Rifampin pharmacokinetics in children, with and without human immunodeficiency virus infection, hospitalized for the management of severe forms of tuberculosis

<p>Abstract</p> <p>Background</p> <p>Rifampin is a key drug in antituberculosis chemotherapy because it rapidly kills the majority of bacilli in tuberculosis lesions, prevents relapse and thus enables 6-month short-course chemotherapy. Little is known about the pharmacokinetics of rifampin in children. The objective of this study was to evaluate the pharmacokinetics of rifampin in children with tuberculosis, both human immunodeficiency virus type-1-infected and human immunodeficiency virus-uninfected.</p> <p>Methods</p> <p>Fifty-four children, 21 human immunodeficiency virus-infected and 33 human immunodeficiency virus-uninfected, mean ages 3.73 and 4.05 years (<it>P </it>= 0.68), respectively, admitted to a tuberculosis hospital in Cape Town, South Africa with severe forms of tuberculosis were studied approximately 1 month and 4 months after commencing antituberculosis treatment. Blood specimens for analysis were drawn in the morning, 45 minutes, 1.5, 3.0, 4.0 and 6.0 hours after dosing. Rifampin concentrations were determined by liquid chromatography tandem mass spectrometry. For two sample comparisons of means, the Welch version of the t-test was used; associations between variables were examined by Pearson correlation and by multiple linear regression.</p> <p>Results</p> <p>The children received a mean rifampin dosage of 9.61 mg/kg (6.47 to 15.58) body weight at 1 month and 9.63 mg/kg (4.63 to 17.8) at 4 months after commencing treatment administered as part of a fixed-dose formulation designed for paediatric use. The mean rifampin area under the curve 0 to 6 hours after dosing was 14.9 and 18.1 μg/hour/ml (<it>P </it>= 0.25) 1 month after starting treatment in human immunodeficiency virus-infected and human immunodeficiency virus-uninfected children, respectively, and 16.52 and 17.94 μg/hour/ml (<it>P </it>= 0.59) after 4 months of treatment. The mean calculated 2-hour rifampin concentrations in these human immunodeficiency virus-infected and human immunodeficiency virus-uninfected children were 3.9 and 4.8 μg/ml (<it>P </it>= 0.20) at 1 month after the start of treatment and 4.0 and 4.6 μg/ml (<it>P </it>= 0.33) after 4 months of treatment. These values are considerably less than the suggested lower limit for 2-hour rifampin concentrations in adults of 8.0 μg/ml and even 4 μg/ml</p> <p>Conclusion</p> <p>Both human immunodeficiency virus-infected and human immunodeficiency virus-uninfected children with tuberculosis have very low rifampin serum concentrations after receiving standard rifampin dosages similar to those used in adults. Pharmacokinetic studies of higher dosages of rifampin are urgently needed in children to assist in placing the dosage of rifampin used in childhood on a more scientific foundation.</p

Prognostic value in predicting overall survival of two mucinous markers: CA 15-3 and CA 125 in breast cancer patients at first relapse of disease.

The role of circulating tumour markers in providing prognostic information has been scarcely studied. We evaluated the prognostic significance of two mucinous markers: CA 15-3 and CA 125 in 115 breast cancer patients at first recurrence of disease. At diagnosis of advanced disease bone involvement was found in 64 patients, lung in 57, skin lymph nodes in 21, liver in 20, and brain in 5. Patients were recruited and treated in the same institution with conventional chemo- or endocrine therapy. The follow-up ranged from 3 to 54+ months (median 35). Serum samples were drawn at first recurrence of disease before the start of any endocrine and/or chemotherapy. Patients with CA 15-3 30 U/ml (median 50+ versus 26 months, P 35 U/ml (median 34.5 versus 18.5 months, P < 0.001). CA 125, but not CA 15-3, maintained its prognostic value in the subgroup of patients with visceral metastases. Both markers were found to be independent prognostic variables in multivariate analysis according to Cox's model. CA 15-3 and CA 125 appeared to be powerful prognostic indicators, in addition to visceral metastases, in patients with advanced breast cancer

Rifampicin in collections of pus--a kinetic study in human abscesses

Abstract: Most of the successful non-surgical management of abdominal abscesses is based upon the presence of therapeutic amounts of effective antibiotics within the collection. However few data are currently available concerning antimicrobial levels in human purulent lesions. To study the relationship between serum and pus concentrations of rifampicin, 11 patients with deep-seated abscesses were given 900 mg intravenously of rifampicin daily; after 3, 8 and 20 h from injection, an ultrasound-guided percutaneous aspiration of the collection was performed. Samples were obtained on the first day of therapy in six cases, while in other six the aspiration took place on the third day. Rifampicin levels of therapeutic value were present after 8 h from the first injection. From this time antibiotic amounts in pus, ranging from 1.6 to 5.8 mg/l, were consistent with a long persistence of rifampicin in abscesses, without any evidence of accumulatio

Cisplatin, epirubicin, and lonidamine combination regimen as first-line chemotherapy for metastatic breast cancer: a pilot study.

We assessed the activity and tolerability of a cisplatin, epirubicin, and lonidamine combination regimen as first-line chemotherapy in 28 advanced breast cancer patients. The schedule of treatment was as follows: 60 mg/ m2 epirubicin followed by 40 mg/m2 cisplatin given on days 1 and 2 every 21 days, with 450 mg lonidamine being given per os (three tablets) on days of chemotherapy administration and in the period intervening between one cycle and the next. Patients received a median of 5 (range 1-6) cycles. Overall, 22 patients were evaluable for response and 28, for toxicity. Four patients refused to continue the treatment after the first course, one was lost to follow-up, and one died due to toxicity (septic shock). The incidence of grade 3/4 nausea and vomiting was found to be greater than that expected with epirubicin and lonidamine alone. The addition of cisplatin resulted in an increase in platelet and hemoglobin toxicities, whereas the WBC toxicity did not differ from that expected with epirubicin and lonidamine. The hematological toxicity was found to be cumulative, leading to treatment delay in about 50% of patients at the fifth and sixth courses. The activity of this cytotoxic regimen was noteworthy, with the overall response rate being 81.8% (31.8% complete responses and 50.0% partial responses) in evaluable patients. This response rate decreased to 64.2% when all registered patients were included according to an intent-to-treat analysis. In conclusion, the association of cisplatin, epirubicin, and lonidamine given on the schedule described herein, appears to be very active but substantially toxic. We are now testing this combination in a randomized comparison, with the cisplatin dose being reduced to 30 mg/m2 given on days 1 and 2