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Overall costs of appendicitis diagnosis reduced by FACT
SCIENCE AND MEDICINE
Overall costs of appendicitis diagnosis reduced by FACT outine use of focused appendix computed tomography (FACT) to diagnose appendicitis improves patient care and reduces the use of hospital resources, according to a prospective study (N Engl J Med 1998; 338: 141–46).
SPL
R
Could this be the culprit?
On admission to Massachusetts General Hospital (Boston, MA, USA) for observation or emergency appendicectomy, the likelihood of appendicitis in 100 patients aged 6–75 was estimated by the referring
surgeon. Each patient then underwent FACT after colonic pretreatment with diatrizoate meglumine-saline solution. The scan took less than 15 minutes and the images were interpreted within 1 hour of the initial request. Diagnoses based on FACT had a sensitivity, specificity, positive and negative predictive values, and overall accuracy of 98%. Only three unnecessary operations were done when FACT and clinical findings were used for diagnosis, and no necessary operations were delayed. The use of FACT prevented 13 unnecessary appendicectomies, 18 unnecessary admissions for observation, 21 delays in having an appendicectomy, and accelerated the diagnosis of other conditions in 11 cases. Taking the cost of FACT into account, the authors claim an average saving of US$447 per patient. This saving would be reduced if FACT were used in the work-up of patients
Call for xenotransplantation moratorium eading scientists are calling for a moratorium on xenotransplantation until a number of ethical questions have been resolved and publicly constituted national advisory committees have been set up. Writing in Nature Medicine (1998; 4: 141–44), Fritz Bach (Harvard Medical School, Boston, MA, USA) and other US scientists say that the possibility that endogenous porcine retroviruses may transfer from the donor organ to the xenotransplant
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recipient raises a number of ethical problems. In particular, if the porcine viruses cause disease in human hosts, xenotransplantation, while being of potential benefit to the individual, may put the population at risk. The authors propose a moratorium on xenotransplantation in the public interest and were due to argue their case at a meeting in Washington, DC, USA, Jan 21–22.
ype A Sydney influenza— Australian flu—is making the rounds across the USA and may be responsible for nearly half the cases reported since the official flu season began in October, according to Stephen Ostroff of the National Center for Infectious Diseases, US Centers for Disease Control and Prevention (Atlanta, GA, USA). Type A Sydney is no more virulent than other flu strains, stresses Ostroff. “In any given flu season we will see about 20 000 deaths in the USA. This year some of those probably will be due to this variant, but that doesn’t make it special.” However, public-health officials are concerned that current flu vac-
THE LANCET • Vol 351 • January 24, 1998
Peter Moore
High flies may speed addiction research
cines, designed to protect against type A Wuhan virus, may not be as effective against type A Sydney virus, even though the viruses have the same subtype (H3N2). “People may be more likely to become ill if they contract this strain, even if they have been vaccinated”, says Ostroff. Nevertheless, the vaccine now in use should provide at least partial protection against type A Sydney, and Ostroff recommends its use in vulnerable patients, including the elderly and those with chronic illnesses, who are at high risk of developing secondary pneumonia after an episode of influenza.
ruit flies (Drosophila melanogaster) respond to “crack” cocaine very much like people do, says geneticist Jay Hirsh (University of Virginia, Charlottesville, VA, USA). “Genes that determine the nervous system, learning, and memory are all strongly conserved” between the species, he notes, so studying flies could help unravel the molecular basis of human cocaine addiction. Hirsh and Colleen McClung exposed flies to vapourised “crack” cocaine and videotaped their responses. Low doses led to “intense grooming”; higher doses caused rapid twirling, sideways or backwards locomotion, bouncing off the wall of their containers, and ultimately, tremors, paralysis, or death. During recovery, the flies displayed the same behaviours in reverse order. Repeated, intermittent exposure to the drug led to more severe behaviours in response to lower doses. Such “reverse tolerance” also occurs in people, says Hirsh, and may underlie the paranoia and psychosis seen in cocaine addicts (Curr Biol 1998; 8: 109–12). The Virginia team are now making fly mutants, using cocaine as a discriminative factor in order to study the biology of addiction.
Norra Macready
Marilynn Larkin
Jane Bradbury
New flu strain nothing to sneeze at
T
where there was only a low suspicion of appendicitis. However, increased accuracy in diagnosing appendicitis would be beneficial to the physician as well as the patient because in the USA misdiagnosis is the most frequent cause of successful malpractice claims made against emergencydepartment physicians. Radiologist Adrian Dixon (University of Cambridge, UK) says that FACT is unlikely to be used extensively in the UK for some time. “Most of our CT systems are fully booked, by contrast to the USA where the greater availability of magnetic resonance imaging has left some CT systems underused.” However, Dixon adds that a reference to FACT may be included in Royal College of Radiologists’ guidelines to be issued later this year. At present, the guidelines recommend graded ultrasonography for diagnosis of equivocal cases.
