COVID-19-associated pulmonary aspergillosis in mechanically ventilated patients: a prospective, multicentre UK study

BACKGROUND

Invasive pulmonary aspergillosis is a complication of severe COVID-19, with regional variation in reported incidence and mortality. We describe the incidence, risk factors and mortality associated with COVID-19-associated pulmonary aspergillosis (CAPA) in a prospective, multicentre UK cohort.

METHODS

From March 2020 to March 2021, 266 mechanically ventilated adults with COVID-19 were enrolled across 5 UK hospital intensive care units (ICUs). CAPA was defined using European Confederation for Medical Mycology and the International Society for Human and Animal Mycology criteria and fungal diagnostics performed on respiratory and serum samples.

RESULTS

Twenty-nine of 266 patients (10.9%) had probable CAPA, 14 (5.2%) possible CAPA and none proven CAPA. Probable CAPA was diagnosed a median of 9 (IQR 7-16) days after ICU admission. Factors associated with probable CAPA after multivariable logistic regression were cumulative steroid dose given within 28 days prior to ICU admission (adjusted OR (aOR) 1.16; 95% CI 1.01 to 1.43 per 100 mg prednisolone-equivalent), receipt of an interleukin (IL)-6 inhibitor (aOR 2.79; 95% CI 1.22 to 6.48) and chronic obstructive pulmonary disease (COPD) (aOR 4.78; 95% CI 1.13 to 18.13). Mortality in patients with probable CAPA was 55%, vs 46% in those without. After adjustment for immortal time bias, CAPA was associated with an increased risk of 90-day mortality (HR 1.85; 95% CI 1.07 to 3.19); however, this association did not remain statistically significant after further adjustment for confounders (adjusted HR 1.57; 95% CI 0.88 to 2.80). There was no difference in mortality between patients with CAPA prescribed antifungals (9 of 17; 53%) and those who were not (7 of 12; 58%) (p=0.77).

INTERPRETATION

In this first prospective UK study, probable CAPA was associated with corticosteroid use, receipt of IL-6 inhibitors and pre-existing COPD. CAPA did not impact mortality following adjustment for prognostic variables.

Genetic diversity and microevolution in clinical Cryptococcus isolates from Cameroon

Cryptococcal meningitis is the second most common cause of death in people living with HIV/AIDS, yet we have a limited understanding of how cryptococcal isolates change over the course of infection. Cryptococcal infections are environmentally acquired, and the genetic diversity of these infecting isolates can also be geographically linked. Here, we employ whole genome sequences for 372 clinical Cryptococcus isolates from 341 patients with HIV-associated cryptococcal meningitis obtained via a large clinical trial, across both Malawi and Cameroon, to enable population genetic comparisons of isolates between countries. We see that isolates from Cameroon are highly clonal, when compared to those from Malawi, with differential rates of disruptive variants in genes with roles in DNA binding and energy use. For a subset of patients (22) from Cameroon, we leverage longitudinal sampling, with samples taken at days 7 and 14 post-enrollment, to interrogate the genetic changes that arise over the course of infection, and the genetic diversity of isolates within patients. We see disruptive variants arising over the course of infection in several genes, including the phagocytosis-regulating transcription factor GAT204. In addition, in 13% of patients sampled longitudinally, we see evidence for mixed infections. This approach identifies geographically linked genetic variation, signatures of microevolution, and evidence for mixed infections across a clinical cohort of patients affected by cryptococcal meningitis in Central Africa.

Reduction in mortality from HIV-related CNS infections in routine care in Africa (DREAMM): a before-and-after, implementation study

BACKGROUND

Four decades into the HIV epidemic, CNS infection remains a leading cause of preventable HIV-related deaths in routine care. The Driving Reduced AIDS-associated Meningo-encephalitis Mortality (DREAMM) project aimed to develop, implement, and evaluate pragmatic implementation interventions and strategies to reduce mortality from HIV-related CNS infection.

METHODS

DREAMM took place in five public hospitals in Cameroon, Malawi, and Tanzania. The main intervention was a stepwise algorithm for HIV-related CNS infections including bedside rapid diagnostic testing and implementation of WHO cryptococcal meningitis guidelines. A health system strengthening approach for hospitals was adopted to deliver quality care through a co-designed education programme, optimised clinical and laboratory pathways, and communities of practice. DREAMM was led and driven by local leadership and divided into three phases: observation (including situational analyses of routine care), training, and implementation. Consecutive adults (aged ≥18 years) living with HIV presenting with a first episode of suspected CNS infection were eligible for recruitment. The primary endpoint was the comparison of 2-week all-cause mortality between observation and implementation phases. This study completed follow-up in September, 2021. The project was registered on ClinicalTrials.gov, NCT03226379.

FINDINGS

From November, 2016 to April, 2019, 139 eligible participants were enrolled in the observation phase. From Jan 9, 2018, to March 25, 2021, 362 participants were enrolled into the implementation phase. 216 (76%) of 286 participants had advanced HIV disease (209 participants had missing CD4 cell count), and 340 (69%) of 494 participants had exposure to antiretroviral therapy (ART; one participant had missing ART data). In the implementation phase 269 (76%) of 356 participants had a probable CNS infection, 203 (76%) of whom received a confirmed microbiological or radiological diagnosis of CNS infection using existing diagnostic tests and medicines. 63 (49%) of 129 participants died at 2 weeks in the observation phase compared with 63 (24%) of 266 in the implementation phase; and all-cause mortality was lower in the implementation phase when adjusted for site, sex, age, ART exposure (adjusted risk difference -23%, 95% CI -33 to -13; p<0·001). At 10 weeks, 71 (55%) died in the observation phase compared with 103 (39%) in the implementation phase (-13%, -24 to -3; p=0·01).

INTERPRETATION

DREAMM substantially reduced mortality from HIV-associated CNS infection in resource-limited settings in Africa. DREAMM scale-up is urgently required to reduce deaths in public hospitals and help meet Sustainable Development Goals.

FUNDING

European and Developing Countries Clinical Trials Partnership, French Agency for Research on AIDS and Viral Hepatitis.

TRANSLATIONS

For the French and Portuguese translations of the abstract see Supplementary Materials section.

