[Analysis of the replication kinetics in primary culture of isolates of HIV-1 from infected patients in various stages of the disease]

The authors have studied the replicative kinetics and the induction of cytopathic effects of HIV-1 in primary co-cultures from infected subjects at various stages of the disease. Cultures from subjects with ARC or AIDS yielded HIV-1 replication more precociously and at higher levels compared to those from asymptomatic subjects; cytopathic effect "in vitro" were observed more frequently and earlier in cell cultures from ARC/AIDS subjects. Presented data indicate that the clinical and immunological deterioration during HIV-1 infection is related to viral replicative activity and suggest that the study of HIV-1 replicative kinetics in primary co-cultures may be helpful in predicting who will progress to AIDS.

Different biological properties of paired HIV-1 isolates from peripheral blood mononuclear cells and cerebrospinal fluid

Seven paired HIV-1 isolates from peripheral blood mononuclear cells (PMCs) and cerebrospinal fluid (CSF) of infected subjects at various stages of the disease were studied for their capacity to replicate in continuous cell lines (Molt-3 and U-937 cells) and to induce cytopathic effects "in vitro". Obtained results indicate that paired HIV-1 isolates from PMCs and CSF of the same patient can differ in their replicative activity "in vitro", suggesting that, at least in some cases, CSF isolates may represent a distinct subtype of HIV-1.

HIV-1 variability and progression to AIDS: a longitudinal study

HIV-1 replicative activity and its relation to the clinical and immunological evolution of infection was studied in a group of 150 HIV-1 seropositive Italian i.v. drug abusers over a 1 year period. HIV-1 was isolated from 90 (60%) subjects; two groups of isolates were distinguished, according to replicative activity "in vitro" and ability to induce cytopathic effects in cell cultures, and were termed "rapid-high" and "slow-low" viruses, in agreement with other workers. Rapid-high viruses were recovered more frequently from patients with ARC/AIDS, while slow-low viruses seemed related to the asymptomatic period of infection. The replicative properties of HIV-1 seem to affect strongly the course of disease. In fact, an important CD4 cell decline occurred in asymptomatic subjects with rapid-high virus infection; asymptomatic subjects with negative viral cultures or with slow-low viruses showed no such decline. Asymptomatic subjects with negative viral cultures had no signs of disease during the observation period, while 9% with slow-low virus and 45% with rapid-high virus progressed to AIDS.

HIV isolation from whole blood: a new approach to HIV detection

The authors present a simple and sensitive culture technique for isolation of Human Immunodeficiency Virus (HIV) from small amounts of heparinized whole blood. This method appeared to be highly sensitive at all stages of disease. Among asymptomatics HIV was isolated from 41.3% of subjects by using peripheral blood mononuclear cells in a standard co-cultivation technique and in 89.6% of cases using whole blood. In the group of AIDS patients, in contrast, HIV isolation rate of the two techniques was the same (94.4%). The presence of detectable p24 Ag in plasma did not affect cultural results and no false positive was observed in the control group. Although further studies are needed to better understand the biological significance of a positive cultural result obtained by this method, HIV isolation from whole blood can be routinely employed, especially when small amounts of blood are available.

Hepatitis B virus clearance from serum and liver after acute hepatitis delta virus superinfection in chronic HBsAg carriers

Clinical, virological, and histological findings in four HBsAg chronic carriers who cleared HBV markers from both serum and liver following HDV superinfection are described. The patients were long-term HBsAg carriers and all were HBV-DNA/HBeAg positive. Liver biopsy, obtained from three of the patients between 5 and 15 months prior to HDV superinfection, showed chronic persistent hepatitis in two and chronic active hepatitis in one. During the follow-up of 9-19 months, the patients completely recovered from acute delta hepatitis with termination of HBsAg carriage and regression of the histological feature of chronic liver damage. These data demonstrate that sometimes HDV is able to induce a permanent inhibition of its helper virus. HDV superinfection probably enhances the immune clearance of infected cells during the replicative phase of chronic HBV infection.

