Biomedical subjects

J R Groothuis

Publications and source records attributed to J R Groothuis.

At least 37 records · Page 2Linked to original sources

PubMed1994

The role of RSV neutralizing antibodies in the treatment and prevention of respiratory syncytial virus infection in high-risk children.

Studies assessing the use of RSV immune globulin in the treatment of RSV illness are not yet completed. However, a large multicenter trial demonstrated that prophylaxis with RSV immune globulin was safe and efficacious in prevention of serious RSV disease in high-risk infants. Refinements in the practical application of RSVIG are needed, as intravenous lines are difficult to place and maintain in these fragile infants. With the development of concentrated polyclonal and/or effective monoclonal antibody preparations, it may be possible to immunize intramuscularly (Tempest et al., 1993; Barbas et al., 1992). The efficacy of RSV-specific monoclonal antibodies must still be defined, and the appropriate viral epitopes targeted. While these issues still need to be addressed, it is exciting to have finally produced a safe and effective way to prevent severe RSV disease in high-risk young children.

Animals↗

PubMed1994

Safety and immunogenicity of a purified haemagglutinin antigen in very young high-risk children.

Forty-three high-risk preterm children received either one of three doses of purified hemagglutinin antigen (HA) (7.5 micrograms/0.25 ml, 22.5 micrograms/0.25 ml or 67.5 micrograms/0.25 ml) or standard split product vaccine (ST) (22.5 micrograms/ml dose) over the 1990-1991 influenza season. Components for all vaccines included A/Shanghai 16/89, A/Taiwan 1/86 and B/Yamagata 16.88. Sera for antibody was drawn before, 6 weeks and 4 months after the first vaccine dose. The study was randomized and blinded. All children received two 0.25 ml doses of vaccine 4 weeks apart. No significant local or systemic reactions occurred. Six weeks after the first dose, children receiving ST vaccine had significantly higher seroconversion rates to A/Shanghai (p = 0.03) and to A/Taiwan (p = 0.01) than did those receiving equivalent HA vaccine. However, seroconversion rates were significantly higher for those children receiving the highest HA dose. All four vaccine groups responded poorly to B/Yamagata. Geometric mean titres were low for all groups and declined over 4 months. These results suggest that the equivalent dose of HA vaccine offers no advantage over ST vaccine in the immunization of high-risk preterm children.

Antibodies, Viral↗

PubMed1994

Efficacy and safety of aerosolized ribavirin in young children hospitalized with influenza: a double-blind, multicenter, placebo-controlled trial.

We randomly assigned children hospitalized with influenza who had been ill < or = 48 hours and who had a temperature > or = 37.8 degrees C to receive either ribavirin or placebo. All patients had evaluations performed for fever reduction, use of acetaminophen for temperature > or = 38.3 degrees C, duration and severity of influenza symptoms, and feeding behavior. Sixty-two patients (35 in the placebo group, 27 in the ribavirin group) had a diagnosis of influenza confirmed by laboratory study. The groups did not differ significantly in age, initial signs and symptoms, or in distribution of influenza A or B infections. The time to reduction of temperature < or = 38.3 degrees C for the ribavirin group was 8.9 hours compared with 22.6 hours for the placebo group (p = 0.04). The mean duration of acetaminophen use was 7.4 hours in the ribavirin group and 16.3 hours in the placebo group (p = 0.14). There were no significant differences between the groups in outcome of respiratory rate, pulse rate, cough, or level of consciousness. Convalescent influenza antibody geometric mean titer for the placebo group was 9.8 compared with 3.6 for the ribavirin group (p = 0.04). Ribavirin was more effective than placebo in accelerating normalization of temperature but there were no other significant differences.

Acetaminophen↗

PubMed1994

Role of antibody and use of respiratory syncytial virus (RSV) immune globulin to prevent severe RSV disease in high-risk children.

