Nicolás Medrano

Symptomatic thromboembolic events in patients treated with intravenous-immunoglobulins: Results from a retrospective cohort study

AIMS To estimate the incidence and predictors of symptomatic arterial and venous thromboembolic events (TEE) from intravenous immunoglobulin (IVIg) therapy according to its indications. METHODS We performed a retrospective cohort study of patients seen at our institution and treated with IVIg over a 36-month period. Indications, comorbility and comedication associated with TEE were identified by a stepwise logistic regression analysis. RESULTS Of 303 patients included with at least one infusion of IVIg over three years, TEE were identified in a total of 50 patients treated with IVIg, for an incidence of 16.9% (CI 95%: 13.0-21.6); 27 (54%) arterial (9.1%;CI 95%: 6.3-13.0%) and 23 (46%) venous TEE (7.8%; CI95%: 5.2-11.4%), overall mortality was 32%. Per indication there were more patients with autoimmune conditions, secondary immunodeficiency, dysimmune neuropathies, acute rejection of solid organ transplantation and sepsis. Patients with TEE were significantly older, were more likely to be men, they had more comorbid conditions; the doses of IVIg were high (589.4mg/kg/day vs 387.0mg/kg/day, p<0.001) and differences in comedication were found. The stepwise logistic regression analysis retained high doses of IVIg (OR 3.03; CI 95%: 1.49-5.67) and diuretics therapy (OR 1.69; CI 95%: 1.06-3.97) when combined with the usual comorbid confounders. CONCLUSIONS The incidence of TEE from IVIg therapy remains high at one in six patients treated. The most remediable factor is a high daily IVIg load. Decreasing the daily IVIg dose together with carefully weighing diuretics therapy and comorbid risk factors may be the keys to saving lives.

Vancomycin-induced acute kidney injury detected by a prospective pharmacovigilance program from laboratory signals.

Background: Retrospective studies have identified elevated vancomycin trough levels >20 mg/L as a predictor of nephrotoxicity with a high variable incidence of 12.6%–65%. However, the elevated levels may represent the effect of renal compromise rather than the cause of nephrotoxicity. The aim of this study was to report the incidence of acute kidney injury (AKI) and associated risk factors in adult patients with vancomycin trough levels >20 mg/L in a prospective Pharmacovigilance Program from Laboratory Signals at a Hospital. Methods: This was a prospective follow-up of all cases with serum vancomycin trough levels >20 mg/L between June 2010 and May 2011. AKI was defined using the Risk, Injury, Failure, Loss, End-stage criteria. Patients with vancomycin-induced AKI (VIAKI) were compared with vancomycin-tolerant patients. Results: During 12 months of study, 271 samples corresponding to 179 cases were monitored. Vancomycin did not alter the renal function in 68.2% [95% confidence interval (CI): 60.8–74.9] of cases, and 13.4% (95% CI: 8.8–19.3) of AKI cases were induced by other causes. Nephrotoxicity without AKI criteria was found in 10.1% (95% CI: 6.1–15.4) of cases, and VIAKI occurred in 8.4% (95% CI: 4.8–13.4) of cases. The VIAKI group had a significantly lower basal glomerular filtration rate at baseline and higher vancomycin trough levels at the time of the signal. The majority of the group was in the intensive care unit and received nephrotoxic agents during vancomycin therapy. The most frequent stage of VIAKI was injury (53.3%). VIAKI occurred after 7 days (range: 3–14) of treatment, and in 53.3% of cases, the daily dose was >30 mg/kg. Renal function was recovered at discharge in 73.3% of cases and 66.7% of cases had other suspected drugs. Conclusions: The Pharmacovigilance Program from Laboratory Signals at a Hospital provides early identification and early evaluation of cases. Renal function and vancomycin trough levels should be closely monitored from the second week of treatment in adults, intensive care patients, and those who receive concurrent nephrotoxic agents.

