Complicated Urinary Tract Infections in Females

Definition and Anatomical Factors

A complicated urinary tract infection (UTI) in a female is defined as a UTI occurring in a patient with underlying structural or functional abnormalities of the urinary tract or with relevant comorbidities that increase the risk of treatment failure or serious complications 1, 2
Structural abnormalities, including cystoceles, bladder or urethral diverticula, fistulae, urinary tract obstruction, can make a UTI complicated 1, 2
Presence of indwelling catheters or other foreign bodies can also complicate a UTI 2
High post-void residual urine volumes, particularly in postmenopausal women, can contribute to complicated UTIs 1

Diabetes mellitus can increase the risk of complicated UTIs 2
Immunosuppression from any cause can complicate UTIs 2
Voiding dysfunction of neurological or other origin can also contribute to complicated UTIs 1

Repeated pyelonephritis episodes (upper tract involvement) may indicate a complicated UTI 1
Bacterial cystitis that recurs rapidly (within 2 weeks of initial treatment) after symptom resolution can suggest a complicated UTI 2
Bacterial persistence without symptom resolution despite appropriate therapy may indicate a complicated UTI 2
Symptoms of pneumaturia or fecaluria suggesting fistulous connection can complicate a UTI 2
Gross hematuria after infection resolution may be a sign of a complicated UTI 2

Prior urinary tract surgery or trauma can increase the risk of complicated UTIs 2
Prior urinary tract calculi can also contribute to complicated UTIs 2
Prior abdominopelvic malignancy may increase the risk of complicated UTIs 2
Prior diverticulitis can also be a risk factor for complicated UTIs 2
Urea-splitting bacteria on culture (suggesting possible stone formation) may indicate a complicated UTI 2

While E. coli remains the most common pathogen in all UTIs (approximately 75%), complicated UTIs more frequently involve other organisms such as Enterococcus faecalis, Proteus mirabilis, Klebsiella, or Staphylococcus saprophyticus 1
Infections with resistant organisms or unusual pathogens should raise suspicion for a complicated UTI 1

Relapses (chronic infections with the same organism) rather than reinfections with different organisms may indicate a complicated UTI 2
Recurrence within 2 weeks of completing appropriate therapy can suggest a complicated UTI 2
Three or more symptomatic UTI episodes within 12 months that do not respond to conventional therapy may indicate a complicated UTI 3

Failure to respond to appropriate empiric antimicrobial therapy can be a sign of a complicated UTI 4

Patients with complicated UTIs often require imaging studies to identify structural abnormalities 2, 3

In a prospective multicenter trial of 119 patients undergoing STARR procedure for rectocele repair, UTI was specifically listed among the adverse events occurring in 15% of patients 5, 6, 7
The underlying pelvic floor dysfunction—impaired pelvic floor relaxation and excessive straining—that causes rectoceles also contributes to urinary retention and incomplete bladder emptying 5, 6

Initial management should focus on pelvic floor biofeedback therapy, which addresses the underlying dysfunction for both conditions 5, 6, 7
Surgical repair of rectocele alone may not resolve UTI issues if concurrent cystocele or voiding dysfunction is not addressed 5

The correlation between rectocele size and symptoms is weak—a large rectocele does not necessarily cause more UTIs 5, 6, 7
Surgical correction of the rectocele does not address the underlying pelvic floor dysfunction, which is the root cause of both conditions 5, 6