Challenges remain in the diagnosis of invasive aspergillosis. In this report, the potential for diet to affect the interpretation of the galactomannan assay is presented.
To the Editor:
A 42-year-old ...woman received an HLA-matched hematopoietic stem-cell transplant from an unrelated donor for a myeloproliferative syndrome. Serum aspergillus antigen (galactomannan) (Bio-Rad Laboratories) was assessed twice weekly from the day of transplantation and remained negative (index, <0.5) until 30 days after transplantation. The index increased to 2.22 and 3.01 on days 32 and 34, respectively. At that time, the patient had severe gastrointestinal graft-versus-host disease (GVHD). She was afebrile with no pulmonary or sinus symptoms. Computed tomographic (CT) scans of the lung, brain, and sinus were normal, and a CT scan of the abdomen showed no evidence . . .
Background. Invasive wound mucormycosis (IWM) is associated with an extremely poor outcome among critically ill burn patients. We describe the detection of circulating Mucorales DNA (cmDNA) for the ...early diagnosis of IWM in those patients and report the potential value of detecting cmDNA for treatment guidance. Methods. Severely ill burn patients admitted to our tertiary referral center between October 2013 and February 2016 were included. Retrospective plasma samples were tested for the presence of cmDNA by quantitative real-time polymerase chain reaction (qPCR). Patients were then prospectively screened twice a week, and liposomal amphotericin-B therapy initiated based on a positive qPCR. The primary endpoint was the time between cmDNA detection and standard diagnosis. Secondary endpoints were the time from cmDNA detection and treatment initiation and mortality. Results. Seventy-seven patients (418 samples) were included. The average age was 46 (28–60) years, abbreviated burn severity index was 8 (7–10), and simplified acute physiology score was 33 (23–46). The total body surface area was 33% (22%–52%). cmDNA was detected 11 (4.5–15) days before standard diagnosis. The in-hospital mortality was 62% for patients with IWM and 24% for those without (P = .03). The mortality due to IWM was 80% during period A and 33% during period B (P = .46). Conclusions. This study suggests that the detection of cmDNA allows earlier diagnosis of IWM in severely ill burn patients and earlier initiation of treatment. Further studies are needed to confirm the impact of earlier treatment initiation on patient outcome.
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BFBNIB, NUK, PNG, UL, UM, UPUK
Globally distributed with variable prevalence depending on geography, toxoplasmosis is a zoonosis caused by an obligate intracellular protozoan parasite, Toxoplasma gondii. This disease is usually ...benign but poses a risk for immunocompromised people and for newborns of mothers with a primary infection during pregnancy because of the risk of congenital toxoplasmosis (CT). CT can cause severe damage to fetuses-newborns. To our knowledge, no study has been conducted in sub-Saharan Africa on toxoplasmosis seroprevalence, seroconversion and CT in a large longitudinal cohort and furthermore, no observation has been made of potential relationships with malaria.
We performed a retrospective toxoplasmosis serological study using available samples from a large cohort of 1,037 pregnant women who were enrolled in a malaria follow-up during the 2008-2010 period in a rural area in Benin. We also used some existing data to investigate potential relationships between the maternal toxoplasmosis serological status and recorded malaria infections.
Toxoplasmosis seroprevalence, seroconversion and CT rates were 52.6%, 3.4% and 0.2%, respectively, reflecting the population situation of toxoplasmosis, without targeted medical intervention. The education level influences the toxoplasmosis serological status of women, with women with little or no formal education have greater immunity than others. Surprisingly, toxoplasmosis seropositive pregnant women tended to present lower malaria infection during pregnancy (number) or at delivery (presence) and to have lower IgG levels to Plasmodium falciparum Apical Membrane Antigen 1, compared to toxoplasmosis seronegative women.
The high toxoplasmosis seroprevalence indicates that prevention against this parasite remains important to deploy and must be accessible and understandable to and for all individuals (educated and non-educated). A potential protective role against malaria conferred by a preexisting toxoplasmosis infection needs to be explored more precisely to examine the environmental, parasitic and/or immune aspects.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
BACKGROUND:A high incidence of acute hepatitis C virus (HCV) (AHCV) infection has been reported among at-risk HIV-negative MSM. The optimal strategy for early diagnosis of AHCV in this population is ...not clearly defined.
METHODS:In the ANRS IPERGAY PrEP trial, among high-risk HIV-negative MSM, HCV serology and serum alanine aminotransferase (ALT) were used for screening at enrollment and during follow-up. Behavioral risk factors were compared at baseline between participants who were diagnosed with AHCV during the study compared with those who did not. In participants with a positive HCV serology, we used stored sera to perform the following tests at diagnosis and on previous visitsHCV-antibodies rapid tests, plasma HCV viral load and HCV antigen immunoassay. We evaluated the sensitivity of each test for AHCV diagnosis.
