Artemisinin-naphthoquine versus artemether-lumefantrine for uncomplicated malaria in Papua New Guinean children: an open-label randomized trial

BACKGROUND

Artemisinin combination therapies (ACTs) with broad efficacy are needed where multiple Plasmodium species are transmitted, especially in children, who bear the brunt of infection in endemic areas. In Papua New Guinea (PNG), artemether-lumefantrine is the first-line treatment for uncomplicated malaria, but it has limited efficacy against P. vivax. Artemisinin-naphthoquine should have greater activity in vivax malaria because the elimination of naphthoquine is slower than that of lumefantrine. In this study, the efficacy, tolerability, and safety of these ACTs were assessed in PNG children aged 0.5-5 y.

METHODS AND FINDINGS

An open-label, randomized, parallel-group trial of artemether-lumefantrine (six doses over 3 d) and artemisinin-naphthoquine (three daily doses) was conducted between 28 March 2011 and 22 April 2013. Parasitologic outcomes were assessed without knowledge of treatment allocation. Primary endpoints were the 42-d P. falciparum PCR-corrected adequate clinical and parasitologic response (ACPR) and the P. vivax PCR-uncorrected 42-d ACPR. Non-inferiority and superiority designs were used for falciparum and vivax malaria, respectively. Because the artemisinin-naphthoquine regimen involved three doses rather than the manufacturer-specified single dose, the first 188 children underwent detailed safety monitoring. Of 2,542 febrile children screened, 267 were randomized, and 186 with falciparum and 47 with vivax malaria completed the 42-d follow-up. Both ACTs were safe and well tolerated. P. falciparum ACPRs were 97.8% and 100.0% in artemether-lumefantrine and artemisinin-naphthoquine-treated patients, respectively (difference 2.2% [95% CI -3.0% to 8.4%] versus -5.0% non-inferiority margin, p = 0.24), and P. vivax ACPRs were 30.0% and 100.0%, respectively (difference 70.0% [95% CI 40.9%-87.2%], p<0.001). Limitations included the exclusion of 11% of randomized patients with sub-threshold parasitemias on confirmatory microscopy and direct observation of only morning artemether-lumefantrine dosing.

CONCLUSIONS

Artemisinin-naphthoquine is non-inferior to artemether-lumefantrine in PNG children with falciparum malaria but has greater efficacy against vivax malaria, findings with implications in similar geo-epidemiologic settings within and beyond Oceania.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12610000913077. Please see later in the article for the Editors' Summary.

Viral pathogens in children hospitalized with features of central nervous system infection in a malaria-endemic region of Papua New Guinea

BACKGROUND

Viral central nervous system (CNS) infections are common in countries where malaria is endemic but, due to limited laboratory facilities, few studies have systematically examined the prevalence and clinical consequences of the presence of viruses in cerebrospinal fluid (CSF) from children with suspected CNS infection.

METHODS

We performed a prospective study of Papua New Guinean children hospitalized with signs and symptoms of CNS infection. CSF samples from 300 children without proven bacterial/fungal meningitis were analyzed for human herpes viruses (HHV), picornaviruses, influenza, adenoviruses, flaviviruses and bacteria.

RESULTS

Fifty-five children (18%) had viral (42), bacterial (20) or both viral and bacterial (7) nucleic acids (NA) identified in their CSF. Human herpes viruses accounted for 91% of all viruses found. The identification of viral or bacterial NA was not associated with any characteristic clinical features. By contrast, malaria was associated with increased identification of viral and bacterial NA and with impaired consciousness, multiple convulsions and age. Malaria was also inversely associated with an adverse outcome. Amongst children with HHV infection, those with HHV-6 and -7 were younger, were more likely have impaired consciousness and had a higher proportion of adverse outcomes than children with CMV. Dengue and enteroviral infections were infrequent. Adenoviral and influenza infections were not identified.

CONCLUSION

Infections with HHV-6, HHV-7, dengue and enterovirus have the potential to cause serious CNS disease in young PNG children. However most HHVs in this malaria-endemic setting should be considered to be the result of reactivation from a latent reservoir without clinical sequelae.

Diagnostic criteria for depression in type 2 diabetes: a data-driven approach

Background

While depression is a frequent psychiatric comorbid condition in diabetes and has significant clinical impact, the syndromal profile of depression and anxiety symptoms has not been examined in detail.

Aims

To determine the syndromal pattern of the depression and anxiety spectrum in a large series of patients with type 2 diabetes, as determined using a data-driven approach based on latent class analysis (LCA).

Method

Type 2 diabetes participants from the observational community-based Fremantle Diabetes Study Phase II underwent assessment of lifetime depression using the Brief Lifetime Depression Scale, the Patient Health Questionnaire 9-item version (PHQ-9) for current depression symptoms, and the Generalized Anxiety Disorder Scale that was specifically developed and validated for this study. The main outcome measure was classes of patients with a specific syndromal profile of depression and anxiety symptoms based on LCA.

