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Reference intervals (RIs) for laboratory analyses by and large, are provided by analytical platform providers – the provenience and preanalytics of materials for the calculation of intervals often remain arcane particularly relating to the age group of donors. In an observational, prospective cohort study on 1467 healthy uniracial Caucasian residents >60 years of age, 105 frequently used lab tests were done on one blood sample. With a nonrestrictive definition of health, several pathological lab results pointing to occult disease have been found and published from SENIORLAB so far. The RIs found for hemoglobin in women went from 117.9 to 152.4 g/L (80–84 years) and in men from 124.9 to 170.6 g/L (90% confidence interval [CI]). This article lists RIs computed with SENIORLAB data for such frequently ordered analyses as platelet counts, vitamin B12 and folate, ferritin and analytes measured to estimate metabolic performance in glucose turnover. In fact, 64.5% of the cohort showed prediabetic fasting plasma glucose (FPG) and/or glycated hemoglobin (HbA 1c ); total serum folate levels but not red blood cell folate decreased with progressing age. As much as 66% of evaluable study participants had insufficient levels of 25(OH) vitamin D. Published reports from SENIORLAB are referenced in this article.

Although recent evidence seems to suggest a steady or even declining prevalence and incidence of dementias, these disorders pose a tremendous threat to health care and caregivers. The most common, dominant cause of dementia is Alzheimer’s disease (AD) followed by Levy body dementia (LBD) and vascular dementia (VD). Over the last 25 years, great progress has been made in understanding the pathogenesis of AD but not yet in its treatment. Advancements have been made by ever improving clinical and paraclinical definitions allowing for a continuously increasing differentiation of the various causes of dementias. Besides imaging, functional imaging using positron emission tomography (PET) is now being increasingly used to define the amyloid load in vivo in the brain. By the use of tau-specific tracers meaningful tau imaging may be achieved in the future. The discovery of the cleaving mechanisms of the amyloid precursor protein (APP) and the identification of its major products such as Aβ 1−42 and Aβ 1−40 as well the metabolism of tau and its phosphorylation have provided reasonably reliable markers to evaluate their usefulness for the diagnosis of AD, LBD, frontotemporal dementia (FTD), Parkinson’s disease (PD), alcohol-related dementia (ARD), traumatic brain injury (TBI), mixed dementia (MD) and others first by cerebrospinal fluid (CSF) analysis and now, due to the introduction of a digital single molecule array (Simoa), by plasma testing. This promising new technique should open avenues for the laboratory validation of other markers such as neurofilament light chains (NfL), visinin-like protein-1 (VLP-1), heart fatty acid binding protein (HFABP) and YKL-40, facilitating further differentiation of the various forms of dementia thus leading to improved treatment.

Background Data on peripheral blood cell values in older subjects are rare. While hemoglobin (Hb) values are supposed to change with rising age, little is known about reference values for other erythrocytic blood cell counts. This cross-sectional study was initiated to analyze hematologic laboratory parameters among subjects aged ≥60 years. Methods This was a retrospective cross-sectional study of outpatient laboratory data between January 1 st and December 31 st , 2015 originating from a German countrywide laboratory group; inclusion criteria: age ≥60 years, normal C-reactive protein (CRP), transferrin saturation, reticulocytes, lactate dehydrogenase, haptoglobin and soluble transferrin receptor; exclusion criteria: glomerular filtration rate (GFR)<60 mL/min, lack of inclusion criteria; primary objective: assessment of the mean Hb value; secondary objective: assessment of mean values of red blood cell (RBC) counts. Results Of 30,611 subjects ≥60 years, 4641 met the inclusion criteria and were thus considered hematologically healthy; the following age groups were formed: 60–69 years (2094), 70–79 years (2171), 80–89 years (360), >90 years (16); median values for male/female subjects were: Hb 15.2/14.0 g/dL, RBC 5.0/4.6/μL, mean cellular volume (MCV) 89/89/fl, mean corpuscular hemoglobin (MCH) 31/30 pg/RBC, mean corpuscular hemoglobin concentration (MCHC) 34/34 g/dL, hematocrit (hct) 44/41%. Statistical evaluation revealed a slight but significant decrease in values over age decades for all parameters except for MCH. However, all values remained within the recommended German Society of Hematology and Oncology (DGHO) reference ranges. Hb values remained above the recommended World Health Organization (WHO) cut-offs for definition of anemia. Conclusions The results confirm the WHO reference values and are in accordance with the recommended DGHO reference values and previous results of other study cohorts outside Germany. There seems to be no need for establishing age-specific RBC or erythrocytic reference ranges for subjects >60 years.

