Six SIGMA evaluation of 17 biochemistry parameters using bias calculated from internal quality control and external quality assurance data.

Background: Six Sigma is a popular quality management system that enables continuous monitoring and improvement of analytical performance in the clinical laboratory. We aimed to calculate sigma metrics and quality goal index (QGI) for 17 biochemical analytes and compare the use of bias from internal quality control (IQC) and external quality assurance (EQA) data in the calculation of sigma metrics. Methods: This retrospective study was conducted in Marmara University Pendik E&R Hospital Biochemistry Laboratory. Sigma metrics calculation was performed as (TEa-bias)/CV). CV was calculated from IQC data from June 2018 - February 2019. EQA bias was calculated as the mean of % deviation from the peer group means in the last seven surveys, and IQC bias was calculated as (laboratory control result mean-manufacturer control mean)/ manufacturer control mean) x100. In parameters where sigma metrics were <5; QGI=bias/1.5 CV) score of <0.8 indicated imprecision, >1.2 pointed inaccuracy, and 0.8-1.2 showed both imprecision and inaccuracy. Results: Creatine kinase (both levels), iron and magnesium (pathologic levels) showed an ideal performance with ≥6 sigma level for both bias determinations. Eight of the 17 parameters had different sigma levels when we compared sigma values calculated from EQA and IQC derived bias% while the rest were grouped at the same levels. Conclusions: Sigma metrics is a good quality tool to assess a laboratory's analytical performance and facilitate the comparison of the assay performances in the same manner across multiple systems. However, we might need to design a tight internal quality control protocol for analytes showing poor assay performance.

Development of external genitalia during mini-puberty: is it related to somatic growth or reproductive hormones?

Although hypothalamo-pituitary-gonadal axis is active during mini-puberty, its relationship with somatic growth and the role on the development of external genitalia has not been fully elucidated. We aimed to evaluate the effects of somatic growth and reproductive hormones on the development of external genitalia during mini-puberty. Anthropometric data, pubertal assesment, serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), dehydroepiandrosterone sulfate (DHEAS), androstenedione (A4), sex-hormone binding globulin (SHBG), estradiol (E2) and inhibin-B, testosterone (T), and anti-Mullerian Hormone (AMH) of healthy infants aged 1-4 months were evaluated. Free sex hormone index was calculated as T/SHBG for boys and E2/SHBG for girls. The mean age of 148 (74 female) infants included in the study was 2.31 ± 0.76 months. Tanner stage 2-3 sex steroid and gonadotropin levels were observed. A statistically significant difference was found between the weight, height, BMI, weight gain and serum FSH, LH, and A4 measurements of girls and boys (p < 0.05). Penile length was associated with weight (r = 0.24, p = 0.03), height (r = 0.25, p = 0.02), and AMH (r = 0.3, p = 0.01), but not with testosterone (p = 0.56 respectively). A negative correlation was found between weight and serum LH (r = - 0.26, p = 0.2) and T/SHBG levels in males (r = - 0.38, p = 0.015 respectively). Weight-SDS was negatively correlated with testosterone in males (r = - 0.25, p = 0.02). Testicular size and breast stage did not correlate with any of the hormonal and anthropometric parameters.  Conclusions: External genitalia in males during mini-puberty is related more to somatic growth rather than reproductive hormones. Similar to pubertal developmental stages, both total and free testosterone are negatively associated with higher weight during mini-puberty. What is Known: • Mini-puberty allows early assessment of HPG axis function in infancy. • There is an inverse relationship between the amount of adipose tissue and circulating testosterone levels in males during puberty and adulthood. • The potential effect of somatic growth and reproductive hormones on external genital development during mini-puberty remains unclear. What is New: • During mini-puberty, males' external genitalia is more related to somatic growth than to reproductive hormones, but this relationship is not observed in girls. • Both total and free testosterone are negatively associated with higher weight during mini-puberty, similar to the pubertal developmental stages.

Angiotensin-Converting Enzyme (ACE) level, but not ACE gene polymorphism, is associated with prognosis of COVID-19 infection: Implications for diabetes and hypertension.

