Mataracy
VIP Contributor
Active fibrous - tissue formation can occur around the tubercles. The fibrous tissue constitute an attempt by the body to wall off the infection and heal the lesion by scar - tissue formation.
In most cases caseation and slight fibrosis are present together. Marked caseation and slight fibrosis are evidence of severe infection and little effort on the part of the body to heal. Alternatively , when fibrosis is marked , then the disease is usually arrested or limited. Sometimes calcium is deposited in the caseated mass, and this calcified lesion is also usually arrested or healed.
The commonest entry of tubercle bacilli is by inhalation. When sputum is expectorated from someone with pulmonary tuberculosis, the tubercle bacilli can survive for many months . Infection can occur by inhaling dust which contains the bacilli or by direct droplet infection. The respiratory tract can be affected in different ways:
(1) pulmonary tuberculosis. The upper lobes of the lungs are particularly liable to be involved with infiltration and spread of the disorder to other parts of the lung. Caseation may occur with formation of cavities.
(2) Infection of the pleura leads to pleurisy and pleural effusion.
(3) Miliary tuberculosis. The bacteria invade the blood stream and small tubercles appear through out the longs and many other organs as well, especially the liver.
In most cases caseation and slight fibrosis are present together. Marked caseation and slight fibrosis are evidence of severe infection and little effort on the part of the body to heal. Alternatively , when fibrosis is marked , then the disease is usually arrested or limited. Sometimes calcium is deposited in the caseated mass, and this calcified lesion is also usually arrested or healed.
The commonest entry of tubercle bacilli is by inhalation. When sputum is expectorated from someone with pulmonary tuberculosis, the tubercle bacilli can survive for many months . Infection can occur by inhaling dust which contains the bacilli or by direct droplet infection. The respiratory tract can be affected in different ways:
(1) pulmonary tuberculosis. The upper lobes of the lungs are particularly liable to be involved with infiltration and spread of the disorder to other parts of the lung. Caseation may occur with formation of cavities.
(2) Infection of the pleura leads to pleurisy and pleural effusion.
(3) Miliary tuberculosis. The bacteria invade the blood stream and small tubercles appear through out the longs and many other organs as well, especially the liver.