Hepatotoxicity induced by acute and chronic paracetamol overdose in adults. Where do we stand

Paracetamol (Acetaminophen) poisoning data can reveal the potential deficiencies of paracetamol poisoning management guidelines. We conducted a retrospective cohort study of patients >18years who were attended in the emergency department (ED) of a Spanish tertiary hospital, from 2005 to 2010 for suspected paracetamol overdose and who had measurable paracetamol concentrations. 208 patients suspected of paracetamol poisoning were identified. The annual incidence in the ED increased from 2.0 (95%-CI: 0.2-7.2) cases per 10,000 patients in 2005 to 3.4 (95%-CI: 1.1-8.8) in 2010. Only 7 of 98 patients (7.14%) with acute poisoning at toxic doses showed hepatotoxicity signs, 4 (57.1%) of whom presented acute liver failure (ALF) criteria, while 8 of 10 patients (80%) with chronic paracetamol poisoning at toxic doses presented hepatotoxicity and 3 (37.5%) with ALF criteria. The time required to find medical care was 9.0h for acute poisoning and 49.6h for chronic poisoning (p<0.001). We conclude that the incidence of suspected cases of paracetamol poisoning at our hospital is increasing. The majority of toxicity cases, including ALF, associated with the ingestion of paracetamol were due to chronic poisoning. This finding constitutes an important warning regarding paracetamol chronic poisoning, and clinicians should have a higher index of clinical suspicion for this entity.

Liver Transplant in a Patient under Methylphenidate Therapy: A Case Report and Review of the Literature

Background. Methylphenidate (MPH) is widely used in treating children with attention-deficit-hyperactivity disorder. Hepatotoxicity is a rare phenomenon; only few cases are described with no liver failure. Case. We report on the case of a 12-year-old boy who received MPH for attention-deficit-hyperactivity disorder. Two months later the patient presented with signs and symptoms of hepatitis and MPH was discontinued, showing progressive worsening and developing liver failure and a liver transplantation was required. Other causes of liver failure were ruled out and the liver biopsy was suggestive of drug toxicity. Discussion. One rare adverse reaction of MPH is hepatotoxicity. The review of the literature shows few cases of liver injury attributed to MPH; all of them recovered after withdrawing the treatment. The probable mechanism of liver injury was MPH direct toxicity to hepatocytes. In order to establish the diagnosis of MPH-induced liver injury, we used CIOMS/RUCAM scale that led to an assessment of “possible” relationship. This report provides the first published case of acute MPH-induced liver failure with successful hepatic transplantation. Conclusions. It is important to know that hepatotoxicity can occur in patients with MPH treatment and monitoring the livers function is highly recommended.

Hepatotoxicity induced by acute and chronic paracetamol overdose in children: Where do we stand?

BackgroundThere are few data on hepatotoxicity induced by acute or chronic paracetamol poisoning in the pediatric population. Paracetamol poisoning data can reveal the weaknesses of paracetamol poisoning management guidelines.MethodsWe retrospectively studied the patients of less than 18 years old with measurable paracetamol levels, who were brought to the emergency department (ED) of La Paz University Hospital, Madrid, Spain, for suspected paracetamol overdoses between 2005 and 2010.ResultsNinety-two patients with suspected paracetamol poisoning were identified. In 2007, the incidence of paracetamol poisoning in the pediatric population was 0.8 [Poisson-95% confidence interval (CI): 0.03-3.69] per 10 000 inhabitants aged less than 18 years. The incidence in the same year was 1.53 (Poisson-95% CI: 0.24-5.57) per 10 000 patients in the pediatric ED. The most common cause of poisoning was attempted suicide (47.8%) in teenagers with a median age of 15 years, followed by accidental poisoning (42.2%) in babies with a median age of 2.65 years. Difference was seen in the frequency of hepatotoxicity between acute and chronic poisoning cases. Only 1 of 49 patients with acute poisoning showed hepatotoxicity [acute liver failure (ALF)], whereas 7 of 8 patients with chronic poisoning showed hepatotoxicity (3 cases of ALF). The average time to medical care was 6.83 hours for acute poisoning and 52.3 hours for chronic poisoning (P<0.001).ConclusionsChronic paracetamol poisoning is a potential risk factor for hepatotoxicity and acute liver failure. Delays in seeking medical help might be a contributing factor. Clinicians should have a higher index of clinical suspicion for this entity.