Antibodies Induced by Smallpox Vaccination after at Least 45 Years Cross-React with and In Vitro Neutralize Mpox Virus: A Role for Polyclonal B Cell Activation?

AIMS

To evaluate whether antibodies specific for the vaccinia virus (VV) are still detectable after at least 45 years from immunization. To confirm that VV-specific antibodies are endowed with the capacity to neutralize Mpox virus (MPXV) in vitro. To test a possible role of polyclonal non-specific activation in the maintenance of immunologic memory.

METHODS

Sera were collected from the following groups: smallpox-vaccinated individuals with or without latent tuberculosis infection (LTBI), unvaccinated donors, and convalescent individuals after MPXV infection. Supernatant of VV- or MPXV-infected Vero cells were inactivated and used as antigens in ELISA or in Western blot (WB) analyses. An MPXV plaque reduction neutralization test (PRNT) was optimized and performed on study samples. VV- and PPD-specific memory T cells were measured by flow cytometry.

RESULTS

None of the smallpox unvaccinated donors tested positive in ELISA or WB analysis and their sera were unable to neutralize MPXV in vitro. Sera from all the individuals convalescing from an MPXV infection tested positive for anti-VV or MPXV IgG with high titers and showed MPXV in vitro neutralization capacity. Sera from most of the vaccinated individuals showed IgG anti-VV and anti-MPXV at high titers. WB analyses showed that positive sera from vaccinated or convalescent individuals recognized both VV and MPXV antigens. Higher VV-specific IgG titer and specific T cells were observed in LTBI individuals.

CONCLUSIONS

ELISA and WB performed using supernatant of VV- or MPXV-infected cells are suitable to identify individuals vaccinated against smallpox at more than 45 years from immunization and individuals convalescing from a recent MPXV infection. ELISA and WB results show a good correlation with PRNT. Data confirm that a smallpox vaccination induces a long-lasting memory in terms of specific IgG and that antibodies raised against VV may neutralize MPXV in vitro. Finally, higher titers of VV-specific antibodies and higher frequency of VV-specific memory T cells in LTBI individuals suggest a role of polyclonal non-specific activation in the maintenance of immunologic memory.

Oral microbiota signatures associated with viremia and CD4 recovery in treatment-naïve HIV-1-infected patients

PURPOSE

Few reports focused on the role of oral microbiome diversity in HIV infection. We characterized the microbiota-immunity axis in a cohort of treatment-naïve HIV-1-infected patients undergoing antiretroviral therapy (ART) focusing on the oral microbiome (OM) and immunological responsivity.

METHODS

The sequencing of 16S rRNA V3-V4 hypervariable region was performed on salivary samples of 15 healthy control (HC) and 12 HIV+ patients before starting ART and after reaching virological suppression. Then, we correlated the OM composition with serum cytokines and the Short Chain Fatty acids (SCFAs).

RESULTS

The comparison between HIV patients and HC oral microbiota showed differences in the bacterial α-diversity and richness. We documented a negative correlation between oral Prevotella and intestinal valeric acid at before starting ART and a positive correlation between oral Veillonella and gut acetic acid after reaching virological suppression. Finally, an increase in the phylum Proteobacteria was observed comparing saliva samples of immunological responders (IRs) patients against immunological non-responders (INRs).

CONCLUSIONS

For the first time, we described an increase in the oral pro-inflammatory Proteobacteria phylum in INRs compared to IRs. We provided more evidence that saliva could be a non-invasive and less expensive approach for research involving the oral cavity microbiome in HIV patients.

