A prospective evaluation of heterophile and Epstein-Barr virus-specific IgM antibody tests in clinical and subclinical infectious mononucleosis: Specificity and sensitivity of the tests and persistence of antibody.

Three heterophile antibody tests and a test specific for IgM antibody to Epstein-Barr virus were evaluated during prospective studies of infectious mononucleosis. Specificity was judged by the frequency of false-positive results in sera of known qualities taken before illness; except for two patients bled during early, unrecognized illnes,, titers of greater than or equal to 1:40 were detected in 12% by the absorbed sheep red cell test, in 6.7% by the absorbed horse red cell test, and in none by the beef cell hemolysin test. None had IgM antibody specific for Epstein-Barr virus in sera obtained before illness. In addition, no rises in titer of heterophile antibody were detected by the horse cell test in 38 patients with proved rubella and/or influenza infection. In terms of sensitivity (indicated by the percentage of cases with diagnostic titers during infectious mononucleosis), 97% were positive by the Epstein-Barr virus IgM test, 96% by the horse cell agglutination test, 85% by the beef hemolysin test, and 81% by the sheep cell agglutination test. Persistence of antibody was judged by serial bleedings up to three years after illness; titers of heterophile antibody by the sheep agglutination and beef hemolysin tests as well as titers of IgM antibody to Epstein-Barr virus returned to normal in two to three months, whereas the horse cell heterophile test remained positive for a year or more in 75%. Inapparent and mild infections with Epstein-Barr virus resulted in the production of horse cell heterophile antibody in 48.4% of 122 subjects.     

"Foreign Serum" Heterophile Antibodies in Patients Receiving Antithymocyte Antisera

Forty-six patients with venous immunologically mediated or lymphoproliferativediseases received goat antihuman thymocyte antisera globulin (ATG) therapy.Heterophile antibody production occurredin 91 % of these patients, following ATGadministration. The heterophile antibodywas absorbable with both guinea pig kidney and boiled beef erythrocyte antigens.This corresponds to a form of heterophileantibody previously reported as a "serumsickness" variety. The heterophile antibodywas composed of a mixture of gamma Gand gamma M antibodies and was partiallyabsorbed by ATG. Serum sickness did notoccur in any of these patients, in spite ofthe production of heterophile antibodies. Itis recommended that the involved heterogenetic antigen be termed "foreign serum"variety, and the resulting antibody described as a "foreign serum" type of heterophile antibody.

Submitted on January 15, 1973 Revised on March 1, 1973 Accepted on March 5, 1973     

Immunochemical Studies of Infectious Mononucleosis

Abstract. The major sialoglycopeptide released from bovine erythrocytes by papain has been purified and characterized. The glycopeptide contains 82% by weight carbohydrate in molar ratios of galactose -5. 5 :N-acetylglucosamine -3. 6 :sialic acid -2. 6 :N-acetylgalactosamine -1.0. The carbohydrate and amino acid composition is quite different from the glycoprotein extracted from bovine erythrocyte stroma with hot 75% ethanol. The glycopeptide is devoid of reactivity with Paul-Bunnell heterophile antibody of infectious mononucleosis - an activity expressed to high degree on the bovine erythrocyte and associated with glycoprotein. The glycopeptide does react, however, with another antibody found in infectious mononucleosis as well as most normal human sera tested.     

Autohemagglutinins and hemolysins with hemoglobinuria and acute hemolytic anemia,in an illness resembling infectious mononucleosis

A case is reported of a young man with acute hemolytic anemia and hemoglobinuria who presented: an initial blood picture consistent with infectious mononucleosis, associated with a heterophile agglutination test positive in high dilution;auto-hemagglutinins, active in the cold, at room temperature and at 37 Centigrade;a hemolysin active at 37 C. after chilling, requiring the presence of a thermolabilecomponent of serum for hemolysis; a positive Donath-Landsteiner test but no evidence of syphilis. In addition there was clubbing of the digits with certain otherroentgenologic changes in the bones; absence of any other etiologic factors knownto be concerned with such anemia; uneventful improvement under massive transfusion therapy, with apparent recovery from his hematologic disorder whenstudied two years later.

Note: ACKNOWLEDGMENTOur thanks are due to Dr. Maxwell Finland and Dr. Philip F. Wagley for suggestions in preparingthis report. We are especially indebted to Dr. T. Hale Ham for his patient and critical advice and encouragement.

     

Heterophile Antibodies in the Serum of Children with Nephrotic Syndrome1

Serum of children with the nephrotic syndrome contained high titers of a (19s) IgM antibody against sheep, horse, guinea pig, rat, and rabbit red blood cells but not against cow red blood cells. There was high correlation between high titers of antisheep antibodies and active nephrotic syndrome in the children with minimal change nephrotic syndrome. The antibody differed from the Paul-Bunnell antibody found in patients with infectious mononucleosis and from the anti-Forssman, Hangautziu-Deicher antibody found in patients with horse serum sickness. Rabbit red blood cells completely absorbed the antibody, but horse or guinea pig red blood cells removed only the anti-Forssman activity.     

