UAA and AAUS issue new guidelines on UTI diagnosis and treatment
Complicated and uncomplicated urinary tract infections (UTIs) in adults and children should be managed by identifying and treating predisposing or underlying risk factors, with antimicrobial treatment, if needed, based on urine culture results and regional antibiotic resistance patterns, according to new guidelines of the Urological Association of Asia (UAA) and Asian Association of UTI and STD (AAUS).
“UTI, whether febrile or non-febrile, is caused by entrance of bacteria into the bladder, followed by bacterial retention and multiplication in the bladder with or without vesicoureteral reflux [VUR]. Bladder-bowel dysfunction [BBD] is the leading risk factor among others such as vaginal reflux and neurogenic bladder,” explained Dr Stephen Yang of Taipei Tzu Chi Hospital, New Taipei, Taiwan. “Recognizing and treating BBD aggressively is therefore very important in the treatment of UTIs in children, and likely in adults as well.”
Uncomplicated UTIs are usually sporadic and community-acquired episodes in otherwise healthy individuals, while structural and functional abnormalities, such as neurogenic bladder and BBD, are associated with complicated UTIs. The urine dipstick test alone could be used to diagnose UTI with a specificity of up to 98 percent if positive for both leukocyte esterase and nitrites. Radiological investigations are often necessary for detailed diagnosis. For example, ultrasound is used to rule out urinary obstruction or renal stone disease, while unenhanced helical CT, excretory urography or dimercaptosuccinic acid (DMSA) scanning is used in febrile cases after 72 hours of treatment, and abdominal CT is used in the differential diagnosis of emphysematous pyelonephritis, pyonephrosis and renal abcess.
For uncomplicated and complicated UTIs, it is a grade A recommendation that urine culture and sensitivity tests be done before initiating appropriate oral or parenteral antibiotic therapy, especially for patients at high risk of resistance.
“There is no superiority of one agent or class of antimicrobials. Regional differences in antibiotic resistance patterns should be taken into consideration,” noted Dr Bill Tak-Hin Wong from Hong Kong. “Optimal duration of therapy has not been established and ranges from 5 to a maximum of 14 days depending on severity, but 7 days is the most commonly used duration.”
“Hospital admission should be considered if complicating factors cannot be ruled out and/or the patient has clinical signs and symptoms of sepsis,” noted Dr Katsumi Shigemura of Kobe University, Japan.
“Asymptomatic bacteriuria should not be treated even in patients with neurogenic bladder who require intermittent catheterization, because treatment has not been shown to be beneficial and increases the risk of antimicriobial resistance,” highlighted Wong.
Frequent UTIs cause renal scarring, which could lead to hypertension and end-stage renal disease. Regular bowel emptying to relieve constipation and prevent faecal soiling reduces the risk of UTI.
“Patients with neurogenic bladder have increased risk of UTIs. Key preventive measures include adequate bladder drainage and catheter hygiene, neuro-urological management with oral anti-cholinergics or botulinium toxin A injection to treat neurogenic detrusor overactivity, or surgery as a last resort to restore low bladder pressure during bladder storage and voiding,” recommended Wong. “Antibiotic prophylaxis is generally not recommended because its benefit is unproven and it is associated with development of antimicrobial resistance.”
“Bladder augmentation, alone or when combined with simultaneous procedures such as surgery on bladder outlet, and/or construction of a continent abdominal stoma can produce sustainable improvements in bladder capacity and continence, reduce UTI rate and preserve renal function in the long term,” added Wong.
In children, antibiotic prophylaxis is indicated in the prevention of recurrent febrile UTI for those with moderate to high grade (III-V) VUR. “However, no benefits have been found with continuous antibiotic prophylaxis in the prevention of renal scarring,” Yang noted. [Pediatrics 2017;139:e20163145]
“Surgical intervention is recommended for such children as it has been shown to reduce the incidence of recurrent pyelonephritis,” said Yang.