Boric acid urine collection tubes

We are changing the way we receive urine cultures from you. We have now transitioned to the BD Vacutainer and Sarstedt Monovette for urine microscopy and culture. From Monday 9 November, urine samples being sent for culture should only be submitted using either of these approved consumables.

BD Vacutainer: This system includes a collection cup with a built-in transfer device and a tube containing boric acid.

Sarstedt Monovette: Urine is collected in a separate collection cup, then transferred into the tube containing boric acid. We recommend using a sterile plain white universal container as the collection cup.

The change is being made to improve the quality and safety of the urine testing pathway for patients. Boric acid is essential for accurate urine culture results. Without it, urine culture has many more false-positive and non-clinically significant results. Using the approved containers will help to ensure turnaround times are met, reduce the risk of transcription errors and reduce the need for patients to provide repeat samples.

Both systems are available to order. Please:

• Ensure all relevant staff are aware of the change.
• Switch to one of the approved systems before 9 November 2026.
• Use up remaining red-topped boric acid universal containers before this date and stop ordering them.

Continue using plain white universal containers for other urine tests, such as Albumin Creatinine Ratio (ACR).

Boric acid tubes must not be used for chemistry or immunology tests, as the preservative can make samples unsuitable for analysis.

Instructions and patient leaflets

• BD Vacutainer patient instructions
• Sarstedt Monovette instructions

When a universal white top tube is received, it must be manually decanted into a suitable tube which has to be relabelled. The current high proportion of these means that this manual intervention can take an additional few hours, which delays both a negative microscopy report and the commencement of the culture incubation period.

When a green topped tube is received in the lab, it goes straight onto the analyser for microscopy screening and the results of this are available for review by lab staff within 15 minutes.

If the microscopy parameters fall under the thresholds for onward culture, the negative report is issued and can be sent out by the following morning, if not later the same day. If microscopy is needed, the sample is sent for culture straight away.

This means that results are available to requesting clinicians faster, allowing for any patient treatment to be started sooner, which we believe is a clinical improvement.

Samples received in boric acid tubes are significantly more stable than if they are in a plain white top universal tube. In the event of a service disruption, the incidence of sample cancellation is very small. Also, with no preservative the sample can be prone to bacterial overgrowth.

We’re aware of concerns that both systems require a collection cup and therefore appear to introduce an additional piece of single-use plastic.

Urine samples were already being decanted into smaller analyser tubes in the laboratory, so a second consumable has always formed part of the urine culture process, although this would not previously have been visible to service users.

We remain committed to reducing our carbon footprint wherever possible, while working within infection control requirements.

We did a survey of what other Pathology Services use across London Boroughs. Both Southwest London (St George’s) and East-Southeast London (Barts and the Royal London, which also includes LGT) Pathology use a vacutainer type tube and associated cup, and NW London (Charing Cross/St Mary’s) have a pouring cup and screw top tube combo.

If practice colleagues and patients are unable to dispose of the container lid safely, they can include only the container lid with their sample and Synnovis will dispose of it for them.

From Monday 9 November, we will no longer process urine culture samples that are not received in one of the two approved tubes.

Patient and staff safety was a key consideration in evaluating the BD Vacutainer system. The needle element is contained within the blue lid in a protected housing and covered by a warning label. The patient instructions, which advise against contact with the housing, explain how to reseal the opening after transfer and ask patients to return the blue lid with the sample so that Synnovis can manage its disposal safely.

Regarding health and safety, a formal risk assessment of the BD collection cup lid and transfer mechanism was completed before implementation. The transfer system incorporates protective features, patient guidance has been developed, and patients are instructed to return the blue lid with the sample for safe disposal by Synnovis. We feel assured that the BD system has been successfully introduced and is currently being used by practices in ESEL and SWL ICB regions.

We will continue to review the arrangements as part of implementation and respond to any safety concerns identified in practice.

We recognise that some clinicians will wish to perform dipstick analysis before deciding whether a sample requires laboratory submission. Where a sample is produced in the surgery, the original collection vessel remains available for this purpose. With the BD system, dipstick testing can also be undertaken from the boric acid tube by removing and replacing the green cap.

We considered the concern that transfer through the BD device could damage red cells and affect microscopy, including assessment of microscopic haematuria. Our current clinical assessment is that this does not represent a material risk: the transfer system is relatively wide bore, and the process does not subject the urine to forces that could cause haemolysis like those seen with poorly performed phlebotomy.

However, we agree that this specific point should be supported by definitive technical evidence. We have therefore asked the manufacturer to provide formal evidence regarding red-cell integrity during transfer and will share the relevant information once received.

For questions about the change, contact Synnovis Customer Services:

• Telephone: 020 4513 7300
• Email: customerservices@synnovis.co.uk