Results

LCA identified four classes that were interpreted as “major anxious depression”, “minor anxious depression”, “subclinical anxiety”, and “no anxious depression”. All nine DSM-IV/5 diagnostic criteria for major depression identified a class with a high frequency of major depression. All symptoms of anxiety had similar high probabilities as symptoms of depression for the “major depression-anxiety” class. There were significant differences between classes in terms of history of depression and anxiety, use of psychoactive medication, and diabetes-related variables.

Conclusions

Patients with type 2 diabetes show specific profiles of depression and anxiety. Anxiety symptoms are an integral part of major depression in type 2 diabetes. The different classes identified here provide empirically validated phenotypes for future research.

Population pharmacokinetics of intravenous artesunate: a pooled analysis of individual data from patients with severe malaria

There are ~660,000 deaths from severe malaria each year. Intravenous artesunate (i.v. ARS) is the first-line treatment in adults and children. To optimize the dosing regimen of i.v. ARS, the largest pooled population pharmacokinetic study to date of the active metabolite dihydroartemisinin (DHA) was performed. The pooled dataset consisted of 71 adults and 195 children with severe malaria, with a mixture of sparse and rich sampling within the first 12 h after drug administration. A one-compartment model described the population pharmacokinetics of DHA adequately. Body weight had the greatest impact on DHA pharmacokinetics, resulting in lower DHA exposure for smaller children (6–10 kg) than adults. Post hoc estimates of DHA exposure were not significantly associated with parasitological outcomes. Comparable DHA exposure in smaller children and adults after i.v. ARS was achieved under a dose modification for intramuscular ARS proposed in a separate analysis of children.

Self-awareness of foot health status in patients with Type 2 diabetes: the Fremantle Diabetes Study Phase II

AIMS

To determine self-awareness of diabetes-related foot problems and its associates in a community-based cohort of people with Type 2 diabetes.

METHODS

A survey concerning diabetic foot problems was administered to 358 consecutive patients with Type 2 diabetes [mean ± SD age 67.4 ± 10.8 years, 56.1% males, median (interquartile range) diabetes duration 9.0 (3.9-16.8) years] attending for detailed clinical, biochemical and questionnaire assessment as part of the longitudinal observational Fremantle Diabetes Study Phase II.

RESULTS

Compared with the 213 patients (59.5%) who considered their feet to be normal, the 145 (40.5%) who considered their feet to be abnormal were older, had longer diabetes duration and were more likely to have sensory neuropathic symptoms and self-reported poor circulation (P < 0.001). In those who considered their feet to be normal, 67.9% had peripheral sensory neuropathy (score >2/8 on the Michigan Neuropathy Screening Instrument clinical portion), 9.9% had an ankle-brachial index < 0.9, 6.1% had both peripheral sensory neuropathy and an ankle-brachial index < 0.90, and 86.9% had one or more features on inspection, such as deformity, dry skin, callus and fissures that could facilitate more serious complications, despite the majority having had at least one foot examination by a healthcare professional in the previous year.

CONCLUSIONS

Self-assessment of diabetes-related foot problems by patients in the Fremantle Diabetes Study Phase II was unreliable. The present data suggest that self-perceived foot health should be assessed together with foot examination findings. Intensive education and monitoring may be necessary in those who consider their feet to be normal but who have neurovascular, structural and/or other precursors of serious foot pathology.

Accuracy of cerebrospinal leucocyte count, protein and culture for the diagnosis of acute bacterial meningitis: a comparative study using Bayesian latent class analysis

OBJECTIVE

To examine the utility of laboratory methods other than bacterial culture in diagnosing acute bacterial meningitis (ABM).

METHODS

Bayesian latent class analysis was used to estimate diagnostic precision of cerebrospinal fluid (CSF) culture, leucocyte counts and protein concentrations for ABM in Melanesian children.

RESULTS

With a cut-off of ≥20 leucocytes/mm(3) , the area under the receiver operating characteristic curve (AUC ROC) was >97.5% for leucocyte counts. A lower (93%) AUC ROC was observed for CSF protein concentrations ≥1 g/l. CSF culture had poor sensitivity and high specificity.

CONCLUSION

Leucocyte counts provide sufficient diagnostic precision to aid clinical decision-making in ABM.

A longitudinal study of foot ulceration and its risk factors in community-based patients with type 2 diabetes: the Fremantle Diabetes Study

AIMS

To determine the prevalence and associates of foot ulcer, and the subsequent incidence and predictors of first-ever hospitalisation for this complication, in well-characterised community-based patients with type 2 diabetes.

METHODS

Baseline foot ulceration was ascertained in 1296 patients (mean age 64 years, 48.6% male, median diabetes duration 4.0 years) recruited to the longitudinal Fremantle Diabetes Study between 1993 and 1996. Incident hospitalisation for foot ulceration was monitored through validated data linkage until end-December 2010.