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271
Overall costs of appendicitis diagnosis reduced by FACT outine use of focused appendix computed tomography (FACT) to diagnose appendicitis improves patient care and reduces the use of hospital resources, according to a prospective study (N Engl J Med 1998; 338: 141–46).
SPL
R
Could this be the culprit?
On admission to Massachusetts General Hospital (Boston, MA, USA) for observation or emergency appendicectomy, the likelihood of appendicitis in 100 patients aged 6–75 was estimated by the referring
surgeon. Each patient then underwent FACT after colonic pretreatment with diatrizoate meglumine-saline solution. The scan took less than 15 minutes and the images were interpreted within 1 hour of the initial request. Diagnoses based on FACT had a sensitivity, specificity, positive and negative predictive values, and overall accuracy of 98%. Only three unnecessary operations were done when FACT and clinical findings were used for diagnosis, and no necessary operations were delayed. The use of FACT prevented 13 unnecessary appendicectomies, 18 unnecessary admissions for observation, 21 delays in having an appendicectomy, and accelerated the diagnosis of other conditions in 11 cases. Taking the cost of FACT into account, the authors claim an average saving of US$447 per patient. This saving would be reduced if FACT were used in the work-up of patients
Call for xenotransplantation moratorium eading scientists are calling for a moratorium on xenotransplantation until a number of ethical questions have been resolved and publicly constituted national advisory committees have been set up. Writing in Nature Medicine (1998; 4: 141–44), Fritz Bach (Harvard Medical School, Boston, MA, USA) and other US scientists say that the possibility that endogenous porcine retroviruses may transfer from the donor organ to the xenotransplant
L
recipient raises a number of ethical problems. In particular, if the porcine viruses cause disease in human hosts, xenotransplantation, while being of potential benefit to the individual, may put the population at risk. The authors propose a moratorium on xenotransplantation in the public interest and were due to argue their case at a meeting in Washington, DC, USA, Jan 21–22.
ype A Sydney influenza— Australian flu—is making the rounds across the USA and may be responsible for nearly half the cases reported since the official flu season began in October, according to Stephen Ostroff of the National Center for Infectious Diseases, US Centers for Disease Control and Prevention (Atlanta, GA, USA). Type A Sydney is no more virulent than other flu strains, stresses Ostroff. “In any given flu season we will see about 20 000 deaths in the USA. This year some of those probably will be due to this variant, but that doesn’t make it special.” However, public-health officials are concerned that current flu vac-
THE LANCET • Vol 351 • January 24, 1998
Peter Moore
High flies may speed addiction research
cines, designed to protect against type A Wuhan virus, may not be as effective against type A Sydney virus, even though the viruses have the same subtype (H3N2). “People may be more likely to become ill if they contract this strain, even if they have been vaccinated”, says Ostroff. Nevertheless, the vaccine now in use should provide at least partial protection against type A Sydney, and Ostroff recommends its use in vulnerable patients, including the elderly and those with chronic illnesses, who are at high risk of developing secondary pneumonia after an episode of influenza.
ruit flies (Drosophila melanogaster) respond to “crack” cocaine very much like people do, says geneticist Jay Hirsh (University of Virginia, Charlottesville, VA, USA). “Genes that determine the nervous system, learning, and memory are all strongly conserved” between the species, he notes, so studying flies could help unravel the molecular basis of human cocaine addiction. Hirsh and Colleen McClung exposed flies to vapourised “crack” cocaine and videotaped their responses. Low doses led to “intense grooming”; higher doses caused rapid twirling, sideways or backwards locomotion, bouncing off the wall of their containers, and ultimately, tremors, paralysis, or death. During recovery, the flies displayed the same behaviours in reverse order. Repeated, intermittent exposure to the drug led to more severe behaviours in response to lower doses. Such “reverse tolerance” also occurs in people, says Hirsh, and may underlie the paranoia and psychosis seen in cocaine addicts (Curr Biol 1998; 8: 109–12). The Virginia team are now making fly mutants, using cocaine as a discriminative factor in order to study the biology of addiction.
Norra Macready
Marilynn Larkin
Jane Bradbury
New flu strain nothing to sneeze at
T
where there was only a low suspicion of appendicitis. However, increased accuracy in diagnosing appendicitis would be beneficial to the physician as well as the patient because in the USA misdiagnosis is the most frequent cause of successful malpractice claims made against emergencydepartment physicians. Radiologist Adrian Dixon (University of Cambridge, UK) says that FACT is unlikely to be used extensively in the UK for some time. “Most of our CT systems are fully booked, by contrast to the USA where the greater availability of magnetic resonance imaging has left some CT systems underused.” However, Dixon adds that a reference to FACT may be included in Royal College of Radiologists’ guidelines to be issued later this year. At present, the guidelines recommend graded ultrasonography for diagnosis of equivocal cases.
F
271