Urinary Tract Infection (UTI)

00:01 All right.

00:02 Are you ready to talk about the dreaded urinary tract infection? We’re going to cover some epidemiology and some microbiology, but mostly discuss some pearls that, I think, will really help you in practice regarding diagnosis and management.

00:15 Let’s go.

00:17 So, in terms of epidemiology, definitely more females than males get urinary tract infections.

00:24 In fact, over a lifetime, about half of all women experience a urinary tract infection.

00:30 And of course, E. coli cause most cases of UTI, but certainly have to think about other less common organisms, Staph saprophyticus, Klebsiella, Enterobacter.

00:42 And the symptoms, I think you know, they're fairly classic, dysuria being the most common, frequency of urination.

00:49 And just those two symptoms alone, without any vaginal symptoms, such as vaginal discharge or burning, has a 90% positive predictive value in identifying urinary tract infections.

01:03 And this is something that I've actually learned that I didn’t necessarily know because I usually want patients to come in and get checked out.

01:10 But if a – particularly a female patient calls in and complains of dysuria, along with increased frequency, no vaginal symptoms, they actually did a study and found that only 5% of cases of urinalyses were negative in a study of telephone management.

01:26 So, these cases actually can be managed over the phone and might be a good indication to give antibiotics just right there on the spot to help treat the UTI.

01:35 Because physical examination is fairly limited for identifying urinary tract infection.

01:41 Classic is suprapubic tenderness to palpation, but only one in five women at most actually have significant suprapubic tenderness to palpation.

01:49 Always check for costovertebral angle tenderness because of the risk for ascending infection and pyelonephritis.

01:55 But I do think that one pearl I've learned in managing patients with suspected UTI is that there's a difference between costovertebral angle tenderness that’s mild where it’s like, yes, that kind of hurts.

02:08 If it’s pyelonephritis or a perinephric abscess or some more severe infection, touching that back, just even a gentle touch or a light touch like that, will really make the patient jump. It really hurts.

02:23 So, if it’s just a mild kind of soreness, that doesn’t necessarily qualify as costovertebral angle tenderness, because once I chart CVAT, I have to treat like I'm treating pyelonephritis, and that's different from most UTIs.

02:38 Patients, of course, get a urinalysis.

02:41 Urine culture isn't necessary for every case, and this may come up on your examination, but certainly for more complicated cases.

02:48 Recurrent UTIs, women who are pregnant, immunocompromised or immunocompromising conditions and diabetes, all those patients get routine cultures, but a healthy younger woman doesn't need routine culture.

03:04 And they found that, even with the classic symptoms present, that even as low as 100 colony-forming units per milliliter, can be suggestive and diagnostic for UTI among otherwise healthy patients.

03:18 Kind of remarkable.

03:19 Much lower threshold than there was in the past when it had to be 105 CFU per milliliter in order to diagnose UTI.

03:28 In terms of management, we reach to antibiotics.

03:30 And I can tell you there is not one that's perfect.

03:32 First line is still considered trimethoprim sulfamethoxazole or co-trimoxazole, but usually three days is acceptable.

03:43 Try to think about what your rates of resistance are when you're getting cultures back.

03:47 If your rates of resistance to TMP-SMX exceed 20%, in my practice, they probably see 30 to 40%, it’s probably better to reach for another drug.

04:00 The one I usually reach for, nitrofurantoin, it's an older drug, but associated with lower rate of resistance.

04:06 Unfortunately, multiple times per day dosing and you have to take it for five days, but generally well tolerated and more effective.

04:13 And then fosfomycin is also an option, and that's just one dose for a very convenient type of dosing schedule.

04:20 Second line agents include fluoroquinolones which are effective, but we are trying to practice stewardship and avoid overuse of fluoroquinolones and avoid the spread of fluoroquinolone resistance.

04:34 So, let’s talk about UTI in kids because this is an issue that comes up in practice, but also very much will come up on your examination.

04:41 So, first of all, abnormal urinalysis, so with white cells or nitrite, leukocyte esterase, plus at least 50,000 colony-forming units per milliliter.

04:52 Now, for kids, it's a special case.

04:55 You want to look for congenital abnormalities of the renal and bladder system.

05:00 So, therefore, doing an ultrasound on those organs is important even after a first UTI between 2 and 24 months of age.

05:08 However, what was also recommended in the past was avoiding cystourethrogram.

05:14 That's no longer recommended.

05:16 So, I think that might be the exam question you get is, what is indicated.

05:20 So, culture would be indicated.

05:21 Urinalysis would be indicated. Ultrasound would be indicated.

05:24 VCUG would not be indicated for first UTI in cases of between 2 and 24 months.

05:30 Second UTI, yes, it would be.

05:32 Checking for reflux.

05:34 So, in terms of management of UTI among young children, oral antibiotics are acceptable.

05:41 They don’t have to be put in the hospital.

05:43 Previously, everybody required parenteral antibiotics.

05:46 So, IV only if they're really sick, but it is a longer duration of treatment.

05:50 It’s between 7 to 14 days, depends on the practitioner.

05:53 But it’s not – no three or five-day options are available for children.

05:59 So, that's a brief overview of urinary tract infection.

06:02 A common diagnosis.

06:03 We may kind of take for granted, but hopefully you’ve gained a few pearls there in terms of clinical wisdom that it may be able to be manage on the phone in those classic cases.

06:14 You got some insight into antibiotics.

06:16 And particularly the workup in kids.

06:18 Those are all good things to know for your exam and for your clinical practice as well.

06:24 Thanks very much.