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The widespread use of wireless telecommunications devices, particularly mobile phones, has resulted in increased human exposure to radiofrequency (RF) fields. Although national and international agencies have established safety guidelines for exposure to RF fields, concerns remain about the potential for adverse health outcomes to occur in relation to RF field exposure. The extensive literature on RF fields and health has been reviewed by a number of authorities, including the Royal Society of Canada (1999), the European Commission's Scientific Committee on Toxicity, Ecotoxicity, and the Environment (CSTEE, 2001), the British Medical Association (2001), the Swedish Radiation Protection Authority (Boice & McLaughlin, 2002), and the Health Council of The Netherlands (2002). This report provides an update on recent research results on the potential health risks of RF fields since the publication of the Royal Society of Canada report in 1999 (See Krewski et al., 2001a) and our previous 2001 update (Krewski et al., 2001b), covering the period 2001-2003. The present report examines new data on dosimetry and exposure assessment, biological effects such as enzyme induction, and toxicological effects, including genotoxicity, carcinogenicity, and testicular and reproductive outcomes. Epidemiological studies of mobile phone users and occupationally exposed populations are examined, along with human and animal studies of neurological and behavioral effects. All of the authoritative reviews completed within the last 2 yr have concluded that there is no clear evidence of adverse health effects associated with RF fields. However, following a recent review of nine epidemiological studies of mobile phones and cancer, Kundi et al. (2004) concluded that the possibility of an enhanced cancer risk cannot be excluded. These same reviews support the need for further research to clarify the possible associations between RF fields and adverse health outcomes that have appeared in some reports. The results of the ongoing World Health Organization (WHO) study of mobile phones will provide important new information in this regard.

Objective: To determine if aerially spraying a biological pesticide was associated with an increase in the symptoms or change in the Peak Expiratory Flow Rate of children with asthma., Methods: A pre/post matched pairs cohort design was used. Children living in the spray zone were matched with children outside of the spray zone. Peak Expiratory Flow Rates, asthma symptoms and non-asthma symptoms were recorded in diaries., Results: There were no differences in asthma symptom scores between subjects and controls, neither before nor after the spray; nor were there significant changes in Peak Expiratory Flow Rates for subjects after the spray period., Conclusions: No evidence of adverse effects from the use of the biological pesticide was found. We believe that this is the first paper to address the issue of whether or not aerial spraying with Btk has a harmful effect on children with asthma.

The prevalence of asthma remains difficult to determine with precision with no absolute or "gold" standard for diagnosis. A recently developed video questionnaire for epidemiological studies with less reliance on understanding written questions provides another tool for determining prevalence and severity of asthma. This report from the International Study of Asthma and Allergies in Childhood (ISAAC) examines the agreement between the ISAAC video questionnaires on respiratory symptoms and reported asthma. Between December 1993 and April 1995, 4952 children aged 13-14 years in two Canadian communities completed sequentially the ISAAC written and video questionnaires at school. The agreement between responses to the two questionnaires for reported wheeze ever, current wheeze, wheeze on exercise, and nocturnal wheeze (the latter three questions relating to symptoms in the last 12 months), and to any combination of the latter three questions was examined in the full sample and in those reporting diagnosed asthma, using concordance and kappa coefficients as measures of agreement. The prevalences of wheeze ever, current wheeze, wheeze on exercise, and nocturnal wheeze were significantly lower based on responses to the video questionnaire compared with the written questionnaire in both regions in the full sample and in those labeled as having asthma. Although concordance between video and written questionnaires always exceeded 60% and often exceeded 70% for related questions, agreement measured by the kappa statistic for each question was only fair to moderate (kappa = 0.22-0.51). We conclude that the video questionnaire yields lower reported prevalence rates for asthma symptoms, and that there is limited agreement between responses to the two questionnaires that is not explained by issues of language, culture, or literacy., (Copyright 2000 Wiley-Liss, Inc.)

Most wireless phones and their corresponding base stations operate at a very low power output and in the radiofrequency range of 800 to 2000 Megahertz. Current international guidelines protect against thermal biological effects in terms of the local or whole-body specific absorption rate (SAR). Potential non-thermal bio-effects resulting from the use of wireless phones are not established and laboratory (i.e., in vitro, in vivo) studies have shown conflicting results. Epidemiological studies of potential human health effects are few but are expected to emerge in the near future. Challenges to epidemiological research include difficult exposure assessment, selection of appropriate controls, potential confounding bias, and validation of outcome. Scientists, community advocacy groups, and public health professionals must be equipped to critically analyze the emerging evidence within a benefit/risk assessment framework.

