Third reported patient with RAP1B-related syndromic thrombocytopenia and novel clinical findings.

RAP1B is a RAS-superfamily small GTP-binding protein involved in numerous cell processes. Pathogenic gain-of-function variants in this gene have been associated with RAP1B-related syndromic thrombocytopenia, an ultrarare disorder characterized by hematologic abnormalities, neurodevelopmental delays, growth delay, and congenital birth defects including cardiovascular, genitourinary, neurologic, and skeletal systems. We report a 23-year-old male with a novel, de novo RAP1B gain-of-function variant identified on genome sequencing. This is the third reported case which expands the molecular and phenotypic spectrum of RAP1B-related syndromic thrombocytopenia.

Quantitative Pupillometry in the Intensive Care Unit.

Quantitative pupillometry provides a noninvasive and objective assessment within the neurological examination. This review details the physiology of the pupillary light response, the clinical significance of changes in pupillary reactivity, and the variables that compose the Neurological Pupil index or NPi are discussed. This article reviews the most recent applications and advances in quantitative pupillometry for noninvasive intracranial pressure monitoring, postcardiac arrest prognostication, and subarachnoid hemorrhage. Also discussed are the limitations and confounders of quantitative pupillometry in the modern neurological intensive care unit.

Early Initiation of Oral Antihypertensives Reduces Intensive Care Unit Stay and Hospital Cost for Patients with Hypertensive Intracerebral Hemorrhage.

BACKGROUND/OBJECTIVE: Intravenous nicardipine infusion is effective for rapid blood pressure control. However, its use requires hemodynamic monitoring in the intensive care unit (ICU) and is associated with high hospital cost. This study aimed to examine the effect of early versus late initiation of oral antihypertensives on ICU length of stay (LOS) and cost of hospitalization in patients with hypertensive intracerebral hemorrhage (ICH). METHODS: This is a single-center retrospective study of patients with hypertensive ICH treated with nicardipine infusion from January 1, 2013, to December 31, 2017. Patients were dichotomized into study and control groups, based on receiving oral antihypertensives within 24 h versus after 24 h of emergency department arrival. Baseline characteristics, duration of nicardipine infusion, LOS in the ICU and hospital, functional outcome at discharge, and hospital cost were compared between the two groups using univariate and multivariate analysis. RESULTS: A total of 90 patients in the study group and 76 in the control group were identified. There was no significant difference in demographics, past medical history, and initial SBP between the two groups. After adjusting for confounding factors with multivariate regression models, early initiation of oral antihypertensives was associated with significant reductions in duration of nicardipine infusion (55.5 ± 60.1 vs 121.6 ± 141.3 h, p <0.005), nicardipine cost ($14,207 vs $29,299, p < 0.01), ICU LOS (2 vs 5 days, p < 0.005), and cost of hospitalization ($24,564 vs $47,366, p < 0.01). There was no significant difference in adversary renal events, favorable outcomes, and mortality between the two groups. CONCLUSIONS: Early initiation of oral antihypertensives is safe and may have a significant financial impact on patients with hypertensive ICH.

Biallelic mutations in the ferredoxin reductase gene cause novel mitochondriopathy with optic atrophy.

Iron-sulfur (Fe-S) clusters are ubiquitous cofactors essential to various cellular processes, including mitochondrial respiration, DNA repair, and iron homeostasis. A steadily increasing number of disorders are being associated with disrupted biogenesis of Fe-S clusters. Here, we conducted whole-exome sequencing of patients with optic atrophy and other neurological signs of mitochondriopathy and identified 17 individuals from 13 unrelated families with recessive mutations in FDXR, encoding the mitochondrial membrane-associated flavoprotein ferrodoxin reductase required for electron transport from NADPH to cytochrome P450. In vitro enzymatic assays in patient fibroblast cells showed deficient ferredoxin NADP reductase activity and mitochondrial dysfunction evidenced by low oxygen consumption rates (OCRs), complex activities, ATP production and increased reactive oxygen species (ROS). Such defects were rescued by overexpression of wild-type FDXR. Moreover, we found that mice carrying a spontaneous mutation allelic to the most common mutation found in patients displayed progressive gait abnormalities and vision loss, in addition to biochemical defects consistent with the major clinical features of the disease. Taken together, these data provide the first demonstration that germline, hypomorphic mutations in FDXR cause a novel mitochondriopathy and optic atrophy in humans.

