Cytomegalovirus as a frequent cause of Guillain-Barré syndrome

Neuromuscular Complications of SARS-CoV-2 and Other Viral Infections

In this article we review complications to the peripheral nervous system that occur as a consequence of viral infections, with a special focus on complications of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). We discuss neuromuscular complications in three broad categories; the direct consequences of viral infection, autoimmune neuromuscular disorders provoked by viral infections, and chronic neurodegenerative conditions which have been associated with viral infections. We also include discussion of neuromuscular disorders that are treated by immunomodulatory therapies, and how this affects patient susceptibility in the current context of the coronavirus disease 2019 (COVID-19) pandemic. COVID-19 is associated with direct consequences to the peripheral nervous system via presumed direct viral injury (dysgeusia/anosmia, myalgias/rhabdomyolysis, and potentially mononeuritis multiplex) and autoimmunity (Guillain Barré syndrome and variants). It has important implications for people receiving immunomodulatory therapies who may be at greater risk of severe outcomes from COVID-19. Thus far, chronic post-COVID syndromes (a.k.a: long COVID) also include possible involvement of the neuromuscular system. Whether we may observe neuromuscular degenerative conditions in the longer term will be an important question to monitor in future studies.

Myopericarditis complicated by pulmonary embolism in an immunocompetent patient with acute cytomegalovirus infection: a case report

Background

Primary acute cytomegalovirus infection in immunocompetent patients is common worldwide. Infection is most often asymptomatic or occurs sub-clinically with a self-limited mononucleosis-like syndrome. More rarely, the infection may lead to severe organ complications with pneumonia, myocarditis, pericarditis, colitis and hemolytic anemia. Recent cases of cytomegalovirus-associated thrombosis have also been reported sporadically in the medical literature.

Case presentation

We report here a case of simultaneous myopericarditis and pulmonary embolism in a 30-year-old man with no medical history. The patient was not immunocompromised. We discuss the possible role of acute cytomegalovirus infection in the induction of vascular damage and review relevant cases in the literature.

Conclusion

Thrombosis in patients with acute cytomegalovirus infection may be more frequent than is generally thought. Physicians need to be aware of the possible association between acute cytomegalovirus and thrombosis in immunocompetent patients, especially in the presence of severe systemic infection, as our case illustrates.

Primary cytomegalovirus infection in patients with Guillain-Barré syndrome

Guillain-Barré syndrome (GBS) is frequently associated with the presence of CMV-specific IgM-antibodies or CMV-DNA in serum. Detection of IgM-antibodies or viremia may indicate primary infection, but also reactivation or reinfection. We identified 46 GBS patients with detectable CMV-specific IgM- or IgG-antibodies, or both. Sera from these patients were tested for the presence of CMV-specific, low-avidity IgG-antibodies, which indicate primary infection that occurred <6 months before sample collection, and for the presence of CMV-DNA by polymerase chain reaction (PCR). Primary infection was identified by the presence of low-avidity IgG-antibodies in 9/46 (20%) or by detection of IgM-antibodies in the absence of IgG-antibodies in 1/46 (2%) patients. CMV-DNA was detectable in 17/46 (37%) sera. In contrast, CMV-DNA was detected in only 2% of sera from 46 age-matched patients with neuroborreliosis. The likelihood of viremia decreased in GBS patients significantly with increasing antibody-avidity (P=0.041). Detection of IgM-antibodies correlated with that of CMV-DNA in patients with low-avidity IgG-antibodies (P=0.048) but not in those with high-avidity IgG-antibodies (P=0.543). In 45 age-matched healthy controls, low-avidity IgG-antibodies and CMV-DNA were detected in only 2% and 0% of sera, respectively. Our findings further strengthen evidence for an association between CMV infection and GBS. Primary CMV infection was identified in almost one-fourth of patients with detectable CMV-specific antibodies. Nevertheless, endogenous reactivation and reinfection have to be considered also as relevant events associated with GBS.

