Viral causes of acute respiratory infection among Egyptian children hospitalized with severe acute asthma exacerbation

Background: Viral respiratory infections are associated with nearly 80% of asthma exacerbation episodes. These can have severe adverse outcomes in patients with established asthma

Aim: The aim of the study was to identify the viral causes of acute respiratory infection that precipitate acute asthma exacerbation in Egyptian asthmatic children

Patients and methods: The current prospective study was conducted in Cairo University Children's Hospitals from December 2010 to December 2011. All asthmatic children [n=130] aged 2-12 years admitted with asthma exacerbation due to severe lower respiratory tract infection were included. All cases were subjected to nasopharyngeal or throat swabs that were analyzed for common respiratory viruses, including respiratory syncytial virus [RSV], human metapneumovirus [hMPV], influenza B [Flu B], human parainfluenza virus [hPIV], influenza A [H1N1], and adenovirus [ADV] using the real-time PCR technique. All patients were followed up to record the outcome

Results: PCR analysis was positive for one respiratory virus in 54 asthmatic patients [41.5%] and was negative in 76 patients [58.5%], with a high predominance of RSV [51.9%] and hMPV [25.9%] especially in winter and early spring months. Hypoxia was detected in all patients with RSV infection; of these patients, 21.4% were admitted to the ICU, 14.3% required mechanical ventilation, and 14.3% died. In contrast, among those with hMPV infection, hypoxia was detected in 71.4%; none required ICU admission or mechanical ventilation

Conclusion and recommendations: Viral etiology of lower respiratory tract infections constitutes an important cause of acute asthma exacerbation in asthmatic children admitted to children's hospitals in Cairo, supporting the need for large-scale multicentric studies on asthmatic patients over multiple years using a wider-panel PCR for detection of respiratory viruses

Effect of the pattern of colonization of the maternal genital tract at the time of delivery on early onset neonatal sepsis

Early onset neonatal sepsis increases significantly in the presence of vaginal and cervical colonization with pathogenic organisms. The aim of this study was to study the effect of the pattern of colonization of the maternal genital tract at the time of delivery on early onset neonatal sepsis. A prospective clinical study was conducted in Cairo University Hospitals on 352 pregnant women coming for delivery and their newborns. Vaginal swabs were taken from the mothers before first vaginal examination [PV] and just before delivery. Surface swabs from the body of babies were taken. The neonates were clinically evaluated and prospectively followed up in the first week of their life for clinical evidence of sepsis and blood cultures were done for clinically septic neonates. Swabs were taken from different environmental sources in the Obstetric and Neonatology wards. Microbiological typing was conducted by biotyping and antibiogram to prove the similarity between microorganisms isolated from maternal or environmental sources and the corresponding neonates. Pulsed field gel electrophoresis was used for genotyping of phenotypically similar isolates. Microbiological similarity between culture results of mothers and their newborns was proven in 86% of cases. The correlation between clinical sepsis and microbiological agreement was also highly significant [p value=0.001]. Positive vaginal swab cultures were highly predictive of positive blood culture [p-value=0.09]. We found that, multiple vaginal examinations [more than 3 times] was the most frequent maternal risk factor of neonatal bacteremia [p-value=0.049]. Contamination of environment [gel and gloves] and equipment [suction sets] used for mothers and their babies during delivery was probably an important source of microorganisms. Maternal colonization and the contaminated environment were important risk factors for neonatal sepsis. Hence, limitation of PV and strict infection control measures should be followed in delivery room

Comparison of polymerase chain reaction, culture and serology testing for detection of Bordetella pertussis in children

The aim of this study was to perform a PCR technique on naso- pharyngeal swabs to detect BP in 59 children suffering from protracted cough lasting for at least two weeks and to compare the performance of three different techniques for diagnosis of BP; PCR, culture on Bordet Gengou agar and serological assays of IgM, IgA and IgG antibodies to FHA by enzyme immunoassay test. Three patients out of 59 [5.1%] were positive for B. pertussis by both PCR and culture methods. Eleven cases were positive for IgA antibodies compared to seven cases positive for IgA and only one by IgM. Serum IgA and IgG antibodies results showed highly significant correlation with results of culture and PCR, but no significant difference was found with IgM results. In conclusion, PCR was found to be an accurate and rapid method for detection of B. pertussis compared to culture method. The results of IgA and IgG antibody tests showed highly significant correlation to culture and PCR results