Cryptococcal Antigenemia in Advanced Human Immunodeficiency Virus Disease: Pathophysiology, Epidemiology, and Clinical Implications

Cryptococcal antigen (CrAg) is detectable in blood prior to the onset of symptomatic cryptococcal meningitis (CM), a leading cause of death among people with advanced human immunodeficiency virus (HIV) disease globally. Highly sensitive assays can detect CrAg in blood, and screening people with HIV with low CD4 counts, followed by preemptive antifungal treatment, is recommended and widely implemented as part of a global strategy to prevent CM and end cryptococcal-related deaths. Cryptococcal antigenemia encompasses a spectrum of conditions from preclinical asymptomatic infection (cerebrospinal fluid [CSF] CrAg-negative) through subclinical (CSF CrAg-positive without overt meningism) to clinical symptomatic cryptococcal disease, usually manifesting as CM. In this review, we summarize current understanding of the pathophysiology, risk factors for, and clinical implications of cryptococcal antigenemia within this spectrum. We also provide an update on global prevalence, recommended screening and treatment strategies, and future considerations for improving outcomes among patients with cryptococcal antigenemia.

Genomic Variation across a Clinical Cryptococcus Population Linked to Disease Outcome

Cryptococcus neoformans is the causative agent of cryptococcosis, a disease with poor patient outcomes that accounts for approximately 180,000 deaths each year. Patient outcomes may be impacted by the underlying genetics of the infecting isolate; however, our current understanding of how genetic diversity contributes to clinical outcomes is limited. Here, we leverage clinical, in vitro growth and genomic data for 284 C. neoformans isolates to identify clinically relevant pathogen variants within a population of clinical isolates from patients with human immunodeficiency virus (HIV)-associated cryptococcosis in Malawi. Through a genome-wide association study (GWAS) approach, we identify variants associated with the fungal burden and the growth rate. We also find both small and large-scale variation, including aneuploidy, associated with alternate growth phenotypes, which may impact the course of infection. Genes impacted by these variants are involved in transcriptional regulation, signal transduction, glycosylation, sugar transport, and glycolysis. We show that growth within the central nervous system (CNS) is reliant upon glycolysis in an animal model and likely impacts patient mortality, as the CNS yeast burden likely modulates patient outcome. Additionally, we find that genes with roles in sugar transport are enriched in regions under selection in specific lineages of this clinical population. Further, we demonstrate that genomic variants in two genes identified by GWAS impact virulence in animal models. Our approach identifies links between the genetic variation in C. neoformans and clinically relevant phenotypes and animal model pathogenesis, thereby shedding light on specific survival mechanisms within the CNS and identifying the pathways involved in yeast persistence. IMPORTANCE Infection outcomes for cryptococcosis, most commonly caused by C. neoformans, are influenced by host immune responses as well as by host and pathogen genetics. Infecting yeast isolates are genetically diverse; however, we lack a deep understanding of how this diversity impacts patient outcomes. To better understand both clinical isolate diversity and how diversity contributes to infection outcomes, we utilize a large collection of clinical C. neoformans samples that were isolated from patients enrolled in a clinical trial across 3 hospitals in Malawi. By combining whole-genome sequence data, clinical data, and in vitro growth data, we utilize genome-wide association approaches to examine the genetic basis of virulence. Genes with significant associations display virulence attributes in both murine and rabbit models, demonstrating that our approach can identify potential links between genetic variants and patho-biologically significant phenotypes.

Cost-effectiveness of single, high-dose, liposomal amphotericin regimen for HIV-associated cryptococcal meningitis in five countries in sub-Saharan Africa: an economic analysis of the AMBITION-cm trial

BACKGROUND

HIV-associated cryptococcal meningitis is a leading cause of AIDS-related mortality. The AMBITION-cm trial showed that a regimen based on a single high dose of liposomal amphotericin B deoxycholate (AmBisome group) was non-inferior to the WHO-recommended treatment of seven daily doses of amphotericin B deoxycholate (control group) and was associated with fewer adverse events. We present a five-country cost-effectiveness analysis.

METHODS

The AMBITION-cm trial enrolled patients with HIV-associated cryptococcal meningitis from eight hospitals in Botswana, Malawi, South Africa, Uganda, and Zimbabwe. Taking a health service perspective, we collected country-specific unit costs and individual resource-use data per participant over the 10-week trial period, calculating mean cost per participant by group, mean cost-difference between groups, and incremental cost-effectiveness ratio per life-year saved. Non-parametric bootstrapping and scenarios analyses were performed including hypothetical real-world resource use. The trial registration number is ISRCTN72509687, and the trial has been completed.

FINDINGS

The AMBITION-cm trial enrolled 844 participants, and 814 were included in the intention-to-treat analysis (327 from Uganda, 225 from Malawi, 107 from South Africa, 84 from Botswana, and 71 from Zimbabwe) with 407 in each group, between Jan 31, 2018, and Feb 17, 2021. Using Malawi as a representative example, mean total costs per participant were US$1369 (95% CI 1314-1424) in the AmBisome group and $1237 (1181-1293) in the control group. The incremental cost-effectiveness ratio was $128 (59-257) per life-year saved. Excluding study protocol-driven cost, using a real-world toxicity monitoring schedule, the cost per life-year saved reduced to $80 (15-275). Changes in the duration of the hospital stay and antifungal medication cost showed the greatest effect in sensitivity analyses. Results were similar across countries, with the cost per life-year saved in the real-world scenario ranging from $71 in Botswana to $121 in Uganda.

INTERPRETATION

The AmBisome regimen was cost-effective at a low incremental cost-effectiveness ratio. The regimen might be even less costly and potentially cost-saving in real-world implementation given the lower drug-related toxicity and the potential for shorter hospital stays.

FUNDING

European Developing Countries Clinical Trials Partnership, Swedish International Development Cooperation Agency, Wellcome Trust and Medical Research Council, UKAID Joint Global Health Trials, and the National Institute for Health Research.

TRANSLATIONS

For the Chichewa, Isixhosa, Luganda, Setswana and Shona translations of the abstract see Supplementary Materials section.

Implementation of WHO guidelines on management of advanced HIV disease and its impact among TB co-infected patients in Tanzania: a retrospective follow-up study

BACKGROUND

The commonest causes of mortality in people living with HIV (PLHIV) are preventable and the majority can be attributed to undiagnosed tuberculosis (TB). National HIV/AIDS control programs are encouraged to implement the WHO package of interventions to improve survival among PLHIV. We assessed the implementation of the WHO TB-related package of care for Advanced HIV Disease (AHD) and its impact on treatment outcomes among HIV/TB patients in Tanzania.

METHODS

A retrospective cohort study was employed among HIV/AIDS patients on antiretroviral therapy from 21 public health facilities in three regions (Dar es Salaam, Coastal, and Morogoro) of Tanzania. Patients enrolled in care between January 2013- June 2017 (before the introduction of the WHO guidelines) and July 2017-Sept 2018 (during the implementation of the guidelines) were recruited. Data abstraction was done from patient hospital files using a structured questionnaire uploaded on a tablet.