Mosaicism of the UDP-Galactose transporter SLC35A2 in a female causing a congenital disorder of glycosylation: a case report.

BACKGROUND: Congenital disorders of glycosylation are rare conditions caused by genetic defects in glycan synthesis, processing or transport. Most congenital disorders of glycosylation involve defects in the formation or transfer of the lipid-linked oligosaccharide precursor of N-linked glycans. SLC35A2-CDG (previously CDG-IIm) is caused by hemizygous or heterozygous mutations in the X-linked gene SLC35A2 that encodes a UDP-galactose transporter. To date there have only been 10 reported patients with SLC35A2 mutations. Importantly, the patient presented here was not identified in infancy by transferrin isoform analysis, the most common testing to identify patients with a congenital disorder of glycosylation. CASE PRESENTATION: A 27 month old girl with developmental delay, central hypotonia, cerebral atrophy, and failure to thrive with growth retardation was identified by whole exome sequencing to have a mosaic missense variant in SLC35A2 (c.991G > A). This particular variant has been previously reported in a male as a mutation. Comparison of all clinical findings and new information on growth pattern, growth hormone testing and neurodevelopmental evaluation are detailed on the patient presented. CONCLUSION: This patient report increases the clinical and scientific knowledge of SLC35A2-CDG, a rare condition. New information on reduced growth, growth hormone sufficiency, lack of seizures, and neurodevelopmental status are presented. This new information will be helpful to clinicians caring for individuals with SLC35A2-CDG. This report also alerts clinicians that transferrin isoform measurements do not identify all patients with congenital disorders of glycosylation.

Ethical and Professional Challenges Encountered by Laboratory Genetic Counselors.

Laboratory-based genetic counseling is a growing and yet under researched specialty. In this study, 111 laboratory-based genetic counselors employed in various settings (commercial, academic, etc.) completed an online survey assessing demographics and frequency of encountering 16 domains of ethical and professional challenges encountered by clinical genetic counselors defined previously by McCarthy Veach et al. and validated by Bower et al. Forty-nine of the laboratory genetic counselors also provided anecdotes of particularly challenging situations and strategies for their resolution. Most respondents had less than 5 years' experience as laboratory counselors (71 %), worked full-time (75 %) in industry-based laboratories (91 %) with a focus on molecular diagnostics (84 %), and had limited patient contact (91 %). Similar to clinical counselors, every ethical and professional challenge was endorsed as occurring frequently by some respondents. The most common frequently occurring domains for the sample were: facing uncertainty, time and financial resource allocation, attaining and maintaining proficiency, and informed consent. Content analysis of respondents' anecdotes yielded themes that most commonly concerned: professional identity issues, value conflicts, confidentiality, and colleague error. One unique domain labeled professional communication (educating professionals with limited genetics knowledge), and three salient categories within the professional identity domain--gatekeeping, conflicts of interest, and professional image--were extracted from the anecdotes. The most prevalent strategy for resolving challenging situations was inform health care professional. Results suggest laboratory-based genetic counselors generally face similar ethical and professional challenges as clinical genetic counselors but their exact nature and relative frequency differ. These findings contribute to a greater understanding of common and unique experiences of genetic counselors in different professional specialties.

DNA variations in oculocutaneous albinism: an updated mutation list and current outstanding issues in molecular diagnostics.

Oculocutaneous albinism (OCA) is a rare genetic disorder of melanin synthesis that results in hypopigmented hair, skin, and eyes. There are four types of OCA caused by mutations in TYR (OCA-1), OCA2 (OCA-2), TYRP1 (OCA-3), or SLC45A2 (OCA-4). Here we report 22 novel mutations in the OCA genes; 14 from a cohort of 61 patients seen as part of the NIH OCA Natural History Study and eight from a prior study at the University of Minnesota. We also include a comprehensive list of almost 600 previously reported OCA mutations along with ethnicity information, carrier frequencies, and in silico pathogenicity predictions as a supplement. In addition to discussing the clinical and molecular features of OCA, we address the cases of apparent missing heritability. In our cohort, 26% of patients did not have two mutations in a single OCA gene. We demonstrate the utility of multiple detection methods to reveal mutations missed by Sanger sequencing. Finally, we review the TYR p.R402Q temperature-sensitive variant and confirm its association with cases of albinism with only one identifiable TYR mutation.