When it rains, it pours: Early treatment with tecovirimat of cardiac complications associated with monkeypox infection in a person with HIV and previously undiagnosed Lyme disease. A case report

Cardiac involvement, such as myocarditis and pericarditis, can be a severe complication of monkeypox virus (mpox) infection and could be related to other co-infections with cardiac involvement. Tecovirimat is an antiviral specifically designed to inhibit smallpox infection diffusion and approved by the FDA for other Orthopoxvirus infections; its efficacy in mpox-infected patients is not well established. We present the case of a cardiac complication during mpox infection in a previously undiagnosed Lyme disease in a 42-year-old man living with HIV. Two days after the typical maculopapular rash, the patient reported a rise in body temperature up to 39 °C, chest pain without irradiation, and shortness of breath. We found an increase in troponin level, a slight reduction in ejection fraction, and grade 2 AV block (Mobitz 1 and 2) with frequent sinus pauses (the longest of 10.1 s). Given the suspicion of myopericarditis with cardiac conduction system involvement, the patient was admitted to the Intermediate Care Unit for continuous monitoring and further evaluation. Treatment included Ibuprofen 600 mg every 12 hours (bid) and colchicine 1 mg once daily for anti-inflammatory purposes. Concomitantly, treatment with tecovirimat was started at 600 mg bid for a total of 14 days. Cardiac MRI with gadolinium showed mild interstitial edema and pericardial enhancement. However, despite the clinical and laboratory resolution of the acute phase, bradycardia with episodes of AV block persisted at follow-up, suggesting the possibility of an additional etiology. Thus, the patient was investigated for Lyme disease because high-degree AV block is the most common presentation of Lyme carditis. Serological results evidenced a previous Borrelia burgdorferi senso latu. We decided to start treatment with doxycycline 100 mg every 12h, even pending the uncertainty of the role of a previous Lyme disease in determining the cardiac rhythm disturbances. At the evaluation on day 44, the patient was systemically well, and after cardiologist consultation, pace-maker implantation was not deemed indicated. This case underscores the importance of considering alternative causes of carditis when the clinical picture remains unclear or persists after the acute phase.

Latent Tuberculosis Infection and COVID-19: Analysis of a Cohort of Patients from Careggi University Hospital (Florence, Italy)

Data regarding the relationship between coronavirus disease (COVID-19) and active or latent tuberculosis (TB) are discordant. We conducted a retrospective study examining the impact of latent tuberculosis infection (LTBI) on the clinical progression of COVID-19 patients. We selected 213 patients admitted with COVID-19 in a tertiary-level Italian hospital (February-December 2020), who underwent a QuantiFERON-TB test (QFT) and/or chest radiological exam. The population was divided into three groups: (i) QFT negative and without radiological TB sequelae (Neg); (ii) QFT positive and without radiological TB sequelae (Pos); (iii) radiological TB sequelae regardless of QFT result (Seq). In-hospital mortality and oro-tracheal intubation (OTI) showed significantly higher results in the Seq group (Seq 50% vs. Pos 13.3% vs. Neg 9.3%, p < 0.001; Seq 16.7% vs. Pos 6.7% vs. Neg 4.9%, p = 0.045). Considering the Pos and Seq groups' patients as the population with defined LTBI, in-hospital mortality (20/51, 39.2%) and OTI risk (7/51, 13.7%) were statistically higher with respect to patients without LTBI (in-hospital mortality: 15/162, 9.3%, p < 0.001; OTI risk: 8/162, 4.9%, p = 0.023), respectively. Multivariate analysis showed that radiological sequelae and the Charlson Comorbidity Index (CCI) were significantly associated with higher mortality rate; despite the higher CCI of Seq population, we cannot exclude the correlation between COVID-19 in-hospital mortality and the presence of radiological TB sequelae.

Bendamustine impairs humoral but not cellular immunity to SARS-CoV-2 vaccination in rituximab-treated B-cell lymphoma-affected patients

Background

Patients with B-cell lymphoma are a fragile category of subjects, particularly exposed to infections and characterized by an impaired vaccination response due to the disease itself and, even more, to the chemotherapy regimen. For this reason, extensive knowledge of the immune response status of these subjects is of fundamental importance to obtain possible indications for a tailored immunization strategy.

Methods

We enrolled two cohorts of patients with B-cell lymphoma under rituximab treatment or 3-24 months after treatment. In all patients, we evaluated both humoral and cellular immunological memory toward SARS-CoV-2, after standard vaccination and upon one booster dose.

