Decision tree algorithms predict the diagnosis and outcome of dengue fever in the early phase of illness

Background

Dengue is re-emerging throughout the tropical world, causing frequent recurrent epidemics. The initial clinical manifestation of dengue often is confused with other febrile states confounding both clinical management and disease surveillance. Evidence-based triage strategies that identify individuals likely to be in the early stages of dengue illness can direct patient stratification for clinical investigations, management, and virological surveillance. Here we report the identification of algorithms that differentiate dengue from other febrile illnesses in the primary care setting and predict severe disease in adults.

Methods and Findings

A total of 1,200 patients presenting in the first 72 hours of acute febrile illness were recruited and followed up for up to a 4-week period prospectively; 1,012 of these were recruited from Singapore and 188 from Vietnam. Of these, 364 were dengue RT-PCR positive; 173 had dengue fever, 171 had dengue hemorrhagic fever, and 20 had dengue shock syndrome as final diagnosis. Using a C4.5 decision tree classifier for analysis of all clinical, haematological, and virological data, we obtained a diagnostic algorithm that differentiates dengue from non-dengue febrile illness with an accuracy of 84.7%. The algorithm can be used differently in different disease prevalence to yield clinically useful positive and negative predictive values. Furthermore, an algorithm using platelet count, crossover threshold value of a real-time RT-PCR for dengue viral RNA, and presence of pre-existing anti-dengue IgG antibodies in sequential order identified cases with sensitivity and specificity of 78.2% and 80.2%, respectively, that eventually developed thrombocytopenia of 50,000 platelet/mm³ or less, a level previously shown to be associated with haemorrhage and shock in adults with dengue fever.

Conclusion

This study shows a proof-of-concept that decision algorithms using simple clinical and haematological parameters can predict diagnosis and prognosis of dengue disease, a finding that could prove useful in disease management and surveillance.

Dengue illness appears similar to other febrile illness, particularly in the early stages of disease. Consequently, diagnosis is often delayed or confused with other illnesses, reducing the effectiveness of using clinical diagnosis for patient care and disease surveillance. To address this shortcoming, we have studied 1,200 patients who presented within 72 hours from onset of fever; 30.3% of these had dengue infection, while the remaining 69.7% had other causes of fever. Using body temperature and the results of simple laboratory tests on blood samples of these patients, we have constructed a decision algorithm that is able to distinguish patients with dengue illness from those with other causes of fever with an accuracy of 84.7%. Another decision algorithm is able to predict which of the dengue patients would go on to develop severe disease, as indicated by an eventual drop in the platelet count to 50,000/mm³ blood or below. Our study shows a proof-of-concept that simple decision algorithms can predict dengue diagnosis and the likelihood of developing severe disease, a finding that could prove useful in the management of dengue patients and to public health efforts in preventing virus transmission.

Implications for lipids during replication of enveloped viruses

Enveloped viruses, which include many medically important viruses such as human immunodeficiency virus, influenza virus and hepatitis C virus, are intracellular parasites that acquire lipid envelopes from their host cells. Success of replication is intimately linked to their ability to hijack host cell mechanisms, particularly those related to membrane dynamics and lipid metabolism. Despite recent progress, our knowledge of lipid mediated virus-host interactions remains highly incomplete. In addition, diverse experimental systems are used to study different stages of virus replication thus complicating comparisons. This review aims to present a unifying view of the widely diverse strategies used by enveloped viruses at distinct stages of their replication cycles.