[Virological monitoring in subjects with HIV infection under treatment with zidovudine (AZT)]

The authors report preliminary results of the virological evaluation (performed by serum p24 antigen detection and HIV isolation from peripheral blood lymphocytes) of Zidovudine therapy in 64 anti-HIV positive subjects. Data presented indicate that the administration of therapeutic doses of the drug can efficiently and precociously inhibit viral replication, suggesting that the clinical benefits of the therapy may be related to the anti-viral activity of the drug. However, the anti-viral efficacy of Zidovudine seems to be of limited length; in fact a reactivation of viral replication was observed in most patients during the study.

Ocular manifestations in HIV-seropositive patients

A total of 153 patients with human immunodeficiency virus (HIV) infection underwent complete ophthalmologic examinations for the presence of any eye pathology. We wanted to show a correlation between such pathology and total CD4+ lymphocyte count, believed to be an indicator of immunologic status. The most frequently encountered lesions were cotton-wool patches, vascular congestion, hemorrhages, chorioretinitis, segmental vasculitis, and pallid papilla. Almost all of the patients with ocular anomalies also had a CD4+ count of less than 200 cells/mm3 suggesting that ocular lesions have a negative prognostic significance even in asymptomatic patients who present with a severe impairment of their immune system.

[Technical note on the isolation of HIV from peripheral lymphomonocytes: use of PHA]

As a part of ongoing study about the role that different technical factors may play in influencing the sensibility of HIV isolation procedures, the authors have evaluated the effects of PHA stimulation of infected cells on HIV replication in cell cultures. Data presented demonstrate that the use of PHA in cell cultures for HIV isolation causes a slower viral replication and, in some cases, inhibits HIV growth.

Risk of AIDS in HIV seroconverters: a comparison between intravenous drug users and homosexual males

A multicentre cohort study was conducted in Italy to estimate the risk of developing AIDS in 261 intravenous drug users and 89 homosexual males for whom the seroconversion period was known. Four years after HIV seroconversion, AIDS incidence, estimated by Kaplan-Meier survival technique, was 13.8% for intravenous drug users and 16.2% for homosexual males; the difference was not statistically significant. These findings suggest that four years after seroconversion the risk of developing AIDS in HIV seropositive intravenous drug users is no higher than that of subjects who acquired HIV infection through sexual contact.

[Correlation of viral replication activity, the clinical phase of the disease and immunologic deterioration in HIV infection]

The authors have studied the relationship among HIV replicative activity, expressed by HIV isolation from peripheral blood lymphocytes and p24 antigenemia detection, and the evolution of infection, in terms of stage of disease and T4 cells absolute number, in a group of 120 infected subjects. Data presented indicate that the expression of viral gene products is related both to clinical and immunological deterioration and suggest that viral replication plays a central role in the progression of the disease.

[Isolation of the human immunodeficiency virus (HIV) from the cerebro-spinal fluid]

The authors describe a simple and available technique for HIV isolation from cerebrospinal fluid and report preliminary results obtained. Exposed data indicate that neurological involvement occurs early in the natural history of HIV infection and that the virus may be recovered in CSF at all stages of the disease, regardless of immunological conditions of patients. Virological evaluation of CSF may be important in understanding pathogenetic aspects of HIV infection and in clinical management of infected patients.

[The discordance between the presence of identifiable p24 antigen in the blood and the isolation of HIV from the blood is not influenced by methodological factors]

To clarify the biological, clinical and prognostic relevance of HIV isolation from plasma and explain the relation to p24 antigenemia, we studied these two markers in 67 anti-HIV positive subjects in different stages of the disease. The results suggest that discordances between these two parameters are not dependent on methodological problems and may be attributed to yet unexplained biological phenomena. Some hypotheses to explain the observed discrepancies are suggested.

[Intrathecal synthesis of IgG in HIV infections]

CSF and serum of 80 HIV-seropositive patients in various stages of the disease were examined. Total as well as intrathecal IgG synthesis appeared to be frequently elevated in each diagnostic group. Abnormal CSF oligoclonal IgG fractions were significantly more frequent in asymptomatic patients. CSF pleocytosis was found with a lower percentage in neurological AIDS patients. In patients subdivided according to blood T helper cell count, the distribution of the abnormal CSF parameters confirms that the immunological response in the CNS is mediated by interaction with systemic immunity.

