Episode 69 - Asymptomatic Bacteriuria - a podcast by Rio Bravo Family Medicine Residency Program

Episode 69: Asymptomatic Bacteriuria. 

When do you screen for and treat asymptomatic bacteriuria? Find out what the IDSA recommends during this episode. PARTNER studies demonstrated that HIV transmission is minimal with condom-less sex if viral load is undetectable.

Introduction: Urine.  

Urine is a straw-colored, pale yellow, or colorless liquid, which is a by-product of metabolism. It is normally sterile when excreted under normal conditions, but it can also have bacteria even in the absence of infection. When you have bacteriuria with no symptoms, it is called asymptomatic bacteriuria or ASB. Today you will hear Dr Covenas, Dr Civelli and Dr Lundquist discussing when to screen and treat asymptomatic bacteriuria.

This is Rio Bravo qWeek, your weekly dose of knowledge brought to you by the Rio Bravo Family Medicine Residency Program from Bakersfield, California. Our program is affiliated with UCLA, and it’s sponsored by Clinica Sierra Vista, Let Us Be Your Healthcare Home. [Music continues and fades…]

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Asymptomatic bacteriuria (update by the IDSA)
Written by Hector Arreaza, MD. 
Participation by Cecilia Covenas, MD; Valeri Civelli, MD; and Ariana Lundquist, MD.

Case: 19-year-old female who came to clinic to review lab results with you. She is coming from another clinic and brings her results on paper. Routine labs were done 1 week ago. Her complete blood count is normal, TSH (thyroid stimulating hormone) is normal, hemoglobin A1C of 5.3, and a urine culture showing >100,000 CFU of E. coli. Patient denies dysuria, polyuria, or any urinary symptoms. She has a negative pregnancy test in clinic today. What are you going to do with this significant bacteriuria?

This is an Asymptomatic Bacteriuria (ASB). The first question you may ask is “why did she get a urine culture in the first place?” The Infectious Disease Society of America (IDSA) published in its journal “Clinical Infectious Disease” an update in the management of ASB. It is a 28-page long document with answers to 14 questions regarding ASB screening and management in different patient populations.

Recommended ASB screening and treatment: IDSA concluded that the only two groups of patients who benefit from screening and treatment of asymptomatic bacteriuria are: Pregnant women and patients who undergo traumatic urologic interventions that result in mucosal bleeding.

Pregnant women: Recommend one urine culture at one of the initial visits early in pregnancy. There is insufficient evidence to recommend for or against repeat screening during the pregnancy for a woman with an initial negative screening culture or following treatment of an initial episode of ASB. Treatment: IDSA suggests 4–7 days of antimicrobial treatment rather than a shorter duration, the optimal duration of treatment will vary depending on the antimicrobial given; the shortest effective course should be used.

 

Patients who will undergo endoscopic urologic procedures associated with mucosal trauma: Screening for ASB and treating prior to surgery is RECOMMENDED. The goal is to avoid serious post-operative complication of sepsis. IDSA suggests a urine culture prior to the procedure and targeted antimicrobial therapy prescribed rather than empiric therapy. If bacteriuria is detected, a short course (1 or 2 doses) rather than more prolonged antimicrobial therapy is recommended, and antibiotic should be initiated 30–60 minutes before the procedure.

Against ASB screening and treatment: IDSA suggests no screening for or treating ASB in these patients:

Pediatric patients

Healthy nonpregnant women

Community-dwelling persons who are functionally impaired

Older persons residing in long-term care facilities

Patients with diabetes

Patients who had a renal transplant over 1 month ago (insufficient evidence for less than 1 month ago)

Patients with nonrenal solid organ transplant

Individuals with impaired voiding following spinal cord injury (consider atypical symptoms of UTI when deciding treatment vs nontreatment of bacteriuria in these patients)

Short-term indwelling urethral catheter (<30 days)

Patients with long-term indwelling catheters (>30 days)

Patients undergoing elective nonurologic surgery

Patients planning to undergo surgery for an artificial urine sphincter or penile prosthesis implantation (these patients should receive standard preop antibiotics before surgery)

Patients living with implanted urologic devices

Insufficient evidence to recommend for or against ASB screening and treatment: Evidence is insufficient to recommend ASB screening and treatment in patients with high-risk neutropenia (absolute neutrophil count <100 cells/mm3, >7 days duration after chemotherapy). These patients should be treated with prophylactic antibiotics and start antibiotics promptly in there is fever. For low-risk neutropenic patients (neutrophils >100, <7 days, clinically stable) ASB risk is not greater than in patients with normal neutrophil count. In patients with indwelling catheters, IDSA makes no recommendation for or against screening and treating ASB at the time of catheter removal.

