Isotype-specific antibody responses to acute Mycoplasma pneumoniae infection.

BACKGROUND: Mycoplasma pneumoniae-induced respiratory infections affect millions of patients and have been implicated in exacerbation of bronchial asthma. IgE may be involved in such exacerbations. While specific IgG and IgM responses to Mycoplasma pneumoniae are well described, the response of other isotypes is less known. PURPOSE: To determine whether specific IgE and what subclasses of IgG are formed in response to Mycoplasma pneumoniae infection. METHODS: We studied 20 patients with acute Mycoplasma pneumoniae infection, in whom the diagnosis was confirmed by a 16-fold increase in complement fixation titer between acute and convalescent serum samples. We developed an enzyme-linked immunosorbent assay (ELISA) for the determination of IgG, IgA, and IgM antibodies specific for Mycoplasma pneumoniae protein antigens. We used Western blotting to confirm the results of the ELISA and to detect Mycoplasma-specific IgG subclasses and IgE. RESULTS: Changes in Mycoplasma pneumoniae-specific IgG, IgA, and IgM were significant. Western blots of Mycoplasma pneumoniae antigens in 13 convalescent sera showed specific IgG in all, IgM in 11, IgA in 6, and IgE in 10. The IgG response consisted mainly of IgG1 and IgG3, and to a lesser degree of IgG2 and IgG4. CONCLUSIONS: We conclude that Mycoplasma pneumoniae infection is associated with a significant specific IgA and IgE response, in addition to the well-known responses of IgG and IgM. As IgE is involved in allergic reactions, the production of Mycoplasma pneumoniae-specific IgE may have a role in exacerbation of bronchial asthma.

Increasing incidence of adenovirus disease in bone marrow transplant recipients.

Adenovirus infections in 201 bone marrow transplant (BMT) recipients over 4 years were retrospectively reviewed. Forty-two patients (20.9%) had positive adenovirus cultures after BMT. There was a higher incidence of adenovirus infections in pediatric patients than in adults (31.3% vs. 13.6%, P = .003). In addition, the time of onset of adenovirus infection after transplant was earlier in pediatric patients (mean, < 30 days) than in adults (> 90 days). Adenovirus type 35 was the most common serotype identified. One-third of adenovirus-positive patients had definite or probable adenovirus disease. Moderate to severe acute graft-versus-host disease and isolation of adenovirus from two or more sites were significant risk factors for adenovirus disease. This report documents a higher incidence of both adenovirus infection and disease than do previous studies. Adenovirus may emerge as a more frequent pathogen as more high-risk BMT transplants are done.

Increasing rubella seronegativity despite a compulsory school law.

To determine if lower rubella susceptibility persisted five to seven years after immunization legislation, we retrospectively reviewed the serologic status of 341 outpatients from 1985 to 1987 in an inner-city school age population. Seronegative rates increased significantly during the two-year study period from 4.2 to 24.5 percent (17 percent overall). (Beta = 6.8%, 95% CI = 3.3, 10.3). Charts were reviewed for 57 of 58 seronegative and 114 seropositive controls. Estimates were then made to the population of 341 subjects. Those with documented rubella immunization had a seronegative rate of 13 percent compared to 19 percent if the immunization status was unknown. For patients who received care in our clinic for less than two years, 32 percent were seronegative compared to 10 percent for those treated greater than or equal to 2 years (odds ratio = 0.31, 95% CI = 0.16, 0.60). Among patients immunized in 1977 or 1978, 33 percent were seronegative compared to 7 percent immunized at other times (OR = 0.21, 95% CI = 0.07, 0.63). Factors associated with increased rubella seronegativity include immunization in 1977 or 1978 and lack of continuity of care in our clinic. Much of the increase remains unexplained.

Leukocyte tubuloreticular inclusions in Reye's syndrome.

Tubuloreticular inclusions (TRI) have been observed in the rough endoplasmic reticulum of blood lymphocytes and monocytes in two cases of Reye's syndrome initiated by influenza infections. Tubuloreticular inclusions are seen in these mononuclear leukocytes during the acute phase of illness, but not during convalescence. Since TRI have been demonstrated in peripheral mononuclear leukocytes in patients with acquired immunodeficiency syndrome, systemic lupus erythematosus, and certain viral infections including T-cell leukemia, it may be that the finding of TRI in Reye's syndrome reflects a viral infection and/or immune dysfunction, if such association is not proved to be fortuitous.

Outbreak of influenza A/USSR/77 at Marquette University.

An outbreak of influenzalike illness occurred at Marquette University, Milwaukee, Wisconsin, in February 1978. Epidemiologic and laboratory data indicate that the outbreak was due to influenza A/USSR/77 (N1H1) virus. A self-administered questionnaire inquiring about the presence and spectrum of illness was given to faculty members, dental students, and residents of an undergraduate dormitory. Age-specific attack rates were 61.5% for persons less than or equal to 22 years of age, 24.7% for those 23 or 24 years of age, and 9.7% for those greater than or equal to 25 years of age. This pattern of age-specific attack rates paralleled the age distribution of persons without hemagglutination-inhibiting antibody to influenza A/USSR/77 virus found in independent serosurveys. Prior swine influenza (H1N1) immunization provided no protection from illness in this outbreak. Past epidemic antibody titers in undergraduates were only weakly associated with clinical illness. The data on disease impact gathered in this study indicate that in a university setting influenza A/USSR/77 virus produced a short-lived outbreak of respiratory illness with a very high attack rate in young adults.

