C0 Levels Research Articles

Prognostic Significance of Early Leukopenia in Heart Transplant Recipients

<h3>Purpose</h3> Although leukopenia is a relatively frequent finding after heart transplantation, its effects on patient outcomes remain poorly defined. We evaluated the long-term prognostic impact of early leukopenia in this patient population. <h3>Methods</h3> We performed a retrospective single-center cohort study in 133 consecutive heart transplant recipients transplanted between January 2009 and September 2016. Recipients with intensified immunosuppression (IS) and patients who died within the first post-transplant year were excluded. All patients received immunoinduction with basiliximab and maintenence IS therapy with tacrolimus (TAC)/mycophenolate mofetil (MMF)/steroids. Infection prophylaxis consisted of posaconasole (6 months), TMP-SMX (life-long) and valgancyclovir (discontinued pending positive Quantiferon-CMV assay). Early leukopenia was defined as any episode of WBC count <4.0x10⁹/L within 12 months after transplantation. Late CMV reactivation was defined as PCR CMV >1000 IU/mL after discontinuation of virostatic therapy. All patients were followed for 5 years. <h3>Results</h3> Within the first post-transplant year, 47 (35%) patients had at least one episode of leukopenia (Group A) and in 86 (65%) no leukopenia was registered (Group B). The two groups did not differ in gender (male; 77% in Group A vs. 86% in Group B, P=0.12), age (57±10 years vs. 54±11 years, P=0.25), heart failure etiology (ischemic: 41% vs. 42%, P=0.97), the presence of hypertension (68% vs. 61%; P=0.34) and diabetes (32% vs. 24%; P=0.23). IS regimen was comparable in both groups and consisted of TAC (mean C0 level 7.4±1.7 μg/mL vs. 7.2±2.1 μg/mL, P=0.41), MMF (mean dose 1979±100 mg vs. 1994±53 mg, P=0.11) and steroids. However, the duration of valgancyclovir therapy was significantly longer in Group A than in Group B (73±143 days vs. 46±97 days, P=0.001). During follow-up, the patients in Group A were more likely to develop malignancy (21% vs. 6% in Group B, P=0.01). We found no differences in late CMV reactivation (12% in Group A vs. 13% in Group B, P=0.98) and 5-year survival (90% vs. 91%; P=0.88) between the two groups. <h3>Conclusion</h3> In heart transplant recipients early leukopenia episodes are likely related to the prolonged use of virostatic therapy and may be associated with increased rates of post-transplant malignancies.

Outcomes of COVID-19 in Heart Transplant Recipients

PurposeData on outcomes after Covid-19 in heart transplant recipients are scarce and inconsistent. We sought to evaluate the early and late post-discharge outcomes in this patient population.MethodsThis case series includes 19 consecutive adult heart transplant recipients hospitalized for Covid-19 at our tertiary center between March 1, 2020 and April 30, 2021. After discharge, all patients were followed per standard post-transplant protocol for 6 months. Significant allograft dysfunction was defined as a decrease in LVEF ≥ 10% and myocardial damage was defined as at least 30% increase in troponin or NT-proBNP serum levels. CMV reactivation was defined as any positive PCR CMV requiring virostatic therapy.ResultsOf 19 recipients 15 (79%) were male with a mean age of 62±8 years and a mean time from transplantation of 4.5±3.4 years. 14 (73%) and 5 (26%) recipients had hypertension and diabetes, respectively. Immunosupressive (IS) regimen at the time of infection consisted of tacrolimus (TAC; mean C0 level 7.5±2.1 μg/mL), mycophenolate mofetil (MMF; mean dose 2052±359 mg) and steroids (mean dose 4.6±4.7 mg). During hospital management IS was reduced in 6 (31%) patients with a maintenence of TAC serum levels (mean C0 7.7±1.9 μg/mL pre-infection vs. 7.5±2.2 μg/mL during infection, P=0.75) and a decrease of MMF dose (2052±359 mg vs. 1906±657 mg, P= 0.01). In 11 (58%) patients we applied oxygen supplementation; however none required non-invasive or invasive forms of ventilation. During hospitalisation 12 (63%) recipients received hyperimmune plasma, 13 (68%) were treated with remdesivir (cumulative dose 600 mg), and 11 (58%) received steroid therapy (mean methylprednisolone dose 29±21 mg). All recipients survived to discharge (mean hospitalization time of 17.4±12.6 days) and to 6-month follow-up. We found no evidence of allograft dysfunction (LVEF 67±6% at baseline vs 68±7% at follow-up; P=0.88) or persistent myocardial damage (troponin: 22±28 pg/mL vs. 14±21 pg/mL; P=0.41 and NT-proBNP: 829±823 pg/mL vs. 817±940 pg/mL; P=0.96). CMV reactivation occured in 3 (16%) recipients and in 1 (5%) recipient a thrombotic event was noted.ConclusionCovid-19 outcomes in heart transplant recipients appear to be acceptable when managed in a tertiary center with dedicated heart transplant and Covid-19 facilities. Further data is needed to establish optimal Covid-19 management algorithms for this patient population.

