Vibhash Mishra and Jas S Kalsi
Q. What is the definition of urinary tract infection?
A. Urinary tract infection (UTI) is the inflammatory response of urothelium to micro-organism invasion (commonly bacterial), usually associated with bacteriuria and pyuria.
Q. What is the definition of bacteriuria?
A. Bacteriuria is the presence of bacteria in urine.
Q. What is the definition of pyuria?
A. Pyuria is the presence of white blood cells (WBCs) in urine.
Q. What is the definition of sterile pyuria and what is the differential diagnosis?
A. Sterile pyuria is pyuria, without bacteriuria. Possible causes include tuberculosis, carcinoma in situ of bladder, schistosomiasis, urinary tract stones, partly treated UTI and other inflammatory bladder conditions (interstitial cystitis or leucoplakia).
Q. What is the definition of cystitis?
A. Cystitis is a clinical syndrome of dysuria, frequency and urgency with or without suprapubic pain.
Q. What is the definition of acute and chronic pyelonephritis?
A. Acute pyelonephritis is a syndrome comprising flank pain, nausea and vomiting, fever (>38°C) or costovertebral angle tenderness. Chronic pyelonephritis is a radiological diagnosis describing a scarred, shrunken kidney, which may or may not have resulted from recurrent infections.
Q. What is the definition of an isolated UTI?
A. An isolated UTI is one which occurs at least 6 months after the previous UTI.
Q. What is the definition of recurrent UTI?
A. Recurrent UTI is an episode of UTI after documented, successful resolution of an earlier episode and occurring at a frequency of at least twice in the last 6 months, or three times in the last 12 months. Recurrent UTI can be sub-classified as ‘persistent’ or ‘re-infection’:
What is the definition of persistence?
Persistence refers to recurrent UTI caused by the same organisms. It indicates a possible focus of infection in the urinary tract such as stones (commonly struvite), chronic prostatitis, bladder diverticulum, urethral diverticulum and colo-vesical fistula.
What is the definition of re-infection?
Re-infection refers to recurrent episodes of UTI caused by different organisms. It usually indicates an increased susceptibility to UTI (including genetic), and is associated with poor hygiene, sexual intercourse, post-menopause. More than 95% of all recurrent UTIs in females are due to re-infection.
Q. What is the definition of unresolved infection?
A. An unresolved infection is one that has not responded to treatment. Possible causes include natural or acquired bacterial resistance to antimicrobial therapy, development of resistance in a previously susceptible organism, simultaneous infection with multiple organisms, rapid reinfection, an overwhelming size of bacterial inoculums or antimicrobial level below the minimum inhibitory concentration.
Q. What is the definition of a complicated UTI?
A. A complicated UTI indicates infection in the presence of a structurally or functionally abnormal urinary tract, or UTI in the presence of underlying disease which is known to increase the risk of acquiring infection, or failing therapy.
Factors suggesting complicated UTI include male gender, being elderly and pregnancy, The presence of an indwelling catheter, stent (urethral, ureteral, renal) or the use of intermittent bladder catheterization, indwelling catheter/stent, recent urinary tract instrumentation, immunosuppression, diabetes, symptoms for >7 days at presentation, hospital-acquired infection, recent antimicrobial use, functional (vesicoureteric reflux) or anatomical abnormality of the urinary tract (ileal loop or pouch, post-void residual urine of >100 mL, an obstructive uropathy of any aetiology (upper and lower urinary tracts), e.g. bladder outlet obstruction (including neurogenic urinary bladder), stones and tumour, or chemical or radiation injuries of the uroepithelium [1].
Q. What is the definition of an uncomplicated UTI?
A. An uncomplicated UTI indicates infection in the presence of a structurally or functionally normal urinary tract, or UTI in the absence of any underlying disease that increases the risk of acquiring infection, or failing therapy.