Identification to the species level and differentiation between strains of Aspergillus clinical isolates by automated repetitive-sequence-based PCR

A commercially available repetitive-sequence-based PCR (rep-PCR) DNA fingerprinting assay adapted to an automated format, the DiversiLab system, enables rapid microbial identification and strain typing. We explored the performance of the DiversiLab system as a molecular typing tool for 69 Aspergillus isolates (38 A. fumigatus, 15 A. flavus, and 16 A. terreus isolates) had been previously characterized by morphological analysis. Initially, 27 Aspergillus isolates (10 A. fumigatus, 9 A. flavus, and 8 A. terreus isolates) were used as controls to create a rep-PCR-based DNA fingerprint library with the DiversiLab software. Then, 42 blinded Aspergillus isolates were typed using the system. The rep-PCR-based profile revealed 98% concordance with morphology-based identification. rep-PCR-based DNA fingerprints were reproducible and were consistent for DNA from both hyphae and conidia. DiversiLab dendrogram reports correctly identified all A. fumigatus (n = 28), A. terreus (n = 8), and A. flavus (n = 6) isolates in the 42 blinded Aspergillus isolates. rep-PCR-based identification of all isolates was 100% in agreement with the contiguous internal transcribed spacer (ITS) region (ITS1-5.8S-ITS2) sequence-based identification of the respective isolates. Additionally, the DiversiLab system could demonstrate strain-level differentiation of A. flavus and A. terreus. Automated rep-PCR may be a time-efficient, effective, easy-to-use, novel genotyping tool for identifying and determining the strain relatedness of fungi. This system may be useful for epidemiological studies, molecular typing, and surveillance of Aspergillus species.     

Intravenous itraconazole for prophylaxis of systemic fungal infections in patients with acute myelogenous leukemia and high-risk myelodysplastic syndrome undergoing induction chemotherapy

BACKGROUND: Systemic fungal infections remain the leading cause of mortality in patients with newly diagnosed acute myelogenous leukemia (AML) and high-risk myelodysplastic syndrome (MDS). The objective of the current study was to determine whether intravenous itraconazole (i.v. ITRA) reduced the incidence of probable/proven fungal infections in this group of patients, and compare the results with those of a historic control group treated with fluconazole plus itraconazole capsules (F+I). METHODS: Patients with AML and high-risk MDS who underwent induction chemotherapy received 200 mg of i.v. itraconazole over 60 minutes every 12 hours during the first 2 days followed by 200 mg given i.v. once daily. RESULTS: One hundred patients were enrolled, 96 of whom were evaluable. Approximately 48% of the patients in the group of patients treated with i.v. ITRA as well as in the F+I group completed prophylaxis. Nine patients (9%) in the study group developed either proven/probable fungal infections (Candida glabrata in 5 patients, C. tropicalis in 1 patient, C krusei in 1 patient, and Fusarium in 2 patients) compared with 3 patients (4%) with proven fungal infection in the historic control group (C. tropicalis in 1 patient and Aspergillus in 2 patients). There were no significant differences noted between the two groups with regard to the percentage of patients who developed proven/probable or possible fungal infection as well as with regard to survival. These results also were obtained after adjusting for relevant prognostic factors (creatinine and bilirubin). The most common toxicity encountered with the use of i.v. ITRA was NCI Grade 3-4 hyperbilirubinemia (6%). CONCLUSIONS: Despite its theoretic advantages, the authors found no evidence that i.v. ITRA is superior to itraconazole capsules, at least when the latter is combined with fluconazole.     

Sequential exposure of Aspergillus fumigatus to itraconazole and caspofungin: evidence of enhanced in vitro activity

We investigated the in vitro activity of sequential itraconazole and caspofungin against 10 isolates of Aspergillus fumigatus. Previous exposure of A. fumigatus to itraconazole resulted in dose-dependent enhanced effects of caspofungin and vice versa. Our finding suggests a preferential role for azole-caspofungin sequential combinations and merits further in vivo investigation.     

What is the significance of an isolated positive cryptococcal antigen in the cerebrospinal fluid of cancer patients?

We evaluated the significance of an isolated positive cryptococcal antigen titer in the cerebrospinal fluid (CSF) of 12 cancer patients. In most of the cases, the test had a low titer, was frequently associated with an intracranial malignancy and was considered to represent a false-positive result. Hence, an isolated cryptococcal antigen in the CSF has an unclear clinical value and must be interpreted with caution.     

Liposomal amphotericin B versus the combination of fluconazole and itraconazole as prophylaxis for invasive fungal infections during induction chemotherapy for patients with acute myelogenous leukemia and myelodysplastic syndrome

BACKGROUND: Fungal infections are a major cause of morbidity and mortality in patients undergoing induction chemotherapy for acute myelogenous leukemia (AML) and myelodysplastic syndrome (MDS). The authors evaluated the efficacy and toxicity of liposomal amphotericin B (L-AmB) compared with a combination of fluconazole plus itraconazole (F+I) as prophylaxis in this setting. METHODS: Patients with newly diagnosed AML or high-risk MDS who were undergoing initial induction chemotherapy were randomized to receive either F+I (fluconazole 200 mg orally every 12 hours plus itraconazole tablets 200 mg orally every 12 hours) or L-AmB (3 mg/kg intravenously 3 times per week) in this prospective, open-label study. RESULTS: Seventy-two L-AmB-treated patients and 67 F+I-treated patients were enrolled in the study. Of these, 47% of patients completed antifungal prophylaxis without a change in therapy for proven or suspected fungal infection. Three patients in each arm developed a proven fungal infection. Twenty-three percent of the L-AmB-treated patients and 24% of the F+I-treated patients were changed to alternative antifungal therapy because of persistent fever (P value not significant). Nine percent of the L-AmB-treated patients developed pneumonia of unknown etiology compared with 16% of the F+I-treated patients (P value not significant). Increases in serum creatinine levels to > 2 mg/dL (20% for the L-AmB arm vs. 6% for the F+I arm; P = 0.012) and increases in serum bilirubin levels to > 2 mg/dL (43% vs. 22%, respectively; P = 0.021) were more common with L-AmB. Infusion-related reactions were noted in five L-AmB-treated patients. Responses to chemotherapy and induction mortality rates were similar for the two arms. CONCLUSIONS: L-AmB and F+I appear similar in their efficacy as antifungal prophylaxis during induction chemotherapy for patients with AML and MDS. L-AmB was associated with higher rates of increased serum bilirubin and creatinine levels.     