Efficacy and Safety of mRNA SARS-CoV2 Vaccination in Heart Transplant Recipients

PurposeData on immunologic response to SARS-CoV2 vaccination in heart transplant recipients are scarce. We investigated the efficacy and safety of mRNA SARS-CoV2 vaccination in this patient population.MethodsIn a retrospective single-center study we included 54 consecutive adult heart transplant recipients who received 2 doses of mRNA SARS-CoV2 vaccine between January 1 and June 30, 2021. All patients were followed for 112±28 days after the second dose. At the end of follow-up we measured humoral response to SARS-CoV2 by assessing total antibody levels to the receptor-binding domain of SARS-CoV2 spike (S) protein using anti-RBD immunoassay. Anti-S antibody serum levels ≥250 BAU/mL were considered protective. At the same time, cellular response was measured by the IFN-γ response to S-peptide stimulation of recipient T lymphocyte populations. Protective cellular response was defined as more than 0,3% of IFN-γ responsive T cells.ResultsOf 54 recipients, 44 (81%) were male with a mean age of 63±8 years and a mean time from transplantation of 6.6±4.0 years. Immunosupressive regimen consisted of tacrolimus (mean C0 level 7.4±1.7 μg/mL), mycophenolate mofetil (mean dose 2120±419 mg) and steroids (mean dose 2.5±0.9 mg). The majority of patients received BTN162b2 vaccine (83%), and 17% of recipients were vaccinated with mRNA-1273. During follow-up, a humoral response was present in 24 (44%) of the recipients (median anti-S serum level 35.5 BAU/mL). We found no difference in humoral response between patients receiving BNT162b2 and mRNA-1273 vaccine (median anti-S serum level 68.3 BAU/mL vs. 15.5 BAU/mL, P=0.81). Protective humoral response was observed in 6 (11%) of the recipients (median anti-S serum level 557 BAU/mL). A cellular response to vaccine was present in 3 (6%) of the recipients; all 3 displayed a protective level of reponse. No recipients developed simultaneous protective humoral and cellular responses. Recipient age was the only predictor of protective humoral response (55±11 years in responders vs. 65±8 years in nonresponders; P=0.01). In 3 (6%) recipients we found worsening of allograft function requiring hospital admission, which occured within 1 month after receiving the second dose of vaccine.ConclusionIn heart transplant recipients, mRNA SARS-CoV2 vaccination appears to be of limited efficacy and may, in some cases, be associated with worsening of allograft function.

Newborn Screening for Mitochondrial Carnitine-Acylcarnitine Cycle Disorders in Zhejiang Province, China.

Background: Disorders of mitochondrial carnitine–acylcarnitine cycle is a heterogeneous group of hereditary diseases of mitochondrial β-oxidation of fatty acids tested in NBS program in Zhejiang province, China. Large-scale studies reporting disorders of mitochondrial carnitine–acylcarnitine cycle among Chinese population in NBS are limited. The aim of this study was to explain the incidence and biochemical, clinical, and genetic characteristics of disorders of mitochondrial carnitine–acylcarnitine cycle in NBS. Methods: From January 2009 to June 2021, 4,070,375 newborns were screened by tandem mass spectrometry. Newborns with elevated C0 levels and/or C0/(C16 + C18) ratios were identified as having CPT1D, whereas those with decreased C0 levels and/or C0/(C16 + C18) ratios and/or elevated C12-C18:1 level were identified as having CPT2D or CACTD. Suspected positive patients were further subjected to genetic analysis. All confirmed patients received biochemical and nutritional treatment, as well as follow-up sessions. Results: Overall, 20 patients (12 with CPT1D, 4 with CPT2D, and 4 with CACTD) with disorders of mitochondrial carnitine–acylcarnitine cycle were diagnosed by NBS. The overall incidence of these disorders was one in 203,518 newborns. In toal, 11 patients with CPT1D exhibited increased C0 levels and C0/(C16 + C18) ratios. In all patients of CPT2D, all long chain acyl-carnitines levels were elevated except for case 14 having normal C12 levels. In all patients with CACTD, all long chain acyl-carnitines levels were elevated except for case 17 having normal C12, C18, and C18:1 levels. Most patients with CPT1D were asymptomatic. Overall, two of 4 patients with CPT2D did not present any clinical symptom, but other two patients died. In 4 cases with CACTD, the disease was onset after birth, and 75% patients died. In total, 14 distinct mutations were identified in CPT1A gene, of which 11 were novel and c.1910C > A (p.S637T), c.740C > T (p.P247L), and c.1328T > C (p.L443P) were the most common mutations. Overall, 3 novel mutations were identified in CPT2 gene, and the most frequent mutation was c.1711C > A (p.P571T). The most common variant in SLC25A20 gene was c.199-10T > G. Conclusion: Disorders of mitochondrial carnitine–acylcarnitine cycle can be detected by NBS, and the combined incidence of these disorders in newborns was rare in Zhejiang province, China. Most patients presented typical acylcarnitine profiles. Most patients with CPT1D presented normal growth and development, whereas those with CPT2D/CACTD exhibited a high mortality rate. Several novel CPT1A and CPT2 variants were identified, which expanded the variant spectrum.

