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Background: Malaria is a major world health issue and its continued burden is due, in part, to difficulties in the diagnosis of the illness. The World Health Organization recommends confirmatory testing using microscopy-based techniques or rapid diagnostic tests (RDT) for all cases of suspected malaria. In regions where Plasmodium species are indigenous, there are multiple etiologies of fever leading to misdiagnoses, especially in populations where HIV is prevalent and children. To determine the frequency of malaria infection in febrile patients over an 8-month period at the Regional Hospital in Bamenda, Cameroon, we evaluated the clinical efficacy of the Flourescence and Staining Technology (FAST) Malaria stain and ParaLens Advance TM microscopy system (FM) and compared it with conventional bright field microscopy and Giemsa stain (GS)., Methods: Peripheral blood samples from 522 patients with a clinical diagnosis of "suspected malaria" were evaluated using GS and FM methods. A nested PCR assay was the gold standard to compare the two methods. PCR positivity, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were determined., Results: Four hundred ninety nine samples were included in the final analysis. Of these, 30 were positive via PCR (6.01%) with a mean PPV of 19.62% and 27.99% for GS and FM, respectively. The mean NPV was 95.01% and 95.28% for GS and FM, respectively. Sensitivity was 26.67% in both groups and specificity was 92.78% and 96.21% for GS and FM, respectively. An increased level of diagnostic discrepancy was observed between technicians based upon skill level using GS, which was not seen with FM., Conclusions: The frequency of malarial infections confirmed via PCR among patients presenting with fever and other symptoms of malaria was dramatically lower than that anticipated based upon physicians' clinical suspicions. A correlation between technician skill and accuracy of malaria diagnosis using GS was observed that was less pronounced using FM. Additionally, FM increased the specificity and improved the PPV, suggesting this relatively low cost approach could be useful in resource-limited environments. Anecdotally, physicians were reluctant to not treat all patients symptomatically before results were known and in spite of a negative microscopic diagnosis, highlighting the need for further physician education to avoid this practice of overtreatment. A larger study in an area with a known high prevalence is being planned to compare the two microscopy methods against available RDTs. more...

Women in Cameroon are disproportionately burdened by HIV illness. Understanding the impact HIV has on women is essential for developing interventions to enhance their quality of life. Our aim was to explore and provide an in-depth understanding of the daily experiences of a sample of women living with HIV in Cameroon. Qualitative semi-structured in-depth interviews were conducted with women (N = 30) from the northwest region of Cameroon who self-reported being infected with HIV. Participants shared that they had multiple challenges in their daily experiences living with HIV. The themes that emerged included: (a) receiving an HIV diagnosis is traumatic, (b) living with HIV is a constant struggle, (c) limited resources and support cause problems, and (d) stigma and powerlessness exacerbate the impact of HIV. We provide insight into the daily experiences of HIV-infected women in Cameroon. Implications for improving health care and social services to women living with HIV in Cameroon are suggested., (Published by Elsevier Inc.) more...

Mild-to-moderate tobacco smoking is highly prevalent in HIV-infected individuals, and is known to exacerbate HIV pathogenesis. The objective of this study was to determine the specific effects of mild-to-moderate smoking on viral load, cytokine production, and oxidative stress and cytochrome P450 (CYP) pathways in HIV-infected individuals who have not yet received antiretroviral therapy (ART). Thirty-two human subjects were recruited and assigned to four different cohorts as follows: a) HIV negative non-smokers, b) HIV positive non-smokers, c) HIV negative mild-to-moderate smokers, and d) HIV positive mild-to-moderate smokers. Patients were recruited in Cameroon, Africa using strict selection criteria to exclude patients not yet eligible for ART and not receiving conventional or traditional medications. Those with active tuberculosis, hepatitis B or with a history of substance abuse were also excluded. Our results showed an increase in the viral load in the plasma of HIV positive patients who were mild-to-moderate smokers compared to individuals who did not smoke. Furthermore, although we did not observe significant changes in the levels of most pro-inflammatory cytokines, the cytokine IL-8 and MCP-1 showed a significant decrease in the plasma of HIV-infected patients and smokers compared with HIV negative non-smokers. Importantly, HIV-infected individuals and smokers showed a significant increase in oxidative stress compared with HIV negative non-smoker subjects in both plasma and monocytes. To examine the possible pathways involved in increased oxidative stress and viral load, we determined the mRNA levels of several antioxidant and cytochrome P450 enzymes in monocytes. The results showed that the levels of most antioxidants are unaltered, suggesting their inability to counter oxidative stress. While CYP2A6 was induced in smokers, CYP3A4 was induced in HIV and HIV positive smokers compared with HIV negative non-smokers. Overall, the findings suggest a possible association of oxidative stress and perhaps CYP pathway with smoking-mediated increased viral load in HIV positive individuals. more...

