Daniel van Hoving

Prof. Daniel van Hoving

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Research Focus & Metrics

Academic Career Length

19Years (2008-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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9 September 2020 in npj Digital Medicine
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PRPranav Rajpurkar
Pranav Rajpurkar
COChloe O’connell
Chloe O’connell
ASAmit Schechter
Amit Schechter
NANishit Asnani
Nishit Asnani
JLJason Li
Jason Li
MLMatthew P. Lungren
Matthew P. Lungren
Tuberculosis (TB) is the leading cause of preventable death in HIV-positive patients, and yet often remains undiagnosed and untreated. Chest x-ray is often used to assist in diagnosis, yet this presents additional challenges due to atypical radiographic presentation and radiologist shortages in regions where co-infection is most common. We developed a deep learning algorithm to diagnose TB using clinical information and chest x-ray images from 677 HIV-positive patients with suspected TB from two hospitals in South Africa. We then sought to determine whether the algorithm could assist clinicians in the diagnosis of TB in HIV-positive patients as a web-based diagnostic assistant. Use of the algorithm resulted in a modest but statistically significant improvement in clinician accuracy (p = 0.002), increasing the mean clinician accuracy from 0.60 (95% CI 0.57, 0.63) without assistance to 0.65 (95% CI 0.60, 0.70) with assistance. However, the accuracy of assisted clinicians was significantly lower (p < 0.001) than that of the stand-alone algorithm, which had an accuracy of 0.79 (95% CI 0.77, 0.82) on the same unseen test cases. These results suggest that deep learning assistance may improve clinician accuracy in TB diagnosis using chest x-rays, which would be valuable in settings with a high burden of HIV/TB co-infection. Moreover, the high accuracy of the stand-alone algorithm suggests a potential value particularly in settings with a scarcity of radiological expertise.

28 June 2010 in Prehospital and Disaster Medicine
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DHDaniel van Hoving
Daniel van Hoving
LWLee Wallis
Lee Wallis
FDFathima Docrat
Fathima Docrat
SVShaheem De Vries
Shaheem De Vries
The devastating Haiti earthquake rightly resulted in an outpouring of international aid. Relief teams can be of tremendous value during disasters due to natural hazards. Although nobly motivated to help, all emergency interventions have unintended consequences. In the immediate aftermath of the earthquake, many selfless individuals committed to help, but was this really all in the name of reaching out a helping hand? This case report illustrates that medical disaster tourism is alive and well.

