderma patients.

OBJECTIVES: To evaluate an improved quantitative lung fibrosis score based on a computer-aided diagnosis (CAD) system that classifies CT pixels with the visual semi-quantitative pulmonary fibrosis score in patients with scleroderma-related interstitial lung disease (SSc-ILD). METHODS: High-resolution, thin-section CT images were obtained and analysed on 129 subjects with SSc-ILD (36 men, 93 women; mean age 48.8±12.1 years) who underwent baseline CT in the prone position at full inspiration. The CAD system segmented each lung of each patient into 3 zones. A quantitative lung fibrosis (QLF) score was established via 5 steps: 1) images were denoised; 2) images were grid sampled; 3) the characteristics of grid intensities were converted into texture features; 4) texture features classified pixels as fibrotic or non-fibrotic, with fibrosis defined by a reticular pattern with architectural distortion; and 5) fibrotic pixels were reported as percentages. Quantitative scores were obtained from 709 zones with complete data and then compared with ordinal scores from two independent expert radiologists. ROC curve analyses were used to measure performance. RESULTS: When the two radiologists agreed that fibrosis affected more than 1% or 25% of a zone or zones, the areas under the ROC curves for QLF score were 0.86 and 0.96, respectively. CONCLUSIONS: Our technique exhibited good accuracy for detecting fibrosis at a threshold of both 1% (i.e. presence or absence of pulmonary fibrosis) and a clinically meaningful threshold of 25% extent of fibrosis in patients with SSc-ILD.

Nocardia prostatitis in a small intestine transplant recipient.

A 37-year-old small bowel transplant recipient with a history of urolithiasis was admitted for dysuria after passing a urinary stone. His laboratory evaluation showed increased blood urea nitrogen and creatinine. Urinalysis showed increased white blood cells and positive leukocyte esterase. A computed tomography scan revealed signs of urinary tract obstruction and prostatic enlargement. He failed to respond initially to empiric antibiotic treatment with ciprofloxacin and ampicillin sulbactam while waiting for culture results. The pathogen recovered from both urine and blood culture was subsequently identified as Nocardia asteroides complex. The isolate was sensitive to ceftriaxone and sulfa but resistant to ciprofloxacin. The patient improved on ceftriaxone and trimethoprim-sulfamethoxazole and completed a 6-month course without any relapse. Nocardia prostatitis is an uncommon infection and must be treated with a long course of antibiotics guided by susceptibility testing.

Cavitary pneumonia due to Rhodococcus equi in a heart transplant recipient.

Rhodococcus equi is an uncommon human pathogen that usually affects immunocompromised patients. We present a case of a 68-year-old male heart transplant recipient, who developed rhodococcal pneumonia with secondary bacteremia 10 months post-transplant. The patient was a retired carpenter who was involved in breeding of horses. He responded completely to the treatment with vancomycin and imipenem/cilastin, followed by oral ciprofloxacin and minocycline for total treatment duration of 5 months. This case highlights the association between an animal exposure and infection with a unique opportunistic pathogen.

Legionellosis in a lung transplant recipient obscured by cytomegalovirus infection and Clostridium difficile colitis.

A 52-year-old-white male underwent double lung transplantation for severe emphysema due to alpha-1-antitrypsin deficiency and heavy tobacco use. Following a postoperative course complicated by renal insufficiency, pulmonary emboli, and Clostridium difficile colitis, he was discharged in stable condition. Two months later, he was admitted to a local hospital with a fever, abdominal pain, diarrhea, nausea, and dyspnea. Computerized tomography (CT) of the chest revealed bilateral pleural effusions. Sigmoidoscopy was grossly normal but biopsy demonstrated cytomegalovirus (CMV) colitis, and the patient was placed on intravenous ganciclovir. Over the next week, he became progressively hypoxemic and was transferred to the University of Pittsburgh Medical Center (post-transplant day 81) for further evaluation. His medications on transfer included: ganciclovir, prednisone, tacrolimus, dapsone, fluconazole, ondansetron, lansoprazole, digoxin, and coumadin.

Tumors of the thymus.

Thymic neoplasms are a common cause of an anterior mediastinal mass and may be benign or malignant. Thymic cysts are congenital or acquired and may be associated with a thymic malignancy. True thymic hyperplasia and thymic lymphoid hyperplasia may enlarge the thymus and simulate a neoplasm. Thymoma and thymic carcinoma are epithelial malignancies with distinct clinicopathologic features. Thymic carcinoid is a rare aggressive neuroendocrine malignancy associated with multiple endocrine neoplasia 1. Thymolipoma is a benign neoplasm. Hodgkin and non-Hodgkin lymphoma may primarily or secondarily involve the thymus. Primary mediastinal germ cell tumors may arise primarily within the thymus and include mature teratoma, seminoma, and non-seminomatous malignant germ cell tumors.

Primary mediastinal tumors: part II. Tumors of the middle and posterior mediastinum.

