Search

Little is known about the effect tubulointerstitial nephropathies have in modulating maternal-fetal outcomes in pregnancy. Therefore, we analyzed the main outcomes of pregnancy in these women to gain a better understanding of the role of a reduction in maternal kidney mass. From the Torino Cagliari Observational Study (TOCOS) cohort, we selected 529 patients with a diagnosis of tubulointerstitial disease and focused on 421 patients with chronic kidney disease (CKD) stage 1, without hypertension but with proteinuria less than 0.5 g/day at referral. From a cohort of 2969 singleton deliveries from low-risk pregnancies followed in the same settings we selected a propensity score matched control cohort of 842 pregnancies match 2:1 for age, parity, body mass index, ethnicity, and origin. Time to delivery was significantly shorter in the study cohort 38.0 (Quartile 1-Quartile 3: 37.0-39.0) versus 39.0 (Q1-Q3 38.0-40.0) weeks, with respect to controls. Incidence of delivery of less than 37 gestational weeks significantly increased from controls (7.4%) to women with previous acute pyelonephritis (10.8%), other tubulointerstitial diseases (9.7%) and was the highest in patients with a single kidney (31.1%). Similarly, neonatal birthweight significantly and progressively decreased from controls (3260 g [Q1-Q3: 2980-3530]), previous acute pyelonephritis (3090 g [Q1-Q3: 2868-3405], other tubulointerstitial diseases (3110 g [Q1-Q3: 2840-3417]), and to solitary kidney (2910 g [Q1-Q3: 2480-3240]). Risk of developing preeclampsia was significantly higher in the CKD cohort (3.6% vs 1.7% in low-risk controls). Thus, even a small reduction in functional kidney mass, such as a pyelonephritic scar, is associated with a shorter duration of pregnancy and an increased risk of preterm delivery. The risk is proportional to the extent of parenchymal reduction and is highest in cases with a solitary kidney.

Chronic kidney disease (CKD) induces muscle wasting and a reduction in the maximum voluntary force (MVF). Little is known about the neuromuscular fatigability in CKD patients, defined as the reduction of muscle force capacities during exercise. Neuromuscular fatigability is a crucial physical parameter of the daily living. The quantification of explosive force has been shown to be a sensitive means to assess neuromuscular fatigability. Thus, our study used explosive force estimates to assess neuromuscular fatigability in elderly CKD patients. Inclusion criteria for CKD patients were age ≥ 60 years old and glomerular filtration rate (GFR) < 45 mL/min/1.73 m2not on dialysis, and those for controls were GFR > 60 mL/min/1.73 m2, age and diabetes matched. The fatigability protocol focused on a handgrip task coupled with surface electromyography (sEMG). Scalars were extracted from the rate of force development (RFD): absolute and normalized time periods (50, 75, 100, 150 and 200 ms, RFD50, RFD75, RFD100, RFD150and RFD200, respectively), peak RFD (RFDpeakin absolute; NRFDpeaknormalized), time‐to‐peak RFD (t‐RFDpeak) and the relative force at RFDpeak(MVF‐RFDpeak). A statistical parametric mapping approach was performed on the force, impulse and RFD–time curves. The integrated sEMG with time at 0–30, 0–50, 0–100 and 0–200 ms time intervals relative to onset of sEMG activity was extracted and groups were compared separately for each sex. The cohort of 159 individuals had a median age of 69 (9IQR) years and body mass index was 27.6 (6.2IQR) kg/m2. Propensity‐score‐matched groups balanced CKD patients and controls by gender with 66 males and 34 females. In scalar analysis, CKD patients manifested a higher decrement than controls in the early phase of contraction, regarding the NRFDpeak(P= 0.009; η2p= 0.034) and RFD75and RFD100(for both P< 0.001; η2p= 0.068 and 0.064). The one‐dimensional analysis confirmed that CKD males manifest higher and delayed neuromuscular fatigability, especially before 100 ms from onset of contraction. sEMG was lower in CKD patients than controls in the 0–100 ms (at rest: P= 0.049, Cohen's d= 0.458) and 0–200 ms (at rest: P= 0.016, Cohen's d= 0.496; during exercise: P= 0.006, Cohen's d= 0.421) time windows. Controls showed greater decrease of sEMG than CKD patients in the 0–30 ms (P= 0.020, Cohen's d= 0.533) and 0–50 ms (P= 0.010, Cohen's d= 0.640) time windows. As opposite to females, males showed almost the same differences between groups. Our study is the first to show that CKD patients have higher fatigability than controls, which may be associated with an impaired motor‐unit recruitment, highlighting a neural drive disturbance with CKD. Further studies are needed to confirm these findings.

Background: Preeclampsia (PE) and chronic kidney disease (CKD) are linked by an only partially known cause-effect relationship. Knowledge on prevalence of CKD in PE patients is needed for evaluating the diagnostic yield of nephrology work-up after PE. Methods: The study was undertaken in the Centre Hospitalier Le Mans (CHM), setting of tertiary level obstetric service (about 3500 deliveries/year). PE was identified on hospital’s discharge codes; after review, the study included 99 patients, 36 of which were also evaluated in Nephrology. A descriptive analysis was performed as appropriate. Logistic multiple regression tested the outcome “CKD diagnosis”; covariates that emerged as significant were selected; only singletons were included. Analysis was performed in SPSS. The ethics committee of the CHM approved the study. Results: Prevalence of CKD was 14%; CKD was in stage 1 in 8/14 (57%); 5 patients were in stage 2 (36%), 1 in stage 3 (7%). CKD was known or acknowledged in 1 case only. Diagnoses included reflux nephropathy-other malformations (5 cases), kidney stones-chronic pyelonephritis (3), PKD (1), interstitial nephropathy (2), diabetic nephropathy (1), albuminuria in metabolic syndrome (2). At the logistic regression analysis, preterm delivery [OR 7.849 (1.667–36.968)] and a baby normal for gestational age [> 10th centile; OR 6.193 (1.400–27.394)] were significantly correlated with the diagnosis of CKD. Conclusions: Within the limits of a single-center study, our data quantify CKD as common in PE women and suggest the presence of a “CKD phenotype” characterised by preterm delivery and adequate growth, implying that CKD is compatible with good placental function up to the last phase of pregnancy.