Clinical features of adenovirus enteritis: a review of 127 cases.

We retrospectively analyzed the clinical features of 127 hospitalized pediatric patients whose fecal samples were positive for adenovirus (Ad) by electron microscopy during an 18-month period. Serotyping results obtained by microneutralization tests and restriction endonuclease analysis were available for 105 of 127 cases. There were 69 males and 58 females and 94% of patients were less than 4 years of age. The average body temperature was 38 degrees C rectal (range, 36.2-40.8 degrees C) with an average duration of fever of 1.6 days. The average duration of clinical illness was 8.8 days (range, 1 to 32 days). Although Ad 40 and Ad 41 were isolated in the majority of cases (59 of 105 (56%], Ad 31 was associated with 18 of 105 cases (17%). Of the 18 cases associated with Ad 31, 14 were nosocomial and associated with diarrhea. Our survey confirms the importance of fastidious enteric Ad in infantile diarrhea (Ad 40, Ad 41) and suggests that Ad 31 produces a clinical syndrome indistinguishable from that caused by Ad 40 and Ad 41. The occurrence of Ad enteritis in patients admitted for unrelated illnesses well after initial hospitalization suggests that Ad is also an important cause of nosocomial enteritis in our hospital.

Hepatitis B-associated membranous glomerulonephritis in a child.

This appears to be the first reported case of membranous glomerulonephritis in a pediatric asymptomatic carrier of hepatitis B virus in North America. Routine immunofluorescent methods were used to identify the hepatitis B surface antigen in glomeruli. In addition, the glomerular immune deposits were searched for the known ultrastructural forms of the virus.

Counter-immunoelectro-osmophoresis for the detection of infantile gastroenteritis virus (orbi-group) antigen and antibody.

A moderatley sensitive, rapid, and economical test scheme for the detection of infantile gastroenteritis virus (IGV) in stool or antibody in serum has been developed and evaluated. The test scheme with minor modifications was an adaptation of a counter-immunoelectro-osmophoresis system we once used for the detection of hepatitis B antigen. Large numbers of stool samples may be screened during half a working day for the presence of IGV using reference antiserum to IGV prepared in guinea-pigs. Serological studies of a diagnostic but not epidemiological nature may also be performed with equal facility by this same test scheme using highly purified IGV antigen derived from stool.

Silver staining of DNA restriction fragments for the rapid identification of adenovirus isolates: application during nosocomial outbreaks.

The ultrasensitive photochemical silver stain for nucleic acids, described by Beidler et al. (1982), has been applied to the detection of adenovirus restriction fragments as a relatively rapid technique for the identification of virus isolates. In this study, restriction enzyme cleavage analysis was used to characterize adenovirus isolates from what appeared to be two nosocomial outbreaks. The first outbreak was thus shown to include two clusters of patients, and involved two serotypes Ad7c and Ad40. The second outbreak was unrelated and involved Ad35. Although restriction analysis does not replace serum neutralization as a routine method for typing adenoviruses, it is a much more rapid means of discriminating between different patient isolates, providing a current rather than retrospective analysis of a nosocomial outbreak. During the first outbreak, restriction analysis identified two distinct adenovirus serotypes from one patient--Ad7c from a nasopharyngeal aspirate and Ad41 from a stool specimen. Restriction analysis is also valuable for the sub-typing of virus isolates. In this study, the Ad40 and Ad41 isolates were shown to be variants of the respective prototype strains.

Enterovirus infections in the neonate.

A chart review was made of 24 neonates less than one month of age with culture-proven enteroviral infection. The seasonal distribution was summer and fall. An antecedent illness was common in the mother or other family members. One patient had a mild gastroenteritis. Three categories of severe disease were noted: (a) meningitis accounted for 50 per cent of the illnesses; (b) myocarditis for 25 per cent of the illnesses; and (c) the remainder presented with a severe sepsis-like illness. High mortality rate was associated with low birth weight and low gestational age.

Viruses that multiply in the gut and cause endemic and epidemic gastroenteritis.

