Urinary Tract Infection and Drug Susceptibility Pattern in Patients of a Medical College Hospital in Bangladesh

Background: Urinary tract infection (UTI) is a common and frequently encountered serious morbidity that afflicts the tool not only to all segments of human population but also results in increasing antibiotic resistance due to persistence and mismanagement of the ailment. The present study aimed to ascertain the current situation of antimicrobial resistance of urinary tract infection. Objectives: To find out pyuria by direct microscopy, isolation and identification of the organisms by culture and to know the susceptibility pattern of organisms causing urinary tract infection. Materials and Methods: A total of 180 midstream urine samples were subjected to aerobic bacteriologic culture in the department of Microbiology, Cox’s Bazar Medical College and 250-bedded Sadar Hospital, Cox’s Bazar during the period of March to October 2012. Specimens were collected from hospitalized and outdoor patients of different age and sex groups. All specimens were examined by routine microscopy to find out significant pyuria (>5 pus cells/HPF). Strict aseptic precautions were taken all through the culture system. Results: Out of 180 specimens, 101 (56.11%) culture yielded significant growth of single organism and 79 (43.89%) yielded no growth. The isolated organisms were E. coli 74.26%, Klebsiella species 12.87%, Enterococci 4.95%, Staphylococcus saprophyticus 3.96%, Pseudomonas species 1.98% and Proteus species 1.98%. The highest sensitivity was shown by imipenem (100%) followed by ceftriaxone (65%), azithromycin (65%), ciprofloxacin (60%) and less sensitive to amoxycillin, cotrimoxazole, cephradine and nalidixic acid ranging 15–30%. Conclusion: The findings of the present study recommends that UTI should be treated by selective antibiotics obtained from culture and sensitivity test to minimize increasing trend of drug resistance.

Urinary tract infection (UTI) is one of the most prevalent extraintestinal bacterial infections and it represents one of the most common diseases encountered in medical practice affecting people of all ages. 1 About 150 million people are diagnosed with UTI each year worldwide. 2Most infections are caused by retrograde ascent of bacteria from the fecal flora via the urethra to the bladder and kidney, especially in the females who have a shorter and wide urethra and more readily transfer microorganisms. 3Majority of the UTIs are not life threatening and do not cause any irreversible damage.However, when the kidneys are involved, there is a risk of irreparable tissue damage with an increased risk of bacteremia. 4 Introduction 21

Urinary Tract Infection and Drug Susceptibility Pattern in
Patients of a Medical College Hospital in Bangladesh commonest microorganism both in domiciliary and hospitalized patients.The other common pathogens are species of Klebsiella, Enterococcus, Pseudomonas, Proteus and Staphylococcus saprophyticus. 6e incidence of UTI is 20% greater in women as compared to men due to anatomical position. 5ow-a-days, drug resistance is a huge growing problem in treating infectious diseases like malaria, TB, diarrhoea, UTI etc.As suggested by Goldman & Huskins, the improper and uncontrolled use of antibiotics results in the emergence of antimicrobial resistance, which is a major health problem worldwide. 7,8Particularly in the developing world, apart from high level of poverty, ignorance and poor hygiene practices, there is also high availability of fake and spurious drugs. 8Studies aimed at gaining knowledge about the type of pathogens responsible for UTI and their susceptibility pattern may help the clinicians to choose the right empirical treatment.

Materials and Methods
The study was done in the Microbiology department of Cox's Bazar Medical College and 250-bedded Sadar Hospital, Cox's Bazar during the period March to October, 2012.For the purpose of this study 180 clean catch midstream urine (MSU) specimens were collected in sterile container for microscopy, culture and susceptibility test.Each sample was inoculated on both blood agar and MacConkey's agar media and incubated at 37 0 C for 24-48 hours within 1 hour after collection.Portions of the specimens were centrifuged at 3000 rpm for at least 3 minutes and centrifuged deposits were examined by direct microscopy to find out significant pyuria (>5 pus cells/HPF).Specimens showing growth were subjected for colony count according to standard method. 9Colony count >1×10 5 /mL of urine was considered as significant.The isolated bacteria were identified accordingly by colony morphology, Gram's staining, motility, appropriate biochemical test and direct agglutination test using known specific antisera.Antibiotic susceptibility tests were carried out on Mueller-Hinton agar plate by disk diffusion method.
Commercially available antibiotic discs were used.After overnight incubation, zones of inhibition were measured in mm and results were reported as sensitive and resistant as per standard chart.

Results
Out of 180 cases, 60 were in the age group of up to 12 years where 24 (40%) were male and 36 (60%) were female.Out of 120 cases in the age group of above 12 years 54 (45%) and 66 (55%) were male and female respectively.Total male were 78 (43.33%) and female were 102 (56.67%) giving a male to female ratio 1:1.3 (Table I).

Discussion
Antibiotic resistance of bacteria has been gradually becoming a major medical and public health problem.Injudicious use of antibiotics has resulted in emergence of many Gram positive and Gram negative resistant bacterial population.In this study 60 (33.33%) samples were from children (up to 12 years) and rest were from above 12 years age group.Female were predominating in both age group indicating that UTI is common in women which was supported by many authors. 6In this study significant pyuria and culture positivity was also higher in females.It is evident that E. coli was the predominant uropathogens (74.26%) causing UTI followed by Klebsiella species (12.87%),Enterococci species (4.95%), Staphylococcus saprophyticus (3.96%), Pseudomonas species (1.98%) and Proteus species (1.98%).Staphy-lococcus saprophyticus, Pseudomonas species and Proteus species were also the less frequent agents causing UTI in another study. 10The percentage of resistance of E. coli to the antimicrobial agents were 82.67% to cotrimoxazole, 80% to amoxycillin, 74.67% to cephradine and 69.33% to nalidixic acid.The percentages of resistance of pathogens varied between 100% and 20% to antimicrobial agents while susceptibility of the pathogens varied between 100% and 17.33%.In this study, all types of bacterial isolates were 100% susceptible to imipenem.A significant increase in resistance of pathogenic strains to cotrimoxazole, amoxycillin, nalidixic acid and cephradine has been found worldwide. 11The overall rate of resistance to cotrimoxazole found in this study was significantly higher than those reported by others. 12For the past decades, cotrimoxazole or trimethoprim alone has been used widely as an empirical therapy for UTI caused by E. coli.The results of this study indicate that ciprofloxacin resistance was slightly higher than that reported in previous studies. 13A decline in the activity of ciprofloxacin would be especially problematic in view of the ability of Gram negative bacilli to acquire resistance to all other classes of antimicrobials. 14Our study shows that resistance to ciprofloxacin continues to increase.If urgent measures are not taken to control the situation, we may see the return of the era of the search for new drugs to fight bacterial infections.According to Mandal et al 15 E. coli was the commonest cause of UTI and antibiotic resistance was high among the strains.The practices of self medication, drug abuse and indiscriminate use of antibiotics among the general population certainly will favor the emergence and propagation of resistant strains in future.

Table I :
Age and sex distribution of study population

Table IV :
Antibiotic susceptibility pattern of isolated uropathogens 23