Citations

Abstract BACKGROUND Spinal muscular atrophy (SMA) is a progressive neuromuscular disorder with neuronal degeneration leading to muscular atrophy and respiratory failure. SMA is frequently caused by homozygous deletions that include exon 7 of the survival motor neuron gene SMN1, and its clinical course is influenced by the copy number of a nearby 5q SMN1 paralog, SMN2. Multiple ligation probe amplification (MLPA) and real-time quantitative PCR (qPCR) can detect SMN1 deletions. Yet, qPCR needs normalization or standard curves, and MLPA demands DNA concentrations above those obtainable from dried blood spots (DBSs). We developed a multiplex, droplet digital PCR (ddPCR) method for the simultaneous detection of SMN1 deletions and SMN2 copy number variation in DBS and other tissues. An SMN1 Sanger sequencing process for DBS was also developed. METHODS SMN1, SMN2, and RPP30 concentrations were simultaneously measured with a Bio-Rad AutoDG and QX200 ddPCR system. A total of 1530 DBSs and 12 SMA patients were tested. RESULTS Population studies confirmed 1 to 5 SMN1 exon 7 copies detected in unaffected specimens, whereas patients with SMA revealed 0 SMN1 copies. Intraassay and interassay imprecisions were <7.1% CV for individuals with ≥1 SMN1 copies. Testing 12 SMA-positive samples resulted in 100% sensitivity and specificity. CONCLUSIONS This ddPCR method is sensitive, specific, and applicable to newborn screening and carrier status determination for SMA. It can also be incorporated with a parallel ddPCR T-cell excision circles assay for severe combined immunodeficiencies.

Background The treatment of lymphatic leaks and lymphoceles in the groin can be challenging with no optimal management determined to date. We postulate that indocyanine green (ICG) lymphangiography improves visualization of the site of a lymphatic leak and can optimize their management. Methods A retrospective review was conducted of all cases in which ICG lymphangiography was used in the management of lymphatic leaks in the groin over an 18-month span. The inciting surgical procedure resulting in the leak was determined. Following thorough debridement, ICG was injected intradermally in the distal extremity and the site of the lymphatic leak was documented (superficial or deep) and oversewn. Outcomes were reported with regard to healing, infection, time to drain removal, and adjunctive procedures. Results Fifteen patients underwent ICG lymphangiography during the surgical treatment of a lymphatic leak in the groin during the study period. In all cases, the site of the lymphatic leak was accurately identified and oversewn. In eight cases, the site of the lymphatic leak was in the subcutaneous tissue superficial to the femoral vessels rather than medial to the femoral vessels in the area of the lymph node basin. A local muscle flap was used in 10 cases simultaneously. All wounds healed primarily without an associated wound or infection. Conclusion ICG lymphangiography facilitated the identification of lymphatic leaks in the groin and optimized their management in these challenging cases, many of which may have been missed if the area around the inguinal lymph node basin was treated exclusively.

Objective: Inadequate work-life balance can have significant implications regarding individual performance, retention, and on the future of the workforce in medicine. The purpose of this study was to determine whether women physicians defer personal life decisions in pursuit of their medical career. Materials and Methods: We conducted a survey study of women physicians ages 20–80 from various medical specialties using a combination of social media platforms and women physicians' professional listservs with 801 survey responses collected from May through November 2015. The primary endpoint was whether women physicians deferred personal life decisions in pursuit of their medical career. Secondary outcomes include types of decisions deferred and correlations with age, hours worked per week, specialty, number of children, and career satisfaction. Results: Respondents were categorized into deferred and nondeferred groups. Personal decision deferments were reported by 64% of respondents. Of these, 86% reported waiting to have children and 22% reported waiting to get married. Finally, while 85% of women in the nondeferment group would choose medicine again as a career, only 71% of women in the deferment group would do so ( p < 0.0001). Physicians who would choose medicine again cited reasons such as career satisfaction, positive patient interactions, and intellectual stimulation, whereas those who would not choose medicine again reported poor work-life balance, decreasing job satisfaction, and insurance/administrative burden. Conclusions: The results of this survey have significant implications on the future of the workforce in medicine. Overall, our analysis shows that 64% of women physicians defer important life decisions in pursuit of their medical career. With an increase in the number of women physicians entering the workforce, lack of support and deferred personal decisions have a potential negative impact on individual performance and retention. Employers must consider the economic impact and potential workforce shortages that may develop if these issues are not addressed.