BACKGROUND: The renin-angiotensin-aldosterone system was shown to be activated in severe COVID-19 infection. We aimed to investigate the relationship between angiotensin converting enzyme (ACE) levels, ACE gene polymorphism, type 2 diabetes (T2DM), and hypertension (HT) and the prognosis of COVID-19 infection. METHODS: This cross-sectional study analyzed the clinical features of adult patients with SARS-CoV-2 infection. ACE gene analysis and ACE level measurements were performed. The patients were grouped according to ACE gene polymorphism (DD, ID or II), disease severity (mild, moderate, or severe), and the use of dipeptidyl peptidase-4 enzyme inhibitor (DPP4i), ACE-inhibitor (ACEi) or angiotensin receptor blocker (ARB). Intensive care unit (ICU) admissions and mortality were also recorded. RESULTS: A total of 266 patients were enrolled. Gene analysis detected DD polymorphism in the ACE 1 gene in 32.7% (n = 87), ID in 51.5% (n = 137), and II in 15.8% (n = 42) of the patients. ACE gene polymorphisms were not associated with disease severity, ICU admission, or mortality. ACE levels were higher in patients who died (p = 0.004) or were admitted to the ICU (p<0.001) and in those with severe disease compared to cases with mild (p = 0.023) or moderate (p<0.001) disease. HT, T2DM, and ACEi/ARB or DPP4i use were not associated with mortality or ICU admission. ACE levels were similar in patients with or without HT (p = 0.374) and with HT using or not using ACEi/ARB (p = 0.999). They were also similar in patients with and without T2DM (p = 0.062) and in those with and without DPP4i treatment (p = 0.427). ACE level was a weak predictor of mortality but an important predictor of ICU admission. It predicted ICU admission in total (cutoff value >37.092 ng/mL, AUC: 0.775, p<0.001). CONCLUSION: Our findings suggest that higher ACE levels, but not ACE gene polymorphism, ACEi/ARB or DPP4i use, were associated with the prognosis of COVID-19 infection. The presence of HT and T2DM and ACEi/ARB or DPP4i use were not associated with mortality or ICU admission.

Immunogenicity, efficacy, and safety of CoronaVac and Pfizer/BioNTech mRNA vaccines in patients with psoriasis receiving systemic therapies: A prospective cohort study.

BACKGROUND AND OBJECTIVES: Evidence of immune response to COVID-19 vaccine in psoriasis patients on biological agents is lacking. This study aimed to evaluate SARS-CoV-2 antibody levels following vaccination with CoronaVac or Pfizer/BioNTech mRNA in patients using biological agents or methotrexate, high-titer antibody levels achievement rate, and impact of medications on immunogenicity. METHODS: This noninterventional, prospective cohort study included 89 patients and 40 controls vaccinated with two doses of inactivated (CoronaVac) or Pfizer/BioNTech mRNA vaccines. Anti-spike and neutralising antibodies were analysed before and three to six weeks after the second dose. Adverse effects and symptomatic COVID-19 were assessed. RESULTS: Median anti-spike and neutralising antibody titers after CoronaVac were significantly lower in patients than controls (57.92 U/mL vs 125.4 U/mL, and 1/6 vs 1/32, respectively, p < 0.05). Patients were less likely to achieve high-titer anti-spike antibody levels (25.6 % vs 50 %). Infliximab was associated with attenuated vaccine response. Pfizer/BioNTech vaccine induced comparable median anti-spike (2,080 U/mL vs 2,976.5 U/mL,) and neutralising antibody levels (1/96 vs 1/160) in patients and controls, respectively (p > 0.05). High-titer anti-spike and neutralising antibodies development rates were comparable among patients and controls (95.2 % vs 100 %, and 30.4 % vs 50.0 %, respectively, p > 0.05). Nine (10.1 %) COVID-19 cases- all mild - were identified. Psoriasis flare was seen in 6.74 %, mostly after Pfizer/BioNTech vaccine. CONCLUSION: Psoriasis patients treated with biological agents and methotrexate developed similar response to mRNA vaccine but weaker response to inactivated vaccine. Infliximab reduced response to the inactivated vaccine. Adverse effects were more frequent with mRNA vaccine, but none was severe.

Diagnostic performance of lactate dehydrogenase (LDH) isoenzymes levels for the severity of COVID-19.

Background: Lactate dehydrogenase (LDH) levels predict coronavirus disease 2019 (COVID-19) severity. We investigated LDH isoenzyme levels to identify the tissue responsible for serum LDH elevation in patients with COVID-19. Methods: Hospitalised COVID-19 patients with serum LDH levels exceeding the upper reference limit included. LDH isoenzymes were detected quantitatively on agarose gels. The radiological severity of lung involvement on computed tomography was scored as 0-5 for each lobe (total possible score, 0-25). Disease severity was determined using the World Health Organization (WHO) clinical progression scale. Results: In total, 111 patients (mean age, 59.96 ± 16.14), including 43 females (38.7%), were enrolled. The serum levels of total LDH and all five LDH isoenzymes were significantly higher in the severe group. The levels of all LDH isoenzymes excluding LDH5 positively correlated with the WHO score. LDH3 levels correlated with chest computed tomography findings (r2 = 0.267, p = 0.005). On multivariate analysis, LDH3 was an independent risk factor for the deterioration of COVID-19. Conclusions: LDH3 appears to be an independent risk factor for deterioration in patients with COVID-19. LDH elevation in patients with COVID-19 predominantly resulted from lung, liver and muscle damage.