Infants with cardiac disease or infants born prematurely with or without bronchopulmonary dysplasia are at increased risk of severe respiratory syncytial virus (RSV) disease. A recently developed RSV immune globulin (RSVIG) was studied in a 3-year multicenter trial to determine safety and efficacy in the prevention of severe RSV disease in children who are at high risk of severe RSV illness. Two hundred forty-nine children were studied; 102 had bronchopulmonary dysplasia, 87 had congenital heart disease, and 60 were born prematurely. RSVIG was given on a monthly basis to 81 children at a high dose of 750 mg/kg (15 ml/kg) and to 79 children at a low dose of 150 mg/kg (3 ml/kg). The 89 children in the control group did not receive RSVIG. There were 64 episodes of RSV infection: 19 in the high-dose group, 16 in the low-dose group, and 29 in the control group. High-dose recipients had significantly fewer RSV lower respiratory tract infections, hospitalizations, hospital days, intensive care unit days, and less use of ribavirin compared with control subjects. Only 19 adverse events were reported during the 580 infusions administered (3%). No death was attributed to RSV disease or RSVIG therapy. Treated children did not acquire exaggerated RSV illness in a subsequent year. Thus high-dose RSVIG reduced the incidence and severity of RSV lower respiratory tract infection. It is a safe and effective means of RSV prophylaxis in selected high-risk children.

Animals↗

PubMed1994

Role of antibody and the use of respiratory syncytial virus immunoglobulin in the prevention of respiratory syncytial virus disease in preterm infants with and without bronchopulmonary dysplasia.

Respiratory syncytial virus (RSV) is the only viral respiratory pathogen that produces an annual epidemic of respiratory illness. Infants with cardiac disease or infants born prematurely with or without bronchopulmonary dysplasia are at increased risk of severe RSV disease. A recently developed RSV immunoglobulin (RSVIG) was studied to determine safety and efficacy in prevention of severe RSV disease in such children who are high risk for severe RSV illness. Results from this prospective, blinded trial involving 249 children (102 with broncho-pulmonary dysplasia, 87 with congenital heart disease and 60 who were born prematurely) indicate that high dose RSVIG reduced the incidence and severity of RSV lower respiratory tract infection. It is a safe and effective means of RSV prophylaxis in selected high risk children.

Antibodies, Viral↗

PubMed1993

Prophylactic administration of respiratory syncytial virus immune globulin to high-risk infants and young children. The Respiratory Syncytial Virus Immune Globulin Study Group.

BACKGROUND: Infants with cardiac disease or prematurity are at risk for severe illness caused by respiratory syncytial virus. Immune globulin with a high titer of antibodies against respiratory syncytial virus may offer infants and young children at risk protection from this serious, common respiratory illness. METHODS: We studied 249 infants and young children (mean age, eight months) who had bronchopulmonary dysplasia due to prematurity (n = 102), congenital heart disease (n = 87), or prematurity alone (n = 60). Respiratory syncytial virus immune globulin was given monthly to some of these children in either a high dose (750 mg per kilogram of body weight; n = 81) or low dose (150 mg per kilogram; n = 79); 89 controls received no immune globulin. Group assignments were random. Assessments of respiratory illness and management were conducted without knowledge of the children's group assignments. RESULTS: There were 64 episodes of respiratory syncytial virus infection: 19 in the high-dose group, 16 in the low-dose group, and 29 in the control group. In the high-dose group there were fewer lower respiratory tract infections (7, vs. 20 in the control group; P = 0.01), fewer hospitalizations (6, vs. 18 in the control group; P = 0.02), fewer hospital days (43, vs. 128 in the control group; P = 0.02), fewer days in the intensive care unit (P = 0.05), and less use of ribavirin (P = 0.05). In the low-dose group there was a significant reduction only in the number of days in the intensive care unit (P = 0.03). Adverse events during the 580 infusions were generally mild and included fluid overload (in five children), oxygen desaturation (eight), and fever (six). Six children died: three in the high-dose group, three in the low-dose group, and none in the control group (P = 0.15), but no death was attributed to the use of immune globulin or to illness caused by respiratory syncytial virus. CONCLUSIONS: Administration of high doses of respiratory syncytial virus immune globulin is a safe and effective means of preventing lower respiratory tract infection in infants and young children at high risk for this disease.

