Matrix-assisted laser desorption/ionisation time-of-flight (MALDI-TOF) mass spectrometry as a tool for rapid diagnosis of potentially toxigenic Corynebacterium species in the laboratory management of diphtheria-associated bacteria

The rapid identification of the potentially toxigenic Corynebacterium species, C. diphtheriae, C. ulcerans and C. pseudotuberculosis is essential for diagnosis and treatment of diphtheria and diphtheria-like diseases. We used matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDIT-OF MS) in comparison with classical microbiological and molecular methods on 116 Corynebacterium strains. All 90 potentially toxigenic Corynebacterium strains collected by the German National Consiliary Laboratory on Diphtheria in a period of more than ten years were correctly identified by MALDI-TOF MS. We propose an algorithm for fast and reliable diagnosis of diphtheria incorporating MALDI-TOF MS, real-time tox PCR and Elek testing.

Single-nucleotide polymorphism in the SCCmec-orfX junction distinguishes between livestock-associated MRSA CC398 and human epidemic MRSA strains

A number of real-time PCR assays for direct detection of methicillinresistant (MRSA) in clinical specimens are targeting staphylococcal cassette chromosome mec (SCCmec) right extremity sequences and the S. aureus chromosomal orfX gene sequences located to the right of the SCCmec integration site. When testing 184 MRSA strains of human and animal origin from geographically distinct locations, we identified several characteristic single-nucleotide polymorphisms (SNPs) within the SCCmec-orfX junction of livestock-associated (LA) MRSA CC398 which serve as suitable strain markers for screening purposes. Within an assay time of 60 minutes and an additional 10 minutes for the melting curve analysis, all MRSA CC398 isolates were correctly identified by their characteristic T(m) value in the commercial LightCycler MRSA Advanced test. Studies to confirm the diagnostic accuracy of the SNP-based strain identification assay with a larger collection of clinical and LA-MRSA strains are ongoing.

Single-nucleotide polymorphism in the SCCmec-orfX junction distinguishes between livestock-associated MRSA CC398 and human epidemic MRSA strains

A number of real-time PCR assays for direct detection of methicillin-resistant Staphylococcus aureus (MRSA) in clinical specimens are targeting staphylococcal cassette chromosome mec (SCCmec) right extremity sequences and the S. aureus chromosomal orfX gene sequences located to the right of the SCCmec integration site. When testing 184 MRSA strains of human and animal origin from geographically distinct locations, we identified several characteristic single-nucleotide polymorphisms (SNPs) within the SCCmec-orfX junction of livestock-associated (LA) MRSA CC398 which serve as suitable strain markers for screening purposes. Within an assay time of 60 minutes and an additional 10 minutes for the melting curve analysis, all MRSA CC398 isolates were correctly identified by their characteristic Tm value in the commercial LightCycler MRSA Advanced test. Studies to confirm the diagnostic accuracy of the SNP-based strain identification assay with a larger collection of clinical and LA-MRSA strains are ongoing.

Preliminary safety and effectiveness of bevacizumab (BV) based treatment in subpopulations of patients (pts) with non-small cell lung cancer (NSCLC) from the ARIES study: A bevacizumab (BV) treatment observational cohort study (OCS)

8040

Background: Phase III trials have shown that bevacizumab (Avastin, BV), an anti-VEGF monoclonal antibody, prolongs progression-free and overall survival in advanced NSCLC pts. To further define clinical outcomes associated with BV treatment among a broader population of NSCLC pts in a real-world setting, the ARIES OCS was initiated. Pt populations in OCSs are often more reflective of pts encountered in practice, permitting examination of treatment benefit and toxicity in subgroups that might be too small for study in traditional randomized controlled trials (RCTs). The NSCLC cohort in ARIES will assess clinical outcomes in the overall cohort as well as subpopulations such as the elderly, pts with poor PS or pts on concurrent anticoagulants (AC). Methods: Pts with advanced NSCLC whose 1st-line therapy includes BV may enroll. 257 sites are enrolling pts; total accrual of 2000 pts is expected. There are no protocol-specified treatments or assessments. Data is collected at baseline (BL) then quarterly, including targeted adverse events (AEs) and BV-related serious AEs. Clinical outcomes will be descriptively summarized by baseline characteristics. Multivariate analyses will be conducted if cohort size is sufficient. Results: As of 9/15/08, 1518 NSCLC pts have enrolled. Median F/U is 7.5 mos. Key BL characteristics: 20% ≥75 yrs; 67% adenocarcinoma; 10% ECOG ≥2; 8% brain metastasis; 5% therapeutic AC. The most common 1st-line chemotherapy regimen was carboplatin/paclitaxel (64%). Key safety outcomes and cohort size of subpopulations are in the Table . Conclusions: The safety of BV in subpopulations of pts in ARIES (elderly pts, pts with ECOG PS ≥2, with brain mets at BL, or on therapeutic AC) is generally consistent with safety results from RCTs. Updated outcomes analyses will be presented at the meeting for >1600 pts and subpopulations.

