Post-tussive Vomiting Research Articles

Concentrations of Immunoglobulin G Antibodies Against Pertussis Toxin Does Not Decrease Over a Long Period of Time in Japan.

Objective Adult patients with pertussis rarely show typical symptoms, such as paroxysmal coughing, inspiratory "whoop", or post-tussive vomiting. While a culture is regarded as the gold standard for diagnosis, the sensitivity is very low. Therefore, the diagnosis of pertussis in adults in clinical practice is mostly based on single-sample serology using an enzyme-linked immunosorbent assay (ELISA) with the pertussis toxin antigen. Various cut-off values for the anti-pertussis toxin IgG (PT-IgG) have been proposed. It has been reported that concentrations of PT-IgG fall below the defined cut-off about 4.5 months after infection on average, and within 1 year in most patients. We investigated the distribution and time course of the PT-IgG levels. Methods The data were collected from the medical records. Patients The study retrospectively identified subjects who had visited Ikebukuro Otani Clinic, which is a specialized clinic for patients with cough. We retrospectively reviewed 406 patients with PT-IgG measurements to investigate the age distribution of PT-IgG levels. The changes in PT-IgG levels over time were assessed in the 205 patients who had more than one PT-IgG measurement. Results PT-IgG levels were ≥100 EU/mL in more than 15% of subjects. The PT-IgG levels of a few subjects had diminished over a long period of time. Conclusion A PT-IgG level greater than the defined cut-off value simply indicates past infection or immunization in most subjects. As such, a single measurement of PT-IgG using the cut-off values might lead to overdiagnosis of pertussis. Further data collection and analysis are required.

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Importance of Enhanced Surveillance for Prevention of Pertussis in Children.

Bordetella pertussis infection causes considerable morbidity, even in countries with high vaccination coverage. Surveillance of pertussis is usually passive and based on mandatory reporting. We assessed the epidemiologic and clinical characteristics of pertussis cases detected by passive or enhanced surveillance. A prospective population-based study was carried out from January 2012 to December 2013 in Catalonia and Navarre, 2 Spanish regions with a total population of 8.2 million. For each confirmed case, variables of age, sex, clinical symptoms, laboratory results and vaccination status were investigated. Associations between the variables studied and the type of surveillance were assessed by odds ratio (OR) and its 95% confidence interval (CI). Logistic regression was used to estimate adjusted OR (aOR). In children <18 years of age, passive surveillance was the most important source of detection (95.7% in <1 year). In children 5-10 years of age, passive surveillance detected 67.5% of cases. In those ≥18 years, enhanced surveillance was the most frequent source of case detection (82.5%). Inspiratory whoop (aOR: 1.94; 95% CI: 1.40-2.70), apnea (aOR: 1.92; 95% CI: 1.28-2.87) and posttussive vomiting (aOR: 1.43; 95% CI: 1.04-1.96) were symptoms included in the clinical case definition that were associated with passive surveillance. Underreporting of symptomatic cases is important not only in adults, but also in children >1 year of age and suggests that providing clinics with free, fast laboratory diagnostic tests, together with enhanced surveillance of family contacts of any age is necessary to better determine existing cases. Enhanced surveillance may be helpful to better understand transmission patterns in the family and in the community.

