Fatal ECHO 24 infection in a patient with hypogammaglobulinemia: relationship to dermatomyositis-like syndrome

Rubella virus chronic inflammatory disease and other unusual viral phenotypes in inborn errors of immunity

Infectious susceptibility is a component of many inborn errors of immunity. Nevertheless, antibiotic use is often used as a surrogate in history taking for infectious susceptibility, thereby disadvantaging patients who present with viral infections as their phenotype. Further complicating clinical evaluations are unusual manifestations of viral infections which may be less familiar that the typical respiratory viral infections. This review covers several unusual viral phenotypes arising in patients with inborn errors of immunity and other settings of immune compromise. In some cases, chronic infections lead to oncogenesis or tumor-like growths and the conditions and mechanisms of viral-induced oncogenesis will be described. This review covers enterovirus, rubella, measles, papillomavirus, and parvovirus B19. It does not cover EBV and hemophagocytic lymphohistiocytosis nor lymphomagenesis related to EBV. EBV susceptibility has been recently reviewed. Our goal is to increase awareness of the unusual manifestations of viral infections in patients with IEI and to describe treatment modalities utilized in this setting. Coincidentally, each of the discussed viral infections can have a cutaneous component and figures will serve as a reminder of the physical features of these viruses. Given the high morbidity and mortality, early recognition can only improve outcomes.

Characteristics and therapy of enteroviral encephalitis: case report and systematic literature review

OBJECTIVES

Enterovirus (EV) is a frequent cause of encephalitis. The optimal therapeutic approach remains a matter of debate. We present the case of an immunosuppressed patient with EV encephalitis treated successfully with intravenous immunoglobulin (IVIG) and report the results of a systematic review on the characteristics of EV encephalitis, as well as the safety and efficacy of IVIG therapy.

METHODS

A systematic review was conducted using the PubMed, Cochrane Database, BIOSIS Previews, and ClinicalTrials.gov databases to identify all reports on patients with EV encephalitis as of December 31, 2020. The main outcomes assessed were the efficacy and safety of the respective therapeutic approach.

RESULTS

A total of 73 articles were included: one prospective trial, one retrospective and prospective case series, one purely retrospective case series, and 70 case reports. The case reports included a total of 101 patients. Immunosuppressed patients were at higher risk of contracting EV encephalitis and experiencing a fatal course. Hypogammaglobulinaemia particularly predisposes to EV disease, even with a moderate reduction in serum IgG levels. IVIG therapy in the immunosuppressed may confer a survival advantage.

CONCLUSIONS

IVIG therapy is rarely associated with severe adverse events and may be considered in immunosuppressed patients with EV encephalitis. Future trials should investigate the optimal IVIG dosing and route of application, the benefit of antibody-enriched IVIG preparations, and the serum immunoglobulin level that should trigger prophylactic replacement.

Enteroviral Infection in a Patient with BLNK Adaptor Protein Deficiency

B-cell linker (BLNK) protein is a non-redundant adaptor molecule in the signaling pathway activated by (pre) B-cell antigen receptor signals. We present two siblings with a homozygous deleterious frameshift mutation in BLNK, resulting in a block of B cell development in the bone marrow at the preB1 to preB2 stage, absence of circulating B cells and agammaglobulinemia. This is the first description of an enteroviral infection associated arthritis and dermatitis in a patient with BLNK deficiency.

Clinical, neuropathological and radiological evidence for a rare complication of rituximab therapy

We report a rare case of myofasciitis and meningitis with deafness caused by systemic enterovirus infection in the setting of hypogammaglobulinaemia induced by rituximab. Whilst effective and generally safe, anti- CD 20 antibody therapy is increasingly recognised to result in unusual infectious complications to be considered in a treated patient presenting with neurological symptoms. These cases may pose diagnostic difficulties and can have atypical presentations. We present this rare complication of rituximab therapy, with histopathological confirmation of myofasciitis. In the older literature, enterovirus associated myofasciitis may have erroneously been termed dermatomyositis and we review the literature to demonstrate this important nosological point.