Clinical and immunological assessment in HIV+ subjects receiving inosine-pranobex. A randomised, multicentric study

Inosine-pranobex (methisoprinol, isoprinosine; INPX) is the p-acetamidobenzoic salt of N,N-dimethylamino-2-propanol and inosine in a 3:1 molar ratio. In early studies, INPX was found to partially inhibit human immunodeficiency virus (HIV) and to increase the immunocompetence of HIV-infected subjects in vitro. We report the results of a randomised, multicentric clinical trial carried out on 553 HIV+ patients. 261 individuals were treated with INPX (two 500 mg tablets every 6 h for 3 months) and the remaining 292 constituted the untreated control group. INPX treatment was associated with a slightly improved clinical condition or with a trend in that direction, as compared to the untreated group. A preservation of the CD4/CD8 cell ratio values, a decrease in the CD8+ cells and an increase in the Leu 2-7+ cell number better than in the untreated individuals was also observed in the patients taking INPX. No serious or adverse effects of INPX have been observed.

The natural history of HIV infection in intravenous drug users: risk of disease progression in a cohort of seroconverters

A multicentre cohort study was carried out to estimate the incidence of AIDS and HIV-related conditions in newly infected intravenous drug users (IVDU). The enrollment criteria included the identification of the seroconversion time. Two hundred and five subjects entered the study, and were followed for a mean of 26 months. Twelve subjects developed clinical AIDS over a 4-year period. The actuarial incidence of AIDS estimated by Kaplan-Meier survival technique was 17.8% by 4 years since seroconversion. The risk of developing AIDS increased significantly after 24 months from seroconversion. Relatively small figures accounted for the lack of statistical association between the risk factors investigated and the disease status.

Effects of HIV superinfection on HBV replication in a chronic HBsAg carrier with liver disease

A case of HIV superinfection observed in an HBsAg/HBeAg-positive male homosexual with chronic persistent hepatitis is described. Soon after the appearance of clinical and serological features of acute HIV infection, a rapid fall to a normal value of ALT was noted with simultaneous recrudescence of HBV replication lasting for several months as detected by an increase of the HBV-DNA concentration in the serum. Our observations suggest that the reduction of hepatocyte necrosis and the increase in HBV replication were a consequence of impaired T cell function during acute HIV infection.

Permanent inhibition of viral replication induced by low dosage of human leukocyte interferon in patients with chronic hepatitis B

Fourteen out of 28 HBsAg/HBeAg-positive carriers with chronic persistent and active hepatitis were randomly assigned to human leukocyte interferon (a-IFN) treatment for three months. The remaining 14 patients served as controls. Each treated subject received a standard i.m. dose of 0.7-1.0 X 10(5)/kg/day reference units of a-IFN for 28 consecutive days, and then the same dose twice a week for two months. This treatment regimen was well tolerated, and no remarkable side effects were recorded. At six months the number of patients who permanently lost HBV-DNA from serum was significantly higher in the treated group (p = 0.006) than in the untreated group. These results suggest that a less expensive and well tolerated treatment regimen based on low dosage of a-IFN may be as effective in producing permanent inhibition of hepatitis B virus replication as a treatment regimen based on larger dosage.

Cryptosporidiosis in the acquired immunodeficiency syndrome: a case report

A case of cryptosporidiosis in a male homosexual man with AIDS is reported. The clinical manifestations were anorexia, mild fever, abdominal pain and profuse watery diarrhea. The diagnosis was made in fecal smears by using a modified Ziehl-Neelsen method and a safranin-methylene blue staining technique.

Serum IgA anti-hepatitis A virus as detected by enzyme-linked immunosorbent assay. Diagnostic significance in patients with acute and protracted hepatitis A

A capture enzyme-linked immunosorbent assay for the detection of serum IgA against hepatitis A virus has been developed. The test was highly specific, and the time course of detectability of IgA anti-HAV was longer than six months in 42/42 patients with acute or protracted hepatitis A followed prospectively, but shorter than two years in 14/14 patients tested 21-24 months after diagnosis of acute hepatitis A. IgM anti-HAV were at detectable levels in only 1/42 cases tested six months after the clinical onset. The detection of serum IgA anti-HAV is a simple and specific method to differentiate protracted cases of hepatitis A from non-A, non-B hepatitis.

