Harry van Loen

Use of Pentamidine As Secondary Prophylaxis to Prevent Visceral Leishmaniasis Relapse in HIV Infected Patients, the First Twelve Months of a Prospective Cohort Study

Background Visceral leishmaniasis (VL) has become an important opportunistic infection in persons with HIV-infection in VL-endemic areas. The co-infection leads to profound immunosuppression and high rate of annual VL recurrence. This study assessed the effectiveness, safety and feasibility of monthly pentamidine infusions to prevent recurrence of VL in HIV co-infected patients. Methods A single-arm, open-label trial was conducted at two leishmaniasis treatment centers in northwest Ethiopia. HIV-infected patients with a VL episode were included after parasitological cure. Monthly infusions of 4mg/kg pentamidine-isethionate diluted in normal-saline were started for 12months. All received antiretroviral therapy (ART). Time-to-relapse or death was the primary end point. Results Seventy-four patients were included. The probability of relapse-free survival at 6months and at 12 months was 79% and 71% respectively. Renal failure, a possible drug-related serious adverse event, occurred in two patients with severe pneumonia. Forty-one patients completed the regimen taking at least 11 of the 12 doses. Main reasons to discontinue were: 15 relapsed, five died and seven became lost to follow-up. More patients failed among those with a CD4+cell count ≤ 50cells/μl, 5/7 (71.4%) than those with counts above 200 cells/μl, 2/12 (16.7%), (p = 0.005). Conclusion Pentamidine secondary prophylaxis led to a 29% failure rate within one year, much lower than reported in historical controls (50%-100%). Patients with low CD4+cell counts are at increased risk of relapse despite effective initial VL treatment, ART and secondary prophylaxis. VL should be detected and treated early enough in patients with HIV infection before profound immune deficiency installs.

Malaria Incidence and Prevalence Among Children Living in a Peri-Urban Area on the Coast of Benin, West Africa: A Longitudinal Study

Clinical malaria incidence was determined over 18 months in a cohort of 553 children living in a peri-urban area near Cotonou. Three cross-sectional surveys were also carried out. Malaria incidence showed a marked seasonal distribution with two peaks: the first corresponding to the long rainy season, and the second corresponding to the overflowing of Lake Nokoue. The overall Plasmodium falciparum incidence rate was estimated at 84/1,000 person-months, and its prevalence was estimated at over 40% in the two first surveys and 68.9% in the third survey. Multivariate analysis showed that girls and people living in closed houses had a lower risk of clinical malaria. Bed net use was associated with a lower risk of malaria infection. Conversely, children of families owing a pirogue were at higher risk of clinical malaria. Considering the high pyrethroids resistance, indoor residual spraying with either a carbamate or an organophospate insecticide may have a major impact on the malaria burden.

Adding artesunate to sulphadoxine-pyrimethamine greatly improves the treatment efficacy in children with uncomplicated falciparum malaria on the coast of Benin, West Africa

BackgroundBenin has recently shifted its national antimalarial drug policy from monotherapies to combinations containing artemisinin derivatives. When this decision was taken, the available information on alternatives to chloroquine and sulphadoxine-pyrimethamine, the first- and second-line treatment, was sparse.MethodsIn 2003 – 2005, before the drug policy change, a randomized, open-label, clinical trial was carried out on the efficacy of chloroquine, and sulphadoxine-pyrimethamine alone or combined with artesunate, with the aim of providing policy makers with the information needed to formulate a new antimalarial drug policy. Children between six and 59 months of age, with uncomplicated malaria and living in the lagoon costal area in southern Benin, were randomly allocated to one of the three study arms and followed up for 28 days.ResultsTreatment failure (PCR corrected) was significantly lower in the artesunate + sulphadoxine-pyrimethamine group (4/77, 5.3%) than in chloroquine group(51/71, 71.8%) or the sulphadoxine-pyrimethamine alone group (30/70, 44.1%) (p < 0.001). Despite high sulphadoxine-pyrimethamine failure, its combination with artesunate greatly improved treatment efficacy.ConclusionIn Benin, artesunate + sulphadoxine-pyrimethamine is efficacious and could be used when the recommended artemisinin-based combinations (artemether-lumefantrine and amodiaquine-artesunate) are not available. However, because sulphadoxine-pyrimethamine is also used in pregnant women as intermittent preventive treatment, its combination with artesunate should not be widely employed in malaria patients as this may compromise the efficacy of intermittent preventive treatment.