Enhanced Remediation of Cd Contaminated Soil by Cotton with DOM

To reveal the effects of dissolved organic matter (DOM) on the remediation of cadmium (Cd)-contaminated soils by cotton, the effects of cotton straw dissolved organic matter (CM) and farmyard manure dissolved organic matter (FM) on soil available Cd (DTPA-Cd) content, cotton biomass, photosynthetic characteristics, and Cd accumulation were investigated in a pot-based experiment under three exogenous soil Cd levels (mg·kg-1) of 0 (C0), 5 (C5), and 10 (C10). The results showed that the application of CM and FM increased the content of available Cd in soil, with the maximum increase of 30.89% and 8.51%, respectively, and that of CM was higher than that of FM. The effects of CM and FM application on total biomass and photosynthetic characteristics in cotton showed that biomass accumulation and net photosynthetic rate were promoted at the C0 level, there was no significant difference compared to that in the control (CK) at the C5 level, and total biomass accumulation and net photosynthetic rate were inhibited at the C10 level; however, transpiration rate both showed higher than the CK treatment at the same Cd level. The application of DOM altered the Cd content of all parts of the cotton compared to that in the CK treatment, where the application of CM resulted in significantly higher Cd content in all parts of the cotton (except for lint) than that in the CK treatment at the same Cd level; however, the application of FM mainly increased the Cd content in the root. The root was the main organ for the increase in total Cd accumulation, the application of CM and FM significantly increased the total Cd accumulation in cotton, and the total Cd accumulation increased by 27.76%-113.05% and 17.77%-93.79%, respectively. Therefore, DOM can be used as an additive to repair Cd-contaminated soil, which has certain application potential. It is recommended to apply cotton straw DOM to repair Cd-contaminated soil.

Investigation and Analysis of Blood Biochemical Indexes and Molecular Biology of Methylmalonic Acidemia.

To compare MMA-related gene mutations in MMA children and the population in Qingdao, discuss the blood propionyl carnitine (C3), free carnitine (C0) methionine (MET), the mutual ratio and division difference in normal group, carrier group, and MMA group to analyze the relationship between some hotspot mutations and biochemical indicators. In total 3,700 newborns testing negative in tandem mass spectrometry (MS/MS) were selected at random and submitted for testing 8 pathogenic sites in MMACHC and 10 in MMUT. The gene mutations in 84 cases with detected mutation genes and 42 diagnosed children were compared. The levels and concentration distribution of C3, C0, MET, C3/C2, C3/C0, C3/MET in the blood samples of three groups were analyzed as well as the difference of biochemical indicators in newborns with hotspot mutations (c.609A>G, c.482G>A, and c.658-660delAAG). All 8 pathogenic mutations in MMACHC in the population were detected and were basically consistent with the mutation types and frequency order in MMA group. The first three were c.609G>A, c.482G>A, and c.658_660delAAG. There were more types of mutation sites detected in MMA group than carrier group. Five out of 10 MMUT gene mutations were detected in the population, and 9 MMUT gene mutation sites were detected in MMA group. The findings in the two groups and the preset sites were not completely consistent. C3, C0, C3/C2, C3/C0, C3/MET in MMA group were higher than carrier and normal groups, and the difference was statistically significant; the MET in MMA group was lower than carrier and normal groups, and the difference was statistical¬ly significant. Based on the three sets of data distribution graphs, C3, C3/C2, C3/C0, and C3/MET were well distinguished. There were differences in the average C3 and C0 levels between carrier and normal groups, but with an obvious cross distribution in the graphs, and no difference in other indicators. In contrast to non-carrier group, C0, C3, C3/C0, C3/C2, and C3/MET concentration levels were higher in 609A>G mutation group, while MET level was lower, with statistical significance; in c.482G>A mutation group, C3, C3/C0, C3/C2, and C3/MET concentration levels were lower than non-carrier group, while MET level was higher, with statistical significance; in c.658-660delAAG mutation group, C0, C3, C3/C0, C3/C2, MET, and C3/MET concentration levels were not statistically different in contrast to other groups. The top three mutations in MMA children in Qingdao area are c.609A>G, c.482G>A, c.658-660del AAG mutations in MMAHC; C3, C3/C2, C3/C0 can be used as specific prompt indicators for MMA screening; C3, C3/C2, C3/C0, C3/MET can be used as specific prompt indicators for combined MMA screening; abnormalities in biochemical indicators in hotspot mutation group intuitively explains c.609A>G mutation and early-onset MMA. c.482G>A mutation links with late-onset MMA.

