Albert Dompreh

This study assessed the diagnostic reliability of anti-Schistosoma serology in Ghanaian patients with and without concomitant human immunodeficiency virus (HIV) infection. Serological testing was performed on serum samples containing PCR-confirmed Schistosoma spp. DNA using a commercial enzyme-linked immunosorbent assay (ELISA; EUROIMMUN, Lübeck, Germany). Following real-time PCR confirmation of either Schistosoma mansoni or Schistosoma haematobium complex DNA, samples were subjected to anti-Schistosoma IgG and IgM serology in duplicate. Results were qualitatively interpreted as positive, uncertain, or negative; reproducible positive results across test runs were defined as “consistent,” while all other profiles were classified as “inconsistent”. Serological consistency was then correlated with patient demographic and clinical data, including age, gender, HIV status, CD4+ and CD8+ T-lymphocyte counts, CD4+/CD8+ ratios, and HIV viral loads. Of the 41 individuals with PCR-proven schistosomiasis (S. mansoni, n = 36; S. haematobium, n = 5) and no clinical signs of Katayama syndrome, 39 were HIV-positive. Among these 39 coinfected patients, consistently positive serology was recorded in 27 (69.2%) cases for IgG and 31 (79.5%) cases for IgM. Consistent IgG seropositivity was significantly associated with higher CD4+ (293 vs. 58 cells/µL, p = 0.009) and CD8+ (981.5 vs. 306 cells/µL, p = 0.007) T-lymphocyte counts. The association between higher CD4+ cell counts and consistent IgG reactivity remained robust in multivariable analysis (adjusted odds ratio = 2.04 per 100 cells/µL, p = 0.01). A non-significant trend in the same direction was observed for anti-Schistosoma IgM, whereas no other significant associations with epidemiological or medical factors were identified. In conclusion, the state of cellular immunity critically influences the reliability of serological schistosomiasis diagnostics in HIV-positive individuals. For patients with severe cellular immune depletion and suspected schistosomiasis, alternative diagnostic approaches, such as highly sensitive real-time PCR, should be strongly considered.

Objectives: This observational and cross-sectional study investigated differential associations between entero-invasive and non-entero-invasive enteric pathogens and HIV infection, considering socioeconomic, clinical and immunological aspects. In a Ghanaian population with a high prevalence of enteric pathogens, stool samples from people living with HIV (PLWH) were screened for Salmonella spp., Shigella spp./EIEC (enteroinvasive Escherichia coli), and Campylobacter jejuni as entero-invasive bacteria, for enteropathogenic E. coli (EPEC), enterotoxigenic E. coli (ETEC), and enteroaggregative E. coli (EAEC) as non-entero-invasive bacteria. Arcobacter butzleri, with uncertain enteropathogenicity, was also included. Methods: Stool samples from PLWH (with and without antiretroviral therapy) and HIV-negative controls were analyzed by real-time PCR for the presence and quantity of the selected enteropathogens. Results were correlated with socioeconomic, clinical, and immunological parameters. Results: The presence of Shigella spp. /EIEC in stool was both qualitatively and quantitatively associated with reduced CD4+ T lymphocyte counts and was qualitatively associated with clinically apparent diarrhea. EAEC showed a weak positive association with HIV infection, supported by a negative correlation between EAEC DNA quantity and CD4+ T lymphocyte counts. EPEC colonization was associated with HIV negativity, higher CD4+ T lymphocyte counts, and lower socioeconomic status. Abundance of Salmonella enterica was associated with clinically apparent diarrhea. Conclusions: This explorative, hypothesis-forming study suggests species- or pathovar-specific associations between enteric bacterial pathogens and HIV-related immunosuppression. Observed relationships with clinically apparent diarrhea largely align with findings from sub-Saharan African children, except for a more pronounced association between diarrhea and Salmonella in this cohort.

