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Dive into the research topics where Maria N. Gamaletsou is active.

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Featured researches published by Maria N. Gamaletsou.


Current Infectious Disease Reports | 2012

Rhino-orbital-cerebral mucormycosis.

Maria N. Gamaletsou; Nikolaos V. Sipsas; Emmanuel Roilides; Thomas J. Walsh

This review focuses on sinus, sino-orbital, and rhinocerebral infection caused by the Mucorales. As the traditional term of “rhinocerebral” mucormycosis omits the critical involvement of the eye, the more comprehensive term as rhino-orbital-cerebral mucormycosis (ROCM) is used. The most common underlying illnesses of ROCM are diabetes mellitus, hematological malignancies, hematopoietic stem cell transplantation, and solid organ transplantation. Sporangiospores are deposited in the nasal turbinates and paranasal sinuses in immunocompromised patients. Qualitative and quantitative abnormalities of neutrophils, monocytes and macrophages increase the risk for development of mucormycosis. Altered iron metabolism also is a critical factor in the pathogenesis of patients with diabetes mellitus who are at risk for ROCM. Angioinvasion with thrombosis and tissue necrosis is a key pathophysiological feature of human Mucorales infection. The ethmoid sinus is a critical site from which sinus mucormycosis may extend through the lamina papyracea into the orbit, extraocular muscles, and optic nerve. The brain may be seeded by invasion of the ethmoidal and orbital veins, which drain into the cavernous sinuses. Diplopia and ophthalmoplegia may be the earliest manifestations of cavernous sinus syndrome before changes are apparent on diagnostic imaging modalities. Negative diagnostic imaging does not exclude cavernous sinus mucormycosis. Mucormycosis of the maxillary sinus has a constellation of clinical features that are different from that of ethmoid sinus mucormycosis. A painful black necrotic ulceration may develop on the hard palate, indicating extension from the maxillary sinus into the oral cavity. Orbital apex syndrome is an ominous complication of mucormycosis of the orbit. Once within the orbital compartment, organisms may extend posteriorly to the optic foramen, where the ophthalmic artery, ophthalmic nerve and optic nerve are threatened by invasion, edema, inflammation and necrosis. Early diagnosis of sinus mucormycosis is critical for prevention of extension to orbital and cerebral tissues. Optimal therapy requires a multidisciplinary approach that relies on prompt institution of appropriate antifungal therapy with amphotericin B, reversal of underlying predisposing conditions, and, where possible, surgical debridement of devitalized tissue. Outcomes are highly dependent upon the degree of immunosuppression, site and extent of infection, timeliness of therapy, and type of treatment provided. New modalities for early diagnosis and therapeutic intervention are critically needed for improved outcome of patients with ROCM.


Clinical Infectious Diseases | 2012

Candida Osteomyelitis: Analysis of 207 Pediatric and Adult Cases (1970–2011)

Maria N. Gamaletsou; Dimitrios P. Kontoyiannis; Nikolaos V. Sipsas; Brad Moriyama; Elizabeth L. Alexander; Emmanuel Roilides; Barry Brause; Thomas J. Walsh

