Frequency of isolated cutaneous involvement in adult mastocytosis: a cohort study.

BACKGROUND: Mastocytosis is characterized by the accumulation/proliferation of abnormal mast cells. The frequency of isolated cutaneous involvement in adults with mastocytosis has not been fully determined. The main objective of our study was to assess the frequency of isolated cutaneous mastocytosis (CM) in adults with mastocytosis skin lesions. The second objective was to compare the clinical, histological, biological and imaging features in patients with isolated CM and patients with systemic mastocytosis (SM). METHODS: We included all patients with histology-proven mastocytosis skin lesions between January 2009 and December 2017. The mastocytosis diagnosis was made according to the international diagnostic criteria. All data were collected from a dedicated specific case report. RESULTS: Among 160 patients with mastocytosis skin lesions, 25 patients had isolated CM (15.6%), 105 had SM and 30 (18.7%) patients had undetermined mastocytosis. Skin KIT mutation (OR: 51.9, 95% CI: 3.9-678, P = 0.001) and high bone marrow tryptase (OR: 97.4, 95% CI: 10.3-915, P = 0.001) were strong predictors of SM. The prevalence of osteoporosis was higher in the SM population than in the isolated CM population. Moreover, a decrease in bone mineral density over a short period of follow-up (1-2 years) was associated with SM. There were no differences between the two groups regarding the frequency of mast cell activation symptoms, the presentation of skin lesions, the number of mast cells in the dermis and the level of serum tryptase. We propose considering the KIT mutation status and bone marrow tryptase levels to aid the diagnosis of isolated CM in adult mastocytosis patients. CONCLUSION: Only a small minority of adults with mastocytosis skin lesions has isolated cutaneous involvement. In 18.7% of mastocytosis cases, even complete workup does not allow for a precise classification of patients.

Evaluation of the New World Health Organization Case Definition of Severe Acute Respiratory Infection for Influenza Surveillance During the Peak Weeks of Two Influenza Seasons in Quebec, Canada.

During the peak of the 2012-2013 and 2014-2015 influenza seasons in Quebec, Canada, the sensitivity of the new World Health Organization (WHO) case definition of severe acute respiratory infection (SARI) in <5-year-old children was 65% for polymerase chain reaction-confirmed influenza and 79% for other respiratory viruses (ORVs), whereas its specificity and positive predictive value were approximately 2- and 4-fold lower for influenza than ORVs (25% vs 40% and 18% vs 76%, respectively). The use of the WHO SARI definition for influenza surveillance in children should be interpreted with caution according to the specific surveillance goals.

[Increase of Hantavirus infections in France, 2003]. / Recrudescence des infections à Hantavirus, France 2003.

BACKGROUND: Hantaviral infections causing hemorrhagic fever with renal syndrome are endemic in North Eastern France. Humans are contaminated by the inhalation of aerosols contaminated by rodent faeces. In February 2003, the National reference centre (NRC) for hemorrhagic fevers detected an increased number of cases. An investigation was carried out to confirm the outbreak and take appropriate control measures. METHODS: Cases were collected by the NRC. A case was defined as a person living in France with symptoms compatible with hantaviral infection and a positive blood test both for specific Puumala IgM, and IgG. Clinical information and at-risk exposures during the 2 weeks before onset were recorded. RESULTS: In 2003, 128 cases were diagnosed (61 in 2002). The median age of patients was 38, 77% were men and 82% were hospitalized. Patients were living in North-Eastern France. Clusters were detected in the Ardennes and Oise districts. Occupation (35%) (in agriculture, forestry, and construction work), manipulation of firewood (35%), gardening (29%), and outdoors leisure (14%) were identified as at-risk exposures in these cases. CONCLUSIONS: An increased number of positive diagnoses of hantaviral infections was confirmed. The location and at-risk exposures of the cases were identical in previous investigations. Exclusion and prevention of rodents' access to houses and avoiding the inhalation of contaminated dust are the only possible prevention measures of hantaviral infections. Information about the disease and its prevention needs to be made widely available to both healthcare professionals and the general population living in endemic areas.

Effectiveness of a single dose of acellular pertussis vaccine to prevent pertussis in children primed with pertussis whole cell vaccine.

We estimated the protection given by one booster dose of acellular pertussis vaccine (aP) given at 18 months or before school entry to children already primed with whole cell vaccine (wP). Case-control studies were conducted in these two age groups. In children who received or were eligible to receive their 18 months booster, the risk of pertussis was 1.4 and 3.6 times higher for those with 4 and 3 wP, respectively, compared to those with 3 wP + 1 aP. In 5 and 6 yr old children, the risk of pertussis among the subjects with 5 and 4 wP, was 1.4 and 2.1 times higher respectively than in those who received 4 wP + 1 aP. A single dose of aP increased the protection against pertussis and this protection was greater than that obtained with a wP booster.

