Blastocystis infections in HIV seropositive and seronegative adults - - PowerPoint PPT Presentation

Blastocystis infections in HIV seropositive and seronegative adults in Ghana: Prevalence, subtype distribution and health status

• Dr. Veronica Di Cristanziano

Institute of Virology University of Cologne

Blastocystis

Tan K 2008

Passenger or pathogen?

• Often the most commonly isolated organism in

parasitological surveys

• Originally considered a commensal of GI tract
• Redefined as an emerging pathogen
• Opportunistic pathogen in immunocompromised patients
• Clinical relevance and need of treatment is still

controversial

• „ For every report linking Blastocystis with clinical

manifestations there is another that find no such link“

(Stensvold and Clark 2016)

Blastocystis

• Anaerobic enteric protozoan of the group of Stramenopiles
• Worlwide distribution
• Asymptomatic colonization is very common
• Up to 17 subtypes (ST1-ST17) described with ST 1-9 found in humans
• Wide range of non-mammalian and mammalian hosts, including

humans

• Blastocystis hominis Blastocystis sp.
• Transmitted by the fecal-oral route

Host range and relative prevalence of Blastocystis STs

Wawrzyniak et al.2013 Stensvold and Clark 2016

Morphology

Tan K 2008

Roberts et al., K 2014

Epidemiology

• Recent surveys incorporated molecular methods which enable accurate detection and

characterization of Blastocystis

• Prevalence varies widely from country to country and within communities of the same country

− In industrialized countries from 0.5% to 30% − In developing countries from 30% to 76% − A prevalence of 100% was found in a Senegale population of children (highest prevalence ever reported worldwide; El Safadi et al. 2014)

Gastrointestinal manifestations

• Nonspecific GI symptoms (diarrhoea, abdominal pain, flatulence, nausea, vomiting,

weight loss)

• Blastocystis can be isolated from symtomatic and asymptomatic individuals with

almost equal prevalence

• Presence of more than 5 parasites per high-power field (x400) or oil immersion

(x1000) and absence of any other coinfecting pathogens

• So far no particular ST has beek linked consistently to disease
• ST4 isolates were found more common in symptomatic patients in Denmark and Spain
• Potential association between Blastocystis and irritabel bowel syndrome (IBS)

remains controversial in absence of large longitudinal cohort studies

− 71-year-old patient (farmer) − Diarrhea und erythematous maculopapular rash − Stool positive for Blastocystis − Metronidazole for 10 days − Rush resolved within one week

− 20-year old man − Recurrent GI and urticarial symptoms − Paromomycin + metronidazole

High-risk populations

• Immunucompromised health (HIV, under immunosuppressive

therapy)

• Children
• Poor hygiene practices
• Exposure to animals
• Consuptions of contaminated food or water

High-risk populations

• Immunucompromised health (HIV, under immunosuppressive

therapy)

• Children
• Poor hygiene practices
• Exposure to animals
• Consuptions of contaminated food or water

• Globally, 36.7 million people were living with HIV
• Sub-Saharan Africa remains most severely affected, with nearly 1 in every 25 adults

(4.2%) living with HIV and accounting for nearly two-thirds of the people living with HIV worldwide

HIV in Ghana

Some considerantions….

• The incidence of intestinal parasite infections reaches up to 95%

in HIV positive persons in developing countries

• These infections are caused both by protozoa and helminths and

their main clinical manifestation is diarrhoea

• Diarrhea is a major cause of morbidity in HIV-infected patients
• Parasitic infections could disturb the balance of anti-HIV immune

response and contribute to HIV replication which could accelerate progression to AIDS

• Data about Blastocystis prevalence and related occurrence of

clinical symptoms in HIV patients are limited, varying and sometimes contradictory

