Evaluation of T cell subsets by an immunocytochemical method compared to flow cytometry in four countries

The authors tested an alternative method for CD4 and CD8 T lymphocytes enumeration, the immunoalkaline phosphatase method (IA), in three African countries and in Denmark. The IA determinations from 136 HIV antibody positive and 105 HIV antibody negative individuals were compared to the corresponding results obtained by flow cytometry (FC) performed in the respective countries. The authors found good correspondence between the two methods for measurements of CD4 and CD8 T lymphocytes independent of serological status and geographical site. However, the CD4 and CD8 T lymphocytes values obtained by the two methods are not interchangeable as IA compared to FC consistently gives higher percentage of CD4 T lymphocytes, and lower percentage of CD8 T lymphocytes. Mean differences between the two methods did not differ between the three African countries indicating that the IA method provides systematic results. Replicate measurements suggested good correspondence between results obtained by IA. By using an IA level of < 300 CD4 T lymphocytes/microliter, the sensitivity was 81% and specificity 96% for detecting an FC level of < 200 CD4 T lymphocytes/microliter. Using an IA level of < 20% CD4 T lymphocytes, the sensitivity was 89% and specificity 95% for detecting an FC level of < 14% CD4 T lymphocytes. The FC and IA methods had the same internal correspondence between low absolute CD4 T cell count and low CD4 percentages; the sensitivity and specificity for detecting a low absolute CD4 T cell counts with a low CD4 percentage was 92% and 68% for FC and 91% and 73% for IA, respectively. The IA method is 10-fold cheaper than FC, is independent of advanced laboratory facilities, and does not need immediate processing of samples as blood smears can be stored for long periods. The IA method is therefore suitable for use in areas with limited resources and laboratory facilities where there is a need for immunological surveillance in hospital or community studies.

Retention of the antibiotic teicoplanin on a hydromer-coated central venous catheter to prevent bacterial colonization in postoperative surgical patients

OBJECTIVE

Antibiotic-coated intravascular catheters may be an effective means of decreasing bacterial colonization and subsequent catheter-related infection. The present study was designed to investigate the retention of the antibiotic teicoplanin on a hydromer-coated intravenous catheter and the effect of this antibiotic coating on catheter bacterial colonization.

DESIGN

A prospective, randomized pilot study.

SETTING

Operating rooms (ORs) and an intensive care unit (ICU) at a university hospital.

PATIENTS

A consecutive group of 20 male patients undergoing major abdominal surgery.

INTERVENTIONS

Control (C; n = 10) or teicoplanin-coated (T; n = 10) single-lumen central venous catheters were inserted before surgery in the OR. Catheters were withdrawn at the discretion of the physicians in the ICU after various periods.

MEASUREMENTS

The teicoplanin content of the catheter material was assessed using a bioassay with Bacillus subtilis after complete elution of the antibiotic from the catheter. Bacterial colonization was measured using a quantitative culture technique after the catheter lumen had been flushed and the catheter segments sonicated.

MAIN RESULTS

Nearly three-quarters of the initial teicoplanin coating (374 +/- 103 micrograms; mean +/- SD) were released during the first day of catheterization, and after 36 h of intravenous catheterization, no antibiotic was retained on the catheter. No significant difference could be found either in the incidence of bacterial colonization between test (n = 3) and control (n = 4) catheters or in the number of colony-forming units (CFU) on the catheter segments (T, 263 +/- 104 CFU/cm; C, 372 +/- 294 CFU/cm; mean +/- SEM).

CONCLUSION

The retention of teicoplanin antibiotic coating on hydromer catheters is only short term if catheters are inserted intravenously. This may limit clinical antibacterial efficacy.