Small-molecule-mediated OGG1 inhibition attenuates pulmonary inflammation and lung fibrosis in a murine lung fibrosis model

Interstitial lung diseases such as idiopathic pulmonary fibrosis (IPF) are caused by persistent micro-injuries to alveolar epithelial tissues accompanied by aberrant repair processes. IPF is currently treated with pirfenidone and nintedanib, compounds which slow the rate of disease progression but fail to target underlying pathophysiological mechanisms. The DNA repair protein 8-oxoguanine DNA glycosylase-1 (OGG1) has significant roles in the modulation of inflammation and metabolic syndromes. Currently, no pharmaceutical solutions targeting OGG1 have been utilized in the treatment of IPF. In this study we show Ogg1-targeting siRNA mitigates bleomycin-induced pulmonary fibrosis in male mice, highlighting OGG1 as a tractable target in lung fibrosis. The small molecule OGG1 inhibitor, TH5487, decreases myofibroblast transition and associated pro-fibrotic gene expressions in fibroblast cells. In addition, TH5487 decreases levels of pro-inflammatory mediators, inflammatory cell infiltration, and lung remodeling in a murine model of bleomycin-induced pulmonary fibrosis conducted in male C57BL6/J mice. OGG1 and SMAD7 interact to induce fibroblast proliferation and differentiation and display roles in fibrotic murine and IPF patient lung tissue. Taken together, these data suggest that TH5487 is a potentially clinically relevant treatment for IPF but further study in human trials is required.

Abnormal coagulation and enhanced fibrinolysis due to lysinuric protein intolerance associates with bleeds and renal impairment

INTRODUCTION

Lysinuric protein intolerance (LPI), a rare autosomal recessive transport disorder of cationic amino acids lysine, arginine and ornithine, affects intestines, lungs, liver and kidneys. LPI patients may display potentially life-threatening bleeding events, which are poorly understood.

AIMS

To characterize alterations in haemostatic and fibrinolytic variables associated with LPI.

METHODS

We enrolled 15 adult patients (8 female) and assessed the clinical ISTH/SSC-BAT bleeding score (BS). A variety of metabolic and coagulation assays, including fibrin generation test derivatives, clotting time (CT) and clot lysis time (CLT), thromboelastometry (ROTEM), and PFA-100 and Calibrated Automated Thrombogram (CAT), were used.

RESULTS

All patients had mild-to-moderate renal insufficiency, and moderate bleeding tendency (BS 4) without spontaneous bleeds. Mild anaemia and thrombocytopenia occurred. Traditional clotting times were normal, but in contrast, CT in fibrin generation test, and especially ROTEM FIBTEM was abnormal. The patients showed impaired primary haemostasis in PFA, irrespective of normal von Willebrand factor activity, but together with lowered fibrinogen and FXIII. Thrombin generation (TG) was reduced in vitro, according to CAT-derived endogenous thrombin potential, but in vivo TG was enhanced in the form of circulating prothrombin fragment 1 and 2 values. Very high D-dimer and plasmin-α2-antiplasmin (PAP) complex levels coincided with shortened CLT in vitro.

CONCLUSIONS

Defective primary haemostasis, coagulopathy, fibrin abnormality (FIBTEM, CT and CLT), low TG in vitro and clearly augmented fibrinolysis (PAP and D-dimer) in vivo were all detected in LPI. Altered fibrin generation and hyperfibrinolysis were associated with the metabolic and renal defect, suggesting a pathogenetic link in LPI.

NHS Health Check programme: a rapid review update

OBJECTIVE

To update a rapid review published in 2017, which evaluated the NHS Health Check programme.

METHODS

An enlarged body of evidence was used to readdress six research objectives from a rapid review published in 2017, relating to the uptake, patient experiences and effectiveness of the NHS Health Check programme. Data sources included MEDLINE, PubMed, Embase, Health Management Information Consortium (HMIC), Cumulative Index of Nursing and Allied Health Literature (CINAHL), Global Health, PsycINFO, the Cochrane Library, NHS Evidence, Google Scholar, Google, ClinicalTrials.gov and the ISRCTN registry, Web of Science, Science Citation Index, The Cochrane Library, NHS Evidence, OpenGrey and hand searching article reference lists. These searches identified records from between January 1996 and December 2019. Screening, data extraction and quality appraisal using the Critical Appraisals Skills Programme checklists were performed in duplicate. Grading of Recommendations Assessment, Development and Evaluations was implemented. Data were synthesised narratively.