RESULTS

At baseline, 16 participants (1.2%) had a foot ulcer which was independently associated with intermittent claudication, peripheral sensory neuropathy (PSN) and diabetes duration (P≤0.01). The incidence of hospitalisation for this complication in those without prior/prevalent foot ulceration was 5.21 per 1000 patient-years. This rate and other published data suggest that 1 in 7-10 foot ulcers require hospitalisation. In a Cox proportional hazards model, intermittent claudication and PSN were significant independent predictors of time to admission with foot ulceration, in addition to retinopathy, cerebrovascular disease, HbA1c, alcohol consumption, renal impairment, peripheral arterial disease and pulse pressure (P≤0.038).

CONCLUSIONS

These data confirm PSN as an important risk factor for foot ulceration but, in contrast to some other studies, peripheral arterial disease was also a major independent contributor. Associations between hospitalisation for foot ulcer and both retinopathy and raised pulse pressure suggest a role for local microvascular dysfunction, while alcohol may have non-neuropathic toxic effects on skin/subcutaneous structures. The multifactorial nature of foot ulceration complicating type 2 diabetes may have implications for its management.

Dipeptidyl peptidase-4 inhibitors: pharmacokinetics, efficacy, tolerability and safety in renal impairment

The dipeptidyl peptidase-4 (DPP-4) inhibitors are a new class of blood glucose-lowering therapy with proven efficacy, tolerability and safety. Four of the five commercially available DPP-4 inhibitors are subject to significant renal clearance, and pharmacokinetic studies in people with renal impairment have led to lower recommended doses based on creatinine clearance in order to prevent drug accumulation. Data from these pharmacokinetic studies and from supratherapeutic doses in healthy individuals and people with uncomplicated diabetes during development suggest, however, that there is a wide therapeutic margin. This should protect against toxicity if people with renal impairment are inadvertently prescribed higher doses than recommended. Doses appropriate to renal function are associated with reductions in HbA1c that are equivalent to those observed in people with type 2 diabetes who do not have renal impairment. Recent large-scale cardiovascular safety trials of saxagliptin and alogliptin have identified heart failure as a potential concern and renal impairment may increase the risk of this complication. Although the incidence of pancreatitis does not appear to be significantly increased by DPP-4 inhibitor therapy, renal impairment is also an independent risk factor. Additional data from other ongoing DPP-4 inhibitor cardiovascular safety trials should provide a more precise assessment of the risks of these uncommon complications, including in people with renal impairment.

Comparison of three methods for detection of gametocytes in Melanesian children treated for uncomplicated malaria

Background

Gametocytes are the transmission stages of Plasmodium parasites, the causative agents of malaria. As their density in the human host is typically low, they are often undetected by conventional light microscopy. Furthermore, application of RNA-based molecular detection methods for gametocyte detection remains challenging in remote field settings. In the present study, a detailed comparison of three methods, namely light microscopy, magnetic fractionation and reverse transcriptase polymerase chain reaction for detection of Plasmodium falciparum and Plasmodium vivax gametocytes was conducted.

Methods

Peripheral blood samples from 70 children aged 0.5 to five years with uncomplicated malaria who were treated with either artemether-lumefantrine or artemisinin-naphthoquine were collected from two health facilities on the north coast of Papua New Guinea. The samples were taken prior to treatment (day 0) and at pre-specified intervals during follow-up. Gametocytes were measured in each sample by three methods: i) light microscopy (LM), ii) quantitative magnetic fractionation (MF) and, iii) reverse transcriptase PCR (RTPCR). Data were analysed using censored linear regression and Bland and Altman techniques.

Results

MF and RTPCR were similarly sensitive and specific, and both were superior to LM. Overall, there were approximately 20% gametocyte-positive samples by LM, whereas gametocyte positivity by MF and RTPCR were both more than two-fold this level. In the subset of samples collected prior to treatment, 29% of children were positive by LM, and 85% were gametocyte positive by MF and RTPCR, respectively.

Conclusions

The present study represents the first direct comparison of standard LM, MF and RTPCR for gametocyte detection in field isolates. It provides strong evidence that MF is superior to LM and can be used to detect gametocytaemic patients under field conditions with similar sensitivity and specificity as RTPCR.

Electronic supplementary material

The online version of this article (doi:10.1186/1475-2875-13-319) contains supplementary material, which is available to authorized users.

HDL-C and HDL-C/ApoA-I predict long-term progression of glycemia in established type 2 diabetes

OBJECTIVE

Low HDL cholesterol (HDL-C) and small HDL particle size may directly promote hyperglycemia. We evaluated associations of HDL-C, apolipoprotein A-I (apoA-I), and HDL-C/apoA-I with insulin secretion, insulin resistance, HbA1c, and long-term glycemic deterioration, reflected by initiation of pharmacologic glucose control.

