Category: Prior Clinic Blog
Blood Transfusion May Transmit Variant CJD
July 10th, 2003 , by adminSTUDY:
JOURNAL: Lancet. 2004;363:411-412, 417-421, 422-428
AUTHORS: Robert G. Will
ABSTRACT: — Blood transfusion may be a mode of transmitting variant Creutzfeldt-Jakob disease (vCJD).
COMMENTARY: On Dec. 17, 2003, the U.K. announced the death from vCJD of an individual who had previously received a red cell transfusion from a donor who subsequently developed vCJD. Symptoms of vCJD developed in the recipient 6.5 years after the transfusion, and in the donor 3.5 years after the transfusion.
Using the national blood-donor database and the U.K. CJD register, a team from the National CJD Surveillance Unit of Western General Hospital in Edinburgh, U.K., identified 48 individuals, including the subject of the case report, who received a blood component from 15 donors who later developed vCJD.
"Our findings raise the possibility that this infection was transfusion transmitted," senior author Robert G. Will says in a news release. "Infection in the recipient could have been due to past dietary exposure to the BSE [bovine spongiform encephalopathy] agent.
The clinical presentation and preliminary examination of neuropathology of this patient were typical of vCJD. Although magnetic resonance imaging did not show the classical pulvinar sign seen in most cases of vCJD, fluid attenuated inversion recovery sequences with the highest sensitivity were not obtained.
The red blood cells transfused in this patient were not leucodepleted, but the authors note that the efficiency of leucodepletion in reducing infectivity is uncertain.
The surviving recipients of blood transfusions from donors who later developed vCJD are being informed of their possible increased risk of developing vCJD and warned not to donate organs or blood.
"To date, no case of vCJD has been identified with a history of exposure to fractionated blood products," the authors write. "The most direct action to reduce risk is a careful case-by-case evaluation of the need for blood transfusion."
The National Blood Service supported this study.
In an animal study in the same issue of The Lancet, Corinne Lasmézas and colleagues, from the French Atomic Energy Commission, compared the degree of tissue infectivity among macaques with oral or intravenous exposure to tissue containing the BSE agent.
Using the misfolded prion protein as a marker, they found that the degree of organ infectivity was similar regardless of the route of entry, and that tonsil tissue was the most strongly infected. In addition to expected concentrations of prion protein in the brain and spinal cord, it was also present in the autonomic nervous system, in peripheral nerves, and in Peyer's patches in the gut, suggesting possible risk of transmission from endoscopic procedures.
"In view of the high efficiency of transmission of the BSE agent to primates by the intravenous route, the latter should be regarded as a likely route of contamination for vCJD patients with a medical history involving a transfusion during the period at risk," the authors write.
"To avoid further contamination to human beings from peripheral tissues, the same precautionary measures taken for primary vCJD cases should apply to possible transfusion cases of the disease."
Probiotics Well Tolerated, Safe in Infant Formula
July 9th, 2003 , by adminSTUDY:
JOURNAL: Am J Clin Nutr. 2004;79:261-267
AUTHORS: Jose M. Saavedra
ABSTRACT: Probiotic-supplemented infant formula is well tolerated and safe, according to the results of a randomized, double-blind, placebo-controlled trial published in the February issue of the American Journal of Clinical Nutrition.
Furthermore, treated infants had a lower rate of colic and use of antibiotics.
COMMENTARY: "Nonpathogenic live bacteria are consumed as food by many children, particularly in the form of yogurt," write Jose M. Saavedra, from the Johns Hopkins University School of Medicine in Baltimore, Maryland, and colleagues.
"The tolerance and safety of long-term consumption of specific types and strains of probiotic bacteria are not well documented.... Adequate documentation of safety with prolonged use in infants is mandatory if recommendations for use are to be made in this population."
In this prospective study, 118 healthy infants aged three to 24 months were randomized to receive one of three standard milk-based formulas: formula containing 1 x 107 colony-forming units (CFU)/g each of Bifidobacterium lactis and Streptococcus thermophilus, formula containing 1 x 106 CFU/g each of B. lactis and S. thermophilus, or unsupplemented formula.