Background: Cryptosporidium spp. cause opportunistic infections in immunosuppressed individuals, such as people living with HIV (PLWH). However, the association between giardiasis and HIV infection remains uncertain. This study assessed co-infections in Ghanaian PLWH and HIV-negative individuals, analyzing socio-economic, clinical, and immunological implications, including the Giardia duodenalis assemblage and Cryptosporidium spp. sub-family levels. Methods: Stool samples from Ghanaian PLWH were tested using several real-time PCR assays targeting G. duodenalis at the species level and assemblages A and B to optimize diagnostic accuracy. GD60 gene-based Sanger sequencing was used for Cryptosporidium spp. subtyping. Results were correlated with anonymized patient data to evaluate interactions with HIV infection. Results: In PLWH, C. hominis Ib, C. hominis Ie, and C. parvum IIc were detected at similar frequencies, followed by C. hominis Ia, C. hominis Id, and C. parvum IIe in decreasing order. Only C. parvum IIc was repeatedly observed in individuals with CD4+ T cell counts above 200/µL, while other sub-families occurred preferentially in those with lower counts. C. hominis Ia and Ib were associated with PLWH not receiving antiretroviral therapy; C. hominis Ia was linked to recently diagnosed HIV infections. No relevant associations between G. duodenalis assemblages and HIV infection were found. Conclusions: Sub-families Ia and Ib of C. hominis preferentially occur in individuals with severe immunosuppression, while C. parvum IIc is also detectable in individuals with better immune function. The prevalence of giardiasis in Ghana appears to be influenced by factors other than HIV-induced immunosuppression.

Molecular diagnoses of Entamoeba histolytica and Strongyloides stercoralis in human samples are becoming increasingly common. To contribute to the ongoing standardization of molecular diagnostic approaches targeting these parasites, we compared three published E. histolytica- and S. stercoralis-specific real-time PCR assays in test comparisons without a reference standard. Latent class analysis (LCA) was used to calculate diagnostic accuracy estimations for the three compared assays per parameter. The comparison was conducted using stool samples from Ghanaian individuals. In the course of the assessment of 873 stool samples, the number of detected positive PCR results ranged from 10 to 15 for S. stercoralis and from 4 to 54 for E. histolytica depending on the applied assay. Diagnostic accuracy estimates of real-time PCR sensitivity for S. stercoralis and E. histolytica ranged from 89% to 100% and from 75% to 100%, respectively; diagnostic estimates of specificity ranged from 99% to 100% and from 94% to 100%, respectively. Diagnostic accuracy-adjusted prevalence estimates were 1.2% for S. stercoralis and 0.5% for E. histolytica. High cycle threshold values of real-time PCR > 35 showed a particularly reduced likeliness of reproducibility when applying competitor real-time PCR assays. There were no clear-cut differences in terms of diagnostic accuracy favoring either small-subunit ribosomal ribonucleic acid (SSU rRNA) gene sequences or the S. stercoralis dispersed repetitive sequence for S. stercoralis PCR. The same applied to the comparison of real-time PCRs targeting SSU rRNA gene sequences and the SSU rRNA episomal repeat sequence (SREPH) of E. histolytica. In conclusion, interchangeability of the compared real-time PCR assays was higher for the assessed S. stercoralis assays compared with the assessed E. histolytica assays. Regional diagnostic accuracy testing seems advisable before literature-adapted assays for rare tropical pathogens like S. stercoralis and E. histolytica are applied in different study regions.