RESULTS

Data from 2624 patients records were collected. Overall, 50% of patients with HIV had AHD with 7.8% of these co-infected with TB. Among AHD participants, 58.3% were female, 80.7% were from urban areas and 40.0% visited care and treatment centres as self-referrals. Implementation of the WHO AHD package of care was very low, ranging from 0% for Urine LF-LAM test done among patients with symptoms and signs of TB to 39.7% AHD concurrent with TB patients whose ART initiation was deferred for 2 weeks. Overall, the Proportion of AHD patients diagnosed with TB was 4.8%, Of which sputum Xpert as the first test for TB diagnosis was 4.4%. Five patients (0.6%) were documented to have received IPT at enrolment. Tailored counselling to ensure optimal adherence to ART for viral suppression was given to 12.1%. AHD patients co-infected with TB were retained in care more before the introduction of WHO AHD guideline (82.1%) compared to the period after the introduction of the guideline (53.9%) (p = 0.008). Clinical failure at 6 months among AHD patients was 10.6% before the guideline and 11.4% after the guideline. Immunological failure was observed in 1 patient (9.1%) before the guideline and 1 patient (7.1%) after the guideline. After the introduction of the guideline, mortality was 5.9% and no mortality was observed before the guideline. All the differences were not statistically significant.

CONCLUSIONS

Implementation of the TB related WHO packages of care for AHD is very low. Except for TB diagnosis, other parameters did not improve with the introduction of the guidelines. More research is recommended to ascertain the effectiveness of guidelines as well as an understanding of the mechanisms involved.

Single-Dose Liposomal Amphotericin B Treatment for Cryptococcal Meningitis

BACKGROUND

Cryptococcal meningitis is a leading cause of human immunodeficiency virus (HIV)-related death in sub-Saharan Africa. Whether a treatment regimen that includes a single high dose of liposomal amphotericin B would be efficacious is not known.

METHODS

In this phase 3 randomized, controlled, noninferiority trial conducted in five African countries, we assigned HIV-positive adults with cryptococcal meningitis in a 1:1 ratio to receive either a single high dose of liposomal amphotericin B (10 mg per kilogram of body weight) on day 1 plus 14 days of flucytosine (100 mg per kilogram per day) and fluconazole (1200 mg per day) or the current World Health Organization-recommended treatment, which includes amphotericin B deoxycholate (1 mg per kilogram per day) plus flucytosine (100 mg per kilogram per day) for 7 days, followed by fluconazole (1200 mg per day) for 7 days (control). The primary end point was death from any cause at 10 weeks; the trial was powered to show noninferiority at a 10-percentage-point margin.

RESULTS

A total of 844 participants underwent randomization; 814 were included in the intention-to-treat population. At 10 weeks, deaths were reported in 101 participants (24.8%; 95% confidence interval [CI], 20.7 to 29.3) in the liposomal amphotericin B group and 117 (28.7%; 95% CI, 24.4 to 33.4) in the control group (difference, -3.9 percentage points); the upper boundary of the one-sided 95% confidence interval was 1.2 percentage points (within the noninferiority margin; P<0.001 for noninferiority). Fungal clearance from cerebrospinal fluid was -0.40 log10 colony-forming units (CFU) per milliliter per day in the liposomal amphotericin B group and -0.42 log10 CFU per milliliter per day in the control group. Fewer participants had grade 3 or 4 adverse events in the liposomal amphotericin B group than in the control group (50.0% vs. 62.3%).

CONCLUSIONS

Single-dose liposomal amphotericin B combined with flucytosine and fluconazole was noninferior to the WHO-recommended treatment for HIV-associated cryptococcal meningitis and was associated with fewer adverse events. (Funded by the European and Developing Countries Clinical Trials Partnership and others; Ambition ISRCTN number, ISRCTN72509687.).

Combination Therapy for HIV-Associated Cryptococcal Meningitis-A Success Story

Cryptococcal meningitis is the leading cause of adult meningitis in patients with HIV, and accounts for 15% of all HIV-related deaths in sub-Saharan Africa. The mainstay of management is effective antifungal therapy, despite a limited arsenal of antifungal drugs, significant progress has been made developing effective treatment strategies by using combination regimens. The introduction of fluconazole as a safe and effective step-down therapy allowed for shorter courses of more fungicidal agents to be given as induction therapy, with higher doses achieving more rapid CSF sterilisation and improved treatment outcomes. The development of early fungicidal activity (EFA), an easily measured surrogate of treatment efficacy, has enabled rapid identification of effective combinations through dose ranging phase II studies, allowing further evaluation of clinical benefit in targeted phase III studies. Recent clinical trials have shown that shorter course induction regimens using one week of amphotericin paired with flucytosine are non-inferior to traditional two-week induction regimens and that the combination of fluconazole and flucytosine offers a viable treatment alternative when amphotericin is unavailable. Access to drugs in many low and middle-income settings remains challenging but is improving, and novel strategies based on single high dose liposomal amphotericin B promise further reduction in treatment complications and toxicities. This review aims to summarise the key findings of the principal clinical trials that have led to the success story of combination therapy thus far.

Multiplicity adjustments in parallel-group multi-arm trials sharing a control group: Clear guidance is needed

Multi-arm, parallel-group clinical trials are an efficient way of testing several new treatments, treatment regimens or doses. However, guidance on the requirement for statistical adjustment to control for multiple comparisons (type I error) using a shared control group is unclear. We argue, based on current evidence, that adjustment is not always necessary in such situations. We propose that adjustment should not be a requirement in multi-arm, parallel-group trials testing distinct treatments and sharing a control group, and we call for clearer guidance from stakeholders, such as regulators and scientific journals, on the appropriate settings for adjustment of multiplicity.

Short-term Mortality Outcomes of HIV-Associated Cryptococcal Meningitis in Antiretroviral Therapy-Naïve and -Experienced Patients in Sub-Saharan Africa

BACKGROUND

An increasing proportion of patients with HIV-associated cryptococcal meningitis have received antiretroviral therapy (ART) before presentation. There is some evidence suggesting an increased 2-week mortality in those receiving ART for <14 days compared with those on ART for >14 days. However, presentation and outcomes for cryptococcal meningitis patients who have recently initiated ART, and those with virologic failure and/or nonadherence, are not well described.

METHODS

Six hundred seventy-eight adults with a first episode of cryptococcal meningitis recruited into a randomized, noninferiority, multicenter phase 3 trial in 4 Sub-Saharan countries were analyzed to compare clinical presentation and 2- and 10-week mortality outcomes between ART-naïve and -experienced patients and between patients receiving ART for varying durations before presentation.

