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Olivier Lortholary

Publications and source records attributed to Olivier Lortholary.

At least 19 recordsLinked to original sources
PubMed2026

Invasive Wickerhamomyces anomalus Infections among Injecting Drug Users, France, 2012-20241.

Wickerhamomyces anomalus is a yeast rarely involved in human invasive fungal diseases (IFD). We retrospectively analyzed 44 episodes of W. anomalus IFD in France during 2012-2024. Injecting drug use (IDU) was the main risk factor among 26/35 (74.3%) incident cases. Most infections were community acquired; overall 3-month mortality rate was 1/30 (3.3%). Short tandem repeat (STR) genotyping and whole-genome sequencing analyses revealed substantial genetic diversity among isolates. However, 1 STR genotype was shared by 2 IDU patients, suggesting common exposure. In addition, 1 isolate obtained from a cotton filter used for drug preparation was identical by STR genotyping to the bloodstream isolate from the same patient, indicating direct inoculation via contaminated material or poor injection practices. Our findings highlight the increased risk for W. anomalus IFD among IDU patients and emphasize the importance of targeted preventive measures within that population.

Humans↗
PubMed2006

Imaging findings in acute invasive pulmonary aspergillosis: clinical significance of the halo sign.

BACKGROUND: Computed tomography (CT) of the chest may be used to identify the halo sign, a macronodule surrounded by a perimeter of ground-glass opacity, which is an early sign of invasive pulmonary aspergillosis (IPA). This study analyzed chest CT findings at presentation from a large series of patients with IPA, to assess the prevalence of these imaging findings and to evaluate the clinical utility of the halo sign for early identification of this potentially life-threatening infection. METHODS: Baseline chest CT imaging findings from 235 patients with IPA who participated in a previously published study were systematically analyzed. To evaluate the clinical utility of the halo sign for the early identification and treatment of IPA, we compared response to treatment and survival after 12 weeks of treatment in 143 patients who presented with a halo sign and in 79 patients with other imaging findings. RESULTS: At presentation, most patients (94%) had > or =1 macronodules, and many (61%) also had halo signs. Other imaging findings at presentation, including consolidations (30%), infarct-shaped nodules (27%), cavitary lesions (20%), and air-crescent signs (10%), were less common. Patients presenting with a halo sign had significantly better responses to treatment (52% vs. 29%; P<.001) and greater survival to 84 days (71% vs. 53%; P<.01) than did patients who presented with other imaging findings. CONCLUSIONS: Most patients presented with a halo sign and/or a macronodule in this large imaging study of IPA. Initiation of antifungal treatment on the basis of the identification of a halo sign by chest CT is associated with a significantly better response to treatment and improved survival.

Adolescent↗
PubMed2006

Long-term outcome of AIDS-associated cryptococcosis in the era of combination antiretroviral therapy.

BACKGROUND: Immune restoration following combination antiretroviral therapy (cART) questions the maintenance of prophylaxis among HIV-infected patients with cryptococcosis. OBJECTIVE: To describe the long-term outcome after the diagnosis of cryptococcosis at the cART era. DESIGN: Multicentre cohort of patients with a diagnosis of cryptococcosis between 1996 and 2000, follow-up until December 2002. Comparison with a historical cohort (1990-1994) for survival. SETTING: Eighty-four French AIDS clinical centres. PATIENTS: Two-hundred and forty HIV-infected adult patients at the cART era and 149 at the pre-cART era experiencing a first episode of culture-confirmed cryptococcosis. RESULTS: In the cART era, 82/189 patients surviving more than 3 months after initiation of antifungal therapy had their maintenance therapy interrupted with a subsequent median follow-up of 19 months. Their relapse rate per 100 person-years was 0.9 [95% confidence interval (CI),0.0-2.0]. When considering the whole cART cohort, probability of reaching negative serum cryptococcal antigen was 71% after 48 months of follow-up. A CD4 cell count < 100/microl [relative risk (RR), 5.5; 95% CI, 1.3-22.2], antifungal therapy < 3 months over the past 6 months [RR, 5.0; 95% CI, 1.1-22.3] and serum cryptococcal antigen titre > or = 1/512 [RR, 3.5; 95% CI, 1.1-10.8] were associated with a higher rate of cryptococcosis relapse. The mortality rate per 100 person-years was 15.3 [95% CI,12.2-18.4] in the cART era versus 63.8 [95% CI,53.0-74.9] in the pre-cART era although early mortality did not differ between the two periods. CONCLUSION: Overall survival after cryptococcosis has dramatically improved at the cART era. Immune restoration and low serum cryptococcal antigen titres are associated with lower cryptococcosis relapse rates.

