Name: Dešiniojo Plaučių Miliarinės Tuberkuliozės 3D Modelis Erler-Zimmer Right Lung Miliary Tuberculosis 3D Printed Model - Labostera
SKU: MP2060
Availability: InStock

Erler-Zimmer GmbH & Co. KG 3D model of miliary tuberculosis of the right lung:

Model Number: MP2060
Clinical history:
A 74-year-old man presented with increasing dyspnea and hemoptysis. Additional history revealed that he had lost 20 kg of weight in 6 months, had night sweats, and had a persistent cough. He had recently migrated from a country where tuberculosis is endemic. On examination, he was hypoxemic and tachypneic, and had crepitations in both lung fields and dull rales at the base of the left lung. His quantiferon gold blood test was positive. Chest radiography showed bilateral small nodules and left-sided pneumonia. He died of respiratory failure after admission.
Pathology:
The right lung has been cut longitudinally and fixed to expose the cutting surface. The bronchi and bronchioles are slightly dilated. Throughout the lung tissue there are large confluent small, pale yellow spots, less than 1 mm in diameter. Similar small subcircular nodules are seen on the inner lining. The nodules are tubercles. This is miliary tuberculosis, so called because of its resemblance to the nodules of millet grains.
Additional information:
Tuberculosis (TB) is a chronic pulmonary and systemic disease caused by Mycobacterium tuberculosis. Transmission is mainly by inhalation of aerosolized droplets of this pathogenic bacterium, first described by Robert Koch (1882). Risk factors associated with TB infection include living in a developing country where the disease is endemic, immunosuppression (e.g., HIV, steroid use, anti-TNF use, and diabetes), chronic lung disease (e.g., silicosis), alcoholism, and malnutrition.
After initial pulmonary infection with M. tuberculosis, the clinical presentation is variable. 90% people with an intact immune system enter an asymptomatic latent infection stage. This latent TB can reactivate at any time during the patient's life. Other 10% patients, especially those who are immunosuppressed, develop primary disease, which is immediately active M. tuberculosis infection. Primary TB manifestations include symptoms of pulmonary infection (e.g., consolidation, effusion, and hilar adenopathy) and extrapulmonary symptoms including lymphadenopathy, meningitis, and disseminated miliary TB.
Secondary tuberculosis occurs when previously latent M. tuberculosis is reactivated. Approximately 101% of latent TB cases will reactivate, usually during periods of weakened host immune response. Symptoms of reactivation include cough, hemoptysis, low-grade fever, night sweats, and weight loss.
Miliary TB occurs when the mycobacterium erodes into the pulmonary vein and seeds elsewhere. The organism can circulate back to the lungs and disseminate through the lung tissue, as in this case. Systemic miliary TB can occur when the mycobacterium spreads through the arterial system. The TB can then settle in any organ, but most commonly in the liver, bone marrow, spleen, and adrenal glands.
The immune response to TB is mediated by TH1 cells, which stimulate alveolar macrophages to attack the mycobacterium. These macrophages surround the infection, forming a granuloma surrounding a centre with a 'cine' (white cottage cheese-like) area of necrosis. Secondary pulmonary TB may heal with fibrosis or progress, as in this case. Progressive pulmonary tuberculous processes lead to erosion of the infectious focus and extension into adjacent lung tissue. This leads to evacuation of the cine centre, resulting in fibrotic cavitation. Erosion of blood vessels may occur, causing haemoptysis. After TB treatment, the tissue heals with fibrosis, but the lung architecture does not return.
The diagnosis of TB is usually made by clinical history, chest X-rays, and multiple saliva cultures. The Mantoux skin test and serum interferon gamma release assay can also be used to help diagnose the infection. Biopsies may be taken from suspected sites of infection for culture to help confirm the diagnosis. Treatment involves long-term use of multiple antibiotics, depending on the antibiotic resistance of the mycobacterium causing the infection.