Primary B cell immunodeficiencies: comparisons and contrasts

Sophisticated genetic tools have made possible the identification of the genes responsible for most well-described immunodeficiencies in the past 15 years. Mutations in Btk, components of the pre-B cell and B cell receptor (lambda5, Igalpha, Igbeta), or the scaffold protein BLNK account for approximately 90% of patients with defects in early B cell development. Hyper-IgM syndromes result from mutations in CD40 ligand, CD40, AID, or UNG in 70-80% of affected patients. Rare defects in ICOS or CD19 can result in a clinical picture that is consistent with common variable immunodeficiency, and as many as 10% of patients with this disorder have heterozygous amino acid substitutions in TACI. For all these disorders, there is considerable clinical heterogeneity in patients with the same mutation. Identifying the genetic and environmental factors that influence the clinical phenotype may enhance patient care and our understanding of normal B cell development.

Hypogammaglobulinaemia

This article reviews the primary immunodeficiencies that result in hypogammaglobulinemia or predominantly antibody deficiency disorders. This group makes up the largest proportion of patients with primary immunodeficiency. Significant advances have been made in understanding the molecular basis and clinical characteristics of patients with the more severe forms of antibody deficiency in the last 6 years. Recognition of these disorders remains poor with significant diagnostic delay. The milder forms of antibody deficiency disorders, especially those with normal total serum immunoglobulin G levels, remain poorly characterized and understood. Further work remains to be done in understanding and recognizing these syndromes to benefit patient care and foster further knowledge of the immune system.

X-linked agammaglobulinemia: report on a United States registry of 201 patients

X-linked agammaglobulinemia (XLA) is a primary immunodeficiency caused by mutations in the gene for Bruton tyrosine kinase (BTK) that result in the deficient development of B lymphocytes and hypogammaglobulinemia. Because the disorder is uncommon, no single institution has had sufficient numbers of patients to develop a comprehensive clinical picture of the disorder. Accordingly, a national registry of United States residents with XLA was established in 1999 to provide an updated clinical view of the disorder in a large cohort of patients. A total of 201 patients were registered by 66 physicians. The estimated birth rate for the 10-year period of 1988-1997 was 1/379,000. Infection was the most common initial clinical presentation (85%), followed by a positive family history (41%) and neutropenia (11%). Although the average age of diagnosis was younger in patients with a positive family history (mean, 2.59 yr) than in patients with a negative family history (mean, 5.37 yr) (p < 0.001), only 34.5% of patients with a positive family history at the time of their birth were diagnosed before clinical symptoms developed-that is, based on family history alone. Seventy percent of patients had at least 1 episode of otitis, 62% at least 1 episode of pneumonia, 60% at least 1 episode of sinusitis, 23% at least 1 episode of chronic/recurrent diarrhea, 21% at least 1 episode of conjunctivitis, 18% at least 1 episode of pyoderma and/or cellulitis, 11% at least 1 episode of meningitis/encephalitis, 10% at least 1 episode of sepsis, 8% at least 1 episode of septic arthritis, 6% at least 1 episode of hepatitis, and 3% at least 1 episode of osteomyelitis. Fourteen of 201 (6.9%) patients were dead at the time they were entered in the Registry. However, in a prospective 4 /4-year follow-up of living patients, only 3/80 (3.75%) patients died. Causes of death included disseminated enterovirus infection (n = 6), pulmonary insufficiency (n = 5), adenovirus infection (n = 1), sepsis (n = 1), acquired immunodeficiency disease syndrome (AIDS) (n = 1), myocarditis (n = 1), hepatitis (n = 2), and stem cell transplantation (n = 1).