Monophasic and polyphasic pattern of alanine aminotransferase in acute non-A, non-B hepatitis. Clinical and prognostic implications

One-hundred-and-two out of 788 consecutive patients (12.9%) hospitalized for an attack of acute hepatitis fulfilled criteria for non-A, non-B (NANB) hepatitis, and were followed prospectively for 8 to 70 months. Forty-one out of 97 patients showed a monophasic pattern of alanine aminotransferase (ALT), and all recovered completely. In contrast, 22 of 56 (39.2%) subjects with a polyphasic pattern of ALT exhibited persistent hypertransaminasemia for more than 14-18 months, and all of them developed chronic hepatitis. Thus, a polyphasic pattern of ALT seems to characterize one of two forms of NANB hepatitis, more frequently associated with parenteral exposure, absence of jaundice and a high tendency for the development of chronic hepatitis. This suggests distinct immunopathogenetic mechanisms from two unrelated NANB agents. Benign, non-progressive chronic persistent hepatitis is the prevalent form of chronic sequela of NANB hepatitis observed in our patients. Although many of these patients show a tendency to spontaneous remission of the disease, there is the possibility in some of a deterioration of inflammatory activity of the liver that has need of immunosuppressive therapy.

Comparison of three enzyme-linked immunosorbent assays suitable for the detection of antibodies to rotaviruses in epidemiological studies

Three enzyme-linked immunosorbent assays which use commercially available reagents are presented as alternatives to the complement fixation procedure for large-scale detection of rotavirus antibodies. Comparison of results in 75 sera tested by indirect, competition and blocking ELISA and by complement fixation demonstrated that the ELISA techniques were rapid, easy to perform and 26 to 29 times more sensitive than complement fixation; furthermore the ELISA techniques permitted extrapolation of an approximate titer from a single dilution test. Although it could detect class-specific antibodies, the indirect assay was less sensitive, specific and reproducible than competition and blocking assays; furthermore the titer extrapolated from a single dilution test in the indirect assay had a lower correlation with the end-point titer than in the other two methods. Competition ELISA was easier to perform whereas blocking ELISA had better reproducibility and serotype studies were possible with it using faecal rotavirus isolates. The respective ELISA technique can be recommended for use in seroepidemiologic surveys according to the study needs.

[Evaluation of an immunoenzyme test (ELISA) for the determination of an Ag/Ab system correlated to non-A, non-B post-transfusion hepatitis]

An ELISA for the detection of a Ag/Ab system related to non-A, non-B post-transfusion hepatitis (NANB-PTH) has been developed. A convalescent serum from a patient suffering, 14 month before, of NANB-PTH was used both as capture and detector antibody in a "sandwich" type immunoassay to detect an Ag (Ag-NANB). A "blocking" immunoassay was used, in the same test, to detect the corresponding antibody (Ab-NANB). All patients with NANB-PTH were positive, alternately, for Ag-NANB or Ab-NANB. The Ag was found in the acute phase sera of 3 out of 22 cases of NANB-PTH (13,6%), but in none of 29 acute hepatitis type B,26 acute hepatitis type A,14 NANB sporadic hepatitis, 5 infectious mononucleosis and 8 healthy subjects. 2/3 Ag-NANB positive subjects became chronic carriers of this Ag, whereas the third seroconverted for Ab-NANB after the first two months of their disease. Furthermore, a significant increase of the Ab-NANB titer was observed in the convalescent phase of the disease in 18/20 NANB-PTH. As expected, a relatively high prevalence for Ab-NANB was found in the other groups of patients, suggesting the high diffusion of the agent, but none of these subjects showed a progressive increase of the antibody titer during the course of their disease.

