Gastrointestinal dysfunction and disaccharide intolerance in children infected with human immunodeficiency virus.

Because gastrointestinal dysfunction is a major problem in children with human immunodeficiency virus (HIV) infection, we utilized breath hydrogen measurements to determine the relationship between disaccharide malabsorption and gastrointestinal dysfunction in HIV-infected children. We found a strong association between lactose intolerance and persistent diarrheal disease in this population (p less than 0.007, Mann-Whitney U test). We also found evidence of sucrose malabsorption and persistent diarrheal disease in three of the children. Extensive microbiologic evaluations failed to reveal an etiologic agent related to the occurrence of gastrointestinal symptoms. Our findings indicate that disaccharide intolerance is a common occurrence in HIV-infected children with persistent diarrheal disease. Careful attention to dietary intake may be required to ameliorate clinical symptoms and to maintain adequate nutrition.

Neonatal rotavirus-associated necrotizing enterocolitis: case control study and prospective surveillance during an outbreak.

After the death of a premature infant from rotavirus-associated necrotizing enterocolitis, we instituted prospective surveillance for this disease in our neonatal intensive care unit. During the 4-month study period an additional six cases of necrotizing enterocolitis and eight cases of hemorrhagic gastroenteritis occurred. Rotavirus infection was documented in 11 of these 15 symptomatic infants, in comparison with only eight rotavirus infections in 147 asymptomatic or minimally symptomatic babies (P less than 0.0001). Stools from 110 nursery personnel tested during the outbreak did not contain rotavirus. However, 12 of 59 staff members had serum IgM antibody against rotavirus, suggesting recent infection. In a case-control study we compared babies with severe gastrointestinal illness with a control group randomly selected from asymptomatic babies in the nursery during the time of the outbreak. Univariate analysis found six categorical variables and nine continuous variables that were significantly associated with disease. Multivariate logistic regression analysis, however, found only birth weight (P less than 0.0001), rotavirus infection (P less than 0.0001), and age at time of first nonwater feeding (P less than 0.02) to be associated with gastrointestinal illness. This study provides further evidence for the role of infection in some cases of neonatal necrotizing enterocolitis and hemorrhagic gastroenteritis.

Age-related rate of seropositivity of antibody to Giardia lamblia in four diverse populations.

We used a solid-phase enzyme immunoassay to determine the age-specific rates of acquisition of antibody to Giardia lamblia in populations living in an inner city area of Baltimore, Md., on an Apache Indian reservation in Arizona, in a rural area of Panama, and in an urban area of Peru (Lima). Antibody to G. lamblia was found in a portion of the adults living in all of the study areas. Similar prevalence rates and quantitative levels of antibody were found in the adults living in Arizona (44%), Panama (48%), and Peru (46%). However, a significantly lower (P less than 0.05) percentage of the adults living in Baltimore (18%) displayed serological evidence of infection. Different patterns of age-associated acquisition of antibody were noted in the study populations. In the United States, children living in Baltimore had low levels of seropositivity throughout childhood, whereas children living on the Arizona Indian reservation showed a progressive acquisition of antibody early in childhood, with adult levels achieved by 8 years of age. In Latin America, children living in Panama attained adult levels of seropositivity between 9 and 20 years of age, whereas children in Peru displayed adult levels of seropositivity in the first 6 months of life. Our findings documented the widespread occurrence of G. lamblia infections in diverse populations. Children living in different areas and under different environmental conditions displayed widely differing rates of acquisition of antibody to G. lamblia, possibly resulting from different levels of sanitation, water contamination, and person-to-person contact. Our studies indicate that quantitative solid-phase immunoassays can be used to study the epidemiology of parasitic infections such as those caused by G. lamblia.

Enzootic bovine rotavirus is not a source of infection in Panamanian cattle ranchers and their families.