Retention of antibacterial activity and bacterial colonization of antiseptic-bonded central venous catheters

We determined how long antiseptic impregnation with silver sulphadiazine and chlorhexidine (SCC) on polyurethane central venous double- or triple-lumen catheters is retained in vivo. A total of 116 antiseptic catheters were tested for antibacterial activity in an in-vitro bioassay after various periods of iv catheterization. Segments from the subcutaneous (sc) and intravenous (iv) portions of the catheters were cultured. The results of test antiseptic catheters were compared with those from 117 noncoated control (c) catheters. Retention of antibacterial activity followed an exponential curve and lasted for up to 520 h after catheter insertion. Significant differences (P = 0.0001) between SSC and C catheters were noticed with regard to the quantitative level of bacterial colonization (SSC-sc 87 +/- 34 vs C-sc 584 +/- 122; SSC-iv 52 +/- 17 vs C-iv 286 +/- 57; all values are given as mean cfu +/- S.E.M.), and the frequency of bacterial colonization (SSC-sc 20.7% vs C-sc 38.5%, P = 0.0047; SSC-iv 18.1% vs C-iv 30.8%, P = 0.0361). There was no significant difference between the incidence of catheter-related bacteraemia in the test (n = 0) and control groups (n = 3) (P = 0.2573). Further prospective studies are required to delineate the role of antiseptic catheters in preventing catheter-related infections.

Determination of CD4+ and CD8+ lymphocytes with the cytosphere assay: a comparative study with flow cytometry and the immunoalkaline phosphatase method

The proportion and absolute numbers of CD4+ and CD8+ lymphocytes in peripheral blood were determined using a new manual method, the cytosphere assay (CA). This method uses small latex beads coated with monoclonal antibodies directed against the CD4 and CD8 receptors, respectively. The CA was compared with two other methods for determination of T lymphocyte subsets, flow cytometry (FC) and the immunoalkaline phosphatase (IA) method, by testing HIV-seropositive and HIV-seronegative samples from Denmark (44) and Ivory Coast (79). For HIV-seropositive samples, both the proportion and the absolute number of CD4+ lymphocytes determined by CA showed a good correlation with results obtained by FC (correlation coefficients were 0.92 and 0.74 in Denmark and The Ivory Coast, respectively) and IA (correlation coefficients were 0.94 and 0.66 in Denmark and The Ivory Coast, respectively). However, for HIV-seronegative samples the corresponding correlation coefficients were low. CD4% determinations deviated more from FC counts at higher CD4 counts than at lower levels for both seronegative and seropositive individuals. In conclusion, the CA performed best for samples from HIV-infected individuals. Before a more general utilization of the method, it is necessary to improve its repeatability and standardize its performance at all levels of CD4+ T cells.

HIV-1 and HIV-2 antibodies in pregnant women in the City of Maputo, Mozambique. A comparative study between 1982/1983 and 1990

The seroprevalence of HIV-1 and HIV-2 among pregnant women in Maputo, the capital of Mozambique, was compared between the years 1982/83, 1988 and 1990. None of the 432 serum samples collected in 1982/83 was positive for HIV antibodies whereas in 1988 the HIV-1 and HIV-2 seroprevalence was 0.4% (2/500) and 0.6% (3/500), respectively, and in 1990 0.6% (12/2014) and 0.2% (4/2014), respectively. These results indicate that HIV infection has been introduced recently in Maputo and is spreading at a slow rate among women.

Comparison of linear antigenic sites in the envelope proteins of human immunodeficiency virus (HIV) type 2 and type 1

