A Case ofEscherichia Coli Empyema Preceded by Gastroenteritis / 소아알레르기및호흡기학회지

Pleural empyema is characterized by presence of pus or microorganism in the pleural fluid. Most cases of empyema in children are caused by bacterial pneumonia, and the most common pathogen is Staphylococcus areus or Streptococcus pneumoniae. But other uncommon causes of empyema include esophageal rupture, mediastinal disease, tumors, sepsis, thoracic trauma, and surgery can be produced by various pathogens. We experienced a case of Escherichia coli empyema followed by gastroenteritis in 9-year-old boy.

Correlation between the Diagnostic Validity of Enzymeimmunoassay and the Hyperreactivity of the Respiratory Tract for the Diagnosis of Mycoplasma pneumoniae / 소아알레르기및호흡기학회지

PURPOSE:Mycoplasma pneumoniae (M. pneumoniae) is one of the common causes of lower respiratory tract diseases. Several studies have suggested that respiratory infection by M. pneumoniae may be associated with a reactive airway disease and asthma. In order to find such relationships, we compared the particle agglutination test with enzyme immunoassay (EIA) which were checked on the 1st, and at 1 and 5 or 7 days of follow-up. We also evaluated EIA in association with bronchial hypersensitivity. METHODS:One hundred eleven children who were out patients or hospitalized with pneumonia at Inje University and Hallym University Hospitals were included in the study. Patients were grouped according to the M. pneumoniae antibody titer. Patients who showed initial M. pneumoniae antibody titer and EIA Immunoglobulin (Ig) G/IgM greater than 1:320 were designated as group 1 (n=46). In group 2 (n=33), patients showed initial M. pneumoniae antibody titer lower than 1:320 but it increased more than fourfold between acute and convalescent stages. Group 3 (n=32) was a control group. We measured eosinophil counts, the total IgE, and the eosinophil cationic protein (ECP). Thirty-five children were checked with the methacholine test 3 or 4 months, after the first visit. Bronchial hypersensitiveness was defined positive if the concentration of methacholine was less than the lower limit (8 mg/mL methacholine). RESULTS:All 111 patients participated in the particle agglutination test at the initial and convalescent stages. The sensitivity and specificity for EIA were obtained from the results of the particle agglutination test. The sensitivity and specificity of acute and convalescent EIA IgG were 44.3% and 90.6%, and 67.1% and 96.9%, respectively. The sensitivity and specificity of acute and convalescent EIA IgM were 60.8% and 100%, and 92.4% and 100%, respectively. The M. pneumoniae antibody titer was associated with hospitalized days and improvement of chest X-rays. Only in group 3, the M. pneumoniae antibody titer correlated with the ECP level, but there was no significant difference between the methacholine test and eosinophil counts. CONCLUSION:The results of this study suggest that EIA may be a useful diagnostic method for detecting early phase of M. pneumoniae infection.

Clinical Significance of Follow-up CT after Ultrasonographyfor Acute Appendicitis in Children / 대한소아소화기영양학회지

PURPOSE: The ultrasonography (USG) and computed tomography (CT) are popular diagnostic tools for the diagnosis of acute appendicitis in children, but there are many debates about their clinical significance. The purpose of this study is to clarify the clinical significance of USG, CT and follow-up CT performed subsequently to USG, especially in perforated acute appendicitis in children. METHODS: We have reviewed 419 cases of surgically confirmed acute appendicitis in children under the age of sixteen, who had been treated in Inje University Ilsan Paik Hospital from March 2002 to February 2006. All the clinical data including the results of USG and CT were collected and analyzed. RESULTS: Sensitivity, specificity, positive and negative predictive values of USG were 98.7%, 96.8%, 98.1%, 97.8% in non-perforation group and 90.8%, 100%, 100%, 81.9% in perforation group. Those of CT were 96.4%, 100%, 100%, 96.5% and 86.6%, 100%, 100%, 87.5% respectively. Those of follow-up CT after USG were 100%, 100%, 100%, 100% and 87.5%, 100%, 100%, 92.0% respectively. The duration of using antibiotics in seven patients showed positive correlation with the interval between two imaging studies (r=0.0472, p=0.019). There was no statistical significance of correlation when these imaging studies performed within 30 hours together. CONCLUSION: In most of the cases, single choice between USG and CT would be enough to diagnose the acute appendicitis in children. But, it may be helpful to perform CT as early as possible subsequently to USG when there is discrepancy between initial USG and clinical impression.

