Pneumocystis jirovecii pneumonia (PCP) is a life-threatening infection in immunocompromised patients. Quantitative real-time PCR (qPCR) is more sensitive than microscopic examination for the detection of P. jirovecii but also detects colonized patients. Hence, its positive predictive value (PPV) needs evaluation. In this 4-year prospective observational study, all immunocompromised patients with acute respiratory symptoms who were investigated for PCP were included, totaling 659 patients (814 bronchoalveolar lavage fluid samples). Patients with negative microscopy but positive qPCR were classified through medical chart review as having retained PCP, possible PCP, or colonization, and their clinical outcomes were compared to those of patients with microscopically proven PCP. Overall, 119 patients were included for analysis, of whom 35, 41, and 43 were classified as having retained PCP, possible PCP, and colonization, respectively. The 35 patients with retained PCP had clinical findings similar to those with microscopically proven PCP but lower fungal loads (P < 0.001) and were mainly non-HIV-infected patients (P < 0.05). Although the mean amplification threshold was higher in colonized patients, it was not possible to determine a discriminant qPCR cutoff. The PPV of qPCR in patients with negative microscopy were 29.4% and 63.8% when considering retained PCP and retained plus possible PCP, respectively. Patients with possible PCP had a higher mortality rate than patients with retained PCP or colonization (63% versus 3% and 16%, respectively); patients who died had not received co-trimoxazole. In conclusion, qPCR is a useful tool to diagnose PCP in non-HIV patients, and treatment might be better targeted through a multicomponent algorithm including both clinical/radiological parameters and qPCR results.
(1) Background: The diagnosis of invasive aspergillosis (IA) in an intensive care unit (ICU)remains a challenge and the COVID-19 epidemic makes it even harder. Here, we evaluatedAspergillus PCR input to help classifying IA in SARS-CoV-2-infected patients. (2) Methods: 45COVID-19 patients were prospectively monitored twice weekly for Aspergillus markers and anti-Aspergillus serology. We evaluated the concordance between (Ι) Aspergillus PCR and culture inrespiratory samples, and (ΙΙ) blood PCR and serum galactomannan. Patients were classified asputative/proven/colonized using AspICU algorithm and two other methods. (3) Results: Theconcordance of techniques applied on respiratory and blood samples was moderate (kappa = 0.58and kappa = 0.63, respectively), with a higher sensitivity of PCR. According to AspICU, 9/45 patientswere classified as putative IA. When incorporating PCR results, 15 were putative IA because theymet all criteria, probably with a lack of specificity in the context of COVID-19. Using a modifiedAspICU algorithm, eight patients were classified as colonized and seven as putative IA. (4)Conclusion: An appreciation of the fungal burden using PCR and Aspergillus serology was addedto propose a modified AspICU algorithm. This proof of concept seemed relevant, as it was inagreement with the outcome of patients, but will need validation in larger cohorts.
Trichophyton verrucosum is a zoophilic dermatophyte, known as a causative agent of inflammatory mycoses of the skin and the scalp in humans. In this study, we reviewed all cases of T. verrucosum infection diagnosed in our laboratory over a 12-year period, to determine epidemiological and clinical characteristics. Among 18,340 samples analyzed, 5,186 cultured positive with dermatophytes (2674 patients), of which 64 samples (41 patients) were positive for T. verrucosum. Our data show that there was a strong influence of age on the type of lesion, with children and adults presenting more frequently with tinea capitis and skin infections, respectively (P < .0001). Infection of children and adults resulted more frequently from indirect and direct exposure to cattle, respectively (P < .01). We observed a marked increase of cases over the last 4 years, with a correlation of the number of cases and the mean annual rainfall (P < .05), suggesting that increasing humidity favors cattle infection, and thereby, human infection. Whether this increase is the consequence of climate changes remains to be determined but should be considered.
The molecular detection of Aspergillus directly in BAL samples greatly improved the diagnosis of IA, particularly in non-hematological patients.