Background: Wide variations in the prevalence of asthma, rhinitis and eczema have been reported between regions within Canada and between different countries. The International Study of Asthma and Allergies in Childhood (ISAAC) was developed to provide a standardized tool and methodology to ascertain the prevalence of asthma and allergies in different regions. Comparisons of prevalence rates across geographic regions and at different times may help to identify factors that contribute to the development of these conditions in individuals., Methods: Two Canadian centres, Hamilton and Saskatoon, participated in the ISAAC. A standard questionnaire was distributed through schools and completed by 13- and 14-year-old children and by the parents of 6- and 7-year-old children. Prevalence rates and 95% confidence intervals were calculated for asthma, wheezing, rhinitis and eczema., Results: The overall response rates were 75.1% among the children 6 and 7 years old and 68.6% among those 13 and 14 years old. Among the younger children, the lifetime prevalence of asthma was 17.2% in Hamilton and 11.2% in Saskatoon; the corresponding rates among the older children were 19.2% and 12.2% respectively. The prevalence of wheezing in the 12 months before the survey in the younger group was 20.1% in Hamilton and 14.1% in Saskatoon; in the older group it was 30.6% and 24.0% respectively. The prevalence of rhinitis in the 12 months before the survey was 28.6% in Hamilton and 22.6% in Saskatoon in the younger group and 45.8% and 33.8% respectively in the older group. The prevalence of eczema was slightly higher in Saskatoon in both age groups., Interpretation: High prevalence rates of asthma, rhinitis and eczema exist among school children in Hamilton and Saskatoon, similar to rates in other Western countries. Further studies are required to determine the factors associated with the high rates in the 2 regions and possible reasons for the higher rates in Hamilton.

We describe the hospital utilization of 194 Saskatchewan persons with Fetal Alcohol Syndrome (88% Aboriginal), born between 1973-92. Complete provincial hospitalization data were obtained for 128 patients; partial data for 29 patients. Proportionately more persons missing data were adopted, not living with biological family members or were deceased. The hospital separation rates for the children with FAS, pooled from 1987-91, compared to the 1989-90 Saskatchewan rates were significantly higher (95% level of confidence) for males and females < 1 year, 1-4 years and 5-14 years of age. Relative to Saskatchewan Registered Indians, significantly higher hospitalization rate ratios were observed for males with FAS in all age groups and for females only age 5-14 years. Rate ratios for younger females may not have achieved significance because of missing data. Higher hospitalization rates in children with FAS may not be explained solely by factors associated with ethnicity.

We have found delayed mean bone age in 63 children with fetal alcohol syndrome (FAS). The mean bone age Z-score for boys (n = 31) was -2.12 SDs and for girls (n = 32) was -1.62 SDs. This might suggest that they have potential for catch-up growth. However, experience with children with intrauterine growth retardation suggests that this will not be the case and that FAS children will be of reduced height at maturity. Further support for this assumption was gained from a sample of 26 patients who were followed until at least the age of 14 years for females and 16 years for males. There was no significant change in height Z-scores from early childhood to early adulthood, the mean score being -2.16 SDs and -2.11 SDs at mean ages of 4.83 years and 18.69 years, respectively. On the other hand, there were significant changes in weight and head circumference. The mean weight Z-score changed from -2.10 SDs to -1.14 SDs (p < 0.001). The head circumference mean Z-score in 16 patients was -3.13 SDs at a mean age of 2.79 years and -2.63 SDs at a mean age of 17.37 years (p = 0.013). Short stature can continue to be used as a diagnostic criterion for FAS beyond childhood.

