Effectiveness of fosfomycin trometamol as oral step-down therapy for bacteraemic urinary tract infections due to MDR Escherichia coli: a post hoc analysis of the FOREST randomized trial.

BACKGROUND: Fosfomycin is a potentially attractive option as step-down therapy for bacteraemic urinary tract infections (BUTI), but available data are scarce. Our objective was to compare the effectiveness and safety of fosfomycin trometamol and other oral drugs as step-down therapy in patients with BUTI due to MDR Escherichia coli (MDR-Ec). METHODS: Participants in the FOREST trial (comparing IV fosfomycin with ceftriaxone or meropenem for BUTI caused by MDR-Ec in 22 Spanish hospitals from June 2014 to December 2018) who were stepped-down to oral fosfomycin (3 g q48h) or other drugs were included. The primary endpoint was clinical and microbiological cure (CMC) 5-7 days after finalization of treatment. A multivariate analysis was performed using logistic regression to estimate the association of oral step-down with fosfomycin with CMC adjusted for confounders. RESULTS: Overall, 61 patients switched to oral fosfomycin trometamol and 47 to other drugs (cefuroxime axetil, 28; amoxicillin/clavulanic acid and trimethoprim/sulfamethoxazole, 7 each; ciprofloxacin, 5) were included. CMC was reached by 48/61 patients (78.7%) treated with fosfomycin trometamol and 38/47 (80.9%) with other drugs (difference, -2.2; 95% CI: -17.5 to 13.1; P = 0.38). Subgroup analyses provided similar results. Relapses occurred in 9/61 (15.0%) and 2/47 (4.3%) of patients, respectively (P = 0.03). The adjusted OR for CMC was 1.11 (95% CI: 0.42-3.29, P = 0.75). No relevant differences in adverse events were seen. CONCLUSIONS: Fosfomycin trometamol might be a reasonable option as step-down therapy in patients with BUTI due to MDR-Ec but the higher rate of relapses would need further assessment.

DALBACEN cohort: dalbavancin as consolidation therapy in patients with endocarditis and/or bloodstream infection produced by gram-positive cocci.

OBJECTIVES: To analyse the effectiveness of dalbavancin (DBV) in clinical practice as consolidation therapy in patients with bloodstream infection (BSI) and/or infective endocarditis (IE) produced by gram-positive cocci (GPC), as well as its safety and pharmacoeconomic impact. METHODS: A multicentre, observational and retrospective study was conducted of hospitalised patients with IE and/or BSI produced by GPC who received at least one dose of DBV. Clinical response was assessed during hospitalization, at 3 months and at 1 year. RESULTS: Eighty-three patients with median age of 73 years were enrolled; 73.5% were male; 59.04% had BSI and 49.04% IE (44.04% prosthetic valve IE, 32.4% native IE, 23.5% pacemaker lead). The most frequently isolated microorganism was Staphylococcus aureus in BSI (49%) and coagulase-negative staphylococci in IE (44.1%). All patients with IE were clinically cured in hospital; at 12 months, there was 2.9% loss to follow-up, 8.8% mortality unrelated to IE, and 2.9% therapeutic failure rate. The percentage effectiveness of DBV to treat IE was 96.7%. The clinical cure rate for BSI was 100% during hospital stay and at 3 months; there were no recurrences or deaths during the follow-up. No patient discontinued treatment for adverse events. The saving in hospital stay was 636 days for BSI (315,424.20€) and 557 days for IE (283,187.45€). CONCLUSIONS: DBV is an effective consolidation antibiotic therapy in clinically stabilized patients with IE and/or BSI. It proved to be a cost-effective treatment, reducing the hospital stay, thanks to the pharmacokinetic/pharmacodynamic profile of this drug.

High delayed mortality after the first episode of Clostridium difficile infection.

Clostridium difficile infection (CDI) is characterized by a high delayed and unrelated mortality. Predicting delayed mortality in CDI patients could allow the implementation of interventions that could reduce these events. A prospective multicentric study was carried out to investigate prognostic factors associated with mortality. It was based on a cohort (July 2015 to February 2016) of 295 patients presenting with CDI. Logistic regression was used and the model was calibrated using the Hosmer-Lemeshow test. The mortality rate at 75 days in our series was 18%. Age (>65 years), comorbidity (defined by heart failure, diabetes mellitus with any organ lesion, renal failure, active neoplasia or immunosuppression) and fecal incontinence at clinical presentation were associated with delayed (75-day) mortality. When present, each of the aforementioned variables added one point to the score. Mortalities with 0, 1, 2 and 3 points were 0%, 9.4%, 18.5% and 38.2%, respectively. The area under the ROC curve was 0.743, and the Hosmer-Lemeshow goodness-of-fit test p value was 0.875. Therefore, the prediction of high delayed mortality in CDI patients by our scoring system could promote measures for increasing survival in suitable cases.

