Triazole resistance in Aspergillus fumigatus: recent insights and challenges for patient management.

BACKGROUND: Triazole resistance in Aspergillus fumigatus is widespread and threatens first-line triazole therapy in patients with Aspergillus diseases. OBJECTIVES: To give an overview of the microbiology, epidemiology and clinical significance of triazole resistance in aspergillosis. SOURCES: PubMed search for articles on resistance in Aspergillus species. CONTENT: Triazoles are not mutagenic but select resistance when spontaneous mutations occur that are better able to proliferate in the triazole-containing environment. The major target for resistance mutations involves the Cyp51A gene, encoding an enzyme involved in cell wall synthesis. Triazole-resistance selection environments include patient treatment and organic matter containing triazole fungicide residues. Reported resistance frequencies vary widely between countries and hospitals, and resistance significantly complicates the diagnosis and treatment of Aspergillus diseases. Cultures may harbour various resistance phenotypes and multiple colonies must be analysed to detect resistance. PCR tests have become available for resistance detection in culture-negative patients, but show limited sensitivity. Individuals with triazole-resistant invasive aspergillosis have a 21% higher day-42 mortality compared with triazole-susceptible infection, and to prevent excess mortality resistant cases require first-line therapy that covers resistance. The recent ESCMID-ECMM-ERS Aspergillus guideline recommends resistance testing in A. fumigatus and local resistance surveillance. If resistance rates exceed 10% liposomal amphotericin B or triazole and echinocandin first-line therapy should be considered. IMPLICATIONS: Triazole resistance significantly complicates the management of aspergillosis and multidisciplinary research from a 'One-health' perspective is required to retain the triazole class for medical use.

Epidemiology of invasive aspergillosis and triazole-resistant Aspergillus fumigatus in patients with haematological malignancies: a single-centre retrospective cohort study.

Objectives: To investigate the epidemiology and clinical relevance of triazole resistance among patients undergoing treatment for haematological malignancies who are at risk of invasive aspergillosis (IA). Methods: This was a retrospective cohort study for which the records of consecutive patients given chemotherapy for AML or myelodysplastic syndrome (MDS) or who had received an allogeneic HSCT from 2006 to 2012 were reviewed for IA. Triazole resistance was detected by the VIPcheck™ screening method and confirmed by determining the MIC by EUCAST methodology. Results: A total of 432 patients were included, comprising 182 (42.1%) patients who had undergone chemotherapy for AML or MDS, and 250 (57.9%) patients who had undergone an allogeneic HSCT. Probable or proven IA was diagnosed in 36 cases (8.3%, 95% CI 6.0%-11.4%). Of these, 12 (33.3%) were based on recovery of Aspergillus fumigatus from sputum, bronchoalveolar lavage or biopsy, and triazole resistance was found in 2 instances. A. fumigatus was also recovered from one or more specimens from 13 patients without probable or proven IA. Triazole resistance was documented for three patients. The survival rate of patients with IA caused by voriconazole-resistant isolates could not be assessed. Conclusions: The overall frequency of voriconazole-resistant IA among patients at high risk was low. However, the rate of triazole resistance may have been underestimated by the low detection rate based on recovery of A. fumigatus. Alternative diagnostic tests, such as PCR-based assays, may prove better at detecting IA due to triazole-resistant A. fumigatus.

Screening for Coxiella burnetii seroprevalence in chronic Q fever high-risk groups reveals the magnitude of the Dutch Q fever outbreak.

The Netherlands experienced an unprecedented outbreak of Q fever between 2007 and 2010. The Jeroen Bosch Hospital (JBH) in 's-Hertogenbosch is located in the centre of the epidemic area. Based on Q fever screening programmes, seroprevalence of IgG phase II antibodies to Coxiella burnetii in the JBH catchment area was 10·7% [785 tested, 84 seropositive, 95% confidence interval (CI) 8·5-12·9]. Seroprevalence appeared not to be influenced by age, gender or area of residence. Extrapolating these data, an estimated 40 600 persons (95% CI 32 200-48 900) in the JBH catchment area have been infected by C. burnetii and are, therefore, potentially at risk for chronic Q fever. This figure by far exceeds the nationwide number of notified symptomatic acute Q fever patients and illustrates the magnitude of the Dutch Q fever outbreak. Clinicians in epidemic Q fever areas should be alert for chronic Q fever, even if no acute Q fever is reported.

Chronic Q fever: review of the literature and a proposal of new diagnostic criteria.

A review was performed to determine clinical aspects and diagnostic tools for chronic Q fever. We present a Dutch guideline based on literature and clinical experience with chronic Q fever patients in The Netherlands so far. In this guideline diagnosis is categorized as proven, possible or probable chronic infection based on serology, PCR, clinical symptoms, risk factors and diagnostic imaging.

[Two patients with mumps]. / Twee patiënten met de bof.

Two patients, men aged 17 and 19 years respectively, were admitted with parotitis epidemica and orchitis caused by mumps. The second patient also had meningitis. PCR analysis revealed that, in both cases, the causative agentwas a mumps virus that was genetically related to a wild-type virus responsible for an outbreak in Singapore. This viral strain was also responsible for a mumps outbreak at Hotel School The Hague in September 2004. Both patients were not fully vaccinated. Both patients were from regions in which clustering of patients with clinical signs of mumps has been seen. Interestingly, a number of patients with confirmed mumps had been fully vaccinated. Possible explanations for the increase in mumps cases include low vaccination and immunity levels, primary and secondary vaccine failure and the emergence of genetically disparate mumps viruses.

[Hoarseness in a recent visitor to the tropics through infection of the larynx by Histoplasma capsulatum]. / Heesheid bij een tropenganger door infectie van de larynx met Histoplasma capsulatum.

A 58-year-old man presented with hoarseness and a sore throat for the previous 3 months, which were caused by a laryngeal infection with the fungus Histoplasma capsulatum. He had been infected during a stay in Indonesia. Both his hoarseness as well as the Histoplasma antigen titres in serum responded to therapy with itraconazol. H. capsulatum is found in tropical and subtropical areas worldwide, but infections are most commonly reported from the south of the United States of America. If not asymptomatic, the disease most often presents with pulmonary symptoms. A histoplasmosis presenting as a laryngeal infection is relatively uncommon and can be mistaken for papillomatosis or carcinoma. The diagnosis can be made by microscopy and culture of the fungus; an antigen test is available in the United States.

[Thyrotoxic periodic paralysis: case report (author's transl)]. / Un cas de paralysie périodique thyrotoxique.

Boy 19, french -- Attacks of hypokaliemic flaccid tetraplegia in 1972 -- 4 months later thyreotoxicosis -- Disappearance of neurologic symptoms and euthyroid condition after carbimazole. Relapse 5 years later of concomitant thyreotoxicosis, hypokaliemic tetraplegia attacks and lower limbs myalgias. Normal conventional and enzymatic light histology of quadriceps. Anomalies of membraneous system (T system and sarcoplasmic reticulum) on electron microscopy -- subtotal thyroidectomy -- hormonal and neurologic total recovery. Caucasoid erythrocyte and HLA groups.