RESEARCH DESIGN AND METHODS

The 5-year Fenofibrate Intervention and Event Lowering in Diabetes (FIELD) study followed 9,795 type 2 diabetic subjects. We calculated baseline associations of fasting HDL-C, apoA-I, and HDL-C/apoA-I with HbA1c and, in those not taking exogenous insulin (n = 8,271), with estimated β-cell function (homeostasis model assessment of β-cell function [HOMA-B]) and insulin resistance (HOMA-IR). Among the 2,608 subjects prescribed lifestyle only, Cox proportional hazards analysis evaluated associations of HDL-C, apoA-I, and HDL-C/apoA-I with subsequent initiation of oral hypoglycemic agents (OHAs) or insulin.

RESULTS

Adjusted for age and sex, baseline HDL-C, apoA-I, and HDL-C/apoA-I were inversely associated with HOMA-IR (r = -0.233, -0.134, and -0.230; all P < 0.001; n = 8,271) but not related to HbA1c (all P > 0.05; n = 9,795). ApoA-I was also inversely associated with HOMA-B (r = -0.063; P = 0.002; n = 8,271) adjusted for age, sex, and HOMA-IR. Prospectively, lower baseline HDL-C and HDL-C/apoA-I levels predicted greater uptake (per 1-SD lower: hazard ratio [HR] 1.13 [CI 1.07-1.19], P < 0.001; and HR 1.16 [CI 1.10-1.23], P < 0.001, respectively) and earlier uptake (median 12.9 and 24.0 months, respectively, for quartile 1 vs. quartile 4; both P < 0.01) of OHAs and insulin, with no difference in HbA1c thresholds for initiation (P = 0.87 and P = 0.81). Controlling for HOMA-IR and triglycerides lessened both associations, but HDL-C/apoA-I remained significant.

CONCLUSIONS

HDL-C, apoA-I, and HDL-C/apoA-I were associated with concurrent insulin resistance but not HbA1c. However, lower HDL-C and HDL-C/apoA-I predicted greater and earlier need for pharmacologic glucose control.

Effect of continuous positive airway pressure therapy on sexual function and serum testosterone in males with type 2 diabetes and obstructive sleep apnoea

OBJECTIVE

There have been no studies of the effect of continuous positive airway pressure (CPAP) therapy on erectile dysfunction (ED) and serum testosterone in men with type 2 diabetes and obstructive sleep apnoea (OSA), a patient group at increased risk of ED and hypogonadism. The aim of this study was to determine whether CPAP improves sexual and gonadal function in males with type 2 diabetes and a pre-CPAP apnoea-hypopnoea index >15/h.

DESIGN

Substudy of a trial assessing the effect of 3 months of CPAP on cardiovascular risk in type 2 diabetes.

PATIENTS

Of 35 males starting CPAP, 27 (mean ± SD age 65.4 ± 9.6 years, median [interquartile range] diabetes duration 12.1 [5.2-15.3] years) completed the trial.

MEASUREMENTS

Serum total and free testosterone, responses to the Androgen Deficiency in the Aging Aale (ADAM) and Sexual Health Inventory for Men (SHIM) questionnaires.

RESULTS

There were no significant changes in mean total or free testosterone (baseline concentrations 12.7 ± 4.5 nm and 0.26 ± 0.07 pm, respectively), or SHIM score (baseline 13 [5-17]), after 3 months of CPAP (P > 0.20). The ADAM score (baseline 6.2 ± 2.1) fell after 1 month (to 5.0 ± 2.6) and was maintained at this level at 3 months (P = 0.015). The Epworth Sleepiness Scale score decreased and self-reported physical activity increased over 3 months (P ≤ 0.017) without a change in body mass index (P = 1.00).

CONCLUSIONS

These findings imply that CPAP therapy improves somnolence and promotes exercise in men with type 2 diabetes, but that there is no direct benefit for gonadal or sexual function.

Incidence and precipitants of hospitalization for pancreatitis in people with diabetes: the Fremantle Diabetes Study

AIMS

To determine the relative risk of pancreatitis in diabetes, and to establish whether diabetes-related as well as recognized risk factors contribute.

METHODS

We studied 1426 participants [mean (SD) age 62.1 (13.3) years, 49.6% male, 90.9% type 2 diabetes, median (interquartile range) diabetes duration 4.0 (1.0-10.0) years] from the community-based Fremantle Diabetes Study Phase I and 5663 matched residents without diabetes from the same geographical area. Pancreatitis hospitalizations between 1982 and 2010 were ascertained using validated data linkage. For Fremantle Diabetes Study Phase I participants, chart review provided data on the likely causes of pancreatitis.

