Evolution of proviral DNA HIV-1 tropism under selective pressure of maraviroc-based therapy

OBJECTIVES

To evaluate the evolution of HIV-1 coreceptor tropism in proviral DNA of patients during maraviroc-based therapy.

METHODS

Fourteen heavily high active antiretroviral therapy (HAART)-treated patients with a CCR5 Trofile profile were monitored over a 24 month period from the start of maraviroc therapy. Whole-blood samples were obtained at different timepoints, and coreceptor tropism was determined for proviral DNA from the V3-loop region sequence using the Geno2Pheno algorithm [false positive rate (FPR): 20%].

RESULTS

At the start of maraviroc treatment, 13/14 patients were viraemic (median: 4.33 log copies/mL). Concordance in R5 tropism (R5/R5) was observed between circulating HIV-RNA (Trofile) and HIV-DNA provirus in 10/14 patients (median FPR = 54.0%), while 4 patients showed a CXCR4-tropic R5/X4 variant in their provirus (FPR: 5.8%, 5.7%, 16.6% and 1.1%, respectively). All R5/R5 patients showed a stable HIV-1 DNA coreceptor usage. Two out of four R5/X4 patients showed a tropism shift in their archived provirus and, after 6 months a prevalence of R5-tropic virus was detected in DNA. The other two R5/X4 patients harboured the 11/25 genotype, and maintained X4 tropism in provirus during the study. Virological response did not reveal differences in RNA decay and CD4+ cell recovery in patients with discordant tropism.

CONCLUSIONS

A relatively good correlation between RNA and DNA tropism was observed at baseline. Proviral DNA tropism remained stable over 24 months of maraviroc-based therapy, indicating that determination of proviral DNA V3 sequence could be used in tropism prediction in clinical practice. The data also confirm the importance of the 11/25 rule in predicting viral tropism.

Performance of genotypic tropism testing on proviral DNA in clinical practice: results from the DIVA study group

OBJECTIVE

The DIVA study is aimed at setting up a standardized genotypic tropism-testing on proviral-DNA for the routine clinical diagnostic-laboratory.

METHODS

Twelve local centres and 5 reference centres (previously cross-validated) were identified. For inter-center validation-procedure, 60 peripheral-blood mononuclear cells (PBMCs) aliquots from 45 HAART-treated patients were randomly chosen for population V3 sequencing on proviral-DNA at local HIV centre and at reference-laboratory. Viral tropism was predicted by Geno2Pheno algorithm (False Positive Rate [FPR] = 20%) as proposed by the European-Guidelines. Quantification of total HIV-1 DNA was based on a method described by Viard (2004).

RESULTS

Quantification of HIV-1 DNA was available for 35/45 (77.8%) samples, and gave a median value of 598 (IQR:252- 1,203) copies/10 PBMCs. A total of 56/60 (93.3%) samples were successfully amplified by both the reference and the local virological centers. The overall concordance of tropism prediction between local and reference centers was 54/56 (96.4%). Results of tropism prediction by local centers were: 33/54 (61.1%) R5 and 21/54 (38.9%) X4/DM.

CONCLUSION

There was high concordance in the genotypic tropism prediction based on proviral DNA among different virological centers throughout Italy. Our results are in line with other European studies, and support the use of genotypic tropism testing on proviral DNA in patients with suppressed plasma HIV-1 RNA candidate to CCR5-antagonist treatment.

Low rate of virological failure and maintenance of susceptibility to HIV-1 protease inhibitors with first-line lopinavir/ritonavir-based antiretroviral treatment in clinical practice

Protease inhibitor (PI)-resistant HIV-1 has hardly ever been detected at failed boosted PI-based first-line antiretroviral regimens in clinical trials. However, this phenomenon has not been investigated in clinical practice. To address this gap, data from patients starting a first-line lopinavir/ritonavir (LPV/rtv)-based therapy with available baseline HIV-1 RNA load, a viral genotype and follow-up viral load after 3 and 6 months of treatment were extracted from the Italian Antiretroviral Resistance Cohort Analysis (ARCA) observational database. Based on survival analysis, 39 (7.1%) and 43 (7.8%) of the 548 examined patient cases had an HIV-1 RNA >500 and >50 copies/ml, respectively, after 6 months of treatment. Cox proportional hazard models detected baseline HIV-1 RNA (RH 1.79, 95%CI 1.10-2.92 per 1-log(10) increase, P=0.02) and resistance to the nucleoside backbone (RH 1.04, 95%CI 1.02-1.06 per 10-point increase using the Stanford HIVdb algorithm, P<0.001) as independent predictors of HIV-1 RNA at >500 copies/ml, but not at the >50 copies/ml cutoff criteria. Higher baseline viral load, older patient age, heterosexual route of infection and use of tenofovir/emtricitabine were predictors of failure at month 3 using the 50-copy and/or 500-copy threshold. Resistance to LPV/rtv did not occur or increase in any of the available 36 follow-up HIV-1 genotypes. Resistance to the nucleoside backbone (M184V) developed in four cases. Despite the likely differences in patient population and adherence, both the low rate of virological failure and the lack of development of LPV/rtv resistance documented in clinical trials are thus confirmed in clinical practice.