Cystoisospora belli is a coccidian parasite commonly associated with enteric infections in immunocompromised individuals. The study was conducted to assess epidemiological, clinical, and immunological features of Ghanaian people living with HIV (human immunodeficiency virus) with and without antiretroviral therapy and molecular proof of C. belli-specific nucleic acid sequences in their stool samples. While C. belli was detected in 4.2% (n = 25) of the assessed HIV-positive patients, this was the case for only 1 (1.2%) Ghanaian control individuum without known HIV infection. Associations of cystoisosporiasis in Ghanaian HIV patients with reduced CD4+ T-lymphocyte counts and increased HIV viral loads, immune-activation as indicated by reduced CD4+/CD8+ T-lymphocyte ratios as well as higher expression of HLA-DR+ CD38+ on CD4+ T-lymphocytes, a symptom complex comprising diarrhea, weight loss and a reduced BMI, a trend towards not being on antiretroviral medication, and lacking access to food safety procedures like storing food in refrigerators were shown. The odds ratios (95% confidence intervals) of the associations were 4.47 (1.52–12.09) for the abundance of C. belli DNA and clinical diarrhea, 3.51 (1.42–9.12) for the abundance of C. belli DNA and CD4+ T-lymphocyte counts C. belli DNA and not having a refrigerator in the household. In conclusion, the assessment contributed to existing insight into the epidemiology of cystoisosporiasis in immunosuppressed individuals in resource-limited tropical high-endemicity areas. Chronic diarrhea among people living with HIV should prompt a diagnostic assessment for confirmation or exclusion of C. belli infections in such settings.

Although the etiological relevance of the detection of microsporidia in human stool samples remains uncertain, the immunological status of patients has been posited as an important determinant of potential clinical impact of these parasites. To further assess the interplay between the epidemiology of microsporidia and immunological markers, we conducted a study utilizing real-time PCR targeting Enterocytozoon bieneusi, Encephalitozoon cuniculi, Encephalitozoon hellem, and Encephalitozoon intestinalis, combined in a single fluorescence channel. The study involved a cohort of 595 clinically and immunologically well-characterized Ghanaian HIV patients, alongside 82 HIV-negative control individuals from Ghana. While microsporidial DNA was absent in HIV-negative controls, among people living with HIV, its prevalence was inversely correlated with CD4+ lymphocyte counts: 6.0% in those with >500 cells/µL, 9.5% in those with 200–499 cells/µL, 13.8% in those with 50–199 cells/µL, and 27.5% in those with <50 cells/µL, respectively. Correspondingly, microsporidia were more frequently detected in HIV patients who were not receiving antiretroviral therapy. There were no associations with clinical symptoms including gastroenteritis with the exception of a non-significant trend towards weight loss. HLA-DR+CD38+ on CD4+ T lymphocytes, a marker of immune activation, as well as Ki67, a marker of cell proliferation, were increased on CD4+ T lymphocytes in HIV patients with microsporidia, suggesting an immune response may be triggered. In conclusion, our assessment indicates a higher prevalence of microsporidia in the stool of Ghanaian HIV patients, which varies with their immunological status. However, given the lack of clear associations with clinical symptoms, the detection of microsporidia in the stool of HIV patients needs to be cautiously interpreted in clinical settings.

There is a paucity of information on the prevalence, risk factors, and clinical correlates of people living with HIV (PLWH) who are co-infected with Cryptosporidium spp. in the post-combined antiretroviral therapy era in Ghana. To provide such data, in this observational study, stool samples of 640 HIV-positive and 83 HIV-negative individuals in Ghana were screened for Cryptosporidium spp. Additionally, sociodemographic parameters, clinical symptoms, medication intake, and immunological parameters were assessed. The prevalence of Cryptosporidium spp. was 11.8% (n = 73) in HIV-positive and 1.2% (n = 1) in HIV-negative participants (p < 0.001). Within the group of HIV-positive participants, the prevalence reached 26.0% in patients with CD4+ T cell counts below 200 cells/µL and 46.2% in the subgroup with CD4+ T cell counts below 50 cells/µL. The frequencies of the clinical manifestation of weight loss and gastrointestinal symptoms were significantly higher in patients with Cryptosporidium spp. compared to those without co-infection (45.8% vs. 21.4%, p < 0.001 and 22.2% vs. 12.2%, p = 0.031, respectively). In the modern post-cART era, the acquisition of Cryptosporidium spp. among PLWH in Ghana is driven largely by the degree of immunosuppression. Access to cART and screening for Cryptosporidium spp. as part of routine care might help control and reduce the burden of the infection.