Antibodies, Viral↗

PubMed1993

Preterm twins and triplets. A high-risk group for severe respiratory syncytial virus infection.

OBJECTIVE: To assess the impact of multiple births and crowded homes on the severity of respiratory syncytial virus illness in preterm infants with bronchopulmonary dysplasia. RESEARCH DESIGN: Retrospective case-control chart review from a prospective longitudinal respiratory illness study. SETTING: Neonatal High-Risk Follow-Up Clinic (outpatient setting) and tertiary care hospitals (inpatient setting). PARTICIPANTS: Fourteen sets of twins and two sets of triplets followed up between 1983 and 1989 and matched with 34 singleton infants for date of birth (within 3 months) and gestational age (within 1 month). MEASUREMENTS/MAIN RESULTS: The risk of developing respiratory syncytial virus illness was significantly higher in multiple-birth infants than in singletons (53% vs 24%; P = .01). Multiple-birth infants were also at greater risk for developing pneumonia (24% vs 6%; P = .05) and requiring hospitalization (32% vs 18%; P = .05) than were singletons. Additional risk factors for developing pneumonia and bronchiolitis were examined in all 68 children. Multiple birth (P = .05), gestational age of less than 30 weeks (P = .02), and crowded homes (defined as more than one person living in 19 m2 of living space [P = .002] or more than one child living in 22 m2 of living space [P = .004]) were additional risk factors for developing pneumonia. CONCLUSION: Multiple-birth preterm infants are at a higher risk of developing pneumonia than are singletons. Additional risk factors for developing pneumonia in preterm infants with bronchopulmonary dysplasia include gestational age of less than 30 weeks and crowded homes. At-risk infants with any of these risk factors should be targeted for prophylactic and therapeutic interventions against respiratory syncytial virus.

Birth Weight↗

PubMed1993

Controlled trial to evaluate protection of high-risk infants against respiratory syncytial virus disease by using standard intravenous immune globulin.

We performed a randomized, controlled trial of intravenous immune globulin (respiratory syncytial virus [RSV] neutralizing [Nt] antibody titer of 1:950 in 5% solution) to evaluate protection against RSV-induced disease over two respiratory virus seasons. Forty-nine children (mean age at enrollment, 4.5 months) with severe congenital heart disease or bronchopulmonary dysplasia were randomized as follows. Twenty-four patients were followed as controls and received no immune globulin. Twenty-five patients received monthly infusions of immune globulin at a dose of 500 mg/kg of body weight. There was a similar distribution between groups of patients with heart disease and bronchopulmonary dysplasia. There were 12 culture-proven RSV infections, 6 in the prophylaxis group and 6 in the control group. There was a trend toward less severe RSV illness in immune globulin recipients, as measured by length of hospitalization. Four of the six immune globulin recipients were hospitalized for a total of 35 days (mean, 8.8 +/- 5.0 days) because of RSV illness, in contrast to 51 hospital days (mean, 12.8 +/- 7.6 days) among RSV-infected controls. We conclude that monthly infusions of standard immune globulin containing RSV Nt antibodies may be safely administered to high-risk children, but that standard intravenous immune globulin does not contain sufficient RSV Nt antibody titer to fully protect against severe RSV illness.

Humans↗

PubMed1992

Immune response to split-product influenza vaccine in preterm and full-term young children.

Humoral and cellular immune responses to two doses of influenza antigens were measured in children 6-48 months of age. These vaccinees comprised a previously unimmunized cohort of 18 healthy full-term children and 15 sick preterm children with bronchopulmonary dysplasia and an additional 30 ex-preterm children who were reimmunized. Half of the reimmunized cohort were recovered from bronchopulmonary dysplasia and half had active bronchopulmonary dysplasia. Antibody response was measured by haemagglutination inhibition (HI) and ELISA, and cellular immunity was measured by enumerating memory T cells. Six weeks after immunization, ELISA antibody levels were significantly higher in previously unimmunized full-term vaccinees than in previously unimmunized sick preterm infants (p less than 0.002). No difference was found between sick and recovered reimmunized children. By HI testing greater than 90% of children in both cohorts developed titres greater than or equal to 1:32, and these were generally maintained for at least 20 weeks. T-cell proliferative responses to influenza antigen were greater in the full-term children than in the preterm children (p less than 0.02), irrespective of state of health or prior immunization status. Split-product vaccine was immunogenic in all the cohorts studied; however, factors such as prematurity, health status and previous influenza immunization played important roles in the magnitude of some responses.