Despite major initiatives in public and professional education about foetal alcohol syndrome (FAS) in Saskatchewan in the last 20 years, its incidence rate has not fallen. The rate was 0.515 per 1,000 live births in 1973-1977 and 0.589 in 1988-1992. Two hundred and seven (207) cases were ascertained, the majority being patients of the Alvin Buckwold Child Development Program in Saskatoon. These individuals were severely handicapped: 72% had at least one malformation, the mean intelligence quotient was 67.8 (range 35-106) and 45.9% had a behaviour problem. Only 25.6% still lived with their biological parents when last seen, and only 27 of 108 cases were in a regular class at school without additional support being necessary. New approaches are needed to reduce the incidence of FAS. Emphasis should be placed on individual case-finding, counselling for high-risk women, and community development programs. We are currently attempting this through a provincial coordinating committee.

Objective: To examine recent trends in the use of inhaled beta 2-adrenergic agonists and inhaled corticosteroids for the treatment of asthma among Saskatchewan residents and to determine whether these trends are in keeping with widely publicized guidelines recommending a reduction in the use of agents to treat symptoms (i.e., inhaled beta 2-adrenergic agonists) and increased use of prophylactic agents (i.e., inhaled corticosteroids)., Design: Descriptive pharmacoepidemiologic study conducted with the use of data from the computerized database of the Saskatchewan Prescription Drug Plan., Setting: Saskatchewan., Patients: Saskatchewan residents 5 to 54 years of age who received one or more outpatient prescriptions for drugs to treat asthma (inhaled drugs, ingested beta 2-adrenergic agonists and ingested methylxanthines) from 1989 to 1993., Outcome Measures: Epidemiologic trends, calculated for each year: number of prescriptions per 1,000 persons; number of patients who received prescriptions for inhaled corticosteroids, inhaled beta 2-adrenergic agonists and any type of drug to treat asthma; mean number of such prescriptions per patient; and weighted mean amount of salbutamol, fenoterol and beclomethasone dispensed per patient., Results: There has been an increase in the proportion of the population receiving prescriptions for drugs to treat asthma. The number of patients receiving these drugs per 1,000 people rose during the study period from 33.38 to 46.59 for any drug to treat asthma, from 24.70 to 33.77 for inhaled beta 2-adrenergic agonists and from 6.1 to 19.9 for inhaled corticosteroids. The mean number of prescriptions per patient decreased steadily for all drugs to treat asthma (from 5.34 in 1989 to 3.88 in 1993), for inhaled beta 2-adrenergic agonists (from 4.35 to 3.09) and for inhaled corticosteroids (from 2.98 to 2.25). The weighted mean amount of inhaled salbutamol dispensed per patient per year decreased by 40%, from 178.08 mg in 1989 to 109.14 mg in 1993. The weighted amount of fenoterol dispensed per patient per year declined even more, by 58%, from 387.91 mg in 1989 to 164.00 mg in 1993. Conversely, the weighted amount of inhaled beclomethasone dispensed per patient per year increased by 35% from 46.95 mg in 1989 to 63.50 mg in 1992, then dropped to 56.17 mg per year in 1993., Conclusion: These data demonstrate a substantial change in Saskatchewan in the prescribing of drugs to treat asthma; they suggest that many physicians responded to current guidelines advocating increased attention to prevention of airway inflammation in the treatment of asthma.

We investigated asthma morbidity in children and adults among Registered Indians in Saskatchewan using hospitalization data for 1970-1989. In Registered Indians, significant increases were observed in the asthma hospitalization rates from 1979 to 1989 in boys and girls under 4 years, boys aged 5-14 years, and female adults aged 15-34 years respectively. In children under 4 years, the asthma hospitalization rates increased from 12.7 per 1000 in 1979 to 21.7 per 1000 in 1989. Asthma hospitalizations were higher among Indian boys than girls in the age group 0-4 years but this was reversed in the age groups 15-34 and 35-64 years. When compared with other Saskatchewan populations, the Indian population in age groups 0-4 and 35-64 years had significantly increased risk for hospitalization for asthma. Even though asthma was reported to be rare among Indians before 1975, we observed increases in asthma morbidity in recent years among Indian children and young adults.

