Apparent Clinical Significance Research Articles

Are bacteria, fungi, and archaea present in the midtrimester amniotic fluid?

This study was conducted to determine whether bacteria, fungi, or archaea are detected in the amniotic fluid of patients who underwent midtrimester amniocentesis for clinical indications. Amniotic fluid samples from 692 pregnancies were tested by using a combination of culture and end-point polymerase chain reaction (PCR) techniques. Intra-amniotic inflammation was defined as an interleukin-6 concentration >2,935 pg/mL. Microorganisms were detected in 0.3% (2/692) of cases based on cultivation, 1.73% (12/692) based on broad-range end-point PCR, and 2% (14/692) based on the combination of both methods. However, most (13/14) of these cases did not have evidence of intra-amniotic inflammation and delivered at term. Therefore, a positive culture or end-point PCR in most patients appears to have no apparent clinical significance. Amniotic fluid in the midtrimester of pregnancy generally does not contain bacteria, fungi, or archaea. Interpretation of amniotic fluid culture and molecular microbiologic results is aided by the assessment of the inflammatory state of the amniotic cavity. The presence of microorganisms, as determined by culture or a microbial signal in the absence of intra-amniotic inflammation, appears to be a benign condition.

Single-cell computational machine learning approaches to immune-mediated inflammatory disease: New tools uncover novel fibroblast and macrophage interactions driving pathogenesis.

Recent advances in single-cell sequencing technologies call for greater computational scalability and sensitivity to analytically decompose diseased tissues and expose meaningful biological relevance in individual cells with high resolution. And while fibroblasts, one of the most abundant cell types in tissues, were long thought to display relative homogeneity, recent analytical and technical advances in single-cell sequencing have exposed wide variation and sub-phenotypes of fibroblasts of potential and apparent clinical significance to inflammatory diseases. Alongside anticipated improvements in single cell spatial sequencing resolution, new computational biology techniques have formed the technical backbone when exploring fibroblast heterogeneity. More robust models are required, however. This review will summarize the key advancements in computational techniques that are being deployed to categorize fibroblast heterogeneity and their interaction with the myeloid compartments in specific biological and clinical contexts. First, typical machine-learning-aided methods such as dimensionality reduction, clustering, and trajectory inference, have exposed the role of fibroblast subpopulations in inflammatory disease pathologies. Second, these techniques, coupled with single-cell predicted computational methods have raised novel interactomes between fibroblasts and macrophages of potential clinical significance to many immune-mediated inflammatory diseases such as rheumatoid arthritis, ulcerative colitis, lupus, systemic sclerosis, and others. Third, recently developed scalable integrative methods have the potential to map cross-cell-type spatial interactions at the single-cell level while cross-tissue analysis with these models reveals shared biological mechanisms between disease contexts. Finally, these advanced computational omics approaches have the potential to be leveraged toward therapeutic strategies that target fibroblast-macrophage interactions in a wide variety of inflammatory diseases.

A combined approach of rolling-circle amplification-single site restriction endonuclease digestion followed by next generation sequencing to characterize the whole genome and intra-host variants of human Torque teno virus

Torque Teno Virus (TTV) was initially associated with post-transfusion hepatitis, but growing evidence of its ubiquity in humans is compatible to no apparent clinical significance. TTV is a small non-enveloped virus with a circular single-negative-stranded DNA genome, belonging to the Anelloviridae family. Currently, TTVs are divided in seven phylogenetic groups and are further classified into 21 species. Studies about diversity of TTV in different conditions are receiving increasing interest and in this sense, sequencing of whole genomes for better genetic characterization becomes even more important. Since its discovery in 1997, few TTV complete genomes have been reported worldwide. This is probably due, among other reasons, to the great genetic heterogeneity among TTV strains that prevents its amplification and sequencing by conventional PCR and cloning methods. In addition, although metagenomics approach is useful in these cases, it remains a challenging tool for viromic analysis. With the aim of contributing to the expansion of the TTV whole genomes dataset and to study intra-host variants, we employed a methodology that combined a rolling-circle amplification approach followed by EcoRI digestion, generating a DNA fragment of ∼4Kb consistent with TTV genome length which was sequenced by Illumina next generation sequencing. A genogroup 3 full-length consensus TTV genome was obtained and co-infection with other species (at least those with a single EcoRI cleavage site) was not identified. Additionally, bioinformatics analysis allowed to identify the spectrum of TTV intra-host variants which provides evidence of a complex evolution dynamics of these DNA circular viruses, similarly to what occurs with RNA viruses.