Background: The Strengthening Laboratory Management Toward Accreditation (SLMTA) programme is designed to build institutional capacity to help strengthen the tiered laboratory system. Most countries implement the SLMTA three-workshop series using a centralised model, whereby participants from several laboratories travel to one location to be trained together., Objectives: We assessed the effectiveness and cost of conducting SLMTA training in a decentralised manner as compared to centralised training., Methods: SLMTA was implemented in five pilot laboratories in Cameroon between October 2010 and October 2012 by means of a series of workshops, laboratory improvement projects and on-site mentorship. The first workshop was conducted in the traditional centralised approach. The second and third workshops were decentralised, delivered on-site at each of the five enrolled laboratories. Progress was monitored by repeated audits using the Stepwise Laboratory Quality Improvement Process Towards Accreditation (SLIPTA) checklist., Results: Audit scores for all laboratories improved steadily through the course of the programme. Median improvement was 11 percentage points after the first (centralised) training and an additional 24 percentage points after the second (decentralised) training. The estimated per-laboratory cost of the two training models was approximately the same at US$21 000. However, in the decentralised model approximately five times as many staff members were trained, although it also required five times the amount of trainer time., Conclusion: Decentralised SLMTA training was effective in improving laboratory quality and should be considered as an alternative to centralised training., Competing Interests: The authors declare that they have no financial or personal relationship(s) that may have inappropriately influenced them in writing this article. more...

Introduction: Facing the rapid scale-up of antiretroviral treatment (ART) programs in resource-limited settings, monitoring of treatment outcome is essential in order to timely detect and tackle drawbacks [1]., Methods: In a prospective cohort study, 300 consecutive patients starting first-line ART were enrolled between 2009 and2010 in a large HIV treatment centre in rural Cameroon. Patients were followed up for 12 months. Virologic failure was defined as a VL >1000 cop/mL at month 12. Besides CD4 and viral load (VL) analysis, HIV-1 drug resistance testing was performed in patients with VL>1000 copies (c)/mL plasma. In those patients and controls, minority HIV-1 drug resistance mutations at baseline, and plasma drug levels were analyzed in order to identify the risk factors for virologic failure., Results: Most enrolled patients (71%) were female. At baseline median CD4 cell count was 162/µL (IQR 59-259), median log10 VL was 5.4 (IQR 5.0-5.8) c/mL, and one-third of patients had World Health Organisation (WHO) stage 3 or 4; 30 patients died during follow-up. Among all patients who completed follow-up 38/238 had virologic failure. These patients were younger, had lower CD4 cell counts and more often had WHO stage 3 or 4 at baseline compared to patients with VL<1000c/mL. Sixty-three percent of failing patients (24/38) had at least one mutation associated with high-level drug resistance. The M184V mutation was the most frequently detected nucleoside reverse transcriptase inhibitor (NRTI) mutation (n=18) followed by TAMs (n=5) and multi-NRTI resistance mutations (n=4). The most commonly observed non-nucleoside reverse-transcriptase inhibitor (NNRTI) resistance mutations were K103N (n=10), Y181C (n=7), and G190A (n=6). Drug resistance mutations at baseline were detected in 12/65 (18%) patients, in 6 patients with and 6 patients without virological failure (p=0.77). Subtherapeutic NNRTI levels (OR 6.67, 95% CI 1.98-22.43, p<0.002) and poorer adherence (OR 1.54, 95% CI 1.00-2.39, p=0.05) were each associated with higher risk of virologic failure in the matched pair analysis. Unavailability of ART at the treatment centre was the single most common cause (37%) for incomplete adherence in these patients., Conclusions: Virologic failure after one year of first-line ART in rural Cameroon was not associated with transmitted drug resistance, but with reduced drug plasma levels and incomplete adherence. Strategies to assure adherence and uninterrupted drug supply are important factors for therapy success. more...

