Telithromycin is a new ketolide antimicrobial, specifically developed for the treatment of community-acquired respiratory tract infections. It has a wide spectrum of antibacterial activity against common respiratory pathogens including Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis and Streptococcus pyogenes. It also has activity against atypical pathogens, such as Chlamydia pneumoniae, Legionella pneumophila and Mycoplasma pneumoniae. Telithromycin maintains activity against beta-lactam and macrolide-resistant respiratory tract pathogens and does not appear to induce cross-resistance to other members of the macrolide-lincosamide-streptogramin (MLS) group of antimicrobials. It demonstrates bactericidal activity against S. pneumoniae and H. influenzae and has a prolonged concentration-dependent post-antibiotic effect (PAE) in vitro. The drug has favourable pharmacokinetics following oral administration. It is well absorbed, achieves good plasma levels and is highly concentrated in pulmonary tissues and white blood cells. In clinical trials, telithromycin given orally at a dose of 800 mg once daily for 5 - 10 days was as effective as comparator antimicrobials for the treatment of adults with community-acquired pneumonia, acute exacerbations of chronic bronchitis, acute maxillary sinusitis and group A-beta-haemolytic streptococcal pharyngitis or tonsillitis. The adverse events and safety profile were similar to comparator antimicrobials. The most common adverse events were diarrhoea, nausea, headache and dizziness. Telithromycin should provide an effective, convenient and well-tolerated once-daily oral therapy for treatment of respiratory infections.

Objective: In dynamic renal scans, 99m Tc-diethylenetriamine pentaacetic acid (DTPA) is copiously used and it yields information about the renal blood-flow and the excretory capacity. 99m Tc-dimercaptosuccinic acid (DMSA) is used for static renal imaging and can likewise uncover the renal cortical structure. This work was intended to evaluate whether DMSA can be declared as a radiopharmaceutical in dynamic renal scans or not. It also aimed at comparing the outcomes procured from DMSA and with DTPA examinations. Materials and Methods: A comparison of the information gained from the renograms of 47 subjects (normal subjects and subjects with abnormal renal function having: obstructive nephropathy, bilateral nephropathy, hydronephrosis, reduced or non-function kidney, and/or atrophic kidney) who had 99m Tc-DMSA and 99m Tc-DTPA dynamic scintigraphies utilizing the same protocol. Results: A strong positive correlation had come in view on the evaluation of the left kidney, right kidney, and total glomerular filtration rate (GFR) from 99m Tc-DTPA and 99m Tc-DMSA renograms. In addition, the estimation of the time of the peak height from 99m Tc-DTPA and 99m Tc-DMSA renograms for the right and left kidneys demonstrated as non-significant varieties and a strong positive correlation for both the normal subjects and subjects with kidney abnormalities. Conclusion: In the light of the outcomes gained from the present investigation, it could be prescribed that 99m Tc-DMSA can favorably replace 99m Tc-DTPA in dynamic renograms in the case of the renal conditions that had been examined in the present work. As scheduled, this will be cost-effective and time saving and will decrease the radiation dose administered to the subjects. Also, the same qualities of results are accomplished with both radiopharmaceuticals in normal subjects and subjects with abnormal renal function.

In the present study, we investigated the radiation doses received by the positron emission tomography (PET)/computed tomography (CT) staff in three different diagnostic centers in Egypt. The whole-body effective dose measured by thermoluminescent dosimeters (TLDs) for staff working in PET and the effective dose per study received by physicist, technician, and nurse were measured by an electronic pocket dosimeter (EPD) during a period of 6 months. Statistical analysis was held between the measurements of the TLDs as well as for the EPD for the three studied PET-CT centers. After combining TLD and EPD prospective annual scores for the three studied categories in the three centers, the one-way ANOVA test results have shown that there were statistically significant differences between group means with respect to their TLD mean score ( P = 0.041). The mean nurse group TLD score, across the three centers, appeared to be the lowest scoring 3.83 (standard deviation [SD] 0.012) compared to the physicist and technician who measured 4.62 (SD 0.231) and 6.92 (SD 0.018), respectively. Scheffe's test for complex comparisons revealed a significant difference between nurse group and technologist group ( P = 0.001). Regarding the annual combined EPD scores, the post hoc test, namely Scheffe's test for complex comparisons, revealed a significant difference between nurse group and technologist group ( P = 0.001). This was measured after the one-way ANOVA test results have shown that there were statistically significant differences between annual group EPD means ( P = 0.032). Finally, there was no recorded significance for the studied categories across the three centers between their annual TLD and EPD dose scores ( P = 0.072). Technicians group received the highest mean effective whole-body doses when compared with the International Commission on Radiological Protection dose limit, each individual worker can work with many more 18F-fluorodeoxyglucose (FDG) PET/CT studies for a (period time) without exceeding the occupational dose limits if the average received effective dose continues with the same rate. The study also confirmed that low levels of radiation dose are received by medical personnel involved in 18F-FDG PET/CT procedures in those centers due to implementing radiation protection measures and procedures.

In the present study, we have investigated the finger radiation doses received by nuclear medicine staff involved in dispensing, administration of 18F-FDG and interacting with radioactive patients during imaging procedures in PET/ CT facility within three different diagnostic centers. Materials and methods: Using finger ring dosimeters delivered to physicists, technicians, and nurses, the readings were collected after one month of working. Each with his own assigned job task that varies according to the center's policy. Results: Finger doses were found to be within the permissible limits. The mean prospective annual finger dose measurements, across the three centers show that the physicist group has the highest received prospective annual dose 440.01 mSv/year. The mean technician's prospective annual finger dose measurements, across the three centers, appeared to be the lowest scoring 94.83 mSv/year and nurses measured 115.8 mSv/year. Finally, there was no recorded significance for the studied categories across the three centers between their prospective annual finger dose measurements. The highest finger dose was recorded for the physicists who are likely exposed from the handling of the 18F-FDG multi-dose syringe, transferring the dose to the injection room and measuring the postinjection residual dose in the syringe. The nurse performed shorter part with readymade individual radiopharmaceutical syringe and pre-intravenous time before and during administration. Also, the technicians spent the maximal time per study; however, they have the lowest finger dose because they are not exposed directly to handle the radioactive material.