Other Infections Timothy C. Allen MD, JD Philip T. Cagle MD Other infections occasionally occur in the lung and some may be identified on transbronchial biopsy. Rickettsiae, obligate intracellular bacteria,…

Fungus Abida Haque MD Anna Sienko MD Philip T. Cagle MD Fungi are eukaryotic, unicellular organisms that are abundant in nature but rarely cause disease. Fungi are larger and genomically…

Mycobacteria Abida Haque MD Anna Sienko MD Philip T. Cagle MD Mycobacterium tuberculosis is an acid-fast bacillus (AFB), 0.5 × 4 to 5 μm, and the etiologic agent of tuberculosis…

Pneumocystis jiroveci Abida Haque MD Anna Sienko MD Philip T. Cagle MD Pneumocystis pneumonia is one of the most common pulmonary infections in patients with acquired immunodeficiency syndrome (AIDS) and…

Mycoplasma Pneumonia Armando E. Fraire MD Pneumonia due to Mycoplasma pneumoniae ranks among the most common variants of community-acquired pneumonia, affecting primarily children, adolescents, and young adults, notably more frequently…

Bacterial Pneumonia Armando E. Fraire MD Abida Haque MD Clifford G. Risk MD Several decades after the introduction of modern antimicrobials, bacterial pneumonia remains a major cause of morbidity and…

Viruses Abida Haque MD Philip T. Cagle MD Viral infections of lung are common, and often latent and self-limited except in immunocompromised patients, who can develop extensive pulmonary infections with…

Benign Neoplasms Keith M. Kerr FRCPath Benign neoplasms of the lung are numerous, heterogeneous, and rare. Most occur in the lung periphery, neither visible to the bronchoscopist nor likely to…

Hematolymphoid Malignancies Timothy C. Allen MD, JD Keith M. Kerr FRCPath Jaishree Jagirdar MD Bronchial-associated lymphoid tissue is an ordinary finding in bronchial biopsies, and benign lymphocytic infiltrates are very…

Metastatic Cancers Keith M. Kerr FRCPath The lungs are the most common site, after the liver, for metastatic cancer, and, as a clinical problem, pulmonary metastases are more frequently encountered…