Lab diagnosis of proteus

Specimens

Pus, exudate, urine

Gram staining

Proteus are gram negative coccobacilli occasionally appear bacillary and in filamentous form.

Culture

Fishy odor

Swarming motility

Biochemical tests ( klebsiella to e coli )

Indole : Negative

Citrate: Variable

Urease Positive

TSI: alkaline/acid, gas present and H2S present

MR: Positive

VP: Negative

Proteus mirabilis and P. vulgaris can be differentiated by:

Indole test: Positive (P. vulgaris) , negative (P. mirabilis)

Ornithine decarboxylase test: Positive (P. mirabilis), negative (P. vulgaris)

Typing of Proteus

Bacteriocin typing:

• It is antibiotic like substance produced by one bacteria that inhibits other strains of bacteria,

Bacteriophage typing:

• Based on susceptibility to bacteriophage.

Ribotyping:

• It is molecular technique based on ribosomal RNA.

Dienes phenomena

Dienes phenomena

When two strains of Proteus are inoculated at different areas on a culture plate:

• ›If swarming of two strains merge incompletely, and remain separatby a narrow line of demarcation- indicates two strains are different.

• ›If swarming of two strains merge completely without any line ofdemarcation-indicates two strains are identical.