• Prevalence reported in HIV positive patients is not higher than

what is found in normal populations

• Few data about STs distribution

Blastocystis and HIV in the literature

• Albrecht et al. 1995 (Germany)
• Brites et al. 1997 (Brazil)
• Cimerma and al., 1999 (Brazil)
• Prasad et al. 2000 (India)
• Gassama et al., 2001
• Hailemariam et al. 2004 (Ethiopia)
• Zali et al 2004 (Iran)
• Stark et al. 2007 (Australia)
• Kurniawan et al. 2009 (Indonesia)
• Tan et al. 2009 (Malaysia)
• Alemu et al. 2011 (Ethiopia)
• Roka et al 2012 (Equatorial Guinea)
• Adamu et al. 2012 (Ethiopia)
• Tian LG et al., 2013

„Blastocystis has to be considered as an opportunistic parasite because it was identified only in HIV-infected patients, with higher prevalence in adults with diarrhae and in these cases it was not associated with other pathogens“

• The prevalence of Blastocystis among HIV-infected patients was lower than that among the controls
• Co-infection of HIV and Blastocystis was associated with favorable shifts in the immune profile of HIV-

infected individuals

Aims

• To deepen our understanding of the implications of

Blastocystis detection in person with and without HIV- infection living in Ghana

• STs, immune status, clinical symptoms, and co-infections

Study population

• 122 HIV positive patients presenting at the

HIV outpatient Department of the Komfo Anokye Teaching Hospital 54 with CD4+< 200 cells/µl 68 with CD4+>200 cells/µl

• 70 HIV negative blood donors from the same

hospital

Blastocystis prevalence

• 20% (14/70) in HIV negative

individuals

• 6.5% (8/122) in HIV positive

individuals − 7/68 with CD4+>200 cells/µl − 1/54 with CD4+< 200 cells/µl

P=0.008

Phylogenetic analysis

Comparison of sociodemographic and medical parameters of Blastocystis positive and negative participants

Parameters HIV positive subjects HIV negative subjects Total Blastocystis positive Blastocystis negative Total Blastocystis positive Blastocystis negative n (%) 122 8 (6.6)* 114 (93.4) 70 14 (20.0) 56 (80.0) Age in years, mean ± SD 40.3 ± 8.8 37.9 ± 12.9 40.5 ± 8.5 34.2 ± 13.1 § 36.6 ± 18.3 33.6 ± 11.5 Female gender, n (%) 89 (73.0) 7 (87.5) 82 (71.9) 43 (63.8) 9 (64.3) 34 (63.0) Access to tap water, n (%) 64 (52.5) 4 (50.0) 60 (52.6) 40 (60.6) 9 (64.3) 31 (59.6) Fridge/Freezer in household, n (%) 84 (68.9) 5 (62.5) 79 (69.3) 50 (75.8) 12 (85.7) 38 (73.0) CD4+ T cell count/µl, median (IQR) 289 (113- 496) 527 (367-651) 264 (110-489) * 1007 (859- 1261) § 869 (783-984) 1051 (915- 1360) * Gastrointestinal symptoms, n (%) 14 (11.5) 1 (12.5) 13 (11.4) 19 (29.2) 3 (21.4) 16 (31.4) BMIa (kg/m²), n (%) Low (≤18.5) Normal (>18.5-≤25) High (>25-≤30) 17 (14.2) 76 (63.3) 27 (22.5) 0 (0) 5 (62.5) 3 (37.5) 17 (15.18) 71 (63.39) 24 (21.43)

§

1 (1.7) 30 (52.6) 26 (45.6) 1 (8.33) 9 (75,00) 2 (16.67) * 21 (46.67) 24 (53.33) *p<0.05 for within group comparisons (Blastocystis positive/negative); §p<0.05 for between group comparisons (total HIV positive/total HIV negative); aBMI= Body Mass Index. p=0.025 p=0.016 p=0.035

GI symptoms and co-infections

• Only 4 partecipants with a positive result for Blastocystis

reported GI symptoms (diarrhea, abdominal pain, nausea or anorexia)

• Out of these, only one was HIV positive
• All was infected with ST1
• All were detected positive for other enteric pathogens (xTAG