Genetic analysis of patients with defects in early B-cell development

Approximately 85% of patients with defects in early B-cell development have X-linked agammaglobulinemia (XLA), a disorder caused by mutations in the cytoplasmic Bruton's tyrosine kinase (Btk). Although Btk is activated by cross-linking of a variety of cell-surface receptors, the most critical signal transduction pathway is the one initiated by the pre-B cell and B-cell antigen receptor complex. Mutations in Btk are highly diverse, and no single mutation accounts for more than 3% of patients. Although there is no strong genotype/phenotype correlation in XLA, the specific mutation in Btk is one of the factors that influences the severity of disease. Mutations in the components of the pre-B cell and B-cell antigen receptor complex account for an additional 5-7% of patients with defects in early B-cell development. Patients with defects in these proteins are clinically indistinguishable from those with XLA. However, they tend to be younger at the time of diagnosis, and whereas most patients with XLA have a small number of B cells in the peripheral circulation, these cells are not found in patients with defects in micro heavy chain or Igalpha. Polymorphic variants in the components of the pre-B cell and B-cell receptor complex, particularly micro heavy chain and lambda5, may contribute to the severity of XLA.

Oligoclonal expansion of circulating and tissue-infiltrating CD8+ T cells with killer/effector phenotypes in juvenile dermatomyositis syndrome

Although triggering by infectious agents and abnormal immune responses may play some role in the pathogenesis of juvenile dermatomyositis syndrome (JDMS), the precise mechanism of muscle destruction and vascular damage is largely unknown. In this study, we tried to elucidate the role of cytotoxic T cells in two patients with JDMS, who were diagnosed based on the characteristic symptoms, laboratory data, MRI findings and electromyographic patterns. Peripheral blood T cell phenotypes were determined by flow cytometry, using mAbs against specific T cell receptor (TCR) Vbetas. Complementarity-determining region3 (CDR3) size analysis was performed by gene scanning of CDR3 polymerase chain reaction (PCR) amplification products specific for each Vbeta. Subsequently, CDR3 nucleotide sequences were obtained after cloning of the predominant products. The distribution of lymphocytes infiltrating the muscle tissue was analysed by immunohistochemistry. In both patients examined, a unique combination of TCR Vbeta repertoires was increased within the CD8+ T cells. These subpopulations expressed a characteristic phenotype, indicating that they are memory/effector T cells with killer functions. At the same time, immunohistological and molecular biological examinations of the biopsied muscle samples revealed that identical CD8+ T cell clones with identical phenotypes/TCR Vbeta infiltrated within the inflammatory tissue, in particular around vessels. These findings indicate that oligoclonal expansion of CD8+ T cells plays a central role in the pathogenesis of muscle injury in the juvenile form of dermatomyositis syndrome and may provide a useful clinical parameter of disease activity and responsiveness to anti-inflammatory therapy.

Myoglobinuria

Myoglobinuria refers to an abnormal pathologic state in which an excessive amount of myoglobin is found in the urine, imparting a cola-like hue, usually in association with myonecrosis and a clinical picture of weakness, myalgias, and edema. Myoglobinuria is produced by multiple causes: any condition that accelerates the use or interferes with the availability of oxygen or energy substrates to muscle cells can result in myoglobinuria, as can events that produce direct muscle injury, either mechanical or chemical. Acute renal failure is the most serious complication, which can be prevented by prompt, aggressive treatment. In patients surviving acute attacks, recovery of muscle and renal function is usually complete.

X-linked agammaglobulinemia. A clinical and molecular analysis

X-linked agammaglobulinemia (XLA), characterized by a profound deficiency of B lymphocytes due to an arrest in B lymphocyte development, is caused by mutations in the gene encoding Btk (Bruton tyrosine kinase). The BTK gene has been cloned and the genomic organization determined. BTK codes for 19 exons and is expressed in all hematopoietic cell lineages but is selectively down-regulated in T lymphocytes and plasma cells. The different Btk domains include PH, TH, SH3, SH2, and the kinase (SH1) domains. Btk, a cytoplasmic protein tyrosine kinase, is involved in cell signaling, although the precise pathway remains elusive. Mutation analysis has been performed in 236 families representing 282 patients. Mutations are scattered throughout the gene and consist of missense, nonsense, and splice site mutations as well as deletions and insertions. The major consequence of nonfunctional Btk appears to be a delay or block of the development of pro-B cells to pre-B cells and then to mature lymphocytes. Because IgG is actively transported across the placenta, affected newborns have normal levels of serum IgG at birth followed by gradually decreasing IgG levels and development of hypogammaglobulinemia and increased susceptibility to infections. Bacterial infections are the most common clinical manifestation. Resistance to viral infection is intact, except for an unusual susceptibility to infections with enteroviruses that may result in vaccine-related paralytic poliomyelitis or a dermatomyositis-meningoencephalitis syndrome. The diagnosis of XLA is based on the presence of lymphoid hypoplasia, markedly reduced serum levels of all 3 major classes of immunoglobulins, failure to make antibody to antigenic stimulation, and almost complete absence of B lymphocytes in the peripheral blood. Carrier detection and prenatal diagnosis are possible. The prophylactic infusion of high-dose intravenous immunoglobulin (IVIG) and the use of antibiotics have markedly improved the long-term prognosis of patients with XLA.

