Low-count bacteriuria in refractory idiopathic detrusor overactivity versus controls

Abstract

<em>Background.</em> Previous studies suggest an association between idiopathic detrusor overactivity (IDO) and high-count bacteriuria (>105 CFU/mL). Recently, the importance of low-count bacteriuria (103–105 CFU/mL) in dysuric women with has been recognised. However, the optimal microbiological threshold for women with overactive bladder (OAB) symptoms remains unclear<strong>. </strong><em>Design and Methods</em> A 2-year prospective cohort study, to examine the incidence of low-count and high-count bacteriuria in women with refractory IDO (RIDO) versus a control group without OAB symptoms. Women with dysuria, voiding dysfunction or recent urethral instrumentation were excluded. Mid-stream urine (MSU) specimens were collected during acute symptomatic exacerbation in the IDO group and cultured at the 103 CFU/mL threshold. Statistical analysis was performed using Statsdirect statistical package 2.7.2. <em>Results</em><strong>.</strong> Between November 2007 and November 2009, 218 study MSU specimens were collected. Both the overall incidence of any significant bacteriuria ≥103 CFU/mL (P<0.0001) and the incidence of low-count bacteriuria (P=0.0091) were significantly higher in the RIDO women than the controls. There were no baseline differences in age, menopausal status or prior continence surgery between the groups. In the RIDO group, specimens positive for low-count bacteriuria only were less likely to be associated with significant pyuria P<0.0001) and were cultured from younger women (P=0.0009), than specimens positive for high-count bacteriuria. Conclusions The prevalence of bacteriuria in women with RIDO during symptomatic exacerbation is 40%, which is significantly higher than the incidence in similarly-aged women without OAB. One-third of positive cultures show low-count bacteriuria only. The management of women with RIDO should include a search for bacteriuria, including low-count bacteriuria

Host–pathogen checkpoints and population bottlenecks in persistent and intracellular uropathogenicEscherichia colibladder infection

“…A study of midstream urine specimens from 50 refractory OAB women and 50 controls obtained positive urine cultures (≥ 10 3 CFU mL −1 ) from 39% of those with urge incontinence compared with 6% of controls ( P < 0.0001), with the majority of these UTI caused by E. coli , and associated pyuria (Walsh et al ., ). A later study of catheterized urine specimens from patients with newly diagnosed OAB revealed bacteriuria in 13%, the majority culturing E. coli with pyuria, vs. 6% of controls ( P = 0.07; Walsh et al ., ). Thus, it appears that in this subset of refractory OAB, up to one‐third of patients may exhibit bacterial cystitis, albeit without expression of the dysuria or foul‐smelling urine symptoms that have been considered the classic hallmarks of UTI.…”

“…On the other hand, patients presenting with the main complaints of frequency/urgency/nocturia/urge incontinence without dysuria and bacteriuria (>10 5 CFU mL −1 ) are considered to have the OAB syndrome (Walsh & Moore, ). However, recent evidence has demonstrated pyuria (Horsley et al ., ) and low‐count (≥ 10 3 CFU mL −1 ) bacteriuria on catheter specimens in patients diagnosed with OAB (Walsh et al ., ; Walsh & Moore, ). Furthermore, recent evidence indicates that a portion of women with refractory OAB experience recurrent episodes of bacterial cystitis that manifest as acute exacerbations of the frequency/urgency/nocturia/urge incontinence symptoms, without the classical dysuria or foul‐smelling urine usually associated with bacteriuria.…”

Asymptomatic bacteriuria: prevalence rates of causal microorganisms, etiology of infection in different patient populations, and recent advances in molecular detection

“…If such patients are found to have two cultures of the same species 24 h apart, with bacteriuria ≥ 10 5 CFU mL −1 of uropathogens (Grabe et al ., ), in the absence of dysuria, controversy now exists as to whether such women should be considered as having ABU, or in fact, a sUTI that warrants treatment. Recent evidence indicates that 26% of women with severe OAB may have ≥ 10 5 CFU mL −1 without the classical features of dysuria or malodorous urine, compared with 4% of age‐matched continent controls (Walsh et al ., ). The role of urine leakage onto the perineum with possible facilitation of bacterial colonization of the urethral orifice remains controversial also, because patients with OAB leak urine intermittently, not continuously.…”

Botulinum toxin in “refractory” detrusor overactivity. Re: Makovey I, et al. Botulinum toxin outcomes for idiopathic overactive bladder stratified by indication: Lack of anticholinergic efficacy versus intolerability. Neurourol Urodyn 2011;30:1538–1540

“…We found that, in non‐dysuric women with “refractory” DO, the prevalence of bacteriuria≥10 3 CFU/ml, at a time of clinically worsened urgency symptoms, was 39% 3. Notably, only “low‐count” bacteriuria (10 3 –10 5 CFU/ml) was cultured in one‐third of positive cases in our study 3. This is pertinent as the importance of low bacterial counts in patients with lower urinary tract symptoms is increasingly recognized 4.…”

“…The concept of “refractory” DO has not been well studied and no general consensus exists on the most appropriate definition 2. We previously reported a 2‐year prospective study on the prevalence of bacteriuria in women with “refractory” DO (defined as “ failure to respond to ≥ 2 anti‐cholinergic agents coupled with out‐patient bladder training for ≥ 1 year, with persistent disabling symptoms on frequency‐volume chart” ) during episodes of acute exacerbation of OAB symptoms 3. We found that, in non‐dysuric women with “refractory” DO, the prevalence of bacteriuria≥10 3 CFU/ml, at a time of clinically worsened urgency symptoms, was 39% 3.…”