Targeted next-generation sequencing using a multigene panel in myeloid neoplasms: Implementation in clinical diagnostics.

INTRODUCTION: Detection of mutations in patients with myeloid neoplasms (MNs) has shown great potential for diagnostic and prognostic purposes. Next-generation sequencing (NGS) is currently implemented for the diagnostic profiling of the four major MN subgroups. METHODS: First, we validated the targeted NGS approach using the TruSight Myeloid panel. Next, we screened 287 patients with a clinical suspicion of MN and 61 follow-up patients with documented MN. RESULTS: Validation of the NGS workflow resulted in maximal precision, accuracy, sensitivity, and specificity for gene variants with an allele frequency of at least 5% and a minimal read depth of 300. In our diagnostic screen, we identified at least one somatic mutation in 89% of patients with proven MN. Of the 155 newly diagnosed MN cases, 126 (81%) showed at least one mutation, confirming clonality. Moreover, the co-occurrence of mutated genes in the different MN subentities facilitates their classification and justifies the diagnostic use of a pan-myeloid panel. Furthermore, several of these mutations provide additional prognostic information independently of traditional prognostic scoring systems. CONCLUSION: Pan-myeloid targeted NGS fits elegantly in the routine diagnostic approach of MNs allowing for an improved diagnosis, subclassification, and prognosis.

Alpha-1-Fetoprotein (AFP): international proficiency study with different test systems.

BACKGROUND: The present proficiency study aimed to elucidate the comparability and reliability of test systems for the determination of AFP concentrations. METHODS: 25 laboratories using 8 different commercial test systems used liquid BIOREF-AFP control serum in their routine internal quality control over a period of one year. For statistical analysis the results were collected centrally. RESULTS: The statistical analysis of the test results revealed considerable variation for the different laboratories. The deviations of the mean values of different laboratories from the overall mean value varied between 0.1 and 26.1%, and for most of the laboratories the deviation was round about 10%. The precision of measured values in the individual laboratories was in most cases acceptable: Nevertheless, the coefficients of variation of the individual laboratories ranged from 13 to 16.1%. CONCLUSIONS: In conclusion, this study indicates that AFP results vary between different laboratories albeit an international standard for AFP is available. Therefore, every laboratory should participate in external ring studies and should use a quality control serum independent of the test kit manufacturer for the internal quality control.

Comparison and evaluation of Osiris and Sirscan 2000 antimicrobial susceptibility systems in the clinical microbiology laboratory.

The Osiris and Sirscan 2000 systems are two semiautomated systems that can be used to read and interpret the results on disk diffusion agar plates. They are both used for determination of susceptibility to antimicrobial agents. The present study compared both systems versus the NCCLS standard method of visual reading with a ruler. Both inpatient and outpatient samples with a total of 315 nonfastidious gram-negative strains were obtained. In total, 3724 organism-antimicrobial agent combinations that fulfilled the NCCLS guidelines for disk diffusion susceptibility testing were evaluated prospectively. The results obtained with both systems in comparison with those obtained by the classical nonautomated means of interpretation were excellent, with correlation coefficients of 0.96 for both systems. The overall agreements for susceptibility interpretation were 96.56 and 96.24% with the Osiris and Sirscan systems, respectively. Very major errors were obtained for 8 (1.07%) and 10 (1.34%) organism-antimicrobial agent combinations with the Osiris and Sirscan systems, respectively. In addition, major errors were obtained for 2 (0.07%) and 6 (0.21%) combinations with the Osiris and Sirscan systems, respectively. Minor errors were obtained for 118 and 124 organism-antimicrobial agent combinations with the Osiris and Sirscan systems, respectively. Overall, both the Osiris system and the Sirscan system are comparable and reliable systems for determination of interpretative categories from the zone diameters of standard disk diffusion test plates.

Rothia dentocariosa, endocarditis and mycotic aneurysms: case report and review of the literature.