Performance of genotypic tropism testing in clinical practice using the enhanced sensitivity version of Trofile as reference assay: results from the OSCAR Study Group

OBJECTIVE

The goal of the OSCAR programme is to evaluate the performances of genotypic HIV-1 tropism testing in clinical practice using the enhanced sensitivity version of Trofile (ESTA) as reference-assay.

METHODS

HIV-1 coreceptor-usage was assessed using plasma samples from 406 HIV-1 infected patients by ESTA and by gp120 V3 population-sequencing followed by Geno2pheno (set at a False Positive Rate [FPR] of 10% and 5%).

RESULTS

ESTA was successful in 365 (89.9%) samples indicating R5 in 254 (69.6%), and DM/X4 in 111 (30.4% of samples (104 [28.5%] DM and 7 [1.9%] X4). Genotypic-testing successfully assessed viral tropism for all 406 samples, including the 41 with undetermined result by ESTA. Genotypic-tropism testing at a FPR of 5% and 10% was 81.1% and 78.4% concordant with ESTA, respectively. Despite a sensitivity of 48.7% and 55.9% at a FPR of 5% and 10%, respectively, a high concordance (specificity: 95.3% for FPR of 5% and 88.2% for FPR of 10%) between genotypic-tropism testing and ESTA was reached in the detection of R5-tropic viruses.

CONCLUSION

Our results are in line with other European studies, and support the routine use of genotypic tropism testing in clinical-settings for monitoring of HIV-1 infected patients candidate to or failing CCR5-antagonists.

Prevalence of mutations and determinants of genotypic resistance to etravirine (TMC125) in a large Italian resistance database (ARCA)

OBJECTIVES

To evaluate whether etravirine (TMC125) might be effective in patients failing therapy with current nonnucleoside reverse transcriptase inhibitors (NNRTIs), we analysed the prevalence of TMC125 mutations and the possible determinants of genotypic resistance to this drug among sequences reported to a large database in Italy [Antiretroviral Resistance Cohort Analysis (ARCA)].

METHODS

We analysed the prevalence of TMC125 resistance-associated mutations (RAMs) and the TMC125 weighted genotypic score (WGS) together with the determinants of genotypic resistance. A total of 5011 sequences from 2955 patients failing NNRTI therapy were evaluated.

RESULTS

Among the sequences in ARCA, 68% had at least one and 9.8% at least three TMC125 RAMs, whereas 31% had a WGS>2. Frequent RAMs were Y181C, G190A, K101E and A98G, whereas V179F, Y181V and G190S appeared in <5% of sequences. Multivariate analysis revealed a higher risk of developing at least three TMC125 RAMs associated with both nevirapine and efavirenz exposure, whereas CD4 counts > or = 200 cells/microL retained their protective effect. An increased risk of WGS>2 was linked to higher HIV RNA values (maximum risk at >5 log(10) copies/mL) and nevirapine exposure; CD4 counts > or = 200 cells/microL were protective.

CONCLUSIONS

The prevalence of TMC125 resistance mutations in the ARCA cohort was 68%. The DUET studies showed that at least three TMC125-associated mutations were required to impair the efficacy of the drug and Y181C/V, V179F and G190S had the greatest effect on response. The prevalence of these mutations among the patients examined in our study was low. However, WGS>2 was found for one-third of our sequences. Previous nevirapine exposure was associated with an increased risk of having WGS>2 (adjusted odds ratio 1.76).

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, Brigg's 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.

