Medical Laboratory Videos: Introduction, List of Contents with Description

Introduction of Medical Laboratory Videos

The topic ‘Medical Laboratory Videos’ is a huge collection of author genuine works pertaining to medical laboratory science especially bacteriology, mycology, parasitology, virology, immunology/serology, molecular biology, hematology, biochemistry, blood banking, and transfusion medicine, histopathology, and phlebotomy.

List of Contents for Medical Laboratory Videos

1. Hanging Drop Preparation/Technique/ Method
2. Oxidase test
3. Semen analysis
4. Human Blood Cells Demonstration
5. Urine Microscopy of UTI Patient
6. Pus Culture and Sensitivity (C/S)
7. Cultured Human Parasites Microscopy
8. Live Trichomans vaginalis in HVS saline wet mount

Description

Hanging Drop Preparation/Technique/ Method

Hanging Drop preparation: It is a technique for observation of motility of bacteria which may either from the direct specimen ( diarrhoeal stool of cholera suspected for darting motility) or from laboratory manipulated method ( passing isolated colony into peptone water).

This is a simple and also called agar technique where there is no need for cavity slide and adhesive or paraffin wax. The clip is without audio but step by step visual demonstration and if there is any confusion, do not hesitate to write in the comment box.

Oxidase Test

Oxidase Test: It is the most common test used in microbiology laboratories for the presumptive identification of various bacterial isolates. In the presence of atmospheric oxygen, an organism’s intra-cellular cytochrome oxidase enzymes oxidize the N, N, N, N-tetramethyl-p phenylenediamine dihydrochloride (substrate) to indophenol, a dark purple-colored end product. This oxidase test is useful in the primary characterization of gram-negative bacteria. Pseudomonas aeruginosa is oxidse positive while Escherichia coli negative.

List of oxidase-positive bacteria-

• Pseudomonas spp. (except Ps. cepacia)
• Aeromonas spp.
• Vibrio spp.
• Brucella spp. (except B. canis)
• Haemophilus spp.
• Alcaligenes spp.
• Campylobacter spp.
• Plesiomonas spp.
• Chromobacterium spp.
• Bordetella spp. (Except-B. parapertusis)
• Flavobacterium spp.
• Achromobacter spp.
• Pasteurella multicida
• Eikinella spp.
• Cardiobacterium spp.
• Eikinella spp.

Gram-negative cocci-

• Neisseria spp.
• Moraxella spp.

Note: Micrococcus species are modified oxidase-positive

Semen Analysis

Semen analysis: It is a test of a man’s sperm and semen and is also called a sperm count or male fertility assay, its finding represents how many sperm are released, as well as how they’re shaped and how well they move. In this assay, abnormal cells, as well as the presence of microbes, are also monitored. Semen is the thick fluid that falls from men’s penis when they ejaculate during sexual intercourse or masturbation. Normal sperm count, shape, motility, and infection-free are crucial factors for male fertility.

Human Blood Cells Demonstration

Our blood cells on Peripheral Blood Smear (PBS) Microscopy: In this subheading, you will become able to see blood cells of our body i.e. red blood cells/corpuscles, platelets, and white blood cells (leukocytes) and its subtypes like polymorphonuclear (PMN) leukocytes/ neutrophil, eosinophil, lymphocyte, and monocyte. The creator could not show basophil in this video clip due to the occasional occurrence in normal PBS microscopy.

Urine Microscopy of UTI Patient

A suspected patient of urinary tract infection (UTI) urine under the microscope at high magnification is showing plenty of pus cells (dead leukocytes mostly neutrophils), a few epithelial and red blood cells (RBCs). There is also plenty of bacteria trapped inside the pus cells (observe carefully in the video clip of the high magnification portion).

Pus Culture and Sensitivity (C/S)

Pus Culture and Sensitivity (C/S): It is the most common assay in the Microbiology laboratory to find out the etiological agents responsible for pus formation. As you know, the pus specimen is sterile if there is any microbe presence which is the causative agent and this is the reason during sample collection where there is the involvement of normal flora, collect specimen properly omitting the flora otherwise false positive report will be generated.

Gram stain is mandatory in our scenario of pus c/s since we do not proceed with anaerobic culture and fungal culture and so there is a chance of escaping of microorganisms (obligate anaerobes, fungi other than Candida, Cryptococcus, parasites depending on nature of pus e.g. Entamoeba histolytica of amoebic liver abscess (ALA) occasional footage, viral involvement-multinucleated giant cells indicator of Herpes simplex and herpes zoster). Below video clip is regarding ‘Pus Culture and Sensitivity’ where you well get pus sample in a syringe, Gram stain finding footage, media used for culture, biochemical tests used ( coagulase test, use of mannitol salt agar) for identification of isolate (Staphylococcus aureus) and antibiogram pattern (antimicrobial susceptibility testing/AST).

Cultured Human Parasites Microscopy

Cultured Human Parasites Microscopy: In this section, the author will show live larvae of parasites (Strongyloides stercoralis). This parasite was found during stool routine examination microscopy and it was cultivated on Muller-Hinton agar (MHA) and stored the inoculated stool/feces specimen MHA plate at room temperature for 3 days. The agar plate was also sealed with paraffin sealing film from escaping the parasites. Now the MHA plate is on the microscope for observation of parasites at various magnifications. Just join the visual demo and enjoy.

Live Trichomonas vaginalis in HVS Saline Wet Mount

Live Trichomonas vaginalis in HVS saline wet mount: An obstetrician/gynecologist sent a high vaginal swab (HVS) from a patient having vaginal discharge to the microbiology section to find the clinical condition of vaginal thrush or bacterial vaginosis or trichomoniasis for microscopy and culture and sensitivity. The author found during saline wet mount microscopy various trophozoites of Trichomonas, plenty of pus cells, epithelial cells, and occasional RBCs. No pathogen was isolated in culture and Trichomonas was only responsible for this situation. Now join the visual demo at various magnifications.

Urine Culture and Sensitivity Procedure and Result Interpretation

Urine Culture and Sensitivity (C/S): It is the most common test ordered by clinicians in Microbiology and it is useful to grow and identify organisms, mainly bacteria, and fungi( Candida) that may cause a Urinary Tract Infection (UTI). Bladder urine is normally sterile and UTIs are more common in females (due to close vagina and urethra) and children (immunocompromised) than in adult males. The antimicrobial susceptibility (AST)  helps to select an appropriate antimicrobial agent that is effective against specific types of microbe (bacteria or fungi) causing any infection. The author is dunking a video clip regarding the procedure of urine culture and sensitivity.

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