ABSTRACT
Toxoplasmosis, a benign infection, is asymptomatic or paucisymptomatic in over 80% of cases, except in immunocompetent patients suffering from ocular toxoplasmosis or in immunocompromised patients with opportunistic or congenital toxoplasmosis. Diagnosis is based mainly on serology testing. Thus, we compared the performance of the nine most commonly used commercial automated or semiautomated immunoassays for IgG and IgM Toxoplasma gondii antibody detection, that is, the Advia Centaur, Architect, AxSYM, Elecsys, Enzygnost, Liaison, Platelia, VIDAS, and VIDIA assays. The assays were conducted on four panels of serum samples derived during routine testing from patients with an interfering disease and who exhibited a low IgG antibody level in one of two clinical settings, namely, acute or chronic toxoplasmosis. As a result, IgG sensitivities ranged from 97.1% to 100%, and IgG specificities ranged from 99.5% to 100%. For IgG quantification, strong differences in IgG titers (expressed in IU/ml) were noted depending on the assay used. IgM sensitivities ranged from 65% to 97.9%, and IgM specificities ranged from 92.6% to 100%. For defining the best serological strategies to be implemented, it appears crucial to compare the diagnostic performance of the different tests with respect to their specificity and sensitivity in detecting the presence of IgG and IgM antibodies.
Subject(s)
Antibodies, Protozoan/blood , Immunoglobulin G/blood , Immunoglobulin M/blood , Toxoplasma/immunology , Toxoplasma/isolation & purification , Toxoplasmosis/diagnosis , Automation, Laboratory/methods , Humans , Immunoassay/methods , Immunocompromised Host , Sensitivity and Specificity , Toxoplasmosis/parasitologyABSTRACT
Classically, Toxoplasma infection is associated with high levels of specific IgM antibody and a rise in specific IgG levels 1 to 3 weeks later. Atypical IgG seroconversion, without IgM detection or with transient IgM levels, has been described during serologic follow-up of seronegative pregnant women and raises difficulties in interpreting the results. To evaluate the frequency and the characteristics of these atypical cases of seroconversion, an investigation was conducted within the French National Reference Center for Toxoplasmosis, from which 26 cases collected from 12 laboratories belonging to the network were identified. The aim of this work was to retrospectively analyze the results of serologic testing, the treatments administered, and the results of prenatal and postnatal follow-up for these women. In each case, IgG antibodies were detected using both screening and confirmatory tests. IgM antibodies were not detected in 15 cases, and the levels were equivocal or low-positive in 11 cases. The IgG avidity results were low in 16 cases and high in one case. Most of the pregnant women (22/26) were treated with spiramycin from the time that IgG antibodies appeared until delivery. Amniotic fluid was analyzed for Toxoplasma gondii DNA by PCR in 11/26 cases, and the results were negative in all cases. Congenital toxoplasmosis was ruled out in 12/26 newborns. There was no abnormality observed at birth for 10 newborns and no information available for 4 newborns. In conclusion, when the interpretation of serological results is so difficult, it seems cautious to initiate treatment by spiramycin and to follow the pregnant women and their newborns.
Subject(s)
Antibodies, Protozoan/blood , Immunoglobulin M/blood , Pregnancy Complications, Infectious/immunology , Toxoplasma/immunology , Toxoplasmosis/immunology , Antiprotozoal Agents/therapeutic use , Female , France , Humans , Immunoglobulin G/blood , Infant, Newborn , Pregnancy , Pregnancy Complications, Infectious/diagnosis , Pregnancy Complications, Infectious/drug therapy , Pregnant Women , Retrospective Studies , Spiramycin/therapeutic use , Toxoplasmosis/diagnosis , Toxoplasmosis/drug therapyABSTRACT
OBJECTIVE: To evaluate diagnostic and therapeutic practices and then establish a consensus on the management of ocular toxoplasmosis in France through a Delphi study. MATERIALS AND METHODS: Twenty-three French experts in ocular toxoplasmosis were invited to respond to a modified Delphi study conducted online, in the form of two questionnaires, in an attempt to establish a consensus on the diagnosis and management of this pathology. The threshold for identical responses to reach consensus was set at 70 %. RESULTS: The responses of 19 experts out of the 23 selected were obtained on the first questionnaire and 16 experts on the second. The main elements agreed upon by the experts were to treat patients with a decrease in visual acuity or an infectious focus within the posterior pole, to treat peripheral lesions only in the presence of significant inflammation, the prescription of first-line treatment with pyrimethamine-azithromycin, the use of corticosteroid therapy after a period of 24 to 48hours, the prophylaxis of frequent recurrences (more than 2 episodes per year) with trimethoprim-sulfamethoxazole as well as the implementation of prophylactic treatment of recurrences in immunocompromised patients. On the other hand, no consensus emerged with regard to the examinations to be carried out for the etiological diagnosis (anterior chamber paracentesis, fluorescein angiography, serology, etc.), second-line treatment (in the case of failure of first-line treatment), or treatment of peripheral foci. CONCLUSION: This study lays the foundations for possible randomized scientific studies to be conducted to clarify the management of ocular toxoplasmosis, on the one hand to confirm consensual clinical practices and on the other hand to guide practices for which no formal consensus has been demonstrated.