Spontaneous Coronary Artery Dissection and Anomalous Coronary Origin – Underlying Cause of Acute Coronary Syndrome in a Young Woman: A Case Report

Abstract Introduction: Spontaneous coronary artery dissection (SCAD) represents a very rare and poorly understood condition that is gaining recognition as an important cause of myocardial infarction, especially among young women. The pathogenesis of SCAD is not well established yet, but several theories have been proposed. Case presentation: We report the case of a 25-year-old woman without any history of cardiovascular disease who presented with acute anterior ST-elevation myocardial infarction (STEMI) due to the luminal obstruction generated by an intramural hematoma from a SCAD of the left main coronary artery, which was successfully treated by coronary artery stenting. Additionally, the patient presented anomalies of coronary origins (ACO) with separate emergences of the left anterior descending (LAD) artery from the left coronary cusp and the left circumflex artery (LCX) from the right coronary cusp, with no apparent clinical significance. Conclusion: SCAD should always be included in the differential diagnosis of young patients presenting with STEMI. In case of prompt diagnosis, SCAD-STEMI patients are successfully treated with percutaneous coronary intervention (PCI). Moreover, it is of vital importance to identify variants of ACO, even without clinical relevance at the moment of the acute event, in order to initiate an appropriate management, since ACO increases the risk of routine PCI.

Constant companion: clinical and developmental aspects of torque teno virus infections.

Torque teno virus (TTV) is a commensal human virus observed as a circular single-negative-strand DNA molecule in various tissues and biological samples, notably in blood serum and lymphocytes. TTV has no apparent clinical significance, although it might be very useful as a prospective tool for gene delivery or as an epidemiological marker. Human populations are ubiquitously infected with TTV; the prevalence may reach 100%. The majority of babies become spontaneously infected with TTV, so that by the end of the first year of life, the prevalence reaches 'adult' values. TTV positivity in healthy early infancy and the presence of TTV in umbilical cord blood samples have been reported. The mechanism of infection and the dynamics of TTV prevalence in infants with age remain understudied. Meanwhile, the potential diagnostic and prognostic value of TTV as a marker deserves special attention and study, along with the possibility, causes and consequences of placental transmission of TTV under normal or pathological conditions.

Arterial lactate does not predict outcome better than existing risk scores in upper gastrointestinal bleeding

Objective: Upper gastrointestinal bleeding (UGIB) is a frequent medical emergency and several scoring systems are developed to help risk-stratify patients. We aimed to investigate if elevated arterial lactate (AL) was associated with 30-day mortality, need for hospital-based intervention, or rebleeding. Furthermore, we compared the performance of AL with existing scoring systems and examined if incorporation of AL could improve their predictive ability.Materials and methods: Retrospective cohort study of 331 consecutive patients admitted with UGIB during a one-year period. Multivariate analyses were performed to evaluate the association between AL and outcomes. Receiver operating characteristic curves were used to compare AL with existing scoring systems and to test if incorporation of AL could significantly increase their performance.Results: AL was significantly associated with mortality (p = .001), need for hospital-based intervention (p = .005), and rebleeding (p = .031). In predicting mortality and rebleeding, AL performed equally to existing scoring systems, however, inferior to all, in predicting need for intervention. Two of the scoring systems were marginally improved in predicting mortality if AL was included.Conclusions: AL is associated with adverse outcomes in patients with UGIB, but has only similar or inferior ability to predict relevant clinical outcomes compared to existing scoring systems. Although AL could enhance performance of two scorings systems in predicting mortality, it does not have an apparent clinical significance. Thus, our data does not support routine measurement of AL in patients with UGIB.

Bioimpedance analysis vs. DEXA as a screening tool for osteosarcopenia in lean, overweight and obese Caucasian postmenopausal females.