Mutations in SLC20A2 are a major cause of familial idiopathic basal ganglia calcification.

Familial idiopathic basal ganglia calcification (IBGC) or Fahr's disease is a rare neurodegenerative disorder characterized by calcium deposits in the basal ganglia and other brain regions, which is associated with neuropsychiatric and motor symptoms. Familial IBGC is genetically heterogeneous and typically transmitted in an autosomal dominant fashion. We performed a mutational analysis of SLC20A2, the first gene found to cause IBGC, to assess its genetic contribution to familial IBGC. We recruited 218 subjects from 29 IBGC-affected families of varied ancestry and collected medical history, neurological exam, and head CT scans to characterize each patient's disease status. We screened our patient cohort for mutations in SLC20A2. Twelve novel (nonsense, deletions, missense, and splice site) potentially pathogenic variants, one synonymous variant, and one previously reported mutation were identified in 13 families. Variants predicted to be deleterious cosegregated with disease in five families. Three families showed nonsegregation with clinical disease of such variants, but retrospective review of clinical and neuroimaging data strongly suggested previous misclassification. Overall, mutations in SLC20A2 account for as many as 41% of our familial IBGC cases. Our screen in a large series expands the catalog of SLC20A2 mutations identified to date and demonstrates that mutations in SLC20A2 are a major cause of familial IBGC. Non-perfect segregation patterns of predicted deleterious variants highlight the challenges of phenotypic assessment in this condition with highly variable clinical presentation.

Prenatal chromosomal microarray analysis: a survey of prenatal genetic counselors' experiences and attitudes.

OBJECTIVE: Studies showing the efficacy and accuracy of chromosomal microarray analysis (CMA) in prenatal diagnosis may position it as a first-tier prenatal test. This study seeks to characterize the practices and attitudes of North American prenatal genetic counselors regarding CMA. METHOD: Genetic counselors (N = 196) in Canada and the USA responded to an anonymous online survey. Completed surveys were analyzed (n = 160). RESULTS: Most respondents viewed CMA as useful (73%), presented CMA to patients (84%), and had ordered CMA at least once (69%). The use of full versus targeted arrays varied. Logistic regression analyses identified three significant predictors for the view that prenatal CMA is useful: more prenatal counseling experience, younger age, and previously presenting CMA to a patient. Three factors predicted the likelihood of offering CMA to prenatal patients: percentage of time spent in prenatal practice, belief that CMA is useful, and practicing in the USA (versus Canada). Reasons cited for not using CMA included financial concerns, the possibility of ambiguous results, and ethical concerns. Most respondents (n = 111) believed that ambiguous results are an ethical issue. CONCLUSION: Clinical guidelines for prenatal CMA, further research on specific copy number variants, and broader availability of targeted arrays to reduce ambiguous results are needed.

Update of PAX2 mutations in renal coloboma syndrome and establishment of a locus-specific database.

Renal coloboma syndrome, also known as papillorenal syndrome is an autosomal-dominant disorder characterized by ocular and renal malformations. Mutations in the paired-box gene, PAX2, have been identified in approximately half of individuals with classic findings of renal hypoplasia/dysplasia and abnormalities of the optic nerve. Prior to 2011, there was no actively maintained locus-specific database (LSDB) cataloguing the extent of genetic variation in the PAX2 gene and phenotypic variation in individuals with renal coloboma syndrome. Review of published cases and the collective diagnostic experience of three laboratories in the United States, France, and New Zealand identified 55 unique mutations in 173 individuals from 86 families. The three clinical laboratories participating in this collaboration contributed 28 novel variations in 68 individuals in 33 families, which represent a 50% increase in the number of variations, patients, and families published in the medical literature. An LSDB was created using the Leiden Open Variation Database platform: www.lovd.nl/PAX2. The most common findings reported in this series were abnormal renal structure or function (92% of individuals), ophthalmological abnormalities (77% of individuals), and hearing loss (7% of individuals). Additional clinical findings and genetic counseling implications are discussed.