Lymphoma, mediastinal cysts, and neurogenic neoplasms are the most common primary middle and posterior mediastinal tumors. Lymphoma may involve the anterior, middle and/or posterior mediastinum, frequently as lymphadenopathy or as a discrete mass. Foregut cysts are common congenital mediastinal cysts and frequently arise in the middle mediastinum. Pericardial cysts are rare. Schwannoma and neurofibroma are benign peripheral nerve neoplasms, represent the most common mediastinal neurogenic tumors, and rarely degenerate into malignant tumors of nerve sheath origin. Sympathetic ganglia tumors include benign ganglioneuroma and malignant ganglioneuroblastoma and neuroblastoma. Lateral thoracic meningocele is a rare cause of a posterior mediastinal mass.

Primary mediastinal tumors. Part 1: tumors of the anterior mediastinum.

Primary anterior mediastinal neoplasms comprise a diverse group of tumors and account for 50% of all mediastinal masses. Thymomas are most common and can be locally invasive and associated with parathymic syndromes. Thymic carcinomas and thymic carcinoids are rare malignancies with a propensity for local invasion and distant metastases. Thymolipomas are benign thymic tumors. The mediastinal germ cell tumors are a heterogeneous group of benign and malignant neoplasms. Mediastinal lymphangiomas are rare tumors and predominantly occur in young children. In contrast, mediastinal goiters are relatively common in adults. Mediastinal parathyroid adenomas are an uncommon cause of persistent hyperparathyroidism and rarely cause a discernible mass. The clinical, radiologic, and therapeutic aspects of the most common masses are reviewed.

Pulmonary mucormycosis: radiologic findings in 32 cases.

OBJECTIVE: The purpose of this study was to characterize the radiologic manifestations of pulmonary mucormycosis with clinical and pathologic correlation. MATERIALS AND METHODS: Clinical records, pathology reports, chest radiographs, and CT scans of 32 cases of pathologically proven pulmonary mucormycosis were retrospectively reviewed. RESULTS: The study group included 20 males and 12 females with a mean age of 47 years old. Clinical data were available for 29 patients. Signs and symptoms included fever (n = 23), cough (n = 21), bloody sputum (n = 9), dyspnea (n = 7), and chest pain (n = 6). Four patients were asymptomatic. Most patients were either immunocompromised (n = 20) or had diabetes mellitus (n = 9). Sputum or bronchoalveolar lavage cultures showed no growth in 17 of 18 cases. Diagnoses were confirmed at surgery or autopsy in all cases. Abnormalities seen on chest radiographs included lobar (n = 15) or multilobar (n = 6) consolidation, solitary (n = 7) or multiple (n = 1) masses, and solitary (n = 3) or multiple (n = 2) nodules. Cavitation was seen on chest radiographs in 13 patients, and intracavitary masses were seen in four. Associated radiographic findings included hilar (n = 3) or mediastinal (n = 3) adenopathy and unilateral (n = 6) or bilateral (n = 3) pleural effusion. CT in 19 patients revealed these significant additional findings: splenic (n = 1) or renal (n = 1) involvement, bronchial occlusion (n = 1), extrapulmonary invasion (n = 1), and pulmonary artery pseudoaneurysm (n = 1). CONCLUSION: In our study, pulmonary mucormycosis typically was manifested in immunocompromised or diabetic patients by consolidation on chest radiographs; cavitation was seen in 40% of patients. CT revealed significant unsuspected abnormalities in 26% of patients. Definitive diagnosis required pathologic demonstration of the organism in affected tissue because cultures from our patients rarely showed growth.

Imaging of the normal trachea.

Tracheal evaluation is a fundamental part of chest imaging. Adult tracheal anatomy is well understood, but tracheal embryology is not. There have been major advances in imaging, but radiography remains the initial imaging study for most tracheal pathology. Careful radiographic analysis can yield considerable information.

Pulmonary eosinophils express HLA-DR in chronic eosinophilic pneumonia.

BACKGROUND: Chronic eosinophilic pneumonia is a rare idiopathic disorder. role the eosinophil plays in the pathogenesis of this disease is unknown. The recent finding that nature eosinophils can express the class II major histocompatibility complex molecule HLA-DR suggests an immunologic role, perhaps through antigen presentation. The purpose of this research was to determine whether lung-derived eosinophils exhibit in vivo expression of HLA-DR. METHODS: Eosinophils were obtained simultaneously from bronchoalveolar lavage and peripheral blood from a 59-year-old woman with asthma and chronic eosinophilic pneumonia. Eosinophil-enriched aliquots of peripheral blood were cocultured with human lung fibroblasts (with or without additional granulocyte-macrophage colony-stimulating factor). The percentage of cells expressing HLA-DR was quantitated by flow cytometric analysis. RESULTS: Eosinophils derived from bronchoalveolar lavage displayed in vivo expression of HLA-DR (86%) in contrast to those from peripheral blood (7%), suggesting compartmentalization of eosinophil activation within the lung. Peripheral blood eosinophils retained the capacity for HLA-DR expression when coincubated with lung fibroblasts (83%) with augmentation by granulocyte-macrophage colony-stimulating factor (93%). CONCLUSION: These data demonstrate that lung eosinophil HLA-DR expression occurs in vivo; it may contribute to the pathogenesis of inflammatory lung injury.