AIDS-Related Opportunistic Infections↗
PubMed2006

Combination of amphotericin B with flucytosine is active in vitro against flucytosine-resistant isolates of Cryptococcus neoformans.

The combination of flucytosine and amphotericin B was tested against 10 flucytosine-resistant isolates of Cryptococcus neoformans by checkerboard, killing curves, and Etest. Although differences were observed depending on the technique used, antagonism was never observed. The synergistic interaction was related to the mechanism of flucytosine resistance of the isolates.

Amphotericin B↗
PubMed2006

Rapamycin inhibits growth and survival of D816V-mutated c-kit mast cells.

Two classes of oncogenic mutations of the c-kit tyrosine kinase have been described: the juxtamembrane domain V560G mutation, which is preferentially found in gastrointestinal stromal tumors (GISTs), and the kinase domain D816V mutation, which is highly representative of systemic mastocytosis (SM). Here we show that both mutations constitutively activate the mammalian target of rapamycin (mTOR) signaling pathway. Surprisingly, the mTOR inhibitor rapamycin induces only apoptosis in HMC-1 cells bearing the D816V but not the V560G mutation. In support of this unexpected selectivity, rapamycin inhibits the phosphorylation of 4E-BP1, a downstream substrate of the mTOR pathway, but only in D816V HMC-1 cells. Importantly, D816V mast cells isolated from SM patients or from transgenic mice are sensitive to rapamycin whereas normal human or mouse mast cells are not. Thus, rapamycin inhibition appears specific to the D816V mutation. At present there is no effective cure for SM patients with the D816V mutation. The data presented here provide a rationale to test whether rapamycin could be a possible treatment for SM and other hematologic malignancies with the D816V mutation.

Animals↗
PubMed2006

Morganella morganii pericarditis 3 years after allogenic bone marrow transplantation for mantle cell lymphoma.

We report herein a case of Morganella morganii-associated acute purulent pericarditis that developed 3 years after allogenic bone marrow transplantation. The patient was successfully treated with surgical drainage and cefotaxime for 6 weeks. Splenectomy and immunosuppression for chronic GVH-D are likely to have favored the development of this rare infectious complication after BMT. M. morganii should be added to the list of bacteria causing purulent pericarditis, especially in immunocompromised hosts.

Bone Marrow Transplantation↗
PubMed2006

Infection-associated lymphomas derived from marginal zone B cells: a model of antigen-driven lymphoproliferation.

Non-Hodgkin lymphomas develop from nodal and extranodal lymphoid tissues. A distinct subset of extranodal lymphomas arising from B cells of the marginal zone (MZ) of mucosa-associated lymphoid tissue (MALT) or spleen has been individualized. Growing evidence indicates that MZ lymphomas are associated with chronic antigenic stimulation by microbial pathogens and/or autoantigens. The list of microbial species associated with MZ lymphoproliferations has grown longer with molecular investigations and now comprises at least 5 distinct members: H. pylori, C. jejuni, B. burgdorferi, C. psittaci, and hepatitis C virus (HCV), which have been associated with gastric lymphoma, immunoproliferative small intestinal disease, cutaneous lymphoma, ocular lymphoma, and spleen lymphoma, respectively. A pathophysiologic scenario involving chronic and sustained stimulation of the immune system leading to lymphoid transformation has emerged. It defines a distinct category of infection-associated lymphoid malignancies, in which the infectious agent does not directly infect and transform lymphoid cells, as do the lymphotropic oncogenic viruses Epstein-Barr virus (EBV), human herpesvirus 8 (HHV8), and human T-lymphotropic virus 1 (HTLV-1), but rather indirectly increases the probability of lymphoid transformation by chronically stimulating the immune system to maintain a protracted proliferative state.

Antigen Presentation↗
PubMed2006

Immune reconstitution inflammatory syndrome in HIV-infected patients with disseminated histoplasmosis.

Four HIV-1-infected patients presented with unusual clinical manifestations in the course of disseminated histoplasmosis, including liver abscesses, compressive lymphadenitis, intestinal obstruction, uveitis and arthritis within a median of 45 days after initiation of highly active antiretroviral therapy (HAART). They had a median increase of 106 CD4 cells/mul and granulomas with caseation in three. Partial immune reconstitution induced by HAART during disseminated histoplasmosis either related to the variety capsulatum or duboisii may be associated with immune reconstitution inflammatory syndrome.