Genetic immunodeficiencies: cutaneous manifestations and recent progress

In recent years, remarkable progress has been made in elucidating the pathophysiology of genetic immunodeficiency disorders. Dermatologic manifestations are prominent in these conditions; because of advances in diagnosis and therapy, patients are living longer, increasing the likelihood that dermatologists will encounter patients with these diseases. The genes of many of these disorders have been cloned, including chronic granulomatous disease, X-linked immunodeficiencies, and myeloperoxidase deficiency. Understanding the regulation and function of these genes will not only affect patients with these rare disorders, but may provide an insight into common dermatologic conditions, such as eczema and cutaneous infection. Diagnosis, dermatologic manifestations, and therapy are discussed.

Laboratory evaluation of the inflammatory myopathies

The laboratory plays an important role in the diagnosis, evaluation, and classification of the heterogeneous group of diseases known as the IIM, which are characterized by chronic muscle inflammation. Serial measurements of the levels of muscle-derived enzymes in serum are the traditional laboratory studies used to follow the clinical course of patients with IIM, although other laboratory tests can also be useful in assessing myositis disease activity. Several markers of immune system activation, including cytokines and lymphocyte markers, show promise as possibly more sensitive measures of myositis disease activity. Discovery of a unique group of MSAs over the past decade has provided an immunologic basis for defining relatively homogeneous subsets of patients who share similar clinical features, disease courses, and responses to therapy. Future investigations of novel immunologic activation markers, as well as the cloning and expression of target autoantigens of the MSAs, should allow better diagnostic assays, enhanced prognosis, and a better understanding of the pathogenesis of these disorders.

Childhood exanthems. Old and new

Exanthems are a common cause of rashes in children. Several recent developments have sparked a renewed interest in this group of diseases, including the identification of parvovirus B19 and human herpesvirus 6 as the causative agents of erythema infectiosum and roseola infantum. The resurgence of measles as a childhood exanthem has caused a re-examination of current immunization practices. The most common and clinically significant exanthems are discussed, with an emphasis on new findings, origins, clinical manifestations, differential diagnosis, and management.

Caseating cutaneous granulomas in a patient with X-linked infantile hypogammaglobulinemia

A 34-year-old man with X-linked infantile hypogammaglobulinemia, bronchiectasis, and chronic liver disease had a papular eruption on the trunk and upper extremities. A biopsy specimen revealed caseating granulomas, but special stains, cultures, and electron microscopy failed to reveal an infectious organism. Immunohistochemistry showed that the lymphocytes within the granulomas were almost exclusively of the CD8+ cytotoxic/suppressor T phenotype. Phenotypic analysis of the circulating lymphocytes showed normal numbers of CD4+ (helper/inducer) and CD8+ T cells, whereas B cells were undetectable. Other examples of noninfectious granulomatous disease have been reported in patients with primary hypogammaglobulinemia, but this is the first case of caseating cutaneous granulomatous disease to be reported in a patient with X-linked infantile hypogammaglobulinemia.

