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 Often the most commonly isolated organism in o parasitological surveys Originally considered a commensal of GI tract o Redefined as an emerging pathogen o Opportunistic pathogen in immunocompromised patients o Clinical relevance and need of treatment is still o controversial „ For every report linking Blastocystis with clinical o manifestations there is another that find no such link“ (Stensvold and Clark 2016) Tan K 2008 Passenger or pathogen?
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
− 20-year old man − Recurrent GI and urticarial symptoms − Paromomycin + metronidazole − 71-year-old patient (farmer) − Diarrhea und erythematous maculopapular rash − Stool positive for Blastocystis − Metronidazole for 10 days − Rush resolved within one week
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 P=0.008 • 6.5% (8/122) in HIV positive individuals − 7/68 with CD4+>200 cells/µl − 1/54 with CD4+< 200 cells/µl
Phylogenetic analysis
Comparison of sociodemographic and medical parameters of Blastocystis positive and negative participants Parameters HIV positive subjects HIV negative subjects Total Blastocystis Blastocystis Total Blastocystis Blastocystis positive negative positive negative n (%) 122 8 (6.6)* 114 (93.4) 70 14 (20.0) 56 (80.0) Age in years, mean ± 40.3 ± 8.8 37.9 ± 12.9 40.5 ± 8.5 34.2 ± 13.1 § 36.6 ± 18.3 33.6 ± 11.5 SD 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 84 (68.9) 5 (62.5) 79 (69.3) 50 (75.8) 12 (85.7) 38 (73.0) household, n (%) CD4+ T cell count/µl, 289 (113- 527 (367-651) 264 (110-489) 1007 (859- 869 (783-984) 1051 (915- p =0.025 1261) § median (IQR) 496) * 1360) * p =0.035 Gastrointestinal 14 (11.5) 1 (12.5) 13 (11.4) 19 (29.2) 3 (21.4) 16 (31.4) symptoms, n (%) BMI a (kg/m²), n (%) § * Low (≤18.5) 17 (14.2) 0 (0) 17 (15.18) 1 (1.7) 1 (8.33) 0 p =0.016 Normal (>18.5 - ≤25) 76 (63.3) 5 (62.5) 71 (63.39) 30 (52.6) 9 (75,00) 21 (46.67) High (>25 - ≤30) 27 (22.5) 3 (37.5) 24 (21.43) 26 (45.6) 2 (16.67) 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); a BMI= Body Mass Index.
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 Blastocystis Total Blastocystis Blastocystis positive negative positive negative n (%) 122 8 (6.6)* 114 (93.4) 70 14 (20.0) 56 (80.0) Age in years, mean ± 40.3 ± 8.8 37.9 ± 12.9 40.5 ± 8.5 34.2 ± 13.1 § 36.6 ± 18.3 33.6 ± 11.5 SD 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 84 (68.9) 5 (62.5) 79 (69.3) 50 (75.8) 12 (85.7) 38 (73.0) household, n (%) CD4+ T cell count/µl, 289 (113- 527 (367-651) 264 (110-489) 1007 (859- 869 (783-984) 1051 (915- 1261) § median (IQR) 496) * 1360) * Gastrointestinal 14 (11.5) 1 (12.5) 13 (11.4) 19 (29.2) 3 (21.4) 16 (31.4) symptoms, n (%) BMI a (kg/m²), n (%) § * Low (≤18.5) 17 (14.2) 0 (0) 17 (15.18) 1 (1.7) 1 (8.33) 0 Normal (>18.5 - ≤25) 76 (63.3) 5 (62.5) 71 (63.39) 30 (52.6) 9 (75,00) 21 (46.67) High (>25 - ≤30) 27 (22.5) 3 (37.5) 24 (21.43) 26 (45.6) 2 (16.67) 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); a BMI= Body Mass Index.
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