Results

We observed no Spike-specific IgG production in patients (n = 25) under anti-CD20 treatment, whereas patients (n = 16) vaccinated after the completion of chemotherapy showed a higher humoral response. Evaluating SARS-CoV-2-specific T-cell response, we found that patients in both cohorts had developed robust cellular immunity after vaccination. Of the 21 patients (51%) that experienced a breakthrough SARS-CoV-2 infection, only six patients developed severe disease. Interestingly, these six patients had all been treated with rituximab plus bendamustine. Notably, we observed that Spike-specific IgG levels in patients treated with rituximab plus bendamustine were absent or lower compared with those in patients treated with rituximab plus other chemotherapy, whereas Spike-specific T-cell response was not different based on chemotherapy regiment.

Discussion

Our results show that, in patients with B-cell lymphoma under rituximab therapy, anti-SARS-CoV-2 mRNA vaccination induces a weak or absent humoral response but a consistent T-cell response. In addition, chemotherapy regimens with bendamustine further reduce patients' ability to mount a Spike-specific humoral response even after a long time period from chemotherapy discontinuation. These results provide evidence that different chemotherapeutics display different immunosuppressive properties that could be taken in to account in the choice of the right drug regimen for the right patient. Moreover, they question whether immunocompromised patients, particularly those treated with bendamustine, need interventions to improve vaccine-induced immune response.

Fourth Dose of mRNA COVID-19 Vaccine Transiently Reactivates Spike-Specific Immunological Memory in People Living with HIV (PLWH)

Background: People Living With HIV (PLWH), with advanced disease, lower CD4+ T cell counts or an unsuppressed HIV viral load can have a suboptimal vaccine response. For this reason, in the current COVID-19 pandemic, they represent a prioritized population for the SARS-CoV-2 fourth (or second booster) vaccine dose. This work aims to investigate the effects of a second booster on the reactivation of the spike-specific humoral and cell-mediated immune responses in PLWH. Methods: A total of eight PLWH, who received a fourth dose of the original mRNA vaccines were enrolled. They were evaluated before and then 7 days, 1 month and 2 months after the injection. The humoral response was assessed via a chemiluminescent immunoassay. Immunophenotyping and the functional evaluation of the SARS-CoV-2-specific cellular immune responses were performed via flow cytometry. Results: Anti-spike IgG levels were above the cut-off value for all subjects at all timepoints. The spike-specific CD4+ T cell response was reactivated one week after the fourth vaccine dose, and on average declined at two months post-vaccination. A similar trend was observed for the spike-specific B cells. A low percentage of spike-specific CD4+ T cells was activated by the B.1.1.529 BA.1 Omicron-spike mutated peptides, and the majority of these cells were reactive to the conserved portions of the spike protein. Similarly, the majority of the spike-specific memory B cells were able to bind both Wuhan and Omicron-spike entire protein. Conclusions: Spike-specific adaptive immune responses are transiently reactivated in PLWH following the fourth mRNA vaccine dose. The breadth of the immune responses to the mutated spike protein provides insight on the possible cross-reactivity for the SARS-CoV-2 variants of concern (VOCs).

Clinical and Immunological Features of SARS-CoV-2 Breakthrough Infections in Vaccinated Individuals Requiring Hospitalization

Background and Purpose

Waning immunity and the surge of SARS-CoV-2 variants are responsible for breakthrough infections, i.e., infections in fully vaccinated individuals. Although the majority of vaccinated infected subjects report mild or no symptoms, some others require hospitalization. The clinical and immunological features of vaccinated hospitalized COVID-19 patients are currently unknown.

Methods

Twenty-nine unvaccinated and 36 vaccinated hospitalized COVID-19 patients were prospectively enrolled and clinical and laboratory data were gathered. Immunophenotyping of leukocytes’ subsets, T and B cell SARS-CoV-2-specific responses were evaluated via flow cytometry. Anti-IFN-α autoantibodies were measured via ELISA.

