Q: What is UTI( Urinary tract infection) ? What are the causes of UTI? How can you diagnose a case of UTI?

Q: What is UTI? What are the causes of UTI? How can you diagnose a case of UTI? 

Ans: Definition (UTI): Infection of the urinary tract by pathogenic organism is called urinary tract infection (UTI).

Causes of UTI:

Pathogenic Organism:

1.Bacteria	Gram negative E.coli (90% UTI) Proteus Enterobacter Pseudomonas Gram Positive Staph.saprophyticus(in female) Staph.Faecalis
2.Fungus	Candida albicans
3.Parasites	T.Vaginalis Schistosoma haematobium

Clinical Features:

a)      Dysuria: Burning sensation during micturation.

b)      Frequency of micturation.

c)      Urgency of micturation.

d)      Sometimes may be associated with pain in loin which radiates to groin.

e)      Fever, Anorexia.

Factors of UTI:

a)      Enlarged prostate.

b)      Calculi in urinary tract.

c)      Pregnancy.

d)      Female is more affected than male due to shortness of urethra.

 Lab diagnosis:

Specimen: First morning midstream urine.

Microscopic exam: 10 ml of urine is certrifuged.One drop of deposit is collected on glass slide, covered with cover slip & examined under light microscope. In case of UTI, pus cell & RBC are mainly looked for.

Findings: In case of UTI, pus cells will more than 5 high power fields.

Culture: Quantitative culture is done for UTI. A measured amount of urine is inoculated on appropriate media for colony

Count per ml of urine.

Media Used:

       Mac.Conkey’s agar.

       Blood agar.

Incubation temp: 37’ C

Incubation period: 18-24 hrs

Identification: The bacteria is identified by colony morphology, gm Staining, biochemical test of bacteria & confirmation of species by antiserum.

Colony count: Measured amount of urine is to be inoculated for colony count.eg; A wire loop of 2 mm of diameter contains 0.02 ml Of urine. The next day colony is counted & reported in per ml of urine.

Finding: The no. of colony is reported per ml of urine.

Colony count 1X 10’5 or above/ml of urine signifies UTI.

Colony count 1X 10’3 or less/ml of urine signifies UTI.