Paroxysmal autonomic instability with dystonia in a patient with tuberculous meningitis: a case report

<p>Abstract</p> <p>Introduction</p> <p>This case report describes an extremely rare combination of paroxysmal autonomic instability with dystonia and tuberculous meningitis. Paroxysmal autonomic instability with dystonia is normally associated with severe traumatic brain injury.</p> <p>Case presentation</p> <p>A 69-year-old man of Indonesian descent was initially suspected of having a community-acquired pneumonia, which was seen on chest X-ray and computed tomography of the chest. However, a bronchoscopy showed no abnormalities. He was treated with amoxicillin-clavulanic acid in combination with ciprofloxacin. However, nine days after admission he was disorientated and complained of headache. Neurological examination revealed no further abnormalities. A lumbar puncture revealed no evidence of meningitis. He was then transferred to our hospital. At that time, initial cultures of bronchial fluid for <it>Mycobacterium tuberculosis </it>turned positive, as well as polymerase chain reaction for <it>Mycobacterium tuberculosis</it>. Later, during his stay in our intensive care unit, he developed periods with hypertension, sinus tachycardia, excessive transpiration, decreased oxygen saturation with tachypnea, pink foamy sputum, and high fever. This constellation of symptoms was accompanied by dystonia in the first days. These episodes lasted approximately 30 minutes and improved after administration of morphine, benzodiazepines or clonidine. Magnetic resonance imaging showed an abnormal signal in the region of the hippocampus, thalamus and the anterior parts of the lentiform nucleus and caudate nucleus.</p> <p>Conclusions</p> <p>In patients with (tuberculous) meningitis and episodes of extreme hypertension and fever, paroxysmal autonomic instability with dystonia should be considered.</p

External rotation stress imaging in syndesmotic injuries of the ankle - Comparison of lateral radiography and radiostereometry in a cadaveric model

We compared the value of 7.5 Nm external rotation stress in diagnosing tibiofibular syndesmotic injuries of the ankle on lateral radiographs with radiostereometric analysis (RSA) in 10 cadaveric legs. After sectioning 2 ligaments, RSA showed an increase in posterior translation and external rotation of the fibula. This increase in posterior translation was smaller than the posterior displacement of the fibula on the lateral radiograph, and RSA showed mainly an increase in external rotation of the fibula that can not be measured on conventional radiographs. We conclude that instability of the syndesmosis in cadaveric ankles can be detected with 7.5 Nm external rotation stress RSA, but that external rotation stress lateral radiography is unreliable

Development of a simple and rapid method to measure the free fraction of tacrolimus in plasma using ultrafiltration and LC-MS/MS

BACKGROUND: Tacrolimus is an immunosuppressant mainly used in the prophylaxis of solid organ transplant rejection. Therapeutic drug monitoring of tacrolimus is essential for avoiding toxicity related to overexposure and transplant rejection from underexposure. Previous studies suggest that unbound tacrolimus concentrations in the plasma may serve as a better predictor of tacrolimus-associated nephro- and neurotoxicity compared to tacrolimus concentration in whole blood. Monitoring the plasma concentrations of unbound tacrolimus might be of interest in preventing tacrolimus-related toxicity. Therefore, the aim was to develop a method for the measurement of total and unbound tacrolimus concentrations in plasma. METHODS: The sample preparation for the determination of the plasma concentrations of unbound tacrolimus consisted of an easy-to-use ultrafiltration method followed by solid phase extraction. To determine the total concentration of tacrolimus in plasma, a simple method based on protein precipitation was developed. The extracts were injected into a Thermo Scientific HyPurity C18 column using gradient elution. The analytes were detected by liquid chromatography-mass spectrometry using a triple quadrupole with positive ionization. RESULTS: The method was validated over a linear range of 1.00-200 ng/L for unbound tacrolimus concentrations in plasma and 100-3200 ng/L for total plasma concentrations. The lower limit of quantification was 1.00 ng/L in ultrafiltrate and 100 ng/L in plasma.The inaccuracy and imprecision for the determination of unbound tacrolimus concentrations in ultrafiltrate and plasma showed a maximum CV of 11.7% and a maximum bias of 3.8%. CONCLUSION: A rapid and easy method based on ultrafiltration and LC-MS/MS was established to measure the total and unbound tacrolimus concentrations in plasma. This method can facilitate further investigations on the relationship between plasma concentrations of unbound tacrolimus and clinical outcomes in transplant recipients

Association of Whole Blood Tacrolimus Concentrations with Kidney Injury in Heart Transplantation Patients

Background and Objectives: Acute kidney injury (AKI) is frequently observed after heart transplantation and is associated with morbidity and mortality. However, many confounding factors also contribute to the development of AKI in heart transplants. We hypothesized that supratherapeutic whole-blood tacrolimus trough concentrations are associated with AKI. Methods: In a retrospective observational cohort from April 2005 to December 2012, all adult heart transplantation patients were included. AKI was assessed in the first 2 weeks after transplantation as classified by the Kidney Disease Improving Global Outcomes Network (KDIGO). Whole-blood tacrolimus trough concentrations were determined from day 1 to day 14 and at 1, 3, 6 and 12 months post-transplantation. The therapeutic range was 9 to 15 ng/ml in the first 2 months and tapered to 5–8 ng/ml thereafter. The relationship between supratherapeutic tacrolimus trough concentrations and AKI was evaluated. The impact of various potentially confounding factors on tacrolimus concentrations and AKI was considered. Results: We included 110 patients. AKI occurred in 57% of patients in the first week. Recovery from AKI was seen in 24%. The occurrence of chronic kidney disease (CKD) was 19% at 1 year. Whole-blood tacrolimus trough concentrations were often supratherapeutic and, despite correction for confounding factors, independently associated with AKI (OR 1.66; 95% CI 1.20–2.31). Conclusions: Supratherapeutic whole-blood tacrolimus trough concentrations are independently associated with the development of AKI in adult heart transplantation patients. More stringent dosing of tacrolimus early after transplantation may be critical in preserving the kidney function

Clinical Pharmacokinetics and Impact of Hematocrit on Monitoring and Dosing of Tacrolimus Early After Heart and Lung Transplantation

The calcineurin inhibitor tacrolimus is an effective immunosuppressant and is extensively used in solid organ transplantation. In the first week after heart and lung transplantation, tacrolimus dosing is difficult due to considerable physiological changes because of clinical instability, and toxicity often occurs, even when tacrolimus concentrations are within the therapeutic range. The physiological and pharmacokinetic changes are outlined. Excessive variability in bioavailability may lead to higher interoccasion (dose-to-dose) variability than interindividual variability of pharmacokinetic parameters. Intravenous tacrolimus dosing may circumvent this high variability in bioavailability. Moreover, the interpretation of whole-blood concentrations is discussed. The unbound concentration is related to hematocrit, and changes in hematocrit may increase toxicity, even within the therapeutic range of whole-blood concentrations. Therefore, in clinically unstable patients with varying hematocrit, aiming at the lower therapeutic level is recommended and tacrolimus personalized dosing based on hematocrit-corrected whole-blood concentrations may be used to control the unbound tacrolimus plasma concentrations and subsequently reduce toxicity