Subject(s)
Toxoplasmosis, Ocular , Azithromycin/therapeutic use , Delphi Technique , Humans , Recurrence , Toxoplasmosis, Ocular/diagnosis , Toxoplasmosis, Ocular/epidemiology , Toxoplasmosis, Ocular/therapy , Trimethoprim, Sulfamethoxazole Drug Combination/therapeutic useABSTRACT
We report the case of a first trimester toxoplasmosis infection in a renal transplant recipient. Real-time polymerase chain reaction in amniotic fluid at 18 weeks was negative for Toxoplasma gondii but at 26 weeks major fetal hydrocephalus was discovered leading to medical termination of pregnancy. Pathological examination confirmed lesions consistent with congenital toxoplasmosis. The herein case report, as well as data from the French reference centre for congenital Toxoplamosis (1835 cases in the past eight years), suggests that the strategy of management of pregnancy's first trimester Toxoplasmosis infection in patients treated by immunosuppressive therapy needs to be reconsidered.
Subject(s)
Toxoplasmosis, Congenital/diagnosis , Transplant Recipients , Adult , Amniotic Fluid/parasitology , DNA, Protozoan/genetics , Female , Humans , Kidney Transplantation , Pregnancy , Pregnancy Trimester, First , Prenatal Diagnosis , Real-Time Polymerase Chain ReactionABSTRACT
Toxoplasmosis manifests no clinical signs in 80% of cases in immunocompetent patient, causing immunization characterized by the persistence of cysts, particularly in brain, muscles, and retina. Assessing the serological status, based on testing for serum toxoplasma IgG and IgM antibodies, is essential in cases that are increasingly at risk for the more severe disease forms, such as congenital or ocular toxoplasmosis. This disease also exposes immunosuppressed patients to reactivation, which can lead to more widespread forms and increased mortality. By interpreting the serological results, we can estimate the risk of contamination or reactivation and define appropriate prophylactic and preventive measures, such as hygienic and dietetic, therapeutic, biological, and clinical follow-up, according to the clinical context. We hereby propose practical approaches based on serological data, resulting from a consensus of a group of experts from the French National Reference Center Network for Toxoplasmosis, according to both routine and specific clinical situations.
Subject(s)
Serologic Tests/methods , Toxoplasmosis/diagnosis , Antibodies, Protozoan/blood , France , Humans , Immunoglobulin G/blood , Immunoglobulin M/bloodABSTRACT
We report an isolated case of toxoplasma pneumonitis in a 27-year-old man. This acute infection occurred after induction chemotherapy for AMLo relapsing 3 years post-allogeneic BMT. The detection of Toxoplasma gondii in the bronchoalvolar lavage (BAL), by culture in fibroblast cell line MRC5 enabled us to make the diagnosis. Pyrimethamine and sulfadiazine were effective.