AIDS-Related Opportunistic Infections↗
PubMed2006

Efficacy of amphotericin B in combination with flucytosine against flucytosine-susceptible or flucytosine-resistant isolates of Cryptococcus neoformans during disseminated murine cryptococcosis.

Whether or not flucytosine should be administered to patients infected with Cryptococcus neoformans isolates found to be resistant to flucytosine in vitro remains a controversial issue. Thus, the efficacy of amphotericin B and flucytosine in combination was investigated by mortality and fungal burden studies in a murine model of disseminated cryptococcosis using two clinical isolates of Cryptococcus neoformans, one susceptible and one resistant (i.e., 64 microg/ml) to flucytosine. Amphotericin B was given intraperitoneally at 0.25 or 0.5 mg/kg/day, while flucytosine was given at 100 or 250 mg/kg/day orally. Treatment was started 24 h or day 6 after inoculation and continued for 5 days in fungal burden and mortality studies, respectively. The combination of amphotericin B at 0.5 mg/kg/day and flucytosine at 250 mg/kg/day was significantly more effective than monotherapies for reducing fungal burden in brain, spleen, and lungs after infection by the flucytosine-susceptible isolate and in brain and spleen for the flucytosine-resistant isolate. For the flucytosine-resistant isolate, the combination of amphotericin B at 0.5 mg/kg/day with flucytosine at 100 mg/kg/day was significantly better than monotherapies for reducing the fungal burden in the brain. Survival obtained after the combination of amphotericin B at 0.5 mg/kg/day and flucytosine at 250 mg/kg/day increased compared to that obtained with monotherapies for both isolates, but the difference was statistically significant only for the flucytosine-susceptible isolate. Antagonism was never observed. This study demonstrates the beneficial effect of the addition of flucytosine to amphotericin B against experimental disseminated cryptococcal infection even when the C. neoformans isolate is resistant to flucytosine.

Amphotericin B↗
PubMed2006

Molecular identification of black-grain mycetoma agents.

Black-grain mycetomas are subcutaneous devastating chronic infections due to several dematiaceous fungi. They are diagnosed mostly in tropical countries. Identification of these fungi with standard mycological procedures is difficult because of their poor or delayed sporulation. The aim of this study was thus to assess the accuracy of molecular identification of these fungi. A total of 54 strains, mostly of clinical origin, were used, including 15 Madurella mycetomatis, 6 Madurella grisea, 12 Leptosphaeria senegalensis, 4 Leptosphaeria tompkinsii, 6 Pyrenochaeta spp., 4 Curvularia lunata, and 7 Exophiala jeanselmei strains. The internal transcribed spacer 1 (ITS1)-5.8S-ITS2 DNA region was amplified by using universal fungal primers and sequenced. Both intra- and interspecies sequence similarities were assessed. Madurella mycetomatis appeared to be a homogeneous species. More intraspecies variations were found for C. lunata and E. jeanselmei, leading, in some instances, to changes in the initial identification. L. senegalensis and L. tompkinsii showed intraspecies similarities of >99%, but similarity between the two species was <88%. Intergenera and interspecies variations were important, with sequence homologies of <81% between genera. In contrast, Pyrenochaeta romeroi and M. grisea appeared to be heterogeneous, with intraspecies similarities of 40 to 100% and 53 to 100%, respectively, which suggest either erroneous identification or the need for taxonomic revision. Epidemiological and therapeutic studies could benefit from a precise identification of the fungi responsible for black-grain mycetoma based not only on phenotypical characteristics but also on ITS sequencing.

DNA, Fungal↗
PubMed2006

Molecular identification of zygomycetes from culture and experimentally infected tissues.

Mucormycosis is an emerging infection associated with a high mortality rate. Identification of the causative agents remains difficult and time-consuming by standard mycological procedures. In this study, internal transcribed spacer (ITS) sequencing was validated as a reliable technique for identification of Zygomycetes to the species level. Furthermore, species identification directly from infected tissues was evaluated in experimentally infected mice. Fifty-four Zygomycetes strains belonging to 16 species, including the most common pathogenic species of Rhizopus spp., Absidia spp., Mucor spp., and Rhizomucor spp., were used to assess intra- and interspecies variability. Ribosomal DNA including the complete ITS1-5.8S-ITS2 region was amplified with fungal universal primers, sequenced, and compared. Overall, for a given species, sequence similarities between isolates were >98%. In contrast, ITS sequences were very different between species, allowing an accurate identification of Zygomycetes to the species level in most cases. Six species (Rhizopus oryzae, Rhizopus microsporus, Rhizomucor pusillus, Mucor circinelloides, and Mucor indicus) were also used to induce disseminated mucormycosis in mice and to demonstrate that DNA extraction, amplification of fungal DNA, sequencing, and molecular identification were possible directly from frozen tissues.