Methicillin-resistant Staphylococcus aureus (MRSA) catheter-related bacteraemia in haemodialysis patients.

BACKGROUND: The aim of the study was to determine clinical and microbiological differences between patients with methicillin-resistant Staphylococcus aureus (MRSA) catheter-related bacteraemia (CRB) undergoing or not undergoing haemodialysis, and to compare outcomes. METHODS: Prospective multicentre study conducted at 21 Spanish hospitals of patients with MRSA bacteraemia diagnosed between June 2008 and December 2009. Patients with MRSA-CRB were selected. Data of patients on haemodialysis (HD-CRB) and those not on haemodialysis (non-HD-CRB) were compared. RESULTS: Among 579 episodes of MRSA bacteraemia, 218 (37.7%) were CRB. Thirty-four (15.6%) were HD-CRB and 184 (84.4%) non-HD-CRB. All HD-CRB patients acquired the infection at dialysis centres, while in 85.3% of the non-HD-CRB group the infection was nosocomial (p < .001). There were no differences in age, gender or severity of bacteraemia (Pitt score); comorbidities (Charlson score ≥ 4) were higher in the HD-CRB group than in the non-HD-CRB group (73.5% vs. 46.2%, p = .003). Although there were no differences in VAN-MIC ≥ 1.5 mg/L according to microdilution, using the E-test a higher rate of VAN-MIC ≥ 1.5 mg/L was observed in HD-CRB than in non-HD-CRB patients (63.3% vs. 44.1%, p = .051). Vancomycin was more frequently administered in the HD-CRB group than in the non-HD-CRB group (82.3% vs. 42.4%, p = <.001) and therefore the appropriate empirical therapy was significantly higher in HD-CRB group (91.2% vs. 73.9%, p = .029). There were no differences with regard to catheter removal (79.4% vs. 84.2%, p = .555, respectively). No significant differences in mortality rate were observed between both groups (Overall mortality: 11.8% vs. 27.2%, p = .081, respectively), but there was a trend towards a higher recurrence rate in HD-CRB group (8.8% vs. 2.2%, p = .076). CONCLUSIONS: In our multicentre study, ambulatory patients in chronic haemodialysis represented a significant proportion of cases of MRSA catheter-related bacteraemia. Although haemodialysis patients with MRSA catheter-related bacteraemia had significantly more comorbidities and higher proportion of strains with reduced vancomycin susceptibility than non-haemodialysis patients, overall mortality between both groups was similar.

Predominance of CXCR4 tropism in HIV-1 CRF14_BG strains from newly diagnosed infections.

OBJECTIVES: R5-tropic viruses are associated with HIV-1 transmission and predominate during the early stages of infection. X4-tropic populations have been detected in ~50% of patients with late-stage disease infected with subtype B viruses. In this study, we compared the frequency of X4 tropism in individuals infected with HIV-1 CRF14_BG viruses, which have a V3 loop of subtype B, with a control group of individuals infected with subtype B viruses. METHODS: Sixty-three individuals infected with HIV-1 CRF14_BG (n = 31) or subtype B (n = 32) were studied. Similar proportions of newly diagnosed and chronically infected individuals were included in the subtype B and CRF14_BG groups. V3 sequences were obtained and coreceptor tropism was predicted using the Geno2pheno[coreceptor] algorithm. V3 net charge and 11/25 rules were also used for coreceptor prediction. RESULTS: Overall, X4 tropism was more frequent among individuals infected with CRF14_BG viruses (87.1%) than subtype B viruses (34.3%), a difference that was statistically highly significant (P = 0.00001). Importantly, the frequencies among newly diagnosed individuals were 90% and 13.3%, respectively (P = 0.0007). Characteristic amino acids in the V3 loop (T13, M14, V19 and W20) were identified at higher frequencies in CRF14_BG viruses (54%) than subtype B viruses (0%; P < 0.000001). CONCLUSIONS: CRF14_BG is the genetic form with the highest proportion of X4-tropic viruses reported to date in newly diagnosed and chronic infections. This suggests high pathogenicity for CRF14_BG viruses, potentially leading to rapid disease progression. CCR5 antagonists will be ineffective in most CRF14_BG-infected patients, even at early stages of infection.