Etiology of Community-acquired Bacteremia in Healthy Children / 소아과

PURPOSE: A full view of the spectrum of all bacterial diseases in healthy children is essential to the establishment of public health priorities. Accurate information on the relative importance of the various pathogens in terms of the age of the affected patients, the site of infection and the case fatality rate are valuable to the clinician in choosing antimicrobial treatments. METHODS: Fifty-nine episodes of bacteremia were analysed. Data were collected at Ilsan Paik Hospital from January 2000 to December 2003. Analysis of each collected episode included isolating pathogen from blood culture, diagnosis, hospital course, isolating pathogens from other tissue sites, and studying results of antimicrobial sensitivity tests. RESULTS: Fifty-nine cases of community-acquired bacteremia were reviewed. The most common pathogen was Staphylococcus aureus (11 cases, 18.6 percent), followed by Salmonella (10 cases, 16.9 percent), E. coli (7 cases, 11.9 percent), Streptococcus pneumoniae (five cases, 8.5 percent), Streptococcus viridans (5 cases 8.5 percent). The most common diagnosis was bacteremia without an indentified focus (61 percent), followed by meningitis (12 percent), bacteremia with enteritis (10.2 percent) and bacteremia with urinary tract infection (8.5 percent). Salmonella was still an important causative agent of bacteremia. The relative importance of Haemophilus influenza and Streptococcus pneumoniae was lower than in other studies. The most common organism responsible for bacteremia without an identified focus was Staphylococcus aureus The case-fatality was 3.4 percent for all cases of bacteremia. CONCLUSION: We reviewed the etiology of community-acquired bacteremia. These data may be useful in the establishment of public health priorities and serve as a reference for selection of antibiotics in the empirical therapy of suspected invasive bacterial infection.

Prevalence of Allergic Disease in Kindergarten Age Children in Korea / 소아알레르기및호흡기학회지

PURPOSE: Whereas allergic disease has the high morbidity during preschool age, there have not been sufficient surveys among the children in that age group. Thus we evaluated the prevalence of allergic disease among pre-school age children and risk factors which could cause or aggravate the disease. METHODS: A questionnaire survey was conducted among 593 kindergarten children, from 5 different kindergartens in Seoul between May and June, 2004. The standard for prevalence was whether one had been treated for allergic disease in past 12 months. Parents or guardians were surveyed to answer for each risk factor. RESULTS: For a question, "Have you been treated for allergic disease during past 12 months?", asthma showed 3.9% prevalence. For allergic rhinitis and atopic dermatitis were 11.1% and 20.1% respectively. Children with at least one of three diseases were 29.7%. Among children with asthma, risk factors were past history of bronchiolitis and paternal history of allergic disease. For allergic rhinitis, they were past history of bronchiolitis, mother's high education, and maternal history of allergic disease. For atopic dermatitis, risk factors were history of allergic disease of mother and father only. Other possible risk factors were statistically insignificant. CONCLUSION: Compared to the prevalence of primary school children (1995, 2000), asthma showed no difference but allergic rhinitis was lower and atopic dermatitis was higher. Among pre-school children, risk for allergic disease was higher with parental history of allergic disease. Especially the risk for respiratory allergy was even higher for those children with history of bronchiolitis.

Small Bowel-Mesentery-Small Bowel Fistula Caused by Ingested Magnets / 대한소아소화기영양학회지

Accidental foreign body ingestion is one of the general pediatric problems. If more than one magnet are ingested, they can attract each other across the intestinal wall. This kind of event may cause necrosis, perforation or fistula. Therefore, they must be retrieved by gastroduodenoscopy while they are still in the stomach. The authors have experienced an unusual small bowel complication, which was small bowel-mesentery-small bowel fistula, caused by the ingestion of magnets.

