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CLINICAL LABORATORY DIAGNOSTICS OF PATHOLOGICAL PROCESSESS IN LUNGS. Marushchak Maria. Obtaining a sputum sample. Mouth should be free of foreign objects Remove food, gum, or Tobacco Remove dentures Early morning specimen is best Induce sputum if necessary
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CLINICAL LABORATORY DIAGNOSTICS OF PATHOLOGICAL PROCESSESS IN LUNGS Marushchak Maria
Obtaining a sputum sample • Mouth should be free of foreign objects • Remove food, gum, or Tobacco • Remove dentures • Early morning specimen is best • Induce sputum if necessary • Nebulized hypertonic saline or distilled water • Chest percussion • Postural drainage • Cough into sterile specimen cup
Special Circumstances • Tuberculosis suspected • Sputum collected in negative pressure room • Early morning gastric aspirate • Bronchoscopy with bronchial lavage • Anaerobic culture specimen • Transtracheal aspiration • Thoracentesis • Direct lung puncture • Viral Culture Specimens • Patient gargles and expectorates with nutrient broth • Nasopharyngeal swab transported in viral medium
Preparation of Sputum for Lab • Fixation of sputum for cytology (prevents air drying) • Patient expectorates into jar of 70% Ethanol • Spread fresh sputum on slide and spray pap fixative • Culture specimen transport to lab • Sputum Gram Stain assesses sample for adequacy • Anaerobic cultures transported in air tight container • Transport to lab for immediate plating • Aerobic culture specimen • Bring to lab as quickly as possible • Refrigerate specimen if transport delayed • Consider washing specimen of oral flora • Rinse several times with saline • Discard supernatant (non-viscous Saliva) • Tuberculosis culture • May be stored at room temperature for up to 48 hour
Diagnosis #1: Necrotizing granulomas, cervical lymph node, acid-fast organisms present. Non-necrotizing granulomas, pleura, no acid-fast organisms seen. • Cervical lymph node: A low-power view of the cervical lymph node shows necrotic nodules surrounded by a layer of pale histiocytes. Giant cells and non-necrotizing granulomas were absent. An acid-fast stain revealed beaded bacilli consistent with mycobacteria.
Pleural biopsy: Non-necrotizing granulomas with central, epithelioid cells and surrounding lymphoid cells are present. Giant cells are absent. No acid-fast organisms were found.
Estimate daily volume of Sputum • Small amounts • Lung Abscess • Pneumonia • Tuberculosis • Copious amounts (>200 cc/day) • Bronchiectasis • Bronchopleural Fistula
Sputum Color • Bloody Sputum (Hemoptysis) • Rusty Sputum (Prune-juice) • Pneumococcal Pneumonia • Purulent Sputum (yellow, green, dirty-gray) • Color alone does not distinguish bacterial infection
Sputum Turbidity • Frothy Sputum (air bubbles, Hemoglobin) • Pulmonary edema • Foamy, clear material • Saliva • Nasal secretions
Sputum Viscosity • Bloody Gelatinous Sputum (Currant-Jelly) • KlebsiellaPneumonia • Pneumococcal Pneumonia • Stringy Mucoid Sputum (may also appear frothy) • Follows Asthma exacerbation • Cloudy, mucoid Sputum • Chronic Bronchitis • Three layered appearance (stagnant, Purulent Sputum) • Bronchiectasis • Lung Abscess
Sputum with Feculent Odor • Anaerobic infection • Bronchiectasis
Example of case • A. An overall view shows a circumscribed, non-encapsulated mass of mature adipose tissue traversed by small vessels. It is covered by normal respiratory epithelium, which is separated from the fat by a loose fibrous stroma that contains a large number of lymphocytes and plasma cells. The hemoptysis that can occur with these lesions is caused by the pneumonia secondary to the tumor and not by the tumor itself.
B. At higher magnification, the subepithelial fibrous tissue is chronically inflamed. The irregular dark blue area is a lymphoid aggregate. The underlying fat and blood vessels blend in with the fibrous tissue rather than being sharply demarcated.
C. The subepithelial tissue has chronic inflammatory cells (lymphocytes (without visible cytoplasm) and plasma cells (with visible cytoplasm)).
What is the diagnosis? Endobronchial lipoma • D. At the edge of the lesion, loose connective tissue and fat are mixed together.
Assessing Sputum Sample Quality • Ideal Sputum Sample for Culture • Under 10 squamous epithelial cell per low power field • Many Neutrophils present (>5 per high power field) • Bronchial epithelial cells present • Alveolar Macrophages may be present • Inadequate Sputum Sample • Over 25 squamous epithelial cells/LPM
Sputum Sample Preparation • Pull strand or plug of Sputum onto slide • Consider buffered crystal violet to stain cells • Apply cover slip • View under oil immersion
Cytology Stains • No Stain • Blastomycosis • Cryptococcosis • Gram Stain • Gram Positive Bacteria • Candida • Tuberculosis (weakly Gram Positive) • Nocardia (weakly Gram Positive) • Direct Fluorescent Antibody Staining • Legionella • Wright stain or Giemsa Stain • Intracellular organisms
Acid-fast Mycobacteria (Tuberculosis) • Ziehl-Neelsen Stain (Red against blue background) • Kinyoun stain • Less reliable than Ziehl-Neelsen stain • Results in quickly stained sample • Fluorochrome dyes (auramine, rhodamine) • Higher false positive rate than Ziehl-Neelsen stain • Assist greatly in identifying organisms
Fungal Organisms • PAS staining or Methenamine silver staining • Histoplasmosis • Coccidioidomycosis • Aspergillus • Mucor • KOH Preparation
Microscopic findings • Caseous masses • Dittrich's plugs • Curschmann's spirals (Asthma) • Charcot-Leyden Crystals (Asthma) • Bronchial casts • Concretions • Broncholith • Calcified particles as seen in Broncholithiasis • Lung Cancer cells • Central bronchus tumors • May require 4 samples to detect • Eosinophils (>5%): identified with Wright's Stain • Allergy • Asthma