Caspar J. Hodiamont

Multiple-azole-resistant Aspergillus fumigatus osteomyelitis in a patient with chronic granulomatous disease successfully treated with long-term oral posaconazole and surgery

We describe a patient with chronic granulomatous disease and proven Aspergillus fumigatus osteomyelitis of the midfoot, while receiving itraconazole-prophylaxis. The isolate proved resistant to itraconazole as well as voriconazole, and showed reduced susceptibility to posaconazole. Although molecular analysis demonstrated the presence of a 53 base pair tandem repeat in the promoter region for cyp51A, i.e., the gene coding for the target enzyme of the azole antifungals, there were no mutations in the cyp51A gene. Since transformation of the promoter region into wild-type strains did not result in an azole resistant phenotype, a yet unknown mutation was suspected. The patient was treated with extensive surgery and two weeks of caspofungin therapy, followed by one year of posaconazole therapy. He made a complete recovery and did not experience any side effects. Long-term posaconazole proved to be a safe and effective treatment for multi-azole resistant A. fumigatus osteomyelitis in this immunocompromised patient.

Performance of Kiestra Total Laboratory Automation Combined with MS in Clinical Microbiology Practice

Background Microbiological laboratories seek technologically innovative solutions to cope with large numbers of samples and limited personnel and financial resources. One platform that has recently become available is the Kiestra Total Laboratory Automation (TLA) system (BD Kiestra B.V., the Netherlands). This fully automated sample processing system, equipped with digital imaging technology, allows superior detection of microbial growth. Combining this approach with matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MS) (Bruker Daltonik, Germany) is expected to enable more rapid identification of pathogens. Methods Early growth detection by digital imaging using Kiestra TLA combined with MS was compared to conventional methods (CM) of detection. Accuracy and time taken for microbial identification were evaluated for the two methods in 219 clinical blood culture isolates. The possible clinical impact of earlier microbial identification was assessed according to antibiotic treatment prescription. Results Pathogen identification using Kiestra TLA combined with MS resulted in a 30.6 hr time gain per isolate compared to CM. Pathogens were successfully identified in 98.4% (249/253) of all tested isolates. Early microbial identification without susceptibility testing led to an adjustment of antibiotic regimen in 12% (24/200) of patients. Conclusions The requisite 24 hr incubation time for microbial pathogens to reach sufficient growth for susceptibility testing and identification would be shortened by the implementation of Kiestra TLA in combination with MS, compared to the use of CM. Not only can this method optimize workflow and reduce costs, but it can allow potentially life-saving switches in antibiotic regimen to be initiated sooner.

Species-Directed Therapy for Leishmaniasis in Returning Travellers: A Comprehensive Guide

Background Leishmaniasis is increasingly reported among travellers. Leishmania species vary in sensitivity to available therapies. Fast and reliable molecular techniques have made species-directed treatment feasible. Many treatment trials have been designed poorly, thus developing evidence-based guidelines for species-directed treatment is difficult. Published guidelines on leishmaniasis in travellers do not aim to be comprehensive or do not quantify overall treatment success for available therapies. We aimed at providing comprehensive species-directed treatment guidelines. Methodology/Principal Findings English literature was searched using PubMed. Trials and observational studies were included if all cases were parasitologically confirmed, the Leishmania species was known, clear clinical end-points and time points for evaluation of treatment success were defined, duration of follow-up was adequate and loss to follow-up was acceptable. The proportion of successful treatment responses was pooled using mixed effects methods to estimate the efficacy of specific therapies. Final ranking of treatment options was done by an expert panel based on pooled efficacy estimates and practical considerations. 168 studies were included, with 287 treatment arms. Based on Leishmania species, symptoms and geography, 25 clinical categories were defined and therapy options ranked. In 12/25 categories, proposed treatment agreed with highest efficacy data from literature. For 5/25 categories no literature was found, and in 8/25 categories treatment advise differed from literature evidence. For uncomplicated cutaneous leishmaniasis, combination of intralesional antimony with cryotherapy is advised, except for L. guyanensis and L. braziliensis infections, for which systemic treatment is preferred. Treatment of complicated (muco)cutaneous leishmaniasis differs per species. For visceral leishmaniasis, liposomal amphotericin B is treatment of choice. Conclusions/Significance Our study highlights current knowledge about species-directed therapy of leishmaniasis in returning travellers and also demonstrates lack of evidence for treatment of several clinical categories. New data can easily be incorporated in the presented overview. Updates will be of use for clinical decision making and for defining further research.