Invasive pulmonary aspergillosis (IPA) in intensive care unit patients is a major concern. Influenza-associated acute respiratory distress syndrome (ARDS) and severe COVID-19 patients are both at risk of developing invasive fungal diseases. We used the new international definitions of influenza-associated pulmonary aspergillosis (IAPA) and COVID-19-associated pulmonary aspergillosis (CAPA) to compare the demographic, clinical, biological, and radiological aspects of IAPA and CAPA in a monocentric retrospective study. A total of 120 patients were included, 71 with influenza and 49 with COVID-19-associated ARDS. Among them, 27 fulfilled the newly published criteria of IPA: 17/71 IAPA (23.9%) and 10/49 CAPA (20.4%). Kaplan–Meier curves showed significantly higher 90-day mortality for IPA patients overall (p = 0.032), whereas mortality did not differ between CAPA and IAPA patients. Radiological findings showed differences between IAPA and CAPA, with a higher proportion of features suggestive of IPA during IAPA. Lastly, a wide proportion of IPA patients had low plasma voriconazole concentrations with a higher delay to reach concentrations > 2 mg/L in CAPA vs. IAPA patients (p = 0.045). Severe COVID-19 and influenza patients appeared very similar in terms of prevalence of IPA and outcome. The dramatic consequences on the patients’ prognosis emphasize the need for a better awareness in these particular populations.
bThis study aimed to evaluate the repeated sequence REP-529 compared to that of the B1 gene in the molecular diagnosis of toxoplasmosis by quantitative PCR (qPCR) in routine diagnosis. Over a 10-year period (2003 to 2013), all patients prospectively diagnosed with a positive REP-529 qPCR result for toxoplasmosis were included. All DNA samples (76 samples from 56 patients) were simultaneously tested using the two qPCR methods (REP-529 and B1). The mean cycle threshold (C T ) obtained with the B1 qPCR was significantly higher (؉4.71 cycles) than that obtained with REP-529 qPCR (P < 0.0001). Thirty-one out of 69 extracts (45.6%) positive with REP-529 qPCR were not amplified with the B1 qPCR (relative sensitivity of 54.4% compared to that with REP-529), yielding false-negative results with 15/28 placenta, 5 cord blood, 2 amniotic fluid, 4 cerebrospinal fluid, 1 aqueous humor, 2 lymph node puncture, and 1 abortion product sample. This defect in sensitivity would have left 20/56 patients undiagnosed, distributed as follows: 12/40 congenital toxoplasmosis, 4/5 cerebral toxoplasmosis, 2/8 patients with retinochoroiditis, and 2 patients with chronic lymphadenopathy. This poor performance of B1 qPCR might be related to low parasite loads, since the mean Toxoplasma quantification in extracts with B1 false-negative results was 0.4 parasite/reaction. These results clearly show the superiority of the REP-529 sequence in the diagnosis of toxoplasmosis by PCR and suggest that this target should be adopted as part of the standardization of the PCR assay.T oxoplasmosis is a worldwide parasitic infection due to the intracellular parasite Toxoplasma gondii. The infection is usually asymptomatic in immunocompetent patients and more rarely results in fever, lymphadenopathy, or retinochoroiditis. In contrast, immunocompromised patients can experience severe neurologic, ocular, pulmonary, or disseminated disease (1). Yet, toxoplasmosis is well known for its pathogenicity during pregnancy. Indeed, when primary infection occurs in pregnant women, it can lead to congenital toxoplasmosis, with a frequency of transmission and a severity of fetal infection depending on the stage of pregnancy at which infection occurs (2). The diagnosis of toxoplasmosis is routinely based on serology. In some countries, such as France, seronegative pregnant women are monitored monthly by serology. In case of seroconversion, the detection of T. gondii DNA by PCR is a major diagnostic method for congenital toxoplasmosis and is performed on amniotic fluid (prenatal diagnosis) (3-5) and placenta or cord blood samples at birth (postnatal diagnosis) (6-8). In immunocompromised patients, DNA can also be found in cerebrospinal fluid (CSF), bronchoalveolar lavage (BAL) fluid, or other samples, as guided by clinical signs. The 35-fold repeated B1 gene (9) has commonly been used for this molecular diagnosis since 1989, with acceptable sensitivity (3, 5, 10), but another sequence (REP-529, GenBank accession no. AF146527) was described more recently as being repeated 200 ...
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