Hans Norrgren

A Risk for Hepatocellular Carcinoma Persists Long-term After Sustained Virologic Response in Patients With Hepatitis C-Associated Liver Cirrhosis

BACKGROUND The long-term effect of sustained virologic response (SVR) to antiviral therapy on the risk of developing hepatocellular carcinoma (HCC), liver complications, liver-related death, and overall death in hepatitis C virus (HCV)-infected patients with liver cirrhosis is not fully known. METHODS These risks were evaluated during long-term follow-up in 351 patients with HCV-related cirrhosis. One hundred ten patients with SVR, 193 with non-SVR, and 48 who were untreated were included in a multicenter cohort that was initiated in 2001 and prospectively followed up for a mean of 5.3 (SD, 2.8) years. Complementary follow-up data from national registries were used to minimize the loss of patients during follow-up. RESULTS Six patients with SVR developed HCC at 0.04, 0.64, 2.4, 7.4, 7.4, and 7.6 years, respectively, after achieving SVR. The incidences of HCC, any liver complication, liver-related death, and overall death per 100 person-years were significantly lower in SVR time with 1.0, 0.9, 0.7, and 1.9, compared to 2.3, 3.2, 3.0, and 4.1 in non-SVR and 4.0, 4.9, 4.5, and 5.1 in untreated time. The long-term consequences did not decline significantly after >3 years versus during the first 3 years of follow-up. CONCLUSIONS The risk for HCC, liver decompensation, and death in patients with liver cirrhosis related to HCV was markedly reduced after SVR, but a long-term risk of developing HCC remains for up to 8 years. Cirrhotic patients with HCV who achieve SVR should therefore maintain long-term surveillance for HCC. Future studies aimed to better identify those with remaining long-term risk for HCC are needed.

Trends and interaction of Hiv-1 and Hiv-2 in Guinea-bissau, west Africa: no protection of Hiv-2 against Hiv-1 infection

OBJECTIVES To study trends in the prevalence and incidence of HIV-1 and HIV-2 infections in Guinea-Bissau over the last 7 years, and to evaluate the protective effect of HIV-2 against HIV-1 infection. DESIGN Prospective follow-up of a cohort of police officers in Guinea-Bissau, and sentinel surveillance of pregnant women in Bissau. METHODS Participants in the police cohort were tested regularly for antibodies to HIV and Treponema pallidum, and information about sexual risk behaviour and a history of sexually transmitted diseases was obtained. Simultaneously, pregnant women at the maternity wards at the National Hospital in Bissau were screened annually for HIV antibodies. To evaluate changes in prevalence and incidence of HIV in the police cohort, the study period was divided into three time strata with 2-3 years in each stratum. For the evaluation of a protective effect of HIV-2 on subsequent HIV-1 infection, two multivariate Poisson regression models were constructed, adjusting for different selected confounding variables. RESULTS Between 1990 and 1997, 2637 police officers were included in the cohort study, 90.7% of whom were male. The overall prevalence of HIV-1 was 0.9%, of HIV-2 it was 9.7% and of HIV-1 and HIV-2 dual reactivity it was 0.5%. For pregnant women the prevalence rates were 0.9, 5.5 and 0.2% for HIV-1, HIV-2 and dual reactivity respectively. The prevalence of HIV-1 increased significantly whereas the prevalence of HIV-2 declined significantly during the study period, among both police officers and pregnant women. The total incidence of HIV-1 and HIV-2 was 0.74 and 0.83 per 100 person-years respectively in the police cohort. The incidence of HIV-1 increased slightly from 0.62 to 0.78 per 100 person-years (not significant), whereas the incidence of HIV-2 declined significantly from 0.90 to 0.35 per 100 person-years over the study period. Seven police officers seroconverted from HIV-2 to dual reactivity (1.22 per 100 person-years). The adjusted incidence ratio of acquiring HIV-1 infection among HIV-2-positive subjects compared with HIV-negative subjects was 1.65 [95% confidence interval (CI), 0.73-3.74] and 1.98 (95% CI, 0.80-4.87), depending on the confounding variables included. CONCLUSIONS Our study shows an increasing prevalence of HIV-1 and a decreasing prevalence of HIV-2 in Guinea-Bissau. The incidence of HIV-2 declined significantly whereas the incidence of HIV-1 was relatively stable over the study period. No protective effect of HIV-2 against subsequent HIV-1 infection was observed, instead HIV-2-positive subjects had a tendency towards higher risk of acquiring HIV-1 infection compared with seronegative subjects.

