Israel Medical Association Journal

Background: Among chronic kidney disease (CKD) patients, baseline neutrophil gelatinase-associated lipocalin (NGAL) may reflect the severity of renal impairment. No data exists on serial changes in serum NGAL levels in CKD patients before and after percutaneous coronary intervention (PCI).

Objectives: To evaluate serial serum NGAL levels relation to contrast induced acute kidney injury (CI-AKI) following PCI.

Methods: The study included 58 patients with CKD who underwent elective PCI. Plasma NGAL measurements were performed before (pre-NGAL) and 24 hours following (post-NGAL) PCI. Patients were followed for CI-AKI and changes in NGAL levels. Receiver operator characteristic identified the optimal sensitivity and specificity for pre-NGAL levels compared with post-NGAL for patients with CI-AKI.

Results: Overall CI-AKI incidence was 33%. Both pre-NGAL (172 vs. 119 ng/ml, P < 0.001) and post-NGAL (181 vs. 121 ng/ml, P < 0.001) levels were significantly higher in patients with CI-AKI, but no significant changes were detected. Pre-NGAL levels were similar to post-NGAL levels in predicting CI-AKI (area under the curve 0.753 vs. 0.745). Optimal cutoff value for pre-NGAL was 129 ng/ml (sensitivity of 73% and specificity of 72%, P < 0.001). Post-NGAL levels > 141 ng/ml were independently associated with CI-AKI (hazard ratio [HR] 4.86, 95% confidence interval [95%CI] 1.34–17.64, P = 0.02) with a strong trend for post-NGAL levels > 129 ng/ml (HR 3.46, 95%CI 1.23–12.81, P = 0.06).

Conclusions: In high-risk patients, pre-NGAL levels may predict CI-AKI. Further studies on larger populations are needed to validate the use of NGAL measurements in CKD patients.

Background: Acute kidney injury (AKI) is a risk factor for morbidity and mortality during critical illness especially in very old patients admitted to intensive care units.

Objectives: To identify prognostic markers for AKI patients.

Methods: This single-center retrospective study was based on a patient registry of a medical intensive care unit. Hospital records of patients aged 80 years or older admitted between 2005 and 2015 were examined. Patients who developed AKI according to Kidney Disease: Improving Global Outcomes (KDIGO) guidelines within 4 days of admission were included in this study.

Results: The study comprised 96 patients with AKI and 81 age- and sex-matched controls without AKI. Mean acute physiology and chronic health evaluation (APACHE) II score was 30 with an ICU mortality of 27% in very old patients with AKI. The odds ratio of hospital mortality for these patients was 5.02 compared to controls (49% vs. 16%). APACHE II score and fluid balance in the first 2 days of ICU admission were the strongest predictors of ICU mortality with an area under the receiver operating characteristic of 0.76. Of the 47 patients with AKI who survived hospital admission, 30 were discharged home.

Conclusions: Mortality was increased in very old ICU patients with AKI. Among survivors, two-thirds returned home.

Background: Hip fracture is common in elderly patients and is associated with high morbidity and mortality. Acute kidney injury (AKI) following hip fracture may have additional impact on clinical outcomes.

Objectives: To investigate the incidence of AKI, the risk factors for its occurrence and impact on mortality, timing of surgery, and length of hospitalization (LOS) in patients undergoing hip fracture surgery.

Methods: We retrospectively examined the records of patients who underwent hip fracture surgery between 2013 and 2017. All patients had a baseline serum creatinine value and at least one later value. AKI was defined according to KDIGO guidelines.

Results: The study included 511 patients. Mean age was 72.6 years, 325 males (63.4%); 151 (29.5%) had baseline eGFR < 60 ml/min/1.73m². Of these, 87 (17%) developed AKI. Older age, diabetes mellitus, hypertension, and chronic heart condition were significantly more common in patients who developed AKI. Patients with AKI had increased 30-day mortality (hazard ratio [HR] 3.96, 95% confidence interval [95%CI] 1.62–9.7, P = 0.003) and mortality at one year (HR 2.72, 95%CI 1.5–4.9, P = 0.002). AKI was associated with surgery delay > 48 hours (HR 2.241, 95%CI 1.206–4.165, P = 0.011). Mean LOS was 10.9 days and 8 days for patients with AKI and without, respectively, P < 0.0001.

Conclusions: AKI is a common complication in patients with hip fracture and is associated with increased short- and long-term mortality, delayed surgery, and longer hospitalization. Interventions identifying and monitoring patients at risk may contribute to improve the outcomes

Background: Data suggest that subclinical hypothyroidism (SCH) is associated with progression of chronic renal disease; however, no study to date has assessed the possible relation between SCH and acute deterioration of renal function.