Serum and vitreous vascular endothelial growth factor levels in diabetic retinopathy.

PURPOSE: To research whether serum vascular endothelial growth factor (VEGF) levels could be used to evaluate diabetic retinopathy (DR) progression and to compare vitreous VEGF levels after injections of intravitreal bevacizumab (IVB), ranibizumab (IVR), and triamcinolone acetonide (IVTA) in proliferative diabetic retinopathy (PDR). METHODS: We enrolled a total of 91 eyes of 89 subjects (70 eyes of 68 diabetics and 21 eyes of 21 non-diabetic controls). The diabetic subjects were divided into three groups as PDR (n = 28), non-proliferative diabetic retinopathy (n = 20), and no-DR (n = 20). Eyes with PDR (n = 31) were injected with IVB (n = 7), IVR (n = 10), or IVTA (n = 6) 3 days before vitrectomy, and eight eyes did not receive an injection. Serum and vitreous samples were collected before vitrectomy and analyzed using ELISA. RESULTS: We found the severity of retinopathy was not correlated with serum VEGF levels (P = .919, ρ = -0.011). Compared with the controls, vitreous VEGF was higher in the PDR (P < .001), whereas serum VEGF did not differ (P = .99). The controls had lower vitreous VEGF than the IVB, IVR, and no-injection subgroups (P = .01, P < .001, and P = .04, respectively). Vitreous VEGF was similar among the injected and no-injection subgroups (P = .17). CONCLUSIONS: Serum VEGF levels may not directly reflect retinopathy progression. Neither IVB, IVR nor IVTA could eliminate vitreous VEGF levels within 3 days before vitrectomy.

Evaluation of the Diagnostic Value of Cell Population Data in Sepsis in Comparison to Localized Infection, Chronic Inflammation, and Noninfectious Inflammation Cases.

INTRODUCTION: Sepsis, defined as an increase of 2 points or more in the sequential organ failure assessment score, is a life-threatening organ dysfunction caused by the dysregulated host response to infection. Volume-conductivity-scatter (VCS) parameters of cell counters which are known as cell population data (CPD) have been suggested to be beneficial in diagnosing sepsis. We aimed to evaluate the diagnostic value of CPD parameters in sepsis in comparison to nonsystemic infection cases (NSI) and non-infectious acute and chronic inflammatory conditions. MATERIALS AND METHODS: We prospectively included four groups of patients" data: sepsis (n = 66), localized infection (pneumonia, n = 59), chronic inflammation (rheumatoid arthritis, n = 92) and noninfectious inflammation (coronary artery bypass graft operation, n = 56) groups, according to their clinical status and laboratory results. Samples for cell counting and serum markers were collected on the same day of culture collection. VCS parameters were measured by Unicel DxH800 Coulter Cellular Analyzer (Beckman Coulter, USA). RESULTS: Mean neutrophil volume (MN-V-NE), was highest in the sepsis group [155(149-168)] compared to the localized infection [148(140-158)], chronic inflammation [144.5(142-149)] and noninfectious inflammation [149(145.2-153.7)] (P = 0.001, P < 0.001, P < 0.001, respectively). Neutrophil volume SD (SD-V-NE) was higher in the sepsis [21(18.8-23.7)], significantly differentiating sepsis from other groups. The area under curves of procalcitonin and hs-C-reactive protein were 0.846 and 0.837, respectively, in the receiver-operating characteristic curves (ROC) . CPD combinations, (SD-V NE + SD-V LY + SD-V MO), (SD-V NE + SD-V MO), and (MN-V NE + SD-V NE + SD-C LY + SD-V MO) had greater AUC values than procalcitonin's. CONCLUSION: VCS parameters might be promising for differentiating sepsis and non-sepsis cases. Additionally, obtaining these data routinely makes their prospects promising without any additional cost and time.

Phoenixin 14 ameloriates pancreatic injury in streptozotocin-induced diabetic rats by alleviating oxidative burden.

Phoenixin-14 (PNX) is a neuropeptide that has been shown to prevent oxidative damage and stimulates insulin secretion. We investigated the effects of PNX on pancreatic injury induced by streptozotocin (STZ), and nicotinamide (NAD). Male Sprague-Dawley rats, in control (C) and diabetic (STZ) groups, were treated with either saline, or PNX (0.45 nmol/kg, or 45 nmol/kg) daily for 3 days 1 week after STZ injection. Fasting blood glucose (FBG) and gastric emptying rate (GER) were measured. Tissue and blood samples were collected. PNX treatments prevented pancreatic damage and ß cell loss. Increased luminol and lucigenin levels in the pancreas, ileum and liver tissues of STZ groups were alleviated by PNX treatment in pancreatic and ileal tissues. PNX0.45 decreased FBG without any change in insulin blood level and pancreatic mRNA. GER increased in all diabetic rats while PNX0.45 delayed GER only in the C group. PNX diminishes pancreatic damage and lowers FBG by reducing oxidative load.