Testalgia associated with rubella infection.

Investigation of an outbreak of rubella on a college campus provided an opportunity to study the occurrence of orchitis, or testalgia, in male adolescents and young adults. Of 68 subjects with rubellla infection, five reported pain without swelling in one or both testicles lasting up to three days. Two of them had laboratory-confirmed rubella infection. Since the majority of all currently reported cases of rubella in the United States occur in persons 15 years of age and older, an increased awareness of rubella as a possible cause of testicular pain, and perhaps of orchitis, in postpubertal boys and men result in further characterization of this symptom.

Hemagglutination-inhibiting antibodies in vaccinated children with renal disease.

One year after immunization with a single 0.5-mL dose of influenza virus vaccine, serum samples from 30 children with renal diseases were tested for serum hemagglutination-inhibiting (HI) antibody titers to A/New Jersey/76, A/Victoria/75, and A/USSR/77. Eleven unvaccinated children with renal diseases formed a comparison group. In contrast to the comparison group (0/11), 53% (16/30) of the vaccinated group had a protective level of serum HI titers (greater than or equal 1:40) against A/New Jersey. A protective level of serum HI titer against A/Victoria was noted in 83% (25/30) of the vaccinated group, while 54% (6/11) of the unvaccinated group had similar HI titers. None had a detectable HI titer against A/USSR. A minor common cold-like illness occurred in seven of the 30 vaccinated children; one of these had exacerbation of nephrotic syndrome. The data suggest a good protection against influenza one year after vaccination in children with renal disease.

Influenza virus immunization. Antibody response and adverse effects in children with renal disease.

Before and four weeks after immunization with a single 0.5-ml dose of influenza virus vaccine, sera from 36 children with renal diseases were tested for serum hemagglutinating-inhibiting antibody (HAI) titers to A/New Jersey/76, A/Victoria/75, and A/Port Chalmers/73. Before immunization, 1:40 HI antibodies to A/New Jersey were noted in one child only, to A/Victoria in ten children (27%), and to A/Port Chalmers in 25/34 children (68%). Serum HAI titers increased fourfold or more (P less than .01) in 31/36 children (86%) after immunization. Neither the type of the renal disease nor therapy with prednisone had any effect on the rise of serum HAI titers (P less than .05). Of the seven children with preimmunization proteinuria, four had a transient rise in protein levels following immunization. None required an increased prednisone dose for exacerbation of nephrotic syndrome. Children with chronic renal problems should be protected against influenza.

Outbreak of influenza in a neonatal intensive care unit.

An outbreak of influenza A/Victoria/3/75 (H3N2) involving five infants in a neonatal intensive care unit is described. The clinical signs and symptoms were indistinguishable from those seen in bacterial sepsis. There was no evidence of meningoencephalitis. All infants recovered without any sequelae.

Reye syndrome. A correlated electron-microscopic, viral, and biochemical observation.

Liver biopsy specimens of two patients with Reye syndrome were examined for ultrastructural features, viral isolation, and urea-cycle enzyme activity. Concurrent presence of herpes-like virus and myxovirus/paramyxovirus was demonstrated by electron microscopy, and viral infections were confirmed by isolation or serologic tests. A concomitant hepatic ornithine transcarbamoylase deficiency was also noted. The pathogenesis in these instances seems to consist of an initial synergistic insult on the liver by mixed types of viruses and subsequent breakdown of urea cycle, Krebs cycle, and possible other hepatic functions. An exodus of glycogen granules into the hepatic spaces of Disse and sinusoids suggests that the viruses have injured the plasma membranes as well as the mitochondria of hepatocytes. Since Kapila et al reported similar disorders five years before Reye et al, the name of Kapila-Reye disease is suggested.

Chronic myopathy associated with coxsackievirus type A9. A combined electron microscopical and viral isolation study.

Virus-like crystalline structures in human skeletal muscles have been observed by many electron microspists, but no viruses have been isolated and identified in such cases. An 11-year-old girl who had had muscular weakness and physical retardation since early infancy died of pneumonia due to atrophy of diaphragmatic and intercostal muscles. Electron microscopy of these muscles revealed a heavy infiltration of picornavirus-like particles that measured 19 to 23 nm in diameter. Subsequent inoculation of primary human-amnion cells with a sonic-treated suspension of the patient's diaphragmatic muscle induced an enterovirus-like cytopathic effect. The isolate was identified with use of Lim-Benyesh--Meinick enterovirus typing serum pools as coxsackievirus Type A-9. This viral isolation supports the belief that the organized electron-dense particles in human muscle are indeed virions.