Novel assay of metformin levels in patients with type 2 diabetes and varying levels of renal function: clinical recommendations.

OBJECTIVE: To study trough levels of metformin in serum and its intra-individual variation in patients using a newly developed assay. RESEARCH DESIGN AND METHODS: Trough serum levels of metformin were measured once using liquid chromatography-tandem mass spectrometry (LCMSMS) in 137 type 2 diabetic patients with varying renal function (99 men) and followed repeatedly during 2 months in 20 patients (16 men) with estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m(2) body surface. RESULTS: Patients with eGFR >60, 30-60, and <30 ml/min/1.73 m(2) had median trough metformin concentrations of 4.5 micromol/l (range 0.1-20.7, n = 107), 7.71 micromol/l (0.12-15.15, n = 21), and 8.88 micromol/l (5.99-18.60, n = 9), respectively. The median intra-individual overall coefficient of variation was 29.4% (range 9.8-74.2). CONCLUSIONS: Determination of serum metformin with the LCMSMS technique is useful in patients on metformin treatment. Few patients had values >20 micromol/l. Metformin measurement is less suitable for dose titration.

Chemorefractory rhabdomyosarcoma treated with radiotherapy, bevacizumab, statins and surgery and maintenance with bevacizumab and chemotherapy.

BACKGROUND: Rhabdomyosarcoma is a rare disease in children and young adults, usually responsive to chemotherapy. Here we report on a patient with chemorefractory disease, treated in an unconventional approach. CASE REPORT: A young woman presented with an embryonal rhabdomyosarcoma of the retromaxillary space. She exhibited progressive disease to two chemotherapy regimens. The patient started hyperfractionated radiotherapy that due to lack of response was changed to 3 Gy fractions once daily to a total absorbed dose of 53 Gy. The therapeutic predicament led us to add bevacizumab and hydroxymethylglutaryl-CoA reductase inhibitors (statins), for which some experimental support could be found. RESULTS: The tumour responded clearly, and a radical R0 resection followed. The patient was treated postoperatively with bevacizumab and chemotherapy. The combined treatment was accompanied by side effects such as mucositis grade IV, impaired healing of the mandibulotomy as well as a prominent cystitis. Side effects subsided following treatment with hyperbaric oxygen. CONCLUSION: Rhabdomyosarcoma refractory to chemotherapy may respond to radiotherapy and the addition of bevacizumab and statins. Although the contribution of the adjuncts is unclear, the unexpected tumour control in this case may help in decision-making in similar cases and may encourage the investigation of these adjuncts in protocols.

Antibiotic prophylaxis in oral health care: administration strategies of general dental practitioners.

OBJECTIVE: To examine the strategies that general dental practitioners (GDPs) use to administer antibiotic prophylaxis and to study the agreement between the administration strategies of GDPs and local recommendations. METHODS: Postal questionnaires in combination with telephone interviews were used. Two hundred GDPs in two Swedish counties, Skåne and Orebro, were asked to participate. The response rate was 51% (n = 101). The GDPs were presented with eight simulated cases of patients with different medical conditions for which antibiotic prophylaxis might be considered necessary when performing dental procedures (scaling, tooth removal, root canal treatment). The administration strategies of the GDPs were compared with local recommendations. RESULTS: In general, the variation in the administration strategies of the GDPs was large. For two medical conditions, type 1 diabetes that was not well controlled and hip prosthesis, significantly more GDPs in Skåne than in Orebro administered antibiotic prophylaxis for tooth removal. Agreement between the administration strategies of the GDPs and local recommendations was low. Differences between the two counties were non-significant. Furthermore, within Orebro, GDPs who did not have formal access to local recommendations did not differ in their administration strategies from those who did. The choice of substance was seldom in agreement with the substance recommended, while the majority followed the recommended duration of treatment. CONCLUSION: Although recommendations existed, their impact appeared to be limited. This is significant, since the implementation of recommendations is crucial in making clinical practice more effective and in promoting the health of patients.