Background: Chronic hepatitis E virus (HEV) infections have recently been described in HIV-infected patients. Only few data are available for sub-Saharan Africa, where HIV and HEV are highly co-endemic, and where liver pathology is common in HIV-infected individuals., Objectives: To assess the prevalence of HEV viremia, anti-HEV antibodies, and serum aminotransferase levels in HIV patients in Ghana and Cameroon., Study Design: We retrospectively surveyed a cross-section of patients who were enrolled in cohort studies in Ghana (West Africa), and Cameroon (Central Africa). Plasma samples from 1029 HIV patients from Ghana and 515 patients from Cameroon including 214 children were analyzed for HEV-RNA by two reverse transcription PCR methods. In a subset of 791 patients, anti-HEV IgG and IgM antibodies were analyzed., Results: No HEV-RNA was detected in any of the plasma samples of 1544 patients. HEV seroprevalence was high in adult HIV patients from Ghana (45.3%, n=402) and Cameroon (14.2%, n=289), but low in pediatric HIV patients from Cameroon (2.0%, n=100). Elevations of alanine aminotransferase and aspartate aminotransferase levels were common in adult patients from Ghana (20.8% and 25.4%) and Cameroon (38.9% and 69.8%). The prevalence of hepatitis B virus surface antigen was 11.8% and of hepatitis C virus antibodies 2.5% in our adult Cameroonian study population., Conclusions: Acute or chronic HEV infections did not play a role in liver pathology in two HIV cohorts in Ghana and Cameroon. A better understanding of the epidemiology and genotype-specific characteristics of HEV infections in HIV patients in sub-Saharan Africa is needed., (Copyright © 2013 Elsevier B.V. All rights reserved.) more...

There is an urgent need for affordable CD4 enumeration to monitor HIV disease. CD4 enumeration is out of reach in resource-limited regions due to the time and temperature restrictions, technical sophistication, and cost of reagents, in particular monoclonal antibodies to measure CD4 on blood cells, the only currently acceptable method. A commonly used cost-saving and time-saving laboratory strategy is to calculate, rather than measure certain blood values. For example, LDL levels are calculated using the measured levels of total cholesterol, HDL, and triglycerides. Thus, identification of cell-free correlates that directly regulate the number of CD4(+) T cells could provide an accurate method for calculating CD4 counts due to the physiological relevance of the correlates. The number of stem cells that enter blood and are destined to become circulating CD4(+) T cells is determined by the chemokine CXCL12 and its receptor CXCR4 due to their influence on locomotion. The process of stem cell locomotion into blood is additionally regulated by cell surface human leukocyte elastase (HLE(CS)) and the HLE(CS)-reactive active α(1)proteinase inhibitor (α(1)PI, α(1)antitrypsin, SerpinA1). In HIV-1 disease, α(1)PI is inactivated due to disease processes. In the early asymptomatic categories of HIV-1 disease, active α(1)PI was found to be below normal in 100% of untreated HIV-1 patients (median=12 μM, and to achieve normal levels during the symptomatic categories. This pattern has been attributed to immune inactivation, not to insufficient synthesis, proteolytic inactivation, or oxygenation. We observed that in HIV-1 subjects with >220 CD4 cells/μl, CD4 counts were correlated with serum levels of active α(1)PI (r(2)=0.93, p<0.0001, n=26) and inactive α(1)PI (r(2)=0.91, p<0.0001, n=26). Administration of α(1)PI to HIV-1 infected and uninfected subjects resulted in dramatic increases in CD4 counts suggesting α(1)PI participates in regulating the number of CD4(+) T cells in blood. With stimulation, whole saliva contains sufficient serous exudate (plasma containing proteinaceous material that passes through blood vessel walls into saliva) to allow measurement of active α(1)PI and the correlation of this measurement is evidence that it is an accurate method for calculating CD4 counts. Briefly, sialogogues such as chewing gum or citric acid stimulate the exudation of serum into whole mouth saliva. After stimulating serum exudation, the activity of serum α(1)PI in saliva is measured by its capacity to inhibit elastase activity. Porcine pancreatic elastase (PPE) is a readily available inexpensive source of elastase. PPE binds to α(1)PI forming a one-to-one complex that prevents PPE from cleaving its specific substrates, one of which is the colorimetric peptide, succinyl-L-Ala-L-Ala-L-Ala-p-nitroanilide (SA(3)NA). Incubating saliva with a saturating concentration of PPE for 10 min at room temperature allows the binding of PPE to all the active α(1)PI in saliva. The resulting inhibition of PPE by active α(1)PI can be measured by adding the PPE substrate SA(3)NA. (Figure 1). Although CD4 counts are measured in terms of blood volume (CD4 cells/μl), the concentration of α(1)PI in saliva is related to the concentration of serum in saliva, not to volume of saliva since volume can vary considerably during the day and person to person. However, virtually all the protein in saliva is due to serum content, and the protein content of saliva is measurable. Thus, active α(1)PI in saliva is calculated as a ratio to saliva protein content and is termed the α(1)PI Index. Results presented herein demonstrate that the α(1)PI Index provides an accurate and precise physiologic method for calculating CD4 counts. more...