Common variable immunodeficiency: the disorder and treatment

A case of common variable immunodeficiency, a relatively rare disorder, is presented. This case was complicated by the presence of an anti-IgA antibody in the patient's serum and a history of a possible anaphylactic reaction to a prior intravenous infusion of gamma-globulin. Common variable immunodeficiency is actually a heterogeneous group of demonstrable immunoglobulin deficiencies that have in common low levels of most immunoglobulin isotypes, the inability to form antibodies to antigen, an absence of gross defects in cell-mediated immunity, and the presence of recurrent bacterial infections. The history of immunoglobulin deficiency and its treatment is reviewed. Although the primary therapy for common variable immunodeficiency is gamma-globulin replacement, ancillary measures such as early treatment of infections with antibiotics are also important. Intravenous gamma-globulin replacement therapy is preferred to intramuscular replacement therapy in these patients because intramuscular doses must be limited in volume to minimize local pain and take 2 to 14 days to achieve maximal blood levels, during which time in situ degradation of up to 50% of the administered dose can occur. Five intravenous gamma-globulin preparations are currently available in the United States. The potential adverse effects of intravenous gamma-globulin infusion and the precautions currently taken to ensure safety during administration of this product are discussed.

Coxsackie B3 virus encephalitis in a patient with agammaglobulinaemia

A 19-month-old boy with agammaglobulinaemia contracted a Coxsackie B3 virus infection which caused meningoencephalitis. His neurological status deteriorated over the following 4 years and he died aged 6 years. Treatment with gammaglobulin i.m. and IgG-Fab2 fragments i.v. was not effective. Enterovirus can cause life-threatening infections in immunodeficient patients.

Role of the virology laboratory in diagnosis and management of patients with central nervous system disease

A number of viruses cause acute central nervous system disease. The two major clinical presentations are aseptic meningitis and the less common meningoencephalitis. Clinical virology laboratories are now more widely available than a decade ago; they can be operated on a modest scale and can be tailored to the needs of the patients they serve. Most laboratories can provide diagnostic information on diseases caused by enteroviruses, herpesviruses, and human immunodeficiency virus. Antiviral therapy for herpes simplex virus is now available. By providing a rapid diagnostic test or isolation of the virus or both, the virology laboratory plays a direct role in guiding antiviral therapy for patients with herpes simplex encephalitis. Although there is no specific drug available for enteroviruses, attention needs to be paid to these viruses since they are the most common cause of nonbacterial meningitis and the most common pathogens causing hospitalization for suspected sepsis in young infants in the United States during the warm months of the year. When the virology laboratory maximizes the speed of viral detection or isolation, it can make a significant impact on management of these patients. Early viral diagnosis benefits patients with enteroviral meningitis, most of whom are hospitalized and treated for bacterial sepsis or meningitis or both; these patients have the advantage of early withdrawal of antibiotics and intravenous therapy, early hospital discharge, and avoidance of the risks and costs of unnecessary tests and treatment. Enteroviral infection in young infants also is a risk factor for possible long-term sequelae. For compromised patients, the diagnostic information helps in selecting specific immunoglobulin therapy. Good communication between the physician and the laboratory will result in the most benefit to patients with central nervous system viral infection.

Failure of intraventricular gammaglobulin and alpha interferon for persistent encephalitis in congenital hypogammaglobulinaemia

A boy with congenital hypogammaglobulinaemia died at the age of 12 years after a viral meningoencephalitis of two and a half years duration due to an untypable picornavirus. He had received intravenous immunoglobulin every four weeks from the time of the start of immunoglobulin replacement treatment at the age of 3 years. The encephalitis did not respond to high dose intravenous gammaglobulin (2500 g during 22 months). The virus could not be isolated during the administration of intraventricular immunoglobulin (38.15 g) and intraventricular recombinant alpha interferon (121 X 10(6) units), but recurred rapidly each time intraventricular treatment was stopped. Further modes of treatment are still required for prevention and treatment of this disorder.