At enrollment, mean age was 7.0 ± 2.9 months; the groups were similar in age, sex, and duration of formula consumption (mean, 210 ± 127 days). Compared with the unsupplemented formula, the supplemented formulas were well accepted and were associated with a lower frequency of reported colic or irritability (P < .001) and of antibiotic use (P < .001).
Growth, utilization of healthcare services, daycare absenteeism, and other health variables were similar between groups.
"To our knowledge, this is the first careful documentation of intake of live bacteria over any extended period of time in any population. The intakes studied can be used as a benchmark for well-tolerated, safe intake of these bacterial agents," the authors write.
"Long-term consumption of formulas supplemented with B. lactis and S. thermophilus was well tolerated and safe and resulted in adequate growth, reduced reporting of colic or irritability, and a lower frequency of antibiotic use."
Nestlé USA supported this study and provided formulas.
Sweet Potato Extract Improves Glycemic Control in Type 2 Diabetes
July 8th, 2003 , by adminSTUDY:
JOURNAL: Diabetes Care. 2004;27:436-440
AUTHORS: Dr. Ludvik
ABSTRACT: Caiapo has beneficial effects on the plasma glucose and cholesterol levels of patients with type 2 diabetes, according to the results of a randomized, double-blind, placebo-controlled trial.
COMMENTARY: Caiapo is a nutraceutical made from the extract of a variety of white sweet potato (Ipomoea batatas) that has been eaten raw in Japan for treatment of anemia, hypertension, and diabetes.
Bernhard Ludvik, MD, and colleagues from the University of Vienna in Austria selected 61 clinically stable type 2 diabetic patients. Subjects discontinued antidiabetic medication and followed a weight-maintaining diet (28-32 kcal/kg of body weight) consisting of 55% carbohydrates, 30% fat, and 15% proteins.
Patients were allowed to continue drinking alcohol and smoking cigarettes, although in limited amounts. Investigators advised subjects to maintain usual physical activity at a constant level throughout the study period.
The researchers divided patients into two groups: group 1 (n = 30) consumed Caiapo 4 g/day, and group 2 (n = 31) consumed placebo. Patients took Caiapo or placebo orally once daily, in the morning before breakfast. Data from both groups showed no differences at baseline except for glucose levels measured two hours after dinner.
The investigators administered a 75 g oral glucose tolerance test (OGTT) at baseline and after one, two, and three months. Fasting and two-hour glucose levels were measured from venous samples by the glucose oxidase method. Patients measured their blood glucose levels at home using a blood glucose test system three times per week: Monday before breakfast, Wednesday two hours after beginning lunch, and Friday two hours after beginning dinner. The investigators also measured HbA1c, cholesterol, and triglyceride levels.
After months 2 and 3, HbA1c levels significantly decreased in the Caiapo group (from 7.21% ± 0.15% at baseline to 6.94% ± 0.14% at two months and 6.68% ± 0.14% at three months; P < .05) compared with no change in the placebo group (P = .08 after two months and P = .23 after three months). At months 2 and 3, HbA1c values in the Caiapo group were lower than those in the placebo group (P < .0001).
Fasting blood glucose levels decreased in the Caiapo group (143.7 ± 1.9 mg/dL vs. 128.5 ± 1.7 mg/dL; P < .001) and did not change in the placebo group (144.3 ± 1.9 mg/dL vs. 138.2 ± 2.1 mg/dL; P = .052). The investigators observed a decrease in body weight in both the placebo group (P = .0027) and in the Caiapo group (P < .0001).
Body weight was linked to improvement in glucose control in the Caiapo group (r = 0.618; P < .0002). Two-hour glucose levels decreased significantly in the Caiapo group (193.3 ± 10.4 mg/dL vs. 162.8 ± 8.2 mg/dL) compared with the placebo group (191.7 ± 9.2 mg/dL vs. 181.0 ± 7.1 mg/dL; P < .001).
