Quantification of neutrophil and monocyte CD64 expression: a predictive biomarker for active tuberculosis.

SETTING: QuantiFERON TB assay (QFT) is used to screen tuberculosis (TB) infection, but it cannot distinguish active TB from latent TB infection (LTBI).OBJECTIVE: To evaluate the quantitative expression of the high-affinity FCgamma receptor I (CD64) on neutrophils (NE) and monocytes (MO) in peripheral blood using flow cytometry, measured in antibody binding capacity (ABC) units as a predictive biomarker of TB.DESIGN: Fifty-two patients were enrolled (45 QFT-positive and 7 QFT-indeterminate). Cultures and molecular analyses were performed.RESULTS: Of the 45 QFT-positive patients, 29 were culture-positive (active TB) and 16 were negative (LTBI). The median NE CD64 ABC and MO CD64 ABC expression was significantly higher (P < 0.001) in culture-positive patients. The NE CD64 and MO CD64 area under the receiver operating characteristic curve values were respectively 0.948 (95%CI 0.838-0.992) and 0.989 (0.901-1.000). By setting the cut-off NE CD64 value at >2400 ABC or MO CD64 value >25 800 the assay sensitivity increased to 95.5% with 100% specificity and 100% positive predictive value. In the QFT-indeterminate group, five culture-positive cases had NE CD64 >2400 ABC or MO CD64 value >25 800; two culture-negative cases had lower values.CONCLUSION: The CD64 quantitative expression on peripheral blood cells may be used as a predictive biomarker for active TB.

Epidemiology of hepatitis D virus (HDV) infection in an urban area of northern Italy.

OBJECTIVES: The introduction of vaccination against hepatitis B initially reduced the number of HBV (hepatitis B virus) and HDV (hepatitis delta virus) infections, but the decreasing trend of HDV infection seems to have stopped. The aim of this study was to assess the prevalence of HDV infection in the general population living in the catchment area of Legnano Hospital in northern Italy. METHODS: Of the 22,758 subjects tested in 2007-2008, the 488 who were HBsAg (hepatitis B surface antigen)-positive [including 107 (21.9%) of non-Italian origin] were subsequently tested for anti-HDV antibodies. RESULTS: Of the 488 subjects who tested positive for HBsAg, 24 (4.9%) were anti-HDV positive, all aged between 30 and 60 years. The difference in prevalence between males (7.1%) and females (1.9%) was statistically significant (p < 0.05), but not that between Italian (5.0%) and non-Italian patients (4.7%). The differences in anti-HDV seropositivity between the patients with acute (0%) and chronic infections (6.3%), and between the incident (2.5%) and prevalent cases (7.4%), were not statistically significant, but there was a significant difference (p < 0.01) between those with asymptomatic (2.1%) and clinically symptomatic infections (10.3%). Intravenous drug abuse was the main source of infection. CONCLUSIONS: In the catchment area of our hospital, the prevalence of HDV infection does not seem to be due to patients of non-Italian origin, but to Italian patients who are not vaccinated against HBV and who survived the HDV epidemic of the 1970s and 1980s. Nevertheless, the increase in the number of immigrants from non-EU countries in recent years is soon likely to lead to a change in the epidemiology of HDV.

Epidemiology of HIV-1 subtypes in an urban area of northern Italy.

The distribution of the different subtypes of HIV varies from one region of the world to another. Subtype B is predominant in Europe and the USA, but there has been a gradual increase in non-B subtypes as a result of migration from regions where they are endemic, and this may have important implications for the control of HIV-1. The aim of this study was to assess the prevalence of HIV-1 subtypes in an urban area of northern Italy in the period 1997-2008. Forty-nine (12.2%; 95% CI, 9.00-15.40) of 401 patients investigated carried a non-B subtype, the prevalence of which was 7.7% (95% CI, 4.96-10.44) among native Italians and 55.3% (95% CI, 39.49-71.11) among non-Italians, 1.6% (95% CI, 0.00-3.81) among ex-intravenous drug addicts, 7.6% (95% CI, 1.21-13.99) among homosexual/bisexual men and 20.5% (95% CI, 14.83-26.17) among heterosexuals, 6.8% (95% CI, 3.37-10.23) among Italians infected as a result of sexual contacts in Italy, and 55.0% (95% CI, 33.20-76.80) among Italians infected abroad or by foreign partners. Overall prevalence increased from 2.9% (95% CI, 0.00-6.11) before 1993 to 23.0% (95% CI, 16.31-29.69) in the period 2001-2008. The results demonstrate that there has been an increase in non-B subtypes (especially sexually transmitted infections), particularly among patients infected abroad or by foreign partners.