[Table: see text]

[Table: see text]

Development of cavitation while on bevacizumab (BV) therapy in patients (pts) with non-small cell lung cancer (NSCLC): Results from ARIES—A bevacizumab (BV) treatment observational cohort study (OCS)

e19045

Background: BV (Avastin), an anti-VEGF monoclonal antibody, prolongs progression-free and overall survival in advanced NSCLC pts. Severe (≥grade 3) pulmonary hemorrhage (sPH) is a rare but serious event that has been associated with BV-based therapy in phase 3 trials (rate of 2–4%). Potential risk factors include squamous histology, prior history of hemoptysis, and presence of tumor cavitation. Rates of baseline (BL) cavitation in NSCLC pts and development of cavitation on BV therapy are unknown. Pts in ARIES, an OCS of approximately 2,000 pts with NSCLC, had BL scans assessed for tumor cavitation. A substudy of approximately 250 pts also had follow-up scans to analyze the likelihood of developing cavitation on BV therapy. For the entire ARIES population, any pt developing sPH is assessed for tumor cavitation. Methods: Pts at specified ARIES sites submitted on-treatment CT scans to an independent review facility (IRF), in addition to BL scans. Evaluable pts had measurable disease at BL and at least one-post-BL scan. Correlations between cavitation (pre-existing or developing on-study) and clinical, tumor and treatment characteristics are evaluated using a chi-squared test or t-test. Incidence of sPH based on cavitation status will be assessed using Fisher's exact test. Results: As of 9/15/08, 210 pts had a post-BL CT scan reviewed by the IRF. Of these pts, 171 had measurable tumors at BL. For the 171 pt cohort: median F/U is 9.2 m; 99% have ≥1 quarterly update. Key BL characteristics for the substudy and overall cohorts, respectively, include: 44% vs 51% ≥65 yrs; 67% vs 67% adenocarcinoma; 6% vs 5% therapeutic AC. BL radiographic features: 41% vs 39% presence of central tumor; 13% vs 15% presence of cavitation. In substudy pts, there is 1 sPH to date in a pt without baseline cavitation. Conclusions: sPH is a rare, potentially serious event in pts with NSCLC receiving BV. Whether cavitation (BL or developing on-treatment) is associated with an increased risk of sPH has not been defined. The final analysis of an ARIES Lung substudy assessing on-study development of cavitation and association with sPH will be presented at the meeting.

[Table: see text]

SARS - Pandemie und Emerging Disease

The SARS-epidemic of 2002/2003 with worldwide 8.096 cases and 774 fatalities was the first pandemia of the 21^st century. SARS, the severe acute respiratory syndrome, arose in southern China and spread from Southeast-Asia finally over all five continents. It caused heavy pneumonia with pulmonal failure and enteric involvement in man. The causative agent was a novel coronavirus (SARS-CoV), which was transmitted from bats to small carnivores and from them to man. The mutations of the viral receptor gene thus allowed the infection of man and the transmission from man to man. The SARS-pandemia can therefore be regarded as a model of an emerging disease.

Genetic modification of T cell clones to improve the safety and efficacy of adoptive T cell therapy

Our laboratory has developed methods to isolate human antigen-specific cytolytic CD8+ T cell clones and to expand such clones in vitro to numbers sufficient for T cell therapy of human diseases. Studies in immunocompromised bone marrow transplant patients at high risk for disease associated with cytomegalovirus have demonstrated that administration of more than 10(9) CD8+ T cell clones is safe and can effectively reconstitute a deficient human immune response. Our laboratory is applying this strategy of adoptive therapy to the treatment of human cancer, starting with the subset of patients with Hodgkin's disease who show expression of proteins encoded by the Epstein-Barr virus in their malignant Reed-Sternberg cells. The development of efficient systems such as retroviral vectors for the introduction of genes into primary cells has made it possible to consider overcoming some of the limitations of the effector T cells that normally mediate response to an antigen. Our laboratory is attempting to modify T cell clones by the introduction of genes before transfer as a means to improve the safety and/or efficacy of T cell therapy.

