Towards clinical adherence monitoring of oral endocrine breast cancer therapies by LC-HRMS-method development, validation, comparison of four sample matrices, and proof of concept.

Oral endocrine therapies (OET) for breast cancer treatment need to be taken over a long period of time and are associated with considerable side effects. Therefore, adherence to OET is an important issue and of high clinical significance for breast cancer patients' caregivers. We hypothesized that a new bioanalytical strategy based on liquid chromatography and high-resolution mass spectrometry might be suitable for unbiased adherence monitoring (AM) of OET. Four different biomatrices (plasma, urine, finger prick blood by volumetric absorptive microsampling (VAMS), oral fluid (OF)) were evaluated regarding their suitability for AM of the OET abemaciclib, anastrozole, exemestane, letrozole, palbociclib, ribociclib, tamoxifen, and endoxifen. An analytical method was developed and validated according to international recommendations. The analytical procedures were successfully validated in all sample matrices for most analytes, even meeting requirements for therapeutic drug monitoring. Chromatographic separation of analytes was achieved in less than 10 min and limits of quantification ranged from 1 to 1000 ng/mL. The analysis of 25 matching patient samples showed that AM of OET is possible using all four matrices with the exception of, e.g., letrozole and exemestane in OF. We were able to show that unbiased bioanalytical AM of OET was possible using different biomatrices with distinct restrictions. Sample collection of VAMS was difficult in most cases due to circulatory restraints and peripheral neuropathy in fingers and OF sampling was hampered by dry mouth syndrome in some cases. Although parent compounds could be detected in most of the urine samples, metabolites should be included when analyzing urine or OF. Plasma is currently the most suitable matrix due to available reference concentrations.

Birth weight, Apgar scores and gentamicin were associated with acute kidney injuries in VLBW neonates requiring treatment for patent ductus arteriosus.

AIM: We assessed the risk factors for transient acute kidney injury in very low birth weight (VLBW) infants treated for patent ductus arteriosus (PDA) using the serum creatinine-based criteria in Kidney Disease: Improving Global Outcomes. METHOD: This retrospective study of infants requiring ibuprofen and, or, surgery for haemodynamic relevant PDAs was performed at the University Children's Hospital of Saarland, Homburg, Germany, from January 2009 to December 2015. RESULTS: We studied 422 infants with a mean birth weight of 1059 ± 308.2 g. Acute kidney injuries developed in 150/295 infants (50.9%) with spontaneous PDA closure, in 46/82 (56.1%) who received intravenous ibuprofen treatment, in 18/24 (75.0%) who had surgery and in 15/21 infants (71.4%) who received both medical and surgical treatment. Acute kidney injuries were associated with birth weight and gestational age, Apgar scores at 10 minutes, the PDA size corrected for birth weight, a PDA with three affected circulatory territories, PDA surgery and gentamicin. Multiple logistic regression analysis showed particular associations between acute kidney injury and birth weight (p = 0.001), the 10-minute Apgar score (p = 0.02) and gentamicin (p = 0.043). CONCLUSION: Birth weight, the 10-minute Apgar score and gentamicin were particularly associated with acute kidney injuries in our cohort.

Nucleated red blood cells and serum lactate values on days 2 and 5 are associated with mortality and morbidity in VLBW infants.

AIM: To correlate nucleated red blood cell counts and serum lactate concentrations on day 2 and 5 of life with morbidity and mortality in very low birth weight infants and to determine corresponding cutoff values. METHODS: Retrospective analysis in a cohort of very low birth weight infants. RESULTS: 250 very low birth weight infants were included in this study. Gestational age ranged from 23 to 35 weeks (mean 29.04) and birth weight was 320-1500 g (mean 1047.9). 55 (22%) patients developed intraventricular hemorrhage, 55 (22%) bronchopulmonary dysplasia, 12 (4.8%) periventricular leukomalacia, 93 (37.2%) retinopathy of prematurity, and 1 (0.4%) necrotizing enterocolitis. Mortality rate was 25/250 (10%). Nucleated red blood cells and serum lactate on day 2 of life were associated with mortality (p < 0.001). Serum lactate on day 5 of life demonstrated an association with retinopathy of prematurity (p = 0.017), bronchopulmonary dysplasia (p = 0.044), and intraventricular hemorrhage (p < 0.001). Cutoff values predicting mortality were >89.5 nucleated red blood cells/100 leucocytes (sensitivity 68.2%, specificity 89.0%) and serum lactate concentrations >8.5 mmol/l (sensitivity 69.6%, specificity 93.5%) on day 2 of life. CONCLUSION: We conclude that both nucleated red blood cell count and serum lactate concentration are valuable biomarkers in predicting important outcome parameters in very low birth weight infants.

Reference values for nucleated red blood cells and serum lactate in very and extremely low birth weight infants in the first week of life.

STUDY PURPOSE: To provide reference values for nucleated red blood cells and serum lactate concentrations in very and extremely low birth weight (VLBW/ELBW) infants in the first week of life. PATIENTS AND METHODS: Retrospective data analysis of serial, daily measurements of NRBC counts and serum lactate during the first 6days of life in VLBW and ELBW infants. RESULTS: In total, 250 infants<1500g were included in this study. Intrauterine growth retardation (IUGR) was seen in 87 (34.8%) patients. Gestational age (GA) ranged from 23 to 35weeks (mean 29.0weeks) and birth weight (BW) was 320-1499g (mean 1047.9g). During hospital stay, 55 (22%) patients developed IVH and 55 children (22%) BPD. PVL was seen in 12 (4.8%) cases, ROP in 93 (37.2%) and NEC in only 1 (0.4%) patient. NRBC counts as well as serum lactate concentrations depended significantly on birth weight (p<0.01) and presence respectively absence of IUGR (p<0.01). Both NRBC counts and serum lactate concentrations declined constantly during the 6-day period (p<0.01), and both were highly inter-correlated (p<0.01). CONCLUSIONS: This is one of only a very few studies that systematically and serially evaluated both NRBC counts and serum lactate concentration in VLBW and ELBW infants in the first 6days of life. Both parameters were significantly dependent on birth weight and the presence of IUGR. Moreover, a significant correlation between NRBC counts and serum lactate concentrations in this early period of life could be demonstrated. In future studies, the role of these readily available biomarkers in predicting important neonatal outcome parameters needs to be evaluated in a prospective manner.