Continuous Positive Airway Pressure Effect on Albuminuria Progression in Patients with Obstructive Sleep Apnea and Diabetic Kidney Disease: A Randomized Clinical Trial.

Rationale: Obstructive sleep apnea (OSA) is associated with impaired glycemic control and a higher risk of vascular complications, such as diabetic kidney disease (DKD). However, the effect of apnea-hypopnea suppression on DKD progression is unclear. Objectives: To assess the effect of continuous positive airway pressure (CPAP) on the urinary albumin-to-creatinine ratio (UACR) in patients with DKD and OSA. Methods: In a 52-week, multicentric, open-label, parallel, and randomized clinical trial, 185 patients with OSA and DKD were randomized to CPAP and usual care (n = 93) or usual care alone (n = 92). Measurements and Main Results: UACR, estimated glomerular filtration rate, serum concentrations of creatinine and glycated hemoglobin, insulin resistance, lipid concentrations, sleepiness, and quality of life. A 52-week change in UACR from baseline did not differ significantly between the CPAP group and the usual-care group. However, in per-protocol analyses that included 125 participants who met prespecified criteria for adherence, CPAP treatment was associated with a great reduction in UACR (mean difference, -10.56% [95% confidence interval, -19.06 to -2.06]; P = 0.015). CPAP effect on UACR was higher in nonsleepy patients with more severe OSA, worse renal function, and a more recent diagnosis of DKD. CPAP treatment also improved glycemic control and insulin resistance, as well as sleepiness and health-related quality of life. Conclusions: In patients with OSA and DKD, the prescription of CPAP did not result in a statistically significant reduction in albuminuria. However, good adherence to CPAP treatment in addition to usual care may result in long-term albuminuria reduction compared with usual care alone. Clinical trial registered with www.clinicaltrials.gov (NCT02816762).

Obstructive sleep apnea is associated with impaired renal function in patients with diabetic kidney disease.

Obstructive sleep apnea (OSA) is a recognized risk factor for the development of diabetic kidney disease (DKD). Our objectives were to compare the urinary albumin-creatinine ratio (UACR) and estimated glomerular filtration rate (eGFR) of patients with DKD according to OSA severity, and to evaluate the contribution of sleep parameters to their renal function. In a multicenter, observational, cross-sectional study, 214 patients with DKD were recruited. After a sleep study, UACR and eGFR were measured, as well as serum creatinine, fasting glucose, glycated hemoglobin, insulin resistance, lipid profile and C-reactive protein. UACR was higher in severe OSA patients (920 ± 1053 mg/g) than in moderate (195 ± 232 mg/g, p < 0.001) or mild OSA/non-OSA subjects (119 ± 186 mg/g, p < 0.001). At the same time, eGFR showed an OSA severity-dependent reduction (48 ± 23 vs. 59 ± 21 vs. 73 ± 19 ml/min per 1.73 m2, respectively; p < 0.001). Apnea-hypopnea index (AHI and desaturation index (ODI) were identified as independent predictors for UACR and eGFR, respectively. Therefore, in patients with DKD under optimized treatment, severe OSA is associated with a higher UACR and a lower eGFR, reflecting an additional contribution to the impairment of their renal function, although no causality can be inferred.

Cholesterol atheroembolism and combined treatment with steroids and iloprost.

Cholesterol atheroembolism (CAE) is a systemic disorder whose incidence has increased in recent decades and that presents high morbidity and mortality. Although several therapeutic alternatives have been reported, there is no consensus about the best treatment for this disease. In this paper we report the case of a patient with CAE with skin, bowel and kidney involvement who presented a good response to combined therapy with steroids and prostaglandin analogues. Although there are no conclusive studies, we recommend this therapeutic alternative in the management of CAE with organic failure.

Acute renal failure due to interstitial nephritis after intravesical instillation of BCG.

Intravesical chemotherapy with bacilli Calmette-Guerin (BCG) has been an established therapy for preventing recurrence of, and for treatment of, superficial transitional cell carcinoma of the bladder, but it is not without side effects. A variety of renal complications have been reported and attributed to mycobacterial infection. Although renal complications are uncommon, several cases of interstitial nephritis (with or without granulomas) and mesangial glomerulonephritis have been reported. We report a 76-year-old male patient who developed acute renal failure due to interstitial nephritis after intravesical instillation of BCG. Corticosteroids may serve the recovery of renal function without concomitant use of anti-tubercular therapy, provided systemic signs and mycobacterial infection are absent. Serum creatinine should be checked in at-risk patients in order to detect this complication early.