Free and Bioavailable Vitamin D Levels of Patients with Type 1 Diabetes Mellitus and Association with Bone Metabolism.

Aim: Vitamin D deficiency is known to be associated with metabolic bone diseases. The aim of this study is to evaluate vitamin D and calculated free and bioactive vitamin D levels of type 1 diabetic patients and to evaluate the association with bone turnover markers. Method: This cross-sectional study includes 60 patients admitted to endocrinology outpatient clinic with diagnosis of type 1 diabetes mellitus and 60 controls. Weight, height and waist circumference were recorded and blood samples were taken for measurement of 25-hydroxyvitamin D (25(OH)D), vitamin D binding protein (VDBP), osteocalcin, bone alkaline phosphatase (bone-ALP), c-telopeptide. Free and bioavailable vitamin D levels were calculated with formula. Results: Vitamin D levels of type 1 diabetic patients were significantly higher (p = 0.01). Parathormone levels of the group with vitamin D level under 20 ng/ml was significantly higher (p = 0.029). VDBP levels were similar in both groups. Correlation analysis of free and bioavailable vitamin D level with osteocalcin, c-telopeptide, bone alkaline phosphatase revealed only a weak significant correlation between free vitamin D and osteocalcin (r = -0.201; p = 0.028). A negative correlation was determined between 25(OH)D and parathormone levels (r = -0.294; p < 0.005). Serum osteocalcin, bone alkaline phosphatase and c-telopeptide levels of control group were significantly higher. Conclusion: 25(OH)D levels of the study population was extremely low. The measurement of VDBP and calculated free and bioactive vitamin D levels did not show a better correlation with bone turnover markers according to 25(OH)D levels.

Accurate interpretation of thyroid dysfunction during pregnancy: should we continue to use published guidelines instead of population-based gestation-specific reference intervals for the thyroid-stimulating hormone (TSH)?

BACKGROUND: Considering the changes in thyroid physiology associated with pregnancy and poor outcomes related to abnormal maternal thyroid function, international guidelines recommend using population-based trimester-specific reference intervals (RIs) for thyroid testing. If these RIs are not available in the laboratory, implementing recommended fixed cut-off values globally is still controversial. To address this issue, we aimed to establish appropriate RI of thyroid-stimulating hormone (TSH) in pregnant Turkish women for our laboratory and compare the prevalence of thyroid dysfunction based on the established and recommended criteria. METHODS: Of 2638 pregnant women, 1777 women followed in the obstetric outpatient were enrolled in the reference interval study after applying exclusion criteria related to medical and prenatal history. A retrospective study was conducted by collecting data from July 2016 to March 2019. Serum TSH was measured by UniCel DxI 800 Immunoassay System (Beckman Coulter Inc., Brea, CA, USA). The study design relied on two approaches in order to classify pregnant women: trimester-specific and subgroup-specific; the latter involved dividing each trimester into two subgroups: T1a, T1b, T2a, T2b, T3a, T3b. The lower and upper limits of the RIs were derived by the parametric method after normalizing the data distribution using the modified Box-Cox power transformation method. RESULTS: The lowest TSH value was detected at 8-12 weeks in early pregnancy, and the median value of TSH in the T1b subgroup was significantly lower than the T1a subgroup (P < 0.05). TSH levels showed a gradual trend of increase along with the pregnancy and increased significantly in the T2a, T2b, and T3b subgroups compared to the preceding subgroups (P < 0.05). Compared to the diagnostic criteria recommended by American Thyroid Association (ATA), the prevalence of thyroid dysfunction was significantly different from the established trimester- and subgroup-specific RIs throughout the pregnancy (P < 0.001). CONCLUSIONS: We conclude that establishing gestation- and laboratory-specific RIs, especially for TSH, is essential for diagnosing thyroid disorders in pregnancy, and the recommended universal cut-off values, which may contribute to the risk of a misdiagnosis or a missed diagnosis, should be taken with caution in the clinical setting. However, regarding the fluctuation of thyroid function tests throughout pregnancy, trimester-specific RIs are insufficient, and implementing split phases is required.

The effect of immunization with inactivated SARS-CoV-2 vaccine (CoronaVac) and/or SARS-CoV-2 infection on antibody levels, plasmablasts, long-lived-plasma-cells, and IFN-γ release by natural killer cells.

