Pharmacokinetics of Rifampin, Isoniazid, Pyrazinamide, and Ethambutol in Infants Dosed According to Revised WHO-Recommended Treatment Guidelines.

There are limited pharmacokinetic data for use of the first-line antituberculosis drugs during infancy (<12 months of age), when drug disposition may differ. Intensive pharmacokinetic sampling was performed in infants routinely receiving antituberculosis treatment, including rifampin, isoniazid, pyrazinamide, and ethambutol, using World Health Organization-recommended doses. Regulatory-approved single-drug formulations, including two rifampin suspensions, were used on the sampling day. Assays were conducted using liquid chromatography-mass spectrometry; pharmacokinetic parameters were generated using noncompartmental analysis. Thirty-nine infants were studied; 14 (36%) had culture-confirmed tuberculosis. Fifteen (38%) were premature (<37 weeks gestation); 5 (13%) were HIV infected. The mean corrected age and weight were 6.6 months and 6.45 kg, respectively. The mean maximum plasma concentrations (Cmax) for rifampin, isoniazid, pyrazinamide, and ethambutol were 2.9, 7.9, 41.9, and 1.3 µg/ml, respectively (current recommended adult target concentrations: 8 to 24, 3 to 6, 20 to 50, and 2 to 6 µg/ml, respectively), and the mean areas under the concentration-time curves from 0 to 8 h (AUC0-8) were 12.1, 24.7, 239.4, and 5.1 µg · h/ml, respectively. After adjusting for age and weight, rifampin exposures for the two formulations used differed inCmax(geometric mean ratio [GMR],2.55; 95% confidence interval [CI], 1.47 to 4.41;P= 0.001) and AUC0-8(GMR, 2.52; 95% CI, 1.34 to 4.73;P= 0.005). HIV status was associated with lower pyrazinamideCmax(GMR, 0.85; 95% CI, 0.75 to 0.96;P= 0.013) and AUC0-8(GMR, 0.79; 95% CI, 0.69 to 0.90;P< 0.001) values. No other important differences were observed due to age, weight, prematurity, ethnicity, or gender. In summary, isoniazid and pyrazinamide concentrations in infants compared well with proposed adult target concentrations; ethambutol concentrations were lower but similar to previously reported pediatric studies. The low rifampin exposures require further investigation. (This study has been registered at ClinicalTrials.gov under registration no. NCT01637558.).

The role of radioactive iodine-125 seed localization in breast-conserving therapy following neoadjuvant chemotherapy.

BACKGROUND: Neoadjuvant chemotherapy (NAC) is increasingly used in the framework of breast-conserving therapy (BCT). Localization of the initial tumor is essential to guide surgical resection after NAC. This study describes the results obtained with I-125 seed localization in BCT including NAC. PATIENTS AND METHODS: Between January 2009 and December 2010, 85 patients treated with NAC and BCT after I-125 seed localization were included. Radiological and pathological response and resection margins were retrospectively evaluated. RESULTS: BCT was carried out in 85 patients without secondary local excisions. Nineteen patients with unifocal tumors and seven patients with multifocal tumors showed a complete pathological response (P = 0.18). Tumor-free resection margins were obtained in 78 patients (50 patients with unifocal and 28 patients with multifocal tumors, P = 0.27). Focally involved margins were found in four patients (two patients with a unifocal and two patients with a multifocal tumor, P = 0.27). A subsequent mastectomy was carried out in three patients (two patients with multifocal tumors, P = 0.29). CONCLUSIONS: BCT after NAC can be carried out successfully after initial localization with I-125 seeds in both unifocal and multifocal breast tumors with complete resection rates of >90%.

Pathophysiology and treatment of edema following femoropopliteal bypass surgery.

Substantial lower-limb edema affects the majority of patients who undergo peripheral bypass surgery. Edema has impairing effects on the microvascular and the macrovascular circulation, causes discomfort and might delay the rehabilitation process of the patient. However, the pathophysiology of this edema is not well understood. The Cochrane Library and Medline were used to retrieve literature on edema following peripheral bypass surgery. Factors other than local wound healing alone are suggested in the literature to play a role, given the severity and duration of this edema. Hyperemia, microvascular permeability, reperfusion-associated inflammation and lymphatic disruptions are likely to facilitate the development of edema. Preventive methods could be lymphatic-sparing surgery, intraoperative antioxidative therapy and postoperative elevation. Successful treatment strategies to reduce postoperative edema are based on lymph massage and external compression. In conclusion, the pathophysiology of edema following peripheral surgery is not fully understood, although reperfusion-associated inflammation and lymphatic disruptions are likely to play a crucial role. When future less-invasive techniques prove to be successful, postoperative edema might be minimized. Until then, a careful lymphatic-sparing dissection should be executed when performing a peripheral bypass reconstruction. Postoperatively, the use of compression stockings and leg elevation are currently the golden standards.