Impact of post-operative complications on quality of life after pancreatectomy.

CONTEXT: Pancreatectomies for malignant and benign diseases are increasingly being performed worldwide. Recent studies, that have evaluated quality of life in pancreatectomy, have reported conflicting outcomes. OBJECTIVE: This study was undertaken to analyze the quality of life changes reported by patients with pancreatic cancer undergoing pancreatectomy. DESIGN: Post-hoc analysis was performed of a clinical trial examining the safety of intraoperative autotransfusion during oncologic resections. MAIN OUTCOME MEASURES: Perioperative (90-day) complications were graded prospectively using a validated 5-point scale. Quality of life parameters were recorded prospectively by a single trained interviewer preoperatively, at the first post-operative outpatient visit, and at 6 weeks, 3 months, and 6 months follow-up using the EORTC QLQ-C30 and FACT-An instruments. RESULTS: Pancreatectomy for adenocarcinoma was performed in 34 patients with a median follow-up of 2 years (range: 1-1.5 years). Major (grade≥3) complications occurred in 12 (35.3%) of patients. Early (<6 month) recurrence was noted in 2 patients (5.9%). Increased severity of fatigue, pain, dyspnea, and loss of appetite over baseline were noted at initial follow-up (P<0.05); however, symptom scores normalized at 6-week follow-up, and remained stable at 6 months. No significant difference was noted in quality of life metrics between patients with or without major complications (P>0.11). A significant (P=0.023) decline in cognitive function vs. baseline was noted at 6-month follow-up after pancreatectomy. Using a repeated-measures generalized linear model, neither age, nor complication occurrence, nor adjuvant therapy, nor early recurrence accounted for this cognitive decline (P>0.10). CONCLUSION: Quality of life metrics tend to normalize to preoperative levels after pancreatectomy at 6 weeks post-operatively. The occurrence of major complications does not predict a decreased quality of life. The decrease in self-reported cognitive function at six months in this cohort merits further study.

Differences between bipolar compression and ultrasonic devices for parenchymal transection during laparoscopic liver resection.

OBJECTIVES: In laparoscopic liver resection, multiple options for parenchymal transection techniques exist; however, none have emerged as superior. The aim of this study was to compare operative characteristics and outcomes between bipolar compression and ultrasonic devices used for parenchymal transection during laparoscopic liver resection. METHODS: A review of a prospective hepatopancreatobiliary database from December 2002 to August 2009 identified 54 patients who underwent laparoscopic liver resection with parenchymal division using either a bipolar compression (n= 35) or an ultrasonic (n= 19) device. Operative data, histology and 90-day complication rates were compared between the groups using analysis of variance (anova) and Pearson's chi-squared test. RESULTS: The two groups did not differ significantly in terms of age, body mass index, parenchymal steatosis/inflammation or number of segments resected. A shorter time of parenchymal transection was noted for the bipolar compression device (median: 35 min; range: 20-65 min) vs. the ultrasonic device (median: 55 min; range: 29-75 min) (P < 0.001). Median total operative time was also shorter using the bipolar compression device (130 min) than the ultrasonic device (180 min) (P= 0.050). No significant differences between device groups were noted for estimated blood loss, complications of any type or liver-specific complications. CONCLUSIONS: Bipolar compression devices may offer advantages over ultrasonic devices in terms of decreased transection time and total operative time. No differences in postoperative complications in laparoscopic liver resection emerged between patients operated using the devices.

Comparative Studies of Cerebral Reperfusion Injury in the Posterior and Anterior Circulations After Mechanical Thrombectomy.

