Recording-2025-03-24T23:32:09.537Z

Overview of Microbiology

• Microbiology: The study of microorganisms, which are simple forms of microscopic life.

• Types of Microorganisms:

  • Resident Normal Flora: Microorganisms that reside on skin and within the body without causing disease. Examples include intestinal flora that aid in digestion and protect against infections.

  • Pathogens: Microorganisms capable of causing disease.

Role of Intestinal Flora

• Digestive Aid: Intestinal flora help break down food, turning it into usable energy and absorbing essential nutrients.

• Protective Function: They act as a barrier against infections by competing with pathogenic microorganisms.

Pathogens and Disease Mechanisms

• Pathogens can cause disease through various mechanisms:

  • Consuming nutrients from host cells.

  • Damaging host cells by multiplying within them.

  • Inducing the host’s immune system to attack itself.

  • Producing toxins that harm the host.

Classification of Microorganisms

• Subcellular Microorganisms (Viruses): Extremely small, cannot be viewed under a regular microscope. Major bloodborne pathogens include HIV and hepatitis.

• Prokaryotic Microorganisms (Bacteria): Simple cells without a nucleus.

• Eukaryotic Microorganisms: More complex, including fungi, protozoans, and parasites.

Viral Infections – HIV and Hepatitis

• HIV:

  • Virus infecting/harming immune system's T cells.

  • Stages: Acute HIV, Chronic HIV, AIDS.

  • Symptoms include respiratory issues and skin lesions (e.g., hairy leukoplakia).

• Hepatitis:

  • Viral infection of the liver (most common: Hep B).

  • Symptoms include jaundice (yellowing of skin/eyes).

  • Vaccination is critical for prevention.

Bacteria as Pathogens

• Rapid reproduction makes bacteria a major cause of illness.

• Classification Factors:

  • Shape (e.g., cocci, bacilli, spirilla, vibrios).

  • Staining properties (Gram-positive vs. Gram-negative).

  • Oxygen requirement (aerobic vs. anaerobic).

  • Biochemical reactions (how bacteria metabolize nutrients).

• Drug-Resistant Bacteria: Examples include MRSA (methicillin-resistant Staphylococcus aureus).

Antibiotic Resistance

• Caused by overuse and misuse of antibiotics.

• Patients must be educated on the importance of completing prescribed antibiotic regimens to prevent resident bacteria from developing resistance.

Fungi and Parasites

• Fungi:

  • Reproduce via budding and include molds and yeasts.

  • Some cause infections like athlete's foot and yeast infections.

• Parasites:

  • Organisms relying on hosts for survival.

  • Infestations (e.g., worms) more common in developing countries.

  • Examples include roundworm and pinworm infections.

Diagnosing Infections

• Begins with patient evaluation, followed by specimen collection and culture testing to identify pathogens and determine antibiotic susceptibility.

• Importance of proper specimen collection:

  • Specimens must be obtained from infected areas (e.g., urine for UTIs, throat swabs for strep). Ensure labeling includes patient information, specimen type, date, and provider.

Culture Testing Guidelines

• Use proper collection containers and techniques to prevent contamination.

• Refrigerate specimens if not tested immediately to inhibit bacterial growth.

• Pay attention to PPE when handling sputum or wound specimens.

Transportation of Specimens

• Follow strict regulations for sending specimens to labs.

• Use biohazard labels to indicate potentially infectious materials.

• Specimens requiring refrigeration must be transported accordingly (often in coolers).

Conclusion

• Continuously educate patients about proper antibiotic usage and the importance of completing prescribed treatments. This reduces the risk of developing drug-resistant pathogens.