The occurrence of dominant linear antigenic sites in the envelope glycoproteins of human immunodeficiency virus type 2 (HIV-2) was evaluated. Twenty-five peptides representing different regions of HIV-2, strain SBL-6669, were synthesized. For comparison the corresponding peptides of HIV-1, strain BRU, were also prepared. The peptides were tested in enzyme-linked immunosorbent assay (ELISA) with human sera from individuals with proven HIV-1 or HIV-2 infection and simian sera from animals infected with HIV-2 or simian immunodeficiency virus of sooty mangabay monkey origin (SIVsm). Four major antigenic regions were identified. Peptides representing parts or the whole V3 (neutralizing loop) region and an additional stretch of amino acids located at the carboxy terminal of this region showed considerable reactivity. This reaction was predominantly type specific, but some heterotypic reactivity was also seen. Peptides representing the carboxy terminal 21 amino acids of the V3 region of the type-related viruses HIV-2 and SIVsm allowed selective identification of strain-specific antibodies. A second major antigenic region was found close to the carboxy terminal end of the large glycoproteins. This region was cross-reactive between the two types. The two additional dominating antigenic regions were located in the amino terminal region of the transmembrane glycoprotein. One region has previously been shown to be a uniquely antigenic type-specific site. The other region was also type-specific, but was identified only in HIV-2, amino acids Glu634-Lys649. Excellent facilities are available for the design of not only type-unique site-specific serological tests but potentially also type-cross-reactive and strain-specific assays.

A prospective study of 115 initially asymptomatic HIV infected gay men in Stockholm, Sweden

A cohort of 115 asymptomatic gay men, all seropositive for HIV, was recruited in a health screening project in Stockholm, Sweden, between Nov. 1982 and Dec. 1983 and subsequently followed and clinically evaluated after a mean observation time of 63 months. AIDS in accordance with the surveillance definition (CDC group IV C-1 and D) developed in 34 (29.6%) of the men, while 1 (0.9%) additional man died of multiple myeloma classified as CDC group IV E. Constitutional symptoms (CDC group IV A) developed in 13 (11.3%) men, while symptoms from the central nervous system classified as CDC group IV B occurred in 1 (0.9%) additional man. Minor opportunistic infections included in the definition for CDC group IV C-2 developed in 12 (10.4%) men, while 48 (41.7%) men remained asymptomatic, with or without persistent generalized lymphadenopathy (PGL). One man who died of AIDS had been treated for malignant melanoma (MM) and one who did not fulfill the criteria for CDC group IV died of MM during the observation period. The 5-year actuarial progression rate to surveillance defined AIDS was 31.5% and to CDC group IV 53.6%. No statistically significant association was found between disease progression and a number of recorded epidemiological variables, most previous and present sexually transmitted diseases (STD) (except gonorrhoea) and the presence of PGL at entry. On the other hand, reduced delayed cutaneous hypersensitivity, in particular to tuberculin, as well as the presence of a high IgG titer against cytomegalovirus (CMV), were correlated to disease progression.

Clinical signs and laboratory markers in predicting progression to AIDS in HIV-1 infected patients

In a prospective longitudinal study 89 men with HIV-1 infection were observed for a mean time of 51 months with regard to clinical signs and laboratory findings predictive of progression to AIDS/opportunistic infection (OI). In a bivariate regression analysis the clinical signs showing a significant relation to AIDS development were: dermatitis of the face, yellow toe nail changes, hairly leukoplakia and oral candidiasis. The laboratory findings significantly associated with progression to AIDS were: decrease of the relative and absolute number of CD4 lymphocytes, decrease of the CD4/CD8 ratio, HIV p24 antigenaemia, lack of anti-HIV p24, elevated erythrocyte sedimentation rate, anaemia and elevated serum-beta-2-microglobulin. The relative number (%) of CD4 cells was found superior to the absolute number and the CD4/CD8 ratio. In a multivariate regression analysis decrease of CD4 lymphocytes and lack of anti-HIV p24 were independently associated with subsequent AIDS/OI development.

Immunological changes in primary HIV-1 infection

Homosexual men with symptomatic primary HIV-1 infection displayed a pronounced lymphopaenia with significantly depressed numbers of CD3+, CD4+ and CD8+ cells and B cells during the first week of illness. Subsequently, the CD8+ cell counts rose in parallel with numbers of CD3+ cells, atypical lymphocytes and activated (CD38+ and HLA-Dr+) cells to attain maximal levels about a month following onset of illness. In contrast CD4+ and B cell numbers remained low for an extended period of time. Early signs of a host response included a transient appearance of interferon-alpha in the blood and raised levels of neopterin and beta 2-microglobulin (beta 2-M). Neither CD4+/CD8+ cell ratio nor beta 2-M resumed completely normal values during a follow-up period of 2 years. These findings shed some light on pathogenetic events during early HIV-1 infection and suggest that the infection, following the acute symptomatic stage, usually enters a stage of chronic active rather than latent infection.