A retrospective study of acute pertussis in Hasan Sadikin Hospital–Indonesia

ObjectiveTo describe the representation of pertussis diagnosis in children. MethodsA retrospective observational study was performed on pediatric pertussis and pertussis-like syndrome registry for children <14 years of age documented from October 2008 to December 2014 in Hasan Sadikin Hospital, Indonesia. Demographic data, signs and symptoms at presentation, case definition (probable, confirmed), possible pertussis contact, pertussis vaccination status, results of Bordetella pertussis (B. pertussis) culture, complications, and outcome were recorded. ResultsSixty-one probable and two confirmed pertussis were documented. Male and female ratio was 1:1, mostly presented with shortness of breath, 24 (38%) subjects had posttussive vomiting, 10 (16%) had whooping-cough. Ten patients (16%) were reported to have adult possible pertussis contact. Only 2 infants had previous pertussis vaccination. All subjects presented in the second week of illness were all diagnosed as bronchopneumonia but two. The mean age was 6 months, ranging from 0–50 months. One subject required mechanical ventilation. B. pertussis culture was performed only in 35 (56%) subjects but positive only in two. There were no fatal cases, 55 (87%) including the subject who need mechanical ventilation had good outcome. ConclusionsMostly patients were admitted on paroxysmal phase when no more active B. pertussis could be found from nasopharyngeal secret. A rigorous history taking particularly excessive cough, posttussive vomitting, and pertussis vaccination status need to be taken into account.

Case 6-2015

Presentation of Case Dr. Mark A. Goldstein (Pediatrics): A 16-year-old boy was seen in the adolescent medicine outpatient clinic of this hospital in late spring because of coughing spells. The patient had been well until approximately 3 weeks before the current presentation, when cough and nasal congestion developed and persisted, without fever or chills. He took fexofenadine hydrochloride, without improvement. Three days before the current presentation, he awoke at night with a severe coughing spell, with associated post-tussive emesis and trouble breathing. His parents took him to the emergency department of another hospital. On examination, he appeared to be in . . .

Pertussis Accompanying Recent Mycoplasma Infection in a 10-Year-Old Girl.

Recently, the incidence of pertussis has been increasing; however, reports on mixed infection of pertussis with other respiratory pathogens are rare in highly immunized populations. We report the case of a 10-year-old girl who presented with cough, post-tussive emesis, and fever. She was subsequently diagnosed with bronchopneumonia. Although she had received five doses of diphtheria-tetanus-acellular pertussis vaccine, polymerase chain reaction of her nasopharyngeal aspirate confirmed Bordetella pertussis infection. In addition, serologic testing for Mycoplasma pneumoniae was also positive. The patient was treated with roxithromycin without any complications. This is the first report of mixed B. pertussis and M. pneumoniae infection in Korea. To avoid under-diagnosis, pertussis should be considered in patients with chronic cough even when other respiratory pathogens have been documented.

Role of Atypical Pathogens and the Antibiotic Prescription Pattern in Acute Bronchitis: A Multicenter Study in Korea.

The role of atypical bacteria and the effect of antibiotic treatments in acute bronchitis are still not clear. This study was conducted at 22 hospitals (17 primary care clinics and 5 university hospitals) in Korea. Outpatients (aged ≥ 18 yr) who had an acute illness with a new cough and sputum (≤ 30 days) were enrolled in 2013. Multiplex real-time polymerase chain reaction (RT-PCR) was used to detect five atypical bacteria. A total of 435 patients were diagnosed as having acute bronchitis (vs. probable pneumonia, n = 75), and 1.8% (n = 8) were positive for atypical pathogens (Bordetella pertussis, n = 3; B. parapertussis, n = 0; Mycoplasma pneumoniae, n = 1; Chlamydophila pneumoniae, n = 3; Legionella pneumophila, n = 1). Among clinical symptoms and signs, only post-tussive vomiting was more frequent in patients with atypical pathogens than those without (P = 0.024). In all, 72.2% of the enrolled patients received antibiotic treatment at their first visits, and β-lactams (29.4%) and quinolones (20.5%) were the most commonly prescribed agents. In conclusion, our study demonstrates that the incidence of atypical pathogens is low in patients with acute bronchitis, and the rate of antibiotic prescriptions is high.