GPP and FTD Viral gastroenteritis) ETEC, STEC, Shigella spp., Norovirus GII ETEC Salmonella spp. Adenovirus (HIV+)

Comparison of sociodemographic and medical parameters of Blastocystis positive and negative participants

Parameters HIV positive subjects HIV negative subjects Total Blastocystis positive Blastocystis negative Total Blastocystis positive Blastocystis negative n (%) 122 8 (6.6)* 114 (93.4) 70 14 (20.0) 56 (80.0) Age in years, mean ± SD 40.3 ± 8.8 37.9 ± 12.9 40.5 ± 8.5 34.2 ± 13.1 § 36.6 ± 18.3 33.6 ± 11.5 Female gender, n (%) 89 (73.0) 7 (87.5) 82 (71.9) 43 (63.8) 9 (64.3) 34 (63.0) Access to tap water, n (%) 64 (52.5) 4 (50.0) 60 (52.6) 40 (60.6) 9 (64.3) 31 (59.6) Fridge/Freezer in household, n (%) 84 (68.9) 5 (62.5) 79 (69.3) 50 (75.8) 12 (85.7) 38 (73.0) CD4+ T cell count/µl, median (IQR) 289 (113- 496) 527 (367-651) 264 (110-489) * 1007 (859- 1261) § 869 (783-984) 1051 (915- 1360) * Gastrointestinal symptoms, n (%) 14 (11.5) 1 (12.5) 13 (11.4) 19 (29.2) 3 (21.4) 16 (31.4) BMIa (kg/m²), n (%) Low (≤18.5) Normal (>18.5-≤25) High (>25-≤30) 17 (14.2) 76 (63.3) 27 (22.5) 0 (0) 5 (62.5) 3 (37.5) 17 (15.18) 71 (63.39) 24 (21.43)

§

1 (1.7) 30 (52.6) 26 (45.6) 1 (8.33) 9 (75,00) 2 (16.67) * 21 (46.67) 24 (53.33) *p<0.05 for within group comparisons (Blastocystis positive/negative); §p<0.05 for between group comparisons (total HIV positive/total HIV negative); aBMI= Body Mass Index.

Comparison of therapy related parameters of Blastocystis positive and negative participants within HIV positive persons

HIV positive (n=122) Parameters Blastocystis positive (n=8) Blastocystis negative (n=114) Time since diagnosis of HIV infection in months, mean ±SD 36.5 ± 39.77 24.26 ± 31.41 ART intake, n (%) 3 (37.50) 51 (44.74) Time since initiation of ART in months, mean ±SD 63.67 ± 28.22 40.11 ± 26.47 Co-trimoxazole intake, n (%) 4 (50.00%) 35 (30.70) Rifampicin intake, n (%) 2 (28.57) 10 (9.90) Intake of other antibiotics, n (%) 0 (0) 1 (0.88)

*p<0.05 (Blastocystis positive/negative), ART= Antiretroviral Therapy

All but one patients on ART received first-line therapy: Zidovudine or Tenofovir + Lamivudine + Efavirenz or Nevirapine

Factors associated with Blastocystis in HIV positive and negative persons

HIV pos, n=122 HIV neg, n=70 Univariate Multivariate Univariate Multivariate

Variable Total OR (96% CI) aOR (96% CI) Total OR (96% CI) aOR (96% CI) Age in years/10 4.03 ± 0.88 0.69 (0.27-1.60) 0.87 ( 0.36-1.94) 3.42 ± 1.31 1.18 (0.75-1.80) 1.24 (0.70-2.30) Gender Female Male 89 (73%) 33 (27%) 1 0.37 (0.02-2.17) 1 0.53 (0.02-4.30) 43 (63.2%) 25 (36.8%) 1 0.94 (0.26-3.14) 1 0.68 (0.14-2.99)

aBMI (kg/m²)