BACKGROUND: Acute infectious diarrhea in young children is a leading cause of morbidity and mortality in developing countries. Even in developed countries, infectious enteritis is second only to respiratory infections as a cause of morbidity in early childhood. OBJECTIVE: To nominate the various viral agents that cause enteritis, discuss the pathogenesis, clinical features, epidemiology and diagnostic procedures employed. STUDY DESIGN: Pertinent literature was reviewed and the findings of investigations carried out on viral enteritis by various colleagues recalled. RESULTS: The viruses causing gastroenteritis include: Rotaviruses; Adenoviruses-especially Ad 31, Ad 40 and Ad 41; members of the Caliciviridae, e.g. Norwalk virus, Hawaii virus, Snow Mountain virus, Taunton virus, Southampton virus, Toronto virus (formerly mini-reovirus) and others; Astrovirus; Coronavirus; Torovirus; Cytomegalovirus (CMV) and possibly Picobirnavirus. Enteritis-producing viruses replicate in columar epithelial cells in the distal parts of villi of the small intestine. Two mechanisms are addressed to explain why diarrhea occurs. Clinically, the main expression of illness is a watery diarrhea that lasts 24 h to about 7 days. Vomiting is of shorter duration and may not always accompany the diarrhea. Fever is generally 38.5 degrees C. Virus is shed in the stool for about 3-7 days. Diagnostic procedures employ electron microscopy (EM), immune electron microscopy (IEM), enzyme-linked immunosorbent assay (ELISA), time-resolved fluoroimmunoassay (TR-FIA), latex agglutination, polyacrylamide gel electrophoresis (PAGE) and the polymerase chain reaction (PCR). CONCLUSION: In developed countries viral enteritis among young children may be up to three times more common than bacterial gut disease. With the exception of CMV enteric involvement, the stool is characteristically not bloody and white blood cells are not found. Patient management may involve the employment of IV replacement therapy to counter dehydration and electrolyte imbalance. Milder cases may be managed with oral rehydration.

Immunofluorescence in diagnosis of measles infections in children.

Nasopharyngeal cells of 24 patients diagnosed as being in the prodromal phase or with established measles were examined by indirect immunofluorescence microscopy for the presence of measles antigen. Eighteen patients were positive for measles antigen by this technique. In ten of the 18 patients it was necessary to remove masking globulins from the antigen-containing cells prior to staining. Results obtained by immunofluorescence were supported by cytologic and serologic findings. No virus isolations were achieved. Immunofluorescence microscopy with elution of adherent globulins offers the most rapid and sensitive method for the laboratory diagnosis of measles.

Failure to show mycoplasmas and cytopathogenic virus in rheumatoid arthritis.

Synovial needle biopsies, joint aspirates, and joint tissue obtained at open operation from 41 cases of rheumatoid arthritis were inoculated onto PPLO media, L-form medium, and cell cultures for the isolation of mycoplasmas, L-form bacteria, and viruses. Medium suitable for the isolation of 'T' strain mycoplasmas was not employed. No mycoplasmas, L-form bacteria, or cytopathogenic viruses were shown. Similar specimens from nine patients diagnosed as having Reiter's disease were examined in a like manner and yielded only one Mycoplasma hominis type 1 isolate from a knee joint biopsy. It is concluded that known strains of mycoplasma and bacterial L-forms do not play a direct role in early and established cases of rheumatoid arthritis. Some of the cell cultures used in this study contained mycoplasma contaminants. Bacterial contaminants were also encountered in occasional batches of L-form medium.

Comparison of immunofluorescence and isolation techniques in the diagnosis of respiratory viral infections of children.

The immunoflourescent antibody technique (IFAT) and cell culture isolation procedures were compared for their efficiency in the etiological diagnosis of viral respiratory illness in children. Before the IFAT was incorporated as a routine procedure, antisera used in the test were carefully calibrated to insure specificity. A study was then conducted in which 375 nasopharyngeal suctions were investigated by both IFAT and isolation for the presence of parainfluenza virus types 1, 2, and 3, respiratory syncytial, influenza A, and influenza B viruses. Methods already established in our hospital for patient management and specimen collection were not altered for the purposes of the study. The IFAT, as conventionally practiced in the detection of respiratory virus antigens, requires adequate numbers of ciliated epithelial cells. There were 68.5% specimens which contained cells suitable for IFAT, whereas 31.5% had either an insufficient number or inappropriate types of cells and could be used only for virus isolation. Cell-associated immunoglobulins were detected in 16% of those specimens with adequate cells. When all specimens were considered regardless of their cell population, IFAT was inferior to isolation in diagnostic efficiency. However, isolation complemented by IFAT resulted in a statistically significant increase in number of positive virus identifications. Under routine working conditions in a large pediatric hospital, it was found that IFAT could not replace isolation techniques but could, if used in conjunction with isolation, provide a significant overall increase in number of positive diagnoses. The time that the specimen was taken in relation to first symptoms was found to be an important variable with respect to the method most likely to succeed in virus identification.

Influenza A virus associated with acute encephalopathy.

During the period of February 1972 until February 1976, we documented six cases of influenza A-associated acute encephalopathy. The illnesses occurred during periods of influenza A activity in our community. The encephalopathy was invariably preceded by an upper respiratory tract infection, and, thereafter, patients soon became confused, vomited, and showed noticeable restlessness. Patients then followed either of two courses, some becoming comatose within 24 hours and others improving rapidly within three days or less. None of these patients exhibited the hepatic and biochemical abnormalities associated with Reye's syndrome. All patients survived but some had sequelae. The syndrome of influenza-associated acute encephalopathy deserves wider recognition.

