PATHOLOGY

Detailed explanation-1: -Infections of the lower respiratory tract include bronchitis, bronchiolitis and pneumonia (Fig 93-1). These syndromes, especially pneumonia, can be severe or fatal.

Detailed explanation-2: -The most common lower respiratory tract infections are bronchitis, pneumonia, and bronchiolitis. Viruses cause most lower respiratory tract infections, but bacteria can cause some pneumonias, which need treatment with antibiotics.

Detailed explanation-3: -Mild LRTIs can sometimes become more severe, leading to pneumonia, bronchitis, or other more serious infections. At times one may have a viral infection that is then complicated by a bacterial infection. Symptoms of a more serious LRTI include: Fever.