Prevention of HIV-associated opportunistic infections and diseases in the age of highly active antiretroviral therapy

Epidemiology of malaria among HIV/AIDS patients in sub-Saharan Africa: A systematic review and meta-analysis of observational studies

Malaria related HIV morbidity and death is a concern in sub-Saharan Africa. Understanding the epidemiology of malaria among people living with HIV is vital for adequate intervention. We conducted a systematic review and meta-analysis to estimate the prevalence of malaria in HIV patients in sub-Saharan Africa. We searched PubMed, AJOL, Web of Science and Google Scholar databases. The overall pooled prevalence and pooled Odds Ratio (OR) with their 95% Confidence Intervals (CI) were estimated using the random-effects model and potential causes of heterogeneity in prevalence estimates were investigated using subgroup and meta-regression analysis. 58 studies, including 23,911 HIV patients, were identified between January 1990 and October 2020. The overall pooled prevalence of malaria in HIV patients was 22.7% (95% CI 18.0; 28.1). The Prevalence of malaria among HIV/AIDS patients was 33.1%, 30.2%, 15.3%, and 12.6% in Southern, Western, Central, and Eastern regions of SSA respectively. Prevalence of malaria in the central and western was higher [26.7% (95% CI 20.6; 33.9)] than 13.6% reported in the southern and eastern regions (95% CI 8.8; 20.5). There was a significant decrease in malaria prevalence among HIV/AIDS patients in the Eastern and Southern SSA regions from 21.9% (95% CI 15.5; 30.0) in the 2000-2010 period to 9.7% (95% CI 5.5-16.4) in the post-2010 period compared to the central and western regions. HIV infected patients with low CD4 + T cell count (CD4 < 200 cells/mm3) were 2.19 times more likely to become infected with malaria than those with high CD4 + T cell count (CD4 ≥ 200 cells/mm3) (pooled odds ratio (POR): 2.19 (95%CI 1.20;3.98), while patients on antiretroviral therapy (POR): 0.37 (0.23; 0.59), and in WHO clinical stages I and II (POR): 0.64 (0.28; 1.46), had a lower odds of been infected with malaria. Our review suggests that due consideration should be given to malaria among HIV/AIDS patients in SSA. In particular, the assessment and improvement of preventive measures for malaria/HIV co-infection in high-prevalence regions is important. For the treatment of both diseases, prophylaxis with cotrimoxazole and antiretroviral therapy should also be encouraged.

Enterocytozoon bieneusi of animals-With an 'Australian twist'

Enterocytozoon bieneusi is a microsporidian microorganism that causes intestinal disease in animals including humans. E. bieneusi is an obligate intracellular pathogen, typically causing severe or chronic diarrhoea, malabsorption and/or wasting. Currently, E. bieneusi is recognised as a fungus, although its exact classification remains contentious. The transmission of E. bieneusi can occur from person to person and/or animals to people. Transmission is usually via the faecal-oral route through E. bieneusi spore-contaminated water, environment or food, or direct contact with infected individuals. Enterocytozoon bieneusi genotypes are usually identified and classified by PCR-based sequencing of the internal transcribed spacer region (ITS) of nuclear ribosomal DNA. To date, ~600 distinct genotypes of E. bieneusi have been recorded in ~170 species of animals, including various orders of mammals and reptiles as well as insects in >40 countries. Moreover, E. bieneusi has also been found in recreational water, irrigation water, and treated raw- and waste-waters. Although many studies have been conducted on the epidemiology of E. bieneusi, prevalence surveys of animals and humans are scant in some countries, such as Australia, and transmission routes of individual genotypes and related risk factors are poorly understood. This article/chapter reviews aspects of the taxonomy, biology and epidemiology of E. bieneusi; the diagnosis, treatment and prevention of microsporidiosis; critically appraises the naming system for E. bieneusi genotypes as well as the phylogenetic relationships of these genotypes; provides new insights into the prevalence and genetic composition of E. bieneusi populations in animals in parts of Australia using molecular epidemiological tools; and proposes some areas for future research in the E. bieneusi/microsporidiosis field.

