A significant proportion of patients at a major London HIV treatment centre are diagnosed with HIV with very low CD4 cell counts, according to a study published in the November 5th edition of AIDS. The investigators also found that individuals presenting with late-stage HIV infection were more likely to be women, of African ethnicity and older.
There have been anecdotal reports that the number of individuals being diagnosed with HIV in the United Kingdom when they already have severe immune suppression has increased in recent years. Patients who have a low CD4 cell count at the time of their HIV diagnosis are at higher risk of disease progression and are less likely to experience the same degree of immunological and virological benefit from HAART. There are also concerns individuals who have very low CD4 cell counts at the time of their HIV diagnosis make a greater demand on clinical services.
Investigators from the Royal Free Hospital in north London wished to determine the characteristics of patients diagnosed with a CD4 cell count below 50 cells/mm3. They also wished to see if there had, in fact, been an increase in late diagnosis in recent years, to describe the clinical outcomes of late presenters and to describe the uptake of HAART and the resulting immunological and clinical benefits.
The medical records of all patients diagnosed at the centre between January 1996 and the end of 2002 were examined. In total 719 patients were diagnosed with HIV at the Royal Free Hospital during this period, the median CD4 cell count being 320 cells/mm3. Of these patients, 110 (15%) had a CD4 cell count below 50 cells/mm3 at the time of their diagnosis.
Severe immune suppression at the time of HIV diagnosis was associated with female sex (p = 0.03), older age (p
Although the proportion of patients diagnosed with severe immune suppression increased from a little over 10% in 1996 to just under 19% in 2002, this increase was not statistically significant (p = 0.49).
As would be expected with such severe immune suppression, over 50% of patients with a CD4 cell count below 50 cells/mm3 had an AIDS-defining condition at the time of their diagnosis. This compared to only 7% of patients diagnosed with HIV at higher CD4 cell counts (p
Antiretroviral therapy was started by 99 (90%) of late presenters with the median time from diagnosis to the start of therapy being 22 days.
In total eleven patients did not start antiretroviral therapy and eight of these individuals died within three months of their HIV diagnosis. A further patient died after nine months.
Of the patients who did start HAART, 87 (88%) achieved a viral load below 400 copies/ml within a median time of 83 days. Viral load rebounded to above 400 copies/ml in 17% of patients after one year and 19% after two years of treatment.
After two months of HAART the CD4 cell count increased from 43 to 204 cells/mm3.
A total of 38 AIDS-defining events were diagnosed in 30 patients. The most common conditions diagnosed were tuberculosis (seven cases), Pneumocystis pneumonia (PCP; six cases), cytomegalovirus (CMV; six cases), toxoplasmosis (four cases) and wasting syndrome (four cases).
At least one follow-up appointment was attended by 68% of patients. There were 73 separate in-patient admissions with the total number of in-patient days being 1710. Each stay as an in-patient had a median duration of 23 days. In-patient stays were most likely to occur during the first three months following diagnosis, levelling out thereafter.
“A significant proportion of patients diagnosed with HIV in each year at our centre have a very low CD4 cell count,” write the investigators. “These patients commonly present with multiple AIDS conditions, place major demands on hospital resources…and in some cases prognosis is poor.”
The investigators also note that patients presenting with very low CD4 cell counts come from disadvantaged groups, notably African women. They conclude, “continued attempts to increase early testing and to improve awareness of HIV among general practitioners and hospital doctors, who may well treat these individuals prior to their HIV diagnosis, are essential.”
Sabin CA et al. Late presenters in the era of highly active antiretroviral therapy: uptake of and response to antiretroviral therapy. AIDS 18: 2145-2151, 2004.