Subject(s)
Bone Marrow Transplantation/adverse effects , Lung Diseases, Parasitic/transmission , Toxoplasmosis/transmission , Transfusion Reaction , Acute Disease , Adult , Animals , Antibodies, Protozoan/blood , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Antiprotozoal Agents/therapeutic use , Blood Donors , Bronchoalveolar Lavage Fluid/parasitology , Combined Modality Therapy , Humans , Immunocompromised Host , Immunoglobulin G/blood , Immunoglobulin G/immunology , Immunoglobulin M/blood , Immunoglobulin M/immunology , Leukemia, Myeloid/complications , Leukemia, Myeloid/drug therapy , Leukemia, Myeloid/therapy , Lung Diseases, Parasitic/immunology , Male , Mice , Neoplasm Recurrence, Local , Pyrimethamine/therapeutic use , Retreatment , Sulfadiazine/therapeutic use , Tissue Donors , Toxoplasma/immunology , Toxoplasmosis/drug therapy , Toxoplasmosis/immunology , Transplantation, Homologous/adverse effectsABSTRACT
Low antibody titers (3 to 6 IU/mL) detected by IMx and AxSYM Toxo IgG assays in serum samples from 264 pregnant women were confirmed by the dye test and a high-sensitivity agglutination test in, respectively, 98.5% and 95.6% of cases, attesting a premunition of these patients.
Subject(s)
Antibodies, Protozoan/blood , Immunoglobulin G/blood , Pregnancy Complications, Parasitic/diagnosis , Pregnancy Trimester, First/blood , Toxoplasma/isolation & purification , Toxoplasmosis/diagnosis , Animals , Female , Humans , Immunoenzyme Techniques , Pregnancy , Pregnancy Complications, Parasitic/immunology , Pregnancy Trimester, First/immunology , Prospective Studies , Reagent Kits, Diagnostic , Sensitivity and Specificity , Toxoplasma/immunology , Toxoplasmosis/immunologyABSTRACT
INTRODUCTION: Pustular candidiasis in heroin addicts is a rare entity in dermatology. We report a case. CASE REPORT: A 29-year-old female heroin addict developed a painful pustular growth on the scalp. There was no fever. Multiple follicular pustulae measuring 2 to 3 mm were associated with hyperesthesia of the scalp and painful cervical nodes. Biopsy showed acute ostiofolliculitis with a few blastospores and mycelial filaments. Candida albicans was isolated from the pustulae and the buccal cavity. Candida serology was positive (indirect immunofluorescence 1/100, coelectrosyneresis: 4 archs). Search for other localizations and HIV serology were negative. The last injection of brown heroin had been taken 15 days earlier; lemon had been added. Treatment with flucanazole (400 mg/d) led to improvement within 48 hours. DISCUSSION: Sudden development of pustulae or nodules in pilous zones in a heroin addict should suggest the diagnosis. Outcome depends on early treatment after diagnosis and search for other localizations. Our case presented two particular aspects: ostiofollicular localization of the pustulae and a long delay (15 days) between the (presumably) last injection and the development of the lesion. Folliculitis develops almost exclusively in addicts who use brown heroin. Contamination by Candida albicans results from the lemon used to improve solubility at injection.
Subject(s)
Candidiasis, Cutaneous/etiology , Heroin Dependence/complications , Skin Diseases, Vesiculobullous/etiology , Adult , Candidiasis, Cutaneous/pathology , Female , Humans , Scalp Dermatoses/etiology , Scalp Dermatoses/pathology , Skin Diseases, Vesiculobullous/pathologyABSTRACT
Toxoplasma infection in pregnant women may cause congenital toxoplasmosis. Diagnosis of infection is based on serological tests aimed at detecting IgM and IgG antibodies against Toxoplasma gondii. However, IgM antibodies are not an accurate marker for discriminating between acute and latent infection. Detection of residual or persistent IgM may occur months or even years after primary infection, while the IgG avidity test is a rapid means of identifying latent infections in pregnant women who exhibit both IgG and IgM anti-Toxoplasma antibodies on initial testing during pregnancy. In this study, we assessed and compared the performances of four commercially available Toxoplasma IgG avidity tests in immunocompetent and immunocompromised patients with acute and latent toxoplasmosis. The positive predictive value of high avidity to confirm latent toxoplasmosis was 100% for all the assays, indicating that high avidity is a hallmark of latent infection. However, the negative predictive value of high avidity ranged from 99.2% (bioMérieux) to 95.3% (Abbott), indicating that acute toxoplasmosis could not be reliably diagnosed based on low IgG avidity alone. Thus, the avidity test provides a rapid means for identifying latent Toxoplasma infection in immunocompetent pregnant women presenting both IgG and IgM anti-Toxoplasma antibodies on initial testing. In terms of cost-effectiveness, avidity testing is a powerful tool that optimizes screening and follow-up of pregnant women while minimizing the costs of screening by avoiding subsequent costly maternal and fetal investigation and unnecessary treatment. The cheapest assay, Vidas Toxo IgG Avidity, also had the best performance for the diagnosis of latent toxoplasmosis.
