Miliary tuberculosis is a potentially life-threatening type of tuberculosis that occurs when a large number of the bacteria travel through the bloodstream and spread throughout the body. Handwritten video lecture on Extrapulmonary TB for USMLE Step 1 and USMLE Step 2. renal tuberculosis. Primary infection, which is transmitted via airborne droplets, is often initially asymptomatic. App. • The recommended treatment of new-onset pulmonary tuberculosis, as of 2010, is six months of a combination of antibiotics containing rifampicin, isoniazid, pyrazinamide, and ethambutol for the first two months, and only rifampicin and isoniazid for the last four months. • Extrapulmonary TB most commonly involves lymph Advanced age, HIV/AIDS, steroid use, biologic drugs, Failure of granulomas to contain bacterial spread, Bacteria are predisposed to apex likely due to increased oxygen tension, Liquefactive and caseating necrosis causes cavitation, Widespread dissemination and seeding results in little focuses resembling millet seeds (hence, “miliary”), TB osteomyelitis caused by vertebral involvement, Pericarditis, mediastinitis, skin lesions, and hepatic lesions also seen, Real-time nucleic acid amplification (PCR), PPD stands for purified protein derivative, Test for prior exposure + cell-mediated immunity (type 4 HSR), False negative result seen in immunocompromised patients, False positive in BCG (Bacille Calmette-Guerin) vaccination, healthcare worker, traveling to endemic areas, and being in prison), HIV, on immunosuppressants, and organ transplant recipients), Positive tests require a chest radiograph, Measure amount of IFN-gamma released by T-cells when exposed to TB antigens, Test prior exposure and cell-mediated immunity, Preferred over PPD b/c BCG-vaccinated people are negative. The main cause of TB is Mycobacterium tuberculosis (MTB), a small, aerobic, nonmotile bacillus. Mode of transmission … Miliary tuberculosis Widespread dissemination and seeding results in little focuses resembling millet seeds (hence, “miliary”) Kidneys are commonly affected, resulting in sterile pyuria, or high levels of white blood cells in the urine. The primary infection is usually asymptomatic (the majority of cases), although a small number go on to have symptomatic hematological dissemination which may result in miliary tuberculosis. Where resistance to isoniazid is high, ethambutol may be added for the last four months as an alternative. Tuberculosis (TB) is an ancient human disease caused by Mycobacterium tuberculosis which mainly affects the lungs, making pulmonary disease the most common presentation (K Zaman, 2010) .However, TB is a multi-systemic disease with a protean presentation. Summary Tuberculosis (TB) is a common infectious cause of morbidity and mortality worldwide that is caused by Mycobacterium tuberculosis and typically affects the lungs. Miliary tuberculosis (TB) refers to clinical disease resulting from hematogenous dissemination of Mycobacterium tuberculosis. He also has pain and swelling of hands and feet for 3 months. 25% (81/325) M 2 E Select Answer to see Preferred Response. If a Gram stain is performed, MTB either stains very weakly “Gram-positive” or does not retain dye as a result of the high lipid and mycolic acid content of its cell wall. Significant nail clubbing may also occur. Case Discussion. Tuberculosis (TB) is a serious infection that usually affects only your lungs, which is why it’s often called pulmonary tuberculosis. Will be discussing pathophysiology, signs and symptoms, diagnosis and treatment. • Miliary TB implies hematogenous spread which can The patient is HIV negative, denies drug use, and denies sick contacts. RIPE is 1st line treatment for active pulmonary TB. Mycobacterium bovis. Lymphadenitis ( scrofula, cervical LN common) ... USMLE QUIZ ! lymphadenitis, and rarely erythema nodosum. • Latent phase:  Mycobacteria enter a latent phase after the resolution of Miliary Tuberculosis List of authors. • Latent TB is treated with either isoniazid alone or a combination of isoniazid with either rifampicin or rifapentine. Treatment for Latent TB Infection and Pregnancy. Additional reasonable indications are pericarditis, lymphadenitis associated with compressive symptoms, and prominent persistent constitutional symptoms. depends on the concentration of bacilli, duration of Tuberculosis (TB) encompasses a variety of diseases caused by M. tuberculosis and less commonly Causes. The high lipid content of this pathogen accounts for many of its unique clinical characteristics. A direct measurement tool for M. tuberculosis infection in humans is currently unavailable. Meningism is absent in a fifth of patients with TB meningitis. To the naked eye, this has the texture of soft, white cheese and is termed caseous necrosis. Subscribe to Youtube. Bacteria inside the granuloma can become dormant, resulting in latent infection. Latent tuberculosis infection (LTBI) - FAQs What is LTBI? The granuloma may prevent the dissemination of the mycobacteria and provide a local environment for the interaction of cells of the immune system. Extrapulmonary TB occurs when tuberculosis develops outside of the lungs, although extrapulmonary TB may coexist with pulmonary TB. makes it easy to get the grade you want! Uveal tract, salivary and lacrimal glands, heart and skeletal muscles, liver and spleen and small bones of hand and feet are commonly involved in sarcoidosis but are rarely seen in tuberculosis. TB is caused by a bacterium called Mycobacterium tuberculosis. [Reminder: PPD = Type lV Hypersensitivity]. Tuberculosis may infect any part of the body, but most commonly occurs in the lungs (known as pulmonary tuberculosis). Mycobacterium tuberculosis of the meninges is the cardinal feature and the inflammation is concentrated towards the base of the brain. Addison disease( adrenal TB) Salpingitis( chronic PID) Pott disease and Paraspinal "cold" abscesses. lesion or disseminated infection. • Extrapulmonary TB most commonly involves lymph nodes, pleura, genitourinary tract, meninges, pericardium, bones, and joints. the primary infection which may last from months to years. The organ system most commonly affected include the respiratory system, the gastrointestinal (GI) system, the … The lesions in the liver and spleen came from blood-borne spread of the bacillus from the lesion in the lung (the lesions in the spleen and liver would be called miliary TB). Match. Secondary tuberculosis. However, more recent evidence suggests that the bacteria use the granulomas to avoid destruction by the host’s immune system. In this type the source of organism is exogenous and about 5% of newly infected develop significant disease. On examination, he has synovitis of proximal interphalangeal joints of both hands. Miliary tuberculosis is present in about 2% of all reported cases of tuberculo… Gravity. Lymphatic TB is found Its name comes from a distinctive pattern seen on a chest radiograph of many tiny spots distributed throughout the lung fields with the appearance similar to millet seeds—thus the term "miliary" tuberculosis. Xiang-Dong Mu, M.D., and Guang-Fa Wang, M.D. PLAY. Another feature of the granulomas is the development of abnormal cell death (necrosis) in the center of tubercles (a small nodular lesion). Systemic miliary tuberculosis: tuberculous meningitis. 1% (3/325) 5. exposure, and host immunity. nodes, pleura, genitourinary tract, meninges, pericardium, bones, and joints.
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