A Clinical Study on Benign Convulsions with Mild Gastroenteritis / 소아과

PURPOSE: 'Benign convulsions with mild gastroenteritis(BCwMG)' is afebrile seizures associated with gastroenteritis without dehydration or electrolyte imbalance in young children aged almost 6 months to 3 years. Because seizures can occur repeatedly, patients can be misdiagnosed with epilepsy. Therefore, understanding the characteristics of this disease is thought to be important. This study was carried out to investigate the clinical features of the disease. METHODS: From January, 2000 to December, 2003, 17 patients with BCwMG visited the Emergency Department, Inje University Ilsan Paik Hospital. We reviewed the clinical features of seizures, age and sex distribution, laboratory findings and follow-up results. RESULTS: Out of 17 patients with BCwMG, 13 were boys and five girls. Of 17 patients, 14(82.4%) patients were between 1 and 2 years of age. Generalized seizure was observed in all 17 patients. The duration of seizure was between 10 seconds and 10 minutes. Mean seizure frequency was 1.9 times(range, 1-5 times). Two or more seizures occurred in 10 patients(58.8%). All patients had seizures after the onset of gastroenteritis. All episodes occurred within the first five days of gastroenteritis. Rotavirus antigen was positive in stools in eight out of 12 patients(66.7%). Thirteen patients displayed normal psychomotor development at the last follow-up. No patient exhibited a the recurrence of seizures, except for one patient who had a febrile convulsion. CONCLUSION: Our results exhibited that BCwMG is characterized by seizures that are mostly brief and generalized and a cluster of episodes in those aged 1 to 2 years. Seizures occurred within the first three days of gastroenteritis. The proportion of positive rotavirus antigen was more than half.

A Clinical Study on the Etiologies of Acute Seizures in Children Who Visited Emergency Department / 소아과

PURPOSE: Although it is important to know the etiologies of childhood seizures according to age, clinical studies on this topic have been few. The present study was therefore designed to investigate the causes of acute childhood seizures. We hope this study will be helpful in the diagnosis and management of children with seizures. METHODS: This study was retrospectively undertaken to evaluate the age and sex distribution, the clinical seizure types, the seizure causes, and especially the frequencies of age-related seizure causes of 922 cases under 18 years of age, who visited Emergency Departments due to seizures from December, 1999 to January, 2004. RESULTS: The male to female ratio was 1.5 : 1 and the age range was from 1 day to 16 years, 2 months. There were 683 cases(74.1%) with generalized seizures, 61(6.6%) with partial seizures, and 178(19.3%) with unknown clinical seizure types. The causes of seizures were listed as follows : febrile convulsions in 545 cases(59.1%); epilepsies in 229(24.8%); benign convulsions with mild gastroenteritis in 19(1.6%); acute central nervous system infections in 15(1.6%); and metabolic derangements in six(0.7%). Finally, the frequencies of age-related seizure causes were analyzed. Out of 751 cases between 6 months and 5 years of age, 532 cases(70.8%) were febrile convulsions, 122(16.2%) epilepsies, 19(2.5%) benign convulsions with mild gastroenteritis, and 11(1.5%) acute CNS infections. Out of 145 cases among those over 5 years of age, 104 cases(71.7%) were epilepsies, 10(6.9%) febrile convulsions, and three(2.1%) acute CNS infections. CONCLUSION: The above results reveal that the causes of acute childhood seizures in the different age groups are different, and also suggest that febrile convulsion is the most common seizure cause between 6 months and 5 years of age, and epilepsy in more than 5 years of age. We hope that further clinical and epidermiologic studies on this topic will be performed.

Food Allergy; Diagnosis and Treatment / 소아알레르기및호흡기학회지

Up to 5% of young children suffer from food allergy. Children with food allergy may present with a variety of symptoms that parents have attributed to constituents of the diet. The diagnosis and management of adverse food reactions is a challenge for physicians. Diagnostic approaches are composed of a detailed history, in vitro tests and in vivo tests. Improved diagnostic methods include more precise in vitro and in vivo tests for immunoglobulin E-mediated food allergies, in vitro assays for predicting development of oral tolerance, and novel non-invasive tests for cell-mediated food allergies such as patch testing, cytokine assays, and detection of eosinophil activation markers. The conventional diet therapy, pharmacotherapy and new immunomodulatory approaches to food allergy are also discussed. Rapidly evolving findings might provide hope for a cure of food allergy in the near future.