QuantiFERON-TB Gold In-Tube test (QFT-GIT) for the screening of latent tuberculosis in recent immigrants to Italy

To evaluate the agreement between QuantiFERON-TB Gold In-Tube test (QFT-GIT) and tuberculin skin test (TST) for the screening of latent tuberculosis infection (LTBI) in recent immigrants to Italy, 279 subjects were submitted to concomitant TST and QFT-GIT. The agreement was analyzed using k statistics. A total of 72/279 (25.8%) individuals were TST positive, while 107/279 (38.3%) were QFT-GIT positive. The overall agreement between QFT-GIT and TST was 70.9%, with k statistic of 0.35. Using different TST and QFT-GIT cut-offs, the best concordance value was obtained for QFT-GIT at > 2.64 IU/ml and TST at > 10mm (k = 0.409). Discordant results were found for 58 subjects (21%) with QFT-GIT positive/TST negative and 23 (8%) with QFT-GIT negative/TST positive. A high amount of discordance QFT-GIT+/TST- was described. QFT-GIT might increase the identification of LTBI cases among recent immigrants.

Clinical validation and applicability of different tipranavir/ritonavir genotypic scores in HIV-1 protease inhibitor-experienced patients

Tipranavir, a non-peptidic protease inhibitor which shows in vitro efficacy against some HIV-1-resistant strains, can be used in salvage therapies for multi-experienced HIV patients due to its peculiar resistance profile including 21 mutations at 16 protease positions according to International AIDS Society (IAS). Other genotypic scores, however, which attribute a different weight to single amino-acid substitutions, have been recently proposed. To validate the clinical utility of four different genotypic scores for selecting tipranavir responders, the baseline resistance pattern of 176 HIV heavily experienced patients was correlated with virological success (HIV-RNA<50 copies/ml) after 24 weeks of a new treatment based on tipranavir/ritonavir. Virological suppression after 24 weeks was reached by 42.5% of patients. With univariate analysis, genotypic scores were all associated with outcome but showed a low accuracy with ROC analysis, with the weighted score (WS) by Scherer et al. demonstrating the best performance with an AUC of 68%. Only 52% of patients classified as susceptible (WS< or =3) responded to the new therapy. The following variables were significantly associated (p<0.05) to failure with multivariate analysis: WS, log peak of HIV-RNA, IAS mutations: L33F, I54AMV, Q58E, and non-IAS mutation: N37DES. On the contrary, the use of T20 in T20-naïve patients and the V82AFSI and F53LY non-IAS mutations were associated with virological success. The study suggests that even if the "weighted" scores are able to interpret correctly the antiretroviral resistance profile of multi-experienced patients, it is difficult to individuate a cut-off which can be easily applied to this population for discriminating responders.

Long-Term Efficacy and Safety of TDM-Assisted Combination of Voriconazole plus Efavirenz in an AIDS Patient with Cryptococcosis and Liver Cirrhosis

Objective

To report the efficacy, tolerability, and pharmacokinetic effects of combined voriconazole and efavirenz treatment administered at therapeutic drug monitoring (TDM)–based adjusted doses to a patient with AIDS, cryptococcosis, and mild liver cirrhosis.

Case Summary

A 40-year-old man with AIDS (hemophiliac, antiretroviral-naïve, plasma HIV-RNA = 290,000 copies/mL, CD4+ lymphocytes = 0), hepatitis C virus–related liver cirrhosis (Child-Pugh class A), and cryptococcal meningitis was failing standard antifungal therapies. He received an antifungal–antiretroviral combination treatment based on the association of voriconazole plus efavirenz. Doses of both drugs were serially adjusted based on their plasma concentrations, which were evaluated at steady-state of each dose combination at least once (week 3.1 or later) as full concentration–time profile (samples collected at 0, 1, 2, 3, 4, 6, 8, 12 h postdose). Adequate concentrations of voriconazole in both plasma and cerebrospinal fluid were obtained and target plasma concentrations of efavirenz were achieved at the final dose adjustment (voriconazole 200 mg twice daily plus efavirenz 300 mg once daily, both administered orally). The patient showed prompt and stable suppression of cryptococcosis and plasma viremia of HIV at long-term follow-up (66 wk), with no significant adverse events.

Discussion

Standard therapies for cryptococcosis in patients with AIDS are often not effective. Voriconazole, despite its promising anticryptococcal efficacy, is currently not approved for cryptococcosis therapy in the US and Europe, nor is it recommended for combination with efavirenz due to the significant pharmacokinetic interactions between the 2 compounds. Thus far, published studies regarding the effects of voriconazole in human cryptococcosis are scarce and none has described the clinical and pharmacokinetic outcomes of a voriconazole/efavirenz combination in patients with AIDS, either with or without liver cirrhosis.