Challenges of non-commercial multicentre North-South collaborative clinical trials

The last decade has witnessed a substantial increase of multi‐centre, public health‐oriented clinical trials in poor countries. However, non‐commercial research groups have less staff and financial resources than traditional commercial sponsors, so the trial teams have to be creative to comply with Good Clinical Practices (GCP) requirements. According to the recent experience of a large multicentre trial on antimalarials, major challenges result from the complexity of multiple ethical review, the costs of in‐depth monitoring at several sites, setting up an adequate Good Clinical Laboratory Practices (GCLP) framework, lack of insurers in host countries, and lack of adequate non‐commercial data management software. Public research funding agencies need to consider these challenges in their funding policies. They also could support common spaces where North‐South collaborative research groups may share critical information, such as on research insurance and open‐source, GCP‐compliant software. WHO should update its GCP guidelines, which date back to 1995, to incorporate the perspectives and needs of non‐commercial clinical research.

Glucose-6-phosphate dehydrogenase deficiency, chlorproguanil-dapsone with artesunate and post-treatment haemolysis in African children treated for uncomplicated malaria.

BackgroundMalaria is a leading cause of mortality, particularly in sub-Saharan African children. Prompt and efficacious treatment is important as patients may progress within a few hours to severe and possibly fatal disease. Chlorproguanil-dapsone-artesunate (CDA) was a promising artemisinin-based combination therapy (ACT), but its development was prematurely stopped because of safety concerns secondary to its associated risk of haemolytic anaemia in glucose-6-phosphate dehydrogenase (G6PD)-deficient individuals. The objective of the study was to assess whether CDA treatment and G6PD deficiency are risk factors for a post-treatment haemoglobin drop in African children <5 years of age with uncomplicated malaria.MethodsThis case–control study was performed in the context of a larger multicentre randomized clinical trial comparing safety and efficacy of four different ACT in children with uncomplicated malaria. Children, who after treatment experienced a haemoglobin drop ≥2 g/dl (cases) within the first four days (days 0, 1, 2, and 3), were compared with those without an Hb drop (controls). Cases and controls were matched for study site, sex, age and baseline haemoglobin measurements. Data were analysed using a conditional logistic regression model.ResultsG6PD deficiency prevalence, homo- or hemizygous, was 8.5% (10/117) in cases and 6.8% (16/234) in controls (p = 0.56). The risk of a Hb drop ≥2 g/dl was not associated with either G6PD deficiency (adjusted odds ratio (AOR): 0.81; p = 0.76) or CDA treatment (AOR: 1.28; p = 0.37) alone. However, patients having both risk factors tended to have higher odds (AOR: 11.13; p = 0.25) of experiencing a Hb drop ≥2 g/dl within the first four days after treatment, however this finding was not statistically significant, mainly because G6PD deficient patients treated with CDA were very few. In non-G6PD deficient individuals, the proportion of cases was similar between treatment groups while in G6PD-deficient individuals, haemolytic anaemia occurred more frequently in children treated with CDA (56%) than in those treated with other ACT (29%), though the difference was not significant (p = 0.49).ConclusionThe use of CDA for treating uncomplicated malaria may increase the risk of haemolytic anaemia in G6PD-deficient children.

Experiences and Lessons from a Multicountry NIDIAG Study on Persistent Digestive Disorders in the Tropics.

