D.C. Cibelli

Co-receptor switch during HAART is independent of virological success.

The influence of antiretroviral therapy on co‐receptor tropism remains controversial. To verify if co‐receptor tropism shift was affected by HAART, the evolution of proviral DNA V3 genotype after 12 months of a new antiretroviral regimen was compared between responder and non‐responder patients. Baseline blood samples were collected from 36 patients infected with HIV‐1 subtype‐B (18 naïve and 18 experienced) for virus isolation and env V3 genotyping from plasma HIV‐1 RNA and PBMC DNA. DNA V3 genotyping was repeated after 12 months from initiating HAART. WebPSSM was used for categorizing V3 sequences into X4 or R5; for analysis purposes, dual/mixed viruses were considered as X4. From the 10 (28%) patients changing their proviral DNA V3 genotype during therapy, six shifted from R5‐to‐X4 and four from X4‐to‐R5. The lack of reaching virological suppression was not associated with an X4‐to‐R5 (P = 0.25) or R5‐to‐X4 (P = 0.14) shift; time‐to‐viral suppression and CD4 increase were similar in both groups. No association was found between tropism shift and patient baseline characteristics including age, sex, CDC stage, CD4 count, viral load, exposure and length of previous HAART, enfuvirtide use in the new regimen, number of reverse transcriptase and protease resistance‐associated mutations. Conversely, CD4 nadir was correlated to emergence of X4 virus in proviral DNA (mean 27.2 ± 30.6 in R5‐to‐X4 shifting patients vs. 161.6 ± 150.6 in non‐shifting patients, P = 0.02). The occurrence of a tropism shift in both directions was independent of HAART use, irrespective of its efficacy. The CD4 count nadir was the only baseline characteristic able to predict an R5‐to‐X4 viral shift. J. Med. Virol. 81:2036–2044, 2009.

Prevalence of HBV-genotypes in immigrants affected by HBV-related chronic active hepatitis

BACKGROUND The genetic heterogeneity of the HBV genome has been established and eight genotypes can be classified according to the criterion of >8% differences in the complete nucleotide sequence of the viral genome. AIMS To evaluate the prevalence of HBV-infection in a population of immigrants and to determine in patients with detectable serum HBV-DNA the HBV-genotypes. METHODS Between January 2005 and December 2005 a total of 556 immigrants were tested for HBsAg. In HBsAg positive patients the biochemical and virological activity of infection and the possible presence of co-infections (HCV, HDV, HIV) were evaluated. In patients with detectable serum HBV DNA, the HBV-genotype was determined by INNOLiPA. RESULTS Among the 556 subjects tested, 60 (10.7%) resulted HBsAg positive. All were men, and 42 (70%) come from Africa, 10 (16.6%) from Asia and 9 (14.4%) from East-Europe. 28/60 (46.6%) patients presented normal ALT levels (<40 IU/L) and undetectable serum HBV DNA (<100 copies/mL in real-time PCR), while 32 (53.4%) patients had ALT levels above laboratory normal values and detectable serum HBV DNA. Genotype distribution was as follow: genotype E, 16 (50%), genotype D, 9 (28.1%), genotype A, 7 (21.9%). CONCLUSION Our study evidences a moderate prevalence of HBV-infection in immigrants, particularly in sub-Saharan African people, and the potentiality of migratory flow in the introduction of genotype non-D hepatitis B virus, potentially characterized by a different natural history and, possibly, a different response to antiviral treatment.

Prevalence of HBV genotypes in South American immigrants affected by HBV-related chronic active hepatitis

This study evaluated the prevalence of HBV infection in a population of South American immigrants in Italy and to determine in patients with detectable serum HBV-DNA the HBV genotypes. Between April 2005 and April 2006 a total of 130 South American immigrants were tested for HBsAg. In HBsAg positive patients the biochemical and virological activity of infection and the possible presence of co-infections (HCV, HDV, HIV) were evaluated. In patients with detectable serum HBV DNA, the HBV genotype was determined by INNOLiPA. Among the 130 subjects tested, 14 (10.7%) resulted HBsAg positive. All were men, with a mean age of 22 years (range 19-37) and 12 (85.7 %) came from Brazil, while 2 (14.3%) came from Ecuador. All patients infected by HBV had elevated alanine-aminotransferase serum levels (mean level was 127 IU/L, range 74-312) and serum HBV DNA detectable by PCR-Real Time (mean level 1,037,652 copies/mL, range 19,876-1,377,648). Genotype distribution was as follow: genotype D, 9 (64.2%), genotype A, 5 (35.8%). All patients infected by genotype D came from Brazil, while among the patients infected by genotype A, three came from Brazil and two from Ecuador. Our study evidences a moderate prevalence of HBV-infection in South American immigrants with the identification of two genotypes, D and A. These genotypes are not the most prevalent in the South America and this is probably the expression of a possible geographical redistribution of HBV genotypes.

