Mycoplasma pneumoniae and Chlamydophila pneumoniae in children with community-acquired pneumonia in Thailand.

BACKGROUND: The prevalence of community-acquired pneumonia (CAP) caused by atypical pathogens in Thai children is unknown. OBJECTIVE: To examine the prevalence of Mycoplasma pneumoniae and Chlamydophila pneumoniae infections in paediatric patients (aged 2-15 years) with CAP in three academic hospitals using standardised laboratory techniques. The characteristics of atypical pneumonia were also compared with other causes of CAP. METHODS: Diagnosis of current infection was based on a four-fold or more rise in antibody serum samples or persistently high antibody titres together with the presence of mycoplasmal or chlamydial DNA in secretions. RESULTS: Of 245 patients with CAP, 17.5% of cases were caused by atypical pathogens (M. pneumoniae 14.3%, C. pneumoniae 2.8% and co-infection 0.4%). We also found atypical pathogens in young children aged 2-5 years. The clinical and laboratory findings did not distinguish atypical pneumonia from other CAPs. Segmental or lobar consolidation on chest X-rays was more common in atypical pneumonia, while dyspnoea was more prominent in other CAPs. CONCLUSION: Our data show a high prevalence of M. pneumoniae and C. pneumoniae in Thai children with CAP, including in children aged 2-5 years.

Can parents predict the severity of childhood obstructive sleep apnoea?

OBJECTIVE: To determine whether parents' observations can be used to predict the severity of the obstructive sleep apnoea syndrome (OSAS) in children. STUDY DESIGN: Sixty-five children with OSAS diagnosed by overnight polysomnography were consecutively recruited and classified as having severe or non-severe OSAS according to the obstructive apnoea index (OAI) and the oxygen saturation measured by pulse oximetry (SpO2) nadir. Parents were asked to complete a questionnaire about the child's breathing difficulties at night. RESULTS: Twenty-eight patients were classified as severe OSAS and 37 as non-severe OSAS. There were no differences between the two groups with respect to age, sex or body mass index. Male to female ratio was 5:1. Parents of children with severe OSAS more frequently reported observed cyanosis (35 vs 8%; p=0.02); obstructive apnoea (60 vs 35%; p = 0.04); snoring extremely loudly (52 vs 22%; p = 0.01); shaking the child (64 vs 35%; p = 0.02); watching the child during sleep and being afraid of apnoea (85 vs 60%; p = 0.03). However, neither any single nor combinations of observations showed high values for both sensitivity and specificity. CONCLUSIONS: Although some parents' observations are more frequently reported in children with severe OSAS, neither any single nor combinations of observations accurately predict the severity of OSAS. Polysomnography is still needed to determine the severity of obstruction.

Prone position in spontaneously breathing infants with pneumonia.

This study was designed to evaluate further the effect of prone positioning on oxygen saturation (SpO2) and respiratory mechanics in spontaneously breathing infants with pneumonia. SpO2 and respiratory mechanics were measured in the supine and prone positions in 17 infants. Prone positioning resulted in statistically significant increases in mean (+/- SD) SpO2 (95.52+/-2.87 to 98.00+/-2.40%, p = 0.0002) and respiratory system compliance (5.99+/-2.52 to 7.93+/-4.30 ml/cm H2O, p = 0.02). This suggests that prone positioning is another beneficial supportive measure for spontaneously breathing infants with pneumonia.

Pulmonary involvement in childhood systemic lupus erythematosus.

Twenty-four children (aged 6-15 years, M:F = 1:11) with systemic lupus erythematosus (SLE), who had respiratory symptoms, were retrospectively reviewed. Chest radiographs obtained from all patients revealed pleural effusion in 13, alveolar infiltration in 9, pericardial effusion and cardiomegaly in 6, interstitial infiltration in 4, hilar adenopathy in 3, lung abscess in 2 and pneumatocele with pneumothorax in 1. Etiologic organisms were identified in 7 cases; (3 cases of nocardia isolated from pleural effusion and sputum, 2 cases of tuberculosis, 1 case with staphylococcus aureus septicemia and 1 case with salmonella septicemia). All except one patient improved with medical treatment. One patient died from pneumonitis. Although pulmonary involvement is increasingly recognized in children with SLE, neither roentgenogram nor clinical findings were specific. The differentiation of pulmonary infiltrates caused by lupus lung disease from pulmonary infection should be carefully evaluated.