Conlusions

The combination of voriconazole and efavirenz at TDM-assisted doses may represent a valuable therapeutic option in AIDS patients with cryptococcosis and mild liver cirrhosis.

Genotypic analysis of the protease and reverse transcriptase of non-B HIV type 1 clinical isolates from naïve and treated subjects

One hundred and ninety-two pol sequences of drug-naïve and drug-experienced subjects infected with non-B HIV-1 subtypes were analyzed to identify treatment-related amino acid changes which might be relevant for drug-resistance and possibly not included in the accepted mutation list for the B subtype. The correspondence analysis identified non-B-specific and subtype-specific polymorphisms which should not be mistaken for mutations. Multiple chi(2) were performed to detect the differences between naïve vs treated subjects and between different subtypes. To verify the contribution of each single mutation to the resistance levels as predicted by the Virtual Phenotype-LM, simple univariate linear regression was used with fold resistance as a dependent variable and individual mutations as predictors. Commonly accepted protease (PR) and reverse transcriptase (RT) positions along with mutants at RT positions 118 and 90 were significantly associated with treatment. Two unusual PR (K14R and I66F) and five RT positions (E28K, S68G, H221Y, L228R/H and P294A) were also associated with treatment (p<0.01). Only minimal variations were observed with respect to commonly accepted amino acid changes. All amino acid changes correlated with treatment influenced the resistance levels to each single drug. Our findings demonstrate that there are no substantial differences regarding known resistance-associated mutations and the newly emergent substitutions between non-B and B subtype strains.

Aeromonas sobria sepsis complicated by rhabdomyolysis in an HIV-positive patient: case report and evaluation of traits associated with bacterial virulence

Human infection with Aeromonas species is uncommon and most often due to trauma with exposure to contaminated water or soil. A 43-year-old HIV- and hepatitis C virus (HCV)-infected male, after a two-week course of corticosteroid therapy for an autoimmune anemia, developed diarrhea, dermatologic manifestations and a multiple organ dysfunction syndrome, resulting in death. Although stool samples were repeatedly negative, two sets of blood cultures obtained during a single peak of fever yielded the post-mortem isolation of a Gram-negative, oxidase-positive, beta-hemolytic bacillus that was identified as Aeromonas sobria. Empiric antibiotic therapy was unsuccessful. Evaluation of the virulence-associated traits of the clinical isolate (adhesion, cytotoxicity activity, biofilm production) showed that the strain was a poor producer of recognized virulence factors, thereby indicating that the unfortunate coexistence of HIV infection, HCV-related liver cirrhosis and corticosteroids played a key role in the clinical course.

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 >or=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.

The correct approach to community-acquired pneumonia in immunocompetent adults: review of current guidelines

Community-acquired pneumonia (CAP) often represents a clinical emergency requiring prompt and adequate antimicrobial treatment. The choice of antimicrobials, however, is difficult due to the variety of potential pathogens and to the spread of drug-resistance. Hence, a correct therapeutic approach should be based on the knowledge of the most frequently reported etiologies for the different clinical conditions, specific patient risk factors and the treatment setting (home, hospital, intensive or non intensive care unit) chosen accordingly. The awareness of the local drug-resistance epidemiology and individual patient characteristics, such as age, history of antibiotic treatments and related adverse events, underlying diseases, concurrent therapies and expected adherence to treatment should also be considered. Lastly, an adequate CAP management should address other issues, including therapy duration, monitoring of its efficacy and adverse effects, and supportive measures. The guidelines for CAP management aim to provide the physician with the necessary knowledge and criteria to assist him in these crucial decisions, and their adoption result in a significant reduction of mortality, frequency and length of hospitalization, and costs. Herein, the authors review and discuss some of the main current guidelines for CAP management, highlighting their differences and similarities.