Vaccination of humans against rotavirus (RV) diarrhea may be accomplished by oral immunization with attenuated animal strains known to be antigenically very similar to human strains. To define better the degree of infectivity in nature of these animal strains for humans, we conducted surveillance for RV infection/diarrhea in 180 farm workers, their 161 family contacts, and the 566 animals (512 cattle, 35 pigs, and 19 sheep) on 14 farms in rural Panama. No correlation between the high infection rates in farm workers (72%) and their family contacts (78%) and in cattle (56%) could be demonstrated. Heads of families with four or more children with RV infection experienced a twofold greater rate of RV infection compared with heads of families of similar size without RV infection. Despite the close similarity between human and bovine RV, in Panama intrafamilial (particularly child-to-child or child-to-parent) rather than interspecies transmission appeared to be the most important route for the spread of this highly infectious virus.

Prevalence of serum and milk antibodies to Giardia lamblia in different populations of lactating women.

We used an enzyme-linked immunosorbent assay system to compare prevalence and levels of systemic and local antibody to Giardia lamblia in different populations. Serial blood and milk samples were collected simultaneously from lactating women in Texas and Mexico. IgG antibody to G. lamblia was present in 118 (77%) of 153 sera from 27 Mexican mothers but in only 51 (24%) of 214 sera obtained from 28 Texan mothers (P less than .001). Sera positive for IgG antibody to G. lamblia revealed antibody levels that were significantly higher in Mexico than in Texas (0.325 +/- 0.076 vs. 0.219 +/- 0.079 optical density units). Secretory IgA antibody to G. lamblia was found in 121 (79%) of 153 milk samples in the Mexican population, but in only 33 (15%) of 214 samples in the Texan population (P less than .001). The levels of secretory antibody to G. lamblia also were higher in the Mexican population. The study documents a widely different antibody response to G. lamblia in individuals living in different areas. As antibodies to G. lamblia can be acquired by infants transplacentally or through breast-feeding, this difference might be important in the relative protection against giardial infection.

Estudio etiológico de enfermedades en vias respiratorias de niños / Etiologic study of respiratory tract diseases in children

"De Diciembre de 1982 a Marzo de 1983 fueron estudiados 401 niños menores de 6 años en la ciudad de La Ceiba, Honduras: 226 niños con síntomas de vías respiratorias y un grupo control (asintomático) de 175 niños. Se determinó la incidencia y prevalencia de diferentes tipos de virus y bacterias en la población estudiada, mediante aislamiento de antígenos y/o detección de anticuerpos séricos. Se obtuvo una incidencia de un 6l,06

de los pacientes estudiados con enfermedad respiratoria de etiología viral, ocupando el primer lugar el Virus Sincitial Respiratorio (RSV) con un 27,13

y en segundo lugar el Parainfuenza Virus (Para Flu) con un 22,19

. Otros virus fueron identificados en menor porcentaje. Se obtuvo una prevalencia de un 91,27

de pacientes con enfermedad respiratoria de etiología viral en la población estudiada. Tambiém aquí el virus más frecuentemente diagnosticado fue el RSV (70,07

). No se encontró gran diferencia en la distribución viral según nivel socio-económico ni sexo. También se detectaron anticuerpos séricos para el Mycoplasma pneumoniae en un 5,48

de los pacientes estudiados, para el Haemophilus Influenzae tipo b (H. flu b) en un 0,99

, para Chlamydiae en un 3,99

y para el Streptococcus pneumoniae 93 (Sp 93) en 1,99

de los pacientes, mostrando relativamente una mayor incidencia entre el grupo de niños en edad pre-escolar (2 a 6 años) (AU)

Estudio etiológico de enfermedades en vias respiratorias de niños / Etiologic study of respiratory tract diseases in children