We have previously reported an increasing dose-response relationship between the regular use of beta-agonist inhalers and the risk of asthma death and near death among a cohort of 12,301 subjects who had been dispensed 10 or more prescriptions of asthma drugs from January 1980 to April 1987. That analysis was based solely on information obtained from linkable computerized data bases. Such an association might be explained in part by the tendency of patients with more severe asthma, that is, those at greatest risk for an adverse outcome, to use more beta-agonist medication. To further examine this potential confounding by severity, we gathered clinical information independently from the field on the 129 case patients and their 655 control patients from the matched case-control analysis of 12,301 subjects. In 68% of the control patients with a life-threatening episode and 75% of the matched control subjects, we obtained a valid questionnaire from at least one physician who had seen the patient during the previous 2 yr. Acceptable information on hospitalizations because of asthma was obtained in 87% of those hospitalized. Clinical features associated with an increased risk of fatal and near-fatal asthma were: a history of loss of consciousness or seizures during a previous asthma attack (odds ratio, 10.2; 95% CI, 3.9 to 26.7), a history of attacks of asthma precipitated by eating certain foods (odds ratio, 5.1; 95% CI, 2.4 to 11.1), a clinical score designed to reflect the severity of prior attacks of asthma leading to hospitalization, and prior respiratory acidosis among those in whom a blood gas determination was recorded.(ABSTRACT TRUNCATED AT 250 WORDS)

Oral colonization by Pseudomonas aeruginosa possibly precedes the pulmonary infection process in cystic fibrosis (CF) patients. As bacterial aggregates may play a role in establishment of pulmonary infections, involvement of IgA and cations in CF patient saliva-mediated aggregation of P. aeruginosa was investigated. For colonized patients, P. aeruginosa aggregation correlated with bacterial-specific and total salivary IgA. Cation or IgA depletion reduced P. aeruginosa aggregation by saliva from all patients. However, if cations were removed before IgA, and saliva was then reconstituted with calcium, only colonized patient saliva showed reduced aggregation. Aggregation by IgA-depleted saliva was augmented by reconstituting with original IgA. CF patient saliva-mediated aggregation of P. aeruginosa thus is cation-dependent and enhanced by bacterial-specific IgA. Characterizing the interactions among bacterial aggregating factor(s), cations, and antibodies in CF saliva will help clarify the link between P. aeruginosa oral colonization and pulmonary infections in CF patients.

The hospitalization rates for gastrointestinal and respiratory illnesses in children under five years of age were examined on two Indian reserves in Northern Saskatchewan. The gastrointestinal illness rate was used as an index of waterborne disease, and the respiratory rate as an index of general health and of local customs affecting hospitalizations. The reserve rates were compared with those for other Saskatchewan status Indians and for other Saskatchewan residents. The risk ratios between the reserves and other Indians, and between the reserves and other Saskatchewan residents, were increased for both gastrointestinal and respiratory illnesses. The risk ratio of gastrointestinal rate divided by respiratory rate was greater for either reserve than for other Indians or other Saskatchewan residents. Waterborne illnesses were an even greater problem on the two study reserves than on other reserves. Comparing hospitalization rates for different illness groups is a useful method to compare the effect of different social factors.

Objective: To examine the relationship between patterns of use of inhaled beclomethasone dipropionate and the risk of fatal and near-fatal asthma., Design: Nested case-control analysis of a historical cohort; a further analysis., Setting: The 12,301 residents of Saskatchewan aged 5 to 54 years who were dispensed 10 or more asthma drugs from 1978 to 1987., Patients: The 129 persons who experienced asthma death (n = 44) and near-death (n = 85) and their 655 controls matched as to age and date of entry into the cohort, with the additional matching criteria of at least one hospitalization for asthma in the prior 2 years, region of residence, and having received social assistance., Main Outcome: Life-threatening attacks of asthma defined as death due to asthma or the occurrence of hypercarbia, intubation, and mechanical ventilation during an acute attack of asthma., Results: After accounting for the risk associated with use of other medications and adjustment for markers of risk of adverse events related to asthma, subjects who had been dispensed, on average, one or more metered-dose inhalers of beclomethasone per month over a 1-year period had a significantly lower risk of fatal and near-fatal asthma (odds ratio, 0.1; 95% confidence interval, 0.02 to 0.6)., Conclusion: These data support recent guidelines from several countries that recommend the use of inhaled corticosteroids in moderate and severe asthma.