Prevalence of Soy Protein Hypersensitivity in Cow's Milk Protein-Sensitive Children in Korea

This study was aimed to evaluate the prevalence of soy protein hypersensitivity in cow's milk protein-sensitive children in Korea. A total of 1,363 patients with atopic dermatitis, urticaria, enterocolitis syndrome, bronchial asthma or allergic rhinitis were recruited. First, we estimated the prevalence of sensitization to soy in children sensitized to cow's milk. Specific IgE levels > 0.7 kU/L by CAP assay were considered positive. Next, the prevalence of soy allergy in cow's milk allergy (CMA) patients was investigated. Those children whose parents agreed to participate the open challenge test with soy had a convincing history of allergic reactions elicited by cow's milk and these symptoms were relieved by elimination. All of them had negative soy-specific IgE. Patients with positive soy-specific IgE accounted for 18.3% of 224 children sensitized to cow's milk protein. The prevalence of sensitization to soy decreased with age (36.8% in the first year of life, 16.4% in the second year, and 13.7% in the third year). Of 21 CMA patients, 42.9% (n=9) were determined to have soy allergy (mean age 10.3 months). Our results suggest that soy protein formula should be carefully used as a substitute for cow's milk in CMA patients, especially during infancy.

Nationwide Study for Epidemiological Change of Atopic Dermatitis in School Aged Children between 1995 and 2000 and Kindergarten Aged Children in 2003 in Korea / 소아알레르기및호흡기학회지

OBJECTIVE: Atopic dermatitis is a chronically relapsing inflammatory skin disease. However, little is known about the prevalence of atopic dermatitis outside of North America and Europe. We evaluated the nationwide prevalence of atopic dermatitis with the comparison of prevalence between 1995 and 2000, and between Seoul and provincial cities in Korea. We also evaluated the risk factors for atopic dermatitis. METHODS: A cross-sectional ISAAC based questionnaire survey was conducted on random samples of schoolchildren (6 to 15 year olds) in 1995 and 2000. And kindergarten children (5 year olds) were surveyed in 2003, throughout South Korea. RESULTS: The lifetime and last twelve months prevalence of atopic dermatitis in Korean school-aged children was increased from 1995 to 2000. The twelve-month prevalence of atopic dermatitis was higher in Seoul than in other provincial cities in 1995, but the prevalence of atopic dermatitis in Seoul and Provincial Centers became similar in 2000. CONCLUSION: The prevalence of atopic dermatitis in Korean school-aged children was increased from 1995 to 2000. The further evaluations that include objective examination are necessary to confirm these outcomes because the environmental and risk factors may be different among the countries according to their life styles.

A Case of Unilateral Absence of Pulmonary Artery

Unilateral absence of pulmonary artery is a rare congenital anomaly that is frequently associated with other cardiovascular abnormalities. Most patients who have no associated cardiac anomalies have only minor or absent symptoms in childhood and survive into adulthood. We experienced a case of unilateral absence of pulmonary artery in a 5 year-old female patient with the chief complaint of abnormal chest X-ray finding. Unilateral absence of pulmonary artery was diagnosed by lung perfusion scan, cardiac catheterization with pulmonary and aortic angiography. So we report this case with brief review of related literatures.

A case of hypereosinophilic syndrome with pleural effusion and pulmonary embolism / 천식및알레르기

Hypereosinophilic syndrome is characterized by prolonged eosinophilia of blood and bone marrow and eosinophil-related tissue damage to variable organs without an identifiable underlying cause. We report a case of hypereosinophilic syndrome with pleural effusion and pulmonary embolism in a 29-year-old man. Chest CT and lung perfusion scan demonstrated multiple segmental perfusion defects in both lungs. After intravenous injection of methyl-prednisone for 3 weeks, blood eosinophil count and pulmonary lesions were normalized.

Cerebral Salt Wasting Syndrome Associated with Meningitis in a Child

Hyponatremia is commonly seen in those patients with central nervous system injury associated with infection or trauma. And decreasing intracranial pressure through restriction of maintenance fluid and salt is practiced as a routine therapeutic measure in the early stages of meningitis to prevent or ameliorate the syndrome of inappropriate secretion of antidiuretic hormone(SIADH). However, lots of patient do not show the typical symptoms of SIADH, instead they are dehydrated, have low plasma volume, increased urine sodium concentration and increased net sodium loss, which are the symptoms of cerebral salt wasting syndrome(CSW). Recent reports have prompted a reconsideration of CSW distinct from SIADH and moreover CSW has more proportion of hyponatremia associated with acute brain insult. CSW involves renal salt loss leading to hyponatremia and volume loss, whereas SIADH is a euvolemic or hypervolemic condition. While fluid restriction is the treatment of choice in SIADH, the treatment of CSW consists of vigorous sodium and volume replacement. And by correcting hyponatremic state as soon as possible, we can reduce mortality rate and improve neurologic sequelae. We report a case of CSW which was treated by replacement of vigorous sodium and volume replacement.

