Adults with tuberculosis (TB) in the UK should have an HIV test offered and recommended, according to a senior public health physician speaking at a conference on HIV and TB in London on March 24th.
Dr Barry Evans of the Health Protection Agency presented data showing that TB has drawn level with PCP pneumonia as the most common AIDS-defining illness in the UK. In 2003 a total of 178 new cases of PCP were diagnosed in HIV-positive individuals, comprising 28% of all AIDS diagnoses, with 167 new cases of TB diagnosed, contributing 27% of all AIDS diagnoses.
Problems with under-reporting and misdiagnosis probably mean that many cases of TB in HIV-positive patients go unrecorded, noted Dr Evans, who estimated that 30% of TB cases in HIV-positive patients were not recorded on the Health Protection Agency’s TB database. Nevertheless, on available data the Health Protection Agency estimated that of all HIV-positive individuals in the UK, 3.7% had TB, and that 2.7% of all TB cases in the UK involved patients infected with HIV.
Data also revealed that TB had a distinct impact on different communities and age groups. According to Dr Evans, only six HIV-positive gay men were diagnosed with TB in 2003, with nearly all the remaining diagnoses in HIV-positive individuals made in people from Africa.
Nearly all cases of TB in HIV-positive patients (99.6%) were diagnosed in individuals aged between 15 - 64 years.
On the basis of these data, Dr Evans suggested that all adult patients aged between 15 and 64 diagnosed with TB should be offered and recommended an HIV test.
The importance of diagnosing TB in HIV-positive patients was emphasised by Dr Evans, who noted that the median CD4 cell count of HIV-positive patients diagnosed with TB was 100 cells/mm3. “These people need TB medicines and they need HAART,” said Dr Evans, adding, “the only way to get them HAART is to make sure their HIV is diagnosed.”
Experience from offering universal antenatal HIV tests showed that offering and recommending HIV tests to all TB patients was practically possible, concluded Dr Evans.
TB still causing death in HIV-positive patients without being diagnosed
Data was also presented to the conference which showed that clinicians were often failing to diagnose TB in HIV-positive patients. Professor Sebastian Lucas of St Thomas’s Hospital in London presented a case series involving 200 HIV-positive patients who he had performed autopsies on between 1994 and 2004. Ten of these individuals had died of TB without it first being recognised before death, showing that TB was being missed even in patients with severely damaged immune systems. Prof Lucas suggested that his case study showed that there was a role for empirical therapy for patients with advanced immune damage whose symptoms could be suggestive of TB.
The conference was also told that, like HIV, there were approximately 7,000 new TB cases a year diagnosed in the UK, and that, again like HIV, TB caused 400 deaths a year.
Further information on this website
Tuberculosis - overview
Evans B. HIV and TB across the UK. TB: HIV’s most constant companion, Royal Society of Medicine, March 24th 2004.
Lucas S. The pathophysiology of TB and HIV. TB: HIV’s most constant companion, Royal Society of Medicine, March 24th 2004.