A comparison of screening tests for detection of high-grade cervical abnormalities in women living with HIV from Cameroon.

BACKGROUND: Women living with human immunodeficiency virus (WLWH), especially those living in low- and middle-income countries (LMIC), are at increased risk of cervical cancer. The optimal cervical-cancer screening strategy for WLWH has not been determined. We therefore conducted a pilot study of screening methods in WLWH living in Limbe, Cameroon. METHODS: Five-hundred sixty-six WLWH, aged 25-59 years, were enrolled. After self-collecting a cervicovaginal specimen, they underwent a pelvic exam, during which a provider also collected a cervical specimen and visual inspection after acetic acid (VIA) was performed. Both self- and provider-collected specimens were tested for high-risk HPV by the Xpert HPV Test (Cepheid, Sunnyvale, CA, USA), with the residual of the latter used for liquid-based cytology. Women testing HPV positive on either specimen and/or VIA positive were referred to colposcopy and biopsies. However, because of poor attendence for follow-up colposcopy for the screen positives due to civil strife and technical issues with biopsies, high-grade cytology and/or clinical diagnosis of cancer was used as the primary high-grade cervical abnormality endpoint. Clinical performances for high-grade cervical abnormality of HPV testing and VIA for screening WLWH, and the most carcinogenic HPV genotypes and/or VIA to triage high-risk HPV-positive WLWH, were evaluated. RESULTS: Four-hundred eighty-seven (86.0%) WLWH had results for HPV testing on both specimen, VIA, and cytology and were included in the analysis. Forty-nine (10.1%) had a high-grade cervical abnormality. HPV testing on provider- and self-collected specimens was more sensitive than VIA (95.9 and 91.8% vs. 43.8%, respectively, p < 0.01 for both comparisons) for identifying women with high-grade cervical abnormalities. HPV testing on provider- and self-collected specimens was less specific than VIA (57.5 and 51.6% vs. 89.7%, respectively, p < 0.01 for both comparisons) for identifying women with high-grade cervical abnormalities; HPV testing on provider-collected specimens was more specific than on self-collected specimens (p < 0.01). Among HPV-positive women, HPV16/18/45 detection or VIA positivity had a sensitivity and positive predictive value of 73.5 and 29.0%, respectively, for provider-collected specimens and 68.8 and 22.9%, respectively, for self-collected specimens for high-grade cervical abnormalities. CONCLUSIONS: HPV testing was more sensitive but less specific than VIA for detection of high-grade cervical abnormality in WLWH. Improved triage methods for HPV-positive WLWH are needed. TRIAL REGISTRATION: NCT04401670 (clinicaltrials.gov); retrospectively registered on May 26, 2020.

Cervical human papillomavirus DNA detection in women living with HIV and HIV-uninfected women living in Limbe, Cameroon.

BACKGROUND: There are limited data on cervical HPV prevalence in Cameroon and none from its Anglophone region. We investigated cervical HPV prevalence in HIV-uninfected (HIV[-]) and HIV-infected (WLWH) women living in the region. METHODS: A convenience sample of consecutively recruited HIV[-] women (n = 295) and women living with HIV (WLWH) (n = 560) attending the Limbé Regional Hospital were enrolled into a cervical screening study. Women underwent screening that included HPV testing of self-collected and provider-collected specimens. We calculated the HPV prevalence by HIV status, overall and stratified by age, and among WLWH, stratified by CD4 counts. We compared the concordance for the detection of HPV between self- and provider-collected specimens. RESULTS: Crude HPV prevalence was 21.69 % (95 % confidence interval [95 %CI] = 17.21-26.48 %) for HIV[-] women and 46.43 % (95 %CI = 42.24-50.66 %) for WLWH (p < 0.001). Among WLWH, older age (ptrend = 0.01) and higher CD4 counts (ptrend = 0.007) were associated with lower HPV prevalence. There was a good-to-excellent agreement for HPV detection between specimens, and self-collected were more likely than provider-collected specimens to test HPV positive, for all women and stratified by HIV status. CONCLUSIONS: HIV-related immunosuppression was a risk factor for HPV prevalence in this population. HPV testing of self-collected specimens appeared to be less specific than HPV testing of provider-collected specimens.

Screening for cervical cancer among HIV-positive and HIV-negative women in Cameroon using simultaneous co-testing with careHPV DNA testing and visual inspection enhanced by digital cervicography: Findings of initial screening and one-year follow-up.