New principle for the simultaneous detection of total and immunoglobulin M antibodies applied to the measurement of antibody to hepatitis B core antigen

A new test principle for the simultaneous detection of total approximate titers and immunoglobulin M antibodies has been developed and applied to the detection of antibody to hepatitis B core antigen. The method is based on the combination of a competition radioimmunoassay, for the determination of total antibody titer, with an indirect enzyme-linked immunosorbent assay for the determination of single class antibodies. The interference of the rheumatoid factor was avoided by including heat-aggregated immunoglobulin G in the dilution buffer. The specificity, sensitivity, and clinical application of the test are discussed. The results presented suggest that the simultaneous detection of total and immunoglobulin M antibody to hepatitis B core antigen might be helpful in the differentiation between previous and recent or ongoing hepatitis B infection, as well as in the differential diagnosis of acute hepatitis, in monitoring viral activity in chronic infections, and in helping to differentiate acute from chronic infections. The test principle appears applicable in the accurate diagnosis of other infectious diseases by a single test on only one serum sample.

[Behavior of theophylline-sensitive T lymphocytes in viral A, B, non-A, non-B hepatitis. I. Methodological aspects]

To evaluate the behaviour of the Theophylline-sensitive T lymphocytes subpopulation some modifications of the standard procedure are proposed. Lymphoprep purified lymphocytes were counted in a Neubauer hemocytometer after Acridine Orange stain, viability was evaluated by Ethidium Bromide counterstain and monocytes contamination was evaluated by the peroxidase stain. Sheep red blood cells were treated with AET, Theophylline was used at 3 mM (final concentration) and the results compared with untreated lymphocytes; the enumeration of the rosetting lymphocytes was facilitated by adding Acridine Orange prior to the resuspension. The modifications described were able to increase the % of rosetting T lymphocytes, to eliminate differences depending by different lots of sheep red blood cells and to decrease differences depending by subjective evaluation of the rosetting T lymphocytes.

[Immunoenzyme determination of IgA specific anti-HAV in the serological diagnosis of hepatitis A]

A capture enzyme immuno assay for the detection in the serum of specific IgA antibodies to HAV is described. A total of 203 sera from patients and controls were tested. IgA anti-HAV were present only in sera from patients with recent hepatitis A. 23 patients were followed prospectively and IgA anti-HAV were at detectable levels for at least six months after the onset. The detection of IgA anti-HAV is proposed as an important test to differentiate hepatitis A with persistent hypertransaminasemia from non-A, non-B patients.

[Behavior of theophylline-sensitive T lymphocytes in viral A, B, non-A, non-B hepatitis. II. Application aspects]

The pathogenesis of the hepatic damage in hepatitis is not well understood but an imbalance in immunoregulatory T lymphocytes is probable. We tested the Theophylline-sensitive T lymphocytes in acute and protracted cases of hepatitis A, in hepatitis B and non-A, non-B. A delayed increment of such cells was demonstrated in hepatitis B suggesting a positive role in the recovery from the disease. The results were indicative for a direct action of the HAV and nAnB on the lymphocytes. Theophylline-sensitive lymphocytes were increased in the course of protracted hepatitis A whereas were progressively decreasing in nAnB hepatitis. This behaviour of suppressor cells in nAnB hepatitis may explain the high frequency of evolution in chronic liver disease.

Circulating immune complexes in HBsAg-positive and HBsAg-negative chronic liver diseases

Circulating immune complexes (CIC) were investigated by the fluid-phase C1q-binding test in serum samples from 131 subjects with various clinical types of HBsAg-positive and HBsAg-negative chronic hepatitis diagnosed on both clinical and laboratory criteria, including liver biopsy; serum samples from 28 asymptomatic HBsAg carriers and 75 healthy controls were also examined. The results of these findings were correlated with the liver damage and the clinical course of the disease. CIC were detected in all categories of chronic hepatitis with a significant prevalence only in patients with liver cirrhosis. No correlation was found between the levels of CIC, the presence of circulating HBsAg, and active inflammation or necrosis in any of the different types of chronic hepatitis. In contrast, a highly significant correlation was found between the prevalence of CIC and a more severe prognosis in patients with CAH and liver cirrhosis. The findings suggest that the presence of CIC is not specific for a given type of chronic liver disease and that they do not play any role in the pathogenesis of liver damage. The correlation observed between the presence of CIC and an unfavourable course of chronic liver disease suggests that CIC may modify the host's immune defence mechanisms.

