1. Urinary tract infection due to Escherichia coli
Urinary tract infection due to Escherichia coli. The urinary bladder, perineal mucosa, and short female urethra are shown. E coli from the nearby rectal flora have colonized the perineum, utilizing binding by type 1 (common) pili. E coli with P pili are also present but are of no use at this site. A. A few E coli have gained access to the bladder owing to mechanical disruptions such as sexual intercourse or instrumentation (catheters). Note that receptors for the P pili not present on the perineal mucosa are found on the surface of bladder mucosal cells. B. During voiding, the bladder has expelled the E coli, which have only type 1 pili. The P pili-containing bacteria remain behind due to the strong binding to the P (Gal–Gal) receptor. C. The remaining E coli have multiplied and are causing a UTI (cystitis) with inflammation and hemorrhage. In some cases, the bacteria ascend the ureter to cause pyelonephritis in the kidney where the P (Gal–Gal) receptor is most abundant. WBCs, white blood cells.
Source: Pathogenic Bacteria, Sherris Medical Microbiology, 6e
Citation: Ryan KJ, Ray C. Sherris Medical Microbiology, 6e; 2014 Available at: Accessed: January 10, 2018
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