Imported leishmaniasis in the Netherlands from 2005 to 2012: epidemiology, diagnostic techniques and sequence-based species typing from 195 patients

Leishmaniasis is an imported disease in the Netherlands. We report data for the period between 2005 and 2012, on clinical presentation, country where leishmaniasis was acquired, and causative species, for 195 civilian and military patients who had travelled abroad. Most patients were affected by cutaneous leishmaniasis (CL) (n=185 patients), while visceral leishmaniasis (VL) (n=8 patients) and mucocutaneous leishmaniasis (n=2 patients) were less frequently observed. All VL patients had been infected in Europe. CL was mainly acquired in Afghanistan, Surinam, Morocco and Spain. The majority of CL patients consisted of military personnel (55%, 102/185), 78 of whom had been infected during an outbreak in Afghanistan. Parasitological diagnosis was made by a combination of polymerase chain reaction (PCR), microscopy and culture. Compared to a standard of parasitological proof by any method other than the one under consideration, sensitivities of the individual methods ranged from 73% to 98%. Microscopy was least sensitive, but is fast and cheap. Mini-exon repeat PCR combines high sensitivity and specificity, and allows differentiation between species by sequencing of the PCR product. Eight different species or species complexes were identified, allowing species-specific therapy. Four patients proved infected with Leishmania naiffi, a hitherto rarely described cause of leishmaniasis. In comparison to previous decennia, an increase in cutaneous leishmaniasis was observed in our hospital, both in civilian and military patients who had travelled abroad. This calls for increased awareness among clinicians, availability of diagnostic tests and species-specific treatment guidelines in non-endemic countries.

Diagnosis and management of aspergillosis in the Netherlands: a national survey

A survey of diagnosis and treatment of invasive aspergillosis was conducted in eight University Medical Centers (UMCs) and eight non‐academic teaching hospitals in the Netherlands. Against a background of emerging azole resistance in Aspergillus fumigatus routine resistance screening of clinical isolates was performed primarily in the UMCs. Azole resistance rates at the hospital level varied between 5% and 10%, although rates up to 30% were reported in high‐risk wards. Voriconazole remained first choice for invasive aspergillosis in 13 out of 16 hospitals. In documented azole resistance 14 out of 16 centres treated patients with liposomal amphotericin B.

Dengue in travellers: applicability of the 1975–1997 and the 2009 WHO classification system of dengue fever

Objectives  The aim of this study was to assess the applicability and benefits of the new WHO dengue fever guidelines in clinical practice, for returning travellers.

Determinants of gentamicin concentrations in critically ill patients: a population pharmacokinetic analysis

When treating critically ill patients with gentamicin for severe infection, peak concentrations (Cmax) determine clinical efficacy and trough concentrations (Cmin) determine toxicity. Despite administration of body weight-standardised starting doses, a wide range of Cmax is generally observed. Furthermore, in therapeutic drug monitoring, several measures of renal function are used to predict appropriate Cmin and gentamicin dosing intervals, but the most accurate predictor is not known. This study aimed to quantify the impact of several patient parameters on gentamicin Cmax values and to determine which measure of renal function best predicts gentamicin clearance (CL). Clinical data and serum gentamicin levels were retrospectively collected from all critically ill patients treated with gentamicin at our intensive care unit between 1 January and 30 June 2011. Data were analysed using non-linear mixed-effects modelling (NONMEM v.7.1.2). A two-compartmental model was developed based on 303 gentamicin concentration-time data from 44 critically ill patients. Serum albumin levels explained 25% of interindividual variability in the volume of distribution (Vd). Creatinine clearance calculated from the creatinine concentration in a 6-h urine portion (CalcCLCr) resulted in acceptable estimation of gentamicin CL, whilst serum creatinine (SCr) and creatinine clearance estimated by the Cockcroft-Gault formula (CGCLCr) overestimated gentamicin CL and therefore underestimated Cmin. In conclusion, low albumin concentrations resulted in a larger Vd and lower Cmax of gentamicin. These results suggest that use of a higher gentamicin starting dose in critically ill patients with hypoalbuminaemia may prevent underdosing. Urinary CalcCLCr is a better predictor of Cmin than SCr or CGCLCr.