BACKGROUND The epidemiology, pathogenesis, clinical manifestations, management, and outcome of Candida osteomyelitis are not well understood. METHODS Cases of Candida osteomyelitis from 1970 through 2011 were reviewed. Underlying conditions, microbiology, mechanisms of infection, clinical manifestations, antifungal therapy, and outcome were studied in 207 evaluable cases. RESULTS Median age was 30 years (range, ≤ 1 month to 88 years) with a >2:1 male:female ratio. Most patients (90%) were not neutropenic. Localizing pain, tenderness, and/or edema were present in 90% of patients. Mechanisms of bone infection followed a pattern of hematogenous dissemination (67%), direct inoculation (25%), and contiguous infection (9%). Coinciding with hematogenous infection, most patients had ≥2 infected bones. When analyzed by age, the most common distribution of infected sites for adults was vertebra (odds ratio [OR], 0.09; 95% confidence interval [CI], .04-.25), rib, and sternum; for pediatric patients (≤18 years) the pattern was femur (OR, 20.6; 95% CI, 8.4-48.1), humerus, then vertebra/ribs. Non-albicans Candida species caused 35% of cases. Bacteria were recovered concomitantly from 12% of cases, underscoring the need for biopsy and/or culture. Candida septic arthritis occurred concomitantly in 21%. Combined surgery and antifungal therapy were used in 48% of cases. The overall complete response rate of Candida osteomyelitis of 32% reflects the difficulty in treating this infection. Relapsed infection, possibly related to inadequate duration of therapy, occurred among 32% who ultimately achieved complete response. CONCLUSIONS Candida osteomyelitis is being reported with increasing frequency. Localizing symptoms are usually present. Vertebrae are the most common sites in adults vs femora in children. Timely diagnosis of Candida osteomyelitis with extended courses of 6-12 months of antifungal therapy, and surgical intervention, when indicated, may improve outcome.


Clinical Microbiology and Infection | 2014

A prospective, cohort, multicentre study of candidaemia in hospitalized adult patients with haematological malignancies

Maria N. Gamaletsou; Thomas J. Walsh; Theoklis E. Zaoutis; M. Pagoni; M. Kotsopoulou; M. Voulgarelis; P. Panayiotidis; T. Vassilakopoulos; Maria K. Angelopoulou; Markos Marangos; Alexandros Spyridonidis; D. Kofteridis; A. Pouli; D. Sotiropoulos; P. Matsouka; A. Argyropoulou; S. Perloretzou; Kateri H. Leckerman; A. Manaka; P. Oikonomopoulos; George L. Daikos; George Petrikkos; Nikolaos V. Sipsas

Invasive candidiasis is a life-threatening infection in patients with haematological malignancies. The objective of our study was to determine the incidence, microbiological characteristics and clinical outcome of candidaemia among hospitalized adult patients with haematological malignancies. This is a population-based, prospective, multicentre study of patients ≥ 18 years admitted to haematology and/or haematopoietic stem cell transplantation units of nine tertiary care Greek hospitals from January 2009 through to February 2012. Within this cohort, we conducted a nested case-control study to determine the risk factors for candidaemia. Stepwise logistic regression was used to identify independent predictors of 28-day mortality. Candidaemia was detected in 40 of 27,864 patients with haematological malignancies vs. 967 of 1,158,018 non-haematology patients for an incidence of 1.4 cases/1000 admissions vs. 0.83/1000 respectively (p <0.001). Candidaemia was caused predominantly (35/40, 87.5%) by non-Candida albicans species, particularly Candida parapsilosis (20/40, 50%). In vitro resistance to at least one antifungal agent was observed in 27% of Candida isolates. Twenty-one patients (53%) developed breakthrough candidaemia while receiving antifungal agents. Central venous catheters, hypogammaglobulinaemia and a high APACHE II score were independent risk factors for the development of candidaemia. Crude mortality at day 28 was greater in those with candidaemia than in control cases (18/40 (45%) vs. 9/80 (11%); p <0.0001). In conclusion, despite antifungal prophylaxis, candidaemia is a relatively frequent infection associated with high mortality caused by non-C. albicans spp., especially C. parapsilosis. Central venous catheters and hypogammaglobulinaemia are independent risk factors for candidaemia that provide potential targets for improving the outcome.


Hematology | 2013

Treatment of fungal disease in the setting of neutropenia

Thomas J. Walsh; Maria N. Gamaletsou

Invasive fungal infections are important causes of morbidity and attributable mortality in neutropenic patients with hematological malignancies, myelodysplasia, and aplastic anemia. Successful risk-based strategies can be implemented for prophylaxis, empirical therapy, and preemptive therapy for the prevention and early treatment of invasive fungal infections in neutropenic hosts. The use of echinocandins for invasive candidiasis and voriconazole for invasive aspergillosis has significantly improved outcome. Recent studies demonstrate, however, that resistant fungal pathogens may emerge during the course of these antifungal interventions. Although triazole-resistant Candida spp. have been well described as causes of breakthrough candidemia, other organisms now pose a similar threat. Such organisms include echinocandin-resistant Candida glabrata and Candida parapsilosis species complex. The Mucorales, Fusarium spp., and Scedosporium spp. may emerge in the setting of voriconazole prophylaxis. The challenges of these emerging pathogens underscore the need for the development of new antifungal agents and strategies.