Brief report: autistic disorder in three children with cytomegalovirus infection

Previous research has identified a relationship between autistic disorder (autism) and specific congenital infections. Three cases of congenital or perinatal cytomegalovirus (CMV) infection occurring in association with autism are described. Hypothetical mechanisms relating congenital infection, such as CMV, to the development of autism are discussed. A better understanding of the immunologic response to certain congenital infections may provide important information pertaining to the pathophysiology and etiology of autism in vulnerable individuals.

Cytomegalovirus mononucleosis as a cause of prolonged fever and prominent weight loss in immunocompetent adults

Four immunocompetent adults presented with protracted fever lasting > 6 weeks and severe weight loss, associated with primary cytomegalovirus (CMV) infection. Each patient had spleen enlargement, lymphocytosis and hypertriglyceridaemia, but recovered spontaneously. A further 20 immunocompetent patients with primary CMV infection were also reviewed, and all presented the usual clinical picture of CMV mononucleosis. It was concluded that CMV mononucleosis should be considered in the differential diagnosis in patients with prolonged fever and weight loss if lymphocytosis is present.

Infectious origins of, and molecular mimicry in, Guillain-Barré and Fisher syndromes

Guillain-Barré syndrome (GBS), characterised by limb weakness and areflexia, is the prototype of postinfectious autoimmune diseases, and Campylobacter jejuni is the most frequent antecedent pathogen. GBS subsequent to C jejuni enteritis is associated with a severe, pure motor axonal variant and IgG antibodies against GM1, GM1b, GD1a, or GalNAc-GDla, gangliosides expressed in human peripheral nerves. Lipopolysaccharides of C jejuni isolated from GBS patients have ganglioside-like epitopes. Cytomegalovirus is the most common viral antecedent infection. Patients with demyelinating GBS who have had a recent CMV infection have severe sensory deficits and anti-GM2 IgM antibody. CMV-infected fibroblasts express the GM2 epitope. Fisher syndrome (FS), characterised by ophthalmoplegia, ataxia, and areflexia, is a GBS variant associated with anti-GQ1b IgG antibody. GQ1b is enriched in the cranial nerves that innervate the extraocular muscles. Some patients develop FS after C jejuni infection, and the lipopolysaccharide present bears the GQ1b epitope. Molecular mimicry is a possible cause of GBS and FS.

Vaccination and autoimmunity-'vaccinosis': a dangerous liaison?

The question of a connection between vaccination and autoimmune illness (or phenomena) is surrounded by controversy. A heated debate is going on regarding the causality between vaccines, such as measles and anti-hepatitis B virus (HBV), and multiple sclerosis (MS). Brain antibodies as well as clinical symptoms have been found in patients vaccinated against those diseases. Other autoimmune illnesses have been associated with vaccinations. Tetanus toxoid, influenza vaccines, polio vaccine, and others, have been related to phenomena ranging from autoantibodies production to full-blown illness (such as rheumatoid arthritis (RA)). Conflicting data exists regarding also the connection between autism and vaccination with measles vaccine. So far only one controlled study of an experimental animal model has been published, in which the possible causal relation between vaccines and autoimmune findings has been examined: in healthy puppies immunized with a variety of commonly given vaccines, a variety of autoantibodies have been documented but no frank autoimmune illness was recorded. The findings could also represent a polyclonal activation (adjuvant reaction). The mechanism (or mechanisms) of autoimmune reactions following immunization has not yet been elucidated. One of the possibilities is molecular mimicry; when a structural similarity exists between some viral antigen (or other component of the vaccine) and a self-antigen. This similarity may be the trigger to the autoimmune reaction. Other possible mechanisms are discussed. Even though the data regarding the relation between vaccination and autoimmune disease is conflicting, it seems that some autoimmune phenomena are clearly related to immunization (e.g. Guillain-Barre syndrome). The issue of the risk of vaccination remains a philosophical one, since to date the advantages of this policy have not been refuted, while the risk for autoimmune disease has not been irrevocably proved. We discuss the pros and cons of this issue (although the temporal relationship (i.e. always 2-3 months following immunization) is impressive).

