Pretransplant renal function according to CKD-EPI cystatin C equation is a prognostic factor of death after liver transplantation

International audienceBackground & aims - In patients with cirrhosis, cystatin C (CystC) based equations may be more accurate indicators of glomerular filtration rate (GFR) than creatinine (Pcr) based equations. Renal function before liver transplantation (LT) is thought to impact survival after LT. We aimed at assessing pretransplant creatinine and CystC based equations with respect to their predictive value on long-term survival after LT. Methods - From 2001 to 2011, CystC was determined at pre-LT evaluation in 682 patients together with GFR assessed using MDRD-4, MDRD-6, CKD-EPI-cystatin C, CKD-EPI-creatinine and CKD-EPI-creatinine-cystatin C equations. Patients were classified according to the Kidney Disease Outcomes Quality Initiative classification (KDOQI). Results - Median age at LT was 55 [49-60] years with a median MELD score of 13.5 [8.3-19.2] and a median post-transplant follow-up of 60 [26-89] months. Using CKD-EPI Cystatin C and the KDOQI classification, 21.1% of patients were stage 1, 43.1% stage 2, 29.1% stage 3 and 6.5% stage 4. Kaplan-Meier survival estimates were significantly different between KDOQI stages when determined using the CKD-EPI-CystatinC equation. This was not the case when using the other equations. At multivariate analysis, GFR and KDOQI estimated using the CKD-EPI-CystatinC equation were significantly associated with death (HR: 0.992; CI95%: 0.986-0.999 and 1.24; CI95%: 1.02-1.50 respectively). When assessed using the MDRD-4, MDRD-6, CKD-EPI-Creatinine-CystatinC and CKD-EPI-Creatinine equations GFR was not significantly associated with death. Conclusions - Estimated pre-LT renal function is predictive of post-LT survival only when assessed using the CKD-EPI cystatin C equation. This supports the use of Cystatine C and of its related equation for the assessment of renal function before liver transplantation

Daratumumab: Therapeutic asset, biological trap!

OBJECTIVES : Recently, daratumumab has been included in the therapeutic strategies for myeloma patients. This molecule is an antibody directed against CD38, strongly expressed on plasma cells. Nevertheless, as CD38 is also present on erythrocyte membrane, daratumumab interferes with immunohaematological tests, complicating the selection of compatible blood. METHODS : A total of 14 patients treated by daratumumab have been followed in our transfusion laboratory. Among them, 11 have been transfused. Dithiotreitol (DTT) has been used to inhibit the daratumumab's interference, in the pre-transfusion tests (irregular antibody screening and cross-match). RESULTS : The red blood cell treatment with DTT has been very efficacious to inhibit the daratumumab's interference in 13 patients out of 14. Some precautionary measures had to be taken into account, especially the pH and the storage conditions. An extended pheno/genotype was an additional security element in the selection of compatible blood. To simplify and to optimize the laboratory practices, a decisional flow chart has been written. CONCLUSION : DTT red blood cell treatment is very useful and efficacious in the pre-transfusion tests of patients treated with daratumumab. It allows to avoid the selection of blood bags only on the basis of an extended pheno/genotype, what is more secure and more ethical with respect to other at higher risk patients. A clear decisional flow chart allows a quality assurance gait. Collaboration with physicians is essential.[Daratumumab : joker thérapeutique, piège biologique !] OBJECTIFS : Récemment, le daratumumab a intégré l’arsenal thérapeutique du myélome. Il est dirigé contre la molécule CD38, fortement exprimée sur les plasmocytes. Comme CD38 est également présent à la surface des globules rouges, le traitement par daratumumab induit des interférences dans les tests immunohématologiques, compliquant le choix des poches de sang à transfuser. METHODES : Au total, 14 patients traités par daratumumab ont été suivis dans notre laboratoire de transfusion. Onze d’entre eux ont bénéficié d’une transfusion. Un traitement des globules rouges par le dithiotréitol (DTT) a été utilisé afin de contrecarrer l’interférence par l’anticorps anti-CD38, pour les tests de recherche d’anticorps irréguliers et pour les tests de compatibilité. RESULTATS : Moyennant le respect de quelques mesures de précaution, en particulier le respect du pH et des conditions de conservation, le traitement des hématies par le DTT a permis d’annihiler efficacement l’interférence du daratumumab chez 13 patients sur 14. Un phénotype ou génotype complet des patients avant traitement par daratumumab a apporté une sécurité supplémentaire pour le choix des poches à transfuser. Afin de simplifier et d’homogénéiser les pratiques au laboratoire, un logigramme décisionnel de prise en charge a été rédigé. CONCLUSION : L’utilisation du DTT dans les tests immunohématologiques des patients traités par daratumumab est très efficace. Ceci permet d’éviter la sélection des poches à transfuser sur la seule base du respect du phéno/génotype étendu, ce qui nous semble une démarche plus sûre sur le plan transfusionnel et plus éthique vis-à-vis des autres patients à plus haut risque transfusionnel. Un logigramme décisionnel clair permet une démarche de qualité. La collaboration avec les cliniciens est indispensable

Determinants of apnea-hypopnea index variability during home sleep testing.

A single-night attended in-laboratory polysomnography or home sleep testing are common approaches for obstructive sleep apnea (OSA) diagnosis. However, internight variability in apnea-hypopnea index value is common, and may result in misclassification of OSA severity and inapropriate treatment decisions. To investigate factors determining short-term apnea-hypopnea index variability using multi-night automated home sleep testing, and to determine how this variability impacts clinical decisions. Adults with suspected OSA who successfully performed three home sleep tests using measurements of mandibular jaw movements (Sunrise, Namur, Belgium) combined with automated machine learning analysis were enrolled. Data analysis included principal component analysis, generalized estimating equation regression and qualitative agreement analysis. 160 individuals who performed three sleep tests over a mean of 8.78 ± 8.48 days were included. The apnea-hypopnea index varied by -0.88 events/h (5th-95th percentile range: -14.33 to 9.72 events/h). Based on a single-night recording, rates of overtreatment and undertreatment would have been of 13.5% and 6.0%, respectively. Regression analysis adjusted for age, sex, body mass index, total sleep time, and time between home sleep tests showed that time spent in deep non-rapid eye movement sleep and with head in supine position were independent significant predictors of the apnea-hypopnea index variability. At the individual level, short-term internight variability in the apnea-hypopnea index was significantly associated with time spent in deep non-rapid eye movement sleep and head in supine position. Clinical decisions based on a single-night testing may lead to errors in OSA severity classification and incorrect therapeutic decisions