[Evaluation of free and IgG-bound components of e antigen (HBeAg) in acute virus B hepatitis]

Soluble (free) and insoluble (IgG-bound) hepatitis B e antigen (HBeAg) activities in 1,33 M ammonium sulfate solution was evaluated serially in sera from 12 patients with acute type B hepatitis followed up to 60 days. In three cases preclinical sera were available. In patients who showed clinical and biochemical resolution of hepatitis within 60 days, HBeAg free was the prevalent form of circulating HBeAg during the incubation period of disease, then gradually shifting to the IgG-bound form at the onset of jaundice. Finally HBeAg-bound was no longer demonstrable, followed by detection of anti-HBe antibody. On the contrary, in all patients with unresolved hepatitis both HBeAg-free and HBeAg-bound were detected with prevalence of HBeAg-free ratio. These data suggest a striking correlation between synthesis of HBeAg and HBV replication and may indicate that HBeAg-free and IgG-bound ratio reflects the stage and prognosis of acute HBV infection.

Characterization of the circulating immune complexes in acute and chronic liver diseases

The composition of immune complexes (IC) found in 28 patients with HBsAg positive and negative acute and chronic hepatitis was analysed. Components were defined in PEG-precipitated material isolated by preparative ultracentrifugation on linear sucrose density gradients and analysed by the Ouchterlony plate technique and by the radioimmunoassay of hepatitis B virus markers. Sedimentation rate ranged from 8 to 19s in the serum of patients with chronic hepatitis, whereas heavier IC (greater than 19s) were present in the active phase of the disease. The participation of hepatitis B virus in acute hepatitis was shown by the presence of its antigens. In contrast, a low incidence of vital components was seen in IC of chronic active hepatitis and liver cirrhosis. Thus, other causes must contribute to the formation of IC in chronic liver disease.

Chronic viral hepatitis in thalassemic liver disease. A long-term study in patients with acute hepatitis with nontransfusion-dependent thalassemia minor

To evaluate the effective role of hepatitis viruses in thalassemic (Th) liver disease, we carried out a long-term study in 42 subjects with nontransfusion-dependent Th minor hospitalized for an episode of acute viral hepatitis. 10 patients had serologic evidence of hepatitis A, 23 of hepatitis B and 9 of hepatitis non-A, non-B. In the follow-up chronic hepatitis was detected histologically in 5/23 patients with hepatitis B and 5/9 with hepatitis non-A, non-B. All hepatitis A patients recovered completely. The prevalence in 7 out of 10 patients with chronic hepatitis of piecemeal necrosis and of inflammatory changes over hepatic siderosis and fibrosis evidenced a determinant role of chronic viral infection in the development of liver damage in these patients. Thus, heterozygous nontransfusion-dependent Th patients seem to have a high risk of developing a chronic inflammatory liver disease especially after an episode of non-A, non-B hepatitis. Therefore, in our geographical area, chronic hepatitis of viral origin should be taken into account, among other pathogenetic factors, in many cases of cryptogenic thalassemic liver disease.

Infectivity markers in HBsAg chronic carriers and intrafamilial spread of hepatitis B virus infection

Sera from 28 HBsAg chronic carriers were tested for the presence of HBeAg, anti-HBe and Dane particle-associated DNA-polymerase activity, in order to evaluate the relationship between the presence of these markers and the spread of HBV infection in their family contacts. A highly significant prevalence of HBV infection was observed in the relatives of HBsAg carriers who were positive for either HBeAg or DNA-polymerase activity or both. These observations support the inference of a striking correlation between the presence of these markers and the infectivity of HBsAg carriers. Therefore, serological determination of HBeAg and DNA-polymerase activity may be considered in the epidemiological control of HBV infection

Hepatitis B virus markers, alpha-fetoprotein and survival in fulminant viral hepatitis