Tuberculosis of the colon simulating carcinoma.

A case of tuberculosis mimicking carcinoma in the distal colon is reported. The difficulty in diagnosing a solitary tuberculous colonic lesion, a review of the literature, and a differential diagnosis are presented.

Rapid immunoblot method for diagnosis of acute Mycoplasma pneumoniae infection.

A rapid immunoblotting technique based on the IgM response to a major immunogenic protein is described for the diagnosis of Mycoplasma pneumoniae infection. Using results of the complement fixation test as the criterion for diagnosis, the rapid immunoblot method was positive in 95.7% of patients. The sensitivity was reduced to 81.9% if the test was performed on either single sera or acute sera only from serum pairs. Although the few sera that failed to demonstrate a positive IgM response were more likely to be from older patients, there was a consistent IgM response recorded for both younger (less than 20 years) and older (greater than or equal to 20 years) patients.

Oligosaccharide composition of calf rotavirus.

The oligosaccharides of the structural glycoprotein (VP7) of calf rotavirus were characterized. The precursor of VP7 produced in infected cells in the presence of tunicamycin migrated on SDS-polyacrylamide gels with an apparent molecular weight 6000 less than the glycosylated glycoprotein. Endoglycosidase (Endo) H digestion of the mature virus resulted in a decrease of 5000 in the molecular weight of VP7 in two discrete stages. Analysis of Endo H-treated, 3H-labelled digestion products of VP7 on Bio-Gel P-4 identified an oligosaccharide of molecular weight 1350 as the predominant form. Further treatment of the digest with mannosidase and analysis on Bio-Gel P-2 columns indicated that the oligosaccharide was digested into a free mannose and an oligosaccharide of molecular weight 400 in the ratio of 6:1. This indicates that the oligosaccharides of VP7 consist of four N-linked (Man)7 residues, two of which occupy more exposed and two more cryptic positions in the VP7 molecule.

Comparison of bovine, simian and human rotavirus structural glycoproteins.

The structural glycoproteins of calf (BDV 486), human (Wa) and simian (SA11) rotaviruses were compared for sensitivity to endoglycosidase (Endo) H. The calf and human virus glycoproteins were reduced by approximately 5000 molecular weight in two equal stages. The simian rotavirus glycoprotein sustained only one 2500 molecular weight decrease. The effect of the host cell on the viral oligosaccharide composition was examined. Endo H digests of calf rotavirus 82-124 extracted from stool and its progeny propagated and [35S]methionine-labelled in MA104 cells were compared. Endo H had the same effects on the glycoproteins, indicating that the nature of the host cell does not affect the oligosaccharide composition of the virus glycoproteins.

Significance of viral infections in severe combined immunodeficiency disease.

An analysis of a prospective study of viral infections in 12 patients with severe combined immunodeficiency is presented. Infections of viral etiology were common, with pulmonary and gastrointestinal infections being most frequent. Fourteen of 25 infections (56%) were nonsocomially acquired and 10 of 25 (40%) were community-acquired. The period of symptomatology and the duration of viral excretion were usually prolonged beyond those associated with disease in the general pediatric population. Pulmonary infections were associated with considerable morbidity and mortality. Gastrointestinal infections disrupted gastrointestinal function and possibly played a role in enteric Gram-negative bacillary sepsis. The inability of these patients to eradicate these viruses in the absence of immunologic reconstitution resulted in significant morbidity, often with a fatal outcome.

Diagnosis of fastidious enteric adenoviruses 40 and 41 in stool specimens.

Thirty-five stool specimens, collected over a 14-week period from pediatric gastroenteritis patients and shown to contain adenovirus by electron microscopy, were inoculated onto 293 and HeLa cells. Virus isolates were characterized by serum neutralization and restriction endonuclease cleavage analysis of viral DNA from infected cells. Adenovirus was isolated upon primary inoculation of 293 cells from all 35 specimens shown to contain adenovirus by electron microscopy. Fastidious adenoviruses 40 and 41 (Ad40 and Ad41) were found in 17 (49%) of the stool specimens, and 4 of these specimens contained a conventional species (Ad1, Ad1, Ad18, Ad31) as well as Ad40. This was first manifest by the observation that four of the isolates which initially grew only in 293 cells acquired the capacity to grow in HeLa cells upon subsequent passage. In each case, the conventional species was undetectable by DNA analysis in the original inoculum but was selected in 293 cells and became the only one detectable by the second passage. Four other specimens, containing Ad1 or Ad31 alone, failed to grow initially in HeLa cells but did grow in 293 cells. The results of this study demonstrate therefore that (i) 293 cells are more sensitive than HeLa cells for the isolation of conventional as well as fastidious enteric adenovirus species and (ii) identification of viruses from patient specimens should involve minimal passage of the virus in cell culture, as a single passage can result in misdiagnosis of the virus associated with the infection.