The sensitization rates to egg, milk, soy bean in children with atopic dermatitis and acute urticaria / 천식및알레르기

BACKGROUND: Atopic dermatitis(AD) and urticaria(UR) are common allergic diseases associated with various food allergens. We evaluated possible differences of sensitization rates to egg, milk, and soy bean according to the age in children with AD and UR. MATERIALS AND METHOD: One hundred and thirty-six patients(n=100 in AD, n=36 in UR) who had visited Samsung Medical Center from January 1998 to February 2000 were enrolled and divided into 3 groups by age: gruop I, children under 1year of age (45 in AD, 17 in UR); group II, between 1 and 3 years of age (32 in AD, 12 in UR); and group III, children over 3 years of age (23 in AD, 7 in UR). Total and specific IgE to cow milk, a-lactalbumin(a-LA), beta-lactoglobulin(beta-LG), casein, soy, egg white(EW) and egg yolk(EY) were measured by RAST or CAP system. RESULTS: Total IgE was highest in group III of AD patients(p0.05). The most common allergen among AD patients was EW(54%) for all age groups (51.1% in group I, 56.3% in group II, 56.5% in group III), while among UR patients, beta-LG(22.2%) was the most common food allergen, especially beta-LG(35.3%) in Group I, CM/casein(27.3%) in Group II, and CM/alpha-LA/casein/EW(12.5%) in Group III. Sensitization rate to EW, EY and soy bean were higher in AD than in UR(p<0.05). CONCLUSION: Sensitization rate to egg was higher in patients with AD than in those with UR. Restriction of eggs maybe helpful in management of infants with a family history of AD.

Airway obstruction by congenital cardiovascular anomaly / 소아알레르기및호흡기학회지

PURPOSE: This study was performed to review the clinical presentation, diagnostic methods, treatments and prognosis of children with vascular rings. METHOD: We reviewed the medical records of 7 patients with vascular ring who were admitted in Samsung medical center between 1996 and 2000 retrospectively. RESULT: Pulmonary artery sling was noted in 4 cases. Two cases had double aortic arch, and 1 case had right aortic arch with left ligamentum arteriosus and aberrant left subclavian artery. The mean age at onset of symptoms was 3.2 months(from birth to 11 months). The mean age at diagnosis was 7.0 months(from 6 weeks to 15 months). Presenting symptoms and signs were respiratory difficulty, stridor, chest retraction, coughing, grunting, wheezing, sputum, cyanosis, choking, dysphagia, and poor feeding. All patients with pulmonary artery sling had tacheobronchial and/or pulmonary anomalies and cardiac defects were associated in two of them. Surgical repair was done successfully for the patients with double aortic arch or right aortic arch, but three deaths occurred to the patients with pulmonary artery sling combined with bronchial anomaly. CONCLUSION: Vascular ring should be considered especially for infants with respiratory distress or chronic respiratory symptoms. Associated anomalies are likely to affect the prognosis in these patients.

Measles, Mumps, and Rubella Immunization in Children with Egg Allergies

PURPOSE: The safety of MMR(Measles, Mumps, and Rubella) immunization to children with egg allergies has been debated for decades because the live attenuated virus used in the vaccine is grown in cultured chick-embryo fibroblasts. Many studies that investigated adverse reactions to MMR vaccine have been reported abroad, but there has been no report in Korean children. So, this study is aimed at determining the prevalence of positive reactions to skin test with the diluted MMR vaccine and the safety of MMR immunization in Korean children with egg allergies. METHODS: Twenty children who have atopic dermatitis or urticaria associated with egg allergies in Samsung Medical Center underwent prick and intradermal tests with diluted MMR vaccine. Then, we administered the vaccine to the children subcutaneously. RESULTS: One patient(5.0%) had a positive result on the prick test and five(25.0%) on the intradermal test. Urticaria was elicited after MMR immunization in two children(10%) who had past illness of urticaria. One of them had a positive result on the prick and intradermal tests, but the other had negative results on both tests. CONCLUSION: Although anaphylaxis did not appear in our study, adverse reactions to MMR vaccination can occur in children with egg allergies, regardless of skin test result to MMR vaccine, prick or intradermal. Thus, in children with a history of severe systemic allergic reaction to egg, it is safe to perform MMR vaccination in a tertiary medical center where emergency care can be taken appropriately.