Herpesviruses--a rationale for antiviral treatment in multiple sclerosis

In multiple sclerosis (MS), the extensive and long lasting search for viruses or other pathogens has hitherto failed to identify a common etiological agent. However, the beneficial effects by interferon-beta treatment in MS, although suggested to depend mainly on immunomodulation, might lend support to a viral involvement in the pathogenesis. The human herpesviruses have attracted interest since their recurrent modes of infection share some similarity with the relapsing-remitting course of MS, most members are readily detected within the brain, and several of these viruses may induce demyelination within the central nervous system in human hosts as well as in animal models. Accumulated diagnostic and epidemiological data are compatible with a role for the herpesviruses as possible cofactors rather than etiological agents, and recent studies showing early neuronal damage in MS patients focus attention on the neurotropic alpha-herpesviruses. Antiviral treatment trials with safe and effective drugs such as valaciclovir offer a possibility of testing the hypotheses concerning herpesviral involvement in MS.

Ganciclovir and foscarnet efficacy in AIDS-related CMV polyradiculopathy

Cytomegalovirus (CMV) polyradiculopathy is a rare complication of AIDS in which ascending motor weakness, sensory loss and urinary retention are associated with polymorphonuclear pleocytosis and positive CMV polymerase chain reaction in the cerebrospinal fluid (CSF). We describe three patients with this syndrome. One patient's paresis improved after ganciclovir therapy. Another patient deteriorated despite foscarnet treatment, but improved after ganciclovir was added. The third patient died from ascending paralysis despite ganciclovir-foscarnet combination. Reviewing the literature, we conclude that antiviral treatment reduced mortality from 100 to 22%. In patients with ascending paralysis treatment, failure may be caused by viral drug resistance, at least in some patients. Risk factors for treatment failure are preceding monotherapy for other CMV diseases or persistent CSF pleocytosis on serial CSF analysis. We suggest that these patients should therefore be treated with the alternative drug or a ganciclovir-foscarnet combination therapy.

[Guillain-Barré syndrome complicating cytomegalovirus infection in an immunocompetent adult]

Guillain-Barré syndrome is a rare complication of cytomegalovirus infection in the healthy adult. We report a new case with good spontaneous outcome. Cytomegalovirus has been recognized in about 15% of Guillain-Barré syndromes. Clinical and biological presentation, and outcome are common and prognosis is often good. Etiopathogenic mechanism is unclear.

Myelin- and microbe-specific antibodies in Guillain-Barré syndrome

We surveyed the frequency of reported infections and target autoantigens in 56 Guillain Barré syndrome (GBS) patients by detecting antibodies to myelin and microbes. Sulfatide (43%), cardiolipin (48%), GD1a (15%), SGPG (11%), and GM3 (11%) antibodies were the most frequently detected heterogenous autoantibodies. A wide spectrum of antimicrobial IgG and IgM antibodies were also detected; mumps-specific IgG (66%), adenovirus-specific IgG (52%), varicella-zoster virus-specific IgG (46%), and S. pneumoniae serotype 7-specific IgG (45%) were the most prevalent. Our results indicate that polyclonal expansion of physiologic and pathologic antibodies and/or molecular mimicry likely occurs following infection and is related to other autoimmune factors in the etiology of GBS. Although no single definitive myelin-specific autoantibody was identified, our results suggest a unique pattern of reactivity against autoantigens.

Cytomegalovirus infection in the pregnant women

Cytomegaloviruses (CMV) commonly infect man but overt disease only occurs in few patients; in the vast majority the infection is subclinical. We report on a HIV-negative pregnant woman. She suffered from a life-threatening ulcerating colitis due to CMV infection for which laparotomy was indicated. The case history is presented and suggestions are given for the surgical treatment of gastrointestinal complications such as haemorrhage, toxic colitis and perforation. Although CMV disease usually occurs in immunocompromised patients such as AIDS patients and transplant recipients, one should always keep the possibility of CMV infection in mind. The gastrointestinal tract is one of the sites of infection where the colon and terminal ileum are most frequently involved in complications such as bleeding and perforation. Gastrointestinal complications of CMV infection, although rare, can be life threatening and often require extensive surgery.