Abdominal aortic endograft infection. A decade of experience and literature review.

INTRODUCTION: Aortic endograft infection is an infrequent but life-threatening complication after endovascular abdominal aortic repair (EVAR). There is no consensus on management of endograft infection and little evidence has been published in our country. Endograft explantation is considered the "gold standar" treatment whereas percutaneous or surgical perigraft and sac drainage associated to antibiotics should be considered and alternative therapy. METHODS: We carried out a retrospective and descriptive review of abdominal aortic endograft infections at our tertiary center (Hospital Universitario Cruces) during last ten years (2010-2019). RESULTS: We describe the clinical and microbiological characteristics of 10 EVAR infections, their management and outcomes. The incidence of graft infection after EVAR was 3%. The mean time to the clinical presentation of infection was 16.9 months (median 4.5 months). The microbiological diagnosis was reached in 100% of cases (predominance of gram-positive species). The overall mortality rate was 50% (although the survival rate was 100% after surgical drainage of the sac). CONCLUSION: Perigraft or aneurysm sac aspiration culture show their diagnostic utility as microbiological diagnosis was reached in all cases despite of blood cultures being only positive in 50% of the samples. Surgical drainage and endograft preservation combined with antibiotherapy show remarkable results. The high heterogeneity in our case series makes difficult to offer general recommendations, thus far, a tailored approach to treatment is suggested.

Randomized Clinical Trial of the Need for Antibiotic Treatment for Low-Risk Catheter-Related Bloodstream Infection Caused by Coagulase-Negative Staphylococci.

According to clinical guidelines, the management of catheter-related bloodstream infections (CRBSI) due to coagulase-negative staphylococci (CoNS) includes catheter removal and antibiotic treatment for 5 to 7 days. However, in low-risk episodes, it remains uncertain whether antibiotic therapy is necessary. This randomized clinical trial aims to determine whether the non-administration of antibiotic therapy is as safe and effective as the recommended strategy in low-risk episodes of CRBSI caused by CoNS. With this purpose, a randomized, open-label, multicenter, non-inferiority clinical trial was conducted in 14 Spanish hospitals from 1 July 2019 to 31 January 2022. Patients with low-risk CRBSI caused by CoNS were randomized 1:1 after catheter withdrawal to receive/not receive parenteral antibiotics with activity against the isolated strain. The primary endpoint was the presence of any complication related to bacteremia or to antibiotic therapy within 90 days of follow-up. The secondary endpoints were persistent bacteremia, septic embolism, time until microbiological cure, and time until the disappearance of a fever. EudraCT: 2017-003612-39 INF-BACT-2017. A total of 741 patients were assessed for eligibility. Of these, 27 were included in the study; 15 (55.6%) were randomized to the intervention arm (non-antibiotic administration) and 12 (44.4%) to the control arm (antibiotic therapy as per standard practice). The primary endpoint occurred in one of the 15 patients in the intervention group (septic thrombophlebitis) and in no patients in the control group. The median time until microbiological cure was 3 days (IQR 1-3) in the intervention arm and 1.25 days (IQR 0.5-2.62) in the control arm, while the median time until fever resolution was zero days in both arms. The study was stopped due to the insufficient number of recruited patients. These results seem to indicate that low-risk CRBSI caused by CoNS can be managed without antibiotic therapy after catheter removal; efficacy and safety are not affected.

Effectiveness of Fosfomycin for the Treatment of Multidrug-Resistant Escherichia coli Bacteremic Urinary Tract Infections: A Randomized Clinical Trial.