HIV-1 biological phenotype and predicted coreceptor usage based on V3 loop sequence in paired PBMC and plasma samples

Paired PBMCs and plasma samples from 34 HIV-infected patients were studied to verify the relationship between coreceptor use based on genotyping of V3 region of HIV-1 envelope gp120 and biological phenotype with virus isolation and subsequent correlation to clinical characteristics. The "11/25" rule, geno2pheno and PSSM were compared. All SI patients were HIV-1 subtype B (p=0.04) and had a lower CD4 count than NSI patients (p=0.01), while no differences were observed in mean HIV-RNA (log) (p=0.6). SI phenotype was not associated with AIDS-defining events (p=0.1) or with concurrent antiretroviral therapy (p=0.4). With geno2pheno, which shows the highest sensibility (83%), an X4 or X4/R5 genotype in PBMC DNA was also associated to B-subtype and lower CD4 count (p=0.01) compared to R5 isolates. Based on plasma RNA sequences, the predicted coreceptor usage agreed with PBMC DNA in 79% of cases with the "11/25" rule, 82% with geno2pheno, and 82% with PSSM. A X4 virus in plasma (but not in PBMCs) was significantly associated with HAART in all three methods (p=0.01 for "11/25" rule, p=0.01 for geno2pheno and p=0.03 for PSSM). Due to viral mixtures and/or difficulties in genotype interpretation, current V3 sequence-based methods cannot accurately predict HIV-1 coreceptor use.

A multidrug-resistant (MDR) HIV type 1 infection in a homosexual man and identified source patient

We report a case (IC) of multidrug-resistant (MDR) HIV-1 infection in which the identification of the source patient (S) was supported by phylogenetic analysis of the pol gene and by the similarity of env sequences. HIV isolates from IC and S were characterized as non-syncytium viruses: a X4 variant (R(11) E(26)) was identified in both cases according to the V3 loop sequence. The pol mutational profile of IC included multiple protease and reverse-transcriptase inhibitor mutations similar to those in S. The lamivudine/tenofovir/tipranavir/ritonavir/enfuvirtide association was effective for IC but not for S.

Difficulties in classifying a/g recombinants: methodological problems or genetic variability?

Thirty pol gene plasma-derived sequences clustering with the circulating recombinant form (CRF) 02_AG (IbNG) (bootstrap 100%) were evaluated to analyze the genomic composition. Subtype assignment was also phylogenetically confirmed by C2-V3 region analysis for 18/21 sequences evaluated. Thereafter, we compared the genomic recombination of the CRF02_AG/IbNG prototype as predicted by bootscanning and Jumping HMMER software (jpHMM) to that of our strains. With these methods, 27% and 50%, respectively, of our clinical sequences demonstrated the same pol structure as the prototype CRF02_A/G-IbNG. However, in subtrees built for each segment predicted by jpHMM (with a bootstrap value of more than 75%), all fragments clustered with IbNG and were distinct from A and G clades. Overall, our sequences resulted in true members of CRF02_AG-IbNG, which, however, appeared to be a subtype phylogenetically separate from A or G, at least with regard to the pol gene.

Amoebic hepatic abscesses in an HIV-positive patient

Herein we report the case of hepatic amoebic abscesses in an HIV-positive Italian seaman with a history of promiscuous heterosexual intercourse. In October 2004, the patient was hospitalized because of fever and recurring abdominal pain. Abdominal ultrasonography revealed six hepatic hypoechoid oval lesions with hyperechoid margins. Stool samples were negative for parasites and bacteria, and serology for Entamoeba histolytica was also negative. Therapy with meropenem plus levofloxacin was initiated. After a partial resolution of clinical symptoms and reduction of three hepatic lesions, the patient was again hospitalized in December 2004, because of recurring intense pain at the right hypochondrium and fever. At this time, one hepatic lesion at the sixth segment was enlarged, two lesions were unchanged, and the remaining three smaller abscesses were resolved. Serum antibodies for E. histolytica and amoebic antigens on the largest abscess drainage were positive; moreover, E. histolytica was also identified on drainage fluid with polymerase chain reaction (PCR). Therapy with metronidazole followed by paromomycin improved both symptoms and radiographic images. This case report suggests that in HIV-infected patients, invasive amoebiasis should be considered and atypical aspects, such as multiple hepatic lesions, delayed positivity of serology for E. histolytica, and possible bacterial superinfection should be evaluated.