Envelope cross-reactivity between human immunodeficiency virus types 1 and 2 detected by different serological methods: correlation between cross-neutralization and reactivity against the main neutralizing site

A total of 70 human immunodeficiency virus type 1 (HIV-1) and 42 HIV-2 antibody-positive serum samples, collected from groups of individuals in which only one type of HIV prevails, were tested for cross-reactivity against HIV-2 and HIV-1 proteins by Western blot (WB) (immunoblot), radioimmunoprecipitation assay (RIPA), neutralization analysis, and enzyme-linked immunosorbent assay with as antigen synthetic peptides representing selected parts of the envelope (env) glycoproteins. Cross-reactions against the env glycoproteins were observed by WB in 10% (7 of 70) and by RIPA in 40% (28 of 70) of the HIV-1 antibody-positive serum samples and by WB in 29% (12 of 42) and by RIPA in 48% (20 of 42) of the HIV-2 antibody-positive serum samples. Testing by enzyme-linked immunosorbent assay against a 36-amino-acid peptide (Cys-301-Cys-336) of the external glycoprotein of strain HTLV-IIIB of HIV-1 (HIV-1HTLV-IIIB) (known to represent a dominating, linear neutralizing site) showed type-specific reactions in 67% (38 of 57) of HIV-1 antibody-positive serum samples. Type-specific reactions against a homologous 35-amino-acid peptide of strain SBL-6669 of HIV-2 (HIV-2SBL-6669) were found in 75% (30 of 40) of HIV-2 antibody-positive serum samples, and these reactions were correlated to neutralization against HIV-2SBL-6669. Cross-reactions against these peptides were seen in 23% (13 of 57) and 33% (13 of 40) of the HIV-1 and HIV-2 antibody-positive serum samples, respectively. These cross-reactions were correlated to cross-neutralization against HIV-1HTLV-IIIB and HIV-2SBL-6669. Cross-neutralization against one heterotypic virus strain was demonstrated in 16% (9 of 57) of HIV-1 antibody-positive serum samples and in 22% (5 of 22) of HIV-2 antibody-positive serum samples, but no correlation was found between cross-neutralization and env cross-reactivity in WB or RIPA.

Replicative capacity of HIV-2, like HIV-1, correlates with severity of immunodeficiency

We have obtained 15 HIV-2 isolates from the peripheral blood mononuclear cells (PBMCs) of 24 HIV-2-infected west African people. The frequency of virus isolation correlated with the severity of HIV-2 infection; only three isolates were obtained from 11 asymptomatic individuals, whereas virus was isolated from nearly all (12 of 13) individuals with symptoms. The HIV-2 isolates showed distinct replicative and cytopathic characteristics and, similarly to HIV-1 isolates, could be divided into two major groups: rapid/high and slow/low. Rapid/high isolates, i.e. isolates with the ability to replicate in tumour cell lines, were obtained from individuals with symptomatic HIV-2 infection and CD4+ lymphocyte counts less than 360/microliters blood; these isolates induced syncytia in PBMC cultures. HIV-2 isolates unable to replicate continuously in tumour cell lines (slow/low isolates) induced small syncytia, cell death, or no cytopathic effect at all. All HIV-2 isolates obtained from asymptomatic individuals showed a slow/low replication pattern.

