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b After 1 year of follow-up, patients on HAART with a baseline viral load (VL) of <20 copies/ml showed significantly lower odds of virological rebound to two consecutive VLs of >50 copies/ml than those with baseline VLs of 20 to 39 and 40 to 49 (P < 0.001). The time to virological rebound was also significantly shorter (P < 0.001) for the groups with baseline VLs of 20 to 39 and 40 to 49. T he number of patients failing antiretroviral treatment with low-level viremia (e.g., a viral load [VL] ranging from 40 to 1,000 copies/ml) is increasing (1, 2), and special interest has been shown in the clinical significance of this finding. During the last years of the past decade, commercial assays for measuring viral loads reduced their detection limits (3-6), which shifted from 50 to 40 to 20 copies/ml, depending on the assay (7). Recently, a number of reports (8-12) have focused on the clinical significance of very low-level viremia (e.g., viral-load levels below 20 or between 20 and 50 copies/ml). The use of different assays or a different sample size, and even different baseline characteristics of the studies, may partially explain some of the contradictory findings of the studies. In addition, high variability of the Cobas Ampliprep/Cobas TaqMan v2.0 assay at levels of 20 and 40 HIV copies/ml has been described (13).Since the introduction in our institution of Cobas TaqMan v2.0 (Roche Diagnostics) in June 2009, the lower detection cutoff of 50 copies/ml was shifted to 20 copies/ml, and this new threshold was reported to physicians treating HIV and thus used for making clinical decisions.In this retrospective cohort study, we have investigated the clinical significance of having a viral load between 20 and 50 copies/ml in terms of the odds for a viral-load rebound to more than 50 copies/ml or 400 copies/ml 1 year after testing. When possible, the emergence of resistance was also investigated.All adult HIV patients (Ͼ18 years old) who were on highly active antiretroviral therapy (HAART) with an available follow-up 12 months (median, 12.42 months; interquartile range [IQR], 11.73 to 13.80 months) after a viral-load test result below 50 copies/ml (time zero [T 0 ]) using the Cobas TaqMan v2.0 assay were included. When needed, resistance testing of very low-level viral loads was performed using a concentration step (14) prior to following the standard procedure of the Trugene HIV genotyping kit (Siemens NAD). Two hundred ninety patients met the inclusion criteria, and the pre-T 0 CD4 count, time (in years) with a VL of Ͻ50 before T 0 , number of years on HAART, and type of HAART regimen were retrieved from their medical records. Virological rebound was considered when two consecutive viral loads were recorded. Two definitions of virological rebound were evaluated: (i) rebound to more than 50 copies/ml, confirmed in two consecutive samples, and (ii) rebound to more than 400 copies/ ml, also confirmed in two consecutive samples. The time to virological rebound in months was also recorded. The baseline characteristics were ...

Objectives To assess the attitudes and opinions about generic antiretroviral drugs (ARVs) and single-tablet regimen (STR) de-simplification among physicians prescribing HIV treatment in the cohort of the Spanish HIV/AIDS Research Network (CoRIS). Methods An online questionnaire with 27 structured questions was sent to all physicians (n = 199) who prescribed ARVs among the 45 centres participating in the cohort. Results A total of 169 (84.9%) physicians answered the questionnaire. Only 4.1% of the physicians would never prescribe generic ARVs, but 53.3% would not prescribe them if the number of pills per day increased and 89.3% would not prescribe them if the number of doses per day increased. However, 84.0% of the physicians agreed to prescribe generic ARVs if doing so would decrease costs for the public healthcare system. The percentages of physicians stating that generic ARVs (compared with branded ones) would be associated with worse adherence, more adverse effects or more probability of virological failure, provided that the number of pills and doses per day would not change, were low: 0.6%, 7.7% and 3.6%, respectively. However, these percentages were much higher if the generic ARV entailed breaking an STR: 63.9%, 18.9% and 42.0%, respectively. Most physicians stated that they needed more information about the effectiveness and safety of generic ARVs and the price difference compared with their branded equivalents. Conclusions Although most physicians were confident about prescribing generic ARVs, the majority had strong concerns about de-simplifying STR, and they also needed more information about generic drugs.

Fever of intermediate duration (FID) is a new nosologic entity defined as fever higher than 38 degrees C that has a duration of between 1 and 4 weeks and that after an initial approach has not been diagnosed. It has clinical similarities with fever of unknown origin, but because of characteristic etiologies it requires the term FID. We describe the clinical characteristics and etiology of FID in the south of Spain and create a treatment algorithm. Retrospective study of the medical charts of patients attending at our Service during 2000 and 2005 who had an initial diagnosis of FID and who had a complete follow-up until the resolution of symptoms. Two hundred and thirty-three patients met the inclusion criteria, of whom 164 were men. Median number of days before being referred to our service was 9 (range 2-28). Half of the patients had elevation of transaminases, and CRP and ESR were slightly elevated, 2.8 mg/dl (range 0.1-50) and 16 mm/h (range 1-131) respectively. A final diagnosis was made in 80 patients, with infection with coxiella (32 patients), CMV (16 patients), rickettsial species (11 patients), VEB virus (6 patients), and brucella (5 patients) being the more frequent entities. Doxycycline was the antibiotic most frequently prescribed. Among patients with Q fever, CMV, and rickettsial infection, the majority had abnormal hepatic function, (87%, 93%, and 55% respectively). In FID, a diagnosis is reached in a minority of patients, although the prognosis is excellent in most of them. In our patients the clinical picture of Q fever, CMV, and rickettsial infections included abnormal hepatic function. In addition, these three infections are the most frequently diagnosed so when treating a patient with FID, if elevation of liver enzymes is present patients should start on doxycycline.

No abstract