Journal of Infection | 2014

Aspergillus osteomyelitis: Epidemiology, clinical manifestations, management, and outcome

Maria N. Gamaletsou; Blandine Rammaert; Marimelle A. Bueno; Brad Moriyama; Nikolaos V. Sipsas; Dimitrios P. Kontoyiannis; Emmanuel Roilides; Valérie Zeller; Roberta Prinapori; Saad J. Taj-Aldeen; Barry Brause; Olivier Lortholary; Thomas J. Walsh

BACKGROUND The epidemiology, pathogenesis, diagnosis, and management of Aspergillus osteomyelitis are not well understood. METHODS Protocol-defined cases of Aspergillus osteomyelitis published in the English literature were reviewed for comorbidities, microbiology, mechanisms of infection, clinical manifestations, radiological findings, inflammatory biomarkers, antifungal therapy, and outcome. RESULTS Among 180 evaluable patients, 127 (71%) were males. Possible predisposing medical conditions in 103 (57%) included pharmacological immunosuppression, primary immunodeficiency, and neutropenia. Seventy-three others (41%) had prior open fracture, trauma or surgery. Eighty (44%) followed a hematogenous mechanism, 58 (32%) contiguous infections, and 42 (23%) direct inoculation. Aspergillus osteomyelitis was the first manifestation of aspergillosis in 77%. Pain and tenderness were present in 80%. The most frequently infected sites were vertebrae (46%), cranium (23%), ribs (16%), and long bones (13%). Patients with vertebral Aspergillus osteomyelitis had more previous orthopedic surgery (19% vs 0%; P = 0.02), while those with cranial osteomyelitis had more diabetes mellitus (32% vs 8%; P = 0.002) and prior head/neck surgery (12% vs 0%; P = 0.02). Radiologic findings included osteolysis, soft-tissue extension, and uptake on T2-weighted images. Vertebral body Aspergillus osteomyelitis was complicated by spinal-cord compression in 47% and neurological deficits in 41%. Forty-four patients (24%) received only antifungal therapy, while 121 (67%) were managed with surgery and antifungal therapy. Overall mortality was 25%. Median duration of therapy was 90 days (range, 10-772 days). There were fewer relapses in patients managed with surgery plus antifungal therapy in comparison to those managed with antifungal therapy alone (8% vs 30%; P = 0.006). CONCLUSIONS Aspergillus osteomyelitis is a debilitating infection affecting both immunocompromised and immunocompetent patients. The most common sites are vertebrae, ribs, and cranium. Based upon this comprehensive review, management of Aspergillus osteomyelitis optimally includes antifungal therapy and selective surgery to avoid relapse and to achieve a complete response.


Arthritis Research & Therapy | 2011

Is Sjögren's syndrome a retroviral disease?

Nikolaos V. Sipsas; Maria N. Gamaletsou; Haralampos M. Moutsopoulos

Circumstantial evidence suggests that retroviruses play a role in the pathogenesis of Sjögrens syndrome. Such evidence, derived from studies of patients with Sjögrens syndrome, includes the following: the presence of serum antibodies cross-reactive with retroviral Gag proteins; the occurrence of reverse transcriptase activity in salivary glands; the detection of retroviral antigens, retrovirus-like particles, or novel retroviral sequences in salivary glands; the occurrence of Sjögrens syndrome-like illnesses in patients having confirmed systematic infections with retroviruses such as human immunodeficiency virus-1 (HIV-1) and human T lymphotropic virus type 1; and the beneficial effect of anti-retroviral treatment on the occurrence of HIV-1-associated sicca syndrome. Additional evidence is provided by animal models.


