Diagnosis of pulmonary embolism
Few common conditions are surrounded by as much clinical uncertainty and diagnostic mystery as pulmonary embolism. It may be silent, or it may be fatal, and clinicians are rightfully wary of its nonspecific symptoms. With the increasing availability of D-dimer testing and more advanced imaging, the capacity for noninvasive diagnosis has increased. Unfortunately, so has the complexity of possible combinations of tests. In this scholarly review, Clive Kearon summarizes the evidence for diagnosis of pulmonary embolism, focusing on sensitivity, specificity and the predictive values of available tools, both in isolation and in combination. A comprehensive algorithm is given to help the investigating physician navigate his or her patient through the many tests.
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Heroin seizure and overdose rates
Nearly 95% of the money assigned to combatting illegal drugs in Canada is dedicated to reducing supply. In September 2000, Canadian police intercepted 100 kg of heroin in Vancouver, reportedly the largest seizure in Canadian history. At the time, it was suggested that the removal of this quantity of heroin would limit supply, push prices beyond the range of youth at high risk of experimentation and perhaps decrease the overdose rate. Evan Wood and colleagues put that hypothesis to the test by looking at a large cohort of injection drug users who were seen during the 30-day periods before and after the seizure and comparing the 2 groups. No differences in use patterns or heroin availability were seen after the seizure, and the price actually dropped. External evaluations of deaths and of heroin purity showed no impact from the seizure. The authors question the public health benefit of the seizure and suggest that some money might be diverted to areas with proven harm reduction.
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Hypereosinophilic syndrome in a patient with asthma
Idiopathic hypereosinophilia often causes multiple organ dysfunction. In this case report, a 50-year-old woman with bronchial asthma was admitted to hospital for a refractory exacerbation of cough, chest tightness and wheezing. Incidental note of elevated eosinophil counts had been made during 3 similar previous admissions, but no further investigations were done. During the current admission, the patient showed evidence of both pulmonary and cardiac involvement in the face of a persistently elevated eosinophil count. Demet Karnak and coworkers discuss the details of this interesting case and the subsequent diagnosis and management of hypereosinophilic syndrome.
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Shaken baby syndrome in Canada
An extremely serious form of abuse, shaken baby syndrome occurs when a child is subjected to dangerous forces of acceleration, deceleration and torsion, causing a unique constellation of cerebral, ocular and cervical injuries. The outcome is devastating, with up to 27; of children dying, and survivors often requiring long-term care. Much of this is known from small populations of injured children in the US and UK. James King and colleagues performed a retrospective chart review of cases reported during a 10-year period at 11 tertiary pediatric hospitals across Canada. Nearly 20% of the children died, 55% had lasting neurologic injury and 65% had visual impairment. The median age of subjects was 4.6 months.
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Screening for colorectal cancer
Colorectal cancer is common, its history is well understood and, if started early, its treatment is highly effective. Furthermore, it may be detected using a cost-effective screening test that is easily accepted by patients and has been proven to reduce mortality. With the recent endorsement of fecal occult blood (FOB) screening by 2 national bodies, Richard Schabas argues that we have already waited too long to implement a coordinated approach using FOB screening. It is evidence-based, feasible and saves lives.
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