Pulmonary function and exercise challenge test in Thai children: 10 years post respiratory syncytial virus infection.

OBJECTIVE: To report the occurrence of asthma, pulmonary function and exercise challenge test abnormalities found in Thai children, who 10 years earlier had lower respiratory tract infection caused by respiratory syncytial virus (RSV-LRI). PATIENTS AND METHODS: 37 children, with RSV-LRI admitted at Ramathibodi Hospital during January 1986 through December 1987, were contacted, of whom 13 patients responded and completed history-review-questionnaires. Pulmonary function measurements at pre- and post-exercise and testing for bronchodilator response were performed. RESULTS: The occurrence of physician-diagnosed asthma in the patients with and without family history of allergic diseases was 75 per cent and 40 per cent, respectively. Of 11 patients who performed spirometry, 45 per cent had concave flow-volume curves, 36 per cent showed decreased ratio of forced expiratory flow in the first second (FEV1) to forced vital capacity (FVC) and 27 per cent showed either decreased forced expiratory flow between 25-75 per cent of FVC (FEF25-75%) or peak expiratory flow rate (PEFR). Of 8 patients who completed exercise challenge tests, 87.5 per cent showed markedly decreased PEFR at post exercise challenge tests and 37.5 per cent had markedly decreased FEV1. 62.5 per cent and 25 per cent showed markedly increased PEFR and FEV, respectively, after inhalation of bronchodilators. CONCLUSION: This study suggests that the occurrence of asthma in children, who had previous RSV-LRI, is relatively high compared with that reported in general Thai children. Baseline pulmonary function tests showed evidence of airway obstruction as demonstrated by concave-shaped flow-volume curves, decreased FEV1/FVC ratio, FEF25-75% and PEFR. The presence of bronchial hyperreactivity to exercise challenge test and positive response to bronchodilators confirms the evidence of exercise-induced bronchospasm in children with history of RSV-LRI.

Cyanide poisoning, 2 cases report and treatment review.

Two patients, a 4-year-old girl and her brother 1 1/2 year-old, with cyanide poisoning are reported. They vomited and became comatose 9 hours after ingestion of boiled cassava. At a community hospital, they were intubated and given ventilatory support. The girl was transferred to Ramathibodi Intensive Care Unit. At 19 hours after ingestion, sodium nitrite and sodium thiosulfate were given as well as other supportive treatment. She recovered with normal breathing on the next day. The boy was referred to Ramathibodi 4 hours later. On arrival, he appeared normal except for the bitter almond breathe. Only supportive treatment was given. Their blood cyanide levels on arrival were 0.56 and 0.32 microgram/ml (normal value < 0.3 microgram/ml) respectively confirming the diagnosis of cyanide poisoning. Other abnormal laboratory findings included metabolic acidosis and lactic acidemia. The pathogenesis and management of cyanide poisoning are reviewed.

Case report of a Thai male cystic fibrosis patinet with the 1898+ 1G-->T splicing mutation in the CFTR gene: a review of East Asian cases. Mutations in brief no. 196. Online.

Cystic fibrosis (CF) is the most common fatal autosomal recessive multisystem disorder, which occurs mainly in European-derived populations. The incidence of CF varies between 1 in 2000 to 3000 live-births in various ethnic groups. The disease is rare in East Asians. Here we report a 9 year old Thai male patient, who was diagnosed to have CF based on recurrent pneumonia, a slow weight gain, pancreatic insufficiency and repeatedly elevated sweat chloride levels by two different methods. A comprehensive genetic analysis showed the splicing mutation, 1898+ 1G-->T, which was apparently of maternal origin. Literature search found 39 documented cases of CF patients in East Asians. CFTR (MIM# 602421) genotyping was performed in 14 patients including our patient and in 9 of them a CF allele was identified. The findings seem to indicate that the splicing mutations, 1898+ 1G-->T and 1898+ 5G-->T are more common in East Asian CF patients.

Randomized controlled trial of dexamethasone in infectious croup.