Occurrence of 3 Bordetella Species During an Outbreak of Cough Illness in Ohio

An increase in laboratory diagnosis of pertussis was noted in central Ohio during 2010. Diagnosis was made using a polymerase chain reaction assay targeting the multicopy insertion sequence IS481, which is found in both Bordetella pertussis (Bp) and Bordetella holmesii (Bh). An increase in specimens testing positive for Bordetella parapertussis (Bpp) using insertion sequence IS1001 was also noted. Nasopharyngeal swab specimens submitted April 1, 2010, to March 31, 2011, were tested using a multiplex polymerase chain reaction assay for Bp/Bh (IS481) and Bpp followed by singleplex assays for Bp and Bh. A subgroup of specimens was also cultured for Bordetella species, and antimicrobial susceptibility testing was performed on recovered organisms. Demographic and clinical features were compared for patients with Bp, Bh and Bpp. Of 520 IS481-positive specimens, 214 (41.1%) were positive for Bp, 79 (15.2%) were positive for Bh and 5 (1.0%) were positive for both Bp and Bh; 222 (42.7%) were negative for both targets. An additional 220 specimens were positive for Bpp. Among a sample of 155 IS481-positive specimens, 40, 15 and 0 were culture positive for Bp, Bh and Bpp, respectively. Among a sample of 55 BparaIS1001-positive (Bpp) specimens, 22, 0 and 0 were culture positive for Bpp, Bp and Bh, respectively. All Bordetella species were susceptible to macrolide antibiotics. Patients with Bh were older than patients with Bp, who were older than those positive for Bpp (mean ages: 12.0, 8.0 and 4.2 years, respectively; P < 0.001). One or more classic signs of pertussis (ie, paroxysmal cough, whoop, post-tussive emesis) were seen in 55.9% of 263 patients (59 Bp, 24 Bh, 80 Bpp and 100 negative for Bordetella species), but did not differ statistically among the groups (χ = 5.1, P = 0.17). All 3 Bordetella species, Bp, Bh and Bpp, were detected during on outbreak of pertussis-like cough illness. There were noted differences in age and seasonality, but clinical features at the time of presentation did not allow clear differentiation of these infections. All Bordetella species recovered from culture and tested were susceptible in vitro to macrolide antibiotics. Additional study is necessary to further characterize epidemiologic and clinical characteristics of Bh-associated cough illness and to determine potential co-occurrence of Bordetella species with other bacterial and viral respiratory tract pathogens.

Wheezing in Children With Pertussis Associated With Delayed Pertussis Diagnosis

The classic clinical features of paroxysmal pertussis are often absent in older children and adults and after vaccination. The California pertussis epidemic of 2010 occurred in a highly vaccinated population. All pediatric patients (0-18 years) with positive pertussis polymerase chain reaction from July to December 2010 were identified retrospectively from the Kaiser SCAL database. Information extracted by chart review included age at diagnosis, vaccine history, race, cough duration, number of clinic visits before diagnosis, presence of paroxysms, post-tussive emesis or wheezing, treatment for asthma during the course of illness and exposure to confirmed or suspected pertussis cases. Overall 501 pediatric patients (mean age = 8.4 years) with positive pertussis nasopharyngeal polymerase chain reaction were identified. Complete DTaP series and Tdap vaccine had been received by 93% and 38% of eligible patients, respectively. Paroxysms, post-tussive emesis and wheezing on physical examination were present in 34%, 30% and 8% of patients, respectively. Each was associated with a longer duration of symptoms at diagnosis. Wheezing was associated with a delay in diagnosis (60% requiring >1 clinic visit for diagnosis vs. 29% in the overall population, P < 0.0001). Documented exposures were associated with a more timely pertussis diagnosis (after 9.4 days vs. 14.5 days; P < 0.0001). Wheezing is present on examination of some patients with pertussis in a highly vaccinated pediatric population and appears to delay the diagnosis of pertussis. The presence of wheezing should not be used to exclude this diagnosis in children with chronic cough or other reasons to suspect pertussis.