Long-Term Trends in Esophageal Candidiasis Prevalence and Associated Risk Factors with or without HIV Infection: Lessons from an Endoscopic Study of 80,219 Patients

Background

The prevalence of candida esophagitis (CE) might be changing in an era of highly active antiretroviral therapy (HAART) among HIV-infected patients or today’s rapidly aging society among non-HIV-infected patients. However, few studies have investigated long-term CE trends, and CE risk factors have not been studied in a large sample, case-control study. This study aimed to determine long-term trends in CE prevalence and associated risk factors for patients with or without HIV infection.

Methods

Trends in CE prevalence were explored in a cohort of 80,219 patients who underwent endoscopy between 2002 and 2014. Risks for CE were examined among a subcohort of 6,011 patients. In risk analysis, we assessed lifestyles, infections, co-morbidities, immunosuppressants, and proton-pump inhibitors (PPIs). All patients were tested for HIV, hepatitis B or C virus, and syphilis infection. For HIV-infected patients, sexual behavior, CD4 cell count, history of HAART were also assessed.

Results

CE prevalence was 1.7% (1,375/80,219) in all patients, 9.8% (156/1,595) in HIV-infected patients, and 1.6% (1,219/78,624) in non-HIV-infected patients. CE prevalence from 2002-2003 to 2012-2014 tended to increase in non-HIV-infected patients (0.6% to 2.5%; P<0.01) and decrease in HIV-infected patients (13.6% to 9.0%; P=0.097). Multivariate analysis revealed increasing age (odds ratio [OR], 1.02; p=0.007), HIV infection (OR, 4.92; p<0.001), and corticosteroid use (OR, 5.90; p<0.001) were significantly associated with CE, and smoking (OR, 1.32; p=0.085) and acetaminophen use (OR, 1.70; p=0.097) were marginally associated. No significant association was found with alcohol consumption, hepatitis B or C virus, syphilis, diabetes mellitus, cardiovascular disease, cerebrovascular disease, chronic kidney disease, liver cirrhosis, anticancer, or PPIs use. In HIV-infected patients, CD4 cell count <100/μL (OR, 4.83; p<0.001) and prior HAART (OR, 0.35; p=0.006) were independently associated with CE, but sexual behavior was not. Among corticosteroid users, CE was significantly associated with higher prednisone-equivalent dose (p=0.043 for trend test).

Conclusions

This large, endoscopy-based study demonstrated that CE prevalence increased in non-HIV-infected patients but decreased in HIV-infected patients over 13 years. Risk analysis revealed that increasing age, HIV infection, and corticosteroids use, particularly at higher doses, were independently associated with CE, but alcohol, other infections, diabetes, anticancer drugs, and PPIs use were not.

Dynamics of T-cell subsets and their relationship with oral and systemic opportunistic infections in HIV/AIDS patients during the first year of HAART in Guangxi, China

To analyze the dynamic changes in Th1, Th2, Tc1, and Tc2 of HIV/AIDS patients during the first year of highly active antiretroviral therapy (HAART) and to explore their relationship with oral and systemic opportunistic infections, a cohort study was carried out among HIV/AIDS patients in Guangxi, China. Ninety HIV/AIDS patients and 30 healthy controls (HC) were included. The enrolled HIV/AIDS patients were examined at baseline and after 3, 6, and 12 months of HAART. On each visit, oral and systemic opportunistic infections were recorded, oral Candida load and plasma viral load (VL) were counted, differential T-cell counts and flow cytometric analysis of T-cell subsets were performed. During the first year of HAART, the total number of opportunistic infections decreased steadily with the change in oral candidiasis (OC) most representatively. A significant Th1→Th2 switch (Th1/Th2 ratio 0.23 ± 0.12, HC 1.45 ± 0.38) and slight Tc1→Tc2 shift (Tc1/Tc2 ratio 0.93 ± 0.29, HC 1.13 ± 0.33) were found at baseline, and both received slow mitigation after HAART. LgCFU and clinical OC were correlated positively with both LgVL and clinical stage (P < 0.05) at baseline. LgCFU was also correlated positively with clinical stage at all four time points (P < 0.05). In multiple factor analysis, Th1 was confirmed to be correlated negatively with LgVL (Std.B = -0.295, P = 0.025) and LgCFU (Std.B = -0.227, P < 0.001) at baseline. After HAART, LgCFU and clinical stage were only correlated negatively with CD4 when all factors were included. These results suggest that oral candidiasis and oral Candida load could be useful clinical markers in the evaluation of HIV/AIDS patients. Th1 may play an important role against oral and systemic opportunistic infections. Tc1 and Tc2 both showed positive roles in the control of viremia without HAART. J. Med. Virol. 87:1158-1167, 2015. © 2015 Wiley Periodicals, Inc.