<Emphasis Type="Italic">BRCA1</Emphasis> and <Emphasis Type="Italic">BRCA2</Emphasis> mutations in a population-based study of male breast cancer

Background

The contribution of BRCA1 and BRCA2 to the incidence of male breast cancer (MBC) in the United Kingdom is not known, and the importance of these genes in the increased risk of female breast cancer associated with a family history of breast cancer in a male first-degree relative is unclear.

Methods

We have carried out a population-based study of 94 MBC cases collected in the UK. We screened genomic DNA for mutations in BRCA1 and BRCA2 and used family history data from these cases to calculate the risk of breast cancer to female relatives of MBC cases. We also estimated the contribution of BRCA1 and BRCA2 to this risk.

Results

Nineteen cases (20%) reported a first-degree relative with breast cancer, of whom seven also had an affected second-degree relative. The breast cancer risk in female first-degree relatives was 2.4 times (95% confidence interval [CI] = 1.4–4.0) the risk in the general population. No BRCA1 mutation carriers were identified and five cases were found to carry a mutation in BRCA2. Allowing for a mutation detection sensitivity frequency of 70%, the carrier frequency for BRCA2 mutations was 8% (95% CI = 3–19). All the mutation carriers had a family history of breast, ovarian, prostate or pancreatic cancer. However, BRCA2 accounted for only 15% of the excess familial risk of breast cancer in female first-degree relatives.

Conclusion

These data suggest that other genes that confer an increased risk for both female and male breast cancer have yet to be found.

     

Prolonged QT interval and cardiac arrhythmias in two neonates: sudden infant death syndrome in one case

Two neonates with arrhythmias and the long QT syndrome are described. The arrhythmias were detected in utero and both infants were apparently well after birth. The first infant, although well, had a bradycardia for the first 9 days of life. A normal heart rate was documented at 10 days but a prolonged QT interval was not appreciated on the ECG. He was discharged from hospital but died suddenly and unexpectedly 3 days later. A post-mortem examination failed to find a cause for his death which therefore fell into the category of the sudden infant death syndrome (SIDS). A retrospective analysis of the perinatal electrocardiogram showed a probable junctional rhythm with 2:1 conduction to the ventricle; the QT interval was prolonged at 0.52 seconds (QTC = 0.63). The second infant had a QT interval of 0.52 seconds (QTC = 0.54) and frequent ventricular premature beats on a 24-hour electrocardiogram. She was treated with propranolol and remains well 2 years later. Sudden infant death has often been described in the siblings of children with the long QT syndrome and one other report described a case of SIDS which was said to have had a prolonged QT interval on the perinatal ECG. This report, however, provides unquestionable evidence, in one case, of an association between the long QT syndrome and SIDS.     

The use of 18F-fluorodeoxyglucose positron emission tomography for the diagnosis and management of invasive mould infections.

There is limited information on the utility of 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) for the diagnosis and management of invasive mould infections (IMIs). We retrospectively evaluated patients with IMIs who underwent FDG-PET in our institution (n = 13; December 1999 to April 2004), and reviewed the available literature (n = 9). In 16 non-neutropenic patients with available FDG-PET imaging studies (11 from our institution), FDG-PET revealed an occult IMI site (n = 3; 2 unidentified CNS involvement) and was helpful in guiding the duration of treatment (n = 8). Prospective evaluation of the role of FDG-PET in the work-up and management of IMIs is needed.     

An analysis of eccentric photo refraction

The optics of eccentric photo refraction are analysed. The variation of photo refractive lunula area with refractive error, pupil size, flash eccentricity and camera aperture were calculated using a model eye. Measurements from photographs of paraxial (eccentric) photo refraction of model eyes show that a good agreement exists between theory and experiment over a range of refractive errors from — 10 D to +10 D. Calculations were also made for a standard reduced eye. The optimal set-up for measuring refractive error accurately over a wide range of refractive states is discussed, as are the problems which arise from non-central fixation.     

Pineal germinoma: MR imaging

Magnetic resonance (MR) imaging characteristics of pineal germinomas are described in seven patients imaged with MR and computed tomography (CT). In patients with symptoms of an enlarging process in the quadrigeminal plate cistern, MR imaging was as sensitive as CT scanning in detecting the mass. MR imaging did not detect a normal-sized, calcified neoplastic gland. Germinoma, germinoma with embryonal cell carcinoma elements, and pineoblastoma demonstrated different MR signal characteristics. Although direct coronal and sagittal MR images were useful in defining the relationship of the tumor to the posterior third ventricle, Sylvian aqueduct, and vein of Galen, the ease, rapidity, and sensitivity of CT scanning suggest that CT should remain the modality of choice for initial evaluation and screening of the pineal region, especially in the younger pediatric population, in whom detection of calcification may provide the only clue of an abnormality.