Objectives: To investigate the possible relation between SCH and acute kidney injury (AKI) in a large cohort of patients with ST-elevation myocardial infarction (STEMI) treated with primary coronary intervention (PCI).

Methods: We evaluated thyroid stimulating hormone (TSH) and free T4 levels of 1591 STEMI patients with no known history of hypothyroidism or thyroid replacement treatment who were admitted to the coronary care unit (October 2007–August 2017). The presence of SCH was defined as TSH levels ≥ 5 mU/ml in the presence of normal free T4 levels. Patients were assessed for development of AKI ( 0.3 mg/dl increase in serum creatinine, according to the KDIGO criteria).

Results: The presence of SCH was demonstrated in 68/1593 (4.2%) STEMI patients. Patients presenting with SCH had more AKI complications during the course of STEMI (20.6% vs. 9.6 %; P = 0.003) and had significantly higher serum creatinine change throughout hospitalization (0.19 mg/dl vs. 0.08 mg/dl, P = 0.04). No significant difference was present in groups regarding baseline renal function and the amount of contrast volume delivered during coronary angiography. In multivariate logistic regression model, SCH was independently associated with AKI (odds ratio = 2.19, 95% confidence interval 1.05–4.54, P =0.04).

Conclusions: Among STEMI patients treated with PCI, the presence of SCH is common and may serve as a significant marker for AKI.

Background: Sodium-glucose cotransporter 2 inhibitors (SGLT2i) (such as canagliflozin, empagliflozin, and dapagliflozin) are widely used to treat patients with type 2 diabetes mellitus (T2DM) to improve glycemic, cardiovascular and renal outcomes. However, based on post-marketing data, a warning label was added regarding possible occurrence of acute kidney injury (AKI).

Objectives: To describe the clinical presentation of T2DM patients treated with SGLT2i who were evaluated for AKI at our institution and to discuss the potential pathophysiologic mechanisms.

Methods: A retrospective study of a computerized database was conducted of patients with T2DM who were hospitalized or evaluated for AKI while receiving SGLT2i, including descriptions of clinical and laboratory characteristics, at our institution.

Results: We identified seven patients in whom AKI occurred 7–365 days after initiation of SGLT2i. In all cases, renin-angiotensin-aldosterone system blockers had also been prescribed. In five patients, another concomitant nephrotoxic agent (injection of contrast-product, use of nonsteroidal anti-inflammatory drugs or cox-2 inhibitors) or occurrence of an acute medical event potentially associated with AKI (diarrhea, sepsis) was identified. In two patients, only the initiation of SGLT2i was evident. The mechanisms by which AKI occurs under SGLT2i are discussed with regard to the associated potential triggers: altered trans-glomerular filtration or, alternatively, kidney medullary hypoxia.

Conclusions: SGLT2i are usually safe and provide multiple benefits for patients with T2DM. However, during particular medical circumstances, and in association with usual co-medications, particularly if baseline glomerular filtration rate is decreased, patients treated with SGLT2i may be at risk of AKI, thus warranting caution when prescribed.

Background: Early surgical correction of congenital heart malformations in neonates and small infants may be complicated by acute kidney injury (AKI), which is associated with higher morbidity and mortality rates, especially in patients who require dialysis. Glomerular filtration rate (GFR) is considered the best measurement of renal function which, in neonates and infants, is highly dependent on heart function. 

Objective: To determine whether measurements of creatinine clearance after open heart surgery in neonates and young infants can serve as an early indicator of surgical success or AKI.

Method: We conducted a prospective observational study in 19 neonates and small infants (body weight < 5 kg) scheduled for open heart surgery with cardiopulmonary bypass. Urine collection measurement of creatinine clearance and albumin excretion was performed before and during surgery and four times during 48 hours after surgery.

Results: Mean creatinine clearance was lowest during surgery (25.2 ± 4. ml/min/1.73 m2) and increased significantly in the first 16 hours post-surgery (45.7 ± 6.3 ml/min/1.73 m2). A similar pattern was noted for urine albumin which was highest during surgery (203 ± 31 µg/min) and lowest (93 ± 20 µg/min) 48 hours post-surgery. AKI occurred in four patients, and two patients even required dialysis. All six showed a decline in creatinine clearance and an increase in urine albumin between 8 and 16 hours post-surgery. 

Conclusions: In neonates and small infants undergoing open heart surgery, a significant improvement in creatinine clearance in the first 16 hours postoperatively is indicative of a good surgical outcome. This finding has important implications for the early evaluation and treatment of patients in the intensive care unit on the first day post-surgery.