We aimed at evaluating the efficiency of a newly developed, advanced Bioimpedance Analysis (BIA-ACC®) device as a screening tool for determining the degree of obesity and osteosarcopenia in postmenopausal women with normal or decreased bone density determined by Dual-Energy X-Ray absorptiometry (DEXA) in a representative sample of Greek postmenopausal women. This is a single-gate cross-sectional study of body composition measured by BIA-ACC® and DEXA. Postmenopausal females with BMI ranging from 18.5 to 40 kg/m2 were subjected to two consecutive measurements of DEXA and BIA-ACC® within 5-10 minutes of each other. We used Pearson's co-efficient to examine linear correlations, the intraclass correlation co-efficient (ICC) to test reliability, Bland-Atman plots to assess bias and Deming regressions to establish the agreement in parameters measured by BIA-ACC® and DEXA. Last, we used ANOVA, with Bonferroni correction and Dunnett T3 post hoc tests, for assessing the differences between quantitative and Pearson's x2 between qualitative variables. Our sample consisted of 84 overweight/obese postmenopausal women, aged 39-83 years, of whom 22 had normal bone density, 38 had osteopenia and 24 had osteoporosis based on DEXA measurements, using quota sampling. ICCs and Deming regressions showed strong agreement between BIA-ACC® and DEXA and demonstrated minimal proportional differences of no apparent clinical significance. Bland-Altman plots indicated minimal biases. Fat, skeletal and bone mass measured by BIA-ACC® and DEXA were increased in the non-osteopenic/non-osteoporotic women compared with those of the osteopenic and osteoporotic groups. BIA-ACC® is a rapid, bloodless and useful screening tool for determining body composition adiposity and presence of osteo-sarcopenic features in postmenopausal women. Women with osteopenia and osteoporosis evaluated by DEXA had decreased fat, skeletal and bone mass compared with normal bone density women, suggesting concordance in the change of these three organ masses in postmenopausal women.

Cyclin D1 expression and polysomy in lymphocyte-predominant cells of nodular lymphocyte-predominant Hodgkin lymphoma.

Cyclin D1 protein expression in lymphocytes is classically associated with mantle cell lymphoma. Although increasingly recognized in other lymphoproliferative disorders, cyclin D1 expression and CCND1 gene abnormalities have not been well studied in nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL). Using a double stain for CD20/cyclin D1, we quantified cyclin D1 expression in 10 cases of NLPHL and correlated those findings with SOX11 expression, CCND1 gene abnormalities, and clinical data. For comparison, we examined 5 cases of T cell-/histiocyte-rich large B-cell lymphoma (THRLBCL). All cases of NLPHL stained for cyclin D1 showed at least rare positivity in lymphocyte-predominant (LP) cells. In 4 cases, at least 20% of LP cells were positive for CD20/cyclin D1. Neither SOX11 expression nor CCND1 gene rearrangement was found in any of the cases, but fluorescence in situ hybridization showed a proportion of the large cells with 3 to 4 copies of nonfused IGH and CCND1 signals or 3 intact CCND1 break-apart signals. Further study with CCND1/CEP11 showed polysomy in 6 of 9 cases with cyclin D1 expression and 5 of 16 NLPHL not examined for cyclin D1. Two of 5 cases of THRLBCL showed rare positive staining for CD20/cyclin D1; 1 case showed polysomy with CCND1/CEP11. Results show that cyclin D1 may be expressed in LP cells without SOX11 expression or CCND1 translocation. Polysomy with increased copies of CCND1 may account for cyclin D1 expression in some cases. Cyclin D1 expression is not useful for distinguishing NLPHL from THRLBCL and has no apparent clinical significance in NLPHL.

Sequence analysis of four vitamin D family genes (VDR, CYP24A1, CYP27B1 and CYP2R1) in Vogt-Koyanagi-Harada (VKH) patients: identification of a potentially pathogenic variant in CYP2R1.