RESULTS

Over half (56%; 381/678) the study participants diagnosed with a first episode of cryptococcal meningitis were ART-experienced. All-cause mortality was similar at 2 weeks (17% vs 20%; hazard ratio [HR], 0.85; 95% CI, 0.6-1.2; P = .35) and 10 weeks (38% vs 36%; HR, 1.03; 95% CI, 0.8-1.32; P = .82) for ART-experienced and ART-naïve patients. Among ART-experienced patients, using different cutoff points for ART duration, there were no significant differences in 2- and 10-week mortality based on duration of ART.

CONCLUSIONS

In this study, there were no significant differences in mortality at 2 and 10 weeks between ART-naïve and -experienced patients and between ART-experienced patients according to duration on ART.

Fungal Burden and Raised Intracranial Pressure Are Independently Associated With Visual Loss in Human Immunodeficiency Virus-Associated Cryptococcal Meningitis

Among 472 patients with human immunodeficiency virus-associated cryptococcal meningitis, 16% had severe visual loss at presentation, and 46% of these were 4-week survivors and remained severely impaired. Baseline cerebrospinal fluid opening pressure ≥40 cmH₂O (adjusted odds ratio [aOR], 2.56; 95% confidence interval [CI], 1.36-4.83; P = .02) and fungal burden >6.0 log₁₀ colonies/mL (aOR, 3.01; 95% CI, 1.58-5.7; P = .003) were independently associated with severe visual loss.

Co-prevalent infections in adults with HIV-associated cryptococcal meningitis are associated with an increased risk of death: a nested analysis of the Advancing Cryptococcal meningitis Treatment for Africa (ACTA) cohort

Background: HIV-associated cryptococcal meningitis accounts for 15% of AIDS related deaths globally. In sub-Saharan Africa, acute mortality ranges from 24% to 100%. In addition to the mortality directly associated with cryptococcosis, patients with HIV-associated cryptococcal meningitis are at risk of a range of opportunistic infections (OIs) and hospital acquired nosocomial infections (HAIs). The attributable mortality associated with co-prevalent infections in cryptococcal meningitis has not been evaluated. Methods: As part of the Advancing Cryptococcal meningitis Treatment for Africa (ACTA) trial, consecutive HIV-positive adults with cryptococcal meningitis were randomised to one of five anti-fungal regimens and followed up until 10-weeks. We conducted a retrospective case note review of ACTA participants recruited from Queen Elizabeth Central Hospital in Blantyre, Malawi to describe the range and prevalence of OIs and HAIs diagnosed, and the attributable mortality associated with these infections. Results: We describe the prevalence of OIs and HAIs in 226 participants. Baseline median CD4 count was 29 cell/mm3, 57% (129/226) were on anti-retroviral therapy. 56% (127/226) had at least one co-prevalent infection during the 10-week study period. Data were collected for 187 co-prevalent infection episodes. Suspected blood stream infection was the commonest co-prevalent infection diagnosed (34/187, 18%), followed by community-acquired pneumonia (32/187, 17%), hospital-acquired pneumonia (13/187, 7%), pulmonary tuberculosis (12/187, 6%) and confirmed blood stream infections (10/187, 5%). All-cause mortality at 10-weeks was 35% (80/226), diagnosis of an OI or HAI increased the risk of death at 10 weeks by nearly 50% (HR 1.48, 95% CI 1.01-2.17, p=0.04). Conclusion: We demonstrate the high prevalence and broad range of OIs and HAIs occurring in patients with HIV-associated cryptococcal meningitis. These co-prevalent infections are associated with a significantly increased risk of death. Whether a protocolised approach to improve surveillance and proactive treatment of co-prevalent infections would improve cryptococcal meningitis outcomes warrants further investigation.

One-year Mortality Outcomes From the Advancing Cryptococcal Meningitis Treatment for Africa Trial of Cryptococcal Meningitis Treatment in Malawi

In Malawi, 236 participants from the Advancing Cryptococcal Meningitis Treatment for Africa trial were followed for 12 months. The trial outcomes reported at 10 weeks were sustained to 1 year. One-week amphotericin B plus flucytosine was associated with the lowest 1 year mortality (27.5% [95% confidence interval, 16.3 to 44.1]).

Addition of Flucytosine to Fluconazole for the Treatment of Cryptococcal Meningitis in Africa: A Multicountry Cost-effectiveness Analysis

BACKGROUND

Mortality from cryptococcal meningitis remains very high in Africa. In the Advancing Cryptococcal Meningitis Treatment for Africa (ACTA) trial, 2 weeks of fluconazole (FLU) plus flucytosine (5FC) was as effective and less costly than 2 weeks of amphotericin-based regimens. However, many African settings treat with FLU monotherapy, and the cost-effectiveness of adding 5FC to FLU is uncertain.

METHODS

The effectiveness and costs of FLU+5FC were taken from ACTA, which included a costing analysis at the Zambian site. The effectiveness of FLU was derived from cohorts of consecutively enrolled patients, managed in respects other than drug therapy, as were participants in ACTA. FLU costs were derived from costs of FLU+5FC in ACTA, by subtracting 5FC drug and monitoring costs. The cost-effectiveness of FLU+5FC vs FLU alone was measured as the incremental cost-effectiveness ratio (ICER). A probabilistic sensitivity analysis assessed uncertainties and a bivariate deterministic sensitivity analysis examined the impact of varying mortality and 5FC drug costs on the ICER.

RESULTS

The mean costs per patient were US $847 (95% confidence interval [CI] $776-927) for FLU+5FC, and US $628 (95% CI $557-709) for FLU. The 10-week mortality rate was 35.1% (95% CI 28.9-41.7%) with FLU+5FC and 53.8% (95% CI 43.1-64.1%) with FLU. At the current 5FC price of US $1.30 per 500 mg tablet, the ICER of 5FC+FLU versus FLU alone was US $65 (95% CI $28-208) per life-year saved. Reducing the 5FC cost to between US $0.80 and US $0.40 per 500 mg resulted in an ICER between US $44 and US $28 per life-year saved.

CONCLUSIONS

The addition of 5FC to FLU is cost-effective for cryptococcal meningitis treatment in Africa and, if made available widely, could substantially reduce mortality rates among human immunodeficiency virus-infected persons in Africa.

Healthcare Costs and Life-years Gained From Treatments Within the Advancing Cryptococcal Meningitis Treatment for Africa (ACTA) Trial on Cryptococcal Meningitis: A Comparison of Antifungal Induction Strategies in Sub-Saharan Africa

Background

Mortality from cryptoccocal meningitis remains high. The ACTA trial demonstrated that, compared with 2 weeks of amphotericin B (AmB) plus flucystosine (5FC), 1 week of AmB and 5FC was associated with lower mortality and 2 weeks of oral flucanozole (FLU) plus 5FC was non-inferior. Here, we assess the cost-effectiveness of these different treatment courses.