Subject(s)
Antibodies, Protozoan/blood , Antibody Affinity/immunology , Reagent Kits, Diagnostic/economics , Toxoplasma/immunology , Toxoplasmosis/diagnosis , Antibodies, Protozoan/analysis , Female , Humans , Immunoglobulin G/blood , Immunoglobulin M/blood , Pregnancy , Toxoplasmosis/bloodSubject(s)
Immunoglobulin M/blood , Pregnancy Complications, Infectious/parasitology , Toxoplasmosis/immunology , Female , Humans , Pregnancy , Pregnancy Complications , Pregnancy Complications, Infectious/blood , Pregnancy Complications, Infectious/immunology , Protozoan Infections/blood , Protozoan Infections/diagnosis , Protozoan Infections/immunology , Reproducibility of Results , Toxoplasmosis/blood , Toxoplasmosis/diagnosisSubject(s)
Aspergillosis/epidemiology , Aspergillus/isolation & purification , Cystic Fibrosis/microbiology , Environmental Microbiology , Lung Diseases, Fungal/epidemiology , Lung Diseases, Fungal/microbiology , Aspergillosis/complications , Community-Acquired Infections/epidemiology , Community-Acquired Infections/microbiology , Cross Infection/epidemiology , Cross Infection/microbiology , Cystic Fibrosis/complications , Humans , Lung Diseases, Fungal/complicationsABSTRACT
The authors report six cases of toenail onyxis due to an unusual yeast species, Candida ciferrii. For half of these cases, direct microscopical examination showed the presence of blastospores and pseudo-to-true mycelium, demonstrating the parasitic transition of the fungus. In light of the literature and of their own experience, the authors suggest that C. ciferrii could be an etiological agent of onychomycosis, particularly for elderly patients with extensive trophic disorders.
Subject(s)
Candida/isolation & purification , Candidiasis/microbiology , Onychomycosis/microbiology , Aged , Aged, 80 and over , Candida/growth & development , Foot Dermatoses/microbiology , Humans , Male , Middle AgedABSTRACT
An extracellular proteinase produced by the filamentous fungus Scedosporium apiospermum has been purified and characterized. Initially, in vitro conditions for enzyme synthesis were investigated. The highest yield of enzyme production was obtained when the fungus was cultivated in modified Czapek-Dox liquid medium supplemented with 0.1% bacteriological peptone and 1% (w/v) glucose as the nitrogen and carbon sources respectively. Purification to homogeneity of the proteinase was accomplished by (NH4)2SO4 precipitation, followed by gel filtration through Sephadex G-75 and finally affinity chromatography through immobilized phenylalanine. Analysis of the purified enzyme by SDS/PAGE revealed a single polypeptide chain with an apparent molecular mass of 33 kDa. Further investigation of its physical and biochemical properties disclosed numerous similarities with those of the previously described serine proteinase of Aspergillus fumigatus. The enzyme was not glycosylated and its pI was 9.3. Proteinase activity was optimum between 37 and 50 degrees C and at pH 9.0, but remained high within a large range of pH values between 7 and 11. The inhibition profile and N-terminal amino acid sequencing confirmed that this enzyme belongs to the subtilisin family of serine proteinases. In agreement with this, the specific synthetic substrate N-succinyl-Ala-Ala-Pro-Phe-p-nitroanilide proved to be an excellent substrate for the proteinase with an estimated Km of 0.35 mM. Like the alkaline proteinase of A. fumigatus, this enzyme was able to degrade human fibrinogen, and thus may act as a mediator of the severe chronic bronchopulmonary inflammation from which cystic fibrosis patients suffer.