30 September 2019 in Cochrane Database of Systematic Reviews
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Journal Article
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DHDaniel van Hoving
Daniel van Hoving
RGRulan Griesel
Rulan Griesel
GMGraeme Meintjes
Graeme Meintjes
YTYemisi Takwoingi
Yemisi Takwoingi
GMGary Maartens
Gary Maartens
EOEleanor A Ochodo
Eleanor A Ochodo
Background Accurate diagnosis of tuberculosis in people living with HIV is difficult. HIV‐positive individuals have higher rates of extrapulmonary tuberculosis and the diagnosis of tuberculosis is often limited to imaging results. Ultrasound is such an imaging test that is widely used as a diagnostic tool (including point‐of‐care) in people suspected of having abdominal tuberculosis or disseminated tuberculosis with abdominal involvement. Objectives To determine the diagnostic accuracy of abdominal ultrasound for detecting abdominal tuberculosis or disseminated tuberculosis with abdominal involvement in HIV‐positive individuals. To investigate potential sources of heterogeneity in test accuracy, including clinical setting, ultrasound training level, and type of reference standard. Search methods We searched for publications in any language up to 4 April 2019 in the following databases: MEDLINE, Embase, BIOSIS, Science Citation Index Expanded (SCI‐EXPANDED), Social Sciences Citation Index (SSCI), Conference Proceedings Citation Index‐ Science (CPCI‐S), and also ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform to identify ongoing trials. Selection criteria We included cross‐sectional, cohort, and diagnostic case‐control studies (prospective and retrospective) that compared the result of the index test (abdominal ultrasound) with one of the reference standards. We only included studies that allowed for extraction of numbers of true positives (TPs), true negatives (TNs), false positives (FPs), and false negatives (FNs). Participants were HIV‐positive individuals aged 15 years and older. A higher‐quality reference standard was the bacteriological confirmation of Mycobacterium tuberculosis from any clinical specimen, and a lower‐quality reference standard was a clinical diagnosis of tuberculosis without microbiological confirmation. We excluded genitourinary tuberculosis. Data collection and analysis For each study, two review authors independently extracted data using a standardized form. We assessed the quality of studies using a tailored Quality Assessment of Diagnostic Accuracy Studies‐2 (QUADAS‐2) tool. We used the bivariate model to estimate pooled sensitivity and specificity. When studies were few we simplified the bivariate model to separate univariate random‐effects logistic regression models for sensitivity and specificity. We explored the influence of the type of reference standard on the accuracy estimates by conducting separate analyses for each type of reference standard. We assessed the certainty of the evidence using the GRADE approach. Main results We included 11 studies. The risks of bias and concern about applicability were often high or unclear in all domains. We included six studies in the main analyses of any abnormal finding on abdominal ultrasound; five studies reported only individual lesions. The six studies of any abnormal finding were cross‐sectional or cohort studies. Five of these (83%) were conducted in low‐ or middle‐income countries, and one in a high‐income country. The proportion of participants on antiretroviral therapy was none (1 study), fewer then 50% (4 studies), more than 50% (1 study), and not reported (5 studies). The first main analysis, studies using a higher‐quality reference standard (bacteriological confirmation), had a pooled sensitivity of 63% (95% confidence interval (CI) 43% to 79%; 5 studies, 368 participants; very low‐certainty evidence) and a pooled specificity of 68% (95% CI 42% to 87%; 5 studies, 511 participants; very low‐certainty evidence). If the results were to be applied to a hypothetical cohort of 1000 people with HIV where 200 (20%) have tuberculosis then: ‐ About 382 individuals would have an ultrasound result indicating tuberculosis; of these, 256 (67%) would be incorrectly classified as having tuberculosis (false positives). ‐ Of the 618 individuals with a result indicating that tuberculosis is not present, 74 (12%) would be incorrectly classified as not having tuberculosis (false negatives). In the second main analysis involving studies using a lower‐quality reference standard (clinical diagnosis), the pooled sensitivity was 68% (95% CI 45% to 85%; 4 studies, 195 participants; very low‐certainty evidence) and the pooled specificity was 73% (95% CI 41% to 91%; 4 studies, 202 participants; very low‐certainty evidence). Authors' conclusions In HIV‐positive individuals thought to have abdominal tuberculosis or disseminated tuberculosis with abdominal involvement, abdominal ultrasound appears to have 63% sensitivity and 68% specificity when tuberculosis was bacteriologically confirmed. These estimates are based on data that is limited, varied, and low‐certainty. The low sensitivity of abdominal ultrasound means clinicians should not use a negative test result to rule out the disease, but rather consider the result in combination with other diagnostic strategies (including clinical signs, chest x‐ray, lateral flow urine lipoarabinomannan assay (LF‐LAM), and Xpert MTB/RIF). Research incorporating the test into tuberculosis diagnostic algorithms will help in delineating more precisely its value in diagnosing abdominal tuberculosis or disseminated tuberculosis with abdominal involvement.

16 May 2012 in Emergency Medicine Journal
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DHDaniel van Hoving
Daniel van Hoving
HLHeinrich H Lamprecht
Heinrich H Lamprecht
MSMelanie Stander
Melanie Stander
KVKamil Vallabh
Kamil Vallabh
DFDavid Fredericks
David Fredericks
JMJacques J Malan
Jacques J Malan
Objective This prospective cross-sectional study assesses the adequacy of the current South African emergency point-of-care ultrasound (EPCUS) core curriculum against the local burden of disease. Method Patients presenting to five Emergency Centres during July 2011 were eligible for inclusion. Patients under the age of 12, after-hour presentations, missing folders and folders with incomplete notes were excluded. Emergency physicians with EPCUS exposure were responsible for data collection. They were all blinded to the study's aim. Summary statistics describe the proportion of clinical cases and procedures for which EPCUS was used. One investigator assessed the adequacy of the curriculum by matching the clinical indications of each module with the presenting complaint and final diagnosis of each patient. The ultrasound modules were ranked according to the frequency of their clinical indications. κ-Statistics are reported on 10% randomly selected cases to quantify interobserver agreement. Results The study included 2971 patients. Ultrasound assisted with diagnosis in 384 (12.92%) patients and in 34 (1.14%) procedures. A total of 1933 EPCUS procedures were indicated in 1844 (66.07%) patients. The five most frequently indicated modules were pulmonary, musculoskeletal, cardiac, focused assessment with sonography of HIV/tuberculosis co-infection and renal. The interobserver agreement (κ) was 0.602 (95% CI 0.559 to 0.645). Conclusions This study was an attempt to ensure an evidence-based approach to assess the adequacy of the EPCUS core curriculum in South Africa. The results illustrate that our local burden of disease may require a change of the current core curriculum.