The serological markers of hepatitis B virus and serum alpha-fetoprotein (AFP) levels have been studied in 28 consecutive cases of fulminant hepatitis, correlating the data with survival. On admission, 20 patients were found to be positive for HBsAg and eight for anti-HBs. All anti-HBs-positive cases showed high titers of anti-HBc, and six patients were positive for specific anti-HBc-IgM. DNA polymerase activity was detected in serum of 11 HBsAg-positive (55%) and four anti-HBs-positive (50%) patients. HBeAg was detected in six (21.4%) subjects (five HBsAg-positive and one anti-HBs-positive), whereas anti-HBe was present in nine (32.1%) subjects (six HBsAg-positive and three anti-HBs-positive). AFP levels greater than 60 ng/ml were found in sera of 14 patients (50%). No significant difference was evidenced in the survival rate between HBsAg-positive and anti-HBs-positive and between HBeAg-positive and HBe Ag-negative patients. However, a statistically significant difference (P less than 0.05) in the survival rate was found in patients positive and negative for DNA polymerase activity and in those with AFP levels higher and lower than 60 ng/ml (P less than 0.005). Pathogenetic and prognostic significance of these findings are discussed.

[Markers of viral replication (HBeAg and DNA polymerase activity) in chronic uremia, HBsAg positive, hemodialysis patients]

The contagiousness of hepatitis B virus (HBV) carriers with end-stage renal disease undergoing chronic hemodialysis has been ascribed to an immunologic tolerance for HBV antigens, especially hepatitis B core antigen, supporting persistently high levels of virus replication. In this context hepatitis B e antigen and core-associated DNA polymerase (DNA P) activity have proved to be distinct markers of HBV replication. In order to evaluate the potential infectivity of these subjects, thirty-five HBsAg positive hemodialysis patients were studied for the presence of HBeAg/anti-HBe system correlating the results with serum DNA P activity. Twenty out of 35 patients were HBeAg positive (57%) and 21 DNA P positive (60%). A highly significant correlation (P less than 0,001) was recorded between detection of HBeAg and presence of serum DNA P activity. These findings confirm that the majority of hemodialysis patients carrying HBsAg show high levels of virus replication so that the determination of HBeAg and DNA P activity other than HBsAg is required for the identification of patients highly infectious.

[Serologic diagnosis of acute hepatitis A. Refinement and evaluation of 3 methods of determining specific anti-HAV IgM]

A solid phase radioimmunoassay (RIA) procedure was developed and three methods for detection of IgM specific antibody to hepatitis A virus (anti-HAV IgM) were compared: triple antibody method, 2-MercaptoEthanol (2-ME) for IgM cleavage and Staphylococcal A Protein (StAP) for IgG absorption. Specificity and sensitivity of the tests were checked for evaluating acute and convalescent sera from 40 patients with serologically (seroconversion) diagnosed hepatitis A and 64 sera from patients with various acute viral diseases or with high titre of rheumatoid factor (RF). Specimens to be assayed for anti-HAV IgM were pretreated with 2-ME or StAP and tested by RIa using 125I labelled anti-HAV IgG. Triple antibody method showed to be more sensitive than other two methods giving false positive result in only one serum containing high levels of monoclonal RF. No significant difference in sensitivity and specificity was found between 2-ME and StAP procedure, but these methods were able to detect anti-HAV IgM for only two weeks after the onset of the disease, whereas triple antibody method gave positive results for at last seven weeks.

[Non-A, non-B post-transfusion hepatitis. Serological survey of 85 patients with acute hepatitis following blood transfusion]

In a serological survey of 85 adult patients hospitalized for an episode of transfusion-associated hepatitis, 45 were reactive for hepatitis B surface antigen and therefore diagnosed as having hepatitis B. Forty HBsAg non reactive patients were examined for development of antibody to hepatitis A and B antigens, cytomegalovirus and Epstein-Barr virus. Three patients showed serologic evidence of hepatitis B and one for hepatitis A. None of the remaining 36 subjects developed serologic evidence of acute infection with the viruses tested during the study period, so that they were classified as having so-called NANB hepatitis. As reported in other studies, analysis of the incubation period showed that two subgroups of NANB hepatitis may be identified with short and long incubation period, so that it appears likely that at least two agents are implicated in NANB hepatitis. Our data confirm that also in our area a large proportion of transfusion-associated hepatitis is related to NANB agent(s) requiring additional measures for its prevention.