Subject(s)
Fungal Proteins/metabolism , Pseudallescheria/enzymology , Serine Endopeptidases/metabolism , Amino Acid Sequence , Aspergillus fumigatus/enzymology , Enzyme Stability , Fungal Proteins/chemistry , Fungal Proteins/isolation & purification , Humans , Hydrogen-Ion Concentration , Isoelectric Point , Molecular Sequence Data , Molecular Weight , Sequence Homology, Amino Acid , Serine Endopeptidases/chemistry , Serine Endopeptidases/isolation & purification , Substrate Specificity , TemperatureABSTRACT
The case history is described of a woman who presented with bilateral pleural effusions caused by Toxocara canis infestation. The condition responded rapidly to treatment.
Subject(s)
Pleural Effusion/parasitology , Toxocariasis/complications , Eosinophilia/parasitology , Female , Humans , Middle AgedABSTRACT
The incidence of airway colonization by Scedosporium apiospermum and of related sensitization was investigated prospectively in 128 patients with cystic fibrosis over a 5-year period, and results were compared with clinical data. Scedosporium apio-spermum, recovered from sputum samples in 11 of 128 (8.6%) patients, was the most frequent filamentous fungus after Aspergillus fumigatus. Counterimmuno-electrophoresis, used to detect scedosporiosis serologically, was positive in 27 of 128 (21.1%) patients. The discrepancy between the mycological and serological results may be related to immune cross-reactions between Scedosporium apiospermum and Aspergillus fumigatus. However, symptoms of allergic bronchopulmonary disease were observed in two patients chronically colonized by Scedosporium apiospermum. The results clearly demonstrate that the frequency of this fungus is largely underestimated and that it may trigger an inflammatory response, thus suggesting a pathogenic role in patients with cystic fibrosis.
Subject(s)
Antibodies, Fungal/blood , Cystic Fibrosis/microbiology , Pseudallescheria/pathogenicity , Sputum/microbiology , Adolescent , Adult , Aspergillosis, Allergic Bronchopulmonary/microbiology , Aspergillus fumigatus/immunology , Aspergillus fumigatus/isolation & purification , Bronchi/microbiology , Child , Cystic Fibrosis/immunology , Humans , Lung Diseases, Fungal/microbiology , Mycetoma/microbiology , Prospective Studies , Pseudallescheria/immunology , Pseudallescheria/isolation & purificationABSTRACT
Penicillium emersonii Stolk, the conidial state of Talaromyces emersoniii Stolk, is a heat-resistant fungus usually isolated from soil. In this paper the authors report, to our knowledge, the first human case in which P. emersonii chronically colonized the respiratory tract and induced an immune response in a patient with cystic fibrosis.
Subject(s)
Cystic Fibrosis/complications , Mycoses/microbiology , Penicillium/isolation & purification , Respiratory System/microbiology , Child , Humans , Male , Mycoses/complications , Sputum/microbiologyABSTRACT
In order to define the prevalence of Candida ciferrii in onychomycosis, the fungal biota associated with toe nail onyxis was examined in 50 elderly patients with trophic disorders of the legs and in 220 patients without clinical evidence of trophic disorders. Candida ciferrii was more frequent in the first group of patients since it was recovered from 24% of these patients, whereas its prevalence was only 1.4% in the control group. Moreover, the positivity of the direct examination of toe nail scrapings, the absence of any other associated pathogens, and the repeated isolation of this yeast species for some of the patients confirmed its pathogenicity.
Subject(s)
Candida/isolation & purification , Candidiasis/complications , Nails/microbiology , Onychomycosis/complications , Peripheral Vascular Diseases/complications , Adult , Aged , Aged, 80 and over , Antifungal Agents/pharmacology , Candida/drug effects , Candida/metabolism , Candidiasis/microbiology , Foot Dermatoses/complications , Foot Dermatoses/microbiology , Humans , Leg/blood supply , Microbial Sensitivity Tests , Middle Aged , Onychomycosis/microbiology , Oxidation-Reduction , Prospective Studies , Tetrazolium Salts/metabolism , ToesABSTRACT
The dematiaceous coelomycete Pleurophomopsis lignicola Petr. was isolated repeatedly in pure culture from a subcutaneous abscess of the left leg in a farmer undergoing corticosteroid therapy for asthma gravis. To our knowledge, we report the first case involving this fungus as an aetiological agent of subcutaneous phaeohyphomycosis.