Antibodies, Viral↗

PubMed1991

Use of intravenous gamma globulin to passively immunize high-risk children against respiratory syncytial virus: safety and pharmacokinetics. The RSVIG Study Group.

Infants with cardiopulmonary disease develop severe illness from respiratory syncytial virus (RSV) infection. Safety, feasibility, and pharmacokinetics of intravenous gamma globulin (IVIG) to prevent RSV illness were studied in 23 high-risk infants in a phase I trial. IVIG with an RSV neutralizing antibody titer of 1:1,100 in 5% solution was given monthly over a 2- to 4-h period in a clinical setting during the RSV season. The first group (n = 7) received 500 mg/kg of body weight, the second group (n = 9) received 600 mg/kg, and the third group (n =7) received 750 mg/kg. Serum was drawn prior to infusion and 2, 14, and 30 days after infusion. Total immunoglobulin G and RSV A2 and RSV B neutralizing antibody levels were obtained after the first IVIG infusion. Two children developed mild reversible pulmonary edema (group receiving 600 mg/kg per dose), and one developed hives and wheezing during one infusion (group receiving 500 mg/kg per dose). Twelve children developed subsequent RSV infection during two RSV seasons (November to April) over a 2-year follow-up period; 9 of 12 developed infection during the infusion year. Eleven illnesses were mild; one child died of progressive RSV illness (group receiving 500 mg/kg per dose). A cumulative infusion effect was not observed. IVIG appears safe and feasible in an outpatient setting, and at 750 mg/kg per dose, a target RSV antibody level of greater than or equal to 1:100 was achieved.

Child, Preschool↗

PubMed1991

Antibody responses to influenza B viruses in immunologically unprimed children.

The cocirculation in several parts of the world of influenza viruses B/Yamagata/16/88 and B/Victoria/2/87, which are genetically and antigenically divergent, has prompted the question of whether immunization with one viral antigen is sufficient for protection against both strains. Twenty-three high-risk infants and young children were immunized with a commercial trivalent influenza vaccine containing the antigens of influenza virus B/Yamagata/16/88. When antibodies against influenza viruses B/Yamagata/16/88 and B/Victoria/2/87 were determined, increases developed uniformly to both in the sera of primed children previously exposed to influenza virus B/Victoria/2/87 by immunization or infection. Antibodies against B/Yamagata/16/88 developed in the sera of unprimed children with titers similar to those of the primed children. However, antibodies to B/Victoria/2/87 were not detected in the sera of the unprimed children. These data suggest that children without appropriate immunologic priming may not be protected against an infection with a B/Victoria/2/87 strain after vaccination with a B/Yamagata/16/88 strain. Immunization with more than one influenza B virus strain may be desirable in some high-risk pediatric patients if divergent influenza B viruses circulate.

Antibodies, Viral↗

PubMed1991

Immunization of high-risk infants younger than 18 months of age with split-product influenza vaccine.

Influenza is an important cause of serious illness in very young children with cardiopulmonary disease. A 4-year study was conducted at two centers to assess immunogenicity and safety of influenza split-product vaccine in children aged 3 to 18 months with bronchopulmonary dysplasia and congenital heart disease. A total of 113 children were studied: 62 children 3 to 5 months of age and 51 children 6 to 18 months of age. Sera were drawn prior to first and second immunization and 3 weeks after second immunization and were tested by hemagglutination inhibition; protection was defined as greater than 1:32. Ninety-five children were surveyed for adverse reactions. Seroresponses were age and antigen specific. Best responses for all ages were to A/Mississippi (H3N2) (97%). Children older than 6 months of age had better seroresponses to A/Leningrad (H3N2) (73%, P less than .03) and B/Victoria (62%, P less than .02) than did children younger than 6 months of age. Seroconversion rates to the remaining antigens were low. Only 9% of children experienced adverse reactions; all but one were mild. The immunologic mechanisms responsible for preventing serious influenzal disease and more effective immunization strategies need to be defined for very young high-risk children.