Results

Despite vaccinated patients were older and with more comorbidities, unvaccinated subjects showed higher levels of pro-inflammatory markers, more severe disease, and increased mortality rate. Accordingly, they presented significant alterations in the circulating leukocyte composition, typical of severe COVID-19. Vaccinated patients displayed higher levels of anti-Spike IgGs and Spike-specific B cells. Of all participants, survivors showed higher levels of anti-Spike IgGs and Spike-specific CD4+ T cells than non-survivors. At hospital admission, 6 out of 65 patients (9.2%) displayed high serum concentrations of autoantibodies targeting IFN-α. Remarkably, 3 were unvaccinated and eventually died, while the other 3 were vaccinated and survived.

Conclusion

Despite more severe pre-existing clinical conditions, vaccinated patients have good outcome. A rapid activation of anti-SARS-CoV-2-specific immunity is fundamental for the resolution of the infection. Therefore, prior immunization through vaccination provides a significant contribution to prevention of disease worsening and can even overcome the presence of high-risk factors (i.e., older age, comorbidities, anti-IFN-α autoantibodies).

Supplementary Information

The online version contains supplementary material available at 10.1007/s10875-022-01325-2.

Effects of viremia and CD4 recovery on gut “microbiome-immunity” axis in treatment-naïve HIV-1-infected patients undergoing antiretroviral therapy

BACKGROUND

Human immunodeficiency virus type 1 (HIV-1) infection is characterized by persistent systemic inflammation and immune activation, even in patients receiving effective antiretroviral therapy (ART). Converging data from many cross-sectional studies suggest that gut microbiota (GM) changes can occur throughout including human immunodeficiency virus (HIV) infection, treated by ART; however, the results are contrasting. For the first time, we compared the fecal microbial composition, serum and fecal microbial metabolites, and serum cytokine profile of treatment-naïve patients before starting ART and after reaching virological suppression, after 24 wk of ART therapy. In addition, we compared the microbiota composition, microbial metabolites, and cytokine profile of patients with CD4/CD8 ratio < 1 (immunological non-responders [INRs]) and CD4/CD8 > 1 (immunological responders [IRs]), after 24 wk of ART therapy.

AIM

To compare for the first time the fecal microbial composition, serum and fecal microbial metabolites, and serum cytokine profile of treatment-naïve patients before starting ART and after reaching virological suppression (HIV RNA < 50 copies/mL) after 24 wk of ART.

METHODS

We enrolled 12 treatment-naïve HIV-infected patients receiving ART (mainly based on integrase inhibitors). Fecal microbiota composition was assessed through next generation sequencing. In addition, a comprehensive analysis of a blood broad-spectrum cytokine panel was performed through a multiplex approach. At the same time, serum free fatty acid (FFA) and fecal short chain fatty acid levels were obtained through gas chromatography-mass spectrometry.

RESULTS

We first compared microbiota signatures, FFA levels, and cytokine profile before starting ART and after reaching virological suppression. Modest alterations were observed in microbiota composition, in particular in the viral suppression condition, we detected an increase of Ruminococcus and Succinivibrio and a decrease of Intestinibacter. Moreover, in the same condition, we also observed augmented levels of serum propionic and butyric acids. Contemporarily, a reduction of serum IP-10 and an increase of IL-8 levels were detected in the viral suppression condition. In addition, the same components were compared between IRs and INRs. Concerning the microflora population, we detected a reduction of Faecalibacterium and an increase of Alistipes in INRs. Simultaneously, fecal isobutyric, isovaleric, and 2-methylbutyric acids were also increased in INRs.

CONCLUSION

Our results provided an additional perspective about the impact of HIV infection, ART, and immune recovery on the “microbiome-immunity axis” at the metabolism level. These factors can act as indicators of the active processes occurring in the gastrointestinal tract. Individuals with HIV-1 infection, before ART and after reaching virological suppression with 24 wk of ART, displayed a microbiota with unchanged overall bacterial diversity; moreover, their systemic inflammatory status seems not to be completely restored. In addition, we confirmed the role of the GM metabolites in immune reconstitution.