Pleurodynia caused by an echovirus 1 brought back from the tropics.

A 31 year-old woman presented with acute pain on the left side of the thorax and abdomen, radiating to the back together with fever, after she had returned from traveling in Southeast Asia. Except for pleural friction rub auscultated on the left hemithorax, no physical abnormalities were detected. We diagnosed a classical course of Bornholm disease, caused by an echovirus type 1. While described as a classical pathogen causing Bornholm disease, this genotype has not been reported frequently in Surveillance data in the Western World.

Population Pharmacokinetics and Dosing Considerations for Gentamicin in Newborns with Suspected or Proven Sepsis Caused by Gram-Negative Bacteria.

ABSTRACT The aim of this study was to describe the population pharmacokinetics (PK) of gentamicin in neonates with suspected or proven Gram-negative sepsis and determine the optimal dosage regimen in relation to the bacterial MICs found in this population. Data were prospectively collected between October 2012 and January 2013 in the Neonatal Intensive Care Unit (NICU) at the Academic Medical Center (AMC), Amsterdam, The Netherlands. A single nonlinear mixed-effects regression analysis (NONMEM) was performed to describe the population PK of gentamicin. Dosage regimens based upon gestational age (GA) were generated using Monte Carlo simulations with the final model. Target values were based on the MIC distribution in our patient population. In total, 136 gentamicin concentrations from 65 (pre)term neonates were included. The PK was best described by an allometric 2-compartment model with postmenstrual age (PMA) as a covariate on clearance (Cl). The MIC distribution (median, 0.75 [range, 0.5 to 1.5] mg/liter) justified a gentamicin target peak concentration of 8 to 12 mg/liter. This study describes the PK of gentamicin in (pre)term neonates. Dosage regimens of 5 mg/kg of body weight every 48 h, 5 mg/kg every 36 h, and 5 mg/kg every 24 h for patients with GAs of <37 weeks, 37 to 40 weeks, and ≥40 weeks, respectively, are recommended.

Comparison of the PRNT and an immune fluorescence assay in yellow fever vaccinees receiving immunosuppressive medication

BACKGROUND The 17D-yellow fever (YF) vaccination is considered contraindicated in immune-compromised patients; however, accidental vaccination occurs. In this population, measuring the immune response is useful in clinical practice. METHODS In this study we compare two antibody tests (the Immune Fluorescence Assay and the Plaque Reduction Neutralization Test) in a group of Dutch immune-compromised travellers with a median of 33 days (IQR [28-49]) after primary YF vaccination. RESULTS We collected samples of 15 immune-compromised vaccinees vaccinated with the 17D yellow fever vaccine between 2004 and 2012. All samples measured in the plaque reduction neutralization test yielded positive results (>80% virus neutralization with a 1:10 serum dilution). Immune Fluorescence Assay sensitivity was 28% (95% CI [0.12-0.49]). No adverse events were reported. CONCLUSIONS All immune-compromised patients mounted an adequate response with protective levels of virus neutralizing antibodies to the 17-D YF vaccine. No adverse effects were reported. Compared to the plaque reduction neutralization test, the sensitivity of the Immune Fluorescence Assay test was low. Further research is needed to ascertain that 17D vaccination in immune-compromised patients is safe.