Infectious croup is a common and an important cause of upper airway obstruction in young children. Despite its frequency and potentially serious nature, there is still no definite conclusion regarding the beneficial effect of corticosteroid. A randomized controlled study on the effects of dexamethasone in infectious croup was conducted at the Department of Pediatrics, Ramathibodi Hospital between January 1985 and September 1986. Thirty-two patients, 2-37 months old, were included in this study. Fourteen patients received dexamethasone (0.5 mg/kg/dose daily for 3 days) and eighteen patients were the control group. The dexamethasone group had significantly lower croup scores at 48 hour (p < 0.05), shorter hospital course (p < 0.005) and lower incidence of endotracheal intubation (p < 0.05) than the control group. Five patients in the control group required endotracheal intubation. Complications included four episodes of pneumonia, one episode of sepsis, and one bacterial tracheitis. Pneumonia and sepsis occurred only in the control group. We concluded that dexamethasone therapy decrease the severity of infectious croup and the risk of complications.

Obstructive sleep apnea syndrome in Thai children diagnosed by polysomnography.

Overnight polysomnography was conducted in 39 Thai children with clinically suspected obstructive sleep apnea syndrome (OSAS) during the years 1994 to 1996. Eighty-five percent of these children met the polysomnographic criteria of pediatric OSAS, 42.4% among whom had severe OSAS. Male : female ratio of children with OSAS was 4.5:1. The peak age at the time of diagnosis was 3 to 4 years. The most common predisposing factor was adenoidal and tonsillar hypertrophy. Adenoidectomy and/or tonsillectomy was the most effective therapeutic option. Recovery of symptoms was observed following surgery and nasal continuous positive airway pressure.

Incidence of Mycoplasma pneumoniae, Chlamydia trachomatis, and viral infections in pneumonia cases under six months of age, Bangkok, Thailand.

The incidence of infections by Mycoplasma pneumoniae, Chlamydia trachomatis and respiratory viruses was investigated in 76 pneumonic patients aged under 6 months who attended Ramathibodi and Siriraj Hospitals in Bangkok during two study periods. M. pneumoniae infection was not found in any case from either hospital by serological diagnosis. By the isolation method, C. trachomatis infection was found in 7(16.7%) of 42 patients from Ramathibodi Hospital and 5(21.7%) of 23 patients from Siriraj Hospital with the average male:female ratio of 2.6:1; and 91.7% of the infected cases were under 3 months old. Laboratory diagnosis of respiratory virus infection was performed by indirect immunofluorescence (IIF), isolation, and by antibody detection. Data from Ramathibodi Hospital showed that 11 (24.4%), 4 (8.9%), 3 (6.7%) of the 45 patients were infected by respiratory syncytial virus (RSV), adenoviruses, parainfluenza virus type 3, and some other viruses, respectively; infection rates of 10 (32.3%), 4 (12.9%), 1 (3.2%) and 1 (3.2%) by those viruses respectively, were observed in the 31 patients from Siriraj Hospital.

Risk factors associated with morbidity and mortality of pneumonia in Thai children under 5 years.

ARI is the most common cause of illness and death in children under 5 years of age. Pneumonia is the leading cause of death. This prospective study was part of an ARIC project conducted to identify risk factors associated with mortality and morbidity of community acquired pneumonia in Thai children younger than 5 years of age. Study subjects were 267 moderately severe pneumonia who were admitted to hospital. Fifteen percent required a ventilator and were categorized as severe cases. Nine patients (3.4%) died and were categorized in the fatal group. From univariate analysis only, risk factors of fatal pneumonia were lower body weight (p = 0.04), paternal age less than 35 year (OR = 6.1, p = 0.01), underlying heart disease (OR = 12.1, p = 0.0000) and protein energy malnutrition (OR = 7.9, p = 0.0087). Predictors on admission to predict fatal outcome were rapid respiratory rate > 50/minute (OR = 4.1, p = 0.03), gallop rhythm (OR = 11, p = 0.04), enlarged liver (OR = 13.2, p = 0.001), and cyanosis (OR = 12, p = 0.0006). Significant factors associated with severe pneumonia after multiple logistic regression were underlying heart disease (OR = 4.04, 95% CI 1-15.4), enlarged liver (OR = 4.31, 95% CI 1.2-15.2) and cyanosis (OR = 5, 95% CI 0.8-28.7). This information should create awareness in physicians who are responsible for young children with pneumonia. Early recognition and intervention may prevent deaths and complications.(ABSTRACT TRUNCATED AT 250 WORDS)

Correlation of roentgenologic diagnosis and etiologic agents of pneumonia in thai children under 5 years of age.