Medical Mycology | 2013

Increased virulence of Cunninghamella bertholletiae in experimental pulmonary mucormycosis: correlation with circulating molecular biomarkers, sporangiospore germination and hyphal metabolism

Vidmantas Petraitis; Ruta Petraitiene; Charalampos Antachopoulos; Johanna E. Hughes; Margaret P. Cotton; Miki Kasai; Susan M. Harrington; Maria N. Gamaletsou; John Bacher; Dimitrios P. Kontoyiannis; Emmanuel Roilides; Thomas J. Walsh

Members of the order Mucorales are emerging invasive molds that cause infections in immunocompromised patients. However, little is known about the relation between different species of Mucorales and their virulence in invasive pulmonary mucormycosis. Based upon our earlier epidemiological studies, we hypothesized that Cunninghamella bertholletiae would demonstrate increased virulence. Therefore, we studied the relative virulence of C. bertholletiae (CB), Rhizopus oryzae (RO), R. microsporus (RM), and Mucor circinelloides (MC) in experimental invasive pulmonary mucormycosis in persistently neutropenic rabbits in relation to the fungi in vitro sporangiospore germination rate and hyphal metabolic activity. Rabbits infected with CB demonstrated (1) higher lung weights in comparison to RM (P ≤ 0.05), RO and MC (P ≤ 0.001), (2) pulmonary infarcts in comparison to RO and MC (P ≤ 0.001), (3) tissue fungal burden (CFU/g) vs. MC (P ≤ 0.001), and (4) the lowest survival of 0% (0/18), in comparison to 16% (3/18, P ≤ 0.01) of RM, 81% (21/26) of RO, and 83% (15/18) of MC-infected rabbits (P ≤ 0.001). Serum PCR concentration-time-curve showed the greatest amplitude for CB. Virulence correlated directly with sporangiospore germination rate at 4 h among species, i.e., CB (67-85%) > RM (14-56%) > RO (4-30%) > MC (0%), and hyphal metabolic activity, i.e., CB (1.22-1.51) > MC (0.54-0.64) = RM (0.38-0.41) = RO (0.37-0.59). C. bertholletiae was significantly more virulent in experimental invasive pulmonary mucormycosis than R. microsporus, R. oryzae, and M. circinelloides. In vivo virulence correlated with species-dependent differences of in vitro germination rate and hyphal metabolic activity.


Diagnostic Microbiology and Infectious Disease | 2012

Successful salvage therapy of refractory HIV-related cryptococcal meningitis with the combination of liposomal amphotericin B, voriconazole, and recombinant interferon-γ

Maria N. Gamaletsou; Nikolaos V. Sipsas; Dimitrios P. Kontoyiannis; Aristotelis Tsiakalos; Athanasios Kontos; Ioanna Stefanou; Theodore Kordossis

We present 2 cases of HIV-related cryptococcal meningitis, persisting after 3 and 9 months, respectively, of standard treatment. Both patients were treated successfully with a salvage regimen consisting of the combination of liposomal amphotericin B (3 mg/kg), intravenous voriconazole, and subcutaneous recombinant interferon γ-1b (200 μg thrice weekly). Voriconazole was administered at an increased dose (5 mg/kg, twice daily) to overcome interactions with co-administered ritonavir. In both patients, resolution of clinical signs and symptoms, as well as sterilization of cerebrospinal fluid cultures occurred after 10 weeks of salvage therapy. No major side effects were encountered. At the end of treatment, both patients were placed on maintenance therapy with oral fluconazole; no recurrence has been observed after 4 years of follow-up.