Methods

Participants were randomized in a ratio of 2:1:1:1:1 to 2 weeks of oral 5FC and FLU, 1 week of AmB and FLU, 1 week of AmB and 5FC, 2 weeks of AmB and FLU, or 2 weeks of AmB and 5FC in Malawi, Zambia, Cameroon, and Tanzania. Data on individual resource use and health outcomes were collected. Cost-effectiveness was measured as incremental costs per life-year saved, and non-parametric bootstrapping was done.

Results

Total costs per patient were US $1442 for 2 weeks of oral FLU and 5FC, $1763 for 1 week of AmB and FLU, $1861 for 1 week of AmB and 5FC, $2125 for 2 weeks of AmB and FLU, and $2285 for 2 weeks of AmB and 5FC. Compared to 2 weeks of AmB and 5FC, 1 week of AmB and 5FC was less costly and more effective and 2 weeks of oral FLU and 5FC was less costly and as effective. The incremental cost-effectiveness ratio for 1 week of AmB and 5FC versus oral FLU and 5FC was US $208 (95% confidence interval $91–1210) per life-year saved.

Clinical Trials Registration

ISRCTN45035509.

Conclusions

Both 1 week of AmB and 5FC and 2 weeks of Oral FLU and 5FC are cost-effective treatments.

Long-term Mortality and Disability in Cryptococcal Meningitis: A Systematic Literature Review

Cryptococcal meningitis (CM) is the primary cause of meningitis in adults with human immunodeficiency virus (HIV) infection and an emerging disease in HIV-seronegative individuals. No literature review has studied the long-term outcome of CM. We performed a systematic review on the long-term (≥3-month) impact of CM (Cryptococcus neoformans and Cryptococcus gattii) on mortality and disability in HIV-infected and non-HIV-infected adults. Although the quality of current evidence is limited, the long-term impact of CM on survival and disability seems to be high. One-year mortality ranged from 13% in an Australian non-HIV-infected C. gattii-infected cohort to 78% in a Malawian HIV-infected cohort treated with fluconazole monotherapy. One-year impairment proportions among survivors ranged from 19% in an Australian C. gattii cohort to >70% in a Taiwanese non-HIV- and HIV-infected cohorts. Ongoing early therapeutic interventions, early detection of impairments and access to rehabilitation services may significantly improve patients' survival and quality of life.

Leave no one behind: response to new evidence and guidelines for the management of cryptococcal meningitis in low-income and middle-income countries

In 2018, WHO issued guidelines for the diagnosis, prevention, and management of HIV-related cryptococcal disease. Two strategies are recommended to reduce the high mortality associated with HIV-related cryptococcal meningitis in low-income and middle-income countries (LMICs): optimised combination therapies for confirmed meningitis cases and cryptococcal antigen screening programmes for ambulatory people living with HIV who access care. WHO's preferred therapy for the treatment of HIV-related cryptococcal meningitis in LMICs is 1 week of amphotericin B plus flucytosine, and the alternative therapy is 2 weeks of fluconazole plus flucytosine. In the ACTA trial, 1-week (short course) amphotericin B plus flucytosine resulted in a 10-week mortality of 24% (95% CI -16 to 32) and 2 weeks of fluconazole and flucytosine resulted in a 10-week mortality of 35% (95% CI -29 to 41). However, with widely used fluconazole monotherapy, mortality because of HIV-related cryptococcal meningitis is approximately 70% in many African LMIC settings. Therefore, the potential to transform the management of HIV-related cryptococcal meningitis in resource-limited settings is substantial. Sustainable access to essential medicines, including flucytosine and amphotericin B, in LMICs is paramount and the focus of this Personal View.

Dynamic ploidy changes drive fluconazole resistance in human cryptococcal meningitis

BACKGROUND

Cryptococcal meningitis (CM) causes an estimated 180,000 deaths annually, predominantly in sub-Saharan Africa, where most patients receive fluconazole (FLC) monotherapy. While relapse after FLC monotherapy with resistant strains is frequently observed, the mechanisms and impact of emergence of FLC resistance in human CM are poorly understood. Heteroresistance (HetR) - a resistant subpopulation within a susceptible strain - is a recently described phenomenon in Cryptococcus neoformans (Cn) and Cryptococcus gattii (Cg), the significance of which has not previously been studied in humans.

METHODS

A cohort of 20 patients with HIV-associated CM in Tanzania was prospectively observed during therapy with either FLC monotherapy or in combination with flucytosine (5FC). Total and resistant subpopulations of Cryptococcus spp. were quantified directly from patient cerebrospinal fluid (CSF). Stored isolates underwent whole genome sequencing and phenotypic characterization.

RESULTS

Heteroresistance was detectable in Cryptococcus spp. in the CSF of all patients at baseline (i.e., prior to initiation of therapy). During FLC monotherapy, the proportion of resistant colonies in the CSF increased during the first 2 weeks of treatment. In contrast, no resistant subpopulation was detectable in CSF by day 14 in those receiving a combination of FLC and 5FC. Genomic analysis revealed high rates of aneuploidy in heteroresistant colonies as well as in relapse isolates, with chromosome 1 (Chr1) disomy predominating. This is apparently due to the presence on Chr1 of ERG11, which is the FLC drug target, and AFR1, which encodes a drug efflux pump. In vitro efflux levels positively correlated with the level of heteroresistance.

CONCLUSION

Our findings demonstrate for what we believe is the first time the presence and emergence of aneuploidy-driven FLC heteroresistance in human CM, association of efflux levels with heteroresistance, and the successful suppression of heteroresistance with 5FC/FLC combination therapy.

FUNDING

This work was supported by the Wellcome Trust Strategic Award for Medical Mycology and Fungal Immunology 097377/Z/11/Z and the Daniel Turnberg Travel Fellowship.

Short-course High-dose Liposomal Amphotericin B for Human Immunodeficiency Virus-associated Cryptococcal Meningitis: A Phase 2 Randomized Controlled Trial

Background

We performed a phase 2 noninferiority trial examining the early fungicidal activity (EFA) of 3 short-course, high-dose liposomal amphotericin B (L-AmB) regimens for cryptococcal meningitis (CM) in Tanzania and Botswana.