Cross-neutralizing antibodies against HIV-1 (HTLV-IIIB and HTLV-IIIRF) and HIV-2 (SBL-6669 and a new isolate SBL-K135)

A total of 57 HIV-1 antibody-positive sera and 43 HIV-2 antibody-positive sera were all tested for neutralizing capacity against two HIV-1 isolates (HTLV-IIIB and HTLV-IIIRF) and two HIV-2 isolates (SBL-6669 and SBL-K135). SBL-K135 is a new HIV-2 isolate obtained from a patient with clinical AIDS from Guinea-Bissau. Among the HIV-1--positive sera, 84% neutralized any of the HIV-1 isolates, 67% neutralized both HIV-1 isolates, and 35% neutralized any of the HIV-2 isolates. Among the HIV-2--positive sera, 91% neutralized any of the HIV-2 isolates, 67% neutralized both HIV-2 isolates, and 37% neutralized any of the HIV-1 isolates. Thus, neutralizing antibodies in HIV-1-- and HIV-2--positive sera can be cross-reacting, type-specific, or strain-specific. The cross-neutralizing titers were lower than the neutralizing titers against the type-specific viral isolates. The presence of cross-neutralizing antibodies was related to the presence of neutralizing antibodies against both type-specific isolates.

Natural history of HIV infection in Swedish haemophiliacs

The longitudinal follow-up is described of 36 anti-HIV positive haemophiliacs who had seroconverted in the period 1980-82, and of 41 seronegative controls. Laboratory variables were followed up for a mean duration of 2.5 years (1985-87). Of the 36 seropositive patients, AIDS developed in 3, and generalised persistent lymphadenopathy in 9. The HIV-seropositive patient group had lower CD4:CD8 ratios and CD4 counts but higher CD8 counts than the seronegative group. However, there was no deterioration in the values for the lymphocyte subsets during follow-up. Titration on paired sera showed an increase in anti-HIV titre with time. Testing for the presence of HIV antigen was positive in 5 patients, including 2 who later developed AIDS. We conclude that anti-HIV positive haemophiliacs, though actively immunised, often show no symptoms even as long as 7 yr after seroconversion and that, in certain patients, the immune system may even show signs of improvement.

Follicular involution in HIV lymphadenopathy. A morphometric study

Lymph node biopsies from 75 HIV infected patients (71 homo- and bisexual men, 3 hemophiliacs and 1 woman) were studied using immunohistochemical methods with monoclonal antibodies (Mabs) against B lymphocytes, subsets of T lymphocytes, follicular dendritic cells (FDC) and HIV gag proteins p24 and p18. Histopathological changes were classified as follicular hyperplasia (FH), fragmentation (FF), atrophy (FA) and depletion (FD). Immunohistochemical stainings were quantified with the help of an Image Quantifier (IQ) and the reactivity for respective Mab-defined antigen was related quantitatively to other antigens and histopathological changes. Such measurements showed an increase in FDC in biopsies with FH and FF histology and a decrease in FA and FD cases in comparison with cases with non-HIV related lymphadenopathy. In addition it was found that the decrease in FDC was correlated with an increase in CD8+ within the follicles. Double immunostainings for p24 and various cellular markers showed that p24 was predominantly associated with follicular dendritic cells. Essentially the same findings were observed in the lymph nodes irrespective of risk group. Possible mechanisms involved in follicular involution in HIV-related lymphadenopathy are discussed.

Predictive markers of AIDS: a follow-up of lymphocyte subsets and HIV serology in a cohort of patients with lymphadenopathy