RESULTS

697 studies were identified, and 29 new studies included in the review update. The number of published studies on the uptake, patient experiences and effectiveness of the NHS Health Check programme has increased by 43% since the rapid review published in 2017. However, findings from the original review remain largely unchanged. NHS Health Checks led to an overall increase in the detection of raised risk factors and morbidities including diabetes mellitus, hypertension, raised blood pressure, cholesterol and chronic kidney disease. Individuals most likely to attend the NHS Health Check programme included women, persons aged ≥60 years and those from more socioeconomically advantaged backgrounds. Opportunistic invitations increased uptake among men, younger persons and those with a higher deprivation level.

CONCLUSIONS

Although results are inconsistent between studies, the NHS Health Check programme is associated with increased detection of heightened cardiovascular disease risk factors and diagnoses. Uptake varied between population subgroups. Opportunistic invitations may increase uptake.

The Use of Interferometry as an Aid to Studying Flapper-Valve Flow Characteristics

A technique is described for visualizing the air flow over a surface by means of an oil film. The technique is used in conjunction with experimentally determined flapper-plate pressure profiles to examine the flow characteristics of a flapper-nozzle valve used to control air at 425 kPa (4.25 bar). The oil film shows clearly the points of separation and reattachment of the air boundary layer resulting from shock wave and boundary layer interaction.

Possible applications of the technique are discussed and attention is focused on the use of the oil-film technique in conjunction with interferometry as a tool for the rapid determination of the effects caused by changes in nozzle geometry.

Does Dental Caries Increase Risk of Undernutrition in Children?

INTRODUCTION

A systematic review of the evidence on the impact of dental caries on malnutrition risk in children was conducted.

OBJECTIVES

To systematically review published evidence pertaining to the effect of dental caries severity and prevalence on risk of wasting or stunting in children.

METHODS

Four questions relating to caries of the permanent dentition, primary dentition, early childhood caries (ECC), and severe ECC as a risk factor for undernutrition were set. The target population was children aged 0 to 18 y from any country. Data sources included MEDLINE and Embase. All human epidemiological studies were included. Quality assessment excluded lowest-quality studies. Evidence synthesis by vote counting was depicted using harvest plots. A best available evidence approach was applied to narrative synthesis. The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement.

RESULTS

Of the 2,690 studies identified, 447 were screened in duplicate; of these, 117 underwent quality assessment, resulting in 46 included studies, of which 38 were included in vote counting (3 quasi-experimental, 1 cohort, 1 case control, and 33 cross-sectional studies). For the permanent dentition, findings were mixed; the balance of data showed no association between caries prevalence (7/11 studies) or severity (8/17 studies) with wasting. For the primary dentition, the balance of data showed a positive association between caries prevalence (10/15 studies) and severity (12/15 studies) with wasting, as well as between-caries prevalence (4/5 studies) and severity (6/6 studies) with stunting. Considering ECC only did not alter this pattern of findings.

CONCLUSION

The balance of evidence suggests that dental caries in the primary dentition is associated with undernutrition. There is a need for well-designed trials on the impact of caries rehabilitation on growth trajectories of children from low- and middle-income countries and for prospective studies of the impact of caries severity on both stunting and wasting to confirm causality.

KNOWLEDGE TRANSFER STATEMENT

The results of this study can be used by policy makers when considering the importance of oral health in addressing the United Nations Sustainable Development Goal to end all forms of malnutrition. The findings suggest that dental caries in the primary dentition may impair children's healthy weight gain. The findings indicate that higher-quality data are required to confirm a causal relationship and thus inform funding bodies of the need for research, especially in low- and middle-income countries, to substantiate the current knowledge and inform clear and accurate policy statements.