19S IgM forssman-type heterophhile antibodies in juvenile rheumatoid arthritis

Fifty-four sera from children with juvenile rheumatoid arthritis (JRA) were separated by gel filtration at pH 4.05. The serum and IgM and IgG-containing fractions were analyzed for heterophile antibodies by subjecting them to a hemolytic assay in tubes with the target cell a 1% washed sheep erythrocyte (SRBC) or beef erythrocyte (BRBC) in suspension. Thirty-three of 54 sera showed hemolytic antibody titers >1:640 against SRBC alone and 4 of 54 had titers >1:320 against SRBC and BRBC. All positive titers against SRBC and BRBC were associated with the IgM fraction. Differential absorption with SRBC, BRBC, and tissue sediment of homogenized guinea pig kidney revealed a Forssman specificity in 33 sera and Forssman and Hanganutziu-Deicher specificity in 4. The presence of heterophile antibodies in JRA correlated with the presence of hidden rheumatoid factor. There was also an increased incidence in patients with positive antinuclear antibodies and in teenaged females with polyarticular disease.     

Positive Epstein-Barr virus heterophile antibody tests in patients with primary human immunodeficiency virus infection

PURPOSE: To describe three cases of primary human immunodeficiency virus (HIV) infection in patients who had laboratory studies consistent with infectious mononucleosis. SUBJECTS: We describe 3 patients who presented with a viral syndrome, had a positive heterophile antibody test, and were diagnosed with primary HIV infection. RESULTS: The results of Epstein-Barr virus serology studies in each of these patients were consistent with chronic, but not acute, Epstein-Barr virus infection. HIV antibody tests were negative, and HIV RNA was >500,000 copies/mL in each patient. CONCLUSIONS: Clinicians should recognize that a positive heterophile antibody test in the setting of an acute viral illness does not exclude the diagnosis of primary HIV infection, although reactivation of latent Epstein-Barr virus infection cannot be ruled out. Patients presenting with nonspecific viral syndromes should be assessed for HIV risk behaviors and tested for primary HIV infection when appropriate.     

Successful plasmapheresis in corticosteroid-resistant hemolysis in infectious mononucleosis: role of autoantibodies against triosephosphate isomerase.

A 19-year-old girl fell ill with a high temperature and cervical lymphadenopathy. The detection of heterophile antibodies as well as Epstein-Barr-virus-specific antibodies confirmed the diagnosis of infectious mononucleosis. In the course of the infection, the patient developed severe hemolytic anemia with her hemoglobin falling from 14 to 8 g/dl. High-dose corticosteroid therapy did not stop hemolysis; this could only be achieved by seven plasmapheresis sessions. Antibodies against triosephosphate isomerase (TPI) and the blood group marker 'i' were found in the patient's serum. Anti-i cold agglutinins were not active at 37 degrees C, whereas antibodies against TPI caused increased 51Cr release from marked patient's erythrocytes in vitro. Plasmapheresis removed the autoantibodies effectively and stopped the hemolysis. After 8 weeks, the patient gradually recovered.     

Studies on heterophile antibodies in rheumatoid arthritis

Sera and synovial fluids of patients with rheumatoid arthritis were studied for the presence of heterophile antibodies to sheep and bovine erythrocytes by means of hemolysis in agar gel. It was demonstrated that 18 of 146 sera had hemolytic antibody titers of 160 or more; all 18 (12%) against sheep and 8 (6%) against bovine erythrocytes. Of 31 synovial fluids examined, 5 showed hemolysin titers of 40 or more; all 5 (16%) against sheep and 3 (10%) against bovine erythrocytes. These heterophile antibodies were shown to belong to IgM and/or IgG class. Absorption and inhibition studies revealed that antibodies of 10 positive sera and 2 synovial fluids were of Forssman specificity and antibodies of 6 sera and 3 synovial fluids were of Hanganutziu-Deicher specificity. Two remaining sera were shown to contain a mixture of Forssman antibodies and immune anti-B antibodies.     