Modifying the clinical case definition of pertussis increases the sensitivity of diagnosis in children suspected of Bordetella pertussis infection

Background: The WHO defines a surveillance clinical case of pertussis as one with a cough of at least 14 days duration and one of paroxysms, post-tussive vomiting or an inspiratory whoop. Laboratory confirmation is not essential for notification and remains unavailable in most of the developing world where current notification trends suggest that cases are being missed. We aimed to determine the sensitivity and specificity of changing the WHO’s clinical case definition in a cohort of children suspected of Bordetella pertussis infection. MethodsM 95% CI 1.5 – 3.3). Only 23/75 confirmed cases (31%) fulfilled the clinical case definition. The proportion of confirmed infections fulfilling case definition increased to 55% (41/75) when apnoea was added to theWHO definition. The sensitivity increased to 84% (58/75) when duration of cough was omitted from the definition. The specificity however declined from 88% to 56% with this modification. Conclusion: Modifying the WHO case definition of pertussis increases the sensitivity of pertussis clinical case detection. There is an urgent need to adopt a revised clinical case definition that takes into account the “atypical” clinical presentation in young and partially immunized children as well as limited access to laboratory diagnosis.

Epidemiological Aspects of Pertussis among Adults and Adolescents in a Korean Outpatient Setting: A Multicenter, PCR-Based Study

Epidemiological data of Bordetella pertussis infection among adolescents and adults are limited in Korea. Patients (≥ 11 yr of age) with a bothersome cough for less than 30 days were enrolled during a 1-yr period at 22 hospitals in Korea. Nasopharyngeal swabs were collected for polymerase chain reaction (PCR) and for bacteriologic culture. In total, 490 patients were finally enrolled, and 34 (6.9%) patients tested positive for B. pertussis; cough duration (14.0 days [7.0-21.0 days]) and age distribution were diverse. The incidence was the highest in secondary referral hospitals, compared to primary care clinics or tertiary referral hospitals (24/226 [10.6%] vs. 3/88 [3.4%] vs. 7/176 [4.0%], P = 0.012), and the peak incidence was observed in February and August (15.8% and 15.9%), with no confirmed cases between March and June. In the multivariate analysis, post-tussive vomiting was significantly associated with pertussis (odds ratio, 2.508; 95% confidence interval, 1.146-5.486) and secondary referral hospital showed a borderline significance. In conclusion, using a PCR-based method, 6.9% of adolescent and adult patients with an acute cough illness had pertussis infection in an outpatient setting. However, hospital levels and seasonal trends must be taken into account to develop a better strategy for controlling pertussis.Graphical

Clinical Manifestations of Children with Microbiologically Confirmed Pertussis Infection and Antimicrobial Susceptibility of Isolated Strains in a Regional Hospital in Japan, 2008^|^ndash;2012

We conducted a retrospective study in 57 children (median age, 3.5 years; range, 1 month-14.5 years) with microbiologically confirmed pertussis infection over a recent 4-year period in a regional hospital in Japan. We obtained nasal swabs from all patients for Bordetella pertussis isolation as well as performed B. pertussis DNA detection using loop-mediated isothermal amplification (LAMP). Of the 57 cases, 34 (60%) were culture-positive and 57 (100%) were LAMP-positive. The frequency of each symptom was as follows: typical paroxysmal cough for over 14 days, 96% (55/57); paroxysms, 86% (49/57); posttussive vomiting, 33% (19/57); inspiratory whoop, 25% (14/57); and apnea, 12% (7/57). Hospitalization was required in 14 cases (25%), 93% (13/14) of which were aged <1 year. The proportion of patients previously immunized against diphtheria-tetanus-acellular pertussis vaccine (DTaP) was 19% (4/21) in children aged <1 year and 92% (11/12) in children aged ≥ 10 years. Minimum inhibitory concentrations for 6 antimicrobials (erythromycin, clarithromycin, azithromycin, minocycline, amoxicillin, and sulfamethoxazole/trimethoprim) were measured for 30 isolated strains, and all strains were susceptible to all aforementioned antimicrobials. Thus, an additional pertussis vaccination in older children is necessary, and the current macrolides-based treatment strategy is considered reasonable.