From 1982 to 1985, 89 HIV-1 seropositive men with persistent generalized lymphadenopathy (PGL) were enrolled into a prospective longitudinal study. In February 1988, after a mean observation time of 45 months, 23 patients had progressed to AIDS with opportunistic infection (AIDS/OI), 4 had developed Kaposi's sarcoma, 47 had developed HIV-related symptoms, 14 still had PGL as only symptom, and 1 was lost to follow-up. Patients with CD4 lymphocytes less than or equal to 0.40 x 10(9)/l as well as patients with HIV antigenaemia and those lacking antibodies to p24 all had a significantly higher risk of developing AIDS/OI within 30 months of observation than other patients. HIV antigen was present in 70% and antibodies to p24 were lacking in 61% of the patients at the time of AIDS/OI diagnosis. All but one (96%) of the AIDS/OI patients had CD4 numbers less than or equal to 0.20 x 10(9)/l at the same time. The estimated median time to AIDS/OI in patients with HIV antigenaemia was 21 months and in patients lacking p24 antibodies 27 months. In patients with CD4 numbers less than or equal to 0.20 and 0.40 x 10(9) cells/l the estimated median time to AIDS/OI was 14 months and longer than 30 months, respectively.

HIV-serology and lymphocyte subsets in relation to therapy and clinical development in haemophiliacs

389 Swedish patients with haemophilia A, B or von Willebrand's disease were examined for HIV-1 antibodies. T-cell subsets were measured in 260 of them. HIV-1 antibodies were found in 98 of these patients. Of the 199 patients with severe or moderate haemophilia A, 44% were seropositive. They had seroconverted between 1979 and 1983. HIV-1-seropositive patients had significantly decreased numbers of CD4 cells and increased numbers of CD8 cells. The seronegative haemophilia A patients had significantly increased numbers of CD8 cells. The T-cell subsets were followed for a median of 40 months in 73 seropositive patients. All groups of patients, at different clinical stages, showed decreasing numbers of CD4 cells. The most pronounced decrease was seen in the patients who developed AIDS, followed by the group which developed HIV-related signs or symptoms. HIV antigen in serum and antibody pattern in Western blot and ELISA were followed in 89 patients. HIV-1 antigen was present and p24 antibodies were lacking in 11% and 13% of asymptomatic subjects, in 13% and 20% of patients with persistent generalized lymphadenopathy, in 33% and 38% of patients with other HIV-related signs or symptoms and in 5/6 of the AIDS patients, respectively. In conclusion, the decrease of CD4 cells and the presence of HIV antigen and/or absence of p24 antibodies were found to be prognostic markers for HIV disease.

Neutralizing antibodies in relation to antibody-dependent cellular cytotoxicity-inducing antibodies against human immunodeficiency virus type I

The presence of neutralizing antibodies against human immunodeficiency virus type 1 (HIV-1) was investigated in sera from 73 HIV-1 seropositive subjects at different clinical stages. Virus neutralization was measured as survival of MT-4 cells in a 6-7 day microassay. Sixty-three sera were also tested for antibodies inducing virus-specific antibody-dependent cellular cytotoxicity (ADCC). Neutralizing antibodies were found in 59% of sera tested, the positivity rate being 50% (9/17) in asymptomatic subjects, 67% (12/18) in patients with persistent generalized lymphadenopathy (PGL) and 54% (14/26) in AIDS patients (not significant differences). ADCC antibodies were present in 43% of the sera. Neutralizing antibodies and ADCC-inducing antibodies were found simultaneously in 35% (22/63) of the sera. Neutralizing antibodies alone were found in 22% (14/63) and ADCC antibodies alone in 6% (4/63) of the sera tested. Thirty-seven per cent (23/63) of the sera were negative for both types of antibodies, 62% of the sera with neutralizing antibodies also had ADCC inducing antibodies and 85% of the sera with ADCC antibodies had neutralizing antibodies. The titres of ADCC antibodies were higher than those of neutralizing antibodies. Thus, the presence of ADCC antibodies was related to the presence of neutralizing antibodies, but no correlation was found between the titres of these antibodies in sera positive for both activities.