BackgroundVKH is a rare autoimmune disease. Decreased level of vitamin D has recently been found to be involved in the pathogenesis of Vogt-Koyanagi-Harada (VKH) disease. This study was designed to screen the vitamin D pathway genes for pathogenic mutations, if any, in VKH patients.MethodsGenomic DNA was extracted from blood samples collected from patients with VKH disease and healthy controls. Entire coding region, exon-intron junctions of four genes were sequenced in DNA from 39 Saudi VKH patients and 50 ethnically matched healthy individuals. All patients and controls were unrelated.ResultsVitamin D levels in VKH patients were found either insufficient (21–29 ng/mL) or deficient (<20 ng/mL). Sequencing analysis of the VDR, CYP24A1, CYP27B1 and CYP2R1 detected twelve nucleotide changes in these genes in our cohort of 39 patients; 4 of which were non-coding, 6 were synonymous coding and 2 were non-synonymous coding sequence changes. All synonymous coding variants were benign polymorphisms with no apparent clinical significance. A non-synonymous coding sequence variant (c.2 T > C; p.1Met?) found in VDR is an initiation coding change and was detected in control individuals as well, while another variant (c.852G > A; p.284 M > I) found in CYP2R1 is predicted to be disease causing by mutationtaster software. This potentially pathogenic variant was found in 17 out of 39 VKH patients.ConclusionsScreening of four Vitamin D pathway genes in 39 VKH patients shows that a potentially pathogenic sequence variant in CYP2R1 may cause VKH in a subset of patients. These findings support the previous observation that low vitamin D levels might play a role in VKH pathogenesis and mutations in genes involved in vitamin D anabolism and catabolism might be of importance in VKH pathobiology.

Rhythmic electrographic discharges during deep hypothermic circulatory arrest

ObjectiveThe main objective of this study is to examine the prevalence and timing of rhythmic electrographic discharges and periodic sharp transients during aortic arch repair surgeries using DHCA as detected by continuous intraoperative encephalogram (EEG) and correlate it with outcome. MethodsElectronic medical records and the intraoperative EEGs of 32 patients who underwent aortic arch reconstruction with DHCA were reviewed. Preoperative patient characteristics, intraoperative data, and postoperative outcomes were examined. EEGs were graded based on the frequency of sharp transients (grade 0–2) and/or the presence of rhythmic electrographic discharges (grade 3). ResultsPeriodic sharp transients were seen in 30/32 cases. Grade 1 and grade 2 activations were more prominent during cooling at nasopharyngeal temperature of 23.9±4.01°C (mean±SDV). Rhythmic electrographic discharges occurred in seven patients and were exclusively seen during cooling at nasopharyngeal temperatures below 28°C except in one case during rewarming at nasopharyngeal temperatures of 22°C. No patient with rhythmic discharges developed postoperative clinical neurologic deficit or seizures. ConclusionsPeriodic sharp transients occurred in almost all cases during induction of deep hypothermia. This activity was not associated with postoperative neurologic deficit. SignificanceClinical neurophysiologists, technicians and surgeons need to be aware that low amplitude periodic sharp transients and rhythmic electrographic discharges are common during DHCA, yet have no apparent clinical significance.

High prevalence of Tritrichomonas foetus ‘bovine genotype’ in faecal samples from domestic pigs at a farm where bovine trichomonosis has not been reported for over 30 years

Bovine venereal trichomonosis caused by the flagellate Tritrichomonas foetus is a notifiable disease in Australia. While, T. foetus is pathogenic in both cattle and cats, it has long been established that the same T. foetus colonises the stomach, caecum and nasal cavity of pigs without apparent clinical significance. Multi-locus genotyping grouped the non-pathogenic porcine T. foetus with the pathogenic ‘bovine genotype’, rather than with the ‘feline genotype’ T. foetus. Bovine trichomonosis is now uncommon due to wide-spread use of artificial insemination, however, whether T. foetus remains prevalent in pigs where bovine trichomonosis has been eradicated remains unknown. We surveyed faecal samples from pigs farmed in close proximity with T. foetus-negative cattle. The Modified Diamond's Medium assay used were 77.4% (24/31) positive for trichomonads and 64.50% (20/31) were T. foetus-positive based on real-time PCR and conventional PCR. An axenic reference strain of T. foetus, designated PIG30/1 was established. In addition, a novel trichomonad ITS rDNA, PIG12, closely related to sequences from Trichomitus spp is reported. Multi-locus genotyping at nine loci matched PIG30/1 to the ‘bovine genotype’ T. foetus. In conclusion, cross-species transmission of T. foetus between pigs and cows from environmental exposure of T. foetus-contaminated pig faeces is unlikely. Domestic T. foetus-positive pigs possess a negligible risk of a successful T. foetus transmission event to cattle.