The aggregation and adherence activity of P. aeruginosa, mediated by whole saliva from cystic fibrosis (CF) patients and non-CF subjects, was investigated. CF saliva-mediated aggregation of P. aeruginosa was stronger than the activity of non-CF saliva. Likewise, P. aeruginosa adherence to buccal epithelial cells (BEC) of CF patients was stronger than to BEC of non-CF subjects. Adherence of non-mucoid P. aeruginosa to BEC of CF patients was increased by saliva, whereas the mucoid variant was not. CF patients colonized with P. aeruginosa showed higher adherence of the non-mucoid variant than non-colonized CF patients. CF patients with high saliva-mediated adherence of non-mucoid P. aeruginosa also had high salivary aggregation activity. Increased CF saliva-mediated aggregation activity may be linked to the increased non-mucoid P. aeruginosa adherence to BEC of CF patients.

Parents, community health nurses (CHNs) and physicians in Saskatoon were surveyed to determine if specific components of well-baby services provided by CHNs and physicians were duplicated. A response was obtained from 348 (81%) of the parents, 34 (89%) of the CHNs and 129 (87%) of the physicians. Results of the study indicate that there is extensive duplication of measurements taken by CHNs and physicians at the two, four, six, and twelve-month well-baby visits, especially that of height and weight. Content of well-baby care was also examined. The percentage of both physicians and CHNs who "usually or always" perform specific tasks at each well-baby visit was very high, particularly screening tests and inquiries about nutrition. Assessments and inquiries regarding development were performed less frequently, as were inquiries about safety issues.

Background: Morbidity and mortality from asthma appear to be increasing, and it has been suggested that medications used to treat asthma are contributing to this trend. We investigated a possible association between death or near death from asthma and the regular use of beta 2-agonist bronchodilators., Methods: Using linked health insurance data bases from Saskatchewan, Canada, we conducted a matched case-control study of subjects drawn from a cohort of 12,301 patients for whom asthma medications had been prescribed between 1978 and 1987. We matched 129 case patients who had fatal or near-fatal asthma with 655 controls (who had received medications for asthma but had not had fatal or near-fatal events) with respect to region of residence, age, receipt of social assistance, and previous hospitalization for asthma., Results: The use of beta-agonists administered by a metered-dose inhaler was associated with an increased risk of death from asthma (odds ratio, 2.6 per canister per month; 95 percent confidence interval, 1.7 to 3.9) and of death or near death from asthma, considered together (odds ratio, 1.9; 95 percent confidence interval, 1.6 to 2.4). For death from asthma, use of the beta-agonist fenoterol was associated with an odds ratio of 5.4 per canister, as compared with 2.4 for the beta-agonist albuterol. On a microgram-equivalent basis, the odds ratio for this outcome with fenoterol was 2.3, as compared with 2.4 with albuterol., Conclusions: An increased risk of death or near death from asthma was associated with the regular use of inhaled beta 2-agonist bronchodilators, especially fenoterol. Regardless of whether beta-agonists are directly responsible for these adverse effects or are simply a marker for more severe asthma, heavy use of these agents should alert clinicians that it is necessary to reevaluate the patient's condition.

Two recent epidemiologic case-control studies suggested that fenoterol, a selective beta-adrenergic agonist, was associated with an increase in the risk of asthma death. The results of these studies were criticized because of methodologic problems in the choice and selection of control subjects; the different methods used to gather exposure data in cases and control subjects; and because of inadequate classification and adjustment for asthma severity. In response to this controversy, a new study is underway, the Saskatchewan Asthma Epidemiology Project. The SAEP includes two complementary studies, an historic cohort and a case-control analysis, that employ the computerized databases of the Saskatchewan Health Department. A unique aspect of the SAEP is the attempt to incorporate knowledge of asthma physiology and management into the design of the studies. Specifically, the study design recognized the role of antiinflammatory drugs in asthma treatment; the distinction between asthma death and near-fatal asthma; the severity of asthma; patterns of drug use; and the distinction between inadequate clinical care and disease severity. The strategies we employed in the SAEP may prove helpful to investigators whenever clinical and biologic processes create sources of potential bias requiring special procedures for the design and analysis of epidemiologic studies.