"De Diciembre de 1982 a Marzo de 1983 fueron estudiados 401 niños menores de 6 años en la ciudad de La Ceiba, Honduras: 226 niños con síntomas de vías respiratorias y un grupo control (asintomático) de 175 niños. Se determinó la incidencia y prevalencia de diferentes tipos de virus y bacterias en la población estudiada, mediante aislamiento de antígenos y/o detección de anticuerpos séricos. Se obtuvo una incidencia de un 6l,06% de los pacientes estudiados con enfermedad respiratoria de etiología viral, ocupando el primer lugar el Virus Sincitial Respiratorio (RSV) con un 27,13% y en segundo lugar el Parainfuenza Virus (Para Flu) con un 22,19%. Otros virus fueron identificados en menor porcentaje. Se obtuvo una prevalencia de un 91,27% de pacientes con enfermedad respiratoria de etiología viral en la población estudiada. Tambiém aquí el virus más frecuentemente diagnosticado fue el RSV (70,07%). No se encontró gran diferencia en la distribución viral según nivel socio-económico ni sexo. También se detectaron anticuerpos séricos para el Mycoplasma pneumoniae en un 5,48% de los pacientes estudiados, para el Haemophilus Influenzae tipo b (H. flu b) en un 0,99%, para Chlamydiae en un 3,99% y para el Streptococcus pneumoniae 93 (Sp 93) en 1,99% de los pacientes, mostrando relativamente una mayor incidencia entre el grupo de niños en edad pre-escolar (2 a 6 años)

An outbreak of rotavirus-associated neonatal necrotizing enterocolitis.

An outbreak of necrotizing enterocolitis and hemorrhagic gastroenteritis occurred in two nurseries during 25 days in August 1982. Eleven of the 40 patients in these nurseries during that time developed disease (attack rate 27.5%). In seven of the 10 patients with gastrointestinal disease, stool samples tested for human rotavirus were positive by ELISA, whereas in 20 unaffected infants, no stools tested demonstrated HRV (P = 0.0001). Eleven staff members had serologic evidence of recent HRV infection. Comparison of risk factors traditionally associated with the development of NEC between the affected and unaffected infants revealed no significant differences. Rotavirus infection was the only finding that was highly correlated with this epidemic.

The role of respiratory syncytial virus and other viral pathogens in acute otitis media.

We utilized recently developed enzyme immunoassay techniques to examine the role of selected viruses in the etiology of acute otitis media. Viral pathogens were found in middle ear fluids obtained from 13 (24%) of 53 children with acute otitis media; respiratory syncytial virus accounted for ten of the 13 viral agents identified. In addition, respiratory syncytial viral antigen was found in nasopharyngeal washings obtained from 15 of the 53 children. Seven of these children had RSV identified as the sole middle ear pathogen, whereas six children had otitis caused by Streptococcus pneumoniae as either the sole middle ear pathogen or in combination with RSV. Similarly, all three children with respiratory infections caused by influenza virus had ear infections caused by bacterial pathogens, either alone or in combination with influenza virus. These findings suggest that, in patients with viral respiratory infection, coexisting acute otitis media may be associated with the recovery of either viruses or bacteria from the middle ear exudates.

Gastroenteritis associated with enteric type adenovirus in hospitalized infants.

Enteric types of adenovirus have recently been identified as a causative agent of infantile gastroenteritis. We utilized enzyme immunoassay and tissue culture techniques to evaluate prospectively the role of ET Ad in diarrhea occurring in hospitalized infants. We found that ET Ad was associated with 14 of 27 cases of diarrhea occurring during a 12-week study period in the late autumn and early winter months; ET Ad was found in the stool of only one of 72 children without diarrhea (P less than 0.001). Although adenoviruses other than ET Ad were found in the stools of two of the 27 children with diarrhea, such viruses were also found in the stools of five of 72 children without diarrhea and thus could not be statistically correlated with acute gastroenteritis. Children infected with ET Ad had diarrhea for a mean of 8.0 days, compared to a mean duration of 4.2 days for the children with gastroenteritis not associated with ET Ad. Thirteen of the 14 children with ET Ad gastroenteritis had respiratory symptoms such as cough, rhinorrhea, or wheezing, six had roentgenographic evidence of pneumonia, and three children had bilateral conjunctivitis. This study documents that ET Ad can be an important cause of acute gastrointestinal disease in hospitalized infants and young children and that gastrointestinal infections with ET Ad can be associated with a high rate of respiratory disease.