FISH is not Suitable as a Standalone Test for Detecting Fetal Chromosomal Abnormalities

AbstractKaryotyping and fluorescence in situ hybridization (FISH) detect fetal chromosome abnormalities. The choice between karyotyping and FISH is still debatable. In a developing country, parents face an emotional and economic constraint of a prenatal test. Therefore, the results of karyotyping and FISH were analyzed to determine the percentage of clinically abnormal fetuses which would be missed by using standalone FISH. Amniotic fluid samples from 9033 high-risk pregnancies were subjected to karyotyping and FISH for chromosomes 13, 18, 21, X, and Y. Karyotype and FISH were normal in 8680 (96.1 %) of these samples and 353 (3.9 %) had abnormal karyotypes: 285 (3.2 %) were aneuploidies, also detected by FISH and 68 (0.7 %) were structural chromosomal aberrations not detected by FISH. Out of these 68 structural aberrations, 40 (0.4 %) were balanced rearrangements with no apparent clinical significance and 28 (0.3 %) were unbalanced rearrangements with potential clinical significance. By standalone FISH, 0.3 % clinically-significant samples would have been missed. A 0.2 % risk of procedure-related abortion may be acceptable but a 0.3 % risk of having an abnormal child may not be acceptable to the parents. FISH may be offered as a first test, followed by karyotyping. Although, karyotyping increases the cost, it is preferable to carry this out once an invasive procedure has been opted for, with its accompanying risk of miscarriage.

Prospective Study of QTc Changes Among Former Opiate Addicts Since Admission to Methadone Maintenance Treatment

To prospectively evaluate QTc changes among methadone maintenance treatment (MMT) patients. All 512 opiate addicts newly admitted to 2 MMT clinics had been prospectively studied for 4.5 years. Ninety-one patients were excluded because they were admitted from other MMTs, and 26 were excluded because their first electrocardiogram was performed following 28 days in MMT; therefore, 421 were studied. QTc values were again performed either after (A) a steady methadone dose for at least 3 months and negative urine tests for opiates, cocaine, amphetamines, cannabis, benzodiazepine; or after (B) same as for (A) but with positive urine tests for cannabis and/or benzodiazepine. Mean QTc intervals were not related to benzodiazepine or cocaine use on admission. QTc interval was significantly prolonged from the baseline to steady methadone dose (424.5 ± 23.2 ms and 438.6 ± 26.6 ms, respectively) but not affected by methadone dose (<100 or ≥100 mg/d) or by the time to achieve a steady methadone dose (between 3 months and >2 years). QTc prolongation was greater among patients whose urine tested positive for benzodiazepine on a steady dose (P = 0.003). No additional prolongation was observed in 49 patients who achieved a steady methadone dose less than 1 year in MMT and had additional follow-up. Two patients who were benzodiazepine abusers died for undefined reasons. There is significant QTc prolongation during early MMT with no apparent clinical significance. A combination of benzodiazepine and methadone should be monitored.

Isolated GH Deficiency due to a GHRH Receptor Mutation Causes Hip Joint Problems and Genu Valgum, and Reduces Size but not Density of Trabecular and Mixed Bone

The GH/IGF-I axis is important for bone growth, but its effects on joint function are not completely understood. Adult-onset GH-deficient individuals have often reduced bone mineral density (BMD). However, there are limited data on BMD in adult patients with untreated congenital isolated GH-deficient (IGHD). We have shown that adult IGHD individuals from the Itabaianinha, homozygous for the c.57+1G>A GHRHR mutation, have reduced bone stiffness, but BMD and joint status in this cohort are unknown. The goal is to study BMD, joint function, and osteoarthritis score in previously untreated IGHD adults harboring the c.57+1G>A GHRHR mutation. This is a cross-sectional study. Areal BMD by dual-energy X-ray absorptiometry was measured in 25 IGHD and 23 controls (CO). Volumetric BMD (vBMD) was calculated at the lumbar spine and total hip. Joint function was assessed by goniometry of elbow, hips, and knees. X-rays were used to measure the anatomic axis of knee and the severity of osteoarthritis, using a classification for osteophytes (OP) and joint space narrowing (JSN). Genu valgum was more prevalent in IGHD than CO. The osteoarthritis knees OP score was similar in both groups, and knees JSN score showed a trend to be higher in IGHD. The hips OP score and JSN score were higher in IGHD. Areal BMD was lower in IGHD than CO, but vBMD was similar in the two groups. Range of motion was similar in elbow, knee, and hip in IGHD and CO. Untreated congenital IGHD due to a GHRHR mutation causes hip joint problems and genu valgum, without apparent clinical significance, reduces bone size, but does not reduce vBMD of the lumbar spine and hip.