OBJECTIVES: We evaluated the antibody response, natural killer cell response and B cell phenotypes in healthcare workers (HCW) who are vaccinated with two doses of CoronaVac with or without documented SARS-CoV-2 infection and unvaccinated HCWs with SARS-CoV-2 infection. METHODS: HCWs were divided into four groups: vaccine only (VO), vaccine after SARS-CoV-2 infection (VAI), SARS-CoV-2 infection only (IO), and SARS-CoV-2 infection after vaccine (IAV). Anti-SARS-CoV-2 spike protein (Anti-S) antibodies were measured by Elecsys Anti-SARS-CoV-2 S ELISA kit. Memory B cells (CD19+CD27+), plasmablast B cells (CD19+CD138+) and long-lived plasma cells (LLPC; CD138+CD19-) were measured by flow cytometry in 74 patients. Interferon gamma (IFN-γ) release by natural killer (NK) cells were measured by NKVue Test (NKMAX, Republic of Korea) in 76 patients. RT-PCR was performed with Bio-speedy® COVID-19 qPCR detection kit, Version 2 (Bioexen LTD, Istanbul, Turkey). RESULTS: The Anti-S antibodies were detectable in all HCWs (n: 224). The median Anti-S titers (BAU/mL) was significantly higher in VAI (620 25-75% 373-1341) compared to VO (136, 25-75% 85-283) and IO (111, 25-75% 54-413, p < 0.01). VAI group had significantly lower percentage of plasmablasts (2.9; 0-8.7) compared to VO (6.8; 3.5-12.0) and IO (9.9; 4.7-47.5, p < 0.01) (n:74). Percentage of LLPCs in groups VO, VAI and IO was similar. There was no difference of IFN-γ levels between the study groups (n: 76). CONCLUSION: The antibody response was similar between uninfected vaccinated HCWs and unvaccinated HCWs who had natural infection. HCWs who had two doses of CoronaVac either before or after the natural SARS-CoV-2 infection elicited significantly higher antibody responses compared to uninfected vaccinated HCWs. The lower percentages of plasmablasts in the VAI group may indicate their migration to lymph nodes and initiation of the germinal center reaction phase. IFN-γ response did not differ among the groups.

The association of free testosterone levels with coronavirus disease 2019.

BACKGROUND: Angiotensin-converting enzyme 2 and transmembrane protease serine 2 are critical factors of virus transmission. Expression of angiotensin-converting enzyme 2 is highest in testes, and testicular function and testosterone levels were affected by coronavirus disease 2019. Low testosterone levels are related to infections, especially respiratory tract infections, and could worsen clinical conditions by exacerbating cytokine storms and increasing pro-inflammatory cytokines. OBJECTIVES: We aimed to evaluate the acute and chronic effects of coronavirus disease 2019 on gonadal functions. Our second aim was to detect the relationship between free testosterone levels and disease prognosis and determine the impact of low-free testosterone on admission to the intensive care unit. METHODS: Eighty-one patients with reverse-transcription polymerase chain reaction-confirmed coronavirus disease 2019 were enrolled. Twenty-nine patients were assessed again for 6 months post-coronavirus disease 2019 follow-up, and seven of them had a semen analysis. Serum follicle-stimulating hormone, luteinizing hormone, sex hormone-binding globulin, and total testosterone levels were measured. RESULTS: In this observational study, 71.6% (n = 58) of patients had low free testosterone levels at baseline, in which 69% were considered secondary hypogonadism. A longer length of hospitalization and increased inflammatory markers (d-dimer, high-sensitive C-reactive protein, and procalcitonin) were detected in the low-free testosterone group. Follicle-stimulating hormone, total, free, and bioavailable testosterone levels were lower in patients who required admission to the intensive care unit. Free testosterone levels were inversely correlated with the length of hospitalization and prognostic disease factors. Oligozoospermia and impaired progressive motility were present in 42.8% (3/7) of the patients. In 6 months post-coronavirus disease 2019 follow-up, out of 29 patients, 48.2% still had low testosterone levels. CONCLUSION: A high rate of hypogonadism (71.6%) was found, especially secondary hypogonadism, and about half of the patients had hypogonadism in the sixth months' follow-up. Low free testosterone levels were correlated with inflammatory parameters, and it is related to the intensive care unit admission. Studies with long-term follow-up data in larger groups are needed to determine persistent hypogonadism and impaired spermatogenesis.

Does concomitant prolactin measurement increase the accuracy of inferior petrosal sinus sampling?