Effect of CYP3A4, CYP3A5, MDR1 and POR Genetic Polymorphisms in Immunosuppressive Treatment in Chilean Kidney Transplanted Patients.

Cyclosporine (CsA) and tacrolimus (TAC) are immunosuppressant drugs characterized by a narrow therapeutic range and high pharmacokinetic variability. The effect of polymorphisms in genes related to the metabolism and transport of these drugs, namely CYP3A4, CYP3A5, MDR1 and POR genes, has been evaluated in diverse populations. However, the impact of these polymorphisms on drug disposition is not well established in Latin American populations. Using TaqMan® probes, we determined the allelic frequency of seven variants in CYP3A4, CYP3A5, MDR1 and POR in 139 Chilean renal transplant recipients, of which 89 were treated with CsA and 50 with TAC. We tested associations between variants and trough and/or 2-hour concentrations, normalized by dose (C0/D and C2/D) at specific time points post-transplant. We found that CYP3A5*3/*3 carriers required lower doses of TAC. In TAC treated patients, most CYP3A5*3/*3 carriers presented higher C0/D and a high proportion of patients with C0 levels outside the therapeutic range relative to other genotypes. These results reinforce the value of considering CYP3A5 genotypes alongside therapeutic drug monitoring for TAC treated Chilean kidney recipients.

Biochemical and genetic characteristics of patients with primary carnitine deficiency identified through newborn screening

BackgroundPrimary carnitine deficiency (PCD) is an autosomal recessive disorder of carnitine transportation that leads to impaired fatty acid oxidation. Large-scale studies on newborn screening (NBS) for PCD are limited. This study aimed to investigate the biochemical and genetic characteristics of patients with PCD detected through NBS.ResultsA total of 548 247 newborns were screened for PCD between January 2014 and June 2021; 1714 newborns with low free carnitine (C0) levels were called back and 49 patients were diagnosed with PCD. The latest incidence rate in Quanzhou, China, was estimated to be 1 in 11 189 newborns. NBS results showed that the 49 patients had varying degrees of decreased C0 levels, whereas seven patients exhibited normal C0 levels during the recall review. All patients harbored biallelic pathogenic variants of the SLC22A5 gene. Nineteen distinct SLC22A5 variants were detected in these 49 patients, and most of the detected variants were clustered in exons 1, 4, and 7. The top eight variants had an allele frequency of 86.73%. The most common variant was c.760C > T (p.R254*) with an allele frequency of 31.63%, followed by c.51C > G (p.F17L) (17.35%) and c.1400C > G (p.S467C) (16.33%). The C0 level of patients with the N/N genotype was significantly lower than that of the M/M group. The C0 levels of patients with genotypes of R254*/R254* and R254*/F17L were far lower than those of patients with the R254*/S467C genotype.ConclusionsThis study presented more than 500,000 NBS data with the latest incidence of 1:11 189 in the Quanzhou area. The SLC22A5 variant spectrum in the selected southern Chinese population has been updated. Patients with null variants were associated with low C0 levels. Combining NBS with genetic testing is critical to improve screening efficiency because patients with PCD may have normal C0 levels during NBS and recall review.

Biochar combined with phosphate fertilizer application reduces soil cadmium availability and cadmium uptake of maize in Cd-contaminated soils.

Cadmium (Cd) has become the primary pollution factor in farmland, which seriously threatens crop growth and food safety. A pot experiment was conducted to investigate the effect of combined application with biochar and P fertilizer on soil Cd availability and translocation, in which biochar was 0 (C0) and 20gkg-1 (C20), P fertilizer was 0 (P0), 20 (P20), and 40mg P kg-1 (P40). Results showed that, compared with C0 level, the content of DTPA-Cd in soil was significantly decreased with biochar addition after 60days of cultivation, under C20 level, soil DTPA-Cd in C20P40 treatment were significantly increased. Under both C levels, the percentage of exchangeable Cd fraction at P40 rate was significantly lower than that at P20 rate, because the excess P in soil could precipitate Cd. The percentage of residual-Cd fraction was significantly increased with the combined addition of biochar and P fertilizer, particularly in C20P40 treatment, which was 75.95%, while it was only 61.65% in C0P0 treatment. The Cd translocation factor (TF) and bioconcentration factor (BCF) were also significantly reduced in C20P20 and C20P40 treatments compared with C0P0 treatment. Therefore, the combined high P and biochar application was a good choice in inhibiting soil Cd availability and plant Cd uptake, which benefited to the safe utility of the Cd contaminated soil.