An exploratory investigation of purging disorder

ObjectivePurging Disorder (PD) is an understudied pattern of behaviors within the Eating Disorder Not Otherwise Specified (EDNOS) category. Such categorization may suggest that PD is not clinically significant as other eating disorders. However, evidence has suggested that PD is associated with significant impairments in psychosocial functioning and well-being. Despite the apparent clinical significance of PD, it remains to be determined if PD is distinct from other clinically significant eating disorders. The present study sought to assess the phenomenology, clinical significance, and distinctiveness of PD. MethodGroup scores on measures of eating pathology, body image disturbance, and psychological correlates were compared using MANOVA among a female undergraduate sample (N=94) meeting diagnostic criteria for PD (n=20), Bulimia Nervosa (BN; n=35), restrained eating (n=18), and healthy controls (n=21). ResultsOverall, results indicated the PD group reported less severe symptoms than BN but more severe symptoms than controls. The PD and restraint groups were similar on most variables (including subjective binge behavior), with the exception of perfectionism and hunger. DiscussionFindings support the conceptualization of PD as existing along a spectrum of bulimic spectrum disorders rather than as a distinct diagnostic category.

Abnormal elevation of erythrocyte mean corpuscular volume (MCV) in non-small cell lung cancer (NSCLC) patients treated with maintenance pemetrexed-based chemotherapy.

e17564 Background: Pemetrexed (Pem) is commonly used as frontline +/- maintenance chemotherapy (MCTx) in patients (pts) with advanced non-squamous (ns) NSCLC. Due to Pem toxicity profile, pts can remain on therapy (tx) for prolonged periods of time. We are reporting an increase in the erythrocyte MCV without apparent clinical significance. Methods: 54 ns-NSCLC pts previously treated with Pem-based tx either as initial treatment followed by MCTx Pem alone or Pem/bevacizumab (Bev) or second line tx were analyzed for elevation of MCV from a normal baseline (80-98 fl). All pts were on daily folic acid (FA) and vitamin B12 (vitB12) supplementation at least every 3 cycles of Pem. Co-factors such as FA, vitB12, homocysteine (Hom), and methylmalonic acid (MMA) were measured on those pts still alive, on active MCTx, and available who had high MCV. Results: 54 pts were evaluable; 50 pts received platinum/Pem/Bev triplet as initial tx followed by Pem/Bev or Pem MCTx and 2 pts with Pem/Bev and Pem alone as second line, respectively. Median age: 63 yrs old (34-84); 32 pts were male and 31 pts (56%) Hispanic. 32 pts (58%) developed an elevated MCV (range: 98.1-114). For the entire cohort, median # cycles of Pem given 11 (range: 2-38). In those pts who had high MCV, the median # of Pem cycles given was 12 (range: 5-38). All pts had normal or low MCV prior to tx, but one. Unfortunately, 33 pts had progressed and are no longer on MCTx. 12 pts out of the 19 still on MCTx had high MCV. In 5/12 pts, we were able to measure their co-factor levels. All values were within normal limits. The MCVs of these 5 pts were: 101.6, 100, 102.1, 102.2, and 104.8 from baseline values of: 74.4, 89.3, 92.8, 89.7, and 89.6, respectively. Their Hbg levels were: 12.2, 13.2, 15.4, 11.4, and 11 g/dL, respectively with normal WBC (and differential) and platelets. Conclusions: Pem is an antifolate agent that is associated with folate depletion (due to TS inhibition) and macrocytosis. We are reporting here patients treated with Pem for long time with proper FA and vitB12 supplementation that have an increased MCV with no apparent signs of folate, vitB12, MMA, and Hom deficiency. This observation needs a lengthened follow-up.