The investigators also found significantly lower levels of mean cholesterol in the Caiapo group at the end of treatment (214.6 ± 11.2 mg/dL) than in the placebo group (248.7 ± 11.2 mg/dL; P < .05). They did not observe significant changes in triglyceride levels or blood pressure. Caiapo was well tolerated without significant adverse effects.
"This study confirms the beneficial effects of Caiapo on fasting and postprandial plasma glucose levels, as well as on cholesterol, in patients with type 2 diabetes," they write. "For the first time, we demonstrated the long-term efficacy of Caiapo on glucose control by the observed reduction of HbA1c."
Low-Dose Infant Radiation May Affect Adult Intellect
July 7th, 2003 , by adminSTUDY:
JOURNAL: BMJ. 2004;328:19-21
AUTHORS: Per Hall
ABSTRACT: Infants exposed to doses of ionizing radiation equivalent to a computed tomography (CT) scan have lower cognitive abilities as adults.
COMMENTARY: "Ionising radiation may impair the developing human brain and adversely affect cognitive processes," write Per Hall, from Karolinska Institute in Stockholm, Sweden, and colleagues. "CT scanning, which delivers high doses of ionising radiation, is increasingly being used in young children after minor head trauma."
The study cohort consisted of 3,094 men who had received radiation therapy during the period from 1930 to 1959, before they were 18 months of age. At age 18 or 19 years, psychological testing revealed a negative dose-response relationship for three cognitive tests for learning ability and logical reasoning, but not for spatial recognition.
The proportion of boys who attended high school decreased with increasing doses of ionizing radiation to both frontal and posterior brain regions, from 32% for no radiation exposure to 17% for exposure greater than 250 mGy. With frontal radiation, the multivariate odds ratio for high school attendance was 0.47 (95% confidence interval [CI], 0.26 - 0.85; P = .0003 for trend), and with posterior radiation it was 0.59 (95% CI, 0.23 - 1.47; P = .0005).
"Irradiation of the brain with dose levels overlapping those imparted by CT can, in at least some instances, adversely affect intellectual development when the infant brain is exposed to ionising radiation at doses equivalent to CT scans of the skull," the authors write. "The risk and benefits of CT scans in minor head trauma need re-evaluating."
The European Commission supported this study, and the authors report no conflicts of interest.
Manual Therapy Best for Neck Pain
July 5th, 2003 , by adminSTUDY:
JOURNAL: BMJ. 2003;326:911-914
AUTHORS: Ingeborg Korthals-de Bos
ABSTRACT: Manual therapy is more effective than traditional physiotherapy or general medical care for the treatment of neck pain.
COMMENTARY: "Our findings showed manual therapy to be more cost effective than physiotherapy and continued care provided by a general practitioner in the treatment of nonspecific neck pain," write Ingeborg Korthals-de Bos, from VU University Medical Centre in Amsterdam, the Netherlands, and colleagues.
A total of 183 patients with neck pain for at least two weeks were recruited by 42 general practitioners in the Netherlands. Age range was 18 to 70 years. Of the 183 subjects, 60 were randomized to manual therapy consisting of spinal mobilization, 59 to physiotherapy consisting mainly of exercise, and 64 to standard care from a general practitioner, including counseling, education, and medications. "Spinal mobilization was defined as low velocity passive movements within or at the limit of joint range of motion. Spinal manipulation (low amplitude, high velocity techniques) was not provided," according to the authors.
After 26 weeks, patients in the manual therapy group recovered more quickly than did patients in the other two groups. By 52 weeks, there were no significant differences between groups. The total average costs of manual therapy were $402, about one third of the costs in the other two groups (P < .01).
"Manual therapy had significantly lower costs and slightly better effects in treating neck pain at 52 weeks compared with physiotherapy and general practitioner care," the authors write. "The clinical outcome measures showed that manual therapy resulted in faster recovery."