INTRODUCTION: Prolactin (PRL) measurement during inferior petrosal sinus sampling (IPSS) can be helpful to improve the accuracy. We aimed to evaluate the effect of measuring PRL levels as a predictor for the accuracy of IPSS and evaluate its impact on the lateralization of adenomas. METHODS: In this retrospective cohort study, we reviewed 51 patients who had undergone IPSS for the investigation of ACTH-dependent hypercortisolism. RESULTS: Forty-nine patients had proven Cushing's disease (CD), one had EAS, and the remaining one patient had adrenal adenoma. Forty-seven patients had an above 2 ACTH IPS/P ratio at baseline, and all the post-corticotropin-releasing hormone (CRH) ACTH IPS/P ratios of patients with proven CD were above 3. In these two patients whose ACTH IPS/P ratio at baseline was below 2, PRL IPS/P ratios were above 1.8 in only the dominant side, which was considered secondary to a prolactin intersinus gradient due to the biological effects of the tumor. PRL-adjusted ACTH IPS/P ratios were > 1.3 in all patients with proven CD; it was 0.7 in the patient with EAS. Surgically confirmed positive lateralization was observed in 55.1% of patients with the ACTH gradient, but when PRL-adjusted ACTH IPS/IPS ratios were used in addition to the ACTH gradient, the ratio increased to 67.3%. CONCLUSION: Although PRL-adjusted ACTH IPS/P ratios can be helpful to improve the accuracy of results during IPSS procedures, a prolactin intersinus gradient towards the ACTH-dominant side in patients with CD may invalidate PRL as an indicator of pituitary venous outflow.

Effects of vitamin D receptor gene polymorphisms on the prognosis of COVID-19.

PURPOSE: Vitamin D deficiency has emerged as another potential risk factor for coronavirus disease (COVID-19) due to the immunomodulatory effects of 25 hydroxyvitamin D [25 (OH)D]. Vitamin D receptor (VDR) gene polymorphisms such as Fok I, Bsm I, Apa I, and Taq I are also associated with different courses of viral infections. This study aimed to evaluate the association between the VDR gene polymorphism at Fok I, Taq I, Bsm I, and Apa I genotypes and the prognosis of COVID-19 in respect to vitamin D deficiency. METHODS: Two-hundred ninety-seven patients with COVID-19 were enrolled. Serum 25 (OH)D levels were measured. Four variant regions of the VDR gene, FokI, BsmI, ApaI, and TaqI were determined. RESULTS: Eighty-three percent of subjects had vitamin D deficiency, and 40.7% of the whole group had severe deficiency. Median 25 (OH)D level was 11.97 ng/ml. Vitamin D levels were not related to inflammatory markers, disease severity, admission to intensive care unit (ICU), and mortality. While disease severity was related to Fok I Ff genotype, it was Taq TT genotype for ICU admission. Moreover, the ApaI aa genotype was common among the patients who were died. None of the deceased subjects had the Fok I FF genotype. CONCLUSION: 25 (OH)D levels were not related to the severity and mortality of COVID-19. VDR gene polymorphisms are independently associated with the severity of COVID-19 and the survival of patients.

Adrenal steroids reference ranges in infancy determined by LC-MS/MS.

BACKGROUND: Interpretation of the results of steroid hormone measurements is challenging at early infancy. The liquid chromatography-tandem mass spectrometry (LC-MS/MS) method provides a powerful tool for diagnosing steroidogenesis disorders. We aimed to develop normative data for a 14-steroid panel and four adrenal enzyme activity indices, determined by LC-MS/MS from 3 days to 6 months of age. METHODS: Age- and sex-specific plasma steroid concentrations were calculated in 324 healthy full-term neonates and infants (151 females). Percentile curves were devised. Steroid ratios were evaluated as biomarkers of adrenal enzyme activities. The steroid profiles of four patients with adrenal enzyme deficiencies were included to test the diagnostic efficiency. RESULTS: Nine steroids showed age, but none showed sex specificity. The concentrations of progestins and androgens were higher at 7-14 days than at 3-7 days. After the first month, adrenal androgen concentrations decreased significantly. Adrenal enzyme activities changed towards increasing cortisol over the first 6 months. There were several-fold differences in diagnostic steroids and related adrenal enzyme activity indices between the patients and the healthy group. CONCLUSIONS: The majority of adrenal steroids show age-related variations in the neonatal period and early infancy. Our data will enable accurate interpretation of steroid measurements for etiologic diagnosis of disorders of steroidogenesis. IMPACT: LC-MS/MS method is capable of quantitating numerous analytes simultaneously, which provides an integrated picture of adrenal steroidogenesis in a small amount of sample. The development of LC-MS/MS-based normative data of steroid hormones in healthy infants is crucial to differentiate physiologic alterations from steroidogenic defects during the first 3-6 months of infancy. Previous studies had limitations due to the small numbers of samples available by sex and by age groups. Our detailed normative data and percentile curves will enable accurate interpretation of steroid measurements for etiologic diagnosis of disorders of steroidogenesis without the need for further invasive testing.