Practice Guidelines for the Interpretation and Reporting of Transient Therapy-Related Single Metaphase Chromosomal Abnormalities Identified by Routine Metaphase Cytogenetics in Bone Marrow Specimens,

Abstract 4208 Introduction: Metaphase cytogenetic (MG) studies are routinely performed on bone marrow aspirate specimens in patients with hematologic disorders. While more sensitive tests are available which target specific aberrations, MG remains an inexpensive method to identify both anticipated and unanticipated global changes. However, due to the occasional finding of non-clonal changes in single metaphases, the International System for Human Cytogenetic Nomenclature recommends that the abnormality be present in at least two cells (three cells for losses of whole chromosomes) before it is considered a clonal change. Noting a high frequency of single metaphase chromosomal abnormalities (SMCAs) in the heavily pre-treated population at Vanderbilt University Medical Center (VUMC), we sought to quantify the incidence of those SMCAs with minimal or no apparent clinical significance and to determine the best interpretation and reporting mechanism for such changes. Methods: Retrospective data was collected and analyzed from a 16 month period encompassing March 2010 to June 2011. During this time period, all cases of SMCAs were identified. For each instance all tandem ancillary studies (fluorescent in situ hybridization (FISH), molecular studies) as well as all prior and subsequent cytogenetic studies associated with bone marrow biopsies were analyzed. Results: A total of 2916 bone marrow biopsies were performed at VUMC during this 16 month time frame. Of these 2916 cases, 680 had abnormal karyotypes, including 151 instances of chromosomal aberrations which were identified in only a single cell out of at least twenty metaphases examined (SMCAs). These 151 instances corresponded to 133 patients. Compared to the overall distribution of bone marrow diagnoses/indications at VUMC, there were a disproportionately high number of cases of acute myeloid leukemia (AML)and/or myelodysplasia (MDS) (45% of SMCAs versus 31% of total VUMC bone marrow biopsies) and lymphoma (15% of SMCAs versus 5%) (chi-square test, p-value &lt; 0.001). Across diagnoses, 79% of all cases were found in patients after chemotherapy or radiation treatment, with a very high association with prior therapy in cases of AML (94%), B lymphoblastic leukemia (100%), myeloproliferative neoplasms (100%), lymphoma (85%), and MDS (84%). Only cases for which the clinical indication was to rule out bone marrow failure had a significant percentage of SMCAs in untreated marrows, potentially representing stress hematopoiesis. Of the 151 cases of SMCA, 81 (60%) had a prior marrow, a subsequent marrow, or both which did not show the SMCA, suggesting a transient incidental finding of probable minimal clinical significance. An additional 29/151 (19%) cases were seen only once at VUMC, but the aberration had no known clear disease association and are likely of minimal clinical significance. The SMCA was likely indicative of minimal residual disease in only 13 cases (9%), confirmed by concordance with prior marrow findings or tandem FISH studies with known disease association. Only 4 of the 151 cases (2.6% of cases) were of unclear clinical significance at the time of the result but were later confirmed to be significant by identification of a similar finding in a subsequent marrow. Of the SMCAs believed to be transitory and therapy-related, the aberrations clustered with variable changes seen in chromosomes 1 (particularly t(1;19) and t(1;7)), 6, 7, 9, and 13 as well as frequent trisomies of chromosomes 18, 21, and 22. Conclusions: Retrospective analysis identified that 79% of SMCAs identified were of minimal or no clinical significance. Those cases in which the SMCA likely represents a true marker of disease represented only 9% of cases and were readily identifiable at the time of the marrow by correlation with prior cytogenetic findings or tandem FISH. In only 2.6% of cases was an SMCA only subsequently proven to be clinically significant. There was a high association with prior chemotherapy in these SMCA cases, and the cases have preferred “hotspots” of the therapy-related transient chromosomal changes, including numerous translocations. We therefore recommend the de-emphasis of SMCAs in post-therapy specimens by reporting a normal karyotype in the formal interpretation with only mention of the SMCA in a comment to enable correlation with future studies. This reporting scheme will help distinguish true clonal evolution from a transient laboratory finding. Disclosures: No relevant conflicts of interest to declare.