Special populations: In older patients with cognitive impairment with bacteriuria and confusion WITHOUT urinary symptoms or other signs of infection, such as fever or hemodynamic instability: Look for causes of altered mental status other than UTI, have close monitoring of symptoms, antibiotics are NOT recommended as a first line treatment unless you have signs or symptoms of infection.

If a patient with these characteristics (older, cognitively impaired, nonlocalizing symptoms) experienced a fall, the recommendation is the same: assess for other causes and observation rather than antimicrobial treatment of bacteriuria. 

The reason behind this recommendation is avoiding adverse outcomes of antibiotic therapy (C. diff, increased antibiotic resistance, or adverse drug effects). 

Sepsis: For patients with BACTERIURIA, fever, and other systemic signs potentially consistent with sepsis and without a localizing source, broad-spectrum antimicrobial therapy directed against urinary and nonurinary sources should be initiated. 

As for our non-pregnant 19-yo female patient with significant bacteriuria and no urinary symptoms, the answer is do not treat.

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HIV Series Part III: PARTNER 1 and PARTNER 2

Hello everyone! Welcome back to the introduction to HIV series with the Rio Bravo qWeek Podcast. Today we will focus on the PARTNER-1 and PARTNER-2 studies. Let’s review these studies together. 

The PARTNER-1 and PARTNER-2 studies were important in providing evidence-based support for the claim undetectable equals untransmissible, or U=U. SO in this podcast, we can break down what these studies are. 

Previous studies

In 2011, the HIV Prevention Trials Network (HPTN) 052 study team conducted a clinical trial demonstrating a 96% reduction in HIV transmission amongst heterosexual couples when one partner is HIV positive and the other is HIV negative. However, in this study and other, there was still consistent condom use and PrEP use and no data concerning anal sex. 

PARTNER 1 study

The PARTNER 1 (Partners of People on ART – A New Evaluation of the Risks) study was the first observational study to assess the risk of HIV transmission between couples, including both heterosexual and homosexual couples, without condoms, and including anal sex. It was conducted from September 2010 to May 2014, enrolled 1166 couples, and reported 22,000 condomless sex acts amongst men who have sex with men (MSM) and 36,000 condomless sex acts amongst heterosexual couples. The HIV positive partner had to maintain their viral load below 200 copies/mL and the HIV negative patient was not to use condoms or be on pre-exposure prophylaxis (PrEP) in order to be eligible for the study. The results showed that there were no documented cases of within-couple HIV transmission, with a 95% confidence limit.

Some limitations to the study include that there were 11 patients who were HIV negative that contracted HIV during the study time. However, none of the HIV genotypes were phylogenetically linked to the HIV positive partner. Furthermore 8 of these patients endorsed that they were engaging in sex with people other than their partner. Another limitation was that this was an observational study, so all the parameters of the study are self-reported. And the study was conducted for 4 years, so a longer study would need to be conducted to give a stronger estimate of risk. 

PARTNER 2 study

In the PARTNER 2 study, the observational study was focused on only homosexual men (MSM), enrolled some patients from PARTNER 1 study, and therefore included data from September 2010 to April 2018. Once again, the study collected data about their sexual behavior, required the HIV positive partner to maintain a viral load below 200 copies/mL, and required condomless sex and no use of PrEP or post-exposure prophylaxis (PEP) to be eligible for the study. This study enrolled 972 gay couples, contributing to 1596 couple years (years they have been together) and documented 77000 condomless sex acts. The findings once again demonstrated no HIV transmission within couples.