Importance: The consumption of broad-spectrum drugs has increased as a consequence of the spread of multidrug-resistant (MDR) Escherichia coli. Finding alternatives for these infections is critical, for which some neglected drugs may be an option. Objective: To determine whether fosfomycin is noninferior to ceftriaxone or meropenem in the targeted treatment of bacteremic urinary tract infections (bUTIs) due to MDR E coli. Design, Setting, and Participants: This multicenter, randomized, pragmatic, open clinical trial was conducted at 22 Spanish hospitals from June 2014 to December 2018. Eligible participants were adult patients with bacteremic urinary tract infections due to MDR E coli; 161 of 1578 screened patients were randomized and followed up for 60 days. Data were analyzed in May 2021. Interventions: Patients were randomized 1 to 1 to receive intravenous fosfomycin disodium at 4 g every 6 hours (70 participants) or a comparator (ceftriaxone or meropenem if resistant; 73 participants) with the option to switch to oral fosfomycin trometamol for the fosfomycin group or an active oral drug or parenteral ertapenem for the comparator group after 4 days. Main Outcomes and Measures: The primary outcome was clinical and microbiological cure (CMC) 5 to 7 days after finalization of treatment; a noninferiority margin of 7% was considered. Results: Among 143 patients in the modified intention-to-treat population (median [IQR] age, 72 [62-81] years; 73 [51.0%] women), 48 of 70 patients (68.6%) treated with fosfomycin and 57 of 73 patients (78.1%) treated with comparators reached CMC (risk difference, -9.4 percentage points; 1-sided 95% CI, -21.5 to ∞ percentage points; P = .10). While clinical or microbiological failure occurred among 10 patients (14.3%) treated with fosfomycin and 14 patients (19.7%) treated with comparators (risk difference, -5.4 percentage points; 1-sided 95% CI, -∞ to 4.9; percentage points; P = .19), an increased rate of adverse event-related discontinuations occurred with fosfomycin vs comparators (6 discontinuations [8.5%] vs 0 discontinuations; P = .006). In an exploratory analysis among a subset of 38 patients who underwent rectal colonization studies, patients treated with fosfomycin acquired a new ceftriaxone-resistant or meropenem-resistant gram-negative bacteria at a decreased rate compared with patients treated with comparators (0 of 21 patients vs 4 of 17 patients [23.5%]; 1-sided P = .01). Conclusions and Relevance: This study found that fosfomycin did not demonstrate noninferiority to comparators as targeted treatment of bUTI from MDR E coli; this was due to an increased rate of adverse event-related discontinuations. This finding suggests that fosfomycin may be considered for selected patients with these infections. Trial Registration: ClinicalTrials.gov Identifier: NCT02142751.

Abdominal aortic endograft infection. A decade of experience and literature review. / Infección de endoprótesis aórtica abdominal. Experiencia de una década y revisión de la literatura.

INTRODUCTION: Aortic endograft infection is an infrequent but life-threatening complication after endovascular abdominal aortic repair (EVAR). There is no consensus on management of endograft infection and little evidence has been published in our country. Endograft explantation is considered the "gold standard" treatment whereas percutaneous or surgical perigraft and sac drainage associated to antibiotics should be considered and alternative therapy. METHODS: We carried out a retrospective and descriptive review of abdominal aortic endograft infections at our tertiary center (Hospital Universitario Cruces) during last ten years (2010-2019). RESULTS: We describe the clinical and microbiological characteristics of 10 EVAR infections, their management and outcomes. The incidence of graft infection after EVAR was 3%. The mean time to the clinical presentation of infection was 16.9 months (median 4.5 months). The microbiological diagnosis was reached in 100% of cases (predominance of gram-positive species). The overall mortality rate was 50% (although the survival rate was 100% after surgical drainage of the sac). CONCLUSIONS: Perigraft or aneurysm sac aspiration culture shows their diagnostic utility as microbiological diagnosis was reached in all cases despite of blood cultures being only positive in 50% of the samples. Surgical drainage and endograft preservation combined with antibiotherapy show remarkable results. The high heterogeneity in our case series makes difficult to offer general recommendations, thus far, a tailored approach to treatment is suggested.

Identification of CRF89_BF, a new member of an HIV-1 circulating BF intersubtype recombinant form family widely spread in South America.

Circulating recombinant forms (CRFs) contribute substantially to the HIV-1 pandemic. Among 105 CRFs described in the literature, 16 are BF intersubtype recombinants, most of South American origin, of which CRF12_BF is the most widely spread. A BF recombinant cluster identified in Bolivia was suggested to represent a new CRF_BF. Here we find that it belongs to a larger cluster incorporating 39 viruses collected in 7 countries from 3 continents, 22 of them in Spain, most from Bolivian or Peruvian individuals, and 12 in South America (Bolivia, Argentina, and Peru). This BF cluster comprises three major subclusters, two associated with Bolivian and one with Peruvian individuals. Near full-length genome sequence analyses of nine viruses, collected in Spain, Bolivia, and Peru, revealed coincident BF mosaic structures, with 13 breakpoints, 6 and 7 of which coincided with CRF12_BF and CRF17_BF, respectively. In a phylogenetic tree, they grouped in a clade closely related to these CRFs, and more distantly to CRF38_BF and CRF44_BF, all circulating in South America. These results allowed to identify a new HIV-1 CRF, designated CRF89_BF. Through phylodynamic analyses, CRF89_BF emergence was estimated in Bolivia around 1986. CRF89_BF is the fifth CRF member of the HIV-1 recombinant family related to CRF12_BF.