Methods

Human immunodeficiency virus (HIV)-infected adults with CM were randomized to (i) L-AmB 10 mg/kg on day 1 (single dose); (ii) L-AmB 10 mg/kg on day 1 and 5 mg/kg on day 3 (2 doses); (iii) L-AmB 10 mg/kg on day 1 and 5 mg/kg on days 3 and 7 (3 doses); or (iv) L-AmB 3 mg/kg/day for 14 days (control). All patients also received oral fluconazole 1200 mg/day for 14 days. Primary endpoint was mean rate of clearance of cerebrospinal fluid cryptococcal infection (EFA). Noninferiority was defined as an upper limit of the 2-sided 95% confidence interval (CI) of difference in EFA between intervention and control <0.2 log10 colony-forming units (CFU)/mL/day.

Results

Eighty participants were enrolled. EFA for daily L-AmB was -0.41 log10 CFU/mL/day (standard deviation, 0.11; n = 17). Difference in mean EFA from control was -0.11 (95% CI, -.29 to .07) log10 CFU/mL/day faster with single dose (n = 16); -0.05 (95% CI, -.20 to .10) log10 CFU/mL/day faster with 2 doses (n = 18); and -0.13 (95% CI, -.35 to .09) log10 CFU/mL/day faster with 3 doses (n = 18). EFA in all short-course arms was noninferior to control. Ten-week mortality was 29% (n = 23) with no statistical difference between arms. All arms were well tolerated.

Conclusions

Single-dose 10 mg/kg L-AmB was well tolerated and led to noninferior EFA compared to 14 days of 3 mg/kg/day L-AmB in HIV-associated CM. Induction based on a single 10 mg/kg L-AmB dose is being taken forward to a phase 3 clinical endpoint trial.

Clinical Trials Registration

ISRCTN 10248064.

Effect of oral fluconazole 1200 mg/day on QT interval in African adults with HIV-associated cryptococcal meningitis

: We assessed the effect of fluconazole 1200 mg/day on the QT interval in cryptococcal meningitis patients. Mean corrected QT (QTc) change from baseline to day 7 was 10.1 ms (IQR: -28 to 46 ms) in the fluconazole treatment group and -12.6 ms (IQR: -39 to 13.5 ms) in those not taking fluconazole (P = 0.04). No significant increase in QTc measurements over 500 ms was observed with fluconazole. Nevertheless, it remains important to correct any electrolyte imbalance and avoid concomitant drugs that may increase QTc.

Antifungal Combinations for Treatment of Cryptococcal Meningitis in Africa

BACKGROUND

Cryptococcal meningitis accounts for more than 100,000 human immunodeficiency virus (HIV)-related deaths per year. We tested two treatment strategies that could be more sustainable in Africa than the standard of 2 weeks of amphotericin B plus flucytosine and more effective than the widely used fluconazole monotherapy.

METHODS

We randomly assigned HIV-infected adults with cryptococcal meningitis to receive an oral regimen (fluconazole [1200 mg per day] plus flucytosine [100 mg per kilogram of body weight per day] for 2 weeks), 1 week of amphotericin B (1 mg per kilogram per day), or 2 weeks of amphotericin B (1 mg per kilogram per day). Each patient assigned to receive amphotericin B was also randomly assigned to receive fluconazole or flucytosine as a partner drug. After induction treatment, all the patients received fluconazole consolidation therapy and were followed to 10 weeks.

RESULTS

A total of 721 patients underwent randomization. Mortality in the oral-regimen, 1-week amphotericin B, and 2-week amphotericin B groups was 18.2% (41 of 225), 21.9% (49 of 224), and 21.4% (49 of 229), respectively, at 2 weeks and was 35.1% (79 of 225), 36.2% (81 of 224), and 39.7% (91 of 229), respectively, at 10 weeks. The upper limit of the one-sided 97.5% confidence interval for the difference in 2-week mortality was 4.2 percentage points for the oral-regimen group versus the 2-week amphotericin B groups and 8.1 percentage points for the 1-week amphotericin B groups versus the 2-week amphotericin B groups, both of which were below the predefined 10-percentage-point noninferiority margin. As a partner drug with amphotericin B, flucytosine was superior to fluconazole (71 deaths [31.1%] vs. 101 deaths [45.0%]; hazard ratio for death at 10 weeks, 0.62; 95% confidence interval [CI], 0.45 to 0.84; P=0.002). One week of amphotericin B plus flucytosine was associated with the lowest 10-week mortality (24.2%; 95% CI, 16.2 to 32.1). Side effects, such as severe anemia, were more frequent with 2 weeks than with 1 week of amphotericin B or with the oral regimen.

CONCLUSIONS

One week of amphotericin B plus flucytosine and 2 weeks of fluconazole plus flucytosine were effective as induction therapy for cryptococcal meningitis in resource-limited settings. (ACTA Current Controlled Trials number, ISRCTN45035509 .).

Cryptococcal Antigen Screening in Asymptomatic HIV-Infected Antiretroviral Naïve Patients in Cameroon and Evaluation of the New Semi-Quantitative Biosynex CryptoPS Test

Background: Cryptococcal meningitis (CM) is a major cause of AIDS-related mortality in Africa. Detection of serum cryptococcal antigen (CrAg) predicts development of CM in antiretroviral (ART) naïve HIV-infected patients with severe immune depression. Systematic pre-ART CrAg screening and pre-emptive oral fluconazole is thus recommended. We postulated that a semi-quantitative CrAg screening approach could offer clinically relevant advantages.

Methods: ART-naïve asymptomatic adult outpatients with <100 CD₄ cells/mm³ presenting to the Yaoundé Central Hospital, Cameroon were screened for CrAg using the IMMY lateral flow assay (LFA). CrAg positive patients were consented for lumbar puncture and those with proven CM were treated with combination antifungal therapy and those with no CM were offered long-term oral fluconazole. Simultaneous on-site evaluation of CrAg detection using the new LFA Biosynex^® CryptoPS test was performed and both tests were subsequently compared to a reference commercialized CrAg enzyme immunoassay (EIA).

Results: Prevalence of serum CrAg in 186 screened adults was 7.5% (95%CI: 4.5–12.4). In CrAg positive patients, CM prevalence was 45.5% (95%CI: 18.3–75.7). IMMY and Biosynex CryptoPS strongly agreed in serum, plasma, and cerebrospinal fluid (Kappa: 98.4, 99.5, 100%, respectively, p < 0.001), and disagreed in urine (29 isolated positive CrAg in urine with IMMY, none with Biosynex and none of whom had proven CM). Compared to EIA, serum specificities were 96.6 and 98.3%, respectively. With Biosynex CryptoPS, all CM patients were serum T2-band positive compared to nonewithout CM. Median EIA reciprocal titre was 160 (IQR: 13.5–718.8) and titres >160 strongly correlated with proven CM and Biosynex CryptoPS T2-band positivity. During the 1-year follow up period, there was no incident case of CM among screened patients and overall incidence of all-cause mortality was 31.5 per 100 person-years-at-risk (95%CI: 23.0–43.1).

