The cytologic features of common inflammatory processes, such as organizing pneumonia, bronchiolitis obliterans obstructing pneumonia and diffuse alveolar damage, are considerably overlapping. Inflammatory cells are observed, such as macrophages, neutrophils, eosinophils and lymphocytes. Reactive pneumocytes are especially common in organizing pneumonia and diffuse alveolar damage. The lung is the most common site of sarcoidosis, which […]

Respiratory infections

Cytology plays an important role in diagnosing infectious diseases in immunocompromised patients. Conventional inflammatory response may be much reduced, absent or greatly altered in these patients. Viral infections Bacterial infections Fungal infections Pneumocystis carinii Echinococcosis (hydatid disease)

Bacterial infections

Bacterial infections present as pneumonias or abscesses. Acute pneumonia and lung abscesses are characterized by a neutrophilic exudate. Many bacteria, but not all, can be seen with Routine stains as well as with Gram stain. A specific identification of Legionella pneumophila can be made in BAL samples by immunofluorescent antibody staining. Infection by Mycobacterium tuberculosis […]

Preneoplastic changes of respiratory epithelium

Squamous cell carcinoma of the lung is preceded by precursor lesions, with a progression from benign squamous metaplasia, through dysplasia, to invasive cancer. Most authors acknowledge degrees (mild, moderate, severe) of dysplasia. The risk of developing bronchogenic carcinoma increases with the degree of atypia. Preinvasive lesions Squamous dysplasia Carcinoma in situ Atypical adenomatous hyperplasia Diffuse […]

Lung cancer and other malignant tumours

Carcinoma of the lung is one of the most common malignancies in both men and women. It accounts for about 16% of all cancers diagnosed (20% of male and 12% of female cancers) making it the commonest malignancy and third most common cause of death in the UK. Its incidence has increased over the past […]

Viral infections

Herpes simplex thacheobronchitis and pneumonitis usually affect immunocompromised patients. Multinucleated cells are commonly seen, usually with eosinophilic, intranuclear inclusions. The dignosis can be confirmed by immunoperoxidase studies. Cytomegalovirus often causes an opportunistic infection, with diffuse pulmonary infiltrates. Viral changes, which are the same as in other sites, are seen in bronchial cells or pneumocytes: the […]

Reporting terminology

As with other non-gynaecologic cytologic specimens, respiratory tract diagnoses are reported as “negative for malignant cells”, “positive for malignant cells”, “suspicious for malignancy” (in this case a comment is required to state whether reactive or neoplastic changes are favoured) or “unsatisfactory (non-diagnostic)”, followed by a description.

Fungal infections

Pulmonary fungal infections are readily diagnosed by cytology; they often arise in immunocompromised patients. They should be always suspected whenever granulomatous inflammation is present, sometimes together with neutrophils. Cell blocks can be used for silver or periodic acid-Schiff (PAS) stains. Many fungi have a characteristic structure that enables a specific diagnosis. Several fungal infections can […]

Normal cells – Respiratory tract

cartilage in BW FNA negative – macrophages FNA negative – macrophages Transbronchial aspiration – benign Bronchial brush – benign bronchial epithelium Bronchial brush – benign bronchial epithelium  

Pneumocystis carinii

The pneumonia by Pneumocystis carinii is common in immunocompromised patients (such as HIV-positive), usually presenting as bilateral pulmonary infiltrates on radiographs. The organisms can be demonstrated in BAL material, as well as in bronchial washings and induced sputum. With Papanicolaou stains, masses of organisms enmeshed in a proteinaceous material can be observed as green, foamy […]