Issued: Wednesday 7th July 2010
We have been alerted to a possible problem with reagents that we use to determine the susceptibility of ciprofloxacin for bacteria cultured from specimens submitted to the Medical Microbiology Laboratory at St George’s Healthcare NHS Trust. An error was detected by the manufacturers some months after they had distributed the reagents to diagnostic laboratories worldwide and therefore they had been widely used. The error means that some microbiology results issued by our laboratory could indicate that an organism was sensitive to ciprofloxacin when in fact it could be resistant.
Our own in house quality control programme did not indicate that the reagents supplied to us were in any way at fault, but we cannot be absolutely certain of this. Therefore, I we are advising that some patients who were prescribed ciprofloxacin for an apparently sensitive organism may not have been adequately treated.
The time period is 3rd February 2010 to 26th March 2010 and all specimen results for ciprofloxacin sensitivity, with the exception of results for Neisseria gonorrhoeae, Pseudomonas sp and Salmonella typhi/paratyphi, could be affected. Results for all other antibiotics are correct.
Although we test many organisms for ciprofloxacin susceptibility, in recent years our practice has been to suppress the ciprofloxacin result for the majority in an attempt to limit the use of ciprofloxacin. Therefore, we anticipate that the number of patients who were actually prescribed ciprofloxacin on the basis of a result would be very small indeed.
If you have questions about the above and, in particular, any specific patient results that you need to discuss please call Peter Riley, Consultant Medical Microbiologist, on 020 8725 5707 or email firstname.lastname@example.org.