Antibody-dependent cellular cytotoxicity-inducing antibodies against human immunodeficiency virus. Presence at different clinical stages

The presence of antibodies mediating antibody-dependent cellular cytotoxicity (ADCC) against human immunodeficiency virus (HIV)-infected target cells was investigated with 170 sera from patients with varying severity of HIV infection. Approximately 40% of sera from individuals representing all stages of infection were ADCC-positive when tested against HTLV-IIIB infected 0937 clone 2 target cells. The positive sera had higher HIV antibody titers as measured by enzyme-linked immunosorbent assay compared with ADCC-negative sera. ADCC titers were lower in patients with acquired immune deficiency syndrome than in asymptomatic carriers. This decline in ADCC titer was not correlated with a general decrease of HIV antibodies. No correlation between the CD4:CD8 lymphocyte ratio and ADCC activity was found. The possible beneficial effect of ADCC-inducing antibodies early in infection is discussed in relation to the effect of ADCC-inducing antibodies in other retrovirus systems and to the nature of lentivirus infections.

Antibody-dependent cellular cytotoxicity-inducing antibodies against human immunodeficiency virus. Presence at different clinical stages

The presence of antibodies mediating antibody-dependent cellular cytotoxicity (ADCC) against human immunodeficiency virus (HIV)-infected target cells was investigated with 170 sera from patients with varying severity of HIV infection. Approximately 40% of sera from individuals representing all stages of infection were ADCC-positive when tested against HTLV-IIIB infected 0937 clone 2 target cells. The positive sera had higher HIV antibody titers as measured by enzyme-linked immunosorbent assay compared with ADCC-negative sera. ADCC titers were lower in patients with acquired immune deficiency syndrome than in asymptomatic carriers. This decline in ADCC titer was not correlated with a general decrease of HIV antibodies. No correlation between the CD4:CD8 lymphocyte ratio and ADCC activity was found. The possible beneficial effect of ADCC-inducing antibodies early in infection is discussed in relation to the effect of ADCC-inducing antibodies in other retrovirus systems and to the nature of lentivirus infections.

Immunoglobulin levels in haemophiliacs at HIV seroconversion and during follow up

Immunoglobulins and aminotransferases were followed in 66 haemophilia patients and 13 von Willebrand patients over a six-year period. The results were correlated to HIV serology and lymphocyte subsets. Elevated IgG levels were found in 29/53 patients with haemophilia A, 2/13 with haemophilia B and in 0/13 with von Willebrand's disease. Elevated IgA and IgM levels were seen in 20% and 27% of the patients respectively, with a distribution similar to the elevated IgG levels, except that elevated IgA and IgM levels were also seen in 4/13 patients with von Willebrand's disease. Patients with HIV antibodies had significantly higher immunoglobulin levels than seronegative patients, and this elevation occurred in connection with seroconversion in the majority of the former. The IgG levels could not be correlated to the T4 cell count, but there has been a trend to less clinical symptoms related to HIV infection among those with stable IgG levels during the past few years. No correlation was found between elevated IgG levels and the aminotransferase levels, nor was any correlation found with the amount of blood coagulation factor concentrate given to the patients. The elevation of immunoglobulins observed in our haemophiliacs is multifactorial, but HIV infection is maybe the most important mechanism. The longitudinal IgG pattern may contribute to the prediction of the clinical outcome of this infection.

HIV seroconversion in Swedish haemophiliacs: relation to type and dosage of factor concentrate

Human immunodeficiency virus (HIV) seroconversion among 40 Swedish haemophilia A patients has been investigated by retrospective sera testing. 22/40 patients had developed HIV antibodies before 1983, i.e., when heat-treatment of American factor concentrates was introduced. All patients had received American and Swedish factor concentrates, thus no case of seroconversion was seen among patients treated exclusively with non-heat-treated Swedish concentrates. Of 79 patients with severe or moderate haemophilia, all of whom had received both American and Swedish concentrates, the 36 seropositives were compared with the 43 seronegatives. The total number of units received did not differ between the two groups, though the seropositive group had received significantly more American concentrate. Two batches of concentrate were proved to have been infected. 29 seropositive and 13 seronegative patients had been treated with at least one of these batches. As expected, and unlike most of the seronegative patients, patients in the seropositive group generally had abnormal lymphocyte subsets.