Tuberculosis Transmission and Risk Factors Quiz

Tuberculosis Transmission and Risk Factors

• Tuberculosis (TB) is transmitted through airborne droplet nuclei released from a person with untreated pulmonary TB (PTB), and through ingestion of unpasteurized milk from infected cattle.
• Risk factors for TB include age below 5 or above 14 years, contact with adults with chronic cough, birth in endemic countries or IDP camps, malnutrition, poverty, HIV infection, measles, pertussis, diabetes, and other immunosuppressive conditions.
• Common sites of TB disease include the lungs, pleura, abdomen, central nervous system, lymph nodes, genitourinary systems, bones and joints, and disseminated (miliary TB).
• The natural history of TB varies, with different forms of TB having different timetables for progression, ranging from a few months to over 10 years.
• Clinical features of TB depend largely on the site of infection and may include weight loss, anorexia, night sweats, generalized lymphadenopathy, fever, cough, pleuritic chest pain, hemoptysis, neck swelling, abdominal distension, abdominal pain, and ascites.
• Pulmonary TB is the most common form, occurring alone in 90% of cases or in combination with other forms in over 70% of cases.
• Common symptoms of pulmonary TB include cough lasting 3 weeks, low-grade continuous fever, anorexia, weight loss, night sweats, pleuritic chest pain, and hemoptysis.
• Common signs on respiratory system examination for pulmonary TB include dyspnea, tachypnea, dull percussion notes, increased tactile fremitus, localized wheezing, decreased breath sounds, rales, and bronchial breath sounds.
• TB spine, also known as Pott's disease, is the rare but most common TB bone disease in children, which can lead to lytic destruction of the vertebrae and clinical findings such as gibbus, reduced power in the lower limbs, and brisk reflexes.
• TB adenitis is the most common form of extra-pulmonary TB infection, characterized by chronic granulomatous inflammation of the lymph nodes with caseation necrosis forming a tuberculous granuloma often close to the collar bone.
• Extra-pulmonary TB involving abdominal organs such as intestines, peritoneum, liver, or abdominal lymph nodes accounts for about 5% of global TB cases, with gastrointestinal TB being the most common form.
• TB of the central nervous system may occur as TB meningitis or a tuberculoma, and diagnosis involves specific investigations such as FBC ESR, Mantoux, sputum AFB microscopy, chest X-ray, biopsy, histology, abdominal USS, LP/CT/MRI, TB gold test, GeneXpert, PCR, and culture of specimens.

Tuberculosis: Causes, Transmission, and Clinical Features

• Tuberculosis (TB) is transmitted through airborne droplet nuclei released by coughing, spitting, or sneezing of TB bacilli, with primary infection in children often following prolonged contact with untreated adult cases.
• TB can also be transmitted through ingestion of unpasteurized milk from infected cattle, and risk factors for TB include age, contact with chronic cough, birth in an endemic country, malnutrition, poverty, HIV infection, and other immunosuppressive conditions.
• Common sites of TB disease include the lungs, pleura, abdomen, central nervous system, lymph nodes, genitourinary systems, bones and joints, and disseminated (miliary TB).
• The natural history of TB includes different timetables for various forms of the disease, such as pulmonary TB (PTB), miliary and meningeal TB, TB adenitis, and others.
• Clinical features of TB largely depend on the site of infection, with constitutional symptoms and signs including weight loss, anorexia, night sweats, generalized lymphadenopathy, fever, cough, pleuritic chest pain, and specific findings like neck swelling and abdominal distension.
• Pulmonary TB is the most common form of TB and can occur alone or in combination with other forms, with upper lung lobes affected more frequently than lower lobes.
• Symptoms of pulmonary TB include cough, fever, anorexia, weight loss, night sweats, pleuritic chest pain, and signs on respiratory system examination such as dyspnea, tachypnea, dull percussion notes, and decreased breath sounds.
• TB spine, also known as Pott's disease, is a rare but common bone disease in children, typically affecting the lower thoracic vertebrae, lumbar, upper thoracic, and sacral regions, with clinical findings including gibbus and reduced power in the lower limbs.
• TB adenitis is the most common form of extra-pulmonary TB infection, characterized by chronic granulomatous inflammation of lymph nodes with caseation necrosis forming a tuberculous granuloma often close to the collar bone.
• Extra-pulmonary TB involving abdominal organs may occur in isolation or alongside pulmonary TB, with gastrointestinal TB being the most common form and the ileocecal junction the most involved region.
• TB of the central nervous system may occur as TB meningitis or a tuberculoma, and diagnosis includes specific investigations such as FBC ESR, Mantoux, sputum AFB microscopy, chest X-ray, biopsy, histology, abdominal USS, LP/CT/MRI, TB gold test, GeneXpert, PCR, and culture of specimens.
• The Mantoux test is used for TB diagnosis, with interpretation based on the size of the induration, with positive results indicating TB infection, particularly in high-risk groups such as HIV-infected children and severely malnourished children.

Tuberculosis: Key Points

• Tuberculosis (TB) can be transmitted through airborne droplets released by untreated adult pulmonary TB (PTB) cases, or through ingestion of unpasteurized milk from infected cattle.
• Risk factors for TB include age below 5 years or above 14 years, contact with a chronic cough, birth in an endemic country, malnutrition, poverty, HIV infection, and other immunosuppressive conditions.
• Common sites of TB disease include the lungs, pleura, abdomen, central nervous system, lymph nodes, genitourinary systems, bones and joints, and disseminated (miliary TB).
• The natural history of TB varies, with PTB taking a few months, miliary and meningeal TB taking 2-6 months, TB adenitis taking 3-9 months, and bones and joints taking several years.
• Clinical features of TB depend on the site of infection and may include weight loss, anorexia, night sweats, fever, cough, pleuritic chest pain, hemoptysis, neck swelling, and abdominal distension.
• Pulmonary TB is the most common form, occurring alone or in combination with other forms in more than 70% of cases, and often presents with cough, fever, anorexia, weight loss, night sweats, and pleuritic chest pain.
• TB spine, also known as Pott's disease, is the rare but most common TB bone disease in children, and often affects the lower thoracic vertebrae.
• TB adenitis is the most common form of extrapulmonary TB infection, characterized by chronic granulomatous inflammation of lymph nodes and cold abscess formation.
• TB abdomen involves abdominal organs such as intestines, peritoneum, liver, or abdominal lymph nodes, with gastrointestinal TB being the most common form.
• TB of the central nervous system may occur as TB meningitis or a tuberculoma.
• Diagnosis of TB involves specific investigations such as FBC, ESR, Mantoux test, sputum AFB microscopy, chest X-ray, biopsy and histology, abdominal USS, LP/CT/MRI, TB gold test, GeneXpert, PCR, and culture of specimens.
• Mantoux test interpretation varies with 0-4mm indicating a negative result, 5-9mm borderline, and ≥10mm positive, irrespective of BCG vaccination status.