The prevalence and clinical malignant fibrous histiocytoma mri characteristics of pertussis-associated pneumonia among infants in botswana bmc pediatrics full text

Pertussis is a respiratory illness most commonly caused by Bordetella malignant fibrous histiocytoma mri pertussis. The disease is classically divided into catarrhal, paroxysmal, and convalescent stages. The paroxysmal stage is classical of pertussis and manifests as malignant fibrous histiocytoma mri intense bouts of coughing which may be interrupted by a malignant fibrous histiocytoma mri high-pitched “whoop” as the child rapidly inhales. However, paroxysmal cough may be absent in young infants, and pertussis disease in infancy can be complicated by apnea, convulsions, and death [ 1].

The burden of pertussis disease in low- and middle-income countries (LMICs) is difficult to estimate and poorly recorded. This may be due to the limited availability of diagnostic malignant fibrous histiocytoma mri assays for B. pertussis detection and under recognition of pertussis infection that is malignant fibrous histiocytoma mri not associated with classical clinical features [ 2]. Several factors that might affect the risk and severity of malignant fibrous histiocytoma mri pertussis disease among infants merit special consideration in LMICs. Of particular concern is maternal human immunodeficiency virus (HIV) infection, which is estimated to affect nearly one-third of pregnancies in Botswana and several other countries in malignant fibrous histiocytoma mri sub-Saharan Africa [ 3]. HIV-exposed uninfected (HEU) infants are at higher risk of severe infections [ 4] and have lower anti-pertussis antibodies at birth than the infants of HIV-negative mothers (HIV-unexposed uninfected; HUU) [ 5].

There are scant data on the prevalence and clinical course malignant fibrous histiocytoma mri of pertussis among infants with pneumonia in LMICs because most malignant fibrous histiocytoma mri studies selectively enrolled infants with clinical symptoms classically associated with malignant fibrous histiocytoma mri pertussis (e.g., whooping cough). As infants and young children with pertussis disease often do malignant fibrous histiocytoma mri not manifest these classical symptoms, restricting recruitment to patients with these symptoms has likely led malignant fibrous histiocytoma mri to underestimation of pertussis disease prevalence. Furthermore, immunization against pertussis in pregnancy is being implemented in an malignant fibrous histiocytoma mri increasing number of countries, with the primary goal of preventing classical pertussis disease among malignant fibrous histiocytoma mri young infants [ 6]. However, an additional benefit of maternal pertussis immunization programs may be malignant fibrous histiocytoma mri the reduction of pneumonia caused by pertussis. Thus, data on the prevalence and clinical course of pertussis-associated pneumonia are important in settings where immunization against pertussis malignant fibrous histiocytoma mri during pregnancy is being considered.

The study population was previously described in detail [ 7]. Briefly, we recruited children 1–23 months of age presenting with pneumonia at Princess Marina malignant fibrous histiocytoma mri Hospital in Gaborone, Botswana between April 2012 and June 2016. We defined pneumonia per World Health Organization (WHO) clinical criteria as “cough or difficulty in breathing with lower chest wall indrawing” [ 7]. We excluded children with chronic medical conditions predisposing to pneumonia malignant fibrous histiocytoma mri (except HIV infection), hospitalization within the previous 14 days, a diagnosis of asthma, or wheezing with resolution of chest wall indrawing after ≤2 treatments with a bronchodilator. Whole-cell pertussis (wP) vaccine is used for primary and booster immunization of infants malignant fibrous histiocytoma mri and children in Botswana, with the primary series being administered at 2, 3, and 4 months of age. Women were not routinely immunized for pertussis during pregnancy in malignant fibrous histiocytoma mri Botswana throughout the study period. Laboratory methods

We obtained nasopharyngeal swab specimens from all children at enrollment malignant fibrous histiocytoma mri using flocked swabs and universal transport media (Copan Italia, Brescia, Italy). Specimens were stored at − 80 °C, shipped on dry ice at 6-month intervals to the Regional Virology Laboratory (St. Joseph’s Healthcare, Hamilton, ON, Canada), and tested for respiratory viruses using PCR [ 7]. In the analyses presented herein, we used a previously validated highly sensitive and specific in-house real-time PCR assay that detects a unique sequence of the malignant fibrous histiocytoma mri porin gene of B. pertussis [ 8].

B. pertussis was detected from only 1% of children less than 2 years of age with pneumonia malignant fibrous histiocytoma mri in Botswana. However, among infants 1–5 months of age with pneumonia, the prevalence of B. pertussis was 2%, including a prevalence of approximately 5% among HEU infants in this age group. Pertussis-associated pneumonia was not associated with mortality in the few malignant fibrous histiocytoma mri cases observed in this cohort. This study provides important data on the prevalence and clinical malignant fibrous histiocytoma mri outcome of pertussis-associated pneumonia among infants and young children in a LMIC malignant fibrous histiocytoma mri setting where surveillance for pertussis disease is lacking and wP malignant fibrous histiocytoma mri vaccine is used for routine childhood immunization against pertussis.