Risk factors for intestinal parasitosis among antiretroviral-treated HIV/AIDS patients in Ethiopia

Summary A cross-sectional survey was conducted to determine the risk factors associated with intestinal parasitosis in HIV/AIDS patients receiving antiretroviral therapy (ART). Socio-demographic information was collected and faecal samples were analysed from 384 randomly selected patients on ART. Data on CD4+ T-cell counts and World Health Organization clinical staging were obtained from the medical records at the hospital. The overall prevalence of intestinal parasitosis was 56% (95% confidence interval [CI]: 51% to 61%). No opportunistic intestinal parasites or Schistosoma haematobium eggs were detected. Unavailability of latrine and lack of hand washing with soap were associated with Entamoeba histolytica/dispar (adjusted odds ratio [AOR], 2.75; 95% CI: 1.77 to 4.27 and AOR, 2.67; 95% CI: 1.60 to 4.44, respectively) and Giardia lamblia (AOR, 2.08; 95% CI: 1.08 to 3.99 and AOR, 2.46; 95% CI: 1.06 to 5.75, respectively) infections. Intestinal parasitosis was significantly associated with low CD4 cell count (p = 0.002). In contrast, intestinal parasitic infections were not associated (p > 0.05) with the World Health Organization disease staging. In summary, poor personal hygiene and sanitation practice contributed to the high prevalence of intestinal parasitosis. Routine diagnosis for intestinal parasitic infections should be performed in patients attending ART clinics in this setting.

Design, synthesis, and molecular modeling of novel pyrido[2,3-d]pyrimidine analogues as antifolates; application of Buchwald-Hartwig aminations of heterocycles

Opportunistic infections caused by Pneumocystis jirovecii (P. jirovecii, pj), Toxoplasma gondii (T. gondii, tg), and Mycobacterium avium (M. avium, ma) are the principal causes of morbidity and mortality in patients with acquired immunodeficiency syndrome (AIDS). The absence of any animal models for human Pneumocystis jirovecii pneumonia and the lack of crystal structures of pjDHFR and tgDHFR make the design of inhibitors challenging. A novel series of pyrido[2,3-d]pyrimidines as selective and potent DHFR inhibitors against these opportunistic infections are presented. Buchwald-Hartwig coupling reaction of substituted anilines with pivaloyl protected 2,4-diamino-6-bromo-pyrido[2,3-d]pyrimidine was successfully explored to synthesize these analogues. Compound 26 was the most selective inhibitor with excellent potency against pjDHFR. Molecular modeling studies with a pjDHFR homology model explained the potency and selectivity of 26. Structural data are also reported for 26 with pcDHFR and 16 and 22 with variants of pcDHFR.

Unusual Enterocytozoon bieneusi genotypes and Cryptosporidium hominis subtypes in HIV-infected patients on highly active antiretroviral therapy

Human immunodeficiency virus (HIV)-infected persons are commonly infected with Cryptosporidium species and Enterocytozoon bieneusi in both developed and developing countries, particularly patients with CD4+ cell counts below 200 cells/μL; 285 HIV-infected patients on highly active antiretroviral therapy (HAART) were enrolled in this study, and both stool and blood specimens were collected from participants. The stool specimens were analyzed and typed for E. bieneusi and Cryptosporidium spp. by polymerase chain reaction (PCR) and DNA sequencing. CD4 count was analyzed using flow cytometry. E. bieneusi and Cryptosporidium were detected in 18 (6.3%) and 4 (1.4%) patients, respectively. The E. bieneusi detected mostly belonged to a new genotype group that, thus far, has only been found in a few humans: genotype Nig4 in 2 patients and two new genotypes related to Nig4 in 12 patients. The Cryptosporidium detected included C. hominis (two patients), C. parvum (one patient), and C. felis (one patient), with the two C. hominis infections belonging to an unusual subtype family. Additional studies are required to determine whether some E. bieneusi genotypes and C. hominis subtypes are more prevalent in HIV patients on HAART.