Three Novel and One Potential Hotspot CPT1A Variants in Chinese Patients With Carnitine Palmitoyltransferase 1A Deficiency.

Carnitine palmitoyltransferase 1A (CPT1A) deficiency is an inherited disorder of mitochondrial fatty acid β-oxidation that impairs fasting ketogenesis and gluconeogenesis in the liver. Few studies implementing newborn screening (NBS) for CPT1A deficiency in the Chinese population have been reported. This study aimed to determine the biochemical, clinical, and genetic characteristics of patients with CPT1A deficiency in China. A total of 204,777 newborns were screened using tandem mass spectrometry at Quanzhou Maternity and Children's Hospital between January 2017 and December 2018. Newborns with elevated C0 levels were recruited, and suspected patients were subjected to further genetic analysis. Additionally, all Chinese patients genetically diagnosed with CPT1A deficiency were reviewed and included in the study. Among the 204,777 screened newborns, two patients were diagnosed with CPT1A deficiency; thus, the estimated incidence in the selected population was 1:102,388. In addition to the two patients newly diagnosed with CPT1A deficiency, we included in our cohort 10 Chinese patients who were previously diagnosed. Five of these 12 patients were diagnosed via NBS. All patients exhibited elevated C0 and/or C0/(C16+C18) ratios. No clinical symptoms were observed in the five patients diagnosed via NBS, while all seven patients presented with clinical symptoms, including fever, cough, vomiting, diarrhea, and seizures. Eighteen distinct CPT1A variants were identified, 15 of which have been previously reported. The three novel variants were c.272T>C (p.L91P), c.734G>A (p.R245Q), and c.1336G>A (p.G446S). in silico analysis suggested that all three novel variants were potentially pathogenic. The most common variant was c.2201T>C (p.F734S), with an allelic frequency of 16.67% (4/24). Our findings demonstrated that NBS for CPT1A deficiency is beneficial. The three novel variants expand the mutational spectrum of CPT1A in the Chinese population, and c.2201T>C (p.F734S) may be a potential hotspot CPT1A mutation.

Biochemical and molecular features of Chinese patients with glutaric acidemia type 1 detected through newborn screening

BackgroundGlutaric acidemia type 1 (GA1) is a treatable disorder affecting cerebral organic acid metabolism caused by a defective glutaryl-CoA dehydrogenase (GCDH) gene. GA1 diagnosis reports following newborn screening (NBS) are scarce in the Chinese population. This study aimed to assess the acylcarnitine profiles and genetic characteristics of patients with GA1 identified through NBS.Results From January 2014 to September 2020, 517,484 newborns were screened by tandem mass spectrometry, 102 newborns with elevated glutarylcarnitine (C5DC) levels were called back. Thirteen patients were diagnosed with GA1, including 11 neonatal GA1 and two maternal GA1 patients. The incidence of GA1 in the Quanzhou region was estimated at 1 in 47,044 newborns. The initial NBS results showed that all but one of the patients had moderate to markedly increased C5DC levels. Notably, one neonatal patient with low free carnitine (C0) level suggest primary carnitine deficiency (PCD) but was ultimately diagnosed as GA1. Nine neonatal GA1 patients underwent urinary organic acid analyses: eight had elevated GA and 3HGA levels, and one was reported to be within the normal range. Ten distinct GCDH variants were identified. Eight were previously reported, and two were newly identified. In silico prediction tools and protein modeling analyses suggested that the newly identified variants were potentially pathogenic. The most common variant was c.1244-2 A>C, which had an allelic frequency of 54.55% (12/22), followed by c.1261G>A (p.Ala421Thr) at 9.09% (2/22).ConclusionsNeonatal GA1 patients with increased C5DC levels can be identified through NBS. Maternal GA1 patients can also be detected using NBS due to the low C0 levels in their infants. Few neonatal GA1 patients may have atypical acylcarnitine profiles that are easy to miss during NBS; therefore, multigene panel testing should be performed in newborns with low C0 levels. This study indicates that the GCDH variant spectra were heterogeneous in this southern Chinese cohort.

Metabolic acidosis in the initial 6months after renal transplantation: A prospective study.