Impact of unreported HIV-1 reverse transcriptase mutations on phenotypic resistance to nucleoside and non-nucleoside inhibitors

An extended spectrum of HIV-1 reverse-transcriptase (RT) mutations in HAART-treated patients has been recently described. To verify the possible association of previously unreported RT mutations with a decrease of phenotypic susceptibility to nucleoside (NRTIs) and non-nucleoside (NNRTIs) RT inhibitors, the RT sequence of 328 HIV-1-positive patients (102 naïve and 226 treated with HAART participating in either the PhenGen or Genpherex study) was analyzed. All treated patients were tested at the time of therapeutic failure with both phenotypic (Antivirogram, Virco) and genotypic analyses (VircoGen); the frequency of RT substitutions (positions 1-240) with respect to consensus B was compared to that of naïve patients using a Chi-square test. Amino acid changes at 13 positions not included in the IAS list of resistance-associated mutations were detected more frequently in treated than in naïve subjects. The mutations involving 10 of these positions were associated with a reduced susceptibility to antiretroviral drugs; K20R, T39A, K43EQN, E203KD, H208Y, and D218E were correlated with NRTI resistance while mutations K101EQP, H221Y, K223EQ, L228HR were associated to NNRTI resistance. A correlation was found between K20R and lamivudine resistance (P = 0.006) while T39A (P = 0.005), K43EQN (<0.001), E203KD (P = 0.010), and H208Y (P = < 0.001) seemed to be associated with a previous use of zidovudine and stavudine and with the development of thymidine analog resistance. For H208Y, an association with use/resistance to abacavir (P = 0.004) was also noted. D218E showed a weak association to didanosine resistance (P = 0.013). The data confirm that previously unreported mutations are associated with antiretroviral drug experience and, more importantly, with a reduced susceptibility to NRTIs and NNRTIs.

Cryoglobulinemia in subjects with HCV infection alone, HIV infection and HCV/HIV coinfection

OBJECTIVES

To assess the prevalence of cryoglobulinemia in three groups of patients: HCV-positive/HIV-negative, HCV/HIV co-infected and HIV mono-infected.

METHODS

From September 2002 to December 2003, 58 patients with documented HCV infection, 70 subjects with HIV/HCV co-infection, and 48 subjects with HIV infection alone were enrolled. Serum samples were tested for detectable cryoglobulins, liver enzymes, HCV viral load and HCV genotypes. Plasma HIV-RNA levels and CD4+ cell count were also evaluated in HIV-positive subjects.

RESULTS

Cryoglobulinemia was detected in 24.1% HCV mono-infected, 14.2% HCV/HIV co-infected and 6% HIV mono-infected patients. A significant statistical correlation was found between the presence of cryoglobulins and HCV infection (P = 0.03), while cryoglobulins were unrelated to HIV mono-infection (P = 0.16) and HCV/HIV co-infection (P=0.7). No significant correlation was observed between the presence of cryoglobulinemia and alanine transaminase (ALT) levels, HCV viremia and duration of HCV infection. Circulating cryoglobulins in HIV patients were not correlated with plasma HIV viral load, CD4+ cell count or duration of HIV infection. Only two HCV mono-infected patients complained of arthralgia.

CONCLUSION

A similar rate of cryoglobulinemia prevalence was detected in the patient groups with an HCV-related infection. HIV infection does not appear to play a significant role in cryoglobulin production.

HIV-1 subtypes and circulating recombinant forms (CRFs) from HIV-infected patients residing in two regions of central and southern Italy

A total of 347 pol gene sequences from 88 Tuscan and 259 Apulian subjects (including 52 non-Italians and 9 children) were analyzed phylogenetically. Forty-four (12.6%) non-B subtypes were found, including 3.4% C, 1.4% F1, 0.8% G, and 0.3% each for J and A pure subtypes, and 3.7% CRF02_AG, 1.4% CRF01_AE, 0.6% BF, and 0.3% CRF06-cpx recombinant forms. An additional sample close-matched the pol gene of an unique recombinant form (URF AGK 99GR303). The non-B subtypes were from 40 adults and 4 children; 12 of these 44 patients were epidemiologically linked. Thirty-three of the 44 non-B viruses pertained to non-Italian immigrants and 11 to Italians, signifying that 63.4% immigrants and 3.7% Italians harbored non-B subtypes. The overall frequency of non-B subtypes was higher in Tuscany than in Apulia (18.1% vs. 10.8%). Moreover, 6.1% and 3.0% non-B subtypes were found among Italians from Florence and Apulia, respectively, while 52.1% and 72.4% of immigrants living in Tuscany and Apulia harbored non-B subtypes. Women infected by means of sexual contact prevailed among non-Italian adults; the majority of Italians were males and admitted high-risk sexual behavior. Four Italians had a history of extensive travel in countries of high endemicity. Social and epidemiological changes are responsible for an increasing circulation of non-B subtypes in Italy. Although non-B subtypes principally infect non-Italian patients, in Italy they can no longer be considered exclusively restricted to subjects from endemic areas.