Frequent CXCR4 tropism of HIV-1 subtype A and CRF02_AG during late-stage disease - indication of an evolving epidemic in West Africa

BackgroundHIV-1 is one of the fastest evolving pathogens, and is distinguished by geographic and genetic variants that have been classified into different subtypes and circulating recombinant forms (CRFs). Early in infection the primary coreceptor is CCR5, but during disease course CXCR4-using HIV-1 populations may emerge. This has been correlated with accelerated disease progression in HIV-1 subtype B. Basic knowledge of HIV-1 coreceptor tropism is important due to the recent introduction of coreceptor antagonists in antiretroviral therapy, and subtype-specific differences regarding how frequently HIV-1 CXCR4-using populations appear in late-stage disease need to be further investigated. To study how frequently CXCR4-using populations appear in late-stage disease among HIV-1 subtype A and CRF02_AG, we evaluated the accuracy of a recombinant virus phenotypic assay for these subtypes, and used it to determine the HIV-1 coreceptor tropism of plasma samples collected during late-stage disease in Guinea-Bissau. We also performed a genotypic analysis and investigated subtype-specific differences in the appearance of CXCR4 tropism late in disease.ResultsWe found that the recombinant virus phenotypic assay accurately predicted HIV-1 coreceptor tropism of subtype A and CRF02_AG. Over the study period (1997-2007), we found an increasing and generally high frequency of CXCR4 tropism (86%) in CRF02_AG. By sequence analysis of the V3 region of our samples we developed a novel genotypic rule for predicting CXCR4 tropism in CRF02_AG, based on the combined criteria of the total number of charged amino acids and net charge. This rule had higher sensitivity than previously described genotypic rules and may be useful for development of future genotypic tools for this CRF. Finally, we conducted a literature analysis, combining data of 498 individuals in late-stage disease, and found high amounts of CXCR4 tropism for all major HIV-1 subtypes (60-77%), except for subtype C (15%).ConclusionsThe increase in CXCR4 tropism over time suggests an evolving epidemic of CRF02_AG. The results of the literature analysis demonstrate the need for further studies investigating subtype-specific emergence for CXCR4-tropism; this may be particularly important due to the introduction of CCR5-antagonists in HIV treatment regimens.

Inhibition of HIV-1 Disease Progression by Contemporaneous HIV-2 Infection

BACKGROUND Progressive immune dysfunction and the acquired immunodeficiency syndrome (AIDS) develop in most persons with untreated infection with human immunodeficiency virus type 1 (HIV-1) but in only approximately 20 to 30% of persons infected with HIV type 2 (HIV-2); among persons infected with both types, the natural history of disease progression is poorly understood. METHODS We analyzed data from 223 participants who were infected with HIV-1 after enrollment (with either HIV-1 infection alone or HIV-1 and HIV-2 infection) in a cohort with a long follow-up duration (approximately 20 years), according to whether HIV-2 infection occurred first, the time to the development of AIDS (time to AIDS), CD4+ and CD8+ T-cell counts, and measures of viral evolution. RESULTS The median time to AIDS was 104 months (95% confidence interval [CI], 75 to 133) in participants with dual infection and 68 months (95% CI, 60 to 76) in participants infected with HIV-1 only (P=0.003). CD4+ T-cell levels were higher and CD8+ T-cell levels increased at a lower rate among participants with dual infection, reflecting slower disease progression. Participants with dual infection with HIV-2 infection preceding HIV-1 infection had the longest time to AIDS and highest levels of CD4+ T-cell counts. HIV-1 genetic diversity was significantly lower in participants with dual infections than in those with HIV-1 infection alone at similar time points after infection. CONCLUSIONS Our results suggest that HIV-1 disease progression is inhibited by concomitant HIV-2 infection and that dual infection is associated with slower disease progression. The slower rate of disease progression was most evident in participants with dual infection in whom HIV-2 infection preceded HIV-1 infection. These findings could have implications for the development of HIV-1 vaccines and therapeutics. (Funded by the Swedish International Development Cooperation Agency-Swedish Agency for Research Cooperation with Developing Countries and others.).

Intestinal parasites in HIV-2 associated AIDS cases with chronic diarrhoea in Guinea-Bissau.

