Finding children with serious illness among the multitudes who present with fever is the number one challenge in paediatric emergency medicine.
A two year prospective cohort study was conducted at the Children’s Hospital Westmead in Sydney to develop and test a multivariable model to distinguish serious bacterial infections from self limiting non-bacterial illnesses.
A standardised clinical evaluation that included mandatory entry of 40 clinical features was recorded by physicians on around 15000 febrile kids under age 5. Clinical, laboratory and radiological follow up was undertaken to identify one of three key types of serious bacterial infection (SBI): urinary tract infection, pneumonia, and bacteraemia.
7.2% had SBI – urinary tract infection 3.4%, pneumonia 3.4%, and bacteraemia 0.4%.
A diagnostic model was developed using multinomial logistic regression methods. Physicians’ diagnoses of bacterial infection had low sensitivity (10-50%) and high specificity (90-100%), whereas the clinical diagnostic model provided a broad range of values for sensitivity and specificity.
The authors suggest that a computer assisted diagnostic decision tool could be used to determine the likelihood of serious bacterial infection.
The strongest positive predictors of serious bacterial infection were a generally very unwell appearance, high temperature, chronic disease, and prolonged capillary refill time. For children with pneumonia, other predictors were coughing, difficulty breathing, abnormal chest sounds, and to a lesser extent tachypnoea, chest crackles, and tachycardia. For urinary tract infection, the presence of urinary symptoms was by far the strongest indicator, whereas for bacteraemia, tachycardia and crying were also strong indicators although an editorial points out that only 64 cases of bacteraemia occurred, so this last result should be treated with caution.
The accuracy of clinical symptoms and signs for the diagnosis of serious bacterial infection in young febrile children: prospective cohort study of 15 781 febrile illnesses
BMJ. 2010 Apr 20;340:c1594
Tag Archives: clinical features
Atypical chest pain renders AMI more likely
A prospective study of 796 ED patients with suspected cardiac chest pain assessed the value of individual historical and examination findings for diagnosing acute myocardial infarction (AMI) and the occurrence of adverse events (death, AMI or urgent revascularization) within 6 months. AMI was diagnosed in 148 (18.6%) of the 796 patients recruited.
The results may surprise some physicians:
Sweating observed by the ED physician was the strongest predictor of AMI (adjusted OR 5.18, 95% CI 3.02–8.86).
Reported vomiting was also a fairly strong predictor of AMI (adjusted OR 3.50, 1.81–6.77).
Pain located in the left anterior chest was found to be the strongest negative predictor of AMI (adjusted OR 0.25, 0.14–0.46).
Patients who described the pain as being the same as previous myocardial ischaemia were significantly less likely to be having AMI!
Following adjustment for age, sex and ECG changes, the following characteristics made AMI more likely (adjusted odds ratio, 95% confidence intervals):
- pain radiating to the right arm (2.23, 1.24-4.00)
- pain radiating to both arms (2.69, 1.36-5.36)
- vomiting reported (3.50, 1.81-6.77), central chest pain (3.29, 1.94-5.61)
- sweating observed by physician (5.18, 3.02-8.86)
Pain in the left anterior chest made AMI significantly less likely (0.25, 0.14-0.46)
The presence of rest pain (0.67, 0.41-1.10) or pain radiating to the left arm (1.36, 0.89-2.09) did not significantly alter the probability of AMI.
Compare these results with the American Heart Association guidelines which state that “chest or left arm pain or discomfort as the chief symptom reproducing prior documented angina” is associated with a high likelihood of ACS, or the European Society of Cardiology guidelines which state that “the typical clinical presentation of NSTE-ACS is retrosternal pressure or heaviness radiating to the left arm, neck or jaw”, which the authors of this study point out are statements made based on expert opinion for which references are not given.
The authors summarise with a powerful message: ‘Several ‘atypical’ symptoms actually render AMI more likely, whereas many ‘typical’ symptoms that are often considered to identify high-risk populations have no diagnostic value.’
The value of symptoms and signs in the emergent diagnosis of acute coronary syndromes
Resuscitation. 2010 Mar;81(3):281-6
pain radiation to right arm in ACS
How predictive is the history for acute coronary syndrome? Of 1576 patients entered into a multicentre evaluation of chest pain units, 132 (8.4%) had ACS, as determined by positive troponin, CK-MB, or early treadmill test.
On multivariate analysis, only age, duration, sex and radiation of pain to the right arm were independently associated with ACS.
Likelihood ratios (95% CI) were:
- radiation of pain to the right arm, 2.9 (95% CI 1.4 to 6.3)
- male sex 1.2 (95% CI 1.0 to 1.3)
- female sex 0.79 (95% CI 0.62 to 1.0).
The area under the receiver operator characteristic curve for age was 0.629 (95% CI 0.573 to 0.686) and for duration was 0.546 (95% CI 0.481 to 0.610).
The authors conclude that clinical features have very limited value for diagnosing ACS in patients with a normal or non- diagnostic ECG, and radiation of pain to the right arm increases the likelihood of ACS.
Clinical diagnosis of acute coronary syndrome in patients with chest pain and a normal or non-diagnostic electrocardiogram.
Emerg Med J. 2009 Dec;26(12):866-70