Cerebral reperfusion injury is the major complication of mechanical thrombectomy (MT) for acute ischemic stroke (AIS). Contrast extravasation (CE) and intracranial hemorrhage (ICH) are the key radiographical features of cerebral reperfusion injury. The aim of this study was to investigate CE and ICH after MT in the anterior and posterior circulation, and their effect on functional outcome. This is a retrospective study of all consecutive patients who were treated with MT for AIS at University of California Irvine Medical Center between January 1, 2014, and December 31, 2017. Patient characteristics, clinical features, procedural variables, contrast extravasation, ICH, and outcomes after MT were analyzed. A total of 131 patients with anterior circulation (AC) stroke and 25 patients with posterior circulation (PC) stroke underwent MT during the study period. There was no statistically significant difference in admission NIHSS score, blood pressure, rate of receiving intravenous tPA, procedural variables, contrast extravasation, and symptomatic ICH between the 2 groups. Patients with PC stroke had a similar rate of favorable outcome (mRS 0-2) but significantly higher mortality (40.0% vs. 10.7%, p < 0.01) than patients with AC stroke. Multivariate regression analysis identified initial NIHSS score (OR 1.1, CI 1.0-1.2, p = 0.01), number of passes with stent retriever (OR 2.1, CI 1.3-3.6, p < 0.01), and PC stroke (OR 9.3, CI 2.5-35.1, p < 0.01) as independent risk factors for death. There was no significant difference in functional outcomes between patients with and without evidence of cerebral reperfusion injury after MT. We demonstrated that AC and PC stroke had similar rates of cerebral reperfusion injury and favorable outcome after MT. Cerebral reperfusion injury is not a significant independent risk factor for poor functional outcome.

Novel LMNA mutations in patients with Emery-Dreifuss muscular dystrophy and functional characterization of four LMNA mutations.

Mutations in LMNA cause a variety of diseases affecting striated muscle including autosomal Emery-Dreifuss muscular dystrophy (EDMD), LMNA-associated congenital muscular dystrophy (L-CMD), and limb-girdle muscular dystrophy type 1B (LGMD1B). Here, we describe novel and recurrent LMNA mutations identified in 50 patients from the United States and Canada, which is the first report of the distribution of LMNA mutations from a large cohort outside Europe. This augments the number of LMNA mutations known to cause EDMD by 16.5%, equating to an increase of 5.9% in the total known LMNA mutations. Eight patients presented with either p.R249W/Q or p.E358K mutations and an early onset EDMD phenotype: two mutations recently associated with L-CMD. Importantly, 15 mutations are novel and include eight missense mutations (p.R189P, p.F206L, p.S268P, p.S295P, p.E361K, p.G449D, p.L454P, and p.W467R), three splice site mutations (c.IVS4 + 1G>A, c.IVS6 - 2A>G, and c.IVS8 + 1G>A), one duplication/in frame insertion (p.R190dup), one deletion (p.Q355del), and two silent mutations (p.R119R and p.K270K). Analysis of 4 of our lamin A mutations showed that some caused nuclear deformations and lamin B redistribution in a mutation specific manner. Together, this study significantly augments the number of EDMD patients on the database and describes 15 novel mutations that underlie EDMD, which will contribute to establishing genotype-phenotype correlations.

Novel and recurrent EMD mutations in patients with Emery-Dreifuss muscular dystrophy, identify exon 2 as a mutation hot spot.

Emery-Dreifuss muscular dystrophy (EDMD) is a neuromuscular disorder exhibiting a cardiomyopathy with cardiac conduction defects. X-linked EDMD arises from mutations in the EMD gene, which encodes for a nuclear membrane protein termed emerin. In this study, we describe novel and recurrent EMD mutations identified in 18 probands and three carriers from a cohort of 255 North American patients referred for EDMD genetic mutation analysis. Eight of these mutations are novel including six frameshift mutations (p.D9GfsX24, p.F39SfsX17, p.R45KfsX16, p.F190YfsX19, p.R203PfsX34 and p.R204PfsX7) and two non-sense mutations (p.S143X, p.W200X). Our data augment the number of EMD mutations by 13.8%, equating to an increase of 5.2% in the total known EMD mutations and to an increase of 6.0% in the number of different mutations. Analysis of the exon distribution of mutations within the EMD gene, suggests a nonrandom distribution, with exon 2 as a hot spot. This phenomenon may be due to its high GC content, which at 60% is the most GC-rich exon in the EMD gene.

Phase II comparison study of intraoperative autotransfusion for major oncologic procedures.