The prevalence of B. pertussis among infants 1–5 months of age with pneumonia in this study is malignant fibrous histiocytoma mri similar to the prevalence among infants 1–5 months of age (2.6%; 40/1547) and HEU infants aged 1–5 months of age (4.7%; 12/256) hospitalized with severe or very severe pneumonia in multiple African malignant fibrous histiocytoma mri countries (The Gambia, Kenya, Mali, South Africa, Zambia) in the Pneumonia Etiology Research for Child Health (PERCH) Study [ 9]. Our results are also similar to a study conducted in malignant fibrous histiocytoma mri South Africa, where the prevalence of B. pertussis was 2.3% (42/1839) among infants  20,000 cells/μL) than infants with pneumonia who tested negative for pertussis [ 9].

Antibiotic treatment is indicated for all cases of pertussis, regardless of the clinical presentation or the severity of the malignant fibrous histiocytoma mri illness. While treatment of pertussis early in the course of the malignant fibrous histiocytoma mri disease is more likely to ameliorate symptoms than treatment later malignant fibrous histiocytoma mri in the disease course [ 24], an additional benefit of treatment of pertussis disease is the malignant fibrous histiocytoma mri reduction of person-to-person transmission [ 25, 26, 27]. Interrupting transmission is an important public health benefit because there malignant fibrous histiocytoma mri is high prevalence of subclinical or mild infections among household malignant fibrous histiocytoma mri contacts of pertussis cases, which may play a critical role in the maintenance of malignant fibrous histiocytoma mri ongoing transmission of pertussis [ 27].

Immunization against pertussis in pregnancy has been shown to decrease malignant fibrous histiocytoma mri the risk of pertussis infection and the severity of pertussis malignant fibrous histiocytoma mri disease among young infants [ 28, 29]. An additional benefit to pertussis immunization in pregnancy may be malignant fibrous histiocytoma mri the prevention of illnesses that are not classically associated with malignant fibrous histiocytoma mri pertussis. Given that pertussis vaccination in pregnancy is highly effective (~ 85% efficacy) in preventing pertussis disease among young infants [ 29], it is also reasonable to anticipate that the majority of malignant fibrous histiocytoma mri pertussis-associated pneumonia cases in this study could have been prevented malignant fibrous histiocytoma mri by pertussis immunization in pregnancy.

This study has a number of strengths. B. pertussis was tested for in a large number of infants malignant fibrous histiocytoma mri with pneumonia in an African country with long-standing high uptake of the wP vaccine. The study was prospective and conducted over 5 years, thus minimizing the possibility that seasonal variation and the cyclical malignant fibrous histiocytoma mri pattern of pertussis might influence the results. This study also has several important limitations. It was conducted at a single referral center and the malignant fibrous histiocytoma mri results may not be generalizable to non-tertiary care centers. Furthermore, patients with more severe pneumonia may have died before admission malignant fibrous histiocytoma mri to hospital, and consequently some cases of pertussis may have been missed. The small sample size of HIV-infected infants limits our ability to draw definitive conclusions about malignant fibrous histiocytoma mri the prevalence of B. pertussis among infants with pneumonia in this population. Finally, the study did not include infants < 1 month of age, an age group that is highly susceptible to severe pertussis malignant fibrous histiocytoma mri infection.

This research was supported by an European Society for Paediatric malignant fibrous histiocytoma mri Infectious Diseases Small Grant Award (to BA), an Early Career Award from the Thrasher Research Fund (to MSK), a Burroughs Wellcome / American Society of Tropical Medicine and Hygiene Postdoctoral Fellowship in malignant fibrous histiocytoma mri Tropical Infectious Diseases (to MSK), and through core services from the Penn Center for AIDS malignant fibrous histiocytoma mri Research, a National Institutes of Health (NIH)-funded program (P30-AI045008) and the Duke CFAR ( 5P30 AI064518). Funding for this project was also made possible in part malignant fibrous histiocytoma mri by a CIPHER grant (to MSK) from the International AIDS Society, supported by ViiV Healthcare. The views expressed in this publication do not necessarily reflect malignant fibrous histiocytoma mri the official policies of the International AIDS Society or ViiV malignant fibrous histiocytoma mri Healthcare.

The funding bodies had no role in study design, data collection, analysis, and interpretation, or writing the manuscript. BA is supported by the Canadian Health and Research Institute malignant fibrous histiocytoma mri Vanier Canada Graduate scholarship. MSK was supported by a NIH Career Development Award (K23-AI135090). MSa is supported via salary awards from the BC Children’s Hospital Foundation, the Canadian Child Health Clinician Scientist Program and the Michael malignant fibrous histiocytoma mri Smith Foundation for Health Research.

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