Comparison of the efficacy, safety and durability of a switch to co-formulated RPV/TDF-TAF/FTC or DTG/ABC/3TC in virologically-suppressed HIV-1-infected patients in a single Italian centre: a cohort data analysis

This study evaluated the efficacy, safety and durability of a switch to co-formulated RPV/TDF-TAF/FTC (RPV-STR) or DTG/ABC/3TC (DTG-STR) in virologically-suppressed HIV-positive patients in a single Italian centre. All HIV-infected ART-experienced patients switching to RPV-STR or DTG-STR with HIV-RNA <50 copies/mL were included. Outcomes were incidence rate and rate ratios for discontinuation due to all causes (DAC), to adverse events (DAE) and to virological failure (VF) after 4 years of follow-up. We included 402 patients (244 on RPV-STR, 158 on DTG-STR). At Year 4 of follow-up, 124 patients (30.8%) discontinued for any cause (71 on RPV-STR, 53 on DTG-STR). Fifteen patients experienced VF [13 (5.3%) on RPV-STR and 2 (1.3%) on DTG-STR; log-rank, P = 0.4413]. Overall, 46 patients (11.4%) had AEs (23 on RPV-STR, 23 on DTG-STR). Nausea/diarrhoea was more frequent with DTG-STR (4.4% vs. 0%) and neurological toxicity with RPV-STR (4.5% vs. 2.5%). The rate of DAC within the first 3 months was significantly higher with DTG-STR (aRR = 5.88, 95% CI 3.20-10.81; P < 0.001); similarly, the discontinuation rate due to AEs was significantly higher with DTG-STR compared with RPV-STR (aRR = 12.89, 95% CI 5.48-30.32; P < 0.001). No difference in VF was observed between the two groups (RR = 0.47, 95% CI 0.10-2.14; P = 0.335). Patients with undetectable viral load who switched to DTG-STR or RPV-STR maintained virological suppression with a low risk of VF. A higher discontinuation rate was observed with DTG-STR compared with RPV-STR, particularly within 3 months from switch.

First-dose mRNA vaccination is sufficient to reactivate immunological memory to SARS-CoV-2 in subjects who have recovered from COVID-19

The characterization of the adaptive immune response to COVID-19 vaccination in individuals who recovered from SARS-CoV-2 infection may define current and future clinical practice. To determine the effect of the 2-dose BNT162b2 mRNA COVID-19 vaccination schedule in individuals who recovered from COVID-19 (COVID-19-recovered subjects) compared with naive subjects, we evaluated SARS-CoV-2 Spike-specific T and B cell responses, as well as specific IgA, IgG, IgM, and neutralizing antibodies titers in 22 individuals who received the BNT162b2 mRNA COVID-19 vaccine, 11 of whom had a previous history of SARS-CoV-2 infection. Evaluations were performed before vaccination and then weekly until 7 days after second injection. Data obtained clearly showed that one vaccine dose is sufficient to increase both cellular and humoral immune response in COVID-19-recovered subjects without any additional improvement after the second dose. On the contrary, the second dose proved mandatory in naive subjects to further enhance the immune response. These findings were further confirmed at the serological level in a larger cohort of naive (n = 68) and COVID-19-recovered (n = 29) subjects, tested up to 50 days after vaccination. These results question whether a second vaccine injection in COVID-19-recovered subjects is required, and indicate that millions of vaccine doses may be redirected to naive individuals, thus shortening the time to reach herd immunity.

Heterogeneous magnitude of immunological memory to SARS-CoV-2 in recovered individuals

Objective

Although the adaptive immune response to SARS‐CoV‐2 has been characterised in the acute and early convalescent phase of the disease, few studies explore whether natural infection elicits long‐lasting immunological memory in recovered individuals. In this work, we aimed to assess the maintenance of immunological memory to SARS‐CoV‐2.

Methods

We evaluated the long‐term virus‐specific cellular and humoral immune response in the members of an Italian Serie A football team, who experienced a cluster of COVID‐19 in March 2020, which was strictly evaluated in the following months.