Second week methyl-prednisolone pulses improve prognosis in patients with severe coronavirus disease 2019 pneumonia: An observational comparative study using routine care data.

OBJECTIVE: To analyze the effects of a short course of methyl-prednisolone pulses (MP) during the second week of disease (week-2) in patients with severe coronavirus disease 2019 (COVID-19) pneumonia. METHODS: Comparative observational study using data collected from routine care at Hospital Universitario Cruces, Barakaldo, Bizkaia, Spain in patients with COVID-19 pneumonia. We compared patients who received week-2-MP (125-250 mg/d x3) with those who did not, with the end-points time to death and time to death or endotracheal intubation. RESULTS: We included 242 patients with COVID-19 pneumonia and elevated inflammatory markers at admission. Sixty-one patients (25%) received week-2-MP. Twenty-two patients (9%) died and 31 (12.8%) suffered death or intubation. The adjusted HRs for death and death or intubation for patients in the week-2-MP group were 0.35 (95%CI 0.11 to 1.06, p = 0.064) and 0.33 (95%CI 0.13 to 0.84, p = 0.020), respectively. These differences were specifically seen in the subcohort of patients with a SpO2/FiO2 at day 7 lower than 353 (adjusted HR 0.31, 95% CI 0.08 to 1.12, p = 0.073 and HR 0.34, 95%CI 0.12 to 0.94, p = 0.038, respectively) but not in patients with higher SpO2/FiO2. Patients receiving out-of-week-2-MP, non-pulse glucocorticoids or no glucocorticoids had an increased adjusted risk for both outcomes compared with week-2-MP group: HR 5.04 (95% CI 0.91-27.86), HR 10.09 (95% CI 2.14-47.50), HR 4.14 (95% CI 0.81-21.23), respectively, for death; HR 7.38 (95% CI 1.86-29.29), HR 13.71 (95% CI 3.76-50.07), HR 3.58 (95% CI 0.89-14.32), respectively, for death or intubation. These differences were significant only in the subgroup with low SpO2/FiO2. CONCLUSIONS: Week-2-MP are effective in improving the prognosis of patients with COVID-19 pneumonia with features of inflammatory activity and respiratory deterioration entering the second week of disease. The recognition of this high-risk population should prompt early use of MP at this point.

Role of age and comorbidities in mortality of patients with infective endocarditis.

PURPOSE: The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality. METHODS: Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015.Patients were stratified into three age groups:<65 years,65 to 80 years,and ≥ 80 years.The area under the receiver-operating characteristic (AUROC) curve was calculated to quantify the diagnostic accuracy of the CCI to predict mortality risk. RESULTS: A total of 3120 patients with IE (1327 < 65 years;1291 65-80 years;502 ≥ 80 years) were enrolled.Fever and heart failure were the most common presentations of IE, with no differences among age groups.Patients ≥80 years who underwent surgery were significantly lower compared with other age groups (14.3%,65 years; 20.5%,65-79 years; 31.3%,≥80 years). In-hospital mortality was lower in the <65-year group (20.3%,<65 years;30.1%,65-79 years;34.7%,≥80 years;p < 0.001) as well as 1-year mortality (3.2%, <65 years; 5.5%, 65-80 years;7.6%,≥80 years; p = 0.003).Independent predictors of mortality were age ≥ 80 years (hazard ratio [HR]:2.78;95% confidence interval [CI]:2.32-3.34), CCI ≥ 3 (HR:1.62; 95% CI:1.39-1.88),and non-performed surgery (HR:1.64;95% CI:11.16-1.58).When the three age groups were compared,the AUROC curve for CCI was significantly larger for patients aged <65 years(p < 0.001) for both in-hospital and 1-year mortality. CONCLUSION: There were no differences in the clinical presentation of IE between the groups. Age ≥ 80 years, high comorbidity (measured by CCI),and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in the <65-year group.

A case-control study of non-AIDS-defining cancers in a prospective cohort of HIV-infected patients. / Estudio caso-control de tumores no definitorios de sida en una cohorte prospectiva de pacientes infectados por el VIH.