Persistent digestive disorders can be defined as any diarrhea (i.e., three or more loose stools per day) lasting for at least two weeks and/or abdominal pain that persists for two weeks or longer [1–3]. These disorders cause considerable morbidity and human suffering, and hence, are reasons why people might seek primary health care. However, in resource-constrained settings of the tropics and subtropics, accurate point-of-care diagnostics are often lacking and treatment is empiric, particularly in remote rural areas with no laboratory infrastructure. As a result, the relative contribution of selected pathogens to the syndrome of persistent digestive disorders is poorly understood, and evidence-based guidelines for patient management in different social-ecological settings are scarce [4–6]. In order to improve the clinical management of patients with disorders caused by neglected tropical diseases (NTDs), the European Commission (EC) funded a five-year study—the Neglected Infectious diseases DIAGnosis (NIDIAG) research consortium. The overarching goal of the NIDIAG consortium is to develop and validate patient-centered diagnosis–treatment guidelines for use at the primary health care level in low- and middle-income countries (http://www.nidiag.org) [3,7–9]. Emphasis is placed on three syndromes: (i) persistent digestive disorders described here; (ii) persistent fever; and (iii) neurological disorders, the latter two of which are detailed in companion pieces published in the same issue of PLOS Neglected Tropical Diseases. With regard to the study on persistent digestive disorders, the main aims are (i) to identify the most important NTDs and other infectious agents that give rise to this clinical syndrome, including their relative frequency; (ii) to assess and compare the accuracy of different diagnostic methods; and (iii) to determine clinical responses to commonly employed empiric treatment options for persistent digestive disorders [9]. To this end, a case–control study has been implemented in four countries: Cote d’Ivoire and Mali in West Africa and Indonesia and Nepal in Asia. An integral part of the NIDIAG consortium is to ensure that good clinical practice (GCP) and good clinical laboratory practice (GCLP) are adhered to while conducting the studies [10,11]. A quality assurance system, which included the development and implementation of a set of standard operating procedures (SOPs), along with on-the-spot staff training and internal and external quality control activities, has been developed at the project level and introduced at each study site. The development of, and adherence to, SOPs within harmonized study protocols were considered crucial steps for maximizing the integrity of laboratory and clinical data across study settings. They also provided the basis on which quality control activities could be performed. For Which Procedures Have SOPs Been Developed? For the study on persistent digestive disorders, 33 specific SOPs have been developed (Supporting Information). As summarized in Table 1, detailed steps on clinical and laboratory procedures, data management, and quality assurance were described. With regard to clinical investigations, SOPs on history taking and clinical examination, assessing inclusion and exclusion criteria, patient recruitment, and study flow were developed (S1-S6). Detailed instructions on how to perform a set of laboratory diagnostic techniques for the detection of helminth and intestinal protozoa infections were included in the laboratory SOPs. Different conventional stool microscopy techniques were combined with more recent rapid antigen detection tests to encompass a broad spectrum of potentially implicated pathogens with high diagnostic accuracy (S7-S20). An overview of the employed diagnostic methods is provided in Table 2. Pertaining to data management, SOPs on completion of case report forms (CRFs) and on various activities (such as data entry, data cleaning, querying, database locking, and backing up data) were also included. To ensure quality control, SOPs on internal quality control activities, external monitoring, and laboratory supervision visits were jointly developed for the three syndromes (S21-S33). Table 1 Set of standard operating procedures (SOPs) used in the NIDIAG study on persistent digestive disorders. Table 2 Laboratory diagnostic techniques used and internally compared in the NIDIAG study on persistent digestive disorders. Of note, all SOPs were developed in English (for use in Nepal) and subsequently translated into French (for use in Cote d’Ivoire and Mali) and Bahasa Indonesia (for use in Indonesia). This comprehensive set of closely interconnected SOPs—which provides guidance on all essential procedures from the first presentation of an individual at a health care center until the final processing of all patient and laboratory data—is displayed in Fig 1. Fig 1 Principal elements of the NIDIAG digestive study and the respective standard operating procedures (SOPs) used. How Was the Development of SOPs Coordinated, and Which Quality Control Measures Were Adopted? The development and harmonization of the various SOPs was coordinated by the quality assurance group of the NIDIAG consortium and the trial management group (TMG) of the digestive syndrome study and followed a standard template and consortium-wide guidelines stipulated in the SOP entitled “SOP on SOP” (S24). This allowed different authors with varied background and writing styles to convey key messages and pass on their expert knowledge in a systematic, standardized manner for the benefit of the end user of all the SOPs. In addition, it provided clear instructions on how the SOPs should be numbered, reviewed, and approved to allow for strict version control. The authors of the SOPs were chosen from within the NIDIAG consortium, and allocation of topics was based on expertise and track record in the clinical, laboratory, data management, and quality assurance components of the study. Experts in the field, at the bench, and at the bedside carefully reviewed and revised the draft SOPs. Before the start of recruitment, local clinical and laboratory teams were trained on the set of SOPs through two hands-on workshops lasting three days each that were conducted on site by relevant experts of the NIDIAG consortium. During these workshops, feedback from the local partners was incorporated to refine the already developed SOPs, and additional SOPs were jointly developed to meet specific demands of local clinical, epidemiologic, and laboratory conditions. For example, in Indonesia, where Kinyoun staining was not available, an SOP pertaining to a slightly modified acid-fast staining technique was developed for the local team instead. Finally, once an SOP was finalized, a member of the TMG would approve it. A quality assurance member of the NIDIAG consortium was tasked to compile and keep updated the final set of SOPs and ensure that the latest versions were available on the NIDIAG intranet for distribution among the different country partners.