Results

Our results highlight a heterogeneous magnitude of immunological memory at 5 months after infection. Indeed, 20% of the subjects displayed a weak cellular and humoral memory to SARS‐CoV‐2, suggesting that they may be at higher risk of reinfection. In addition, a history of symptomatic COVID‐19 was associated with higher levels of SARS‐CoV‐2‐reactive CD4⁺ T cells and specific antibody levels than in asymptomatic individuals.

Conclusion

Collectively, these data demonstrate that immunity to SARS‐CoV‐2 is maintained five months postinfection even if the magnitude of response is heterogeneous among individuals. This finding suggests that some COVID‐19‐recovered subjects may benefit from vaccination.

Long-term maintenance of virologic suppression in native and migrant HIV-1 naïve patients: an Italian cohort study

Little is known about long-term maintenance of virologic suppression in HIV migrants in Italy. The study aims to compare virologic failure rates and associated factors among antiretroviral therapy (ART)-naïve migrants and natives enrolled in the ARCA database since 2007 who achieved virologic suppression within 18 months from the beginning of the ART. Kaplan-Meier method assessed the probability of virologic suppression and failure. Cox regression model was used for multivariate analysis. Of 2515 patients, 2020 (80.3%) were Italian, 286 (10.6%) migrants from low-income countries, of whom 201 (75.0%) from Africa, and 227 (9.0%) from high-income-countries. The median follow-up was 4.5 years (IQR 2.5-7). No difference was observed in the time of achievement of virological suppression in the three groups (log-rank: p = 0.5687). Higher probability of virologic failure was observed in Africans compared to Italians, to patients from high-income-countries and from low-income-countries other than Africans (Log-rank = p < 0.001). In the adjusted analysis, a higher virologic failure risk was found in Africans only compared to Italians. [HR 4.01; 95% CI 2.44-6.56, p < 0.001]. In Italy, African migrants are less likely to maintain virologic suppression compared to natives and other migrants. Targeted interventions could be needed for foreigners, especially for Africans.

Cell-mediated and humoral adaptive immune responses to SARS-CoV-2 are lower in asymptomatic than symptomatic COVID-19 patients

The characterization of cell-mediated and humoral adaptive immune responses to SARS-CoV-2 is fundamental to understand COVID-19 progression and the development of immunological memory to the virus. In this study, we detected T-cells reactive to SARS-CoV-2 proteins M, S, and N, as well as serum virus-specific IgM, IgA, IgG, in nearly all SARS-CoV-2 infected individuals, but not in healthy donors. Virus-reactive T cells exhibited signs of in vivo activation, as suggested by the surface expression of immune-checkpoint molecules PD1 and TIGIT. Of note, we detected antigen-specific adaptive immune response both in asymptomatic and symptomatic SARS-CoV-2 infected subjects. More importantly, symptomatic patients displayed a significantly higher magnitude of both cell-mediated and humoral adaptive immune response to the virus, as compared to asymptomatic individuals. These findings suggest that an uncontrolled adaptive immune response contribute to the development of the life-threatening inflammatory phase of the disease. Finally, this study might open the way to develop effective vaccination strategies.

Evaluation of a new rapid fluorescence immunoassay for the diagnosis of dengue and Zika virus infection

BACKGROUND

Dengue (DENV) and Zika virus (ZIKV) are important mosquito-transmitted viruses.

OBJECTIVES

To investigate the performance of Standard F, Fluorescence Immunoassay (FIA, SD Biosensor Inc., Suwon, South Korea) providing results in 15 min to detect DENV IgG, IgM and NS1Ag, and ZIKV IgG, IgM, and Ag.

STUDY DESIGN

A well-characterized panel of patient samples (11 acute DENV, 11 acute ZIKV, 10 past DENV, 10 past ZIKV infection, 36 with other conditions) were tested with the FIA test.

