Pharmacokinetics of cefonicid in children

CYP3A4/P-glycoprotein inhibitors related colchicine toxicity mimicking septic shock

Colchicine toxicity is uncommon when patients receive a therapeutic dose regularly. However, inadvertent drug interactions can result in unpredicted adverse outcomes. The toxicity of colchicine can manifest in various ways, ranging from mild and non-specific symptoms to severe form known as multiple organ dysfunction syndrome. This case highlights (1) the diagnostic challenge that arises when distinguishing between the severe manifestation of colchicine toxicity and septic shock and (2) concomitant prescription of colchicine with potent CYP3A4 and P-glycoprotein inhibitors (ie, clarithromycin) can lead to colchicine toxicity despite normal renal and hepatic clearance. Unfortunately, specific tests of colchicine toxicity were not routinely available. A high index of clinical suspicion and recognition of drug interactions with their common presentations are crucial for making diagnosis and management. Failure to recognise drug toxicity can result in poor outcomes.

Pharmacokinetics of cefonicid in lactating goats after intravenous, intramuscular and subcutaneous administration, and after a long-acting formulation for subcutaneous administration

The single-dose disposition kinetics of cefonicid were determined in clinically normal lactating goats (n = 6) after intravenous (IV), intramuscular (IM) and subcutaneous (SC) administration of a conventional formulation, and after subcutaneous administration of a long-acting formulation (SC-LA). Cefonicid concentrations were determined by high performance liquid chromatography with ultraviolet detection. The concentration-time data were analysed by noncompartmental pharmacokinetic methods. Steady-state volume of distribution (V_ss ) and clearance (Cl) of cefonicid after IV administration were 0.14 ± 0.03 L/kg and 0.51 ± 0.07 L/h·kg, respectively. Following IM, SC and SC-LA administration, cefonicid achieved maximum plasma concentrations of 14.46 ± 0.82, 11.98 ± 1.92 and 17.17 ± 2.45 mg/L at 0.26 ± 0.13, 0.42 ± 0.13 and 0.83 ± 0.20 hr, respectively. The absolute bioavailabilities after IM, SC and SC-LA routes were 75.34 ± 11.28%, 71.03 ± 19.14% and 102.84 ± 15.155%, respectively. After cefonicid analysis from milk samples, no concentrations were found above LOQ at any sampling time. From these data, cefonicid administered at 20 mg/kg each 12 hr after SC-LA could be effective to treat bacterial infections in lactating animals not affected by mastitis problems.

Empiric treatment with once-daily cefonicid and gentamicin for febrile non-neutropenic pediatric cancer patients with indwelling central venous catheters

The approach to treating febrile non-neutropenic hematooncologic patients with central venous catheters varies. We recently introduced once-daily administration of cefonicid and gentamicin for such children who were in good clinical condition and without focal signs of infection. Our 2-year experience of 125 episodes in 54 children is hereby reported. Absolute neutrophil counts were 550 to 16,700/mm. Bacteremia occurred in 6.4% episodes: only in patients with Hickman/Broviac catheters and not in those with port-a-caths [8/37 (21.6%) vs. 0/17 patients, P=0.046; 8/86 (9.3%) vs. 0/39 episodes, P=0.056]. The pathogens were coagulase-negative staphylococci (3), Streptococcus pneumoniae (2), Pseudomonas aeruginosa and Klebsiella pneumoniae (1), methicillin-sensitive Staphylococcus aureus (1), and Streptococcus milleri (1). All patients remained in stable clinical condition and all, except for 2 who became neutropenic and 1 with S. aureus bacteremia who developed cellulitis, defervesced while on the empiric therapy. Three episodes could not be managed as outpatients. No adverse effects were observed. We conclude that our approach is efficacious and safe and, furthermore, that empiric antibiotic therapy may not be indicated for selected patients with port-a-caths. Future study of children with Hickman/Broviac catheters will evaluate the use of cefonicid alone.