Bupropion does not antagonize cardiovascular actions of clonidine in normal subjects and spontaneously hypertensive rats

Tricyclic antidepressants (TADs) are known to antagonize the hypotensive and sedative actions of clonidine. We compared the effects of bupropion and imipramine pretreatment on the acute hypotensive and sedative actions of clonidine in eight normotensive male subjects in a randomized, double-blind crossover study. Pretreatment with bupropion, 100 mg by mouth three times a day for 9 days, had no effect on baseline supine blood pressure (BP) and heart rate (HR) and did not modify the hypotensive, bradycardic, and sedative actions of clonidine. Imipramine, 25 mg by mouth three times a day for 9 days, increased supine and standing HR and decreased standing systolic BP. In half the subjects the hypotensive action of clonidine was reduced 40% to 50% by imipramine. The specific binding of 3H-yohimbine to alpha 2-receptors of platelet membranes was not affected by pretreatment with either antidepressant. In spontaneously hypertensive rats, 16 days of bupropion, 25 mg/kg subcutaneously, had no effect on baseline BP and HR and did not antagonize the hypotensive and bradycardic effects of clonidine, 5 mg/kg iv. Pretreatment with desipramine, 5 mg/kg subcutaneously for 16 days, accelerated baseline HR and reduced cardiovascular actions of clonidine. These observations suggest that not all antidepressants antagonize the effects of clonidine. If the negative interaction between TADs and clonidine is a result of sensitivity of alpha 2-receptors, these receptor changes are not the common denominator of antidepressant activity and may only be seen with TADs.

Magnetic Field Stabilization for Magnetically Shielded Volumes by External Field Coils

For highly sensitive magnetic measurements, e.g., a measurement of the neutron electric dipole moment (EDM), the magnetic field has to be stable in time on a level below picoTesla. One of several measures we employ to achieve this uses an external field coil system which can stabilize the ambient external field at a predefined value. Here we report on the construction and characterization of such a system in the magnetic test facility at PSI. The system actively stabilizes the field along the axis of the EDM experiment by means of four coils in a Helmholtz-like configuration. Additional coils serve to compensate for transverse ambient field components. Because of the long integration times in the EDM experiment (about 100 s or more) only slow disturbances have to be corrected for. The performance of the system has been measured using static and moving magnetic sources and suppression factors in excess of 200 have been observed.

Elastic Isotropy in Martensitically Transforming FCC Alloys

The nature of the premartensitic state is still under debate. It is becoming evident that alloys which transform into a long period polymorph display the equivalent precursor strain modulations in the parent phases. The situation in alloys which transform in the center of the BZ is less clear, however. On the basis of electron microscopic [1,2,3] and X-ray diffraction data [4], it has been proposed for Fe-Pd alloy that the parent state consists of a coherent mixture of tetragonally distorted variants which may form a transitional phase. The interpretation is substantially based on the observation of 110 diffuse scattering and the softening of the elastic constant ½(C11 -C12) [1,2,5,6,7]. We have performed TEM studies of In-Tl alloys and investigated the low frequency mechanical response of In-Tl, In-Cd and Fe-Pd alloys. The phase diagrams of the three alloys [8,9,10], schematically presented in Fig. 1, show the common FCC-FCT martensitic transformation. Our studies indicate isotropic "elastic" softening and show that 111 streaking is present as well. This paper presents the mechanical results and their preliminary interpretation.

Notes from the field: interview with a perioperative trauma night nurse. Interview by Julie A. Meador

Trauma has significantly impacted our operating rooms with increases in care costs, staffing, and procedural needs. This article presents an interview with a frontline player in perioperative trauma, a night perioperative care coordinator. The coordinator provides a look into what it is like to plan, coordinate, and give perioperative trauma care on the night shift of a level I trauma center.

Prehospital severity scoring at major rock concert events

INTRODUCTION

Rock and contemporary music concerts are popular, recurrent events requiring on-site medical staffing.

