Clinical Microbiology and Infectious Diseases

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What does a cloudy or turbid cerebrospinal fluid (CSF) specimen indicate?

Increased pressure in the cranial cavity

Presence of white blood cells (correct)

Presence of a bacterial infection

Decreased glucose levels

Which of the following indicates a normal cerebrospinal fluid (CSF) sample?

Crystal clear appearance (correct)

High protein concentration

Cloudy appearance

Presence of white blood cells

Why is a lumbar puncture contraindicated when there is increased intracranial pressure?

It may introduce infections.

It can cause herniation through the foramen magnum. (correct)

It can lead to excessive bleeding.

The patient may become unresponsive.

What could be inferred from a cerebrospinal fluid (CSF) sample showing an increased protein concentration?

Underlying neurological disorder Signup and view all the answers

Which type of specimen collection method is recommended for cerebrospinal fluid analysis?

Collection by a trained physician using strict surgical asepsis. Signup and view all the answers

Which characteristic does NOT indicate a normal cerebrospinal fluid (CSF) analysis?

Presence of lipids Signup and view all the answers

What is one possible clinical significance of finding elevated levels of white blood cells in a cerebrospinal fluid (CSF) sample?

Sign of viral or bacterial infection Signup and view all the answers

What is the purpose of labeling the three sterile tubes during cerebrospinal fluid collection?

To differentiate between samples for chemistry, microbiology, and hematology. Signup and view all the answers

Which of the following bacteria is included in the HACEK group?

Eikenella corrodens Signup and view all the answers

Which component of cerebrospinal fluid collection tubes is used for microbiology analysis?

Tube designated for microbiological culture. Signup and view all the answers

What is a key characteristic of cerebrospinal fluid (CSF) in cases of aseptic meningitis?

Negative culture with increased cell count Signup and view all the answers

In aseptic meningitis, if a child shows symptoms lasting more than one week, which organism is most likely responsible?

Mycobacterium tuberculosis (MTB) Signup and view all the answers

Which of the following statements about aseptic meningitis is true?

Viruses are the most likely causative agents with short duration symptoms. Signup and view all the answers

What commonly affects the analysis of cerebrospinal fluid in suspected aseptic meningitis?

Negative culture results Signup and view all the answers

What symptom duration suggests that a child’s illness may involve Mycobacterium tuberculosis in aseptic meningitis?

More than 1 week Signup and view all the answers

Study Notes

Diagnosing Infectious Diseases

Pathology Department Organization:
- Anatomical Pathology (Electron Microscopy, Morgue/Autopsy, Histopathology, Cytology Lab, Cytogenetics Lab)
- Clinical Pathology (Clinical Microbiology, Clinical Immunology, Hematology, Hematopathology, Blood Transfusion Bank, Clinical Chemistry)
- Bacteriology (part of CML in larger hospitals, but sent to reference labs in smaller hospitals)
- Mycobacteriology (part of CML in larger hospitals, but sent to reference labs in smaller hospitals)
- Virology (part of CML in larger hospitals, but sent to reference labs in smaller hospitals)
- Immunology (independent in larger hospitals, part of CML in smaller hospitals)
- Mycology
- Parasitology

Clinical Microbiology Lab (CML)

Mission: Active participation in managing patients with infectious diseases.
Responsibilities:
- Processing clinical specimens
- Isolating potential pathogens
- Identifying isolated pathogens
- Antibiotic sensitivity testing (AST)
- Hospital outbreak recognition and source identification (environmental samples, healthcare worker screening)

Clinical Specimens

Collection:
- Collected from patients to diagnose or monitor infectious diseases.
- Components for High-Quality Specimens:
  - Proper specimen selection
  - Correct techniques for collection (detailed instructions to patient, standard precautions, pre-antimicrobial therapy, sufficient quantity, sterile container, proper labeling)

Processing Clinical Specimens

Specimen Type Variations:
Macroscopic Examination/Naked-Eye:
Microscopic Examination: (wet mount/staining) - direct examination, on specimens' what could be seen, or on next day's isolated colonies.
Culture Media Inoculation: appropriate culture media→pure growth
Identification & AST(Antibiotic Sensitivity Test): directly on specimens or on next day's isolated colonies

Additional Notes

Urine Specimen Collection:
- Clean catch mid-stream
- Catheterized specimens
- Urine bags (babies)
- Suprapubic needle aspiration (SPA)
Urine Processing Time: within 30 minutes of collection or 24 hours refrigerated
Specimen Rejection Criteria: Leaked containers, insufficient quantity (QNS), specimens sent in formalin.
Specimen Transport: As soon as possible (no delay); properly stored.
Specimen Processing: vary according to the type of specimen.
Quantitative Bacterial Colony Count: Colony-forming units (CFU) are used to determine the number of viable bacteria per mL of urine. Factors like calibrated loops and dilution influence the CFU calculation.
Results/Interpretation: Criteria to determine clinical significance include patient's details, specimen type, growth patterns, and pathogen counts.

Additional Topics

Blood Culture Specimens: aseptic technique used with precautions.
Cerebrospinal Fluid (CSF): CSF collection and processing (include macroscopic and microscopic examination).
Wound Specimens: preferable ASPIRATE (syringe) technique.
Feces/Stool Specimen Collection: Collect stool sample using clean (unsterile) container, add preservative, prompt transport to lab, and process within 2 hours. Includes microbial pathogens like Salmonella and Shigella.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Explore the intricate processes and responsibilities within the Clinical Microbiology Lab (CML) as it relates to diagnosing infectious diseases. This quiz covers various aspects of pathology organization, including microbiology, immunology, and the handling of clinical specimens. Test your knowledge on the essential roles these departments play in patient management.