Medicine | 2015

Osteoarticular infections caused by non-Aspergillus filamentous fungi in adult and pediatric patients: A systematic review

Saad J. Taj-Aldeen; Blandine Rammaert; Maria N. Gamaletsou; Nikolaos V. Sipsas; Valérie Zeller; Emmanuel Roilides; Dimitrios P. Kontoyiannis; Andy O. Miller; Vidmantas Petraitis; Thomas J. Walsh; Olivier Lortholary

AbstractOsteoarticular mycoses due to non-Aspergillus moulds are uncommon and challenging infections.A systematic literature review of non-Aspergillus osteoarticular mycoses was performed using PUBMED and EMBASE databases from 1970 to 2013.Among 145 patients were 111 adults (median age 48.5 [16–92 y]) and 34 pediatric patients (median age 7.5 [3–15 y]); 114 (79.7%) were male and 88 (61.9%) were immunocompromised. Osteomyelitis was due to direct inoculation in 54.5%. Trauma and puncture wounds were more frequent in children (73.5% vs 43.5%; P = 0.001). Prior surgery was more frequent in adults (27.7% vs 5.9%; P = 0.025). Vertebral (23.2%) and craniofacial osteomyelitis (13.1%) with neurological deficits predominated in adults. Lower limb osteomyelitis (47.7%) and knee arthritis (67.8%) were predominantly seen in children. Hyalohyphomycosis represented 64.8% of documented infections with Scedosporium apiospermum (33.1%) and Lomentospora prolificans (15.8%) as the most common causes. Combined antifungal therapy and surgery was used in 69% of cases with overall response in 85.8%. Median duration of therapy was 115 days (range 5–730). When voriconazole was used as single agent for treatment of hyalohyphomycosis and phaeohyphomycosis, an overall response rate was achieved in 94.1% of cases.Non-Aspergillus osteoarticular mycoses occur most frequently in children after injury and in adults after surgery. Accurate early diagnosis and long-course therapy (median 6 mo) with a combined medical-surgical approach may result in favorable outcome.


Journal of Hospital Infection | 2012

Nutritional risk as predictor for healthcare-associated infection among hospitalized elderly patients in the acute care setting.

Maria N. Gamaletsou; Kalliopi-Anna Poulia; Dimitra Karageorgou; Mary Yannakoulia; P.D. Ziakas; Antonis Zampelas; Nikolaos V. Sipsas

BACKGROUND Poor nutritional status is associated with high rates of healthcare-associated infections (HCAIs) among hospitalized elderly patients. Early recognition of patients at risk for HCAIs is important. The Geriatric Nutritional Risk Index (GNRI) is a screening tool able to predict nutrition-related complications. AIM To examine the use of GNRI as a predictor of HCAIs in the acute care setting. METHODS A total of 248 consecutive patients aged >65 years, admitted as emergencies to the medical ward of an acute care hospital, were enrolled. On admission, clinical and laboratory assessment, anthropometric measurements, performance status, and GNRI score estimation were performed. HCAIs were recorded during admission. FINDINGS On admission, 53.8% of the patients were not at risk, 37.2% at low or medium risk and 8.9% at high risk for nutrition-related complications, as stratified by using the GNRI. During hospitalization 23.7% of the patients developed HCAIs. Patients with HCAIs had higher mortality (P < 0.001) and longer hospital stay (P < 0.001). In multivariate analysis, a performance status >1 [hazard ratio (HR): 2.08; 95% confidence interval (CI): 1.07-4.02; P = 0.03] and diabetes (HR: 2.57; 95% CI: 1.37-4.84; P = 0.003) were associated with increased risk for HCAIs, whereas GNRI score (per unit increase) had a protective effect (HR: 0.97; 95% CI: 0.95-0.99; P = 0.01). Well-nourished patients (GNRI >98) were significantly more likely to remain free from HCAIs during hospitalization (P = 0.003). CONCLUSION GNRI can accurately stratify hospitalized elderly patients according to risk for developing HCAIs.

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Nikolaos V. Sipsas

National and Kapodistrian University of Athens

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Dimitrios P. Kontoyiannis

University of Texas MD Anderson Cancer Center

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Brad Moriyama

National Institutes of Health

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David W. Denning

Manchester Academic Health Science Centre

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