To Compare the Effect of Dextromethorphan, Promethazine and Placebo on Nocturnal Cough in Children Aged 1–12 y with Upper Respiratory Infections: A Randomized Controlled Trial

To evaluate whether promethazine and dextromethorphan reduce nocturnal cough and improve sleep quality in children aged 1-12 y with upper respiratory tract infection (URI). This randomised double-blinded placebo-controlled trial was conducted in Pediatric outpatient department of Lok Nayak Hospital, Delhi. After randomization into promethazine, dextromethorphan and placebo groups, parental assessment of 120 children with URI for nocturnal cough severity (child), post-tussive vomiting (child) and sleep quality (child and parent) on the night before enrolment and after 3 d of assigned medication was measured using an internally validated indigenously prepared ordinal scale. Entire cohort improved in all the study parameters after 3 d. However, no superior benefit was noted when individual parameters were compared in the promethazine and dextromethorphan groups with the placebo group. Adverse effects were more frequent in the dextromethorphan and promethazine groups although the difference was not statistically significant. Nocturnal cough in URI is self-resolving and dextromethorphan and promethazine prescribed for the same are not superior to placebo.

Diagnostic value of symptoms and laboratory data for pertussis in adolescent and adult patients

BackgroundSeveral symptoms are classically thought to be suggestive of pertussis in children, but the diagnostic value of these symptoms in adolescent and adult patients is unclear. We evaluated the accuracy of the clinical findings for the early presumptive diagnosis of pertussis in adolescent and adult patients. Furthermore, we measured fractional exhaled nitric oxide (FeNO) with regard to whether we could distinguish eosinophilic inflammation of the airway and pertussis. FeNO is not expected to be associated with pertussis.MethodsWe compared 183 cases with laboratory-confirmed pertussis using serology and polymerase chain reaction and 1,132 cases without laboratory-confirmed pertussis.ResultsAmong pertussis patients, paroxysmal cough was common with 90% sensitivity, but the specificity was low (25%). Posttussive vomiting and whoop were less common (sensitivity 25% and 19%, respectively), but both showed greater specificity for pertussis (80% and 86%, respectively). Posttussive gagging was observed with intermediate frequency and provided greater specificity (49% and 77%, respectively). Pertussis cases were most frequent between May and August with a peak in June. The mean FeNO value for the pertussis patients was 18.2 ± 9.2 ppb, which was significantly lower than that in asthma patients (56.9 ± 20.3 ppb, p <0.001). The most useful definition was posttussive vomiting and/or gagging, and a plus normal FeNO value, which had a sensitivity of 72% and a specificity of 70%.ConclusionsClinical symptoms and laboratory data are of limited value in making the diagnosis of pertussis, and it was clinically difficult to differentiate adolescent and adult patients with or without pertussis. However, pertussis should be considered if patients have posttussive vomiting and/or gagging and a normal FeNO concentration.

Searching the B. pertussis (Real Time PCR) in Cases with Prolonged Cough (&gt;2 weeks) in Population with Unvaccinated Adult: A Cross Sectional Study. Tehran, Iran

Aims: searching the B. pertussis-DNAs by Real time PCR in nasopharyngeal samples of cases with prolonged cough (>2 weeks) in population with unvaccinated adult. Study design: A cross sectional/analytic study done in Rasoul Akram hospital (May 2007-March 2009); Tehran, Iran. Methodology: According to WHO criteria; 170 cases with cough (>2 weeks) with either paroxysm of cough, inspiratory whoop, or post-tussive vomiting and other cases with cough (in contact with the index case) selected for study. B.pertussis searched in nasopharyngeal samples by conventional and Real time- PCR. Results: Out of 170 studied cases (mean age 27.3 years). 34.3% had previous contact with other cases with prolonged cough. 50% was febrile. 67.6% presented with WHO criteria and 32.4% had not any other symptom except prolonged cough. Abnormal chest x-ray reported in 61.6%. Positive B.pertussis -DNAs detected in samples by conventional -PCR and Real time-PCR was 20% and 2.4% respectively. 2 cases with positive Real time-PCR were <6 month and 2 adults in contact with chronic cough children. Conclusion: Whooping cough caused by the bacteria B. pertussis and B.parapertussis. High false positive (20% and 2.4%) results by conventional PCR usually indicated to nasopharyngeal carriage state not B.pertussis disease so It is preferred to use Real time- PCR for definite diagnosis of B. pertussis in suspected cases. For disease prevention in adolescents and control the circulation of the organism, booster vaccination (with acellular pertussis vaccines) in older children, adolescents, and adults are needed.