Childhood polymyositis/dermatomyositis

Children with PM/DM differ in many respects from adults with PM/DM. The most characteristic and distinctive feature is the presence of a widespread vasculopathy. Although the pathogenesis is unknown, roles for both humoral and cell-mediated immunity have been proposed. Most intriguing is the evidence for a viral agent that is capable of precipitating an ongoing, immunologically mediated reaction damaging muscles and endothelial cells. Much remains to be discovered, however, regarding the pathogenesis of this disease.

Infectious complications of the primary immunodeficiencies

The primary manifestation of the immunodeficiencies is undue susceptibility to infection. This means too many, too severe, too prolonged, too complicated and too unusual infections. Infections in immunodeficiency have a characteristic cause depending on the nature of the immune deficiency. Antibody deficiencies are associated with infections with gram-positive infections. Cellular immune deficiencies are associated with mycobacterial, protozoan, fungus, virus, and opportunistic bacterial infection. Phagocytic disorders are associated with staphylococcal, fungal, and gram-negative organisms. Complement disorders are associated by neisserial infections. Infections have also been implicated in the pathogenesis of some immunodeficiencies in some circumstances. These include human T lymphotropic virus type III (HTLV-III), rubella virus, cytomegalovirus, and Epstein-Barr virus. Several infectious syndromes in specific immunodeficiencies have been identified. Examples include enteric cytopathic human orphan (ECHO) virus encephalitis in agammaglobulinemia, and meningococcal meningitis in C6 deficiency. Infections can also be induced by live vaccines given in immunodeficiency (e.g., paralytic polio in agammaglobulinemia.) Unusual infectious syndromes will be illustrated including parainfluenza infection in severe combined and immunodeficiency, Legionella pneumonia in chronic granulomatous disease, and Cryptosporidium infection in hyper-IgM immunodeficiency.

Echovirus polymyositis in patients with hypogammaglobulinemia. Failure of high-dose intravenous gammaglobulin therapy and review of the literature

A 29-year-old man with X-linked hypogammaglobulinemia was treated with prednisone and methotrexate for polymyositis. Subsequently, it was established that disseminated echovirus 11 infection was causing the polymyositis. Treatment with large doses of intravenous gammaglobulin did not result in improvement. Viral cultures of blood, urine, and cerebrospinal fluid gave positive results throughout treatment and at postmortem examination. Multiple cultures of other tissues, including muscle, also gave positive results at postmortem examination. Severity of infection and treatment with prednisone and methotrexate prior to referral, diagnosis, and gammaglobulin treatment may explain the lack of response. A review of 23 cases of echovirus infection in patients with hypogammaglobulinemia revealed that the infection in these patients may cause meningoencephalitis or a polymyositis-like syndrome or both. Treatment with immunosuppressive agents, the standard therapy for polymyositis, is contraindicated, and intravenous or intraventricular gammaglobulin or both may be helpful.

Prolonged echoviral meningitis in a cancer patient with normal serum immunoglobulins

This is a report of prolonged meningitis caused by echovirus type 20 in a patient with rhabdomyosarcoma. It represents one of the few documented cases of delayed clearance of echovirus in the cerebrospinal fluid in a patient with normal serum immunoglobulins. The case illustrates the prolonged clinical course of echoviral meningitis in a patient receiving cytotoxic drug therapy, and it suggests that factor(s) other than humoral antibodies may be involved in the elimination of echovirus from the central nervous system.

Congenital X-linked hypogammaglobulinemia and asymptomatic hepatitis B antigen carrier state

Hepatitis occurring in patients with congenital X-linked or common variable hypogammaglobulinemia has been reported to follow a usual pattern of rapid progression from acute hepatitis to either chronic active hepatitis or death. This article describes a 21-year-old black man with congenital X-linked hypogammaglobulinemia who has been known to be a hepatitis B-associated antigen carrier during a 9-year follow up period. Liver enzyme studies are normal. His immunologic studies demonstrate no impairment of cellular immunity. His brother, who has the same disease and lives in the same household, has remained negative for hepatitis B-associated antigen. This patient demonstrates that not all hypogammaglobulinemia patients invariably have a severe clinical course with hepatitis.