Objective: To determine the difference in pregnancy outcome between native Indians and the provincial population in Saskatchewan., Design: Retrospective analysis of data collected from all birth and death registration forms., Setting: Saskatchewan., Main Outcome Measures: Incidence of low birth weight and rates of stillbirth and of neonatal and infant death., Results: The neonatal death rate was higher in the Indian population than in the provincial population during the study period; the difference between the two groups in the rate decreased markedly after 1982. The rates of stillbirth and infant death were also higher among the Indians, and the difference persisted during the study period. The incidence of low birth weight and the rate of stillbirth were highest in the youngest and oldest maternal groups in the provincial population; however, the pattern was markedly different among the Indians, teenaged mothers having the best outcomes., Conclusion: Further studies are needed to determine the relation between maternal age and fetal outcome among native Indians.

A female infant developed apneic spells due to hypoglycemia at 73 hours of life. It was impossible to maintain the blood glucose level despite continuous intravenously given dextrose, cortisone, diazoxide, and a low-leucine diet. A subtotal pancreatectomy was performed but there was no evidence of islet cell adenoma. On second laparotomy, the head of the pancreas was removed, and on microscopic examination, islet cell adenomatosis was found. A good clinical recovery followed. Follow-up at age 3 years and 4 months shows apparently normal mental and physical development.

Patients with cystic fibrosis (CF) are often hosts to colonies of both mucoid and nonmucoid strains of Pseudomonas aeruginosa. The major pathogens for chronic and recurrent pulmonary infection in these patients are the mucoid variants of P. aeruginosa. Of the 31 CF patients studied, 14 patients yielded both mucoid and nonmucoid strains of P. aeruginosa from the various oral ecologic sites and saliva. Of the sites tested, the dorsum of the tongue gave the highest yield of P. aeruginosa (27 strains), followed by the buccal mucosa (17 strains), saliva (15 strains), and dental plaques (6 strains). Eleven patients had P. aeruginosa in the oral cavity and sputum simultaneously. Antibiotic susceptibility tests on these multiple isolates suggest that CF patients may be cocolonized or coinfected by two or more strains of P. aeruginosa. Therefore, it may be important to identify multiple isolates of P. aeruginosa, not only from sputum cultures but also from oral cultures, for antibiotic-susceptibility testing. Oral colonization by the mucoid variants of P. aeruginosa may lead to further colonization in the lower respiratory tract and subsequent pulmonary infection in CF patients.

Interbacterial adhesion between strains of Pseudomonas aeruginosa and strains of indigenous oral bacteria, both of which were isolated from the oral cavity of cystic fibrosis patients, was investigated by the phenomenon of the coaggregation reaction. A total of 22 strains of P. aeruginosa were isolated from the oral cavity of 17 patients and examined for their abilities to coaggregate with 5 strains each of Streptococcus sanguis, Streptococcus mitis, Actinomyces viscosus, and Actinomyces naeslundii. Coaggregation reactions were common between these oral bacteria and both the mucoid and nonmucoid variants of P. aeruginosa. All strains of P. aeruginosa were also able to agglutinate neuraminidase-treated or untreated human erythrocytes of blood types A, B, and O. Positive coaggregation reactions were further characterized by determining the effects of several sugars, and of heat and protease treatments of the bacteria. None of the coaggregtion reactions were inhibited by 0.05 M lactose, galactose, glucose, fucose, or mannose. All coaggregation reactions were dependent upon heat- and protease-sensitive components of the Pseudomonas. Thus, the interbacterial adhesions between P. aeruginosa and the oral bacteria studied appears to involve adhesins on the Pseudomonas cell, which bind to complementary receptors, on the cell surfaces of oral bacteria. The apparent prevalence and diversity of interbacterial adhesions between P. aeruginosa strains originating from the oral cavity of cystic fibrosis patients and strains of the indigenous oral bacteria suggest that some of these reactions may affect the extent to which P. aeruginosa colonizes in the oral cavity of cystic fibrosis patients, and thereby, influence susceptibility of the host to infection.

Fever, which is the regulation of body temperature at an elevated level, must be differentiated from hyperthermia. The pathogenesis of fever involves exogenous pyrogens acting on macrophages/monocytes to produce the endogenous pyrogen, interleukin-1, which acts on the thermoregulatory centre and also has important effects on the body's immune responses to infection. Fever by itself is rarely harmful, and there is no evidence that febrile seizures produce long-term sequelae. On the other hand, fever may be part of the body's innate protection against infection. The main reason for treating a fever in a child is to relieve discomfort. Acetaminophen should be the drug of first choice in treatment, and sponging, if used at all, should be employed only after acetaminophen has been given first. Education of parents about fever management can be helpful.