Clinical signs in severe Guillain-Barré syndrome: analysis of 63 patients

Clinical data are presented of 63 artificially ventilated Guillain-Barré patients. About half of them had an antecedent event. In 57% the disease was heralded by sensory symptoms. The mean progressive phase lasted 12 days, the plateau 12 days and the recovery phase 568 days. In all patients one or more cranial nerves were involved, most often leading to facial palsy or difficulties in swallowing. Three-quarters of the patients had sensory signs, proprioceptive more often than superficial. Autonomic disturbances were common, especially hypertension and tachycardia. Twenty-two percent of the patients were severely confused in the first weeks of the disease. Laboratory examination showed atypical lymphocytes in the blood of 37% of patients and disturbed hepatic function tests in 79%. CSF protein level was elevated in all patients, with a mean value of 1.5 g/l.

Clinical and serological studies in a series of 45 patients with Guillain-Barré syndrome

We retrospectively reviewed the clinical files of 45 Guillain-Barré syndrome (GBS) patients admitted to our Department between 1979 and 1989. The age distribution was bimodal with a first peak in young adults (20-40 years), and a second one between 60 to 70 years. Seasonal distribution showed a late fall and a hivernal predominance. Three patients experienced a second attack of GBS 2-9 years after the first one. Thirty-one (69%) presented antecedent events, most often a respiratory tract infection (n = 20) or enteritis (n = 6). Serological studies were systematically performed, including antibody titers against herpes simplex virus, Epstein-Barr virus, cytomegalovirus (CMV), respiratory syncytial virus, human immunodeficiency virus, Mycoplasma pneumoniae, Campylobacter jejuni/coli and cardiolipin. These studies showed the presence of antibodies indicative of a CMV primary infection in 22% cases and of a Campylobacter jejuni/coli infection in 13%. Co-infection was observed in 3 cases. Serology remained negative in 12 patients with a preceding respiratory infection. There was no correlation between serology and the severity of the disease. Absence of antecedent events and of positive anti-infectious serology was observed in only 10 patients.

Virus-specific serum IgG, IgM, and IgA antibodies in cytomegalovirus mononucleosis patients as determined by immunoblotting technique

The immune response to individual human cytomegalovirus (CMV) structural polypeptides was studied in paired sera from 15 adult CMV mononucleosis (CMV-MN) patients and healthy controls by immunoblotting technique (IB). IgM and IgG antibodies to at least 11 structural polypeptides with molecular weights of 28K, 49K, 55K, 57K, 66-70K, 82K, 87K, 110K, 150K, 205K, and 235K were detected in the patients' sera in the serum sample obtained in the acute phase of the disease. IgA antibodies to polypeptides with molecular weights of 66-70K, 82K, 110K, and 150K were also detected in these sera. In healthy seropositive adults, IgG antibodies with the same molecular weight polypeptides, excluding the 205K and 235K polypeptides, were detected as in convalescent CMV-MN patients. A prominent reactivity of IgM and IgA antibodies to the 66-70K and 150K polypeptides was noted in the acute sera from all the CMV-MN patients examined, but not in a number of late convalescent sera. The potential implications of these findings in the development of specific serological tests are discussed.

Viral diseases involving the liver

Even though HAV, HBV and HNANB viruses are responsible for most of the viral hepatitis cases, many other viruses have been reported to cause hepatic injury. These viruses may involve the liver, either as part of a systemic illness (e.g. EBV, CMV, HSV) or as the primary target organ (e.g. yellow fever virus, Lassa fever virus, Ebola virus). Clinically overt hepatocellular dysfunction is rare in such viral infections. Biochemical disturbance of hepatic functions shown, for example, by rises in AST and ALT, is a frequent event and indicates hepatic damage. Morphological changes of the liver include varying degrees of hepatic necrosis with a paucity of inflammatory activities. Intranuclear or cytoplasmic inclusion bodies may be characteristic findings in these diseases. Laboratory diagnosis depends upon serology and liver histology. Treatment is still largely supportive in most of these diseases, although recent trials of antiviral agents show promise against some viruses. Chronic sequelae, such as cirrhosis or hepatocellular cancer, are not encountered. More work is needed to elucidate the pathogenesis of hepatic injury in these illnesses.