Previous studies from African countries where HIV-1 infection is prevalent have shown that infections with Cryptosporidium parvum, Isospora belli and microsporidia are frequently associated with chronic diarrhoea in AIDS patients. The information about the occurrence of these parasites in HIV-2 associated AIDS cases with chronic diarrhoea is limited. We have performed a study of stool parasites in patients from Guinea-Bissau, the country with the highest prevalence of HIV-2 in the world. Stool specimens from 52 adult patients with chronic diarrhoea of which 37 were HIV-positive and fulfilling the clinical criteria of AIDS (five HIV-1, 28 HIV-2 and four dually infected with HIV-1 and HIV-2) were screened for parasitic infections. Twenty five percent of the HIV-2 positive patients were infected with C. parvum, 11% with I. belli and 11% with microsporidia, all three parasites were seen only in HIV-positive patients. The three patients with microsporidiosis, all HIV-2 infected, are to our knowledge the first cases reported from Guinea-Bissau. Other stool parasites such as Blastocystis hominis, hookworm and Strongyloides stercoralis were observed both among HIV-positive and HIV-negative patients.

HIV-1 Molecular Epidemiology in Guinea-Bissau, West Africa: Origin, Demography and Migrations

The HIV-1 epidemic in West Africa has been dominated by subtype A and the recombinant form CRF02_AG. Little is known about the origins and the evolutionary history of HIV-1 in this region. We employed Maximum likelihood and Bayesian methods in combination with temporal and spatial information to reconstruct the HIV-1 subtype distribution, demographic history and migration patterns over time in Guinea-Bissau, West Africa. We found that CRF02_AG and subsubtype A3 were the dominant forms of HIV-1 in Guinea-Bissau and that they were introduced into the country on at least six different occasions between 1976 and 1981. These estimates also corresponded well with the first reported HIV-1 cases in Guinea-Bissau. Migration analyses suggested that (1) the HIV-1 epidemic started in the capital Bissau and then dispersed into more rural areas, and (2) the epidemic in Guinea-Bissau was connected to both Cameroon and Mali. This is the first study that describes the HIV-1 molecular epidemiology in a West African country by combining the results of subtype distribution with analyses of epidemic origin and epidemiological linkage between locations. The multiple introductions of HIV-1 into Guinea-Bissau, during a short time-period of five years, coincided with and were likely influenced by the major immigration wave into the country that followed the end of the independence war (1963–1974).

HIV-1, HIV-2, HTLV-I/II and Treponema pallidum infections: incidence, prevalence, and HIV-2-associated mortality in an occupational cohort in Guinea-Bissau.

The prevalence and incidence of human immunodeficiency virus types 1 and 2 (HIV-1, HIV-2), human T-lymphotropic virus types I and II (HTLV-I/II), and syphilitic infections and the association between these infections were determined in a cohort of police officers in Guinea-Bissau. Between January 1990 and December 1992, 1,384 subjects (1,241 men and 143 women) were included in the study; and of the first 879 tested, 561 were tested at least for a second time. The overall seroprevalence of HIV-1 was 0.4%, of HIV-2 11.6%, and of HTLV I/II 4.4%. Three individuals (0.2%) were seropositive for both HIV-1 and HIV-2. Women had a significantly higher prevalence of HIV-2 infection than men (16.8% and 11.0%, respectively, p < 0.05). Serologic evidence of previous syphilis was present in 12.1% and was significantly more common in men (12.7%) than in women (7.0%) (p < 0.05). There was a significant association between the prevalence of HIV-2 and HTLV-I/II infection (p < 0.05). The annual incidence of HIV-1 was 0.7%, of HIV-2 1.6%, of HTLV I/II 0.4%, and of syphilis 1.7%. There was no association between the incidence of the various infections. The death rate (per 100 person-years) was significantly higher among HIV-2-infected individuals (2.7%) than among HIV-negative individuals (0.5%) (relative risk = 5.1; 95% confidence interval, 2.1-12.2; p < 0.001). HIV-related symptoms were more frequent among the HIV-2-positive individuals who died compared with the seronegative individuals who died (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Prevalence and incidence of HIV-1 and HIV-2 before, during and after a civil war in an occupational cohort in Guinea-Bissau, West Africa.

