1)When should we and should not treat bacteriuria in the elderly?

Knowing when to test and treat for UTI is important in geriatric populations because

• Urinalysis results have low specificity for UTI
• the presence of positive leukocyte esterase or nitrite on dipstick does not always rule in a UTI.
• Also, the presence of bacteria on culture does not equate to a UTI.

Urine testing is recommended in patients who present with classic signs and symptoms of UTI (acute dysuria, new or worsening urgency or frequency, new incontinence, gross hematuria, and suprapubic or costovertebral angle tenderness) or physiologic signs of serious acute illness (eg, fever, other major vital sign abnormalities, changes in level of consciousness)

A chart on UptoDate explains the minimum criteria for initiating antibiotics in long term care residents with UTI.

When to treat:

 

Because our patient is symptomatic and complaining of new onset burning on urination with (+) WBC’s, we definently would treat.

When we do not treat:

Patients diagnosed with Asymptomatic Bacteriuria have urine cx which show an isolation of bacteria in an appropriately collected urine specimen but do not have symptoms of urinary tract infection).

• We do not treat older patients withasymptomatic bacteriuria either in the community or in health care facilities. Numerous studies suggest that there is no clinical benefit to treatment of asymptomatic bacteriuria and that such treatment can lead to significant side effects, drug-drug interactions, expense, and potential for selection of resistant organisms.
• In this case, a reasonable management strategy in patients who do not appear seriously ill is to defer antibiotic treatment for one week with follow-up. This is because 25 to 50 percent of older women with UTI symptoms will improve without therapy in this time frame.
• We also do not treat patients with indwelling bladder catheters— and asymptomatic bacteriuria. This is because bacteriuria is extremely common among patients with indwelling catheters, and treatment does not improve patient outcomes.

 

Exceptions for treatment of UTI in patients with Asymptomatic Bacteriuria

There are a few exceptions in whom screening, and treatment are warranted in patients with asymptomatic bacteriuria;

1) Pregnancy — Asymptomatic bacteriuria during pregnancy increases the risk of pyelonephritis and has been associated with adverse pregnancy outcomes, such as preterm birth and low birth weight infants

2) Patients undergoing urologic intervention — Screening for and treatment of asymptomatic bacteriuria are warranted for patients undergoing urologic procedures in which mucosal bleeding is anticipated. Untreated bacteriuria is associated with infectious complications following urologic interventions, with a higher risk associated with procedures that disturb mucosal integrity (such as transurethral prostate interventions,(TURP) percutaneous stone surgery). In trials of patients with asymptomatic bacteriuria undergoing transurethral resection of the prostate, antibiotic treatment reduced the risk of postoperative complicated urinary tract infection and bacteremia

3) Renal transplant recipients — Some experts screen for and treat asymptomatic bacteriuria within the first three months of transplant. This is in order to prevent symptomatic UTIs, which have been associated with an increased risk of acute allograft rejection.

 

2)What antibiotic should our patient be prescribed?

Empiric antimicrobial selection — The selection of an antibiotic for UTI in our patient depends on her risk of infection with a multidrug-resistant (MDR) gram-negative organism.

We generally consider patients to be higher risk for an MDR gram-negative organism if they have any of the following occurring in the prior three months:

• An MDR gram-negative urinary isolate (ie, nonsusceptible to at least one agent in three or more antimicrobial classes; this includes extended-spectrum beta-lactamase [ESBL]-producing isolates).
• Inpatient stay in a health care facility (eg, hospital, nursing home, long-term acute care facility).
• Use of a fluoroquinolone, trimethoprim-sulfamethoxazole or broad-spectrum beta-lactam (eg, third or later generation cephalosporin)
• Travel to parts of the world with high rates of MDR organisms (eg, India, Israel, Spain, Mexico)

For patients who have risk factors for an MDR gram-negative infection, we first obtain urine culture and susceptibility testing. For empiric treatment, the best oral option is Nitrofuratonin monohydrate/macrocrystals (Macrobid, 100 mg orally twice daily for five days).

 

3)Flouroquinolones as a class and how perspective has changed on their use?

Fluoroquinolones are highly effective antibiotics with many advantageous pharmacokinetic properties including high oral bioavailability, large volume of distribution, and broad-spectrum antimicrobial activity. In the past decade, fluoroquinolones (FQs) have significantly been used less as empiric usage for many gram-negative (GN) infections. This is because its widespread use has led to increased antimicrobial resistance. In addition, fluoroquinolones carry risk of serious adverse effects and have multiple drug-drug interactions.The US (FDA) has issued statements regarding the preferential use of alternative therapy for many common disease states because the risks of fluoroquinolone use outweigh the benefits for  uncomplicated infections such as acute rhinosinusitis, uncomplicated cystitis, and acute bronchitis.

Adverse Effects associated with Fluoroquinolone use

GI system: C. diff infection, Gastritis, hepatotoxicity

Neurologic system:  has the most common adverse effects, but most are mild like headache and dizziness. Some less common but more serious CNS effects range from delirum/AMS ( even w/ single dose), to hallucination to seizure, peripheral neuropathy( can last months to years after drug is stopped) . Also FQ have neuro-muscular blocking activitiy which can exacerbate myasthenia gravis.

Cardio- QT prolongation by inhibiting cardiac KCHN2 potassium voltage-gated channels, potentially leading to torsades de pointes (a life-threatening arrhythmia). Also Increased risk of Aortic aneurysm and dissection

Musculoskeletal- Tendon rupture(Achilles MC, recommend pt to avoid exercise)

Dysglycemia — Fluoroquinolones have been associated with both hypoglycemia and hyperglycemia in both diabetic and nondiabetic patients

Retinal detachment has been reported with fluoroquinolone use; however, a causal relationship has not been established

Phototoxicity — Some fluoroquinolones carry a small risk of phototoxicity.

Hypersensitivity reactions — Delayed-onset maculopapular rash is the most common type of hypersensitivity reaction to fluoroquinolones, occurring in approximately 2 to 3 percent of patients.

 

 

Source:

1)https://www-uptodate-com.york.ezproxy.cuny.edu/contents/approach-to-infection-in-the-older-adult?search=uti%20in%20elderly%20women&source=search_result&selectedTitle=1~150&usage_type=default&display_rank=1#H3210518268

2)https://www-uptodate-com.york.ezproxy.cuny.edu/contents/urinary-tract-infections-and-asymptomatic-bacteriuria-in-pregnancy?sectionName=ASYMPTOMATIC%20BACTERIURIA&search=uti%20in%20elderly%20women&topicRef=8061&anchor=H2&source=see_link#H2

3)https://www.contagionlive.com/publications/contagion/2019/april/future-of-fluoroquinolones-risks-benefits-of-antibiotic-workhorse

4)https://www-uptodate-com.york.ezproxy.cuny.edu/contents/fluoroquinolones?search=fluoroquinolones&source=search_result&selectedTitle=2~150&usage_type=default&display_rank=1#H24

5)https://www-uptodate-com.york.ezproxy.cuny.edu/contents/image?imageKey=ID%2F115993&topicKey=ID%2F8063&search=eldery%20uti&source=see_link