Viral infections of the nervous system

Neurotropic viruses cause a number of important infectious syndromes including encephalitis, myelitis, meningitis, and radiculopathy. In this review, the biology of conventional and unconventional viruses is examined. The host immune response to viruses is discussed, and patterns of viral pathogenesis are explained. The clinical features, laboratory findings, management of important viral infections, such as herpes simplex encephalitis and epidemic encephalitis, are presented. Post-infection syndromes, such as the Guillain-Barré syndrome, and chronic viral infections, such as those causing progressive multifocal leukoencephalopathy and subacute sclerosing panencephalitis, are discussed. Current knowledge concerning the nature of unconventional virus-like agents of the spongiform encephalopathies, including kuru and Creutzfeldt-Jakob disease, is summarized. Finally, viral infections of immunocompromised patients and the possible role of viruses in the newly described acquired immunodeficiency syndrome (AIDS) are examined.

Hepatitis A virus immunoglobulin M antibody in acute neurological disease

Sera from 167 patients with Guillain-Barré syndrome, 224 patients with other neurological diseases, and 10 normal subjects were tested for hepatitis A virus-specific immunoglobulin M antibodies. Two patients with classic Guillain-Barré syndrome and 1 patient with acute myeloradiculopathy had high titers of virus-specific IgM antibody. All three patients had jaundice and laboratory evidence of liver involvement before the onset of the neurological disease. None of the other sera from patients with Guillain-Barré syndrome or control subjects were positive for hepatitis A virus.

Human cytomegalovirus specific IgA antibodies detected by immunoperoxidase assay in serum of patients with cytomegalovirus infections

Cytomegalovirus (CMV)-specific IgA antibodies were determined by an immunoperoxidase assay in sequential serum samples of 10 patients with CMV infection in order to evaluate the feasibility of the use of this technique for diagnosis. In parallel, IgM and IgG antibodies to CMV were studied by enzyme-linked immunosorbent assay (ELISA) and by the immunoperoxidase assay, respectively. CMV IgA antibodies were detected in all 10 CMV patients studied. Specific IgM was detected earlier than IgA in only one of these ten patients. No CMV-specific IgA antibodies (titer less than 2) were detected in 45 medical students. Neither were they found in paired sera of 5 patients with herpes simplex infection, 5 patients with varicella, 6 patients with zoster and 2 patients with Epstein-Barr virus infection. The potential application of the indirect immunoperoxidase IgA assay for serodiagnosis of CMV infections is discussed.

Immunofluorescent staining of nuclear antigen in lymphoid cells transformed by Herpesvirus papio (HVP)

An improved fixation method for antigen detection in lymphoblastoid cells is described. Herpesvirus papio nuclear antigen (HUPNA) could be stained in several transformed lymphoid cell lines by anti-complement immunofluorescence (ACIF). Antibody to HUPNA was detected in many human sera containing antibodies to Epstein-Barr virus capsid and nuclear antigen (EBNA). Rheumatoid arthritis sera showed a high incidence of both anti-EBNA and anti-HUPNA antibodies.

Antibody response to cytomegalovirus: a comparison between adult patients with neurological disease and uncomplicated infection

Cytomegalovirus (CMV) infection in adults can cause neurological diseases such as the Guillain--Barré syndrome (GBS) and myelitis. The mechanism leading to the development of neurological damage is, however, still unknown. We have investigated the possibility that an abnormal humoral immune response, either weak or hyperactive, could be the cause. The antibody response of four patients with a primary CMV followed by neurological symptoms was compared to that of four age-matched controls with an uncomplicated infection. IgG and IgM antibodies to CMV early antigens (EA), late antigens (LA), and IgG antibodies to CMV immediate early antigens (IEA) were measured in consecutive serum samples. Comparison of titers indicated a longer time lapse between the onset of CMV infection and the development of symptoms in the group with neurological disease. We found no conclusive evidence of an abnormal humoral immune response to CMV in the patients with neurological disease compared to the patients with an uncomplicated infection.