RESULTS

A total of 21 Fremantle Diabetes Study Phase I participants (1.5%) were hospitalized for pancreatitis before study entry vs 29 (0.5%) of contemporaneous residents without diabetes. During a mean (SD) of 12.1 (5.4) years of follow-up from entry, 22 (1.6%) Fremantle Diabetes Study Phase I participants were hospitalized for a first-ever episode of pancreatitis on 37 occasions (1.31/1000 person-years) compared with 58 (1.0%) residents without diabetes on 81 occasions during a mean (SD) 13.6 (4.8) years (0.75/1000 person-years). The age- and sex-adjusted hazard ratio (95% CI) for first-ever pancreatitis hospitalization in Fremantle Diabetes Study Phase I participants was 1.73 (1.06-2.83; P=0.029). Chart review of 17 of the 22 Fremantle Diabetes Study Phase I participants (77%) with incident pancreatitis and available case notes revealed that four (24%) presented without objective evidence of pancreatitis, seven (41%) presented with cholelithiasis, three (18%) with excessive alcohol consumption, two (12%) as a complication of elective endoscopic retrograde cholangiopancreatography, and one (6%) with hypertriglyceridaemia.

CONCLUSION

Consistent with previously published data, the risk of pancreatitis was higher in community-dwelling Fremantle Diabetes Study Phase I participants but conventional precipitants accounted for confirmed cases. These data question whether diabetes-specific risk factors cause or contribute to pancreatitis.

Polymorphisms in Plasmodium falciparum chloroquine resistance transporter and multidrug resistance 1 genes: parasite risk factors that affect treatment outcomes for P. falciparum malaria after artemether-lumefantrine and artesunate-amodiaquine

Adequate clinical and parasitologic cure by artemisinin combination therapies relies on the artemisinin component and the partner drug. Polymorphisms in the Plasmodium falciparum chloroquine resistance transporter (pfcrt) and P. falciparum multidrug resistance 1 (pfmdr1) genes are associated with decreased sensitivity to amodiaquine and lumefantrine, but effects of these polymorphisms on therapeutic responses to artesunate-amodiaquine (ASAQ) and artemether-lumefantrine (AL) have not been clearly defined. Individual patient data from 31 clinical trials were harmonized and pooled by using standardized methods from the WorldWide Antimalarial Resistance Network. Data for more than 7,000 patients were analyzed to assess relationships between parasite polymorphisms in pfcrt and pfmdr1 and clinically relevant outcomes after treatment with AL or ASAQ. Presence of the pfmdr1 gene N86 (adjusted hazards ratio = 4.74, 95% confidence interval = 2.29 – 9.78, P < 0.001) and increased pfmdr1 copy number (adjusted hazards ratio = 6.52, 95% confidence interval = 2.36–17.97, P < 0.001) were significant independent risk factors for recrudescence in patients treated with AL. AL and ASAQ exerted opposing selective effects on single-nucleotide polymorphisms in pfcrt and pfmdr1. Monitoring selection and responding to emerging signs of drug resistance are critical tools for preserving efficacy of artemisinin combination therapies; determination of the prevalence of at least pfcrt K76T and pfmdr1 N86Y should now be routine.

Continuous infusions of meropenem in ambulatory care: clinical efficacy, safety and stability

OBJECTIVES

Concerns regarding the clinical impact of meropenem instability in continuous infusion (CI) devices may contribute to inconsistent uptake of this method of administration across outpatient parenteral antimicrobial therapy (OPAT) services.

METHODS

We retrospectively reviewed the clinical efficacy and safety of CIs of meropenem in two Australian tertiary hospitals and assessed its stability under simulated OPAT conditions including in elastomeric infusion devices containing 1% (2.4 g) or 2% (4.8 g) concentrations at either 'room temperature' or 'cooled' conditions. Infusate aliquots were assayed at different time-points over 24 hours.

RESULTS

Forty-one (82%) of 50 patients had clinical improvement or were cured. Adverse patient outcomes including hemato-, hepato- and nephrotoxicity were infrequent. Cooled infusers with 1% meropenem had a mean 24-hour recovery of 90.3%. Recoveries of 1% and 2% meropenem at room temperature and 2% under cooled conditions were 88%, 83% and 87%, respectively. Patients receiving 1% meropenem are likely to receive >95% of the maximum deliverable dose (MDD) over a 24-hour period whilst patients receiving 2% meropenem should receive 93% and 87% of the MDD under cooled and room temperature conditions, respectively.

CONCLUSIONS

Meropenem infusers are likely to deliver ∼95% MDD and maintain effective plasma concentrations throughout the dosing period. These data reflect our local favourable clinical experience with meropenem CIs.

Quality of antimalarial drugs and antibiotics in Papua New Guinea: a survey of the health facility supply chain

Background

Poor-quality life-saving medicines are a major public health threat, particularly in settings with a weak regulatory environment. Insufficient amounts of active pharmaceutical ingredients (API) endanger patient safety and may contribute to the development of drug resistance. In the case of malaria, concerns relate to implications for the efficacy of artemisinin-based combination therapies (ACT). In Papua New Guinea (PNG), Plasmodium falciparum and P. vivax are both endemic and health facilities are the main source of treatment. ACT has been introduced as first-line treatment but other drugs, such as primaquine for the treatment of P. vivax hypnozoites, are widely available. This study investigated the quality of antimalarial drugs and selected antibiotics at all levels of the health facility supply chain in PNG.

