UTI stands for urinary tract infection. The document discusses UTI, including that it is caused by microbes inflaming the urinary tract lining. It can be lower or upper, acute or chronic, primary or secondary. Urine culture is the gold standard for diagnosis. UTI can lead to complications if mismanaged or treatment is delayed. The pathogenesis involves routes of infection like ascending or hematogenous. Host defenses interact with pathogen virulence factors like adherence structures or resistance to killing. Specific etiologies are linked to risk groups. Renal stones can also be associated with recurrent UTIs. Urine culture results are used to interpret infection levels.

1. UTI
DR.HAMISI MKINDI,MD.
TO DOWNLOAD CONTACT: hermyc@live.com

2. Overview
• UTI is an inflammation of the epithelial lining the urinary
tract caused by microbes
Lower vs Upper
Acute vs Chronic
Primary vs Secondary
Etiology based classification
• Urine culture remains a gold standard in diagnosis
• UTI can result into complications following
mismanagement or delayed management

3. Pathogenesis
• Route of infections : ascending mostly, but also
hematogenous and lymphogenous
• Host defensive mechanisms vs Pathogen’s virulence
factors
Host Defensive factors Pathogens’ virulence factors
Physical & Mechanical Adherence – pilli /fimbriae
Chemical Resistance to serum bactericidal activity –
capsule (K- antigen )
Immunological (innate & acquired) Enzymes – hemolysins, cytolysins, urease,
etc…
Biological LPS and O, K & H antigens in gram negative
enteric bacteria (uropathogenic serotypes)

4. Etiology specific to a particular risk groups

6. Renal stones & UTI
Pathogenesis is multifactorial and complex
Heredity
Geographical
location
Diet
Drugs
Recurrent UTIs due to Proteus spp

7. Tanzania Journal of Health Research, Vol. 11, No. 3, July 2009

8. Culture
No. of colonies on plate
(using 1 µl) loop
Corresponding
CFU/ml
Interpretation
1 - 9 103 Indicates possible contamination
10 - 99 104 Possible infection or contamination
≥ 100 105 Infection