RESULTS:Among 429 enrolled participants, 14 were diagnosed with AHCV infection, with a median follow-up of 2.1 (interquartile range, 1.5–2.8) years. AHCV incidence was 1.40 per 100 person-years (95% confidence interval, 0.74–2.39). Patients with AHCV reported a significantly higher number of sexual acts and/or partners, and more frequent recreational drug use at baseline. At the prior visit before AHCV diagnosis (median of 2 months earlier), sensitivities of HCV RNA and HCV antigen tests were, respectively, 100 and 89%, whereas none of the patients had a positive serology, and only 25% had elevated ALT.
CONCLUSION:HCV antigen and RNA tests were positive within a median of 2 months before the detection of antibodies and ALT elevation. These tests could be considered for HCV screening in high-risk MSM.
Droplet digital PCR (ddPCR) after DNA digestion yielded a 28S rDNA copy number of 61 to 86 copies/genome when testing 10 unrelated Aspergillus fumigatus isolates, higher than with quantitative PCR. ...Unfortunately, ddPCR after DNA digestion did not improve the sensitivity of our PCR assay when testing serum patients with invasive aspergillosis.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The protozoan
presents a risk for reactivation of latent cysts in immunocompromised patients. Anti-
antibodies are therefore usually screened before chemotherapy or transplantation to propose ...prophylactic measures against this parasite. We analyzed the results obtained in our hospital to study the epidemiological trend of
infection.
We collected all the anti-
antibody titers from January 1, 1997 to December 31, 2013 using the Platelia IgG ELISA assay (Bio-Rad). The results were classified as positive when titers reached a concentration of ≥10 UI/ml. Only the first result obtained at entry for each patient was considered.
seroprevalence was estimated using a multivariate logistic regression model accounting for age, sex, and year in which the sample was collected.
A total of 21,480 patient samples were analyzed. The seroprevalence continuously decreased over time, from 64.5% in 1997 to 54.7% in 2013 (i.e., an average of 1.3% per year,
< 0.001). The decrease was 5.0% per year for patients <20 years. After 2013, the model predicts that the seroprevalence would continuously decrease. We also observed a higher proportion of seropositive men than women in the 15- to 45-year-old group (58.5% versus 52.0%,
< 10
).
The overall seroprevalence of toxoplasmosis at our hospital showed an accelerating downward trend over 17 years. The reason for this continuous decline is likely associated with the lower parasite presence within meat. Thus, although young immunocompromised patients are increasingly less at risk of reactivation in the near future, older immunocompromised patients will remain at high risk of reactivation. The reasons of the higher prevalence in men remain to be explored.
Pneumocystis pneumonia is a severe opportunistic infection in immunocompromised patients caused by the unusual fungus Pneumocystis jirovecii. Transmission is airborne, with both immunocompromised and ...immunocompetent individuals acting as a reservoir for the fungus. Numerous reports of outbreaks in renal transplant units demonstrate the need for valid genotyping methods to detect transmission of a given genotype. Here, we developed a short tandem repeat (STR)-based molecular typing method for P. jirovecii. We analyzed the P. jirovecii genome and selected six genomic STR markers located on different contigs of the genome. We then tested these markers in 106 P. jirovecii PCR-positive respiratory samples collected between October 2010 and November 2013 from 91 patients with various underlying medical conditions. Unique (one allele per marker) and multiple (more than one allele per marker) genotypes were observed in 34 (32%) and 72 (68%) samples, respectively. A genotype could be assigned to 55 samples (54 patients) and 61 different genotypes were identified in total with a discriminatory power of 0.992. Analysis of the allelic distribution of the six markers and minimum spanning tree analysis of the 61 genotypes identified a specific genotype (Gt21) in our hospital, which may have been transmitted between 10 patients including six renal transplant recipients. Our STR-based molecular typing method is a quick, cheap and reliable approach to genotype Pneumocystis jirovecii in hospital settings and is sensitive enough to detect minor genotypes, thus enabling the study of the transmission and pathophysiology of Pneumocystis pneumonia.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The Platelia Aspergillus Ag assay (Bio-Rad) is designed for detecting Aspergillus galactomannan (GM) and is widely used for diagnosing invasive aspergillosis but is hampered by variable occurrences ...of unreproducible positive results. Frequency and origin of these unreproducible results have not been formally studied.