Hepatitis in fatal infectious mononucleosis

A detailed clinicopathologic analysis of 30 patients with sporadic fatal infectious mononucleosis and 31 males with fatal infectious mononucleosis and the X-linked lymphoproliferative syndrome was performed to determine the extent of hepatic dysfunction in these cases. At death, the median age of patients with sporadic infectious mononucleosis was 10.7 yr vs. 2.4 yr for X-linked lymphoproliferative syndrome. The median survival time was 8 wk for sporadic infectious mononucleosis and only 4 wk for X-linked lymphoproliferative syndrome. The male to female ratio was 3:2 in sporadic infectious mononucleosis; all patients with X-linked lymphoproliferative syndrome were males. Fever, sore throat, lymphadenopathy, hepatomegaly, and splenomegaly were prominent findings. Hepatic dysfunction was uniformly present and caused death in 13 of 30 sporadic infectious mononucleosis cases and 18 of 31 X-linked lymphoproliferative syndrome cases. Diagnosis of infectious mononucleosis was confirmed by heterophile antibody titers or Monospot, Epstein-Barr virus antibody studies, viral culture, molecular hybridization studies, clinical and histologic findings, and pedigree analysis.     

The rapid serological diagnosis of infectious mononucleosis.

A total of 121 samples of serum collected from 101 patients was tested to determine the sensitivity and specificity of a commercial latex agglutination test for detecting infectious mononucleosis heterophile antibody, a commercial immunofluorescence test for detecting antibody to Epstein-Barr virus capsid antigen and a rapid enzyme immunoassay for detecting antibody to Epstein-Barr virus nuclear antigen. Although the Epstein-Barr virus capsid antigen IgM indirect immunofluorescence test proved to be the most sensitive, false-positive reactions were seen when samples collected from patients with cytomegalovirus, hepatitis A virus, parvovirus and leptospira infection were tested. False-positive reactions were also seen with samples containing rheumatoid factor.     

Positive serological tests for infectious mononucleosis in a patient with mediterranean spotted fever

The Monospot test is an accurate and reliable test for infectious mononucleosis. False positive reactions have been seldom recorded. We report the conversion of the Monospot test from negative to positive during the course of Mediterranean spotted fever. Changes in the titre of the Paul-Bunnell test were observed also. The importance of measuring IgM antibodies as part of the routine investigation of infectious diseases is emphasised.     

The absence of the heterophile reaction in the spinal fluid in infectious mononucleosis

The spinal fluid was studied in twenty cases of infectious mononucleosis provedby clinical picture, blood studies and serological examination. It may be concluded that in acute cases of infectious mononucleosis, the heterophile antibodydoes not pass into the spinal fluid, but that there may be an increase in cell count,particularly lymphocytes, and in protein content, which is not necessarily proportional to the cell count elevation. These findings have no correlation withcentral nervous system signs or symptoms.

     

Virologic diagnosis,viral monitoring,and treatment of epstein-barr virus infectious mononucleosis

Epstein-Barr virus (EBV) is the cause of infectious mononucleosis and is associated with severe infections in immunocompromised patients. EBV is also causally linked with several human malignancies. The heterophile antibody test and EBV-specific antibody tests remain the principal means of diagnosis of initial infection in otherwise healthy patients. Enzyme-linked immunosorbent assays have replaced the traditional immunofluorescence assays for EBV-specific antibodies. Several newer molecular diagnostic tests have become available that facilitate accurate monitoring of infection. The role of these tests for patients with uncomplicated infectious mononucleosis is limited, although these tests are being increasingly used to monitor the state and level of EBV replication for severe infections and among immunocompromised patients. Antiviral therapy has a limited, short-term effect on oropharyngeal shedding but has proven ineffective for the clinical manifestations of infectious mononucleosis. Patients with selected complications frequently benefit from short-term corticosteroid therapy.     

Hematologic differences in heterophile-positive and heterophile-negative infectious mononucleosis

Infectious mononucleosis (IM) due to all causes is characterized by atypical lymphocytosis. We sought to compare hematologic parameters of infectious mononucleosis due to Epstein-Barr virus (EBV) infection (heterophile antibody (HA) positive) with mononucleosis due to other causes. Mono-Latex Slide Agglutination Test results and complete blood counts (CBC) of 147 patients with mononucleosis were retrospectively analyzed. Leukocyte count, absolute lymphocyte count, and presence of atypical lymphocytes in EBV-positive and EBV-negative groups were statistically compared. We analyzed 68 EBV-positive and 79 EBV-negative cases. EBV-positive patients were significantly younger than EBV-negative patients were. Mean total WBC count and mean absolute lymphocyte count were significantly higher in EBV-positive patients. Absolute lymphocytosis, absolute leukocytosis, and atypical lymphocytosis were also significantly more frequent in EBV-positive patients. Leukopenia was more frequently seen in EBV-negative patients.     