In order to manage diabetes mellitus in children, the physician must understand the principles of insulin action and dosage adjustment, meal planning, growth assessment, and the effects of exercise. The objectives of office supervision include ongoing education of the patient and family, excellent control of the diabetes, and the maintenance of normal growth and development, emotionally as well as physically.

We carried out a case-control study of the hospital charts of 91 infants with infantile hypertrophic pyloric stenosis (IHPS) to determine the feeding practices at the time of discharge from the neonatal nursery. We excluded infants whose feeding might have been influenced by confounding factors. The infants were matched with controls for gestational age. The mean birth weight of the IHPS group was 3501 g and of the control group 3543 g. The male:female ratio for the IHPS group was 5.5. The odds ratio of male predominance was 4. We found that bottle-feeding was 2.9 times more prevalent among the infants with IHPS than among the control subjects. We speculate that the recently observed decrease in the incidence of IHPS is due to the decline in bottle-feeding.

This paper describes nine babies who appeared contented yet failed to thrive while being exclusively breast-fed. In each case the mother felt that her child was satisfied with the feedings. Following appropriate management all the infants were above the 80th percentile for both weight and weight for length. Five infants had achieved 110% to 120% and three more than 120% of the expected weight for length. This tendency to become overweight might be explained by inactivity or a defect in appetite control.

Oral and sputum isolates of Pseudomonas aeruginosa in patients with cystic fibrosis were investigated. Of the 17 patients studied, 12 patients (71%) yielded both mucoid and nonmucoid variants of Pseudomonas aeruginosa from sputum and (or) various oral ecological sites, such as buccal mucosa, tongue dorsum, dental plaques, and saliva. A total of 51 strains of mucoid and nonmucoid Pseudomonas aeruginosa were isolated from these patients and were phenotypically characterized by both pyocine typing and serotyping. Five patients (42%) were colonized or infected by a single strain of Pseudomonas aeruginosa, whereas 7 patients (58%) were cocolonized or coinfected by two or more phenotypically different strains of Pseudomonas aeruginosa. To understand the mechanisms involved in Pseudomonas aeruginosa colonization, it may be necessary to identify multiple isolates of Pseudomonas aeruginosa not only from the sputum but also from the various oral ecological sites and to further explore the role of the oral cavity in this colonization.

The mechanism of saliva-mediated aggregation of Pseudomonas aeruginosa in subjects with and without cystic fibrosis (CF) was investigated. Virtually all saliva from CF patients that we tested strongly agglutinated the Pseudomonas cells and was heat stable to 56 degrees C, whereas saliva from subjects without CF had a decreased aggregating ability and was heat sensitive. When saliva was treated with neuraminidase and proteases, and also when P. aeruginosa cells were treated with mixed gangliosides, there was a decrease in aggregating activities. However, neither the addition of the acid-hydrolyzed ganglioside nor the treatment of the P. aeruginosa cells by sugars had any effect on subsequent aggregating activities. Therefore, the release of sialic acid by enzymatic treatments of saliva, as well as the blockage of the sialic acid-binding sites on the cell wall by mixed gangliosides, resulted in the parallel loss of saliva-mediated aggregating activity of P. aeruginosa. The level of free sialic acid released by endogenous neuraminidase was higher in the saliva from CF patients than in that from the non-CF subjects examined. The increased aggregation of P. aeruginosa mediated by saliva from patients with CF seems to be directly related to the sialic acid content present, suggesting that this acid molecule acts as the salivary receptor for P. aeruginosa.

It is widely believed by both physicians and microbiologists that bacteremia is a rare event in shigellosis. We report two cases of shigellosis with positive blood cultures and review 68 cases reported in the literature between 1963 and 1981. We suggest that detection of bacteremia in shigellosis may be facilitated by a greater awareness of the following findings. 1. Eighty-seven percent of all cases of shigellosis with bacteremia reported in the literature during the 18-year period reviewed occurred in pediatric patients under 16 years of age. The majority of detected shigellemia cases were in children under 5 years of age. 2. Bacteremia is frequently intermittent and its detection is aided by collection of serial blood cultures with an adequate volume of blood. 3. Positive blood cultures were obtained most frequently on Days 1 to 2 and on Days 5 to 7 following onset of symptoms. 4. The case fatality rate of reported shigellemia cases was 46%. Although some of these findings may reflect a patient selection bias of cases reported in the literature, we believe that a greater awareness among clinicians and microbiologists of the potential value of blood cultures in the diagnosis and management of shigellosis will eventually lead to a better understanding of the pathogenesis of this infectious disease.