Abstract Consensus does not exist regarding the best dosage regimen for using tranexamic acid (TXA) for patients undergoing open calvarial vault remodeling in craniosynostosis surgery. The purpose of this study was to evaluate 2 dosing protocols, as well as the cost of using TXA. Previously, the institutional protocol was to give patients undergoing open calvarial vault remodeling a loading infusion of TXA (10 mg/kg) at the start of their procedure, after which intravenous TXA (5 mg/kg/h) was given throughout surgery and for 24 hours postoperatively. In July 2015, the protocol changed to a reduced postoperative infusion time of 4 hours. A retrospective review was conducted of records of 30 patients who had surgery before the protocol change (24-hour group) and 23 patients whose surgery occurred after the protocol change (4-hour group). The following data were collected: blood volume transfused, hemoglobin levels, estimated blood loss, and intensive care days; and costs of TXA and blood transfusion. Results showed a 4-hour infusion was as effective as a 24-hour infusion for reducing blood loss in patients undergoing craniosynostosis. Transfusion requirements, hemoglobin and hematocrit levels, and estimated blood loss were not significantly different for the groups. The cost of TXA and transfusion in the 4-hour group was significantly less (P < 0.001) than in the 24-hour group. No significant difference in cost existed for patients who received blood transfusion alone versus patients who received the 4-hour TXA infusion.

AbstractBackgroundElevated plasma and urine formiminoglutamic acid (FIGLU) levels are commonly indicative of formiminoglutamic aciduria (OMIM #229100), a poorly understood autosomal recessive disorder of histidine and folate metabolism, resulting from formiminotransferase‐cyclodeaminase (FTCD) deficiency, a bifunctional enzyme encoded by FTCD.MethodsIn order to further understanding about the molecular alterations that contribute to FIGLU‐uria, we sequenced FTCD in 20 individuals with putative FTCD deficiency and varying laboratory findings, including increased FIGLU excretion.ResultsIndividuals tested had biallelic loss‐of‐function variants in protein‐coding regions of FTCD. The FTCD allelic spectrum comprised of 12 distinct variants including 5 missense alterations that replace conserved amino acid residues (c.223A>C, c.266A>G, c.319T>C, c.430G>A, c.514G>T), an in‐frame deletion (c.1373_1375delTGG), with the remaining alterations predicted to affect mRNA processing/stability. These included two frameshift variants (c.990dup, c.1366dup) and four nonsense variants (c.337C>T, c.451A>T, c.763C>T, c.1607T>A).ConclusionWe observed additional FTCD alleles leading to urinary FIGLU elevations, and thus, providing molecular evidence of FTCD deficiency in cases identified by newborn screening or clinical biochemical genetic laboratory testing.

AbstractLong‐term outcomes of the Fontan operation include Fontan failure and liver disease. Combined heart‐liver transplantation (CHLT) is an option for select patients although limited data exist on this strategy. A retrospective review of Fontan patients 18 years or older referred for cardiac transplant evaluation between 2000 and 2013 at the Hospital of the University of Pennsylvania was performed. All patients were considered for potential CHLT. Clinical variables such as demographics, perioperative factors, and short‐term outcomes were reviewed. Of 17 referrals for cardiac transplantation, seven Fontan patients underwent CHLT. All patients who underwent CHLT had either advanced fibrosis or cirrhosis on liver biopsy. There were no perioperative deaths. The most common postoperative morbidity was acute kidney injury. Short‐term complications include one episode of acute liver rejection but no cardiac rejection greater than 1R. CHLT is an acceptable therapeutic option for patients with failing Fontan physiology who exhibit concomitant advanced liver fibrosis. However, optimal patient selection is currently undefined, and long‐term outcomes are not known.

Abstract BACKGROUND Newborn screening for lysosomal storage disorders (LSD) has revealed that late-onset variants of these conditions are unexpectedly frequent and therefore may evade diagnosis. We developed an efficient and cost-effective multiplex assay to diagnose six LSDs and several peroxisomal disorders in patients presenting with diverse phenotypes at any age. METHODS Three 3-mm dried blood spot (DBS) punches were placed into individual microtiter plates. One disc was treated with a cocktail containing acid sphingomyelinase-specific substrate and internal standard (IS). To the second DBS we added a cocktail containing substrate and IS for β-glucosidase, acid α-glucosidase, α-galactosidase A, galactocerebrosidase, and α-L-iduronidase. The third DBS was extracted with methanol containing d4-C26 lysophosphatidylcholine as IS and stored until the enzyme plates were combined and purified by liquid–liquid and solid-phase extraction. The extracts were evaporated, reconstituted with the extract from the lysophosphatidylcholine plate, and analyzed by flow injection tandem mass spectrometry. RESULTS Reference intervals were determined by analysis of 550 samples from healthy controls. DBS from confirmed patients with 1 of the 6 LSDs (n = 33), X-adrenoleukodystrophy (n = 9), or a peroxisomal biogenesis disorder (n = 5), as well as carriers for Fabry disease (n = 17) and X-adrenoleukodystrophy (n = 5), were analyzed for assay validation. Prospective clinical testing of 578 samples revealed 25 patients affected with 1 of the detectable conditions. CONCLUSIONS Our flow injection tandem mass spectrometry approach is amenable to high-throughput population screening for Hurler disease, Gaucher disease, Niemann–Pick A/B disease, Pompe disease, Krabbe disease, Fabry disease, X-adrenoleukodystrophy, and peroxisomal biogenesis disorder in DBS.