Serum osteoprotegerin levels, endothelial function and carotid intima-media thickness in type 2 diabetic patients.

OBJECTIVES: Osteoprotegerin (OPG), a well-known protein that inhibits osteoclast formation and activity, might also be a potential marker for identifying patients with high cardiovascular risk. This study aimed to compare OPG levels, FMD, and CIMT measurements in subjects with vs. without diabetes and investigate the association of serum osteoprotegerin level with the early atherosclerotic markers, endothelial function, and carotid intima-media thickness (CIMT) in patients with type 2 diabetes mellitus (DM2). METHODS: Forty-nine patients with DM2 (F/M: 26/23, 49.3 ± 10.0 years) and 45 healthy volunteers (F/M: 26/19, 48.3 ± 7.5 years) were included in this cross-sectional study. Serum OPG levels were measured by solid-phase enzyme-linked immunosorbent assay (ELISA). Fasting plasma glucose (FPG) and HbA1c levels were measured. CIMT was measured by B-mode ultrasound, and endothelial function was evaluated via flow-mediated dilation (FMD) of the brachial artery with Doppler ultrasonography. RESULTS: Serum OPG levels were significantly higher in patients with DM2 (617.0 ± 111.0 pg/mL) compared to controls (481.0 ± 96.0 pg/mL, p < 0.001). While CIMT in diabetic patients (0.65 + 0.13 mm) was higher than controls (0.54 ± 0.10 mm, p = 0.009), FMD measurement was lower in DM2 group (4.2% ± 3.1 mm vs. 7.6% ± 4.1 mm, p = 0.01). Univariate analysis showed that OPG was associated with the presence of diabetes (OR: 6.999, p = 0.001, R2: 15.1%) and hypertension (OR = 6.925, p = 0.001, R2: 13.2%). There was no relationship between OPG levels and CIMT or FMD. CONCLUSION: Osteoprotegerin and CIMT levels were increased, and FMD measurements were decreased in patients with DM2. No association between CIMT, FMD, and OPG measurements was observed. The presence of DM and hypertension were associated with circulating OPG levels.

The Association of Thyroid Hormone Changes with Inflammatory Status and Prognosis in COVID-19.

BACKGROUND: COVID-19 infection may have multiorgan effects in addition to effects on the lungs and immune system. Recently, studies have found thyroid function abnormalities in COVID-19 cases which were interpreted as euthyroid sick syndrome (ESS) or destructive thyroiditis. Therefore, in this study, we aimed to evaluate the thyroid function status and thyroid autoimmunity in COVID-19 patients. Material and Method. 205 patients were included. The medical history and laboratory parameters at admission were collected from medical records. Serum thyroid-stimulating hormone (TSH), free thyroxine (FT4), free triiodothyronine (FT3), thyroid peroxidase antibody, and thyroglobulin antibody were measured, and patients were classified according to thyroid function status. RESULTS: 34.1% of the patients were euthyroid. Length of hospitalization (p < 0.001), rate of oxygen demand (p < 0.001), and intensive care unit (ICU) admission (p=0.022) were lower, and none of the euthyroid patients died. 108 (52.6%) patients were classified to have ESS, 57 were classified as mild, and 51 were moderate. The inflammatory parameters were higher in patients with moderate ESS. In cluster analysis, a high-risk group with a lower median FT3 value (median = 2.34 ng/L; IQR = 0.86), a higher median FT4 value (median = 1.04 ng/dL; IQR = 0.33), and a lower median TSH value (median = 0.62 mIU/L; IQR = 0.59) included 8 of 9 died patients and 25 of the 31 patients that were admitted to ICU. Discussion. Length of hospitalization, oxygen demand, ICU admission, and mortality were lower in euthyroid patients. Moreover, none of the euthyroid patients died. In conclusion, evaluation of thyroid function tests during COVID-19 infection may give information about the prognosis of disease.

Clinical and Hormonal Profiles Correlate With Molecular Characteristics in Patients With 11ß-Hydroxylase Deficiency.