Background: There is a paucity of information on the contemporary burden, disease patterns, and immunological profile of people living with HIV who are co-infected with C. cayetanensis in the post-antiretroviral therapy era. Methods: For this cross-sectional study, stool samples of 640 HIV-positive and 83 HIV-negative individuals in Ghana were tested for C. cayetanensis. Additionally, sociodemographic parameters, clinical symptoms, medical drug intake, and immunological parameters were assessed. Results: The prevalence of C. cayetanensis was 8.75% (n = 56) in HIV-positive and 1.20% (n = 1) in HIV-negative participants (p = 0.015). Within the group of HIV-positive participants, the prevalence reached 13.6% in patients with CD4+ T cell counts below 200 cells/µl. Frequencies of the clinical manifestations of weight loss and diarrheal disease were significantly higher in patients with C. cayetanensis compared to those without co-infection (36.36% vs. 22.59%, p = 0.034 and 20.00% vs. 4.90%, p < 0.001, respectively). The expression of markers of immune activation and exhaustion of T lymphocyte sub-populations was significantly elevated in patients colonized with C. cayetanensis. Conclusions: In the modern post-combined antiretroviral therapy (cART) era, the acquisition of C. cayetanensis among PLWH in Ghana is driven largely by the immunosuppression profile characterized by high expression of markers of immune activation and immune exhaustion.

Both Schistosoma spp. (species) and Leishmania spp. are prevalent in Ghana in West Africa. However, little is known about their local occurrence in immunocompromised individuals. In the study presented here, the real-time PCR-(polymerase chain reaction-)based screening for repetitive DNA (deoxyribonucleotide acid) sequences from the genomes of Leishmania (L.) spp. and Schistosoma (S.) spp. was performed in the serum of HIV-(human immunodeficiency virus-)infected Ghanaian patients. In 1083 assessed serum samples from HIV-positive and HIV-negative Ghanian patients, Leishmania spp.-specific DNA was not detected, while the diagnostic accuracy-adjusted prevalence estimation suggested a 3.6% prevalence of the S. mansoni complex and a 0.5% prevalence of the S. haematobium complex. Associations of schistosomiasis with younger age, as well as with the male sex, could be shown but not with an HIV status. Weakly significant signals for the associations of schistosomiasis with an increased viral load, reduced CD4+ (CD = cluster of differentiation) T cell count, and a reduced CD4+/CD8+ ratio could be observed but was inconsistently lost in the case of the stratification on the species complex level. So, it is concluded that factors other than HIV status are more likely to have influenced the occurrence of Schistosoma spp. infections in the assessed Ghanaian patients. Potential associations between HIV infection-associated factors, such as the viral load and the immune status of the patients, for which weak signals were observed in this hypothesis-forming retrospective assessment, should be confirmed by prospective, sufficiently powered investigations.

Background: Recent studies demonstrated higher prevalence rates of Tropheryma whipplei (T. whipplei) in HIV positive than in HIV negative subjects. However, associations with the immune status in HIV positive participants were conflicting. Methods: For this cross-sectional study, stool samples of 906 HIV positive and 98 HIV negative individuals in Ghana were tested for T. whipplei. Additionally, sociodemographic parameters, clinical symptoms, medical drug intake, and laboratory parameters were assessed. Results: The prevalence of T. whipplei was 5.85% in HIV positive and 2.04% in HIV negative participants. Within the group of HIV positive participants, the prevalence reached 7.18% in patients without co-trimoxazole prophylaxis, 10.26% in subjects with ART intake, and 12.31% in obese participants. Frequencies of clinical symptoms were not found to be higher in HIV positive T. whipplei carriers compared to T. whipplei negative participants. Markers of immune activation were lower in patients colonized with T. whipplei. Multivariate regression models demonstrated an independent relationship of a high CD4+ T cell count, a low HIV-1 viral load, and an obese body weight with the presence of T. whipplei. Conclusions: Among HIV positive individuals, T. whipplei colonization was associated with a better immune status but not with clinical consequences. Our data suggest that the withdrawal of co-trimoxazole chemoprophylaxis among people living with HIV on stable cART regimen may inadvertently increase the propensity towards colonization with T. whipplei.