Long-term Clinical Outcomes in Visceral Leishmaniasis/Human Immunodeficiency Virus–Coinfected Patients During and After Pentamidine Secondary Prophylaxis in Ethiopia: A Single-Arm Clinical Trial

We conducted a single-arm clinical trial in Ethiopian visceral leishmaniasis/HIV-coinfected patients using pentamidine secondary prophylaxis. The 2-year risk of relapse was 37%. Patients reaching a CD4 count >200 cells/µL after 12 months of prophylaxis can safely discontinue pentamidine.

Clinical spectrum, etiology, and outcome of neurological disorders in the rural hospital of Mosango, the Democratic Republic of Congo

Abstract. There is little published information on the epidemiology of neurological disorders in rural Central Africa, although the burden is considered to be substantial. This study aimed to investigate the pattern, etiology, and outcome of neurological disorders in children > 5 years and adults admitted to the rural hospital of Mosango, province of Kwilu, Democratic Republic of Congo, with a focus on severe and treatable infections of the central nervous system (CNS). From September 2012 to January 2015, 351 consecutive patients hospitalized for recent and/or ongoing neurological disorder were prospectively evaluated by a neurologist, subjected to a set of reference diagnostic tests in blood or cerebrospinal fluid, and followed-up for 3–6 months after discharge. No neuroimaging was available. Severe headache (199, 56.7%), gait/walking disorders (97, 27.6%), epileptic seizure (87, 24.8%), and focal neurological deficit (86, 24.5%) were the predominant presentations, often in combination. Infections of the CNS were documented in 63 (17.9%) patients and mainly included bacterial meningitis and unspecified meningoencephalitis (33, 9.4%), second-stage human African trypanosomiasis (10, 2.8%), and human immunodeficiency virus (HIV)-related neurological disorders (10, 2.8%). Other focal/systemic infections with neurological manifestations were diagnosed in an additional 60 (17.1%) cases. The leading noncommunicable conditions were epilepsy (61, 17.3%), psychiatric disorders (56, 16.0%), and cerebrovascular accident (23, 6.6%). Overall fatality rate was 8.2% (29/351), but up to 23.8% for CNS infections. Sequelae were observed in 76 (21.6%) patients. Clinical presentations and etiologies of neurological disorders were very diverse in this rural Central African setting and caused considerable mortality and morbidity.