Aging↗

PubMed1990

Severe respiratory syncytial virus infection in older children.

Serious respiratory syncytial virus (RSV) disease requiring hospitalization occurs primarily in infants younger than 12 months. The incidence, risk factors, and clinical features in older children have not been studied extensively. Of 282 children hospitalized at our institution with severe RSV disease during a 3-year period, 62 (22%) were older than 12 months. These 62 older children were matched for sex, onset of illness, and hospital location with 62 hospitalized children younger than 12 months with proved RSV infection. Older children had underlying chronic disease more commonly than younger children (47 of 62 vs 24 of 62). Chronic illnesses in older children included bronchopulmonary dysplasia and/or reactive airway disease (34 of 47), congenital heart disease (9 of 47), gastrointestinal disease (7 of 47), and genetic disorders (7 of 47). Three of the four deaths from RSV infection occurred in older children; all four had underlying disease (three with congenital heart disease and one with biliary atresia). We conclude that children older than 12 months with underlying disease are at increased risk for serious or fatal RSV infection and are not always protected by previous RSV disease. Such older children should be considered candidates for passive or active immunoprophylaxis against RSV infection as such agents become available.

Age Factors↗

PubMed1990

Early ribavirin treatment of respiratory syncytial viral infection in high-risk children.

A 3-year prospective, blinded, multicenter study was done to assess the efficacy of early ribavirin intervention in mild respiratory syncytial virus illness in children with bronchopulmonary dysplasia or with congenital heart disease. A cohort of 178 children younger than 36 months of age with bronchopulmonary dysplasia or congenital heart disease were followed. Forty-seven infants whose respiratory syncytial virus infection resulted in mild symptoms of less than or equal to 72 hours' duration received ribavirin (n = 20) or water placebo aerosol (n = 27) either in a hospital or at home. Outcome measures included respiratory and analog score, room air oxygen, saturation, and oxygen flow needed to maintain saturation at greater than or equal to 91%. No difference in age, gender, family size, passive smoking, baseline oxygen saturations in room air, or duration of symptoms before treatment was found between groups. After 3 days of therapy, ribavirin produced a greater rate of improvement of analog scores (p = less than or equal to 0.001), lower oxygen requirements (p = 0.01), and higher oxygen saturation (p = 0.01). Respiratory scores and total hospital days did not differ significantly between the groups. Treatment failure occurred in 2 of 20 children (10%) in the ribavirin group versus 5 of 27 children (18%) in the placebo group, a nonsignificant difference. No child required assisted ventilation or had an adverse reaction. We conclude that early ribavirin therapy may help to reduce morbidity from respiratory syncytial virus infection in high-risk young children.

Bronchopulmonary Dysplasia↗

PubMed1988

Galactose, glucose, and lactate concentrations in the portal venous and arterial circulations of newborn lambs after nursing.

We have used the newborn lamb prepared with chronic indwelling catheters to study carbohydrate metabolism in the unstressed, postprandial state. Lambs were fasted 5 h and then allowed to nurse ad libitum from their mothers for 20 min. Serial determinations of whole blood galactose, glucose, and lactate concentration were then made from the portal venous and arterial circulations. Portal venous galactose concentration increased significantly after milk ingestion, but arterial galactose concentration did not increase from baseline unless the portal venous galactose concentration exceeded 10-12 mg/dl suggesting a threshold effect for hepatic galactose clearance. Glucose concentration increased significantly in both circulations with portal venous galactose concentration greater than arterial galactose concentration in all cases. Galactose and glucose were absorbed from the intestine at approximately equal rates. Lactate was not absorbed into the portal venous circulation to any great extent after lactose ingestion.

Animals↗

PubMed1988

Respiratory syncytial virus infection in children with bronchopulmonary dysplasia.