Different technicians simultaneously performed four tests on 550 consecutive sera from adult patients (Test#1-Test#2 for extraction#1 and Test#3-Test#4 for extraction#2). The samples were classified as confirmed negative all tests with GM optical density index (GM-ODI) <0.5, confirmed positive (all tests with GM-ODI ≥0.5), extraction unreproducible positive (Test#1 and Test#2 ODIs ≥0.5, and Test#3 and Test#4 GM-ODIs <0.5, or conversely), and ELISA unreproducible positive (only one test with GM-ODI ≥0.5). The samples with positive and negative GM-ODIs within the assay coefficient of variation values were classified as non-conclusive. Four similar additional tests were performed after ≤72h storage at 4 °C and a new GM test after 8 months at -20 °C.
Five-hundred-twenty sera (94.5%) were confirmed negative, 15 (2.7%) confirmed positive, 4 (0.7%) extraction unreproducible positive, 6 (1.1%) ELISA unreproducible positive, and 5 (0.9%) non-conclusive. Upon retesting, the unreproducible positive results turned negative except for one which turned non-conclusive. The confirmed positive and non-conclusive had similar GM-ODIs (p>0.4) upon retesting after storage ≤72h at 4 °C (n = 20) or eight months at -20 °C (n = 17).
Operational unreproducible positives represent 33% of the GM-positive results and a second sample evaluation appears mandatory to avoid useless investigations or treatments. When operational artifacts are excluded, GM remains stable at standard storage conditions.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Primary Sjögren's syndrome (pSS) is characterized by B cell hyperactivation, production of autoantibodies and increased risk of B cell lymphomas. Serological profile of Epstein-Barr virus (EBV) ...reactivation and increase EBV DNA levels in exocrine glands are observed in pSS, but whether these abnormalities are accompanied with disturbed systemic EBV control or have any association with pSS activity remains to be investigated. In this observational study, we initially explored anti-EBV antibodies and cell-free DNA in 395 samples from a cross-sectional plasma collection of pSS patients included in ASSESS French national cohort. Results were assessed in relation with disease activity. Further, to assess cell-associated EBV DNA we organized a case-control study including 20 blood samples from pSS patients followed in University Hospital Center of Montpellier. Results were compared with matched controls. Robust response against EBV early antigen (EA) was observed in pSS patients with anti-SSA/B (Sjögren's syndrome A and B) and anti-SSA autoantibodies compared to anti-SSA/B negatives (
< 0.01 and
= 0.01, respectively). Increased beta-2 microglobulin, kappa and lambda light chains, and immunoglobulin G levels were more frequently observed in anti-EA seropositive pSS subjects compared to anti-EA negative subjects (
< 0.001;
= 0.001;
= 0.003, respectively). Beta-2 microglobulin was independently associated with anti-EA positivity in multivariate analysis (
< 0.001). Plasma cell-free EBV DNA and EBV cellular reservoir was not different between pSS patients and controls. We conclude that serological evidence of EBV reactivation was more frequently observed and more strongly associated with anti-SSA/B status and B cell activation markers in pSS. However, serological profile of EBV reactivation was not accompanied by molecular evidence of systemic EBV reactivation. Our data indicated that EBV infection remains efficiently controlled in the blood of pSS patients.
The performance of antigen galactomannan (GM) for diagnosing invasive aspergillosis (IA) is hampered by the occurrence of false-positive results. Quantitative PCR has been proposed to improve the ...diagnosis of IA. Therefore, we analyzed the value of performing a PCR test to the GM-positive serum sample. Using a quantitative PCR assay specific for
28S ribosomal DNA, we retrospectively tested 422 GM-positive (Platelia Bio-Rad kit) serum samples collected over 1 year from 147 patients. The cases were classified based on EORTC criteria as "proven," "probable," and "no-IA" before availability of the PCR results. After exclusion of 65 samples for non-reproducibility of GM positivity (
= 62) or PCR inhibition (
= 3), 75 (21.0%) of the remaining 357 samples were PCR-positive. GM and fungal DNA showed a significantly positive correlation (
< 0.0001,
= 0.27, slope = 0.98 ± 0.19). At least one PCR-positive result was observed in 63.3% (31/49) of IA patients and in 13.2% (13/98) of non-IA patients (
< 0.0001). The PCR positivity was also associated with the presence of other microbiological criteria among the 44 patients with IA and complete mycological workup (
= 0.014), as well as a higher mortality rate at six months among the 135 patients with hematological conditions (
= 0.0198). Overall, we found a quantitative correlation between serum GM and circulating DNA with an increased likelihood of IA when both were positive. A PCR-positive result also supported a higher fungal load when GM was already positive. We advocate adding a PCR test for every confirmed GM-positive serum sample.
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