Methods and Findings

Medicines were obtained from randomly sampled health facilities and selected warehouses and hospitals across PNG and analysed for API content using validated high performance liquid chromatography (HPLC). Of 360 tablet/capsule samples from 60 providers, 9.7% (95% CI 6.9, 13.3) contained less, and 0.6% more, API than pharmacopoeial reference ranges, including 29/37 (78.4%) primaquine, 3/70 (4.3%) amodiaquine, and one sample each of quinine, artemether, sulphadoxine-pyrimethamine and amoxicillin. According to the package label, 86.5% of poor-quality samples originated from India. Poor-quality medicines were found in 48.3% of providers at all levels of the supply chain. Drug quality was unrelated to storage conditions.

Conclusions

This study documents the presence of poor-quality medicines, particularly primaquine, throughout PNG. Primaquine is the only available transmission-blocking antimalarial, likely to become important to prevent the spread of artemisinin-resistant P. falciparum and eliminating P. vivax hypnozoites. The availability of poor-quality medicines reflects the lack of adequate quality control and regulatory mechanisms. Measures to stop the availability of poor-quality medicines should include limiting procurement to WHO prequalified products and implementing routine quality testing.

Accuracy of initial clinical diagnosis of acute bacterial meningitis in children from a malaria-endemic area of Papua New Guinea

BACKGROUND

The diagnosis of acute bacterial meningitis (ABM) is challenging in resource-limited settings where cerebral malaria and viral encephalitis are also common.

METHODS

To assess the accuracy of an initial clinical diagnosis of ABM in a malaria-endemic area of Papua New Guinea (PNG), a retrospective chart review of hospitalized children aged 2 months to 10 years was conducted.

RESULTS

Of the 481 eligible children, 240 had an initial clinical diagnosis of ABM that was confirmed independently by trained research staff under standardized conditions, with laboratory support in only 84 (17.5%; 84/481). When compared with the final laboratory-confirmed diagnosis, an initial diagnosis of ABM had a sensitivity, specificity, positive predictive value and negative predictive value of 76% (95% CI 66-85%), 56% (95% CI 51-61%), 27% (95% CI 21-33) and 92% (95% CI 87-95%), respectively. There was discordance between initial and final diagnosis of ABM in 196 children; 176 initially considered to have ABM had an alternative diagnosis, while 20 without an initial diagnosis of ABM were confirmed to have ABM.

CONCLUSION

These data show that initial misdiagnosis of ABM is common in a malaria-endemic area of PNG. A diagnostic algorithm using standardized assessment for meningeal irritation, coma and malaria parasitological testing needs further evaluation in this setting.

Intensification of medication and glycaemic control among patients with type 2 diabetes - the ADVANCE trial

AIMS

The aim of this study was to assess associations between patient characteristics, intensification of blood glucose-lowering treatment through oral glucose-lowering therapy and/or insulin and effective glycaemic control in type 2 diabetes.

METHODS

11 140 patients from the Action in Diabetes and Vascular disease: preterAx and diamicroN-MR Controlled Evaluation (ADVANCE) trial who were randomized to intensive glucose control or standard glucose control and followed up for a median of 5 years were categorized into two groups: effective glycaemic control [haemoglobin A1c (HbA1c) ≤ 7.0% or a proportionate reduction in HbA1c over 10%] or ineffective glycaemic control (HbA1c > 7.0% and a proportionate reduction in HbA1c less than or equal to 10%). Therapeutic intensification was defined as addition of an oral glucose-lowering agent or commencement of insulin. Pooled logistic regression models examined the associations between patient factors, intensification and effective glycaemic control.

RESULTS

A total of 7768 patients (69.7%), including 3198 in the standard treatment group achieved effective glycaemic control. Compared to patients with ineffective control, patients with effective glycaemic control had shorter duration of diabetes and lower HbA1c at baseline and at the time of treatment intensification. Treatment intensification with addition of an oral agent or commencement of insulin was associated with a 107% [odds ratio, OR: 2.07 (95% confidence interval, CI: 1.95-2.20)] and 152% [OR: 2.52 (95% CI: 2.30-2.77)] greater chance of achieving effective glycaemic control, respectively. These associations were robust after adjustment for several baseline characteristics and not modified by the number of oral medications taken at the time of treatment intensification.

CONCLUSIONS

Effective glycaemic control was associated with treatment intensification at lower HbA1c levels at all stages of the disease course and in both arms of the ADVANCE trial.

Comparison of an assumed versus measured leucocyte count in parasite density calculations in Papua New Guinean children with uncomplicated malaria

BACKGROUND

The accuracy of the World Health Organization method of estimating malaria parasite density from thick blood smears by assuming a white blood cell (WBC) count of 8,000/μL has been questioned in several studies. Since epidemiological investigations, anti-malarial efficacy trials and routine laboratory reporting in Papua New Guinea (PNG) have all relied on this approach, its validity was assessed as part of a trial of artemisinin-based combination therapy, which included blood smear microscopy and automated measurement of leucocyte densities on Days 0, 3 and 7.