Objectives:To study prevalence and incidence of HIV-1 and HIV-2 between 1990 and 2007 and to examine impact of the civil war in 1998–1999. We also wanted to investigate possible interaction between HIV-1 and HIV-2. Design:Open prospective cohort study of 4592 police officers in Guinea-Bissau, West Africa. Methods:Analysis of HIV-1 and HIV-2 prevalence and incidence divided in 2–3 years time strata. Results:HIV-1 prevalence (including HIV-1/HIV-2 dual reactivity) increased gradually from 0.6 to 3.6% before the war and was 9.5% in the first serosurvey after the war. HIV-1 incidence more than doubled during and shortly after the war, from 0.50 to 1.22 per 100 person-years. Both prevalence and incidence of HIV-1 decreased in the following periods after the war. HIV-2 prevalence decreased from 13.4 to 6.2% during the entire study period and HIV-2 incidence decreased from 1.38 to 0.18 per 100 person-years. Adjusted incidence rate ratios of HIV-1 incidence in HIV-2-positive participants compared with HIV-negative participants ranged from 1.02 to 1.18 (not significant) depending on the confounding variables included. Conclusion:HIV-1 has increased, whereas HIV-2 has decreased and the risk of acquiring HIV-1 is now more than four times higher as compared with HIV-2. The civil war in 1998–1999 appears to have induced a temporary increase in HIV-1 transmission, but now a stabilization of HIV-1 incidence and prevalence seems to have taken place. There was no evidence of a protective effect of HIV-2 against HIV-1 infection.

HIV-2 genetic variation and DNA load in asymptomatic carriers and AIDS cases in Guinea-Bissau.

The purpose of this study was to document which genetic subtypes of HIV-2 are present in Guinea-Bissau and to investigate whether asymptomatic HIV-2 carriers and AIDS patients carry distinct genetic variants. A secondary aim was to correlate proviral DNA load to clinical and immunologic status of the patients. Thirty-eight asymptomatic HIV-2 carriers and 11 AIDS patients from Bissau, Guinea-Bissau were included in a cross-sectional study in which HIV-2 env V3 sequences, HIV-2 DNA load, and CD4-positive (CD4+) lymphocyte counts were determined. Phylogenetic analyses showed that all investigated subjects carried subtype A HIV-2 variants and that the sequences from AIDS patients and asymptomatic carriers did not form distinct subclusters in the tree. As expected, patients with AIDS had significantly higher median HIV-2 DNA load than did asymptomatic carriers (4.6 vs. 2.0 log10 HIV-2 DNA copies/10(6) CD4+ lymphocytes). Our study indicates that the HIV-2 epidemic in Guinea-Bissau is almost exclusively caused by subtype A HIV-2 variants and that the HIV-2 infections among the asymptomatic carriers and AIDS cases included in the study do not have distinct epidemiologic histories.

Potent Intratype Neutralizing Activity Distinguishes Human Immunodeficiency Virus Type 2 (HIV-2) from HIV-1

ABSTRACT HIV-2 has a lower pathogenicity and transmission rate than HIV-1. Neutralizing antibodies could be contributing to these observations. Here we explored side by side the potency and breadth of intratype and intertype neutralizing activity (NAc) in plasma of 20 HIV-1-, 20 HIV-2-, and 11 dually HIV-1/2 (HIV-D)-seropositive individuals from Guinea-Bissau, West Africa. Panels of primary isolates, five HIV-1 and five HIV-2 isolates, were tested in a plaque reduction assay using U87.CD4-CCR5 cells as targets. Intratype NAc in HIV-2 plasma was found to be considerably more potent and also broader than intratype NAc in HIV-1 plasma. This indicates that HIV-2-infected individuals display potent type-specific neutralizing antibodies, whereas such strong type-specific antibodies are absent in HIV-1 infection. Furthermore, the potency of intratype NAc was positively associated with the viral load of HIV-1 but not HIV-2, suggesting that NAc in HIV-1 infection is more antigen stimulation dependent than in HIV-2 infection, where plasma viral loads typically are at least 10-fold lower than in HIV-1 infection. Intertype NAc of both HIV-1 and HIV-2 infections was, instead, of low potency. HIV-D subjects had NAc to HIV-2 with similar high potency as singly HIV-2-infected individuals, whereas neutralization of HIV-1 remained poor, indicating that the difference in NAc between HIV-1 and HIV-2 infections depends on the virus itself. We suggest that immunogenicity and/or antigenicity, meaning the neutralization phenotype, of HIV-2 is distinct from that of HIV-1 and that HIV-2 may display structures that favor triggering of potent neutralizing antibody responses.