Reappraisal of the Role of Anti-i in Haemolytic Anaemia in Infectious Mononucleosis

S ummary . Current literature implies that haemolytic anaemia in infectious mononucleosis is regularly caused by the temporary production of high thermal amplitude cold agglutinins of anti-i specificity. More recently, Capra et al (1969) suggested interaction between IgG anti-i and anti-IgG antibodies as the cause of haemolytic anaemia in infectious mononucleosis. A detailed serologic evaluation of three patients during moderate to severe haemolytic anaemia in infectious mononucleosis revealed high thermal amplitude anti-i in only one. This patient's direct antiglobulin test (DAT) was negative using anti-IgG but was 3 + using anti-C₃ and -C₄. The serum antibody titre against cord or adult Oi cells was 512 at 4°C and 4 at 31°C. The anti-i was inhibited by mercaptoethanol, and anti-IgG was not found in the patient's serum. Patient 2 had a negative DAT and patient 3 had a 2 + DAT using anti-C₃ and anti-C₄. Anti-i was present only in low titre at 4°C and was unreactive at 20°C. It was inhibited by mercaptoethanol. These patients' sera contained anti-IgG antibodies. In none of our patients were warm autoantibodies detected. This data demonstrates that haemolytic anaemia in infectious mononucleosis is not necessarily associated with high thermal amplitude anti-i. Further, since the anti-i antibodies in patients 2 and 3 were of low titre, were inhibited by mercaptoethanol, and did not react at physiologic temperatures, the mechanism of haemolysis in these patients does not seem related to the interaction of anti-IgG and IgG anti-i antibodies. Further work is necessary to clarify the mechanism of haemolytic anaemia in infectious mononucleosis.     

Severe Haemolytic Anaemia Complicating Infectious Mononucleosis

Summary: Severe haemolytic anaemia complicating infectious mononucleosis. R. K, Woodruff and A. J. McPherson, Aust. N.Z, J. Med., 1976, 6, pp. 569–570.
The case record of a patient suffering from infectious mononucleosis, complicated by severe haemolytic anaemia with overt intravascular haemolysis, is reported. Investigation of such cases usually shows a high titre of cold agglutinins with anti-i specificity. In the case reported, the results of serological investigations were atypical, and suggested that cold agglutinins with anti-l activity (rather than anti-i) were predominant in the aetiology of the haemolysis.     

Cold agglutinins in infectious mononucleosis and heterophil-antibody-negative mononucleosis-like syndromes.

Cold agglutinins (CA) were evaluated prospectively in patients with various mononucleosis syndromes and in a large control group. Cold agglutinins with anti-i specificity were seen mainly in heterophil-positive or -negative Epstein-Barr virus (EBV)-induced infectious mononucleosis (31.8% of cases). Unclassified CA with equal reactivity against cord and adult erythrocytes were seen in 56 of 150 (37.3%) cases of heterophil-antibody-positive infectious mononucleosis (IM), in 1 of 7 (14.3%) cases of heterophil-negative EBV-induced IM, and in 12 of 31 (38.7%) cases of the heterophil-negative mononucleosis-like syndrome due to cytomegalovirus or other unspecified agents. One patient with heterophil-positive IM had a persistent, partially papain sensitive CA with anti-Pr-like activity. Anti-i CA were seen in less than 1.0% of healthy young adults (500) or patients without mononucleosis (500) submitted for heterophil studies. Unclassified CA were noted in 3.2% of the latter 1000 samples.     

Diagnostic evaluation of mononucleosis-like illnesses

Clinicians face a diagnostic challenge when a patient with the classic fever, pharyngitis, and lymphadenopathy triad of infectious mononucleosis has a negative “spot” heterophile antibody test. This screening test, although commonly considered sensitive for the presence of Epstein-Barr virus (EBV) infection, may be negative early after infection. A growing number of pathogens have been reported to cause heterophile-negative mononucleosis-like illnesses, including cytomegalovirus (CMV), human herpesvirus 6 (HHV-6), human immunodeficiency virus (HIV), adenovirus, herpes simplex virus (HSV), Streptococcus pyogenes, and Toxoplasma gondii. Other infectious and noninfectious disorders also may present in ways that mimic mononucleosis, but fail to generate EBV’s archetypal triad of clinical findings. A systematic approach to the diagnosis of mononucleosis-like illnesses ensures that conditions warranting specific therapy are distinguished from others requiring only supportive care.     

Fine Structure of Leukocytes in Infectious Mononucleosis: In Vivo and In Vitro Studies

The peripheral blood mononuclear cell population in patients with heterophile positive infectious mononucleosis is comprised of small and mediumsized lymphocytes, monocytes, increased numbers of lymphoid-plasma (LP)cells, and large lymphocytoid cells with abundant polysomes. Cell-lines derived from these patients contain a spectrum of cells of the lymphoid plasmacell series. These cultures are morphologically indistinguishable from Burkittlymphoma and leukemic suspension cultures. A large portion of the cellspresent in these continuous suspension cultures have fine structural featuressimilar to phytomitogen stimulated lymphocytes, and to cells implicated inthe immune response.

Submitted on November 26, 1968 Accepted on February 26, 1969