Pertussis and Persistent Cough: Practical, Clinical and Epidemiologic Issues

BackgroundEpidemiologic issues of testing, treatment, prevention, immunization, mandated reporting, and post-exposure prophylaxis do not often intrude on the Emergency Department management of the well-appearing adolescent or adult with a couple of weeks of cough. ObjectivesConsidering that waning immunity to pertussis, the only vaccine-preventable disease with increasing cases and deaths in the United States, is responsible for 12–35% of such illness, such issues need to be considered. DiscussionMostly self-limited in adults, transmission of pertussis to infants places them at risk for hospitalization and death. Pertussis is highly contagious (80% transmission), and atypical presentations are the rule in adults (cough alone) and infants (apnea, bradycardia, poor feeding). Treatment in the first few weeks can impact the clinical course, and later treatment can still prevent transmission. Clinical features like paroxysmal cough, inspiratory “whoop,” and post-tussive emesis have mildly increased predictive values and may be absent in adults. Testing is unreliable after 3 weeks of cough. Treatment reduces communicability within 5 days and is suggested without regard to test results within 3 weeks of cough onset for those aged > 1 year (within 6 weeks of cough for < 1 year). Reporting requirements are based on the clinical case definition: ([Cough ≥2 weeks] + [paroxysms OR whoop OR post-tussive emesis]). Lower reporting thresholds are appropriate during an outbreak or when vulnerable populations are at risk. Post-exposure prophylaxis is recommended for at-risk contacts. Tdap is encouraged for all adults. ConclusionPractical recommendations consistent with the most current guidelines are offered.

Sinusitis and chronic cough in children

Background:Chronic cough in children is a common problem, and sinusitis is a common etiology. The diagnosis of sinusitis is often clinical, but confirmation is thought to require a CT scan due to the difficulty of interpreting a Water’s view sinus X-ray.Objectives:The purposes of the study were (1) to examine the frequency of an abnormal sinus X-ray in children with a chronic cough of more than 4 weeks duration; (2) to compare the interpretation of the sinus film between allergy/pulmonary clinicians and radiologists; and (3) to correlate symptoms with X-ray results.Methods:A chart review of 2- to 18-year-old patients with coughing exceeding 4 weeks was performed. Data was collected for patients who had received a Water’s view sinus film as part of their evaluation. Exam, X-ray results, and clinical outcomes were categorized and statistical analyses performed.Results:A total of 86 patients were included. Clinicians found that 65% of the children had positive Water’s view films, compared with the radiologist’s reading of 62% (non significant). Significant associations between post-tussive emesis (P = 0.01) and purulence (P = 0.03) were noted with a positive film. Positive sinus X-ray was highly associated with all findings except wheeze when present together (P < 0.001).Conclusion:Sinus abnormalities on X-ray are associated with prolonged cough in 65% of children. The Water’s view sinus film is a clinically useful screening tool for clinicians in the workup of chronic cough. Certain physical findings and clinical complaints, when present concurrently, correlate with the X-ray results.

The California Pertussis Epidemic 2010: A Review of 986 Pediatric Case Reports From San Diego County.