A limitation to this study is that 15 patients did contract HIV, however, none of the new infections could be phylogenetically linked to their partner from the study. Furthermore, it is important to note that 37% of the couples were in open relationships, 24% of the HIV negative partners contracted at least one STI and 27% of the HIV positive patients contracted at least one STI. 

Significance

The significance of this study demonstrates the effectiveness of HAART therapy in not only treating a patient with HIV, but also demonstrates that “undetectable” levels of HIV viral loads does mean it is untransmissible. The common campaign symbol “U=U” (undetectable = untransmissible) is often used to promote this concept. And these studies finally give us evidence-based data to demonstrate U=U. Hopefully with more education, the prejudice surrounding people living with HIV can be removed. 

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Conclusion: Now we conclude our episode number 69 “Asymptomatic Bacteriuria.” When do you screen for and treat asymptomatic bacteriuria? The answer is, in pregnant women and in patients who will undergo traumatic urology procedures. Robert also explained in his HIV series that the PARTNER 1 and PARTNER 2 studies showed no transmission of HIV to a seronegative partner when the seropositive partner has undetectable viral load, even without use of condoms. Even without trying, every night you go to bed being a little wiser.

Thanks for listening to Rio Bravo qWeek. If you have any feedback about this podcast, contact us by email RBresidency@clinicasierravista.org, or visit our website riobravofmrp.org/qweek. This podcast was created with educational purposes only. Visit your primary care physician for additional medical advice. This week we thank Hector Arreaza, Cecilia Covenas, Valerie Civelli, Arianna Lundquist, and Robert Dunn. Audio edition: Suraj Amrutia. See you next week! 

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References:

Nicolle LE, Gupta K, Bradley SF, Colgan R, DeMuri GP, Drekonja D, Eckert LO, Geerlings SE, Köves B, Hooton TM, Juthani-Mehta M, Knight SL, Saint S, Schaeffer AJ, Trautner B, Wullt B, Siemieniuk R. Clinical Practice Guideline for the Management of Asymptomatic Bacteriuria: 2019 Update by the Infectious Diseases Society of America. Clin Infect Dis. 2019 May 2;68(10):e83-e110. doi: 10.1093/cid/ciy1121. PMID: 30895288. [https://pubmed.ncbi.nlm.nih.gov/30895288/]  

 

Cohen MS, Chen YQ, McCauley M, Gamble T, Hosseinipour MC, Kumarasamy N, Hakim JG, Kumwenda J, Grinsztejn B, Pilotto JH, Godbole SV, Mehendale S, Chariyalertsak S, Santos BR, Mayer KH, Hoffman IF, Eshleman SH, Piwowar-Manning E, Wang L, Makhema J, Mills LA, de Bruyn G, Sanne I, Eron J, Gallant J, Havlir D, Swindells S, Ribaudo H, Elharrar V, Burns D, Taha TE, Nielsen-Saines K, Celentano D, Essex M, Fleming TR; HPTN 052 Study Team. Prevention of HIV-1 infection with early antiretroviral therapy. N Engl J Med. 2011 Aug 11;365(6):493-505. doi: 10.1056/NEJMoa1105243. Epub 2011 Jul 18. PMID: 21767103; PMCID: PMC3200068. [https://www.nejm.org/doi/full/10.1056/nejmoa1105243] 

 

Rodger AJ, Cambiano V, Bruun T, et al. Sexual Activity Without Condoms and Risk of HIV Transmission in Serodifferent Couples When the HIV-Positive Partner Is Using Suppressive Antiretroviral Therapy. JAMA. 2016;316(2):171–181. doi:10.1001/jama.2016.5148. [https://jamanetwork.com/journals/jama/fullarticle/2533066] 

 

Rodger AJ, Cambiano V, Bruun T, Vernazza P, Collins S, Degen O, et al. Risk of HIV transmission through condomless sex in serodifferent gay couples with the HIV-positive partner taking suppressive antiretroviral therapy (PARTNER): final results of a multicentre, prospective, observational study. The Lancet. 2019; 393(10189): 2428-2438. Doi: 10.1016/S0140-6736(19)30418-0. [https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(19)30418-0/fulltext]

 

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