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Objective: To assess the pharmacokinetic and pharmacodynamic behaviour of moxifloxacin in 15 consecutive elderly patients with acute exacerbation of chronic bronchitis (AECB) treated with the fixed oral moxifloxacin 400 mg/day regimen with the intent of verifying which degree of exposure may be ensured by this standard regimen against AECB pathogens., Methods: This was an open-label, observational, pharmacokinetic-pharmacodynamic study. Blood samples were collected at steady state at appropriate intervals. Moxifloxacin plasma concentrations were analysed by means of high-performance liquid chromatography. Standard pharmacokinetic parameters and pharmacodynamic determinants (peak concentration [C(max)]/minimum inhibitory concentration [MIC], area under the plasma concentration-time curve during the 24-hour observational period [AUC(24)]/MIC, pharmacodynamic breakpoints [PDBPs]) were assessed., Results: The mean estimated pharmacokinetic parameters (C(max) 4.40 mg/L at 1.4 hours, AUC(24) 42.67 mg . h/L, elimination half-life 12.55 hours, total body clearance 0.16 L/h/kg) were generally similar to those observed in both young and elderly historic controls (except for higher-dose normalised C(max) and lower volume of distribution of the central compartment). Median C(max)/MIC and AUC(24)/MIC ratios for moxifloxacin in the fully assessable cases were, respectively, 67.5 and 823.9 against Streptococcus pneumoniae, 25 and 310.2 against Moraxella catharralis and 416.5 and 3647.5 against Haemophilus influenzae. Mean estimates of PDBP for achieving C(max)/MIC values of 12.2 and AUC(24)/MIC values of 125 were 0.36 and 0.35 mg/L, respectively., Conclusion: In patients with AECB the pharmacokinetic behaviour of moxifloxacin is not significantly altered by aging processes. This is consistent with moxifloxacin being metabolised mainly by means of phase II hepatic reactions, the activity of which was shown not to decline with age. Both the pharmacokinetic and pharmacodynamic analyses suggest that moxifloxacin 400 mg/day may be a valid therapeutic approach in the treatment of AECB in the elderly. Of note, the unmodified pharmacokinetic behaviour with no need for age-related dosage adjustments combined with the once-daily administration favouring compliance and the low potential for drug-drug pharmacokinetic interactions in case of polytherapy, make moxifloxacin particularly attractive in the treatment of elderly subpopulations at a very high risk of AECB.

Levofloxacin is considered an effective antibiotic in the treatment of community-acquired lower respiratory tract infections (LRTIs). A study was carried out on 17 in-patients to assess the pharmacokinetics of a 500 mg once-daily switch intravenous (i.v.)/oral regimen of levofloxacin in the treatment of LRTI patients. Blood samples were collected under steady-state conditions at appropriate intervals. Levofloxacin plasma concentrations were analysed by means of HPLC and pharmacokinetic parameters were estimated using the WinNonlin pharmacokinetic software package. A lower clearance of levofloxacin (<2 mL/min/kg), conditioning both a longer elimination half-life (approximately 9 h) and a larger AUC(0-tau) (approximately 80 mg/L x h), was observed for both routes in our patients than in healthy volunteers. These differences may be explained considering that levofloxacin is excreted mainly as unchanged drug by the renal route, and most of our patients (71%) were very elderly subjects whose renal function physiologically declines with age. The almost complete (> or =99%) absolute oral bioavailability suggests that a comparable exposure to the iv regimen may be achieved after oral administration. The overall clinical success rate was 94.1%.

Fast-scan CT is widely and frequently used to guide fine-needle aspiration biopsy (FNAB) of questionable lung nodules. To investigate technical problems, complications, diagnostic accuracy and indications of this technique, the findings were reviewed relative to 118 patients with negative transbronchial biopsy and sputum cytology who underwent CT-guided FNAB of solitary lung lesions. Over a 25-month period, 73 men and 45 women underwent CT-guided FNAB of lung lesions. The CT unit was a GE 9800; 22-gauge 7/9-cm spinal needles were used in most cases, while 22-G 15-cm Chiba needles were used in 6 cases. In 114 patients one FNAB was performed, 4 patients only requiring the maneuver to be repeated. Regarding the malignant nature of the lesions, there were 70 true positive, 36 true negative, 12 false negative and no false positive cytologic findings; sensitivity was 85.36%, specificity and positive predictive value were 100%, negative predictive value was 75% and diagnostic accuracy 89.83%. Only minor complications occurred: 5 cases of hemophtoe, 7 of peripheral bleeding, 4 of chest pain, 4 vagal reactions and 10 cases of pneumothorax, only one of them requiring drainage. In our experience, only one pass per patient is required and the presence of the cytopathologist is unnecessary, since in most of our cases (114/118) the diagnosis was made at the first FNAB performed by the radiologist. CT allowed the lesions to be approached easily and precisely, which is useful especially in small, peripheral or hilar, nodules missed or poorly defined by radiology. To conclude, CT-guided transthoracic FNAB can be suggested as the method of choice to diagnose lung lesions which are difficult to puncture endoscopically because of size or location, and in suspected metastases. Moreover, FNAB can be used as second-line method in the lesions where endoscopic biopsy cannot be performed or whose findings are negative.