Misdiagnosed with a STI and not told it could be a false positive result
23. We first look at whether there are signs the organisation has got something wrong. We do this by comparing what should have happened with what did happen. We use the relevant standards and guidance to say what should happen. We then go on to consider all versions of events. If we find something went wrong and it fell below a standard, we refer to this as a failing.
24. Next, we look at if the failing had an impact and if so, what an organisation has done to put this right. If we think more can be done, we may make recommendations to the organisation.
25. The Public Health England Guidance for the detection of gonorrhoea in England is the relevant guidance to tell us what should have happened in this situation. This says:
‘Section 2.8 Issuing test results
• Diagnostic samples should be processed promptly so that results can be conveyed within an acceptable time frame. Laboratories should only issue positive test results that are confirmed by supplementary testing, or where the PPV of the initial test has been validated by the laboratory as being above 90%.’
26. Positive predictive value (PPV) represents the probability that a person has a disease or condition given a positive test result. That is, it is the proportion of individuals with positive test results who are correctly identified or diagnosed. The guidance says a result should only be given when it is 90% or above certain.
27. The guidance does not say patients receiving a positive test result in any setting should be advised it could be a false positive result. This is not a requirement.
28. It does require that supplementary (extra) testing should be carried out for a positive test result where the PPV of a positive result is low, such as a test done in a general practice. Where the PPV of a true positive test is over 90% such as in a sexual health clinic, then it is not necessary for a supplementary test to be taken to support a positive test result.
29. Mr L was tested in a sexual health clinic which meets the requirement of the guidance for issuing a result without a supplementary (second) test because it was checked by a validated laboratory.
30. Mr L says after receiving the positive test result on 11 February, he attended a follow-up appointment at the Trust on 15 February for antibiotic treatment. Mr L says he told the clinicians at the time he did not feel he had the infection and asked if he could have another test to check the results. Mr L says this was agreed and he had another test, but he felt the clinicians pressured him into taking the antibiotics.
31. Mr L says he got the results from the second test on 18 February and they were negative. On 21 February he spoke with a health advisor on the phone about the distress the false positive result had caused him, his concern he had unnecessary antibiotic treatment and the breakdown of his relationship with his partner. Mr L says he told the health advisor about his intention to make a formal complaint because he was not told that his test result could have been false.
32. The Trust’s complaint response explained that a test for gonorrhoea identifies RNA (a small part of the bacteria's genes) and it is extremely sensitive. In most cases, it is a reliable test but there is the risk of a small possibility of a false positive test but the rate of these varies according to the population being tested.
33. It said a review of Mr L’s medical record did not show that any of the health professionals he saw at the time explained that false positive results can happen when testing for gonorrhoea. The Trust said it accepted that having this explained to him may have changed Mr L’s decision about having treatment and how he discussed the result of his first test with his partner. The Trust apologised and said this had been fed back to the service to make sure it learned from this and used the learning in future consultations with patients who have tested positive for gonorrhoea.
34. We understand the reliability of a test will depend on the likelihood of the population being tested having the disease being tested for. So for example, if tests for a specific disease in a general population where the prevalence is very small (one in a million) then it is more likely that a positive result is incorrect (false positive), than if tests on a population where the specific disease is more common (one in a hundred), where a positive result is more likely to be a true result. Because the people who attend a sexual health clinic are more likely to have gonorrhoea than the population in general, it would mean the PPV of a test is likely to be over 90%.
35. We asked the Trust if the clinic has any data on how accurate its testing is and if the PPV is over 90% for gonorrhoea testing. The Trust explained the manufacturers of the test kit does not give a PPV, but they give a specificity on testing negative samples of 98.3 - 100%. The specificity of a test is its ability to find an individual who does not have a disease as negative. A highly specific test means that there are few false positive results.
36. The Trust said cross-contamination between samples can cause a 'false positive' when there are strongly positive samples on the same run as negative samples. The test manufacturer says this type of cross-contamination can happen at a rate of 0.5%.
37. We have seen the medical records and it is noted that Mr L spoke to a doctor saying he did not think he had the infection, but he would take the medication ‘to be on the safe side’. We have not found any evidence of Mr L being pressured into taking the medication.