Conclusion: HIV-associated asymptomatic cryptococcosis is common in Cameroon, warranting integrated systematic screening and treatment. Biosynex CryptoPS holds promise, at point of care, for rapidly stratifying CrAg positive patients for optimal management including lumbar puncture and combination antifungal therapy when needed.

Summary findings: Prevalence of CrAg and meningitis (CM) is high in Cameroon. Biosynex CryptoPS is comparable to IMMY LFA in CrAg screening. Its T2-band correlates with high antigen titres and CM, thus promising for identifying patients requiring effective induction therapy.

Note: This study was presented in part at the 10th International Conference on Cryptococcus and Cryptococcosis (ICCC) in Iguazu in Brazil from 26 to 30^th March 2017 and won a prize oral presentation.

Characterisation of the opposing effects of G6PD deficiency on cerebral malaria and severe malarial anaemia

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is believed to confer protection against Plasmodium falciparum malaria, but the precise nature of the protective effecthas proved difficult to define as G6PD deficiency has multiple allelic variants with different effects in males and females, and it has heterogeneous effects on the clinical outcome of P. falciparum infection. Here we report an analysis of multiple allelic forms of G6PD deficiency in a large multi-centre case-control study of severe malaria, using the WHO classification of G6PD mutations to estimate each individual's level of enzyme activity from their genotype. Aggregated across all genotypes, we find that increasing levels of G6PD deficiency are associated with decreasing risk of cerebral malaria, but with increased risk of severe malarial anaemia. Models of balancing selection based on these findings indicate that an evolutionary trade-off between different clinical outcomes of P. falciparum infection could have been a major cause of the high levels of G6PD polymorphism seen in human populations.

Monitoring clinical trials: a practical guide

This article describes the processes and procedures involved in planning, conducting and reporting monitoring activities for large Clinical Trials of Investigational Medicinal Products (CTIMPs), focusing on those conducted in resource-limited settings.

AMBITION-cm: intermittent high dose AmBisome on a high dose fluconazole backbone for cryptococcal meningitis induction therapy in sub-Saharan Africa: study protocol for a randomized controlled trial

BACKGROUND

Cryptococcal meningitis (CM) is a leading cause of mortality among HIV-infected individuals in Africa. Poor outcomes from conventional antifungal therapies, unavailability of flucytosine, and difficulties administering 14 days of amphotericin B are key drivers of this mortality. Novel treatment regimes are needed. This study examines whether short-course high-dose liposomal amphotericin B (AmBisome), given with high dose fluconazole, is non-inferior (in terms of microbiological and clinical endpoints) to standard-dose 14-day courses of AmBisome plus high dose fluconazole for treatment of HIV-associated CM.

METHODOLOGY/DESIGN

This is an adaptive open-label phase II/III randomised non-inferiority trial comparing alternative short course AmBisome regimens. Step 1 (phase II) will compare four treatment arms in 160 adult patients (≥ 18 years old) with a first episode of HIV-associated CM, using early fungicidal activity (EFA) as the primary outcome: 1) AmBisome 10 mg/kg day one (single dose); 2) AmBisome 10 mg/kg day one and AmBisome 5 mg/kg day three (two doses); 3) AmBisome 10 mg/kg day one, and AmBisome 5 mg/kg days three and seven (three doses); and 4) AmBisome 3 mg/kg/d for 14 days (control); all given with fluconazole 1200 mg daily for 14 days. STEP 2 (phase III) will enrol 300 participants and compare two treatment arms using all-cause mortality within 70 days as the primary outcome: 1) the shortest course AmBisome regimen found to be non-inferior in terms of EFA to the 14-day control arm in STEP 1, and 2) AmBisome 3 mg/kg/d for 14 days (control), both given with fluconazole 1200 mg daily for 14 days. STEP 2 analysis will include all patients from STEP 1 and STEP 2 taking the STEP 2 regimens. All patients will be followed for ten weeks, and mortality and safety data recorded. All patients will receive consolidation therapy with fluconazole 400-800 mg daily and ART in accordance with local guidelines. The primary analysis (for both STEP 1 and STEP 2) will be intention-to-treat.

TRIAL REGISTRATION

ISRCTN10248064. Date of Registration: 22 January 2014.

Neurological, visual, and MRI brain scan findings in 87 South African patients with HIV-associated cryptococcal meningoencephalitis

BACKGROUND

HIV-associated cryptococcal meningoencephalitis (CM) is a leading cause of adult meningitis in sub-Saharan Africa. Neuroradiological data is however limited to case reports and small case series from developed countries and/or immunocompetent patients.

METHODS

Eighty seven patients aged ≥18 hospitalized with a first episode of CM had magnetic resonance (MRI) imaging during the first two weeks of admission. A subset of eleven patients had follow-up scans approximately one month from their initial MRI scan. All had prospectively-recorded detailed neurological and visual examinations.

RESULTS

An abnormal finding on neurological examination was detected in 33 (39%) patients. 38 (48%) patients experienced some visual loss. Neuroradiological lesions presumed to be cryptococcosis-related, as defined by the presence of dilated Virchow Robin spaces, pseudocysts or cryptococcomas, enhancing nodules, hydrocephalus, meningitis, focal perilesional oedema and infarcts, were detected in 55 (63%) patients. MRI findings suggestive of a second diagnosis were found in 18 (21%) patients. Visual loss was associated with the presence of cryptococcal-related lesions (p = 0.02). Blindness was associated with raised intracranial pressure (ICP) (p = 0.02). Of eleven patients with paired scans, brain swelling was identified on the initial scan in only one patient.

CONCLUSION

The majority of patients had MRI brain scan abnormalities presumed secondary to CM. Dilated Virchow Robin spaces were the commonest neuroradiological lesion. Visual loss was associated with the degree of cerebral involvement as reflected by the presence of MRI abnormalities. Blindness was associated with the presence of raised ICP. Initial generalised brain swelling does not appear to be common, but further studies with paired scans are needed.

Plasma cytokines, chemokines and cellular immune responses in pre-school Nigerian children infected with Plasmodium falciparum

BACKGROUND

Malaria is a major cause of morbidity and mortality worldwide with over one million deaths annually, particularly in children under five years. This study was the first to examine plasma cytokines, chemokines and cellular immune responses in pre-school Nigerian children infected with Plasmodium falciparum from four semi-urban villages near Ile-Ife, Osun State, Nigeria.