Seroprevalence and incidence of Toxoplasma gondii infection in the Legnano area of Italy.

The decreasing prevalence of anti-Toxoplasma antibodies in Europe has re-opened the question of the appropriateness of serological screening during pregnancy. A study of 3426 pregnant women, resident in the Legnano area of Italy, revealed that the IgG seroprevalence according to ELISA was 21.5%, and that of IgM according to ELISA and enzyme-linked fluorescent assay was 1.2% and 0.9%, respectively. The incidence of infection, estimated on the basis of IgG avidity, was 0.9%. These results confirm a decrease in the prevalence of IgG, but indicate a high incidence of infection, thus suggesting that screening for anti-Toxoplasma antibodies during pregnancy should be maintained.

Absolute TCD4+ counting by a minimalist dual-platform flow cytometric method.

UNLABELLED: The aim of this work was to compare the performance of an absolute TCD4+ counting method based on total WBC gating versus the standard lymphocyte (Ly) gating method, in order to develop a flow cytometric (FCM) minimalist strategy for TCD4+ enumeration. METHOD: 132 routine peripheral blood samples, mainly from HIV infected patients, were labelled with CD3-FITC/CD4-PE/CD45-PECy5 and analyzed by two gating methods: a) standard method based on Ly immunological gating (CD45++SSClow), followed by the determination of CD3+CD4+ percentage and absolute number (# calculation using Ly # from hematological analyser (HA); b) total WBC immunological gate on biparametric scatter CD45/CD4, followed by CD4++SSClow percentage determination and absolute number calculation using WBC absolute number from hematological counter without using the WBC differential. Moreover on 63 samples Ly # based on Ly % from FCM and WBC counting from HA was compared with Ly # from HA. RESULTS: The TCD4+/microL ranged from 3 to 3277 and the statistical analysis results showed: a) linear regression: r2 = 0.9847; b) Bland & Altman analysis: difference mean = -56.22; agreement range = +95.68 / -208.12; c) the mean of result difference/mean value*100 between two methods was -9.06%; d) comparison between regression line and the boundaries for acceptable residual values based on regressed confidence limits found by A. Kunkl et al showed regression line within boundaries near the upper limits. The Ly/microL count ranged from 635 to 8752. The statistical analysis results showed: a) linear regression: r2 = 0.9764; b) Bland & Altman analysis: difference mean = -362.93; agreement range = +134.51 / -860.37; c) the mean of result difference/mean value*100 between two methods was -16.12%. CONCLUSIONS: Our results suggest a fair agreement between the two gating methods, but the one based on total WBC gate gives TCD4+/microL counts systematically higher than the standard method. This finding can be attributed to a systematic lower estimation of Ly% by HA.

Association between neonatal blood microtransfusions in the 1960s and hepatitis C virus infection.

In the 1960s, a common practice in Italy was to give a few mL of blood or plasma to underweight or preterm newborns. We postulated that this practice might be the cause of hepatitis C virus (HCV) infections seen today in adults with a negative history, and no recall of such transfusions. We examined the transfusion files of children admitted to the Department of Paediatrics during 1968-74, and found that 613 children had been transfused within the first year of life. Of 57 traceable patients, 28 are now positive for antibodies to HCV, 17 of whom received at least one microtransfusion from a common donor who is also positive.