Prevalence of intestinal parasites and associated risk factors among HIV/AIDS patients with pre-ART and on-ART attending dessie hospital ART clinic, Northeast Ethiopia

Background

Intestinal parasites are a major concern in most developing countries where HIV/AIDS case are concentrate and almost 80% of AIDS patients die of AIDS-related infections. In the absence of ART, HIV/AIDS patients in developing countries unfortunately continue to suffer from the consequences of opportunistic parasites. But this prevalence has dramatically decreased in countries where antiretroviral agents are widely available. Therefore, the aim of this study was to assess the prevalence of intestinal parasite and risk factor among pre- ART and on ART adult HIV/ AIDS patients attending ART clinic in Dessie hospital.

Methods

A comparative cross-sectional study was conducted among pre-ART and on ART adult HIV/AIDS patients of Dessie Hospital. A total of 272 (136 from each group) study subjects were selected by using systematic random sampling. Stool sample was collected and processed using direct wet mount, formol-ether concentration technique and modified Ziehl-Neelson staining techniques. A structured questionnaire was used to collect data on Sociodemographic & associated risk factors. Data was entered and analyzed by using SPSS 16 software and logistic regressions were applied to assess any association between explanatory factors and outcome variables.

Results

The overall prevalence of IP in pre-ART and on-ART was 39% and 17.6%, respectively with significant decrease of intestinal parasite in the ART era (p < 0.001). All Cryptosporidium spps infections were found in the pre-ART patients and significantly associated for lower CD4 <200cells/mm³. Absence of toilet (AOR = 7.57; 95% CI = 1.3,44.22), source of water (AOR = 6.03; 95% CI = 1.14,31.98), living condition (AOR = 13.29, 95% CI = 5.14, 34.35); WHO stage (AOR = 6.06; 95% CI = 2.49,14.74) and ART status (AOR = 7.55; 95% CI = 3.24,17.59) have significant association with prevalence of intestinal parasite.

Conclusion

The overall prevalence of IP was differ by ART status and opportunistic parasite like cryptosporidium spps were found in low CD4 counts in ART naive patients. This study identified some environmental and some clinical finding as determinant factor for IP infections. Therefore, public health measures and adherence to ART should be strengthened to improve the quality of life of these patients.

Efficiency of diagnostic methods for correlation between prevalence of enteric protozoan parasites and HIV/AIDS status--an experience of a tertiary care hospital in East Delhi

Since the beginning of the AIDS pandemic, opportunistic infections have been recognized as common complications of HIV infection. Enteric protozoan parasitic infections are one of the leading causes of morbidity and mortality in HIV infected patients. The present study is, therefore, aimed to determine the prevalence of these parasites and study their association with immune status in HIV patients with emphasis on the correlation between various diagnostic techniques to give an accurate diagnosis to avoid empirical treatment. This prospective study, carried out between November 2009 and May 2010 included all HIV seropositive patients presenting with diarrhea to the ART center. A total of 64 stool samples were analyzed by wet mount examination, three different staining techniques, and antigen detection by ELISA for various enteric protozoan infections. Total prevalence of enteric protozoan parasites was 30%. Among the total cases, Cryptosporidium was seen in 12% cases followed by Giardia, E. histolytica and Isospora belli. The maximum diagnostic yield for coccidian parasites was with safranin-methylene blue staining technique. Parasitic burden contributes towards early morbidity in HIV infection. This study provides important information about prevalence of intestinal protozoan parasites in HIV infection. A combination of procedures should be carried out for the screening of stool specimens of HIV patients for better diagnosis and management.

2,4-Diamino-5-methyl-6-substituted arylthio-furo[2,3-d]pyrimidines as novel classical and nonclassical antifolates as potential dual thymidylate synthase and dihydrofolate reductase inhibitors

A novel classical antifolate N-{4-[(2,4-diamino-5-methyl-furo[2,3-d]pyrimidin-6-yl)thio]-benzoyl}-l-glutamic acid 5 and 11 nonclassical antifolates 6-16 were designed, synthesized, and evaluated as inhibitors of dihydrofolate reductase (DHFR) and thymidylate synthase (TS). The nonclassical compounds 6-16 were synthesized from 20 via oxidative addition of substituted thiophenols using iodine. Peptide coupling of the intermediate acid 21 followed by saponification gave the classical analog 5. Compound 5 is the first example, to our knowledge, of a 2,4-diamino furo[2,3-d]pyrimidine classical antifolate that has inhibitory activity against both human DHFR and human TS. The classical analog 5 was a nanomolar inhibitor and remarkably selective inhibitor of Pneumocystis carinii DHFR and Mycobacterium avium DHFR at 263-fold and 2107-fold, respectively, compared to mammalian DHFR. The nonclassical analogs 6-16 were moderately potent against pathogen DHFR or TS. This study shows that the furo[2,3-d]pyrimidine scaffold is conducive to dual human DHFR-TS inhibitory activity and to high potency and selectivity for pathogen DHFR.