Role of Flexible Fiberoptic Bronchoscopy in the Diagnosis of Childhood Endobronchial Tuberculosis / 소아알레르기및호흡기학회지

Endobrochial tuberculosis which may result in stenosis of the bronchus, is a rare complication of pulmonary tuberculosis in children. We recently treated three children with endobronchial tuberculosis which presented different clinical manifestations and different response to the treatments. Endoscopic examinations revealed bronchial masses, in which biopsy and polymerase chain reaction(PCR) were consistent with endobronchial tuberculosis. We reviewed the presentation and treatment of endobronchial tuberculosis in 3 children.

Congenital Cystic Adenomatoid Malformation of the Lung: Analysis of 17 Cases / 소아알레르기및호흡기학회지

PURPOSE: Congenital cystic adenomatoid malformation of the lung(CCAM) is characterized by an excessive overgrowth of terminal bronchiolar-type structures with a lack of mature alveoli. This study was performed to evaluate the manifestation among different pathologic classification. METHODS: Seventeen patients admitted to the Samsung Medical Center from January 1995 to June 2000, were investigated for their clinical characteristics, radiologic findings, timing of treatment and post-operative outcome in each type. RESULTS: 1) Seven patients have type 1, while 9 cases were type 2. One case was diagnosed as having mixed type. Mean ages at diagnosis are 7 years 4 months. 2) 4 cases had experienced respiratory diseases that are pneumonia(3 cases), empyema(2 cases) and lung abscess(2 cases). 3) The most common clinical manifestations are fever and cough, followed by chest pain, dyspnea, cyanosis, weak crying and moaning. 4) The left lung(10 cases), especially left lower lobe(8 cases) is involved more frequently than right lung. 5) Associated anomalies are pulmonary sequestration, pectus excavatum, diaphragmatic hernia. 6) All lesions were surgically removed and all of patients survived. In our cases, there was no difference in outcome by age at operation. CONCLUSION: In this study, CCAM show various clinical manifestations, and the outcome is good irrespective of their pathologic type and age at operation. Probably this is due to few associated anomalies in our cases, but it is not clear whether this is common finding in Korea. Our findings suggest that CCAM is treated successfully by surgical removal which can be delayed unless respiratory symptoms are evident.

A Clinical Study of Adenoviral Respiratory Infection in Children

PURPOSE: Adenoviral respiratory infection can develop a life threatening condition similar to severe bacterial pneumonia. Despite adequate intensive care, this infection progresses to acute respiratory distress syndrome and causes permanent lung damage in some patients. In this study, we analyzed clinical features and long-term follow-up clinical data of this infection in children. METHODS: Forty-seven cases of inpatients were diagnosed as adenoviral respiratory tract infection by viral culture of nasal aspirates or histopathological diagnosis at Samsung Medical Center during the period from February 1995 to July 1998. We reviewed medical records retrospectively. RESULTS: During this study, 1301 cases of acute respiratory tract infection were investigated, of which 47 cases were confirmed as adenoviral infection. Age ranged from 2 months to 6 years. Initial symptoms were productive cough(100%), fever(91%), dyspnea(62%), diarrhea(40%), and conjunctival injection(30%). Thirty-nine cases(83%) were pneumonia and 7 cases(15%) were bronchiolitis. The radiologic findings were pneumonic consolidation(60%), effusion(36%), infiltration(19 %), and atelectasis(13%). Five cases developed acute respiratory distress syndrome and 3 cases expired. In 31 cases of recovered patient, follow-up evaluation was done at a minimum of 3 months(mean duration 9.9+/-9.3 months). Under the follow-up evaluation, 13 patients(42%) showed physical and radiologic findings that consisted with bronchiolitis obliterans or bronchiectasis. CONCLUSION: Because of severe clinical manifestations and pulmonary complications, early diagnosis, adequate management, and long-term follow-up are needed for adenoviral respiratory tract infection.