38. From the evidence available we have found the Trust acted in line with the Public Health England guidance. There is no requirement for a patient to be told a false positive result may be possible. The guidelines say laboratories should only issue positive test results that are confirmed by supplementary testing, or, in Mr L’s case, where the PPV of the first test has been validated by the laboratory as being above 90%.
39. As we know the PPV of the Trust’s sexual health clinic is over 90% (as defined by the manufacturers interval 98.3 - 100%) it was appropriate to issue the positive test result to Mr L on 11 February. The guidelines do not say people being tested must be told of the possibility of a false positive when issuing a positive test result. There was no obligation on the Trust to discuss this with Mr L. But, we are pleased to note the Trust has adopted this approach to use in future consultations with patients who have tested positive for gonorrhoea.
40. We are sorry to learn about the impact the false positive result had on Mr L’s relationship with his partner, we recognise this was deeply distressing for him. We do not think the Trust is responsible for how this personal issue was approached and dealt with by Mr L and his partner.
41. Having considered all the evidence, we have not seen any failings in the care and treatment provided to Mr L in February 2022 and we have decided to take no further action on this complaint.
Complaint handling delays
42. The NHS Complaints Regulations tell us what should have happened. Section 14 of this guidance says an organisation must send the complainant a response within six months of it getting the complaint. If the organisation does not send a response within this period, it must:
• tell the complainant in writing and explain the reason for delay • send the response in writing as soon as possible after the expected six-month period.
43. Mr L sent a formal complaint to the Trust on 25 May. We can see the Trust responded to this complaint fairly quickly on 23 June. But, as Mr L was not happy with the response, he escalated his complaint to stage two on 30 June and the Trust acknowledged the complaint on 6 July.
44. Mr L contacted us on 28 November as he had not received a response from the Trust to his stage two complaint. We sent an enquiry to the Trust on 2 and 19 December asking when Mr L would get a response to his complaint.
45. On 9 January 2023 we contacted the Trust again and it sent its final response letter to Mr L dated 19 January. We can see the Trust apologised for the delay.
46. Though there is no guarantee to complaint handling times, in line with the NHS Complaint Regulations, Mr L should have had a response to his second complaint by 30 December (around six months from date submitted). There was a delay of around three weeks outside this period and we have seen no evidence that the Trust contacted Mr L in writing to explain the reasons for the delay.
47. Our Principles explain that we look into complaints where someone believes they have been negatively affected because an organisation has not acted properly or has given a poor service and not put things right.
48. Where we find this is the case, we consider whether an organisation has already taken appropriate action to try to resolve the complaint. If we find an organisation has not, we will usually make fair recommendations on how they can do this. This will not always include suggesting a financial payment is made.
49. Here we have found there was a failing as the Trust did not respond to Mr L’s second complaint in line with the NHS Complaint Regulations. But we note these regulations also explain what should happen when a complaint goes beyond six months. Complaint handling can vary in time depending on the nature of complaint, complexity and the departments involved.
50. We recognise Mr L was frustrated when waiting for a response from the Trust and he was inconvenienced in contacting us to try to speed things up. The slight delay of just under three weeks in completing caused a low level of injustice.
51. Mr L wants a payment to put this right.
52. Our guidance on financial remedy includes a severity of injustice scale. We use this to decide on how seriously someone was affected by what happened. The scale has six bands ranging from minor frustration (level one) to more serious life changing or profound severity often resulting in disability or death (level six).
53. A case will generally be low level if we consider the person affected has experienced a low impact injustice such as annoyance, frustration or worry or inconvenience typically caused by a single (one-off) incidence of fault. The effect on the person complaining is of short duration and there are no other negative effects or ongoing wider impact.
54. Here, we have found this to be a few weeks over six months in complaint handling and not a situation where a failing has caused financial disadvantage. We consider this sits at around level one of the scale. At this level we will usually consider an apology to be an appropriate way to put things right.
55. We can see the Trust apologised for the delay in complaint handling and we think this is in line with our Principles and the severity of injustice scale. We have decided the Trust does not need to do anything more.