A head-to-head comparison of four artemisinin-based combinations for treating uncomplicated malaria in African children : a randomized trial

Artemisinin-based combination therapies (ACTs) are the mainstay for the management of uncomplicated malaria cases. However, up-to-date data able to assist sub-Saharan African countries formulating appropriate antimalarial drug policies are scarce.Between 9 July 2007 and 19 June 2009, a randomized, non-inferiority (10% difference threshold in efficacy at day 28) clinical trial was carried out at 12 sites in seven sub-Saharan African countries. Each site compared three of four ACTs, namely amodiaquine-artesunate (ASAQ), dihydroartemisinin-piperaquine (DHAPQ), artemether-lumefantrine (AL), or chlorproguanil-dapsone-artesunate (CD+A). Overall, 4,116 children 6-59 mo old with uncomplicated Plasmodium falciparum malaria were treated (1,226 with AL, 1,002 with ASAQ, 413 with CD+A, and 1,475 with DHAPQ), actively followed up until day 28, and then passively followed up for the next 6 mo. At day 28, for the PCR-adjusted efficacy, non-inferiority was established for three pair-wise comparisons: DHAPQ (97.3%) versus AL (95.5%) (odds ratio [OR]: 0.59, 95% CI: 0.37-0.94); DHAPQ (97.6%) versus ASAQ (96.8%) (OR: 0.74, 95% CI: 0.41-1.34), and ASAQ (97.1%) versus AL (94.4%) (OR: 0.50, 95% CI: 0.28-0.92). For the PCR-unadjusted efficacy, AL was significantly less efficacious than DHAPQ (72.7% versus 89.5%) (OR: 0.27, 95% CI: 0.21-0.34) and ASAQ (66.2% versus 80.4%) (OR: 0.40, 95% CI: 0.30-0.53), while DHAPQ (92.2%) had higher efficacy than ASAQ (80.8%) but non-inferiority could not be excluded (OR: 0.35, 95% CI: 0.26-0.48). CD+A was significantly less efficacious than the other three treatments. Day 63 results were similar to those observed at day 28.This large head-to-head comparison of most currently available ACTs in sub-Saharan Africa showed that AL, ASAQ, and DHAPQ had excellent efficacy, up to day 63 post-treatment. The risk of recurrent infections was significantly lower for DHAPQ, followed by ASAQ and then AL, supporting the recent recommendation of considering DHAPQ as a valid option for the treatment of uncomplicated P. falciparum malaria.ClinicalTrials.gov NCT00393679; Pan African Clinical Trials Registry PACTR2009010000911750

Preexposure Intradermal Rabies Vaccination: A Noninferiority Trial in Healthy Adults on Shortening the Vaccination Schedule From 28 to 7 Days

Background The existing 4-week preexposure rabies vaccination schedule is costly and often not practicable. Shorter effective schedules would result in wider acceptance. Methods We conducted a noninferiority trial in 500 healthy adults comparing the safety and immunogenicity of a 2-visit (days 0 and 7) intradermal (ID) primary vaccination (2 doses of 0.1 mL ID of the human diploid cell culture rabies vaccine [HDCV] at days 0 and 7) vs a standard 3-visit schedule (single dose of 0.1 mL ID at days 0, 7, and 28). One year to 3 years after primary vaccination, a single booster dose of 0.1 mL ID of HDCV was given to evaluate the anamnestic rabies antibody response. The primary endpoint for immunogenicity was the percentage of subjects with an adequate antibody level >0.5 IU/mL 7 days after the booster injection. The safety endpoint was the proportion of participants developing adverse reactions following the primary vaccination and/or booster dose. Results All subjects in both study groups possessed a rabies antibody titer >0.5 IU/mL on day 7 following the booster dose. Following the booster dose, subjects exposed to the double-dose 2-visit ID schedule had a geometric mean titer of 37 IU/mL, compared with 25 IU/mL for the single-dose 3-visit schedule (P < .001). Local reactions at the injection site following primary vaccination were mild and transient. Conclusions In healthy adults, ID administration of a double dose of 0.1 mL of HDCV over 2 visits (days 0 and 7) was safe and not inferior to the single-dose 3-visit schedule. Clinical Trials Registration NCT01388985, EudraCT 2011-001612-62.