Central nervous system echovirus infection in Bruton's X-linked hypogammaglobulinemia

A patient with Bruton's X-linked hypogammaglobulinemia, who developed the typical syndrome associated with systemic echovirus 3 infection whilst on routine intramuscular gammaglobulin replacement therapy, is described. Following regular infusions of specific antibody-containing plasma from his spouse, he has shown sustained clinical improvement over a period of two years, and is, therefore, one of the very rare cases with this syndrome to survive for more than a few months.

A case of agammaglobulinaemia complicated by meningoencephalitis due to Echo virus 27

A boy with agammaglobulinaemia diagnosed and treated from the age of 3 years 2 months developed encephalitis at 4 years 3 months. The illness showed a remitting but deteriorating course until death aged 6 years 5 months. Echo virus type 27 was isolated from the cerebrospinal fluid during the terminal illness. The virus was not isolated from five earlier cerebrospinal fluid samples nor was virus detected in a temporal lobe biopsy.

Immunodeficiency-disease-associated atypical chronic hepatitis: a clinicopathologic study

Chronic hepatitis occurring in patients with primary immunodeficiency disease is an uncommonly reported phenomenon. This study describes our experience with 3 patients with various immunologic abnormalities who developed chronic atypical lymphocytic infiltrates in the liver. There was a temporal relationship to Epstein-Barr virus infection in 2 cases and hepatitis A in 1. In view of the increased incidence of malignant lymphoma in several of the primary immunodeficiency states, these cases present a difficult diagnostic challenge. The recognition of the association of infiltration of the liver with small cleaved lymphocytes and a viral infection in an immunodeficient patient should alert the pathologist to the possibility that the infiltrate does not represent malignant lymphoma. These cases may be analogous to similar virus-associated lymphoproliferative disorders described in the acquired immunodeficiency of renal transplantation.

Prolonged intracerebral infection with poliovirus in asymptomatic mice

A heretofore unrecognized prolonged asymptomatic infection has been identified in mice intracerebrally inoculated with Lansing strain type II poliovirus. Virus was detected by infectivity assay and nucleic acid hybridization and was found in brains as long as 77 days after injection. Viral RNA replication occurred, indicating that persisting virus was not an inactive residuum of the infecting dose. Virus was sometimes found by infectivity even when viral RNA could not be demonstrated by hybridization, but detection by nucleic acid hybridization alone never occurred. Among 56 animals--including mice that died of infection, mice with prolonged infection, and survivors from which virus was not recovered--no animal had a serum neutralization titer above 1:2 in a plaque reduction assay Moreover, brain homogenates of 30 survivors without virus did not have neutralization titers above 1:4 in the plaque reduction assay. These findings were the same as in mock-infected mice.

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.

ECHOvirus 33 replication in human peripheral white blood cells

ECHOvirus 33 isolated from the cerebrospinal fluid of a patient with agammaglobulinemia was shown to replicate in vitro in peripheral leukocyte suspensions from a normal antibody negative donor. Replication was demonstrated by use of sequential dilution experiments. Washed glass adherent mononuclear cell cultures from a normal antibody negative donor were also capable of supporting ECHOvirus 33 replication in vitro. Leukocyte suspensions from the infected agammaglobulinemic patient extinguished detectable infectious virus in vitro.

Persistent and fatal central-nervous-system ECHOvirus infections in patients with agammaglobulinemia

We observed persistent ECHOvirus infection of the central nervous system, as defined by continued presence of isolatable virus in cerebrospinal fluid, in five patients with agammaglobulinemia. The immunologic deficit in each was characterized by absence of surface-immunoglobulin-bearing B lymphocytes and of lymph-node cortical follicles, but normal T-cell function. ECHOviruses 30, 19, 9 and 33 were recovered from cerebrospinal fluid for periods varying from two months to three years. The patients had few signs of acute central-nervous-system infection. Three of the five patients had a dermatomyositis-like syndrome, with peripheral lymphocytes that reacted with anti-human leukemia-specific primate and rabbit serums in a cytotoxicity assay. These data suggest that intact B-cell function is essential for eradication of ECHOvirus infection of the central nervous system.