Pulmonary radiological characteristics in patients with HIV infection at the time of highly active antiretroviral therapy (HAART)

OBJECTIVE

To report on radiological and epidemiological characteristics of pulmonary disease in patients with HIV infection in times of highly active antiretroviral therapy (HAART).

METHODS

Clinical data of 130 HIV infected adults with acute pulmonary symptoms were compared with findings in chest radiography (n = 130) and computed tomography (CT, n = 42). Presence and distribution of consolidation, interstitial changes, pleural effusion, and adenopathy were evaluated. Results were compared to findings from sputum, bronchoalveolar lavage, transbronchial biopsy, or empirical therapy results.

RESULTS

48% of patients presented pathologic findings. Overall sensitivity for the detection of pulmonary involvement was 0.87 (chest radiography) vs. 0.97 (CT). Disease specific sensitivity was 0.33 compared to 0.70. Bacterial pneumonia (BP, n = 26, 20%) was the most frequent diagnosis, followed by pneumocystis jiroveci pneumonia (PJP, n = 17, 13%), mycobacterium avium complex (MAC, 6%), Kaposi's sarcoma and lymphoma (KS and NHL, each 4%), fungal pneumonia (2%), and tuberculosis (TBC, 1%). Focal pulmonary infiltration was predominantly present in BP (50%, n = 13). Reticular (35%; n = 6) and micronodular (35%; n = 6) infiltration were predominantly found in PJP.

CONCLUSIONS

Despite HAART, lung involvement is still common. Only contrast-enhanced computed tomography shows an acceptable disease-specific sensitivity. In unclear cases, CT should be performed.

NCCTG phase II trial of bevacizumab, gemcitabine, oxaliplatin in patients with metastatic pancreatic adenocarcinoma

4113

Background: The combination of gemcitabine and oxaliplatin (GemOx) is a highly active regimen in pancreatic cancer. A recent study with the biologic agent, bevacizumab, and gemcitabine has also demonstrated significant activity. A phase II study is ongoing to evaluate whether combining an active cytotoxic doublet with an effective targeted agent improves 6-month survival and is tolerable in previously untreated patients (pts) with metastatic pancreas cancer. Methods: Treatment consists of gemcitabine 1000 mg/m2 IV over 100 minutes and bevacizumab 10 mg/kg IV given on day 1 and 15; oxaliplatin 100 mg/m2 IV is given on day 2 and 16. A treatment cycle consists of 28 days. Eligibility includes: no prior chemotherapy, ECOG PS 0–2, bili < 2× UNL, AST < 5× UNL. Pts with stable full-dose anticoagulation are eligible. Bevacizumab specific exclusions include no recent stroke, heart attack, embolus, tumor invasion or significant proteinuria. CT scans are obtained every 2 cycles. Treatment continues until disease progression, toxicity or patient refusal. Results: Sixty-three patients of a planned 75 were enrolled from 7/05 to 1/06; 2 cycles of toxicity data are available on 31 of the first 32 consecutive pts. The overall grade 3+ toxicity rate is 52% (16/31); more specifically, the grade 3 toxicities were 42% (13/31) and the grade 4 rate is 10% (3/31). Grade 3 adverse events are nausea (4), vomiting (4), alk phos (3), dehydration (3), thrombosis (2), leukopenia (2), neutropenia (4), abdominal pain (2), hypokalemia (4), and one each of the following: anorexia, low consciousness, pneumonia, rectal pain, diarrhea, and proctitis. There was one patient death due to cerebral ischemia (grade 5: 1/31 or 3%). Conclusions: Early assessment of toxicity in this trial reveals a reasonably tolerable regimen. Addition of bevacizumab to GemOx appears to have grade 3/4 toxicity rates similar to historical observations (ECOG 6201). Toxicity data for all patients, after at least 2 cycles of treatment, will be presented.

[Table: see text]