There is limited information about the incidence of metabolic acidosis (MA) after renal transplantation. This single centre prospective study aimed to delineate the incidence and risk factors of MA in the first 6months after renal transplantation (RTX). Patients who underwent RTX between November 2018 and July 2020 were monitored with weekly measurement of serum bicarbonate level for 6months and those who were diagnosed with MA were evaluated further to characterize the type of MA. One hundred and twenty-five patients were included in the study, 89 (71.2%) of whom developed MA. Seventy-two patients developed MA in the first month, 11 during the 2-3months and 6 between 4 and 6months after transplantation. Of the 89 patients, 55(61.8%) had type 1 renal tubular acidosis (T1RTA), 27 (30.3%) had type 2 RTA (T2RTA) and 7 (7.9%) type 4 RTA (T4RTA). Two patient who had T1RTA, subsequently developed high anion gap MA following severe graft rejection. On stepwise multivariate regression analysis, serum creatinine at time of diagnosis of MA [OR (95% CI): 12.02 (1.79 to 80.59), p=.01] and high tacrolimus C0 levels [OR (95% CI): 2.43 (1.0 to 5.90), p=.049], were independent risk factors for MA. There is a high incidence of MA in the initial 6months post-transplant with serum creatinine and high tacrolimus C0 levels being independent risk factors.

Newborn Screening and Genetic Analysis Identify Six Novel Genetic Variants for Primary Carnitine Deficiency in Ningbo Area, China.

Primary carnitine deficiency (PCD) is an autosomal recessive disorder that could result in sudden death. It is caused by a defect in the carnitine transporter encoded by SLC22A5 (Solute Carrier Family 22 Member 5, MIM:603377). Currently, a number of variants in SLC22A5 have been identified, however, the PCD prevalence and its variants in Ningbo area are unclear. In this study, we screened 265,524 newborns by using tandem mass spectrometry. Variants in SLC22A5 were further detected by next-generation sequencing in individuals with abnormal free carnitine levels (C0). We identified 53 newborns with abnormal C0 levels and 26 with variants in SLC22A5. Among them, 16 with compound heterozygous or homozygous variants in SLC22A5 were diagnosed with PCD, suggesting the PCD birth prevalence in Ningbo city was 1/16,595. Moreover, the C0 level was significantly (P = 0.013) higher in PCD patients than in those with one variant. Besides, the c.1400C > G (p. S467C) and c.51C > G (p. F17L) variants were the most frequent and six novel variants are all predicted to be damaging. This study reports the largest PCD patients in Ningbo area by newborn screening and expands the variant spectrum of SLC22A5. Our findings demonstrate the clinical value of combining NBS program results with DNA analysis for the diagnosis of PCD.

Association of Calculated Area under the Curve or Cyclosporine C0 and C2 Level Monitoring in Pediatric Renal Transplant Patients

Cyclosporine A (CsA) is highly variable pharmacokinetically and has a narrow therapeutic window; the serum level of patients treated with CsA must be monitored carefully. We investigated the trough and second-hour serum levels of CsA, the calculated area under the curve (AUC), and their association of those factors with chronic allograft dysfunction in pediatric patients.

Increased detection of primary carnitine deficiency through second-tier newborn genetic screening

BackgroundNewborn screening for primary carnitine deficiency (NBS) is commonly implemented worldwide; however, it has poor sensitivity. This study aimed to evaluate the feasibility of improving screening by including a second-tier genetic assay.ResultsAn Agena iPLEX assay was developed to identify 17 common SLC22A5 mutations in Chinese populations and was applied in NBS as a second-tier screening. From January 2017 to December 2018, 204,777 newborns were screened for PCD using tandem mass spectrometry. A total of 316 (0.15%) residual NBS-positive specimens with low free carnitine (C0) levels were subjected to this second-tier screening. The screening identified 20 screen-positive newborns who harboured biallelic mutations in theSLC22A5 gene, 99 carriers with one mutation, and 197 screen-negative newborns with no mutations. Among the 99 carriers, four newborns were found to have a second disease-causing SLC22A5mutation by further genetic analysis. Among the 197 screen-negatives were four newborns with persistently low C0 levels, and further genetic analysis revealed that one newborn had two novel SLC22A5 pathogenic variants. In total, 25 newborns were diagnosed with PCD, for a positive predictive value of 7.91% (25/316). Based on these data, we estimate the incidence of PCD in Quanzhou is estimated to be 1:8191.Thirteen distinct SLC22A5 variants were identified, and the most common was c.760C > T, with an allelic frequency of 32% (16/50), followed by c.1400C > G (7/50, 14%), and c.51C > G (7/50, 14%).ConclusionData from this study revealed that 24% (6/25) of PCD cases would have been missed by conventional NBS. This high-throughput iPLEX assay is a powerful tool for PCD genotyping. The addition of this second-tier genetic screening to the current NBS program could identify missed PCD cases, thereby increasing PCD detection. However, further studies are needed to optimise the workflow of the new screening algorithm and to evaluate the cost-effectiveness of this screening approach.

Gene spectrum and clinical traits of 10 patients with primary carnitine deficiency.

