Proteus genus

Question 1

General Features and habitat of Proteus mirabilis

Answer 1

Gram –

Rod shape

Habitat- normal intestinal flora (Enterobacteriaceae)

Highly Motile- peritrichous (many) flagella, demonstrate swarming when plated

Question 2

Biochemical Properties of Proteus mirabilis

Answer 2

Facultative anaerobe
Urease +
H2S +
Lactose non-fermenter (-)

Question 3

Pathogenesis of Proteus mirabilis

Answer 3

Nosocomial infection- from urinary catheters

Urease raises the urine pH causing kidney stones formation

Question 4

Clinical Features of Proteus mirabilis

Answer 4

Urinary Tract Infection (UTI)

Kidney stones are referred to as staghorn renal calculi for their shape

Sepsis- motility help it enter bladder, causing shock and fever by endotoxins

Question 5

Diagnosis of Proteus mirabilis

Answer 5

Agar plate (Gram staining)- fish odor with swarming appearance

EMB medium- produces pink colonies (lactose negative)

Urease test- shows purple color in tube (i.e. positive, like Helicobacter and Klebsiella)

Question 6

Treatment of Proteus mirabilis

Answer 6

Sulfonamides

Question 7

Other Proteus Species:

Answer 7

Proteus vulgaris, Proteus penneri

90% of infections are P. mirabilis