Antiretroviral Genotypic Resistance in Plasma RNA and Whole Blood DNA in HIV-1 Infected Patients Failing HAART

The extent to which HIV‐1 proviral DNA mutations cause clinically relevant antiretroviral resistance is still controversial. Paired plasma HIV‐1 RNA and whole blood DNA were compared in patients failing HAART to investigate if the additional knowledge of archived mutations could improve the selection of potentially active drugs. Seventy‐three HIV‐1‐infected patients with first/second HAART failure were studied before starting a new regimen based on RNA genotyping. Follow‐up data after a 12‐week therapy were available. DNA genotyping was retrospectively performed on stored whole blood samples and mutational profiles were compared to those from RNA. The mean number of IAS pol mutations was significantly higher in RNA (4.45 ± 2.76) than in DNA (2.88 ± 2.47) (P < 0.001). DNA genotyping provided a 6% increase in detection of resistance‐associated mutations. Among 64/73 patients showing discordant DNA/RNA profiles, 54 (84%) also differed for predicted active drugs. 16/73 (22%) patients had ≥1 mutation revealed by DNA genotyping alone, probably affecting therapy success in 2/16. However, neither RNA/DNA discordance nor detection of isolated DNA mutations were statistically associated with outcome. In conclusion, plasma RNA remains the elective choice for HIV genotyping in patients with therapy failure, even if the detection of proviral resistance‐associated mutations, not simultaneously found in RNA, is a frequent event. Therefore, in some cases DNA plus RNA genotyping might assist in choosing more accurately subsequent antiretroviral regimens. J. Med. Virol. 80:1695–1706, 2008.

Peginterferon alfa-2b Treatment for Patients Affected by Acute Hepatitis C: Presentation of Six Case Reports

Acute hepatitis C often progresses to chronic infection (70%). In this clinical study, we evaluated if early treatment with peginterferon alfa-2b can prevent acute hepatitis C from developing into a chronic disease. Six patients with acute hepatitis C, based on a well-documented hepatitis C virus (HCV) seroconversion with high alanine aminotransferase (ALT) levels (> 10 x ULN) and persistent HCV RNA titers after 3 months from disease onset, were consecutively treated with peginterferon alfa-2b at 1.5 µg/kg/weekly/sc for 24 weeks. The viral load was quantified by PCR assay. Response was defined as undetectable HCV RNA and normal ALT levels at the end of therapy and after a 6-month follow-up. All patients completed therapy; at the end of therapy, 5/6 patients (83%) responded and no relapses were observed during follow-up. No correlation was found between treatment response and pretreatment viral load, viral genotype, and interval between acute infection diagnosis and start of therapy.

Prolonged lamivudine treatment in patients with chronic active anti-HBe-positive hepatitis.

The efficacy of lamivudine (LAM) at 100 mg/d for 1 year in normalizing serum ALT levels and suppressing HBV DNA has been demonstrated in many studies. However, frequent relapses make long-term results modest. In the present study, we evaluated the efficacy of LAM administered for 3 years in patients with chronic active anti-HBe–positive hepatitis. Thirty-four patients with chronic active anti-HBe–positive hepatitis were treated with LAM (100 mg) once daily for 3 years. Before treatment, all patients demonstrated serum ALT levels >2 times normal levels for >6 months and HBV DNA positivity >5 pg/mL as determined by the sandwich hybridization test for nucleic acid. Both ALT and HBV DNA were monitored during therapy. After 12 months of therapy, 24 of 34 patients (70.6%) showed evidence of HBV DNA clearance and normal ALT levels; 22 of 34 (64.7%) and 19 of 34 (55.8%) patients maintained a complete response after 2 and 3 years of therapy, respectively. The long-term LAM therapy (>1 year) was not associated with an increase in the response of intially nonresponder patients. The YMDD variant emerged in 17.6% of patients in the first year, in 35.2% during the second year, and 52.9% during the third year of treatment. LAM was well tolerated during the 3-year therapy in all patients. Patients with chronic active anti-HBe–positive hepatitis demonstrated that the LAM response rate tends to decrease over time due to the emergence of YMDD variants.

V3 Sequences and Paired HIV Isolates from 52 Non-Subtype B HIV Type 1-Infected Patients

Viral isolation and V3 sequencing were performed for 52 patients with non-subtype B viruses. The HIV-1 isolation rate was 93%, and 98% of isolates were characterized as NSI. V3 sequences corresponding to NSI isolates were compared to non-subtype B sequences with corresponding SI isolates from the Los Alamos database. The two sequence groups significantly differed in number of sequences with 35 amino acids, net charge, Briggs coefficient, loss of NGS at positions 6-8, and 11/25 genotype (p < 0.0001). Substantial discrepancies in V3 variability were also observed. Basic amino acids at positions 8, 21, 23, and 24 were more frequent in SI sequences as were uncharged amino acids at positions 5, 6, 7, 8, 12, 13, 25, and 34. When characterizing paired viral isolates and V3 sequences from patients with non-subtype B HIV-1, current V3 sequence-based criteria from subtype B appeared to discriminate well between NSI and SI sequences from non-subtype B patients.