Role of infection in Guillain-Barré syndrome: laboratory confirmation of herpesviruses in 41 cases

Serological evidence of either acute cytomegalovirus (CMV) or Epstein-Barr virus (EBV) infection was sought in a large series of patients with Guillain-Barré syndrome (GBS) and control subjects. Using an indirect immunofluorescent technique, IgM antibody directed against CMV was found in the serum of 33 of 220 GBS patients. The CMV-positive patients were mainly young adults (average age, 25.6 years), previously healthy, and the most common prodromal illness was mild coryza. Alternations in serum CMV IgM antibody level closely paralleled the patients' clinical course. Persistently elevated titers were found in patients with severe and protracted paralysis, whereas rapid disappearance of virus-specific IgM characterized benign cases. Striking time clusters of CMV-seropositive patients were found during three periods between January, 1971, and October, 1973. In a parallel study, EBV-specific IgM was found in 8 of 100 GBS patients (8%). All 8 also had heterophil antibodies. Thus, EBV and CMV appear related to a substantial number of cases of this primary demyelinating disease and, to date, are the two most common agents we have been able to link with GBS.

Growth of murine cytomegalovirus in murine and heterologous brain cell cultures. Brief report

Murine cytomegalovirus (MCMV) produced a cytopathic effect in mouse brain, guinea pig embryonic brain, human brain and fibroblast cells. Virus-specific antigen was detected by immunofluorescence in these cells after primary infection with MCMV. MCMV also replicated in ouse embryo brain and guinea pig brain cells. Although definite evidence of MCMV replication could not be demonstrated in human cells, MCMV infectivity was maintained for 12 days in human cell cultures.

Mycoplasma antibody in Guillain-Barré syndrome and other neurological disorders

Counterimmunoelectrophoresis (CIEP) was used to determine precipitating antibodies to Mycoplasma pneumoniae retrospectively in sera from 100 patients with Guillain-Barré syndrome (GBS), 125 medical and neurological controls, and 40 normal individuals. Sera from 7 patients produced precipitin lines. These positive cases included 5 patients with GBS, 1 with acute cerebellar ataxia, and 1 with acute disseminated encephalomyelitis. A complement-fixation test performed with the same antigen showed titers to M. pneumoniae of 1:512 or greater in these 7 sera. In contrast, sera from other patient controls and normal individuals were negative by CIEP and had only low mycoplasma complement-fixation antibody titers. No distinguishing clinical features separated the 5 seropositive GBS patients from the whole group except for their young age, which parallels that for human mycoplasma infection in general. Additional laboratory findings consistent with acute mycoplasma infection were demonstrated in 6 of the 7 seropositive patients.

Guillain-Barré syndrome associated with Epstein-Barr virus in a cytomegalovirus-negative patient

Epstein-Barr virus and cytomegalovirus have both been associated with Guillain-Barré syndrome after antibody investigations in several patients. In the teenage female patient in this present report, Guillain-Barré syndrome following infectious mononucleosis was associated with sero-conversion against Epstein-Barr virus but not cytomegalovirus. The findings are consistent with the hypothesis that Epstein-Barr virus might be an etiological agent for the Guillain-Barré syndrome and that infection with cytomegalovirus is not a requisite for the syndrome.

Amplified direct immunofluorescence (AMDI) for detection of Epstein-Barr virus nuclear antigen

Low antigen concentrations could be identified in human cells by sequential application of (a) FITC-labeled human antibodies at high dilution, (b) rabbit antiserum to the hapten fluorescein isothiocyanate (FITC), and (c) FITC-anti-rabbit globulin. The high specificity of direct immunofluorescence (a) was not affected by the amplifying steps (b) and (c). Using this AMDI technique Epstein-Barr (EB) virus nuclear antigen (EBNA) could be specifically stained with human sera up to a dilution of 1 : 4000. Owing to the high dilutions applied, unwanted antibody reactivity in the FITC-labeled serum could be blocked by preincubating with unlabeled undiluted human sera. Thus EBNA was selectively stained in EB virus producer cells. Moreover, EBNA was specifically detected in human tumor biopsy material by the use of AMDI.