Background & Objective: Tuberculosis is a diseases which is severely threatening the individuals health and is spreading quickly. Moreover, the appearance of new strains resistant to drugs has complicated the issue. Since there is no information available regarding the present drug-resistance situation of patients suffering from tuberculosis in Mashhad, this study was conducted to determine the prevalence of this resistance in this city.

 Methods: To determine prevalence of anti-tuberculosis drug resistance in Mashhad, drug sensitivity of 75 M. tuberculosis strains isolated from patients with pulmonary and extra-pulmonary tuberculosis from 20 Feb. 2002 to 20 Aug. 2002 was studied using the indirect proportion method. Every strain was tested against Rifampicin (RMP), Isoniazid (INH), Ethambutol (ETM), and Streptomycin (STM). Medical records of the patients were reviewed. Patients with no or less than 1 month treatment were defined as new cases and those previously treated for more than 1 month were defined as previously treated cases.

 Results: Of 75 isolates, 70(93.33%) were from new and 5(6.66%) from previously treated cases. 68 patients (90.66%) were suffering from pulmonary and 7(9.33%) from extra-pulmonary tuberculosis. Of 75 isolates, 23(36%) were resistant to at least one anti-tuberculosis drug. The highest rate of resistance was observed to streptomycin. Three of the 75 strains (4%) were resistant to all four drugs. 1.43% and 40% of strains isolated from newly and previously treated patients respectively were multidrug resistant.

 Conclusions: In this study new cases with MDR-TB were less prevalent compared to other studies. Most drug resistance and MDR-TB were associated with previous treatment. Continual evaluation of drug resistance following DOTS implementation seems to be necessary.

 Background & Objective: The emergence of multi-drug resistant salmonella strains h ave made t h e treatment of typhoid fever difficult all over the world. It is even more complicated w h en t h e hi g h cost of newly marketed antibiotics, their side effects and arising bacterial resistance to them are considered. Knowledge of antibiotic sensitivity and resistance of salmonella can make prevention of side-effects and emergence of resistance as well as the treatment measures more effective in this region.

  Methods : This descriptive study was performed in a 6-year period between 1992-97 on 397 patients who were culture positive (blood and stool) in terms of typhoid. The drug resistance was determined based on the anti-biogram of salmonella separated from blood and stool culture of the patients.

  Results: The total number of patients was 397 (237 males, 160 females). All of the subjects were above 12 years old. The resistance of strains of salmonella separated from the blood and stool culture to an antibiotic was 76.9 and 79.6 percent respectively. Resistance to ampicillin, amoxicillin, co-trimoxazole and chloramphenicol was highest among others. There were 60 strains with multi-drug resistance 34 of which (8.57% of all patients) were separated from blood culture and 26 (6.55% of all patients) from stool-culture. The amount of microorganisms multi-drug resistance separated from blood and stool was 6.55% and 8.57% respectively (15.12% in total).

  Conclusions : Using antibiotics without the knowledge of bacterial resistance and sensitivity can complicate the issue.

 Background & Objectives: Identifying urinary tract infection, especially in infants and young children is very important from the viewpoint of start of treatment, and if it is delayed probably the children are affected by risk of failure to thrive, sepsis and chronic problems such as renal scars, increase of arterial blood pressure and renal failure. Increasing usage of antibiotics, result in AB resistance microorganism. This study was done because of bacterial differences in resistance in different regions and the change in the rate of resistance in UTI.

 Methods:�This research is a descriptive-prospective study 510 children under the age of 12 as the study samples were chosen. These children were referred to clinics of Ardabil Aliasghar and Sabalan Hospitals in 2006. Their urine culture colony was above 100000. Data gathering was accomplished by their parents through questionnaire and interview's then gathered Data were analyzed by computer software programs of the SPSS and Excel.

 Results:�Findings of research showed that symptoms of malodorous urine (54.7%) in children under 12 months, dysuria (58.9%) in 1-3 years age groups, frequency (54.8%) in 3-6 years old groups dysuria (49.2%) in 6 years old groups and above were most prevalent symptoms which were reported. From the viewpoint of gender differences UTI in girls was 4 times more than that of boys that this difference in 1-3 years old groups was highest range (4.8 to 1). About antibiotical resistancy of microorganisms, Ampicillin with 78.9% resistance, Co-trimoxazole with 66%, Cephalexin with 62.8% and cephazoline with 33.3% were most resistant antibiotics respectively. E-coli resistance against gentamicine was 15.8%, that compared with other microorganisms is very high and its resistance against ceftriaxon was 8%, which is low compared with other microorganisms.

 Conclusion: Findings of research showed the variety of UTI symptoms in children and also showed that drug resistancy against Ampicillin, Co-trimoxazole, Cephalexin and cephazoline is high.