The California Department of Public Health (CDPH) declared a pertussis epidemic on 23 June 2010. More cases were reported in 2010 (9146) than in any year since 1947. We describe the characteristics of pertussis epidemiology and disease from 986 reported cases in children in San Diego County (population 3.2 million). Descriptive statistics were abstracted from CDPH pertussis case report forms that were completed by public health nurses investigating reports of positive laboratory results for pertussis and reports of illnesses compatible with pertussis. Of 1144 reported adult and pediatric cases, 753 (66%) were confirmed and 391 were probable/suspect. Children aged <19 years comprised 86% of all reported cases in San Diego County; of these, 22% were aged 11-18 years, 29% were aged 6-10 years, 27% were aged 1-5 years, and 22% were aged <1 year (with 70% aged <6 months). Case rates were highest in infants aged <6 months (651 per 100 000 population). Of those aged >1 year, the highest attack rates were in preschool children aged 1-5 years (114 per 100 000) and elementary school children aged 6-10 years (141 per 100 000). Of 51 children hospitalized, 82% were aged <6 months; 2 deaths occurred in these young infants. Paroxysmal cough was noted in over 70% of children in all age groups; post-tussive vomiting occurred in 36% (aged 11-18 years) to 57% (aged <6 months) of children. Pertussis vaccine efficacy may decrease more rapidly than previously believed, facilitating spread of pertussis in elementary school-aged children. The highest case rates and the only mortality occurred in infants aged <6 months.

Epidemiology of pertussis in a country with high vaccination coverage

Introduction Pertussis has been a preventable disease in Catalonia since 1965, but the annual number of cases remains high. The aim of this study was to analyze the epidemiology of pertussis in Catalonia and its implications for control purposes. Methods An epidemiological study was carried out in Catalonia between 2004 and 2008. Pertussis cases reported to the Department of Health were collected and disease reports were filled out with the case information. Incidence rates, rate ratios (RR) and their 95% confidence intervals (CI) were calculated. Results 963 cases were reported: 555 (57.6%) were confirmed and 408 (42.4%) were suspected cases. The reported incidence rate was 2.01 × 10 −5 person years in 2004 and 4.34 in 2008. The biggest increase in cases between 2004 and 2008 was observed in the ≥35 years age group (RR: 6.98; 95%CI: 2.11–36.36). 303 (31.5%) patients were hospitalized, of whom 93.7% were aged <1 year. Clinical differences were observed in paroxysmal cough (83.8% in suspected and 76.4% in confirmed cases, p = 0.005), posttussive vomiting (47.1% and 36.1%, respectively, p = 0.001), apnoea (13.7% and 21.3%, respectively, p = 0.003) and fever (20.1% and 12.4%, respectively, p = 0.001). Conclusion Pertussis incidence rates increased during the study period, with the greatest increase occurring in the ≥35 years age group. A booster dose of vaccine in young people could reduce the circulation of B. pertussis in adolescents and adults and indirectly reduce the incidence in children.

Posttussive emesis as a symptom of asthma in children

Emesis can be triggered by cough in children, and cough is a common symptom of asthma. To explore the association between posttussive emesis and asthma in the pediatric population. A questionnaire was distributed to parents of children between the ages of 2 and 17 years in the pediatric and allergy-immunology clinics at our institution from August 16 through November 3, 2008. Prevalence of posttussive emesis was determined and compared among children with physician-diagnosed asthma, children with no evidence of asthma, and those not formally diagnosed as having asthma but with surrogate markers suggestive of asthma. The predictive value of posttussive emesis was compared with those of known markers of asthma. The prevalence of gastroesophageal reflux and pertussis was evaluated because these conditions might also cause posttussive emesis. The prevalence of posttussive emesis was 33% in our study population of 500 children. Among those with physician-diagnosed asthma (n = 122), 56% reported a history of posttussive emesis. For patients not formally diagnosed as having asthma but with surrogate markers suggestive of asthma (n = 62), 71% had a history of posttussive emesis. Both of these were significantly higher than in those with no evidence of asthma (n = 316), in whom 16% reported a history of posttussive emesis (P < .0005). Children with posttussive emesis were significantly more likely to have asthma than those without posttussive emesis (odds ratio, 7.9; 95% confidence interval, 5.2-12). Neither pertussis nor gastroesophageal reflux accounted for the degree of posttussive emesis reported. Posttussive emesis is more common among children with asthma than among nonasthmatic children. In children with cough and a history of posttussive emesis, asthma should be strongly considered in the differential diagnosis.