RESULTS

In acute DENV infection, the combination of FIA-NS1Ag and/or IgM positivity showed a sensitivity of 100%. In past DENV, FIA-IgG test showed a sensitivity of 70%. Specificity of FIA-DENV NS1Ag, IgG, and IgM was 87.5%, 83.5%, and 91.7%, respectively. The sensitivity of FIA-ZIKV IgM and FIA-ZIKV Ag, in confirmed acute infection, was 72.7% and 9.1%, respectively. FIA-ZIKV Ag did not improve the sensitivity in detecting acute ZIKV infection, being positive only in one IgM positive sample. In past ZIKV infection (32-183 days after symptom onset), FIA-ZIKV IgG and IgM showed a sensitivity of 40% and 80% respectively, generating an overall 90% sensitivity. Specificity of FIA-ZIKV Ag, IgM, and IgG was 92.6%, 100%, and 97%, respectively.

CONCLUSION

FIA test, a rapid and easy to perform assay, showed high sensitivity to detect acute DENV infection, but lower in acute ZIKV infection. In past ZIKV infections, the best performance of FIA test is obtained by combining detection of IgG and IgM.

Continuum of care among HIV-1 positive patients in a single center in Italy (2007-2017)

AIM

This study aimed to determine rates of retention in care, viral suppression, and use of antiretroviral therapy (ART) and identify risk factors for loss to follow-up (FU) in an adult cohort from a tertiary teaching hospital in Florence, Italy.

METHODS

We included all newly diagnosed HIV-infected patients aged >18 years who were linked to our clinic from July 2007 to December 2015. On July 31, 2017, we evaluated the proportion of patients retained in care, on ART, and having HIV RNA <50 copies/mL. We assessed predictors of loss to FU through univariate and multivariate analyses.

RESULTS

We included 423 patients. By July 2017, 23 (5.5%) patients died, 25 (5.9%) moved to a different center, and 64 (15.1%) were lost to follow-up. Among the remaining 311 patients (73.5%), 96.5% were on ART and 95% had HIV RNA <50 copies/mL. After adjustment for sex, age at diagnosis, origin, and risk of transmission, our results showed a lower retention rate in those not on ART at the end of the follow-up (adjusted HR [aHR]: 10.33, 95% CI 5.80-18.40, P<0.001), non-Italians (aHR: 1.69, 95% CI: 0.99-2.89, P=0.054) and <35 years old (aHR: 1.85; 95% CI 1.04-3.30, P=0.037).

CONCLUSION

In our hospital in Florence, we found a gap in retention in care among foreigners, people <35 years old, and those who were not in treatment at the end of the follow-up. The results of this study may help to identify opportunities for appropriate future interventions.

Immunoglobulin M indirect-fluorescent antibody test for the diagnosis of acute toxoplasmosis during pregnancy in the avidity era: A 14-year experience at the Tuscany Reference Center for Infectious Diseases in Pregnancy, Florence, Italy

AIM

The aim of this study was to evaluate immunoglobulin M indirect-fluorescent antibody test (IgM IFAT) for the diagnosis of acute or chronic Toxoplasma infection in pregnancy.

METHODS

Pregnant women with suspected acute toxoplasmosis referred to the Tuscany Reference Center for Infectious Diseases in Pregnancy during the period 1998-2012 were retrospectively enrolled. All women were tested with a panel of serological tests, including enzyme-linked immunosorbent assay for IgG avidity and IgM IFAT. On the basis of anamnestic, clinical, and serological criteria, pregnant women were classified into three groups: recently infected (RI), latently infected (LI), and doubtful latently infected (DLI). Patients classified as DLI were excluded from the analysis. The association between IgM IFAT (positive or negative) and the diagnosis of infection (acute or chronic) was assessed. Positive predictive value and negative predictive value of the IgM IFAT were calculated.

RESULTS

A total of 810 pregnant women were enrolled in the study: 302 in the RI group and 508 in the LI group. Fifty-two women classified as DLI were excluded. IgM IFAT was positive in 172 out of 302 (56.9%) pregnant women in the RI group and in 29 out of 508 (5.7%) in the LI group. The positive predictive value and negative predictive value of IgM IFAT in predicting RI was 85.6% and 78.6%, respectively.

CONCLUSION

IgM IFAT has reasonable sensitivity and specificity in diagnosing recent infection and, mostly in case of borderline avidity test, could be considered as a further aid for an accurate diagnosis of acute toxoplasmosis in pregnancy.