Rapid diagnosis of infections caused by beta-lactamase-producing bacteria by means of an enzyme radioisotopic assay.

We developed a sensitive enzyme radioisotopic assay for the measurement of beta-lactamase, an enzyme produced by a number of pathogenic bacteria. This ERIA was 100-fold more sensitive than the commonly used iodometric or spectrophotometric assays for the measurement of beta-lactamase and, unlike these other assays, the ERIA was not significantly influenced by serum proteins or unlabeled penicillin. Clinical specimens consisting of blood, peritoneal, pleural, and cerebrospinal fluids from patients infected with beta-lactamase-producing organisms yielded positive ERIA tests; fluids from uninfected patients were negative. The ERIA takes approximately 90 minutes to perform, and offers great potential for the rapid diagnosis of serious bacterial infections caused by bacteria which produce beta-lactamase.

Indirect enzyme-linked immunosorbent assay for the quantitation of the type-specific antigen of Haemophilus influenzae b: a preliminary report.

Infections with Haemophilus influenzae type b are major causes of morbidity and mortality in young children. We developed an enzyme-linked immunosorbent assay for the diagnosis of Hib infections. The ELISA was more sensitive than both counterimmunoelectrophoresis and latex agglutination for the detection of Hib antigen in serum, urine, and cerebrospinal fluid. In addition, no false positive ELISA reactions were noted. The increased sensitivity of ELISA was especially valuable in the detection of Hib antigen following antibiotic therapy, in which case cultures are often sterile and CIE and LA can be negative. ELISA is thus a valuable tool for the early diagnosis of Hib infections.

Chronic rotavirus infection in immunodeficiency.

The characteristics of rotavirus infection in 23 children with a variety of primary immunodeficiency diseases were studied. Stools and sera were tested for rotavirus by means of the enzyme-linked immunosorbent assay and the enzyme-linked fluorescent assay, respectively. Four immunodeficient patients had diarrhea during the study period and all had rotavirus infection; rotavirus was not detected in the stools of the 19 asymptomatic immunodeficient patients. Forty-six control children with diarrhea were tested and 22 had rotavirus infection; rotavirus was not detected in 39 asymptomatic control children. One immunodeficient patient with X-linked agammaglobulinemia and one with severe combined immunodeficiency had chronic, symptomatic rotavirus infection with rotavirus excretion lasting more than six weeks. The other two immunodeficient patients and eight control children eliminated the rotavirus from their stools in periods ranging from two to 12 days. Rotavirus antigen was detected in the sera of three of the four immunodeficient patients; none of the 14 control infants tested had rotavirus antigen detected in their sera. This study indicates that rotavirus may produce a chronic infection in immunodeficient children.

S-IgA cholera toxin and rotavirus antibody in human colostrum.

S-IgA antibodies against cholera toxin and rotavirus were assayed in 43 colostral samples by means of an enzyme-linked immunosorbent assay (ELISA). All specimens contained specific S-IgA antibodies against both antigens. Significant antibody titres to the antigens were demonstrated in almost all colostral samples.

Diarrhea associated with rotavirus in rural Guatemala: a longitudinal study of 24 infants and young children.

A population of 24 infants and young children followed prospectively during the first 3 years of life was studied for the occurrence of rotavirus infection by using enzyme-linked immunosorbent assay to detect virus in stools. Infection with rotavirus was associated with 26 (14.2%) of 183 selected diarrheal episodes. Twenty of the 24 infants and young children had diarrhea associated with rotavirus on at least one occasion and six had two such episodes. Rotavirus infection was documented in over 50% of the dehydrating episodes studied, thus further indicating the importance of rotavirus in this population.