STUDY OBJECTIVE

To describe a novel severity score used to stratify the level of acuity of patients presenting to first-aid stations at these events.

METHODS

Retrospective review of charts generated at the first-aid stations of five major rock concerts within a 60,000 spectator capacity, outdoor, professional sports stadium. Participants included all concert patrons presenting to the stadium's first-aid stations as patients. Data were collected on patient demographics, history of drug or ethanol usage while at the concert event, first-aid station time, treatment rendered, diagnosis, and disposition. All patients evaluated were retrospectively assigned a "DRUG-ROCK" Injury Severity Score (DRISS) to stratify their level of acuity. Individual concert events and patient dispositions were compared statistically using chi-square, Fisher's exact, and the ANOVA Mean tests.

RESULTS

Approximately 250,000 spectators attended the five concert events. First-aid stations evaluated 308 patients (utilization rate of 1.2 per 1,000 patrons). The most common diagnosis was minor trauma (130; 42%), followed in frequency by ethanol/illicit drug intoxication (98; 32%). The average time in the first-aid station was 23.5 +/- 22.5 minutes (+/- standard deviation; range: 5-150 minutes). Disposition of patients included 100 (32.5%) who were treated and released; 98 (32%) were transported by paramedics to emergency departments (EDs); and 110 (35.5%) signed-out against medical advise (AMA), refusing transport. The mean DRISS was 4.1 (+/- 2.65). Two-thirds (67%) of the study population were ranked as mild by DRISS criteria (score = 1-4), with 27% rated as moderate (score = 5-9), and 6% severe (score > 10). The average of severity scores was highest (6.5) for patients transported to hospitals, and statistically different from the scores of the average of the treated and released and AMA groups (p < 0.005).

CONCLUSION

The DRISS was useful in stratifying the acuity level of this patient population. This severity score may serve as a potential triage mechanism for future mass gatherings such as rock concerts.

Acne keloidalis in women

Acne keloidalis is a chronic scarring folliculitis that most commonly occurs on the scalps of young black men. This disorder is described in two black women who had no evidence of androgen excess. Trauma to scalp hair may have precipitated the condition in one patient. Although it is uncommon, acne keloidalis should be considered a treatable cause of cicatricial alopecia in women.

Humanization of a mouse antibody against human alpha-4 integrin: a potential therapeutic for the treatment of multiple sclerosis

alpha 4 beta 1 integrin (VLA-4) is crucial for the adhesion of leukocytes to human vascular cell adhesion molecule-1 (VCAM-1) on inflamed endothelium. This cell adhesion event is the first step in leukocyte extravasation across the blood-brain barrier in inflammatory diseases of the central nervous system (CNS) such as experimental autoimmune encephalomyelitis (EAE). Prevention of leukocyte infiltration by antibodies against the alpha 4 integrin, which block the alpha 4 beta 1 integrin/VCAM-1 interaction, have been shown to suppress clinical and pathological features of EAE. In this study, two mouse monoclonal antibodies (MAb) directed against human alpha 4 integrin were analyzed in vitro for their ability to block the interaction of leukocytes with VCAM-1 under different assay conditions. The best blocking MAb, AN100226m, was humanized by complementarily-determining region grafting, associated with human C regions and expressed. We found that modification of two structural determinants (H27 and H29) for the heavy chain CDR1 loop in one hand, and modification of framework amino acid H38, H40 and H44 in the other hand, had no effect on antigen binding. In contrast, modification of a structural determinant (H71) for the heavy chain CDR2 loop resulted in loss of binding. The humanized antibody. AN100226, was equivalent to the murine antibody. AN100226m, in binding to alpha 4 beta 1 integrin and in blocking cell adhesion. More importantly, AN100226 was as effective as AN100226m in the reversal of active EAE in guinea pigs and thus may be useful in the treatment of autoimmune diseases such as multiple sclerosis. AN100226 is currently in phase II clinical trials in the UK for the treatment of multiple sclerosis exacerbations.