METHODS

Blood was obtained from 231 children (aged 39-73 months) who were classified according to mean P. falciparum density per μl of blood (uninfected (n = 89), low density (<1,000, n = 51), medium density (1,000-10,000, n = 65) and high density (>10,000, n = 22)). IL-12p70, IL-10, Nitric oxide, IFN-γ, TNF, IL-17, IL-4 and TGF-β, C-C chemokine RANTES, MMP-8 and TIMP-1 were measured in plasma. Peripheral blood mononuclear cells were obtained and examined markers of innate immune cells (CD14, CD36, CD56, CD54, CD11c AND HLA-DR). T-cell sub-populations (CD4, CD3 and γδTCR) were intracellularly stained for IL-10, IFN-γ and TNF following polyclonal stimulation or stimulated with malaria parasites. Ascaris lumbricoides was endemic in these villages and all data were analysed taking into account the potential impact of bystander helminth infection. All data were analysed using SPSS 15 for windows and in all tests, p <0.05 was deemed significant.

RESULTS

The level of P. falciparum parasitaemia was positively associated with plasma IL-10 and negatively associated with IL-12p70. The percentage of monocytes was significantly decreased in malaria-infected individuals while malaria parasitaemia was positively associated with increasing percentages of CD54+, CD11c+ and CD56+ cell populations. No association was observed in cytokine expression in mitogen-activated T-cell populations between groups and no malaria specific immune responses were detected. Although A. lumbricoides is endemic in these villages, an analysis of the data showed no impact of this helminth infection on P. falciparum parasitaemia or on immune responses associated with P. falciparum infection.

CONCLUSIONS

These findings indicate that Nigerian children infected with P. falciparum exhibit immune responses associated with active malaria infection and these responses were positively associated with increased P. falciparum parasitaemia.

Ascaris co-infection does not alter malaria-induced anaemia in a cohort of Nigerian preschool children

BACKGROUND

Co-infection with malaria and intestinal parasites such as Ascaris lumbricoides is common. Malaria parasites induce a pro-inflammatory immune response that contributes to the pathogenic sequelae, such as malarial anaemia, that occur in malaria infection. Ascaris is known to create an anti-inflammatory immune environment which could, in theory, counteract the anti-malarial inflammatory immune response, minimizing the severity of malarial anaemia. This study examined whether Ascaris co-infection can minimize the severity of malarial anaemia.

METHODS

Data from a randomized controlled trial on the effect of antihelminthic treatment in Nigerian preschool-aged (6-59 months) children conducted in 2006-2007 were analysed to examine the effect of malaria and Ascaris co-infection on anaemia severity. Children were enrolled and tested for malaria, helminths and anaemia at baseline, four, and eight months. Six hundred and ninety subjects were analysed in this study. Generalized linear mixed models were used to assess the relationship between infection status and Ascaris and Plasmodium parasite intensity on severity of anaemia, defined as a haemoglobin less than 11 g/dL.

RESULTS

Malaria prevalence ranged from 35-78% over the course of this study. Of the malaria-infected children, 55% were co-infected with Ascaris at baseline, 60% were co-infected four months later and 48% were co-infected eight months later, underlining the persistent prevalence of malaria-nematode co-infections in this population. Over the course of the study the percentage of anaemic subjects in the population ranged between 84% at baseline and 77% at the eight-month time point. The odds of being anaemic were four to five times higher in children infected with malaria compared to those without malaria. Ascaris infection alone did not increase the odds of being anaemic, indicating that malaria was the main cause of anaemia in this population. There was no significant difference in the severity of anaemia between children singly infected with malaria and co-infected with malaria and Ascaris.

CONCLUSION

In this cohort of Nigerian preschool children, malaria infection was the major contributor to anaemia status. Ascaris co-infection neither exacerbated nor ameliorated the severity of malarial anaemia.

Identification of a high diversity of Cryptosporidium species genotypes and subtypes in a pediatric population in Nigeria

A longitudinal study was conducted to determine the epidemiology of Cryptosporidium in 1,636 children in Nigeria. Oocyst prevalence ranged from 15.6% to 19.6% over one year. Cryptosporidium hominis (34), C. parvum (25), C. parvum/C. hominis (4), C. meleagridis (5), Cryptosporidium rabbit genotype (5), Cryptosporidium cervine genotype (3), and C. canis (1) were identified by polymerase chain reaction-restriction fragment length polymorphism analysis. Glycoprotein 60 subgenotyping showed that 28 amplifiable C. hominis isolates consisted of 12 subtypes that belonged to 5 subtype families (Ia, Ib, Id, Ie, and 1 novel subtype family, Ih) and 23 amplifiable C. parvum isolates consisted of 6 subtypes that belonged to 4 subtype families (IIa, IIc, Iii, and IIm). Three C. meleagridis isolates sub-genotyped by sequence analysis of the small subunit ribosomal RNA gene fragment were type 1. This study is the first one to genetically characterize Cryptosporidium species and subtypes in Nigeria and highlights the presence of a high Cryptosporidium diversity in this pediatric population.

Patterns of soil-transmitted helminth infection and impact of four-monthly albendazole treatments in preschool children from semi-urban communities in Nigeria: a double-blind placebo-controlled randomised trial

Background

Children aged between one and five years are particularly vulnerable to disease caused by soil-transmitted helminths (STH). Periodic deworming has been shown to improve growth, micronutrient status (iron and vitamin A), and motor and language development in preschool children and justifies the inclusion of this age group in deworming programmes. Our objectives were to describe the prevalence and intensity of STH infection and to investigate the effectiveness of repeated four-monthly albendazole treatments on STH infection in children aged one to four years.

Methods

The study was carried out in four semi-urban villages situated near Ile-Ife, Osun State, Nigeria. The study was a double-blind placebo-controlled randomised trial. Children aged one to four years were randomly assigned to receive either albendazole or placebo every four months for 12 months with a follow-up at 14 months.

Results

The results presented here revealed that 50% of the preschool children in these semi-urban communities were infected by one or more helminths, the most prevalent STH being Ascaris lumbricoides (47.6%). Our study demonstrated that repeated four-monthly anthelminthic treatments with albendazole were successful in reducing prevalence and intensity of A. lumbricoides infections. At the end of the follow-up period, 12% and 43% of the children were infected with A. lumbricoides and mean epg was 117 (S.E. 50) and 1740 (S.E. 291) in the treatment and placebo groups respectively compared to 45% and 45% of the children being infected with Ascaris and mean epg being 1095 (S.E. 237) and 1126 (S.E. 182) in the treatment and placebo group respectively at baseline.

Conclusion

Results from this study show that the moderate prevalence and low intensity of STH infection in these preschool children necessitates systematic treatment of the children in child health programmes.

Trial Registration

Current controlled trials ISRCTN44215995.