1 June 2011 in African Journal of Emergency Medicine
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Journal Article
Open access
DHDaniel van Hoving
Daniel van Hoving
DVD.J.H. Veale
D.J.H. Veale
GMG.F. Müller
G.F. Müller
Acutely poisoned patients are commonly encountered in Emergency Centres. Acute poisoning (accidental or intentional) requires accurate assessment and prompt therapy. The necessity to prevent cross contamination during the initial evaluation should be emphasized. Early identification of the involved toxin/s is crucial and the majority will be identified by a thorough history and physical examination. An ABC-approach should be followed ensuring a protected airway, adequate ventilation and hemodynamic stability. Supportive and symptomatic care remains the cornerstone of treatment. A stepwise approach may be followed to decrease the bioavailability of toxins. Indications, contra-indications, risks and dosage regimens are describe for decontamination procedures including both termination of topical exposures and decreasing exposure to ingested toxins. Furthermore, procedures to increase the elimination of toxins and a short section covering specific toxins and their antidotes are also included. The aim of this commissioned review was to establish concise guidelines for the initial management of the acutely poisoned patient in the Emergency Centre. The American Academy of Clinical Toxicology and the European Association of Poisons Centres and Clinical Toxicologists are the international leaders in the field of toxicology and the guidelines in their position papers were generally followed. Most of the dosage regimes are according to the South African Medicines Formulary. © 2011 African Federation for Emergency Medicine.Revie

1 September 2018 in African Journal of Emergency Medicine
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Journal Article
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DHDaniel van Hoving
Daniel van Hoving
LHLuke D. Hunter
Luke D. Hunter
RGRachel (Elre) J. Gerber
Rachel (Elre) J. Gerber
HLHendrick J. Lategan
Hendrick J. Lategan
CMCarine J. Marks
Carine J. Marks
Intentional self-poisoning is a significant part of the toxicological burden experienced by emergency centres. The aim of this study was to describe all adults presenting with intentional self-poisoning over a six-month period to the resuscitation unit of Khayelitsha Hospital, Cape Town. Adult patients with a diagnosis of intentional self-poisoning between 1 November 2014 and 30 April 2015 were retrospectively analysed after eligible patients were obtained from the Khayelitsha Hospital Emergency Centre database. Missing data and variables not initially captured in the database were retrospectively collected by means of a chart review. Summary statistics were used to describe all variables. A total of 192 patients were included in the analysis. The mean age was 27.3 years with the majority being female (n = 132, 68.8%). HIV-infection was a comorbidity in 39 (20.3%) patients, while 13 (6.8%) previously attempted suicide. Presentations per day of the week were almost equally distributed while most patients presented after conventional office hours (n = 152, 79.2%), were transported from home (n = 124, 64.6%) and arrived by ambulance (n = 126, 65.6%). Patients spend a median time of 3h37m in the resuscitation unit (interquartile range 1 h 45 m-7 h 00 m; maximum 65 h 49 m). Patient acuity on admission was mostly low according to both the Triage Early Warning Score (non-urgent n = 100, 52.1%) and the Poison Severity Score (minor severity n = 107, 55.7%). Pharmaceuticals were the most common type of toxin ingested (261/343, 76.1%), with paracetamol the most frequently ingested toxin (n = 48, 25.0%). Eleven patients (5.7%) were intubated, 27 (14.1%) received N-acetylcysteine, and 18 (9.4%) received benzodiazepines. Fourteen (7.3%) patients were transferred to a higher level of care and four deaths (2%) were reported. Intentional self-poisoning patients place a significant burden on emergency centres. The high percentage of low-grade acuity patients managed in a high-acuity area is of concern and should be investigated further.