University:
Swansea University
Course:
PM134 | Microbiology
Academic year:

2023
Views:

77

Pages:

3
Author:

Yasin N.

Laboratory Diagnosis SPECIMEN Collection PLOOD 300 1st weeklag) *Clot all bure Bleed in -Culter wndiem- Menephaesit or Biphasic (commeds) On Bleed ager Nor bearbetse mort dones InMarlenkey ayors Pound women, Stoland Wine Cultues #3rd & 4th week -Enrichment broth gente froth wilson Phir - Bellait green Bismuth. sulfite ardeon 3. Typhi Jet Hach coloud iclonics with metallic sheen. 5. pratyphus pale enter / No color change amonstrations of Scrum Antibodies Molecular methods FPCR WIDAL TEST Houd Abs are detested by any de TO Contiger of stypl THA Η antiger Gran LAB DIAGNDSS of INTERK FEVER Demonstration of serum Antigac Henr (verdeatthu) HELISA Hangtinshen Lorige leeres thilly cetten. welly chrips fale positive Ameztse respere Fake negelthes forty (letsarth) I other epecimens Slide Aglutachon kst Identifiration of Calmonells at geure level wing pelyvalent O antisera 4 methods 1. Specimen collection 2. Demonstration of serum Antibodies 3. Demonstration of serum Antigens 4. Molecular methods SPECIMEN CULTURE Blood culture and serology Stool culture Urine culture Ideal specimen of collection If the patient comes within first week Blood culture followed by fecal culture If the patient comes after a week within 10 days Blood serology preferred followed by feces culture Widal test (O and H antigens) Diagnosis of Enteric fever Widal test Bone marrow 90% Urine culture 25% Urine culture 10% Feces culture 80% Feces culture 50% Blood culture 80 to 90% 2 Weeks Decreasing positivity abpeha net MNEMONIC-BASU B-Blood culture - 1st week A- Agglutination (WIDAL) -2nd week S-Stool-4th week U-Urine-3rd week WIDAL test Titer - The cut-off of titer varies from place to place, in western countries 1/20 itself is taken as positive whereas in endemic countries like India: H agglutinin titer more than 200 : O agglutinin titer more than 100 This is because due to prior exposure people will always have some baseline antibodies! NOTE: In culture media selective media used:- 1. Low selective media MacConkey Agar 2. Highly selective media - DCA agar (NLF colonies with black centre) & XLD Agar (red colonies with black centre) & Wilson Blair's method (already described in pic) DETECTION OF CARRIERS: Done by detection of Vi antibodies; even a titer 1:10 is considered significant but confirmation must be made by culture