Which of the following ilineses increases the risk of developing tuberculosis ?

Because silica is cytotoxic to alveolar macrophages,patients with silicosis are at greater risk of acquiring lung infections that involve these cells as a primary defense(Mycobacterium tuberculosis,atypical mycobacteria and fungi).Because of the increased risk of active tuberculosis,the recommended treatment of latent tuberculosis in these patients is longer.Another potential clinical complication of silicosis is autoimmune connective tissue disorders such as rheumatoid ahritis and scleroderma,as well as lung cancer. Reference:Harrison's medicine-18th edition,page no:2125.