Rothia dentocariosa is a rare cause of endocarditis. It occurs most frequently in patients with prior heart conditions. Although the clinical course is typically subacute, it has a high rate of complications. In particular, the reported incidence of mycotic aneurysms is as high as 25%. Penicillin is the treatment of choice, but additional complications may necessitate prompt surgical intervention. As far as we know, this paper reports the first case of repeated subarachnoid hemorrhages due to R. dentocariosa endocarditis.

Streptococcus pneumoniae-infected aneurysm extending from a persistent lobar pneumonia: case report and review of the literature.

Presented here is the case of a 63-year-old patient with a Streptococcus pneumoniae-infected aneurysm extending from a persistent lobar pneumonia of the left lung into the thoracic aorta. The patient was successfully treated with surgery and high-dose penicillin, and he remained well at 6-month follow-up. A review of the English-language literature over the past 25 years revealed 22 cases of mycotic or infected aortic aneurysms due to Streptococcus pneumoniae; however, none of these cases resulted in a positive outcome for the patient. The characteristics of these cases are discussed.

Natural killer (NK) cell leukaemia in a patient with a B cell non-Hodgkin's lymphoma.

We describe a 74-year-old woman with the diagnosis of natural killer (NK)-cell leukaemia and autoimmune pathology. Four years previously, a diffuse large B cell non-Hodgkin's lymphoma had been diagnosed and treated effectively. Although NK-cell leukaemia has been thought to be a distinct highly aggressive clinicopathological entity, our case shows no further evolution at the present time. As far as we know, this association has not been previously described in the literature.

Peripheral blood T and B lymphocyte subpopulations in infants with acute respiratory syncytial virus brochiolitis.

Most data concerning immunopathogenetic mechanisms involved in respiratory syncytial virus (RSV) infection are derived from animal studies. In infants with RSV bronchiolitis the target organ i.e. the airway is hard to explore. We looked for specific alterations in peripheral blood lymphocyte subpopulations in infants hospitalized for RSV bronchiolitis. Flow cytometric analysis with a large panel of monoclonals was performed on peripheral blood lymphocytes in thirty-two infants (mean age: 4.9 months) admitted for RSV bronchiolitis. Data collected on admission were compared with age-matched control values and also with results obtained at the end of the first week of hospitalization. Differences between age-groups (older or younger than 4 months) and between clinical subgroups (clinical severity score more or less than 6) were looked for. In the group of infants as a whole, regardless of age and clinical score the number of CD4+ cells on admission was significantly elevated compared to normal values for age (p<.0001) including a high fraction of the naive suppressor-inducer subpopulation (CD4+/CD45RA+) and a low fraction of the reciprocal memory helper-inducer subpopulation (CD4+/CD29+). Within the CD8+ cell population the number of T cells with cytotoxic activity (CD8+/S6F1+) was significantly elevated (p<.0001) as were other types of cytotoxic cells. A significant decrease (p<.0001) in the proportion of the precursor/suppressor-effector subpopulation (CD8+/S6F1-) was seen. Absolute numbers and percentages of CD19+ B cells were significantly elevated (p<.0001) with a significant increase in the CD5+ subfraction (p<.0001) as well as in the CD10+ subfraction (p<.0001). In the older age group immunophenotypic cytotoxicity was more pronounced with increased clinical score. During recovery the CD45RA+:CD29+ ratio tended to normalize within the CD4+ T cells. Within the B lymphocyte subsets significant increase in the CD19+/CD5+ fraction (p<.05) was seen. We conclude that there are significant changes in the number of peripheral blood lymphocyte subsets in infants with RSV bronchiolitis as compared to age-related controls. We hope that present data could be useful in further exploration of RSV immunology in humans. A possible link between RSV bronchiolitis and the subsequent development of atopy is mentioned.

Lymphocyte subpopulations in healthy newborn infants: comparison of cord blood values with values five days after birth.

Significant differences (p < 0.0001) were demonstrated in lymphocyte subpopulations both in cord blood and in venous blood samples obtained at day 5 from the same healthy infants. Numbers of T lymphocytes increased, especially CD4+/CD45RA+ cells, whereas numbers of B lymphocytes and natural killer cells decreased without changes in CD8+ and other cytotoxic cells.