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 […]
Non-cellular elements and specimen contaminants
Non-cellular findings in respiratory material include those produced by the host, inhaled, formed as response to foreign material and introduced as laboratory contaminants. Curschmann`s spirals are coiled strand of mucus. On Papanicolaou stains, they appear as purple helices. They are a non-specific finding associated with chronic respiratory disorders. Ferruginous bodies are mineral fibers (such […]
Anatomy and histology of the respiratory tract
The respiratory tract can be divided into upper and lower compartments. The upper airway extends from the sino-nasal area to the larinx. The lower tract extends from trachea to the lungs and is the major focus of respiratory cytology. Cells of the upper airway are occasionally observed in the specimens from the lower tract. The […]
Indications of respiratory tract cytology
Compared with the remarkable success of the Pap smear in detecting and preventing cervical cancer, respiratory cytology (mostly sputum) has been a disappointment as a mass screening test for lung cancer. The problem is not lack of accuracy (sensitivity or specificity), but rather that even in high-risk patients (such as male smokers older than 45 […]
Cell sampling and preparation methods
Respiratory cytomorphology is heavily dependent on specimen type and preparation. Cell sampling and preparation methods are crucial for a correct cytologic interpretation. In the diagnosis of pulmonary nodules, bronchoscopic methods are usually the first approach for central lesions; if negative, fine needle aspiration (FNA) cytology can be performed. FNA cytology is particularly useful for peripheral […]
Sputum
Sputum consists of a mixture of cellular and non-cellular elements cleared by mucociliar apparatus. It is easy to obtain and cause little or no patient discomfort, but its use is declining because of the advent of bronchoscopy and fine needle aspiration. The sensitivity of sputum cytology for the diagnosis of malignancy increases with the number […]
Bronchial material
Bronchial material A great improvement in sampling cells from the lower respiratory tract occurred with the development of the flexible bronchoscope in the late 1960s. The complications of bronchoscopy, including laryngospasm, bronchospasm, disturbances of cardiac conduction and sepsis, are very rare. Bronchoscopic methods are particularly good for diagnosing central lesions, on which a biopsy and […]
Transbronchial fine needle aspiration (FNA)
Transbronchial FNA is especially useful for the diagnosis of primary lung lesions lying beneath the bronchial surface and for staging lung cancer patients with mediastinal lymphadenopaty. The lesion is aspirated by a retractable needle (Wang needle) that is passed through a flexible catheter sent down the bronchoscope. Complications of transbronchial FNA are rare, including endobronchial […]