“To commercialise a dipstick method to exclude UTI is a blunder attributable to the base rate fallacy: Making a judgment without considering the prior probabilities.
To do so, despite world literature on dipstick artifice, is to bungle badly.”

(https://mobile.twitter.com/JamesMaloneLee3/status/1154694034...)

This is dangerous. Dipstick testing CANNOT exclude UTI. This service relies on an outdated testing protocol and reliance on this test risks harming significant numbers of patients. (start here: http://www.cutic.co.uk/patients/gp-information-sheet/). Up to 50% of dipstick tests, and 50% of urine cultures, miss the infection, and with this service a negative test would be assumed to indicate no infection. Professor James Malone-Lee of University College London has published extensively about the failings of current urine testing and how this can lead to chronic debilitating bladder disease being missed. For example, from a presentation he made to the UK Parliament:

“The betrayal of the cystitis sufferer”

Urinary tract infection (cystitis / UTI) affects 150 million people worldwide each year: 33% of women are expected to suffer before they are 24.

Women presenting with symptoms of UTI in primary care will be managed according to a guideline, there are several of these; they are contradictory and most ignore the published science.
...
Many practices will test the urine with dipsticks and, if these prove negative, the patient is informed that there be no infection. This is incorrect advice and confuses no evidence of disease with evidence of no disease. The dipstick test will miss well over 50% of all infections.

If a urine sample is sent to the laboratory for culture, and this is reported as negative, it is probable that this will be assumed to refute the diagnosis of UTI. This is also wrong; the standard MSU culture will also miss well over 50% of all infections, so that a negative test is not evidence of no disease.

If the patient is fortunate enough to be diagnosed with a UTI it is possible that she may be prescribed antibiotics, typically for three days. This may not work: 20% to 30% of patients will fail recommended treatment whether prescribed for three days or 14 days. If she complains that she has not recovered is likely to be dismissed: She will have been advised to drink plenty, her urine, suitably diluted, will be devoid of pathological signals. Thus it is assumed that she must be better – The test says so.

These facts have been available in the scientific literature for a large number of years. The standard guidelines seem to ignore this evidence placing people at risk of being denied appropriate treatment. We do not know the consequences of untreated UTI persisting over months or years, but it may reap harm. The current anxieties about antibiotic resistance make it harder to bring sober reflection to this problem.

This may be an orphan subject but a cause of immense suffering for many people

James Malone-Lee MD FRCP
Professor of Medicine, Whittington Campus, UCL Medical School
6th July 2016”

Various interesting papers on the subject:

https://www.ncbi.nlm.nih.gov/pubmed/25949979?dopt=Abstract
Reliability of dipstick assay in predicting urinary tract infection.
“Nitrite test and leukocyte esterase test when used individually is not reliable to rule out UTI.”

A blinded observational cohort study of the microbiological ecology associated with pyuria and overactive bladder symptoms
https://link.springer.com/article/10.1007%2Fs00192-018-3558-...
“In this study, routine laboratory culture did not differ between patients and controls at any stage. It is worrying that the gold standard diagnostic test cannot discriminate patients from controls, despite other measures showing clear, consistent, inflammatory and microbiological differences.”

https://link.springer.com/article/10.1007/s00192-018-3569-7
Recalcitrant chronic bladder pain and recurrent cystitis but negative urinalysis: What should we do?