RESULTS

168 children with uncomplicated malaria (median (inter-quartile range) age 44 (39-47) months) were enrolled, 80.3% with Plasmodium falciparum monoinfection, 14.9% with Plasmodium vivax monoinfection, and 4.8% with mixed P. falciparum/P. vivax infection. All responded to allocated therapy and none had a malaria-positive slide on Day 3. Consistent with a median baseline WBC density of 7.3 (6.5-7.8) × 10(9)/L, there was no significant difference in baseline parasite density between the two methods regardless of Plasmodium species. Bland Altman plots showed that, for both species, the mean difference between paired parasite densities calculated from assumed and measured WBC densities was close to zero. At parasite densities <10,000/μL by measured WBC, almost all between-method differences were within the 95% limits of agreement. Above this range, there was increasing scatter but no systematic bias.

CONCLUSIONS

Diagnostic thresholds and parasite clearance assessment in most PNG children with uncomplicated malaria are relatively robust, but accurate estimates of a higher parasitaemia, as a prognostic index, requires formal WBC measurement.

Personality traits, self-care behaviours and glycaemic control in type 2 diabetes: the Fremantle diabetes study phase II

AIMS

To determine whether the personality traits of conscientiousness and agreeableness are associated with self-care behaviours and glycaemia in Type 2 diabetes.

METHODS

The Big Five Inventory personality traits Agreeableness, Conscientiousness, Extraversion, Neuroticism and Openness were determined along with a range of other variables in 1313 participants with Type 2 diabetes (mean age 65.8 ± 11.1 years; 52.9% men) undertaking their baseline assessment as part of the community-based longitudinal observational Fremantle Diabetes Study Phase II. Age- and sex-adjusted generalized linear modelling was used to determine whether personality was associated with BMI, smoking, self-monitoring of blood glucose and medication taking. Multivariable regression was used to investigate which traits were independently associated with these self-care behaviours and HbA1c .

RESULTS

Patients with higher conscientiousness were less likely to be obese or smoke, and more likely to perform self-monitoring of blood glucose and take their medications (P ≤ 0.019), with similar independent associations in multivariate models (P ≤ 0.024). HbA1c was independently associated with younger age, indigenous ethnicity, higher BMI, longer diabetes duration, diabetes treatment, self-monitoring of blood glucose (negatively) and less medication taking (P ≤ 0.009), but no personality trait added to the model.

CONCLUSIONS

Although there was no independent association between personality traits and HbA1c , the relationship between high conscientiousness and low BMI and beneficial self-care behaviours suggests an indirect positive effect on glycaemia. Conscientiousness could be augmented by the use of impulse control training as part of diabetes management.

Incidence and predictors of hospitalization for tendon rupture in type 2 diabetes: the Fremantle diabetes study

AIMS

To determine the incidence and predictors of tendon ruptures requiring hospitalization of representative patients with type 2 diabetes.

METHODS

A total of 1296 patients from the longitudinal observational Fremantle Diabetes Study, Phase I, and 5159 de-identified age- and sex-matched control subjects without diabetes from the same urban area were studied. The patients' mean (sd) age was 64.0 (11.3) years and 48.6% of them were male. Their median (interquartile range) diabetes duration was 4.0 (1.0-9.0) years. The main outcome assessed was any tendon rupture requiring hospitalization in the Fremantle Diabetes Study subjects and the matched control subjects. Independent predictors of spontaneous ruptures in the patients from the Fremantle Diabetes Study were assessed using Cox proportional hazards modelling.

RESULTS

The incidence rate ratio for any tendon rupture requiring hospitalization in patients vs control subjects was 1.44 (95% CI 1.10-1.87; P = 0.005). Independent predictors of spontaneous ruptures in patients were BMI [hazard ratio 1.05 (95% CI 1.002-1.10] for 1 kg/m2 increase; P = 0.010] and alcohol consumption [hazard ratio 1.52 (95% CI 1.11-2.09) for √1 standard drink/day increase; P = 0.010]. Adjustment of the incidence rate ratio for overall rupture requiring hospitalization for these variables using the BMI and alcohol consumption data from the contemporary Australian general population suggested it could be as high as 1.84.

CONCLUSIONS

There is a greater risk of tendon rupture requiring hospitalization in people with type 2 diabetes. Alcohol consumption and adiposity are potentially modifiable risk factors of spontaneous ruptures in patients with diabetes.

γδ T cells and CD14+ monocytes are predominant cellular sources of cytokines and chemokines associated with severe malaria

BACKGROUND

Severe malaria (SM) is associated with high levels of cytokines such as tumor necrosis factor (TNF), interleukin 1 (IL-1), and interleukin 6 (IL-6). The role of chemokines is less clear, as is their cellular source.

