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- Purpose of the Gram Stained Direct Smear
- Reading and Reporting Direct Smears
- Gram Stain Principle
- Quality Control Smears
- Macroscopic Evaluation of the Smear
- Thick Smears
- Thin Smears
- Properly Decolorized Smears
- Under-decolorized or Over-decolorized Smears
- Reporting Microscopic Findings
- Contaminated Gram Stain Solution
- Summary of Gram Stain Reading and Reporting Procedure
- What color is the background material in a Gram-stained smear that has been adequately decolorized?
- What is the minimum number of fields that should be examined before reporting a Gram stained direct smear?
- If a smear is over-decolorized, it can be salvaged by repeating the Gram staining procedure.
- What is the purpose of the iodine that is used in the Gram stain procedure?
- Which of the following statements is true regarding the Gram-stained smear that is represented by this image?
- Bacteria in Direct Smears
- Gram-positive Cocci
- Gram-positive Diplococci
- Gram-negative Cocci
- Intracellular Bacteria
- Gram-negative Diplococci
- Special Considerations for Genital Smears
- Gram-positive Bacilli
- Gram-negative Bacilli
- Significance of Specific Findings
- The bacteria in this slide are gram-negative cocci.
- What are the structures indicated by the arrows in this field from a Gram stained smear?
- The presence of intracellular gram-negative diplococci on a smear made from a purulent urethral discharge from a male is diagnostic for gonorrhea.
- Nonbacterial Cells in Direct Smears
- Size and Appearance of Nonbacterial Cellular Elements on Gram Stained Smears
- Match the Gram stain reaction for each of the following nonbacterial elements.
- Which of the following cells are about the same size as red blood cells?
- What nonbacterial structures are present in this microscopic field of a Gram stained smear?
- This Gram stain was prepared from a sputum specimen and is viewed under oil immersion (1000x). What is the structure that is indicated by the arrow?
Level of Instruction: Basic
Intended Audience: This course is suitable for basic clinical microbiology courses at the post-secondary level. It can also be used as review material for clinical laboratory practitioners, medical students, and pathology residents. It requires skill in the use of the microscope, aseptic techniques, experience preparing and Gram staining smears, and experience reading smears from cultures.
Author Credentials: This course was developed by Betty Smith MT (ASCP) and Jaimy Hill MT (ASCP), and was updated by Education Materials for Health Professionals, Inc., under the supervision of Marjorie Spahn MT(ASCP). It was reviewed and adapted for online use by Paul Fekete, M.D. fellow C.A.P.
Reviewer Credentials: Dr. Julie Ann West is certified by the American Society for Clinical Pathology (ASCP) as a Medical Laboratory Scientist (MLS) and as a Specialist in Microbiology (SM). In addition, Dr. West has earned a PhD in Public Health - Infectious Disease Epidemiology and is Certified in Public Health (CPH) by the National Board of Public Health Examiners. Dr. West is experienced as a Technical Specialist, Safety Officer, Educator, and Lead in the Veterans Administration Healthcare System, and has prior experience as an Administrative Laboratory Director.
Copyright: Copyright EMHP Inc., Dayton OH. Licensed to MediaLab Inc., Lawrenceville, GA. Web-based version produced solely by MediaLab Inc.
Course Description: This course describes the morphology and Gram stain reactions of bacteria and nonbacterial elements found in Gram stained smears of clinical material.