OBJECTIVE: The World Health Organization (WHO)'s cervical cancer screening guidelines for limited-resource settings recommend sequential screening followed by same-day treatment under a "screen-and-treat" approach. We aimed to (1) assess feasibility and clinical outcomes of screening HIV-positive and HIV-negative Cameroonian women by pairing visual inspection with acetic acid and Lugol's iodine enhanced by digital cervicography (VIA/VILI-DC) with careHPV, a high-risk human papillomavirus (HR-HPV) nucleic acid test designed for low-resource settings; and (2) determine persistence of HR-HPV infection after one-year follow-up to inform optimal screening, treatment, and follow-up algorithms. METHODS: We co-tested 913 previously unscreened women aged ≥30years and applied WHO-recommended treatment for all VIA/VILI-DC-positive women. Baseline prevalence of HR-HPV and HIV were 24% and 42%, respectively. RESULTS: On initial screen, 44 (5%) women were VIA/VILI-DC-positive, of whom 22 had HR-HPV infection, indicating 50% of women screened false-positive and would have been triaged for unnecessary same-day treatment. VIA/VILI-DC-positive women with HIV infection were three times more likely to be HR-HPV-positive than HIV-negative women (65% vs. 20%). All women positive for either VIA/VILI-DC or HR-HPV (n=245) were invited for repeat co-testing after one year, of which 136 (56%) returned for follow-up. Of 122 women who were HR-HPV-positive on initial screen, 60 (49%) re-tested negative, of whom 6 had received treatment after initial screen, indicating that 44% of initially HR-HPV-positive women spontaneously cleared infection after one year without treatment. Women with HIV were more likely to remain HR-HPV-positive on follow-up than HIV-negative women (61% vs. 22%, p<0.001). Treatment was offered to all VIA/VILI-DC positive women on initial screen, and to all women screening VIA/VILI-DC or HR-HPV positive on follow-up. CONCLUSIONS: We found careHPV co-testing with VIA/VILI-DC to be feasible and valuable in identifying false-positives, but careHPV screening-to-result time was too long to inform same-day treatment.

Comparative evaluation of a rapid diagnostic test, an antibody ELISA, and a pLDH ELISA in detecting asymptomatic malaria parasitaemia in blood donors in Buea, Cameroon.

BACKGROUND: In malaria endemic areas, infected blood donors serve as a source of infection to blood recipients, which may adversely affect their prognosis. This necessitates the proper screening of blood to be used for transfusion in these areas. The purpose of this study was to determine the prevalence of malaria parasitaemia in blood donors in Buea, Cameroon, and to evaluate the performance of a rapid diagnostic test (RDT), a malaria antibody enzyme-linked immunosorbent assay (ELISA), and a Plasmodium lactate dehydrogenase (pLDH) ELISA in the detection of asymptomatic malaria parasitaemia in the target population. METHODS: In a prospective study conducted between September 2015 and June 2016, 1 240 potential blood donors were enrolled. The donors were screened for malaria parasites using Giemsa microscopy (GM) and a RDT. A sub-sample of 184 samples, comprising 88 positive and 96 negative samples, were selected for the evaluation of the pLDH ELISA and the antibody ELISA. The chi-square test and correlation analysis were performed as part of the statistical analyses. The statistical significance cut-off was set at P < 0.05. RESULTS: The prevalence of malaria parasitaemia in this study was found to be 8.1% (95% CI: 6.6 - 9.7). The prevalence was not observed to be dependent on the age or sex of the participants. The RDT had a sensitivity (88.0%), specificity (99.1%), and negative predictive value (99.0%) higher than the ELISAs. The performance of the pLDH ELISA, which demonstrated the highest positive predictive value (91.6%), was generally comparable to the RDT. The sensitivity was lowest with the antibody ELISA (69.9%), which also demonstrated the highest false positive and false negative rates. The detection threshold for the pLDH (three parasites/µl) was lower compared to the RDT (50 - 60 parasites/µl). Non-significant positive correlations were observed between the parasite density and the pLDH titers and malaria antibody titers. CONCLUSIONS: Overall, the RDT and the pLDH ELISA demonstrated a perfectly correlated agreement with GM, meanwhile the antibody ELISA demonstrated a substantially correlated agreement with GM. The pLDH is therefore recommended for mass screening of blood (to detect malaria parasitaemia) for transfusions in the study area. However, where this is not feasible, an RDT will suffice.