< 18.5 18.5-25 >25 14 (14.2%) 76 (63.3%) 27 (22.5%) 1 2.20 (0.43-9.63) 1 1.36 (0.20-7.66) 1 (1.8%) 30 (52.6%) 26 (45.6%) 1 0.18 (0.02-0.76) * 1 0.17 (0.02- 0.78) * CD4+ T cell count in count/µl /100 10.07 (8.59- 12.61) 1.20 (1.00-1.43) * 1.22 (1.00-1.50) * 2.89 (1.13-4.96) 0.82 (0.65-0.99) 0.86 (0.65-1.09) Receiving bART No Yes 68 (55.7%) 54 (44.3%) 1 0.74 (0.15-3.17) 1 0.56 (0.09-3.19) NA NA NA Intake of Rifampicin No Yes 7 (5.7&) 115 (94.3%) 1 2.57 (0.13-18.29) 1 2.95 (0.13-30.24) NA NA NA Intake of Co- trimoxazole No Yes 83 (68%) 39 (32%) 1 2.26 (0.51-10.05) 1 2.22 (0.43-11.60) NA NA NA

*p<0.05; aBMI=Body Mass Index;

bART= Antiretroviral Therapy

p=0.04 p=0.049

In summary

• The overall prevalence of Blastocystis as well as the prevalence in HIV negative

subjects only was lower compared to previous surveys in African countries by similar molecular approach Most patients resided in urban area (>50% have access to tap water) HIV+ and blood donors are regularly controlled for health status Adults only

• HIV negative patients showed a rate of infection significantly higher than HIV

positive patients (20% vs 6.6%, p=0.008)

• Within HIV positive patients:

− the prevalence of Blastocystis was higher in those individuals with CD4+ T cell count >200 cells/µl than in patients with CD4+ T cell counts <200 cells/µl (10.29 vs 1.85, p=0.076) − CD4+ T cell count was the only risk factor significantly positively associated with Blastocystis

• Within HIV negative patients, Blastocystis was positively associated with a

normal BMI

Our hyphotesis

• Blastocystis could be related with a good

health status

• Association with healthy body weight in HIV

negative patients and a good immune status in HIV positive patients

− 236 healthy individuals 20.3% − 13 patients with Chron´s disease 0% − 67 patients with ulcerative colitis 14.9% − Retrospective analysis of fecal DNA metagenomics data from 316 human samples − Blastocystis highly associated with certain bacterial communities

Blastocystis prevalence

BMI <25

− Something in the bacterial flora of lean individuals favor Blastocystis or that Blastocystis favor bacterial microbiota specific to lean individuals − It is possible that the correlation between leannes and high bacterial diversity requires Blastocystis to be significant Bacteroides Andersen et al. 2016

Analysis of 2154 publicy available metagenomic sample from 12 studies

• High-prevalence in the population (15%)
• Ability to cause persistent asymptomatic colonization
• Descreased presence in individuals with disbiosis associated with colorectal cancer and

Chron´s disease

• Inverse association between BMI and Blastocystis
• Correlation between Blastocystis and gut microbiome composition
• Blastocystis is a component of the heathy gut microbiome

− 48 Blastocystis-colonized patients and 48 Blastocystis-free subjects − Ion Torrent 16S rRNA gene sequencing to decipher the Blastocystis-associated gut microbiota − Higher bacterial diversity, higher abundance of Clostridia and lower abundance of Enterobacteriaceae in faecal microbiota of Blastocystis colonized patients − Blastocystis colonization is associated with a healthy gut microbiota

Conclusions

• First data about Blastocystis in Ghana
• Revision of its role as opportunistic agent
• Association with a better immune status jointly with

a healthy weight

• According to most recent data that Blastocystis may

be an indicator of intestinal and maybe even general health

Rossella D´Alfonso Federica Berrilli Rolf Kaiser

Elena Knops

Lavinia Fabeni Kirsten Eberhardt Albert Dompreh Fred Stephen Sarfo

Acknowledgments

Eva Heger

Thank you for your attention! Grazie per la vostra attenzione! Danke für Ihre Aufmerksamkeit !

Model for pathogenesis of Blastocystis