METHODS

In a case-control study of children with SM (n = 200), uncomplicated malaria (UM) (n = 153) and healthy community controls (HC) (n = 162) in Papua, New Guinea, we measured cytokine/chemokine production by peripheral blood mononuclear cells (PBMCs) stimulated with live Plasmodium falciparum parasitized red blood cells (pRBC). Cellular sources were determined. Associations between immunological endpoints and clinical/parasitological variables were tested.

RESULTS

Compared to HC and UM, children with SM produced significantly higher IL-10, IP-10, MIP-1βm and MCP-2. TNF and MIP-1α were significantly higher in the SM compared to the UM group. IL-10, IL-6, MIP-1α, MIP-1β, and MCP-2 were associated with increased odds of SM. SM syndromes were associated with distinct cytokine/chemokine response profiles compared to UM cases. TNF, MIP-1β, and MIP-1α were produced predominantly by monocytes and γδ T cells, and IL-10 by CD4(+) T cells.

CONCLUSIONS

Early/innate PBMC responses to pRBC in vitro are informative as to cytokines/chemokines associated with SM. Predominant cellular sources are monocytes and γδ T cells. Monocyte-derived chemokines support a role for monocyte infiltrates in the etiology of SM.

Clinical features and outcome in children with severe Plasmodium falciparum malaria: a meta-analysis

Background

Although global malaria mortality is declining, estimates may not reflect better inpatient management of severe malaria (SM) where reported case fatality rates (CFRs) vary from 1–25%.

Methods

A meta-analysis of prospective studies of SM was conducted to examine i) whether hypothesized differences between clinical features and outcome in Melanesian compared with African or Asian children really exist, and ii) to explore temporal changes in overall and complication-specific CFRs. The proportions of different SM complications and, overall and complication-specific CFRs were incorporated into the meta-analysis. Adjustments were made for study-level covariates including geographic region, SM definition, artemisinin treatment, median age of participants and time period.

Findings

Sixty-five studies were included. Substantial heterogeneity (I²>80%) was demonstrated for most outcomes. SM definition contributed to between-study heterogeneity in proportions of cerebral malaria (CM), metabolic acidosis (MA), severe anemia and overall CFR, whilst geographic region was a significant moderator in for CM and hypoglycemia (HG) rates. Compared with their African counterparts, Melanesian children had lower rates of HG (10% [CI95 7–13%] versus 1% [0–3%], P<0.05), lower overall CFR (2% [0–4%] versus 7% [6–9%], P<0.05) and lower CM-specific CFR (8% [0–17%] versus 19% [16–21%], P<0.05). There was no temporal trend for overall CFR and CM-specific CFR but declining HG- and MA- specific CFRs were observed.

Interpretation

These data highlight that recent estimates of declining global malaria mortality are not replicated by improved outcomes for children hospitalized with SM. Significant geographic differences in the complication rates and subsequent CFRs exist and provide the first robust confirmation of lower CFRs in Melanesian children, perhaps due to less frequent HG.

Ethnicity and long-term vascular outcomes in Type 2 diabetes: a prospective observational study (UKPDS 83)

AIMS

Evidence of ethnic differences in vascular complications of diabetes has been inconsistent. The aim of this study was to examine the relationship between ethnicity and long-term outcome in a large sample of individuals with newly diagnosed Type 2 diabetes.

METHODS

In a prospective observational study of 4273 UK Prospective Diabetes Study participants followed for a median of 18 years, 3543 (83%) were White Caucasian, 312 (7%) Afro-Caribbean and 418 (10%) Asian Indian. Relative risks for predefined outcomes were assessed comparing Afro-Caribbean and Asian Indian with White Caucasian using accelerated failure time models, with adjustment for cardiovascular risk factors and other potentially confounding variables.

RESULTS

During follow-up, 2468 (58%) participants had any diabetes-related end point, 1037 (24%) a myocardial infarction and 401 (9%) a stroke, and 1782 (42%) died. Asian Indian were at greater risk (relative risk, 95% confidence interval) for any diabetes-related end point (1.18, 1.07-1.29), but at lower risk of all-cause mortality (0.89, 0.80-0.97) and peripheral vascular disease (0.43, 0.23-0.82), vs. White Caucasian. Afro-Caribbean participants were at lower risk for all-cause mortality (0.84, 0.76-0.93), diabetes-related death (0.75, 0.64-0.88), myocardial infarction (0.55, 0.43-0.71) and peripheral vascular disease (0.55, 0.33-0.93) vs. White Caucasian. No ethnicity-related associations were found for stroke or microangiopathy.

CONCLUSIONS

Asian Indian ethnicity is associated with the greatest burden of disease, but not with an increased risk of major vascular complications or death. Afro-Caribbean ethnicity is associated with reduced risk of all-cause and diabetes-related death, myocardial infarction and peripheral vascular disease, suggesting an ethnicity-specific protective mechanism.