Radioimmunoassay in the detection of the hepatitis B e antigen/antibody system in asymptomatic carriers of hepatitis B surface antigen. Correlation with serum Dane particle associated DNA polymerase activity

A radioimmunoassay for hepatitis e antigen (HBeAg) and antibody to e (anti-HBe) was developed and sera of 71 asymptomatic chronic carriers of hepatitis B surface antigen (HBsAg), in 44 of whom liver biopsy was obtained, were tested. In addition, testing for Dane particle associated DNA polymerase activity was performed in all sera. HBeAg was detected in 14 subjects (19.7%) and anti-HBe in 46 (64.8%). The highest proportion of HBeAg positivity (40%) was found among carriers with histological evidence of chronic hepatitis, whereas anti-HBe was present in 80% of carriers with normal liver histology, in 58% of carriers with non-specific reactive hepatitis and in 60% of carriers with chronic liver lesions. DNA polymerase activity was present in 92.8% of sera positive for HBeAg, in 13% of sera positive for anti-HBe, and in 9% of sera negative for both markers. Our results demonstrate that not all HBsAg carriers reactive to HBeAg show evidence of chronic hepatitis nor, conversely, that anti-HBe is invariably associated with the healthy carrier state of HBsAg. Finally, circulating Dane particles, as revealed by the presence of serum specific DNA polymerase activity, may also be present in anti-HBe positive sera other than those of some HBsAg carriers lacking both HBeAg and anti-HBe.

[Distribution of anti-HAV in a population sample from Puglia]

To investigate the prevalence and distribution of antibody to hepatitis A virus (anti-HAV), we tested by solid phase radioimmunoassay method 461 sera of selected people of Bari, according to age. In addiction, sera from cord blood of 11 newborns and their mothers at delivery were also investigated for anti-HAV. Taken together 64.4 per cent of subjects tested were found to be anti-HAV positive. The rate of antibody detection was strongly correlated with age. The prevalence were 4.5 per cent from 6 months to 3 years but gradually increased throughout childhood (from 35.6 to 80 per cent). Anti-HAV was detected in all cord blood samples from newborns whose mothers carried anti-HAV. These data suggest that circulation of hepatitis A virus in our area is very high, so that serological evidence of infection become evident in the majority of individuals during infancy.

[Antinuclear antibody (anti-HBc) and liver pathology in acute and chronic virus B hepatitis]

HBsAg and anti-HBc, the antibody to core antigen of hepatitis B virion, were titrated by solid phase radioimmunoassay in 40 sera of HBsAg carriers with acute and chronic hepatitis and in 20 healthy subjects carrying anti-HBc alone or associated with anti-HBs. No correlation was found between HBsAg and anti-HBc titers in the single category of patients. In contrast, geometric mean titer of anti-HBc (ranging from 2(14) to 2(15)) of patients with chronic active hepatitis was significantly higher ( p = < 0.01) than that of patients with acute or chronic persistent hepatitis and healthy HBsAg carriers (ranging from 2(9) to 2(14)). Anti-HBc titer of 20 subjects without detectable HBsAg was less than 2(7). These data suggest that in subjects with persistent B virus infection, anti-HBc response is correlated with synthesis of viral genome rather than of surface antigens, so that a much higher titer of anti-HBc was detected only in patients with a more active liver disease.

[Serodiagnosis of acute hepatitis A]

Hepatitis A antibody (anti-HAV) was detected by specific radioimmunoassay (RIA) method in sera from 10 patients with acute icteric hepatitis. Anti-HAV was detectable in many subjects very early before the onset of jaundice, but the diagnosis of type A hepatitis in all patients was confirmed by the demonstration of seroconversion during convalescence. Since the initial antibody detected by RIA is predominantly IgM, while IgG specific anti-HAV appears later reaching peak levels within 1 to 2 months, we treated serum specimens of these patients with 2-mercaptoethanol (2ME) in order to differentiate acute-from convalescent-phase hepatitis A sera. Inactivation of IgM fraction with 2ME produced a significant reduction of anti-HAV titer only in acute-phase sera, so that this procedure may be used for early diagnosis of acute type A hepatitis.