Importance of attributable risk in monitoring adverse events after immunization: hepatitis B vaccination in children.

OBJECTIVES: Most vaccine safety data present only the postvaccination incidence of all adverse events rather than an estimate of attributable risk. This study sought to illustrate the difference between the 2 estimates with data from a hepatitis B immunization program. METHODS: The incidence of health problems occurring before and after each dose of hepatitis B vaccine in a cohort of 1130 children were compared. RESULTS: Although 47.5% of all children reported an adverse event during the 4 weeks following each of the 3 doses, adverse events attributable to immunization occurred in only 10.6% of children. CONCLUSIONS: Postimmunization incidence systematically overestimates the risk of adverse events. Estimating actual attributable risk is necessary to avoid false beliefs regarding immunization.

Burden of chickenpox on families: A study in Quebec.

OBJECTIVE: To estimate the nonhospital costs of treating chickenpox and to ascertain the opinion of parents regarding the usefulness of vaccination. DESIGN: Retrospective postal survey. SETTING: Province of Quebec. PARTICIPANTS: Random sample of 3333 families with children aged six months to 12 years. OUTCOME MEASURES: For cases of chickenpox that occurred between September 1, 1997 and August 31, 1998, the use of health services, time away from school or work, patient care required, direct and indirect costs for the families and the health care system, and the opinion of parents regarding chickenpox and the vaccine were evaluated. RESULTS: The response rate was 64.7%, and 18.8% of households reported a history of chickenpox, a total of 693 cases. A physician was consulted in 45.8% of these cases, and medication was used in 91.7%. The frequency of hospitalizations was 0.6%. Time away from work or school caused by the disease was 4.1 days on average, with 46.5% of absences being attributed to the risk of contagion. The total average cost of a case of chickenpox was $225. Direct expenses for households accounted for 11% of the total cost, public sector direct costs 7%, indirect costs related to absence from work 38% and caregiving time 45%. A majority of parents (70%) were in favour of a systematic childhood immunization program. CONCLUSIONS: Chickenpox without complications is disruptive for families, but the direct costs for families and the public sector are relatively small.

Morbidity of pertussis in adolescents and adults.

The effect of age on the clinical presentation of pertussis was assessed in 664 adolescent and adult cases. Complications were more frequent in adults than in adolescents (28% vs. 16%). Pneumonia occurred in 2% of patients <30 years old but in 5%-9% of older patients. Urinary incontinence occurred in 34% of women >/=50 years old. Duration of cough, risk of sinusitis, and number of nights with disturbed sleep increased with smoking and asthma. The secondary attack rate in other household members >/=12 years was 11%. Pertussis in secondary case patients was less severe than in index case patients but presented with classic symptoms. The main source of infection in adolescents was schoolmates or friends; in adults it was workplace or their children. Teachers and health care workers had a greater risk of pertussis than did the general population. The burden of disease appears to increase with age, with smoking, and with asthma.

[Vaccination against influenza in elderly persons: some current presumptions]. / Vaccination contre la grippe des personnes âgées: quelques préjugés courants.

A telephone survey in March 1994 revealed that only 70% of 185 persons surveyed aged 65 and over were offered influenza vaccine during the last flu shot campaign; the sample was taken among non-institution residents of the Quebec City area who were likely to have regular health professional contact. Misinformation concerning influenza infection and vaccine remains widespread: 30% of the people surveyed still believe that the vaccine can transmit the virus and 21% consider the vaccine ineffective. Incorrect beliefs are significantly more prevalent among the unvaccinated population: 12% stated that they were allergic to the vaccine; in fact, true allergies are rare. Health professionals should recognize that elderly people, though in regular contact with the health care system, may not have been offered the influenza vaccine and may have inadequate information or incorrect beliefs regarding influenza and its preventability.

Impact of a mass immunization campaign against serogroup C meningococcus in the Province of Quebec, Canada.

A mass immunization campaign was conducted in the Province of Quebec, Canada, during the winter of 1993, following an increase in the incidence of meningococcal disease, which was mainly caused by a virulent clone of Neisseria meningitidis, serogroup C, serotype 2a. About 1.6 million doses of the polysaccharide vaccine were administered, covering 84% of the target population aged between 6 months and 20 years; the overall cost was about 25.5 million Canadian dollars. Cases notified to the regional health authorities by clinicians, hospital laboratories, and the provincial reference laboratory from January 1990 up to March 1994 have been included in the analysis. In the first year following the campaign, the incidence of the disease dropped markedly among vaccinees as well as the unvaccinated fraction of the target population, while it remained unchanged among persons aged more than 20 years. This suggests the existence of herd immunity. The overall field efficacy of the vaccine was 79%, more in teenagers and less in under-5-year-olds. A minimum of 37 cases were prevented during the first year.