Background It has been demonstrated that vitamin B12 determinations fail, especially in patients with pernicious anemia with high titers of intrinsic factor antibody. Consistent with this finding, we observed a case of falsely normal holotranscobalamin (HoloTC) results in a patient with pernicious anemia and severe vitamin B12 deficiency. We aimed to investigate whether such a situation can also be seen in other individuals. Methods Within the frameworks of the SENIORLAB study and routine samples from a mixed patient population referred to a laboratory for investigation of B12 status, we searched for study participants displaying a normal HoloTC level (≥50 pmol/L) together with a decreased total vitamin B12 level (<125 pmol/L). Thereafter, we determined whether samples with discrepant biochemical markers (i.e. low vitamin B12, normal HoloTC) also had increased functional markers of vitamin B12 deficiency (methyl malonic acid [MMA], homocysteine [Hcy]) and/or a low value of Fedosov’s combined indicator of vitamin B12 status (<−0.5). Results The prevalence of a normal HoloTC level and low total vitamin B12 level among the group of healthy seniors (n=1451) was 0.21% (95% confidence interval [CI], CI, 0.08–0.6%). Among the 106,635 routine samples with concurrent HoloTC and total vitamin B12 determination, 176 (i.e. 0.17%, 95% CI, 0.14–0.19%) had discrepant biochemical markers. Among them, 24 who were identified as having discrepant biochemical markers and a diagnosis of vitamin B12 deficiency could be confirmed with functional markers. Conclusions Initial and isolated screening for vitamin B12 deficiency using a HoloTC cut-off of ≥50 pmol/L in a small subset of patients may reveal false-negative (normal) results, meaning that patients with vitamin B12 deficiency may remain undetected.

Background Vitamin D affects glucose metabolism by increasing insulin secretion and insulin receptor expression. Also, it exerts these effects by binding to its primary receptor, the vitamin D receptor (VDR). In this preliminary study, we aimed to examine serum 25-(OH) vitamin D 3 and serum VDR levels in gestational diabetes mellitus (GDM) patients. Methods Blood samples were obtained during 24–28 weeks of pregnancy from patients with GDM (n=30) and age, body mass index (BMI), and gestational age-matched control subjects (n=33). Both groups were examined for changes in the levels of glucose, insulin, glycated hemoglobin (bA 1c ), 25-(OH) vitamin D 3 and VDR. Results There were no significant differences in serum 25-(OH) vitamin D 3 and fasting insulin levels between the control and GDM groups (p=0.115, p=0.182). But serum VDR levels were significantly higher in the GDM group than in the control group (p=0.001). Conclusions Although there was no significant difference between the two groups regarding 25-(OH) vitamin D 3 levels, it is notable that VDR levels were higher in GDM patients. To further define the role of vitamin D in the prophylaxis and treatment of GDM, it may be useful to conduct more extensive studies on VDR.

Background Virulence factors of Helicobacter pylori including cagA , vacA , iceA and their association with clinical manifestation varied widely with different subpopulations. The objective of the study was to determine the prevalence of cagA , iceA1 , iceA2, vacA , vacA s1/s2 , vacA m1/m2 , Western type cagA and East Asian type cagA virulence genes in H. pylori isolated from gastric ulcer patients and evaluate the association of these genes with gender, age, smoking and alcohol consumption. Methods Gastric biopsy samples from 172 patients were collected. H. pylori virulence genes, cagA , vacA , iceA1 , iceA2 , vacA s1/s2 , vacA m1/m2 , Western type cagA and East Asian type cagA were detected using polymerase chain reaction (PCR). Results Of the gastric biopsy samples collected, 48.3% of samples grew H. pylori. The vacA (68.7%) was the predominant virulence gene detected and associated with male patients and patients within the age group of 31–40 years. The cagA was the second most common gene detected and significantly associated with alcoholic patients. Conclusions H. pylori infection rate was 48.3% and was associated with patients who were smokers or had a history of smoking. The majority of our isolates were positive for any one of the virulence genes tested indicating that these isolates were highly virulent in nature.