Acute hepatic toxicity during cyclic chemotherapy in non Hodgkin's lymphoma.

BACKGROUND AND OBJECTIVE: Hepatic toxicity directly related to the drugs administered in cyclic chemotherapy (CT), although sometimes serious, does not limit the treatment of non-Hodgkin's lymphoma (NHL). Nevertheless, reports of reactivation of viral hepatitis in NHL patients with B virus (HBV) infection are becoming more frequent. The recent observation of two cases of severe liver toxicity directly correlated to CT and a case of fatal hepatic failure due to HBV replication prompted us to evaluate the hepatic toxicity of CT in 98 consecutive B-cell NHL patients treated with relatively homogeneous cyclic CT. METHODS: Acute hepatic toxicity was retrospectively evaluated in 98 consecutive B-cell NHL patients who received induction CT. HBV and HCV markers were checked at presentation. All patients were tested for ALT and bilirubin before every CT course, while tests for HBV-DNA and/or for HCV-RNA were performed with PCR only when hepatitis occurred. RESULTS: At presentation 22 patients (22.4%) were positive for HBsAg, and 11 (15.9%) were positive for anti-HCV. Acute hepatitis developed in 12 (12.2%) NHL patients: 8 (out of 22) in HBsAg-positive and anti-HCV-negative patients, 3 (out of 76) in HBsAg-negative patients, and 1 (out of 11) in anti-HCV-positive patients. Hepatitis was attributed to reactivation of chronic B hepatitis in 3 patients and to drug toxicity in 3 others; hepatitis was undefined in 6 cases. INTERPRETATION AND CONCLUSIONS: Drug-related liver toxicity is not a rare occurrence in NHL patients. Reactivation of HBV replication is responsible for a relevant number of the hepatitis cases observed. We did not detect acute hepatitis due to the reactivation of HCV replication (in chronic C hepatitis carriers).

Hepatitis B vaccination of 113 hemophiliacs: lower antibody response in anti-LAV/HTLV-III-positive patients.

One-hundred thirteen adults and children with hemophilia or other congenital bleeding disorders were vaccinated against the hepatitis B virus. Each patient was given three subcutaneous injections of the vaccine at monthly intervals and then a fourth booster dose 14 months after the first. The vaccine was highly immunogenic, since 111 of 113 patients (98%) produced anti-HBs (10 mIU/ml or more). After the first three vaccine doses and after the booster dose, ten anti-LAV/HTLV-III-positive hemophiliacs produced anti-HBs but had a lower average titer than anti-LAV/HTLV-III-negative hemophiliacs. Of the 23 patients treated with concentrates in the 15 month postvaccination period only, none acquired HBV infection. Of the 50 patients treated with concentrates also in the 6 month prevaccination period, one developed hepatitis B. In summary, the vaccine was highly immunogenic in both children and adults with hemophilia; anti-LAV/HTLV-III-positive patients responded to the vaccine, but the average anti-HBs response was lower; no case of hepatitis B occurred in patients treated with concentrates only in the postvaccination period.

[Evaluation of an immunoenzymatic method for the simultaneous determination of HBsAg and anti-HBs]. / Valutazione di un metodo immunoenzimatico per la determinazione contemporanea dell'HBsAg e dell'anti-HBs.

In this study we have evaluated an enzymeimmunoassay for the simultaneous detection of HBsAg and anti-HBs. The EIA method was found to determine anti-HBs at titer of about 10 mIU/ml and HBsAg between 1.5 and 2.5 EU/ml for both ad and ay subtypes. Detection of HBsAg and anti-HBs by EIA and RIA in sera collected from healthy subjects and in patients with acute or chronic hepatitis showed a concordance, respectively, of 98.2 and 97.4%. The discrepancies were in part due to the higher sensitivity of RIA respect to EIA method, while in some cases EIA seems to detect anti-HBs earlier than RIA. The EIA method might be effectively employed in pre-vaccine screening and in the serological follow-up of individuals who received anti-hepatitis B vaccine.