BackgroundRare studies focused on the tandem mass spectrometry (MS/MS) findings for the primary carnitine deficiency (PCD) in the neonates in China mainland. In this study, we aim to analyze the gene mutation spectrum of PCD in Fujian Province in China mainland.MethodsPrimary carnitine deficiency (PCD) samples used in this study were selected from 95,453 cases underwent neonatal screening between May 2015 and February 2020. SLC22A5 gene sequencing was performed on the neonates and their parents with C0 level of less than 8.8 μmol/L.ResultsTen patients (male: 7; female: 3) were finally included in this study. Among these patients, nine were neonates, and one was maternal decline of C0 of less than 8.8 μmol/L. The maternal case showed two types of mutations of SLC22A5 including c.760C>T(p.R254*) and c.1400C>G(p.S467C). The other nine neonates showed compound mutations involving nine types in 18 sites, among which two mutations [i.e., c.37G>T(p.E13*) and c.694A>G(p.T232A)] were novel that had never been reported before. Bioinformatic analysis indicated that c.37G>T(p.E13*) was a pathogenic mutation, while the c.694A>G (p.T232A) was considered to be likely pathogenic.ConclusionMS/MS screening on PCD contributed to the early diagnosis and screening. In addition, SLC22A5 gene mutation analysis contributed to the PCD screening.

Tacrolimus therapeutic drug monitoring and correlation with clinical events – A single-center prospective study

Background: Tacrolimus exposure is estimated by trough levels (C0). Recent studies suggest that C0 may not accurately reflect the area under the curve (AUC) and may not correlate with clinical events like acute rejection (AR) and nephrotoxicity. Materials and Methods: In an open, prospective, single-center study, 29 consecutive recipients of renal transplantation underwent C0 along with 2-h (C2), 4-h (C4), and 6-h (C6) estimation of blood tacrolimus levels by enzyme-linked immunosorbent assay, 72 h after initiation with tacrolimus or after a change in its dosage. AUC was estimated by trapezoidal method. C0, C2, C4, and C6 levels were correlated with the AUC. Results: Thirty-six AUC estimations were made over a 2-year period. The best correlate was C6. Correlation coefficients were C0 – 0.868, C2 – 0.788, C4 – 0.839, and C6 – 0.904. C6 values accounted for 79% of the variability of the AUC. Six patients experienced AR, with 5 having C0 within the target range. C6 values correlated best with AUC in these patients (C0 – 0.970, C2 – 0.833, C4 – 0.942, and C6 – 0.970). This was statistically significant. Three patients developed tacrolimus toxicity. In these patients, the correlation coefficients were C0 – 0.551, C2 – 0.556, C4 – 0.77, and C6 – 0.941. By regression analysis, we developed predictive equations. The equation AUC = 12.126 + 2.81 × C0 + 2.92 × C6 best predicted the AUC. Conclusions: Overall C6 levels were more predictive of the AUC, accurately predicting AR and nephrotoxicity. Incorporating C6 may improve tacrolimus therapeutic drug monitoring.

Liraglutide treatment and acylcarnitine profiles in Egyptian obese insulin-resistant females

Using metabolomics technique to investigate the response to liraglutide treatment produces helpful information regarding the effects of drug on metabolic regulation. This study tested whether loss of weight by liraglutide combined with decreasing acylcarnitines (AcylCNs) represent an effective strategy to improve insulin sensitivity in obese insulin-resistant females. AcylCN profiles by tandem mass spectrometry, plasma glycosylated hemoglobin, lactate, pyruvate, serum fasting glucose, creatinine, and insulin were assessed for obese insulin-resistant females before and after treatment with liraglutide for 3 months and non-obese females. All studied parameters in obese insulin-resistant females before treatment were significantly higher than control subjects except C0 and C3 levels which were significantly low. Liraglutide treatment was effective in weight loss, increased C0 and C3 levels and decreased values of all other studied parameters comparing with before treatment but still higher than control. However, creatinine level was unaffected by treatment. This study can conclude that circulating AcylCN profiles can reflect mitochondrial overload that happen in response to obesity. Also, AcylCNs can be used as markers for diagnosis of metabolic disorders. Liraglutide treatment leads to durable improvements in weight reduction and glycometabolic control and the utilization of intracellular glucose.

Remote ischaemic preconditioning influences the levels of acylcarnitines in vascular surgery: a randomised clinical trial

