Urinalysis - The Carter Center

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BACTERIA
Bacteria are the most common cause of UTI and aerobic gram-negative
bacilli, particularly, members of the enterobacteriacea, are the most
dominant agents. The Gram-positives account for proportionately large
number of infections in hospital inpatients. Normally, bacteria are not
seen in the healthy individual’s urine.
To check the presence or absence of bacteria a technician can either
check for Nitrate that was formed in the urine after breakdown of nitrite
into nitrate by the metabolic action of bacteria. Hence, dipstick test can
give indirect clue. Or one can use urine microscopy test to check the
presence of pus cells within the drop of urine or its sediment. Further
the observed bacterial cell can be identified by bacteriological culture.
Appearance
- Bacteria that are seen in the microscopic examination of the drop
of urine sample. Their shape varies with the type of bacteria
observed..
- Depending on the type of bacteria they can be either motile or non
motile organisms.
- They can be observed when examined under less than 40 x
(high power) objective of the microscope.
Clinical Significance
- Presence of bacteria may indicate the presence of UTI or
contamination by genital or intestinal microflora.
- To confirm what type of bacteria they are and whether or not they
are the causes of the disease, it is important to culture them in
appropriate media and perform biochemical tests for identification.