In patients with cystic fibrosis, plain chest radiographs may suggest the presence of bronchiectasis, bronchoceles, hilar adenopathy, or pulmonary arterial hypertension. We compared computed tomography (CT) with conventional chest radiography in 12 patients. CT clearly reveals the cause of increased linear markings, nodular lesions, and enlarged hila as seen on plain chest radiographs. It showed that nine patients had hilar adenopathy, five had enlarged pulmonary arteries, and 11 had bronchiectasis. Bronchoceles, a finding that may influence therapy, were seen on seven CT scans but on only four of the plain films.

Liver abnormalities were found in three patients with fetal alcohol syndrome. The histological appearance was different in each case. Thick, sclerotic central veins were seen in two of the three cases. One patient had features typical of congenital hepatic fibrosis and cystic disease of the kidneys. Findings in these patients indicate that some cases of congenital hepatic fibrosis might be caused by high maternal alcohol ingestion in pregnancy.

We reviewed the incidence rates of infantile hypertrophic pyloric stenosis (IHPS) and pylorospasm in Saskatchewan from 1970 to 1985 and found a marked decrease in the rates after 1976. As expected, there was a preponderance of males among those with IHPS and among those with pylorospasm discharged from hospital between 1 and 3 months of age. No seasonal pattern was observed. We believe that the decrease in incidence rates was related to environmental influences, such as changes in the methods of feeding observed since 1977.

The single breath diffusing capacity of the lung for carbon monoxide (Dsb) was measured using three equations to describe CO uptake separately during inhalation, breath holding, and exhalation in 24 patients with cystic fibrosis and 30 control subjects with similar age and height distributions. Using the control group, we developed two prediction equations for Dsb: one based on height, age, and sex; and another based on alveolar lung volume (VA) to the 2/3 power. We also developed a prediction for Dsb/VA (Kco) based on height. The Dsb as percent predicted (% pred) using either prediction equation decreased with increasing age and height as well as with decreasing % pred maximal midexpiratory flow rate (FEF25-75) in cystic fibrosis patients but not in controls. The Kco (% pred) also decreased in cystic fibrosis with increasing age and decreasing percent pred FEF25-75. We conclude that in patients with cystic fibrosis, Dsb decreases with variables that relate to increasing disease severity (age, height, and increasing airflow obstruction).

A problem-solving approach is used to illustrate principles of managing diabetes mellitus in children. Situations discussed include adjustments for hypo- and hyperglycemia and vigorous activity, and care of the diabetic child who has another illness. The usefulness of referral to a diabetes education centre is emphasized.

The aggregation of mucoid and nonmucoid Pseudomonas aeruginosa by submandibular, parotid, and whole saliva from patients with cystic fibrosis (CF) and non-CF subjects was investigated. There were significant differences (P less than 0.01) in aggregation of mucoid and nonmucoid variants of P. aeruginosa by submandibular and whole saliva from CF patients and non-CF subjects. However, the differences in the parotid secretion were not as pronounced. Patients with CF who were colonized with P. aeruginosa demonstrated a significantly higher (P less than 0.05) percent aggregation of the mucoid variants by the submandibular secretion and of both mucoid and nonmucoid variants by whole saliva, compared with corresponding secretions from patients with CF not colonized with this pathogen. The parotid saliva aggregation activity was not markedly different for the two groups with CF. From patients with CF, whole saliva demonstrated a higher percent P. aeruginosa aggregation than did the submandibular saliva. In non-CF subjects, however, the percent aggregation of P. aeruginosa by submandibular saliva was higher than that by whole saliva. Our results indicate that the sero-mucous products of the submandibular gland have a more significant role in P. aeruginosa aggregation than the serous secreting parotid cells and that the submandibular secretion is possibly responsible for the differences in oral colonization by this pathogen in subjects with and without CF.