Amino Acid Sequence↗
PubMed2006

Successful treatment of black-grain mycetoma with voriconazole.

Fungal mycetoma (or eumycetoma) are endemic diseases in tropical areas that have economic effects because of their chronic and disabling evolution. Classic treatments include surgery and antifungal drugs, but these have multiple side effects. We report a case of black-grain fungal mycetoma successfully treated with voriconazole without side effects. The duration of the treatment remains unclear, but must be prolonged because of the frequency of relapses.

Antifungal Agents↗
PubMed2005

Antifungal management practices and evolution of infection in organ transplant recipients with cryptococcus neoformans infection.

BACKGROUND: Therapeutic practices for Cryptococcus neoformans infection in transplant recipients vary, particularly with regards to antifungal agent employed, and duration of therapy. The risk of relapse and time to recurrence is not known. We assessed antifungal treatment practices for cryptococcosis in a cohort of prospectively followed organ transplant recipients. METHODS: The patients comprised 83 transplant recipients with cryptococcosis followed for a median of 2.1 and up to 5.2 years. RESULTS: Patients with central nervous system infection (69% vs. 16%, P = 0.00001), disseminated infection (82.7% vs. 20%, P = 0.00001), and fungemia (29% vs. 8%, P = 0.046) were more likely to receive regimens containing amphotericin B than fluconazole as primary therapy. The use of fluconazole, on the other hand, was more likely for infection limited to the lungs (64% vs. 14%, P = 0.00002). Survival at 6 months tended to be lower in patients whose CSF cultures at 2 weeks were positive compared to those whose CSF cultures were negative (50% vs. 91%, P = 0.06). Maintenance therapy was employed in 68% (54/79) of the patients who survived >3 weeks. The median duration of maintenance therapy was 183 days; 55% received maintenance for > or = 6 months and 25% for >1 year. Relapse was documented in 1.3% (1/79) of the patients. CONCLUSIONS: A majority of the organ transplant recipients with cryptococcosis receive maintenance antifungal therapy for 6 months with low risk of relapse. These data can assist in trials to assess the optimal therapeutic approach and duration of therapy for cryptococcosis in transplant recipients.

Adult↗
PubMed2005

Allograft loss in renal transplant recipients with cryptococcus neoformans associated immune reconstitution syndrome.

This study describes the association of allograft loss and immune reconstitution syndrome (IRS) in the course of Cryptococcosis neoformans infection in renal transplant recipients. Patients comprised 54 renal allograft recipients with cryptococcosis in a prospective, multicenter study. IRS developed in 5.5% (3/54) of the renal transplant recipient with C. neoformans infection. The renal allograft was lost to chronic rejection in 66% (2/3) of the patients with cryptococcosis who developed IRS compared to 5.9% (3/51) of those who did not (P=0.012). Kaplan-Meier survival analysis showed that subsequent to cryptococcal infection the probability of allograft survival was significantly lower in patients who developed IRS compared to those who did not develop IRS (P=0.0004). Temporal association of graft loss with IRS suggests a common pathophysiologic basis for these entities with implications relevant for the optimal management of renal transplant recipients with cryptococcosis.

Cryptococcosis↗
PubMed2005

[Systemic mastocytosis].

Systemic mastocytosis is characterized by mast cell proliferation in different organs. Classification delineates 4 categories: indolent systemic mastocytosis, systemic mastocytosis with an associated clonal hematologic non-mast cell lineage disease, aggressive systemic mastocytosis and mast cell leukaemia. Clinical manifestations are due to organ infiltration (skin, bone, gut, liver, spleen, lymph nodes) and release of mast-cell mediators. Diagnosis of mastocytosis is based on appropriate stains (Giemsa, Toluidine) and immunophenotype features (tryptase, CD117). Serum level of tryptase reflects the total burden of mast cells. Treatment must prevent mast cell mediators release (histamine antagonists, cromolyn sodium, corticosteroids, leukotriene-receptor inhibitors) and have a cytoreductive effect (interferon, cladribine, tyrosine kinase inhibitors).

Enzyme Inhibitors↗