BACKGROUND: Intraoperative autotransfusion (IOAT) has been avoided in oncologic surgery because of possible tumor cell dissemination. Through a prior Phase I study, we demonstrated that malignant cells are not present in blood filtered for IOAT. We hypothesized that autotransfusion could be safely used for patients undergoing major oncologic procedures and reduce the need for allogeneic blood. MATERIALS AND METHODS: A Phase II, IRB-approved, prospective evaluation was conducted of patients undergoing gastrointestinal oncologic procedures. All procedures were conducted with blood salvaged for IOAT, and the collected volume was autotransfused if it was >100 ml. Quality of life (QoL) was assessed by questionnaire at regular intervals. RESULTS: A total of 92 patients were enrolled with median age of 56 years. The most commonly performed procedures were hepatectomy (47%) and pancreaticoduodenectomy (26%). The median preoperative hemoglobin (Hgb) was 13.1 (range, 9-16), and the median estimated blood loss was 350 ml (range, 20-4000 ml). Of the 92 total patients, 32 (35%) received IOAT with a median volume of 255 ml (range, 117-1499 ml). Multivariate analysis identified that patients with preoperative Hgb >11 g/dl (P = .02), and blood loss of 400-900 ml (P = .03) benefited from IOAT with a reduction in postoperative blood transfusion rate. Patients with discharge Hgb >10 g/dl showed higher mean QoL scores throughout their recovery. At a median follow-up of 18 months, the rates of recurrence in the IOAT and the non-IOAT groups were equivalent (38 vs. 39%, P = .9). CONCLUSIONS: Intraoperative autotransfusion can be used safely and effectively for major oncologic procedures. Furthermore, degree of discharge anemia is associated with lower quality of life in patients undergoing oncologic gastrointestinal surgery.

Irreversible electroporation of the pancreas: definitive local therapy without systemic effects.

BACKGROUND: The use of thermal tumor ablative techniques in the pancreas is limited due to the risk of pancreatitis and damage to major vascular structures. Irreversible electroporation (IRE) is a non-thermal ablation technique that could allow ablation in the pancreas while preserving vital surrounding blood vessels. The aim of this study was to assess the safety and ablation volume of IRE in porcine pancreatic tissue. METHODS: IRE of swine pancreases was performed using an open technique and ultrasound guidance and the animals were followed for 72 hr, 7 days, and 14 days post-IRE. RESULTS: All pigs underwent IRE, with one pig was unsuccessful after three attempts using at 3,000 V due to inability to achieve a stable current. All animals recovered well and revealed only mild adhesions, no ascites, and no pancreatic necrosis. All animals had transient increases in amylase and lipase that normalized on post-IRE day 3. Pathologic analysis revealed that ablation defects (median size 3 cm × 2.8 cm) were seen in electroporated areas with significant destruction of the pancreatic tissue with patent vascular structures. CONCLUSIONS: This animal model demonstrates that IRE of the pancreas performed at an optimal voltage is well tolerated, with rapid resolution of pancreatic inflammation and preservation of vascular structures.

Hepatectomy after hepatic arterial therapy with either yttrium-90 or drug-eluting bead chemotherapy: is it safe?

BACKGROUND: The use of hepatic arterial therapy (HAT) with either yttrium-90 or drug-eluting bead therapy for initially unresectable hepatic malignancies has risen significantly. The safety of hepatic resection after hepatic arterial therapy (HAT) is not established. OBJECTIVE: The present study evaluates the safety profile for hepatic resection after HAT. METHODS: We identified 840 patients undergoing hepatectomy for primary or metastatic lesions. Forty patients underwent HAT before hepatectomy (pre-HAT). A 1:4 case-matched analysis compared three groups: (i) pre-HAT and pre-operative chemotherapy (n=40); (ii) pre-operative chemotherapy (n=160); and (iii) no pre-operative therapy (n=640). Controls were matched for age, resection type, maximal tumour size and magnitude of resection. Morbidity and mortality among groups were compared using a graded complication scale. RESULTS: There were no differences in post-operative complications, grade of complication or liver-specific complications among the groups. A proportional hazards model for all patients did not demonstrate any association between increased complications and either pre-HAT or pre-operative chemotherapy when compared with patients without pre-operative therapy (P=0.7). CONCLUSIONS: Pre-HAT demonstrated similar morbidity, liver-specific morbidity and intra-operative complications when compared with patients undergoing pre-operative chemotherapy alone or without pre-operative chemotherapy. These results suggest that pre-HAT is safe and should not preclude hepatectomy in carefully selected patients.