The effect of 5-alkyl modification on the biological activity of pyrrolo[2,3-d]pyrimidine containing classical and nonclassical antifolates as inhibitors of dihydrofolate reductase and as antitumor and/or antiopportunistic infection agents

Novel classical antifolates (3 and 4) and 17 nonclassical antifolates (11-27) were synthesized as antitumor and/or antiopportunistic infection agents. Intermediates for the synthesis of 3, 4, and 11-27 were 2,4-diamino-5-alkylsubstituted-7H-pyrrolo[2,3-d]pyrimidines, 31 and 38, prepared by a ring transformation/ring annulation sequence of 2-amino-3-cyano-4-alkyl furans to which various aryl thiols were attached at the 6-position via an oxidative addition reaction using I2. The condensation of alpha-hydroxy ketones with malonodinitrile afforded the furans. For the classical analogues 3 and 4, the ester precursors were deprotected, coupled with diethyl-L-glutamate, and saponified. Compounds 3 (IC50 = 60 nM) and 4 (IC50 = 90 nM) were potent inhibitors of human DHFR. Compound 3 inhibited tumor cells in culture with GI50 500-fold selectivity over human DHFR. Analogue 17 was 50-fold more potent than trimethoprim and about twice as selective against T. gondii DHFR.

Short-term safety and tolerability of a once-daily fixed-dose abacavir-lamivudine combination versus twice-daily dosing of abacavir and lamivudine as separate components: findings from the ALOHA study

STUDY OBJECTIVE

To evaluate the short-term (12 wks) safety and tolerability of a once-daily, fixed-dose abacavir-lamivudine combination versus twice-daily dosing of the separate components, both with background antiretroviral therapy.

DESIGN

Phase IIIB, randomized, open-label, parallel-group, multicenter study.

SETTING

One hundred forty-six human immunodeficiency virus (HIV) clinics.

PATIENTS

Six hundred eighty antiretroviral therapy-naïve patients with HIV type 1 RNA greater than 1000 copies/ml at baseline.

INTERVENTION

Patients were randomly assigned in a 2:1 manner to receive either abacavir 600 mg-lamivudine 300 mg once/day or abacavir 300 mg twice/day and lamivudine 150 mg twice/day. Subjects were stratified based on choice of third or fourth antiretroviral drug (nucleoside reverse transcriptase inhibitor [NRTI], NNRTI, or protease inhibitor), assigned before randomization.

MEASUREMENTS AND MAIN RESULTS

The primary end point was occurrence of grades 2-4 adverse events and serious adverse events; abacavir hypersensitivity reactions were considered serious adverse events. Baseline characteristics were similar between the once-daily (455 patients) and twice-daily (225 patients) groups. The rates of all grades 2-4 adverse events were similar: once-daily 33% (150 patients), twice-daily 31% (69). A slightly larger proportion of patients in the twice-daily group experienced drug-related grades 2-4 adverse events: once-daily 10% (47), twice-daily 16% (36). Rates of all serious adverse events (once-daily 11% [49], twice-daily 10% [22]) and drug-related serious adverse events (once-daily 5% [21], twice-daily 8% [17]) were similar. The rate of suspected abacavir hypersensitivity reaction was 5.3% (once-daily 4.4% [20], twice-daily 7.1% [16]), with a higher rate for the NNRTI stratum of the twice-daily group (8.6% [10]) than in any other stratum (once-daily, NNRTI 4.3% [10]; twice-daily, protease inhibitor 5.6% [6]; once-daily, protease inhibitor 4.6% [10]).

CONCLUSION

In the short-term, the rates of adverse events in the once-daily and twice-daily groups appeared to be similar. The rate of suspected abacavir hypersensitivity reaction in the once-daily group was lower than the rate in the twice-daily group.