BackgroundVascular surgery patients have reduced tissues` blood supply, which may lead to mitochondrial dysfunction and accumulation of acylcarnitines (ACs).It has been suggested that remote ischaemic preconditioning (RIPC) has its organ protective effect via promoting mitochondrial function.The aim of this study was to evaluate the effect of RIPC on the profile of ACs in the vascular surgery patients.MethodsThis is a randomised, sham-controlled, double-blinded, single-centre study. Patients undergoing open surgical repair of abdominal aortic aneurysm, surgical lower limb revascularisation surgery or carotid endarterectomy were recruited non-consecutively. The RIPC protocol consisting of 4 cycles of 5 min of ischaemia, followed by 5 min of reperfusion, was applied. A blood pressure cuff was used for RIPC or a sham procedure. Blood was collected preoperatively and approximately 24 h postoperatively. The profile of ACs was analysed using the AbsoluteIDQp180 kit (Biocrates Life Sciences AG, Innsbruck, Austria).ResultsNinety-eight patients were recruited and randomised into the study groups and 45 patients from the RIPC group and 47 patients from the sham group were included in final analysis. There was a statistically significant difference between the groups regarding the changes in C3-OH (p = 0.023)—there was a decrease (− 0.007 µmol/L, ± 0.020 µmol/L, p = 0.0233) in the RIPC group and increase (0.002 µmol/L, ± 0.015 µmol/L, p = 0.481) in the sham group. Additionally, a decrease from baseline to 24 h after surgery (p < 0.05) was detected both in the sham and the RIPC group in the levels of following ACs: C2, C8, C10, C10:1, C12, C12:1, C14:1, C14:2, C16, C16:1, C18, C18:1, C18:2. In the sham group, there was an increase (p < 0.05) in the levels of C0 (carnitine) and a decrease in the level of C18:1-OH. In the RIPC group, a decrease (p < 0.05) was noted in the levels of C3-OH, C3-DC (C4-OH), C6:1, C9, C10:2.ConclusionsIt can be concluded that RIPC may have an effect on the levels of ACs and might therefore have protective effects on mitochondria in the vascular surgery patients. Further larger studies conducted on homogenous populations are needed to make more definite conclusions about the effect of RIPC on the metabolism of ACs.Trial registrationClinicalTrials.gov database, NCT02689414. Registered 24 February 2016—Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT02689414.

Newborn screening for primary carnitine deficiency and variant spectrum of SLC22A5 gene in Guangzhou

Objective: To evaluate and improve the performance of the newborn screening program for primary carnitine deficiency (PCD) based on tandem mass spectrometry and to investigate the incidence of PCD and molecular characteristics of SLC22A5 gene in Guangzhou. Methods: A total of 200 180 neonates born in Guangzhou from 2015 to 2019 were enrolled into the newborn screening program for PCD by tandem mass spectrometry at Guangzhou Newborn Screening Center. The positive results of screening for PCD was defined as free carnitine (C0) less than 10 μmol/L with decreased acylcarnitine species in dried blood spots of three to seven days after birth. Screen-positive newborns and their mothers were recalled for another blood spot sample. The diagnosis was confirmed based on decreased levels of C0 and acylcarnitine species in recalled blood spots and genetic analysis in SLC22A5 gene sequencing. The utility of using the sum of propionylcarnitine and palmitoylcarnitine (C3+C16) as a biomarker for acylcarnitine species in newborn screening was retrospectively evaluated. The levels of C0 and (C3+C16) at first screening were compared between newborns with PCD and newborns born to mothers with PCD by independent t test. The variant spectrum and known pathogenic variants carrier rate of SLC22A5 in 2 395 healthy children in Guangzhou Women and Children's Medical Center through whole exon sequencing were analyzed. Results: Among 200 180 neonates, 239 (0.12%) cases were screen-positive for PCD. A total of 37 patients including 15 newborns and 22 mothers had confirmed PCD. The incidence of PCD was 1/13 345 in newborns and 1/9 099 in mothers, respectively. The positive predictive value of this program was 15.5%. Taking cutoff values of C0<8.5 μmol/L or C0 8.5~9.9 μmol/L with (C3+C16)<2 μmol/L, the number of screen-positive cases would be reduced from 810 to 224 without additional false negative case, when compared with cutoff value C0<10 μmol/L only. Both levels of C0 and (C3+C16) at first screening were not significant difference between newborns with PCD and newborns born to mothers with PCD ((6.2±2.4) vs. (5.0±1.8) μmol/L, (1.4±0.4) vs. (1.2±0.5) μmol/L, t=3.826, 0.326; P=0.058, 0.572). Seven PCD mothers experienced moderate fatigue and dizziness in the morning. One of them presented with cardiomyopathy in pregnancy. Genetic analysis of the SLC22A5 gene showed that p.S467C, p.F17L, p.R254X were the three most common variants in newborns with PCD. In PCD mothers and healthy children, the p.S467C, p.F17L and R399W were the three most common whereas the severe variant p.R254X was rare. The population carrier rate for pathogenic variants was 1 in 65 and the estimated incidence of PCD was about 1/16 500. Conclusions: Newborn screening can detect PCD both in newborns and mothers. Adding a quantitative biomarker (C3+C16) <2 μmol/L into the newborn screening program can improve the PCD screen performance. The severe variant p.R253X was common in PCD newborns but rare in PCD mothers and healthy children, indicating that the current screening program maybe failed to detect all PCD newborns and under-estimated the incidence rate of PCD in Guangzhou.