An attempt to distinguish between viral and bacterial pneumonia from radiographs is usually difficult unless there is a pathognomonic type of infiltration such as parahilar peribronchial infiltration commonly seen in viral pneumonia which can be usually be differentiated easily from that of bacterial pneumonia. Percentage of agreement of roentgenographic diagnosis for bacterial pneumonia, viral pneumonia and mixed infection is about 53, 73.3 and 63.9 per cent respectively.

Pulmonary and platelet function in mild form of Hb H disease.

Pulmonary function abnormality, arterial hypoxemia and platelet hyperaggregation were commonly seen in severe or moderately severe thalassemic patients. In previous studies, these abnormalities were found in beta-thalassemia, beta-thalassemia/Hb E disease and Hb H disease in 62, 40 and 52%, respectively. However these functional abnormalities in mild form of Hb H disease have not yet been reported. Pulmonary function test by using standard spirometry, platelet aggregation and arterial blood gases were performed in 23 children with mild form of Hb H disease, whose age ranged from 6-18 years (average 11 years), and hematocrit status was 30-40%. Mild to moderate degree of restrictive lung disorder was found in 48% of these patients, 5% had mild platelet hyperaggregation and none of these had arterial hypoxemia. This study showed that a pulmonary function defect was noted as one significant finding in thalassemic patients, being noted even in the very mild form and early age of life. This information will lead to further exploration of the pathogenesis of pulmonary function defects as well as their role is the patients' future health and prognosis.

Protective efficacy of neonatal Bacillus Calmette-Guérin vaccination against tuberculosis.

This matched case-control study was performed in two hospitals in Bangkok to evaluate the protective efficacy of neonatal Bacillus Calmette-Guérin (BCG) vaccination in Thai children and to find factors that might explain the reported variation in estimates of the protective efficacy of BCG. Cases were defined as children 3 months to 14 years of age who had tuberculosis and controls consisted of one to four children who were born in the same year and had the same district of residence as the case. A matched analysis with a variable number of controls per case was performed on 75 cases and 207 controls. Conditional logistic regression was performed to adjust for the potential confounding effects of household tuberculosis exposure and socioeconomic status. Forty-eight percent of cases had nonrespiratory tuberculosis. Laboratory-confirmed evidence for tuberculosis was found in 48% of cases. The adjusted protective efficacy of neonatal BCG vaccination was 83% (95% confidence limits, 35%, 96%). It was 96% (95% confidence limits, 66%, 100%) when only 36 matched sets of laboratory-confirmed cases were analyzed. Subgroup analyses and literature reviews indicated that the accuracy of tuberculosis diagnosis, types of tuberculosis, duration after vaccination and household tuberculosis exposure contribute to variation in the reported protective efficacy of neonatal BCG vaccination.

A community-based study of acute respiratory tract infection in Thai children.

A 2-year longitudinal study was conducted among the population of a socioeconomically depressed urban community in Bangkok, Thailand, from January 1986 through December 1987 to determine the incidence, etiologic agents, and risk factors associated with acute respiratory tract infection (ARI) in children less than 5 years of age. Data were obtained for a total of 674 children, who were visited twice weekly for detection of signs and symptoms of ARI. During the first year of the study, throat-swab specimens were obtained for bacterial culture from both ill and healthy children and a nasal wash was performed on mildly ill children for detection of virus. During both years of the study, nasopharyngeal aspiration for identification of virus was performed for children with more severe infection. The overall incidence of ARI was 11.2 episodes per child-year. The highest (14.9) and lowest (8.8) rates per child-year occurred in age groups 6-11 months and 48-59 months, respectively. Respiratory syncytial virus, parainfluenza virus, adenovirus, Streptococcus pneumoniae, and Haemophilus influenzae were the prevalent pathogenic agents identified. Factors associated with higher risk of ARI were low family income, working mothers, mothers with allergies, chronic malnutrition, and crowding in the home.