BORDETELLA(WHOOPING COUGH)

KING OF COUGH!!!

G.HARIPRASAD M.Sc.,(Med micro),M.phil.,Lecturer in Microbiology Department of Microbiology Thoothukudi Govt. Medical College Thoothukudi

GENERAL FEATURES:

• GRAM NEGATIVE SMALL, OVOID COCCOBACILLI.

• FORMS THUMB PRINT APPEARANCE ON NUTRIENT AGAR.

• COLONIES RESEMBLES “BISECTED PEARLS” OR “MERCURY DROPS” APPEARANCE.

VIRULENCE FACTORS:

• AGGLUTINOGEN• PERTUSIIS TOXIN (PT)• FILAMENTOUS

HEMAGGLUTININ• ADENYLATE CYCLASE• HEAT LABILE TOXIN• TRACHEAL CYTOTOXIN• LIPOPOLYSACCHARIDE.

PERTUSSIS TOXIN

PATHOGENESIS

• STAGE 1: CATARRHAL STAGE – INSIDIOUS ONSET

WITH LOW GRADE FEVER WITH DRY IRRITATING COUGH.

• STAGE 2: PAROXYSMAL STAGE – VIOLENT SPASMS

OF CONTINOUS COUGHING FOLLOWED BY A LONG INRUSH OF AIR INTO THE EMPTY LUNGS WITH A CHARACTERISTIC WHOOP.

• STAGE 3: CONVALESCENCE – FREQUENCY AND

SEVERITY OF COUGHING GRADULALLY DECREASE.

Entry through inhalation of droplet nuclei.

LABORATORY DIAGNOSIS

• SPECIMEN: Throat swab & sputum.• CULTURE: Bordet–Gengou Medium Charcoal agar • SEROLOGY: Agglutination

Immunofluroscence ELISA

CHARCOAL AGAR

BORDET-GENGOU MEDIUM

Pertussis toxoid – PTCombined toxoid – DPT

Erythromycin, Chloramphenicol, Cotrimoxazole Ampicillin.

TREATMENT

PROPHYLAXIS