Little is known about the risk of severe illness from respiratory syncytial virus infection in children with bronchopulmonary dysplasia. A prospective study was done of the natural history of respiratory syncytial virus infection in 30 children less than 2 years of age with bronchopulmonary dysplasia who were in a home oxygen program. Surveillance to identify children with acute respiratory symptoms was done by weekly telephone interview. Symptomatic children were examined, oxygen saturation was determined by oximetry, and nasopharyngeal lavage fluid was collected for virus cultures and rapid respiratory syncytial virus antigen tests. During the 4-month study period (December to April), 27 children had one or more acute respiratory illnesses, and respiratory syncytial virus developed in 16/27 (59%). Passive smoking and greater than or equal to four members in the home increased the risk of symptomatic respiratory syncytial virus (P less than .01 and P less than .03, respectively). Of 16 children, 11 (69%) required hospitalization. Of the 11 hospitalized children with respiratory syncytial virus, nine were either still receiving oxygen at home or required oxygen therapy within the previous 3 months v none of five nonhospitalized children (P less than .005). Five of the hospitalized children were greater than 12 months of age and five had respiratory syncytial virus infection previously that had been confirmed by culture results. Hospitalizations were prolonged and complicated. Seven of 11 children were hospitalized for greater than 1 week; four were admitted to the intensive care unit; four were treated with ribavirin aerosol, and two needed mechanical ventilation. There were no deaths.(ABSTRACT TRUNCATED AT 250 WORDS)

Bronchopulmonary Dysplasia↗

PubMed1987

Home oxygen promotes weight gain in infants with bronchopulmonary dysplasia.

To study the effect of oxygen therapy on weight gain in bronchopulmonary dysplasia (BPD), the growth of 22 infants with BPD enrolled in a premature follow-up clinic and home oxygen program was examined retrospectively. Mean gestational age was 28 weeks (range, 26 to 33 weeks) and mean birth weight was 1110 g (range, 680 to 2000 g). After discharge, infants were monitored monthly to maintain transcutaneous oxygen tension over 55 mm Hg and/or pulse oximeter oxygen saturation over 92%. With appropriate home oxygen, all 22 infants grew as well as healthy, full-term infants (mean, 40th percentile; range, tenth to 80th percentile) when ages were corrected for prematurity. Parents discontinued oxygen therapy inappropriately in seven infants, and all seven experienced significant deceleration in weight gain. When home oxygen therapy was resumed, their weight gain improved, but the infants never regained their original percentiles during the study period. The 15 infants who continued home oxygen therapy maintained their original weight percentiles throughout the study period. These data support an important role for home nasal cannula oxygen in promoting weight gain in selected infants with BPD.

Body Weight↗

PubMed1987

Comparison of nasopharyngeal washings and swab specimens for diagnosis of respiratory syncytial virus by EIA, FAT, and cell culture.

Respiratory secretions for viral diagnosis are often collected with nasopharyngeal (NP) swabs, although many laboratories recommend NP aspirates or washings. We compared results using NP washings and NP swabs in three diagnostic RSV tests, a rapid RSV EIA antigen test (Abbott Laboratories), an indirect fluorescent antibody test (FAT) with rabbit antiserum, and virus culture (HEp-2 cells). Paired samples were collected from 121 children with suspected RSV bronchiolitis or pneumonia. A minitip swap was passed into the nasopharynx for 10 sec, rotated and withdrawn. The opposite nares was irrigated with approximately 1 ml of saline and aspirated using a syringe and plastic feeding tube. Fifty-one children (42%) grew RSV in culture, 49 from NP washings versus 27 from NP swabs (p less than 0.001). Fifty-three (44%) were positive by FAT, 52 from NP washings versus 12 from NP swabs (p less than 0.001). Fifty-eight children (48%) had positive RSV EIA tests, 57 from NP washings versus 35 from NP swabs (p less than 0.001). Detection by EIA was more sensitive than culture regardless of the method of specimen collection. We conclude that NP washings are superior to NP swabs for RSV culture and rapid diagnosis by EIA or FAT.

Child↗