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Updated: May 27, 2026

Amplifying and Quantifying HIV-1 RNA in HIV Infected Individuals with Viral Loads Below the Limit of Detection by Standard Clinical Assays
Published on: September 26, 2011
Late presenters, repeated testing, and missed opportunities in a Danish nationwide HIV cohort
Marie Helleberg1, Frederik N Engsig, Gitte Kronborg
1Department of Infectious Diseases, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark. mhelleberg@sund.ku.dk
Background:
We aimed to estimate the incidence and predictors of late presentation among human immunodeficiency virus (HIV)-infected individuals in Denmark.
Methods:
Incidence rates (IR) of presentation with advanced HIV (CD4 < 200 cells/μl and/or acquired immune deficiency syndrome (AIDS)) and late presentation (CD4 < 350 cells/μl and/or AIDS) were calculated per 100,000 population aged 16-60 y. Mortality rate ratios (MRR) were estimated using Poisson regression analysis.
Results:
Three thousand and twenty-seven individuals were diagnosed with HIV in 1995-2009; 34.7% presented with advanced HIV and 51.2% were late presenters. The IR of HIV was stable (6.2/100,000 population), but IR of presentation with advanced HIV declined during the study period from 2.2 (95% confidence interval (CI) 1.8-2.8) to 1.1 (95% CI 0.8-1.5). Age >50 y, heterosexuals of non-Danish origin, 'other' route of transmission, and diagnosis before 2002 were associated with an increased risk of presenting with advanced HIV, whereas a negative HIV test prior to diagnosis was associated with a significantly reduced risk. A total of 414 individuals (40.0%) had attended a hospital 1-3 y before presenting with advanced HIV. After 2002 the proportion of men who have sex with men with a negative HIV test prior to diagnosis increased (incidence rate ratio (IRR) 1.3, 95% CI 1.1-1.6), coinciding with a reduction in IR of presentation with advanced HIV. Mortality rates were increased the first 2 y following presentation with advanced HIV (MRR 5.9, 95% CI 3.6-9.4 and MRR 2.5, 95% CI 1.4-4.1, respectively).
Conclusion:
In a setting with a low HIV prevalence, the rate of presentation with advanced HIV can potentially be reduced by repeated HIV testing of individuals with a continuous high risk of transmission and by adhering to guidelines for targeted HIV testing.
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