A practical assessment of the short-term in vitro stability of troponin I at the 99th percentile

Serial troponin measurement is important for the diagnosis of myocardial infarction. As troponin concentrations approach the cut-off for detectable myocardial necrosis, smaller changes in troponin as a result of decreased in vitro stability may be sufficient to generate changes of apparent clinical significance. This is particularly relevant regarding retrospective 'add-on' testing on samples several hours after venepuncture. We investigated the stability of troponin I (cTnI) at values close to the 99th percentile limit. Serum samples with baseline cTnI concentrations in the range 0.04-0.15 μg/L were analysed routinely using the Siemens TnI-Ultra assay. Follow-up analysis was carried out at 6, 9, 12, 24 and 48 h post-venepuncture after storage at room temperature and in the cold room. There was a significant decrease in cTnI concentration after 6 h post-venepuncture compared with baseline levels (P < 0.001). The maximum percentage change was -17.1% observed after 48 h storage at room temperature. Of samples with baseline cTnI concentration 0.040 μg/L, 80% had a cTnI concentration below 0.040 μg/L on re-analysis after 6 h. Requests for retrospective addition of troponin measurement on samples several hours after venepuncture is commonplace in many laboratories. Analysis of samples drawn >6 h previously may produce values below the cut-off for myocardial necrosis (0.040 μg/L) that would have been detectable if measured earlier as a result of decreased in vitro stability. Significant percentage decreases in cTnI concentration following storage may also have implications in lowering the threshold for an apparently clinically significant change to occur.

Mycoplasmas and Human prostate cancer: An exciting but cautionary note

A recent study of Barykova, et al. [1] described a significant association between Mycoplasma hominis infection and development of prostate cancer. In the study, the authors detected the presence of M. hominis-specific DNA sequences in examining 496 prostate biopsies by PCR obtained from 248 Russian men undergoing cancer diagnosis. The association appeared to be particularly significant in the statistical analysis between M. hominis infection and development of the higher grade prostate cancer. A possible role for mycoplasmas in association with human malignancy was first noted during 1960s. Several studies reported isolation of mycoplasmas from human leukemic bone marrow [2-6]. A majority of the mycoplasmas isolated in the studies were identified as Mycoplasma fermentans. However, the mycoplasmaoncogenesis hypothesis failed to advance because the same mycoplasmas later could also be found in nonleukemic children or adults, although the mycoplasmas appeared to be most frequently isolated from patients with leukemia [7]. Koch’s postulate of identifying the causative agent in an infectious disease by finding a specific pathogen uniquely present in a particular disease process overshadowed the characteristics in both chronicity and multi-factorial nature of the malignant process. Mycoplasmas are a heterogeneous group of very small organisms capable of self-replication. The wallfree microbes can cause a wide variety of diseases in animals. Some mycoplasmas cause respiratory or urogenital diseases in humans. However, many other mycoplasmas chronically colonize our respiratory and urogenital tracts without apparent clinical significance [8]. Various mechanisms including “antigenic variation” may be critical in the ability of these microbial species to evade host antibody responses or other elements of

C1q deposition in the renal allograft: a report of 24 cases

C1q nephropathy is an uncommon glomerular disease characterized by dominant or codominant mesangial staining for C1q in the absence of systemic lupus erythematosus. There are no series in the literature addressing the significance of C1q deposition in the renal allograft. We retrospectively analyzed 24 patients, most of whom were white (83%) and male (63%), with a mean age at transplant of 31 years. None of the patients were diagnosed with C1q nephropathy in the native kidney or had any features of systemic lupus erythematosus. The mean time from transplant to detection of mesangial C1q deposits was 37 months (>12 months in 71% of cases). Half of the patients had a preceding infection. The indication for biopsy was surveillance (63%) or graft dysfunction (37%). At biopsy, 52% had proteinuria (>1g/day in only 17%). The mean creatinine was 1.8 mg per 100 ml. Only 9% developed hematuria and none had hypoalbuminemia. The glomerular pattern on light microscopy was mesangial hypercellularity (46%), focal segmental glomerulosclerosis (21%), or no lesions (33%). All cases showed intense (≥2+) dominant (67%) or codominant (33%) mesangial staining for C1q on immunofluorescence. Mesangial electron-dense deposits were seen in 82% of cases. On follow-up (mean 1 year) of the 10 patients without rejection, most had stable creatinine with no or stable proteinuria, and none lost their graft. We conclude that C1q-dominant mesangial deposition in the renal allograft is a morphological pattern with no apparent clinical significance in the majority of patients. It is usually detected after the first year. The rate of preceding infection and the prevalence of proteinuria seem to be similar to the renal transplant recipients in general. Most cases show mesangial hypercellularity or no glomerular changes on light microscopy.