AFB staining - Allied Guru

Table of Contents

Principle

AFB staining ka principle Mycobacterium bacteria ke cell walls ki unique properties pe based hai.
In bacteria ke cell walls mein high concentration hoti hai mycolic acids ki, jo unko zyada dye se resist karne ki ability deti hai.
AFB staining method ek powerful red dye, carbolfuchsin, ka use karta hai, jo bacteria ke cell wall mein penetrate kar jaata hai.
Jab yeh dye andar chali jaati hai, toh thick lipid layer ki wajah se woh dye bacteria ke andar trapped ho jaati hai, aur acid-alcohol se decolorize hone ke baad bhi yeh bacteria red hi rehte hain.
Is resistance ki wajah se acid-fast bacteria microscope mein clearly dikhte hain, jabki dusre bacteria decolorize ho jaate hain.

Microscope: Ek compound light microscope with oil immersion lens (100x) taaki acid-fast bacilli clearly dekh sakein.
Glass slides: Clean slides jahan bacterial smear prepare kiya jaa sake.
Heat source: Smear ko fix karne ke liye aur dye penetration mein madad karne ke liye.
Inoculating loop: Bacterial sample ko slide par transfer karne ke liye.
Staining rack: Slides ko staining process ke dauran rakhne ke liye.

Carbolfuchsin (Primary stain): Yeh powerful red dye bacteria ke cell wall ko stain karti hai.
Acid-alcohol (Decolorizer): Alcohol aur hydrochloric acid ka mixture jo non-acid-fast bacteria se dye hata deta hai, lekin acid-fast bacteria par effect nahi karta.
Methylene blue (Counterstain): Yeh blue color deta hai non-acid-fast cells ko aur background ko, jo ki acid-fast bacteria ko asani se alag karne mein madad karta hai.

Clinical Specimens: Sputum, urine, blood, cerebrospinal fluid, aur tissue biopsies yeh sab samples use hote hain jab kisi ko tuberculosis ya dusre mycobacterial infections hone ka shak hota hai.
Smear Preparation: Sample ka ek chhota amount glass slide par transfer karke, smear ko air-dry karte hain aur heat-fix karte hain taaki bacteria slide par properly stick ho jayein.

Smear prepare karein: Clinical specimen ka ek chhota drop lekar slide par evenly spread kar lein. Uske baad smear ko air-dry karne dein aur phir slide ko flame ke upar pass kar ke heat-fix kar lein.
Carbolfuchsin stain apply karein: Smear par carbolfuchsin ke kuch drops dalke, slide ko gently heat karein (5 minutes tak). Yeh ensure karega ki dye bacteria ke waxy walls ko penetrate kar jaaye.
Decolorization karein: Slide ko thoda thanda karne ke baad, excess dye ko wash off karne ke liye water se rinse karein. Fir acid-alcohol apply karein (1-2 minutes ke liye). Isse non-acid-fast bacteria se red dye remove ho jaayegi, lekin acid-fast bacteria red hi rahenge.
Methylene blue se counterstain karein: Slide ko phir water se rinse karein aur methylene blue apply karein (1-2 minutes ke liye). Yeh non-acid-fast cells aur background ko blue color dega.
Rinse, dry aur examine karein: Excess counterstain ko rinse karne ke baad, slide ko gently blot karein aur phir air-dry karne dein. Uske baad microscope se examine karein.
Examine karein under the microscope: Oil immersion lens ka use karke slide ko dekhein. Acid-fast bacilli red ya pink rang mein dikhai denge, jabki non-acid-fast cells blue dikhai denge.

Acid-Fast Bacilli (AFB): Yeh bacteria bright red ya pink dikhai denge, jo carbolfuchsin stain ko retain karte hain acid-alcohol treatment ke baad.
Non-Acid-Fast Cells: Yeh cells blue dikhai denge, kyunki inhone carbolfuchsin stain kho diya hai aur methylene blue counterstain retain kiya hai.

Tuberculosis (TB) Diagnosis: AFB staining Mycobacterium tuberculosis ko detect karne ke liye ek effective method hai, jo sputum samples mein milta hai, taaki TB ka diagnosis jaldi aur accurately kiya ja sake.
Leprosy Ki Pehchaan: AFB staining Mycobacterium leprae ko skin biopsies aur nasal secretions mein detect karne ke liye use hoti hai, jo leprosy ke diagnosis mein madad karti hai.
Dusre Mycobacterial Infections: Yeh technique dusre mycobacteria ko bhi identify karti hai, jaise Mycobacterium avium aur Mycobacterium intracellulare, jo immunocompromised patients mein infections cause karte hain.
Environmental Testing: AFB staining ko water aur soil mein mycobacteria detect karne ke liye bhi use kiya jaata hai, taaki environmental contamination ko rokha ja sake.
Research Aur Surveillance: Scientific research mein AFB staining Mycobacterium species ke structure aur behavior ko study karne mein madad karti hai, jo treatment aur vaccine development mein useful hota hai.