BACKGROUND: Given the rarity of 11ß-hydroxylase deficiency (11ßOHD), there is a paucity of data about the differences in clinical and biochemical characteristics of classic (C-11ßOHD) and nonclassic 11ßOHD (NC-11ßOHD). OBJECTIVE: To characterize a multicenter pediatric cohort with 11ßOHD. METHOD: The clinical and biochemical characteristics were retrospectively retrieved. CYP11B1 gene sequencing was performed. Seventeen plasma steroids were quantified by liquid chromatography-mass spectrometry and compared to that of controls. RESULTS: 102 patients (C-11ßOHD, n = 92; NC-11ßOHD, n = 10) from 76 families (46,XX; n = 53) had biallelic CYP11B1 mutations (novel 9 out of 30). Five 46,XX patients (10%) were raised as males. Nineteen patients (19%) had initially been misdiagnosed with 21-hydroxylase deficiency. Female adult height was 152 cm [-1.85 SD score (SDS)] and male 160.4 cm (-2.56 SDS).None of the NC-11ßOHD girls had ambiguous genitalia (C-11ßOHD 100%), and none of the NC-11ßOHD patients were hypertensive (C-11ßOHD 50%). Compared to NC-11ßOHD, C-11ßOHD patients were diagnosed earlier (1.33 vs 6.9 years; P < 0.0001), had higher bone age-to-chronological age (P = 0.04) and lower adult height (-2.46 vs -1.32 SDS; P = 0.05). The concentrations of 11-oxygenated androgens and 21-deoxycortisol were low in all patients. The baseline ACTH and stimulated cortisol were normal in NC-11ßOHD. Baseline cortisol; cortisone; 11-deoxycortisol; 11-deoxycorticosterone and corticosterone concentrations; and 11-deoxycortisol/cortisol, 11-deoxycorticosterone/cortisol, and androstenedione/cortisol ratios were higher in C-11ßOHD than NC-11ßOHD patients (P < 0.05). The 11-deoxycortisol/cortisol ratio >2.2, <1.5, and <0.1 had 100% specificity to segregate C-11ßOHD, NC-11ßOHD, and control groups. CONCLUSION: NC-11ßOHD can escape from clinical attention due to relatively mild clinical presentation. However, steroid profiles enable the diagnosis, differential diagnosis, and subtyping of 11ßOHD.

Reference values for T and B lymphocyte subpopulations in Turkish children and adults

Background/aim: Established reference values are critical for the interpretation of immunologic assessments. In particular, the proportion and absolute counts of T- and B- cell subpopulations are subject to change with age and ethnicity. We aimed to establish age- specific reference values for lymphocyte subsets using updated immunophenotyping panels. Materials and methods: We studied a total of 297 healthy Turkish subjects aged 0 to 50 years, stratified into major age brackets in a cluster factor of 10 per age-group. The predetermined age intervals contained randomly allocated participants enrolled over a period of 6 months, who were homogenously distributed by sex. We analyzed a complete blood count test and simultaneously with detailed immunophenotyping enumerated the percent and absolute cell counts of lymphocyte subsets. Results: The percentage and absolute counts of lymphocyte subsets show a marked surge across the age-span. T helper, T cytotoxic, and the natural killer cell numbers were increasing from birth until 6 months, followed by a gradual decrease thereafter. B cell numbers were rising until 2 years, followed by a gradual decrease for the upcoming years, accompanied by a steady expansion of unclass-switched- and class-switched- B cells. Conclusion: We provide updated extensive reference intervals for lymphocyte subpopulations in Turkish people.

Evaluation of Arterial Functions and Carotid Intima Media Thickness in Children During Mid-Term Follow-Up After Kawasaki Disease.

OBJECTIVE: Kawasaki disease (KD) is a multisystemic vasculitis of medium- and small-sized arteries. The involvement of the coronary arteries may lead to long-term cardiovascular sequelae. We studied the elasticity of the aorta and the common carotid artery (CCA), flowmediated dilatation of the brachial artery, and carotid intima media thickness, as well biomarkers such as high-sensitivity C-reactive protein (hs-CRP) and elastin, as useful indicators of cardiovascular risk in patients, following KD. METHODS: The study group consisted of 26 patients with a history of KD, and 26 healthy children. Echocardiography, and carotid and brachial ultrasound studies were performed. Plasma hs- CRP and elastin levels were studied in both groups. RESULTS: The stiffness indices (SI) obtained from the aortic arch, abdominal aorta, and the CCA were increased in the patients, compared to the controls. Distensibility was decreased at the sinus of Valsalva, the sinotubular junction, the aortic arch, and the ascending aorta, compared to the control group. Flow-mediated dilatation (FMD) was lower in the patients than in the controls. The age of the patients had a negative correlation to distensibility of the aortic arch and abdominal aorta, and a positive correlation to the stiffness of the aortic arch. Follow-up duration correlated positively to stiffness of the aortic arch. Carotid intima-media thickness (CIMT), serum hs-CRP, and elastin levels did not differ between the groups. CONCLUSION: Increased aortic and carotid stiffness and decreased aortic distensibility suggest impaired arterial functions following KD. Long-term follow-up and monitorization early in cardiovascular disease is needed.