Langerhans cell histiocytosis involving the liver of a male smoker: a case report

<p>Abstract</p> <p>Introduction</p> <p>Langerhans' cell histiocytosis is a proliferative histiocytic disorder of unknown cause originating from dendritic cells.</p> <p>Case presentation</p> <p>The authors report a case of Langerhans' cell histiocytosis in a 48-year-old man with multisystemic disease presentation, including liver involvement.</p> <p>Conclusion</p> <p>Hepatic involvement is an uncommon feature in this rare disease and there is no consensus on the most effective therapeutic approach.</p

Langerhans cell histiocytosis of the atlas in an adult

Langerhans cell histiocytosis (LCH), formerly known as histiocytosis X, is a rare disorder (approximately 1:1,500,000 inhabitants) characterized by clonal proliferation and excess accumulation of pathologic Langerhans cells causing local or systemic effects. The exact etiology of LCH is still unknown. LCH could affect patients of any age, although most present when they are children. The most frequent sites of the bony lesions are the skull, femur, mandible, pelvis and spine. A variety of treatment modalities has been reported, but there was no evidence suggesting that any one treatment was more advantageous than another. We present an adult with LCH of the atlas. A 26-year-old young man presented with a 2-month history of neck pain and stiffness. CT revealed osteolytic lesion in the left lateral mass of atlas with compression fracture. Histopathological diagnosis was Langerhans cell histiocytosis by percutaneous needle biopsy under CT guidance. The patient underwent conservative treatment, including Halo-vest immobilization and radiotherapy. At 7-year follow-up, the patient was asymptomatic except for mild motion restriction of the neck. CT revealed a significant reconstruction of the C1 lateral mass

Applicability of a Single Time Point Strategy for the Prediction of Area Under the Concentration Curve of Linezolid in Patients: Superiority of C trough- over C max-Derived Linear Regression Models

BACKGROUND AND OBJECTIVES: Linezolid, a oxazolidinone, was the first in class to be approved for the treatment of bacterial infections arising from both susceptible and resistant strains of Gram-positive bacteria. Since overt exposure of linezolid may precipitate serious toxicity issues, therapeutic drug monitoring (TDM) may be required in certain situations, especially in patients who are prescribed other co-medications. METHODS: Using appropriate oral pharmacokinetic data (single dose and steady state) for linezolid, both maximum plasma drug concentration (C(max)) versus area under the plasma concentration–time curve (AUC) and minimum plasma drug concentration (C(min)) versus AUC relationship was established by linear regression models. The predictions of the AUC values were performed using published mean/median C(max) or C(min) data and appropriate regression lines. The quotient of observed and predicted values rendered fold difference calculation. The mean absolute error (MAE), root mean square error (RMSE), correlation coefficient (r), and the goodness of the AUC fold prediction were used to evaluate the two models. RESULTS: The C(max) versus AUC and trough plasma concentration (C(trough)) versus AUC models displayed excellent correlation, with r values of >0.9760. However, linezolid AUC values were predicted to be within the narrower boundary of 0.76 to 1.5-fold by a higher percentage by the C(trough) (78.3 %) versus C(max) model (48.2 %). The C(trough) model showed superior correlation of predicted versus observed values and RMSE (r = 0.9031; 28.54 %, respectively) compared with the C(max) model (r = 0.5824; 61.34 %, respectively). CONCLUSIONS: A single time point strategy of using C(trough) level is possible as a prospective tool to measure the AUC of linezolid in the patient population