Tag Archives: clinical details

“Reporting susceptibilities on UTIs, not urinary isolates…”

Antimicrobial Resistance, Antimicrobial Stewardship, , , ,

Urines arrive at diagnostic microbiology laboratories in considerable numbers. My own lab in New Zealand processes a couple of thousand urines a week. A significant proportion of these will have positive cultures. Therefore, the potential for the laboratory to promote good antimicrobial stewardship with respect to urinary tract infection is considerable.

My mantra on this is as follows: “The microbiology lab should never release antibiotic susceptibilities on a positive culture from a urine sample unless there is reasonable evidence accompanying the request that the patient has a UTI.”

The fact that the urine sample has turned up at the microbiology lab is insufficient evidence per se that the patient has a UTI. Urines get sent to microbiology laboratories for all sorts of spurious reasons, see below for a few examples:

  • Urines often get sent “automatically” from acute receiving wards as part of a blanket laboratory screen, where the patient may have a diverse spectrum of symptoms such as chest pain, shortness of breath, collapse, etc.
  • Urines can get sent from Long Term Care Facilities when someone decides to dipstick all their patients and send the urine samples with positive dipsticks to the lab for culture. Yes, it happens, and a lot more often than you might think!
  • Urine from indwelling catheters can get sent when the patient has a blocked catheter, or the catheter bag is cloudy.
  • Urines from patients attending outpatient clinics should also raise a flag. With the exception of urology clinics, patients who attend a pre-planned elective clinic appointment generally do not have an acute UTI. The same principle can apply for patients who are in hospital wards for other reasons.
  • Urines where the clinicians are looking for other tests, i.e. albumin/creatinine ratio, and due to laboratory processes the urine ends up getting cultured as well…

So, my argument is that if a urine sample turns up at the laboratory without any clinical details or with inappropriate clinical details, the lab is under no obligation whatsoever to release antibiotic susceptibilities on any organisms grown. 

The best approach of course is not to process the sample at all unless relevant clinical details are received. I would regard all of the following clinical details as being unacceptable to justify proceeding to urine culture:

  • No clinical details
  • Cloudy urine
  • Concentrated urine
  • Dark urine
  • Smelly urine
  • Urine dipstick urinalysis results only
  • Routine/monitoring/screening urine
  • Fatigue
  • Increased CRP
  • Lots of other non-specific symptoms!

The easy option for the lab of course is just to accept the sample, report the organisms, and the accompanying susceptibilities. However, this is almost certainly not the best way…

Michael

“A simple approach to uncomplicated UTI”

Confessions of a Microbiologist, The Art of Microbiology, , ,

We have a “no clinical details-no test” policy at my lab, so in general, we get accompanying clinical details with the vast majority of samples received for microbiology testing. After all, at the end of the day, clinicians just want their requests processed…

This is great, but it always irritates me slightly when we get a urine sample into the laboratory from a young adult female with symptoms of a straightforward cystitis with no supporting clinical information to suggest that a “complicated UTI” is being queried.

My first reaction when seeing this is “Why are you sending this urine sample to the lab? Do you think this is going to help your patient?”

In New Zealand, and I suspect most of the rest of the world, uncomplicated UTIs are treated empirically according to local antibiograms, usually with a short course of nitrofurantoin or trimethoprim. In most cases, this settles things down, and no further medical input is required.

We receive approximately 400 urine samples for microbiology processing into our lab each day. My rough estimate is that 5-10% of these urines have clinical details that suggest an uncomplicated UTI. It doesn’t sound much, but it certainly adds up over the course of a year, and the total cost of processing all these would likely cover a scientist’s salary.

...And if we received urine cultures into the lab on every uncomplicated UTI diagnosis, then we would be completely overwhelmed!

During the early stages of the COVID pandemic, when we were getting hammered by SARS-CoV-2 PCR requests, we urged clinicians to send us critical samples only. This certainly reduced the number of requests where the clinical details suggested uncomplicated UTI. But old habits die hard, and now we are more or less back to baseline.

I have often wondered whether we should only accept urines where the clinical details are suggestive of a complicated UTI, but we have not gone there yet. Some might wonder if such an approach is too “hardline”, but it remains an option and I think a very reasonable one at that.

People sometimes think diagnostic stewardship is all about optimising the use of very expensive laboratory tests, e.g multiplex PCR assays, but in actual fact, looking after less costly but higher volume tests such as urine culture is every bit as important…

Michael

Building the CDC in your community

Confessions of a Microbiologist,

I am not referring here to the Centre for Disease Control, which is a great resource which I use often to look up things I should know anyway, but don’t.

I am referring to the acronym “Clinical Details Culture”, an equally important CDC in my mind.

At the laboratory I work in, we have just implemented a mandatory clinical details policy for all microbiology samples. The only exceptions are those “difficult to obtain” samples taken from sterile site areas. For everything else, if there are no clinical details supporting the testing, then no testing is performed by the laboratory.

Now when I sign out a list of microbiology results I have clinical details on each and every request form. This is wonderful! In a good percentage of cases it changes both the testing and reporting of results. In other words the quality of results being produced has improved. And no longer will I get staff complaining to me that there are no clinical details on forms!

This has not been an easy policy to implement. Even after several months of preparation, there have been a few (almost inevitable) teething  problems which have had to be worked through. One key area is ensuring that all the staff members assess the clinical details provided in a consistent and standardised fashion. This has involved a lot of protocol development and these protocols are still in a process of evolution. For example “Erythema and increased pain leg ulcer” are acceptable details whilst “chronic leg wound” is not, and then there is the myriad of word variations in between. It is not straightforward!

Although most of the clinicians have been supportive of such a policy and indeed have embraced it by including excellent clinical details, there remains a small cohort who refuse to believe that the inclusion of clinical details on microbiology request forms is important. There are a few others that believe in the policy in principle but have concerns over the logistics.

The goal over the next year or so will be to continue to build a clinical details culture amongst clinicians so that clinical information on microbiology forms (and all laboratory request forms) is the expected norm. This represents a positive step for all the involved stakeholders; clinicians, laboratory staff and patients alike.

Along the same lines I hope that many other diagnostic microbiology laboratories both nationally and internationally adopt a similar stance. The presence of clinical details is a key element of effective diagnostic stewardship. Without them, you are already on a hiding to nothing…

Michael