Routine tests prompted by electronic patient records increase rates of STI diagnoses among HIV-positive people in London

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The implementation of systematic, frequent and routine screening for sexually transmitted infections (STIs) led to a significant increase in the number of infections detected among HIV-positive people in London, investigators report in HIV Medicine. Doctors and nurses caring for HIV-positive people were prompted to carry out an annual STI screen by an electronic patient records system.

Many of the detected infections were asymptomatic. Incidence of chlamydia, gonorrhoea and syphilis all increased significantly in gay men, and there was a significant increase in incidence of chlamydia and trichomonas vaginalis among heterosexual people.

“Although some of these increases may be attributable to a genuine increase in STI incidence, it is likely that better diagnosis is responsible as a result of the introduction of prompts on our EPR [electronic patient records] system to aid more systematic STI screening,” write the authors.



Chlamydia is a common sexually transmitted infection, caused by bacteria called Chlamydia trachomatis. Women can get chlamydia in the cervix, rectum, or throat. Men can get chlamydia in the urethra (inside the penis), rectum, or throat. Chlamydia is treated with antibiotics.


A sexually transmitted infection caused by the bacterium Treponema pallidum. Transmission can occur by direct contact with a syphilis sore during vaginal, anal, or oral sex. Sores may be found around the penis, vagina, or anus, or in the rectum, on the lips, or in the mouth, but syphilis is often asymptomatic. It can spread from an infected mother to her unborn baby.

person years

In a study “100 person years of follow-up” could mean that information was collected on 100 people for one year, or on 50 people for two years each, or on ten people over ten years. In practice, each person’s duration of follow-up is likely to be different.

lymphogranuloma venereum (LGV)

A sexually transmitted infection that can have serious consequences if left untreated. Symptoms include genital or rectal ulcers.


The study of the causes of a disease, its distribution within a population, and measures for control and prevention. Epidemiology focuses on groups rather than individuals.

Early detection and treatment of STIs in people with HIV is important for two reasons: untreated infections increase the risk of HIV transmission, even when someone is taking virologically suppressive therapy; and some STIs, including syphilis and hepatitis C, can be harder to treat in people with HIV.

Guidelines recommend that regular STI screens should be incorporated into routine HIV care. Audits of clinical practice in the UK and elsewhere suggest that screening often does not occur, with testing rates as low as 46%.

Since 2008, hospitals in north-west London have been using electronic medical records for their HIV-positive patients. This includes an annual checklist, prompting healthcare professionals to undertake certain investigations, including an annual STI screen.

Investigators wished to see how successful they had been at diagnosing STIs in HIV-positive patients since the introduction of the checklist.

They therefore designed a retrospective study involving approximately 900 patients who received care between 2009 and 2012.

Data were gathered on STI incidence in three concurrent twelve-month periods: 2009/10; 2010/11; 2011/12.

From the electronic records, the investigators were able to establish that 90% of patients had an STI screen in 2009/10. This increased to 97% of patients in 2010/11.

The total number of people diagnosed with an STI was 19 in 2009/10. This increased to 21 in 2010/11 and almost doubled to 41 in 2011/10.

Infection rates in all three time periods were significantly higher among gay men than in heterosexual people (p < 0.05).

In 2010/11, a total of 7 chlamydia infections were diagnosed in gay men. This doubled to 14 in 2011/12 (p < 0.001), and nine of these infections were asymptomatic. The 100% increase in chlamydia infections detected by the investigations was significantly higher than the 10% increase seen among gay men nationally.

Diagnoses of gonorrhoea also more than doubled in gay men between 2010 and 2012, from 5 to 12 infections (p < 0.05), 50% of which were asymptomatic. The investigators note that this increase in gonorrhoea incidence outstripped the 10% annual rise seen in national surveillance data.

Diagnoses of early syphilis also increased significantly from 4 to 13 infections (p < 0.0001). This increase was against national trends, and the investigators suggest that their findings are therefore likely to reflect local epidemiological conditions. However, they believe their screening programme meant that diagnoses were made “several months earlier than would have happened previously and may have prevented progression to late stage disease”.

The use of the checklist did not lead to an increase in the number of LGV infections diagnosed in gay men. Only two infections were detected; one was asymptomatic, the other had mild symptoms. Most LGV infections involve symptoms and it is therefore possible that proactive screening led to the detection of infections which may otherwise have remained undiagnosed.

“Another benefit of advanced screening is that the anus is examined more frequently in a group of men at higher risk of anal cancer,” comment the investigators.

The use of the electronic checklist led to an increase in the detection of chlamydia infections among heterosexuals (2010/11 = 4 vs 2011/12 = 13; p < 0.0001). Over the course of the study, incidence of trichomonas vaginalis among heterosexual patients increased from 0.1 per 100 person-years to 0.4 per 100 person-years.

“With a systematized approach to STI screening using facilities inherent in EPR, we have dramatically increased the rate of STI diagnoses in both MSM and heterosexual patients,” conclude the authors.


Brook G et al. Retrospective study of the effect of enhanced systematic sexually transmitted infection screening, facilitated by the use of electronic patient records, in an HIV-infected cohort. HIV Med, online edition. DOI: 10.1111/hiv.12020, 2013.