Trough anti-Xa activity after intermediate dose nadroparin for thrombosis prophylaxis in critically ill patients with COVID-19 and acute kidney injury.

Our objective was to assess the incidence of drug bioaccumulation in critically ill COVID-19 patients with AKI receiving intermediate dose nadroparin for thrombosis prophylaxis. We conducted a Prospective cohort study of critically ill COVID-19 patients. In patients on intermediate dose nadroparin (5700 IU once daily) we assessed the incidence of bioaccumulation (trough anti-Xa level > 0.2 IU/mL) stratified according to presence of AKI. We quantified this association using multilevel analyses. To assess robustness of our observations, we explored the association between AKI and anti-Xa activity in patients receiving high dose nadroparin (> 5700 IU). 108 patients received intermediate dose nadroparin, of whom 24 had AKI during 36 anti-Xa measurements. One patient with AKI (4.2% [95%CI 0.1-21%]) and 1 without (1.2% [95%CI 0.03-6.5%]) developed bioaccumulation (p = 0.39). Development of AKI was associated with a mean increase of 0.04 (95%CI 0.02-0.05) IU/ml anti-Xa activity. There was no statistically significant association between anti-Xa activity and AKI in 51 patients on high dose nadroparin. There were four major bleeding events, all in patients on high dose nadroparin. In conclusion, Bioaccumulation of an intermediate dose nadroparin did not occur to a significant extent in critically ill patients with COVID-19 complicated by AKI. Dose adjustment in AKI may be unnecessary.

Accurate and fast diagnostic algorithm for febrile urinary tract infections in humans.

BACKGROUND: The urine dipstick that detects nitrite and leukocyte esterase, and urine sediment is commonly used to diagnose or exclude urinary tract infections (UTIs) as the source of infection in febrile patients admitted to the emergency department of Dutch hospitals. However, the diagnostic accuracy of the urine dipstick and urine sediment has never been studied in this specific situation. METHODS: Urinary samples of 104 febrile consecutive patients were examined. Urine culture with ≥ 10(5) colonies/ml of one or two known uropathogen was used as the gold standard. The diagnostic value of the urine dipstick, urine sediment and Gram stain at various cut-off points was determined and used to develop a new diagnostic algorithm. This algorithm was validated in a new group of sepsis patients based on systemic inflammatory response syndrome (SIRS) criteria. RESULTS: A positive nitrite on the urine dipstick (specificity 99%) rules in UTI. This is the first step of our diagnostic algorithm. The second step is to exclude UTI by absence of bacteria in the urine sediment (sensitivity 94%). The third and last step is the number of leucocytes/high-power field (hpf) in the urine sediment. Less than 10 leucocytes/hpf makes UTI unlikely whereas ≥ 10 leucocytes/hpf indicates UTI. In contrast to urine dipstick and/or urine sediment results alone, our algorithm showed both a high sensitivity (92%) and specificity (92%) and was validated in a new sepsis population. CONCLUSION: Our accurate and fast diagnostic algorithm, which combines the selective results of urine dipstick and urine sediment, can be easily used to diagnose UTI in febrile patients at the emergency department of Dutch hospitals.

Salivary cortisol as an alternative for serum cortisol in the low-dose adrenocorticotropic hormone stimulation test?

BACKGROUND: Salivary cortisol is unaffected by cortisol binding globulin and reflects free serum cortisol as compared to total serum cortisol. AIM: The aim of the present study was to compare the salivary cortisol response with the serum cortisol response in a low-dose (1-microg) ACTH test in a clinical setting and to determine the optimal cut-off value of salivary cortisol as an alternative to serum cortisol. MATERIAL/SUBJECTS AND METHODS: We measured serum and salivary cortisol responses to iv administration of 1-microg ACTH in 51 patients (17 males) referred to the Department of Clinical Chemistry for ACTH-testing. Serum cortisol was assessed before, 20, and 30 min after ACTH-administration, and salivary cortisol was assessed before and 30 min after ACTH administration. RESULTS: Mean cortisol at baseline, 20, and 30 min were 0.44 micromol/l (SD: 0.22), 0.64 micromol/l (SD: 0.24), and 0.70 micromol/l (SD: 0.25), respectively. Median basal salivary cortisol was 8.4 nmol/l [interquartile range (IQR): 3.8-14.2]. Salivary cortisol at 30 min equaled 35.9 nmol/l (IQR: 21.1-46.2). Basal salivary cortisol was significantly correlated with salivary cortisol at 30 min (r=0.53; p<0.001). Salivary cortisol at 30 min of 23.5 nmol/l had a sensitivity and specificity of 78.1% and 70.0%, respectively as compared to the serum cortisol cut-off values of >0.50 micromol/l. CONCLUSIONS: The salivary low-dose ACTH-test yields more dynamic responses than serum cortisol. However, the sensitivity and specificity of salivary cortisol are too low to be adequate as an alternative to the serum cortisol measurements. In women on estrogen therapy, however, the use of salivary cortisol might be superior to serum cortisol.

The effect of clinical characteristics on the lecithin/sphingomyelin ratio and lamellar body count: a cross-sectional study.

OBJECTIVES: To study the changes in the lecithin/sphingomyelin (L/S) ratio and lamellar body count (LBC) during pregnancy and to study the effect of clinical characteristics on these measurements. METHODS: We reviewed in retrospect the amniotic fluid samples for the assessment of fetal lung maturity of consecutive women between January 1996 and December 2000. We evaluated the effect of antenatal administration of glucocorticoids, the presence of diabetes, fetal growth restriction and the amount of amniotic fluid on the L/S ratio and LBC. We then constructed normal curves, by relating the L/S ratio and LBC to gestational age in the cases without respiratory distress syndrome (RDS). Data from the literature were added to these curves. RESULTS: From the 334 included women, 64 infants (19%) developed RDS. The LBC was lower in women with polyhydramnios (p = 0.04), and similar in women with oligohydramnios. Administration of glucocorticoids, the presence of maternal diabetes or fetal growth restriction did not affect the L/S ratio or the LBC. The median L/S ratio in cases without RDS showed a constant increase from a gestational age of 28 weeks onwards. The median LBC increased slowly between a gestational age of 28 weeks and 34 weeks, to increase more steeply thereafter. CONCLUSIONS: The amount of amniotic fluid affects the LBC, but not the L/S ratio. Since the L/S ratio and the LBC increase with gestation, differences in gestational age should be taken into account in the interpretation of these fetal lung maturity tests.