II. Indications: Sputum Examination in Community Acquired Pneumonia

  1. IDSA/ATS recommends Sputum sample obtained for inpatients before antibiotic therapy
    1. Absence of Gram Negative Rods and Staphylococcus aureus on a good quality Sputum Culture is reassuring
    2. Sputum Culture can help direct subsequent antibiotic therapy narrowing
  2. IDSA/ATS 2007 indications for Sputum Culture
    1. ICU Admission
    2. Failed outpatient antibiotic therapy
    3. Cavitary infiltrates
    4. Active Alcohol Abuse
    5. Severe COPD
    6. Pleural Effusion
    7. Positive Legionella urine Antigen (Legionella culture requires special media)
    8. Positive Pneumococcal urine Antigen
    9. Mandell (2007) Clin Infect Dis 44:S27–72 [PubMed]

III. Efficacy

IV. Technique: Assessing Sputum Sample Quality

  1. Ideal Sputum Sample for Culture
    1. Under 10 squamous epithelial cell per low power field
    2. Many Neutrophils present (>5 per high power field)
    3. Bronchial epithelial cells present
    4. Alveolar Macrophages may be present
  2. Inadequate Sputum Sample
    1. Over 25 squamous epithelial cells/LPM

V. Technique: Sputum Sample Preparation

  1. Pull strand or plug of Sputum onto slide
  2. Consider buffered crystal violet to stain cells
  3. Apply cover slip
  4. View under oil immersion

VI. Approach: Cytology Stains

  1. No Stain
    1. Blastomycosis
    2. Cryptococcosis
  2. Gram Stain
    1. Gram Positive Bacteria
    2. Candida
    3. Tuberculosis (weakly Gram Positive)
    4. Nocardia (weakly Gram Positive)
  3. Direct Fluorescent Antibody Staining
    1. Legionella
  4. Wright stain or Giemsa Stain
    1. Intracellular organisms

VII. Approach: Special Staining Circumstances

  1. Acid-fast Mycobacteria (Tuberculosis)
    1. Ziehl-Neelsen Stain (Red against blue background)
    2. Kinyoun stain
      1. Less reliable than Ziehl-Neelsen stain
      2. Results in quickly stained sample
    3. Fluorochrome dyes (auramine, rhodamine)
      1. Higher False Positive Rate than Ziehl-Neelsen stain
      2. Assist greatly in identifying organisms
  2. Fungal Organisms
    1. PAS staining or Methenamine silver staining
      1. Histoplasmosis
      2. Coccidioidomycosis
      3. Aspergillus
      4. Mucor
    2. KOH Preparation

VIII. Findings: Microscopic

  1. Caseous masses
  2. Dittrich's plugs
  3. Curschmann's spirals (Asthma)
  4. Charcot-Leyden Crystals (Asthma)
  5. Bronchial casts
  6. Concretions
  7. Broncholith
    1. Calcified particles as seen in Broncholithiasis
  8. Lung Cancer cells
    1. Central Bronchus tumors
    2. May require 4 samples to detect
  9. Eosinophils (>5%): identified with Wright's Stain
    1. Allergy
    2. Asthma

Images: Related links to external sites (from Bing)

Related Studies

Ontology: Sputum microscopy procedure (C0430395)

Concepts Laboratory Procedure (T059)
SnomedCT 269913005, 167995008, 145233002, 145224004
English Sputum microscopy NOS, Microscopic examination of sputum specimen, Sputum microscopy NOS (procedure), Sputum microscopy, Sputum microscopy (procedure), Sputum microscopy procedure
Spanish microscopia de esputo, SAI (procedimiento), Sputum microscopy NOS, microscopia de esputo, SAI, microscopia de esputo (procedimiento), examen microscópico de muestra de esputo, examen microscópico de muestra de esputo (procedimiento), microscopia de esputo

Ontology: Microbial culture of sputum (C0523174)

Concepts Laboratory Procedure (T059)
SnomedCT 145234008, 168005003, 104173009
Italian Coltura di espettorato
Japanese 喀痰培養, カッタンバイヨウ, カクタンバイヨウ
English Sputum culture, sputum culture (lab test), sputum culture, cultures sputum, culture sputum, Sputum culture (procedure), Sputum Culture, Microbial culture of sputum, Microbial culture of sputum (procedure)
Czech Kultivace sputa
Hungarian Köpet tenyészet
Spanish cultivo microbiano de esputo (procedimiento), cultivo microbiano de esputo, Cultivo de esputo
Portuguese Cultura de expectoração
Dutch sputumkweek
French Culture de crachat
German Sputumkultur

Ontology: Sputum cytology (finding) (C0551076)

Concepts Finding (T033)
SnomedCT 145669001, 168476005
Dutch sputum cytologie
French Cytologie de crachat
German Sputumzytologie
Italian Citologia dell'espettorato
Portuguese Citologia da expoctaração
Spanish Citología de esputo, citología del esputo (hallazgo), citología del esputo
Japanese 喀痰細胞診, カッタンサイボウシン, カクタンサイボウシン
Czech Cytologie sputa
English cytology sputum, Sputum cytology (procedure), Sputum cytology, sputum cytology, Sputum cytology (finding)
Hungarian Köpet cytologia