INTRODUCTION: We present a case-control study of non-AIDS-defining cancers (NADCs) in a cohort of HIV-infected patients where we value the incidence, survival and prognostic factors of mortality. METHODS: All NADCs diagnosis conducted from 2007 to 2011 in 7 hospitals were collected prospectively, with a subsequent follow up until December 2013. A control group of 221 HIV patients without a diagnosis of cancer was randomly selected. RESULTS: Two hundred and twenty-one NADCs were diagnosed in an initial cohort of 7,067 HIV-infected patients. The most common were: hepatocellular carcinoma 20.5%, lung 18.7%, head and neck 11.9% and anal 10.5%. The incidence rate of NADCs development was 7.84/1,000 people-year. In addition to aging and smoking, time on ART (OR 1.11; 95% CI 1.05-1.17) and PI use (OR 1.72; 95% CI 1.0-2.96) increased the risk of developing a NADC. During follow-up 53.42% died, with a median survival time of 199.5 days. In the analysis of the prognostic factors of mortality the low values of CD4 at tumour diagnosis (OR 0.99; 95% CI 0.99-1.0; P=.033), and the previous diagnosis of AIDS (OR 2.06; 95% CI 1.08-3.92) were associated with higher mortality. CONCLUSIONS: Predictors of NADCs in our cohort were age, smoking, CD4 lymphocytes and time on ART. Mortality is high, with NADC risk factors being low CD4 count and previous diagnosis of AIDS.

Prediction of recurrent clostridium difficile infection at the bedside: the GEIH-CDI score.

Recurrence of Clostridium difficile infection (CDI) has major consequences for both patients and the health system. The ability to predict which patients are at increased risk of recurrent CDI makes it possible to select candidates for treatment with new drugs and therapies (including fecal microbiota transplantation) that have proven to reduce the incidence of recurrence of CDI. Our objective was to develop a clinical prediction tool, the GEIH-CDI score, to determine the risk of recurrence of CDI. Predictors of recurrence of CDI were investigated using logistic regression in a prospective cohort of 274 patients diagnosed with CDI. The model was calibrated using the Hosmer-Lemeshow test. The tool comprises four factors: age (70-79 years and ≥80 years), history of CDI during the previous year, direct detection of toxin in stool, and persistence of diarrhea on the fifth day of treatment. The functioning of the GEIH-CDI score was validated in a prospective cohort of 183 patients. The area under the ROC curve was 0.72 (0.65-0.79). Application of the tool makes it possible to select patients at high risk (>50%) of recurrence and patients at low risk (<10%) of recurrence. GEIH-CDI score may be useful for clinicians treating patients with CDI.

[First case report of catheter-related fungemia by Candida nivariensis in the Iberian Peninsula]. / Primer caso de fungemia asociada a catéter por Candida nivariensis en la Península Ibérica.

BACKGROUND: In recent years the incidence of candidemia caused by non-albicans Candida species has been increasing. Two cryptic species have been described within the Candida glabrata complex, Candida nivariensis and Candida bracarensis, which may be troublesome in laboratory identification and have lower susceptibility to fluconazole. AIMS: To describe the first isolation of C. nivariensis in the Iberian Peninsula from a patient suffering from a catheter-related fungemia. CASE REPORT: An 81-year-old man was hospitalized for surgical treatment of an intestinal fistula that was associated to a severe malnutrition. Cultures of the patient's central venous catheter tip and blood yielded white colonies in BD CHROMagar Candida(®) medium, which could not be identified by conventional microbiological methods. Although intravenous fluconazole was administered, blood cultures continued being positive 5 days later. The MIC values of the isolate were as follows: 1 µg/ml for amphotericin B, 0.015 µg/ml for anidulafungin, 0.125 µg/ml for caspofungin, 0.015 µg/ml for micafungin, 4 µg/ml for fluconazole, 0.25 µg/ml for itraconazole, 0.25 µg/ml for posaconazole, and 0.03 µg/ml for voriconazole. Antifungal treatment was changed to intravenous caspofungin for 2 weeks. The intestinal fistula was surgically treated. There was no evidence of relapse during the following month, and the patient was discharged. The isolate was identified as C. nivariensis based on DNA sequencing of the ITS regions of rRNA. CONCLUSIONS: C. nivariensis should be regarded as an emerging pathogen which requires molecular methods for a definitive identification. Our patient was successfully treated with caspofungin.