TABLE OF CONTENTS
DECLARATION ii
CERTIFICATION iii
DEDICATION iv
ACKNOWLEDGEMENTS v
TABLE OF CONTENTS vi
LIST OF TABLES x
LIST OF PLATES xi
ABSTRACT xii
CHAPTER ONE 1
INTRODUCTION 1
1.1 Background of the Study 1
1.2 Statement of the Problem 5
1.3 Aim and Objectives of the Study 6
1.3.1 Aim 6
1.3.2 Specific objectives 6
1.3 Justification 6
CHAPTER TWO 8
LITERATURE REVIEW 8
2.1 Emergence of Antimicrobial Resistance and their Impact on Healthcare Delivery 8
2.2 Prevalence of Urinary Tract Infection in West Africa and Nigeria 8
2.3 Epidemiology of UTI 9
2.3.1 Aetiology 10
2.3.2 Bacterial UTI 11
2.3.3 Fungal & Viral Urinary Tract Infection 12
2.4 Modes of bacterial entry 13
2.4.1 The ascending route 13
2.4.2 Haematogenous route 13
2.5 Pathogenesis of UTI 13
2.5.1 Bladder Emptying 14
2.6 Clinical Manifestations of Urinary tract infections 15
2.6.1 Asymptomatic bacteriuria 15
2.6.1 Cystitis 16
2.6.2 Acute Pyelonephritis 16
2.7 Laboratory Diagnosis of Urinary Tract Infections 17
2.7.1 Automated and Semiautomated Systems 18
2.7.2 Molecular Identification of Uropathogens 19
2.8 Urine collection 20
2.9 Treatment of UTIs 21
2.10 Antimicrobial Resistance of Uropathogen 23
2.10.1 Factors Influencing Resistance of Antibiotics 25
2.11 Mechanisms of Action of Antimicrobial Agents 27
2.12 Prevention of UTI and control 28
CHAPTER THREE 30
MATERIALS AND METHODS 30
3.1 Study population 30
3.2 Sample collection 30
3.3 Materials 31
3.4 Microscopy Examination 31
3.5 Isolation and Identification of Microorganisms 32
3.6 Biochemical Identification of Isolates 32
3.6.1 Catalase Test 32
3.6.2 Coagulase Test 32
3.6.3 Oxidase Test 33
3.6.4 Triple Sugar Iron (TSI) Agar Test 33
3.6.5 Indole Test 33
3.6.6 Motility Test 34
3.6.7 Citrate Test 34
3.6.8 Urease Test 34
3.7 Antibiotic Susceptibility Testing 35
3.8 Data Management and Analysis 36
CHAPTER FOUR 37
RESULTS AND DISCUSSIONS 37
4.1 Prevalence of Uropathogens 37
4.2 Identification of Uropathogens Isolated using Biochemical Tests 37
4.3 Antimicrobial Susceptibility of Bacterial Uropathogens 40
CHAPTER FIVE 57
CONCLUSIONS AND RECOMMEDATIONS 57
5.1 Conclusions 57
5.2 Recommendations 57
5.3 Suggestion for Further Studies 58
LIST OF TABLES
Table 3.1: Standard Antimicrobial Inhibition Zones According to Clinical Laboratory Standards Institute (CLSI) 36
Table 4.1: Isolates from the study population (n=50) 38
Table 4.2: Biochemical results for Gram negative isolates 39
Table 4.3: Biochemical results for Gram positive isolates 40
Table 4.4: Antimicrobial Susceptibility Profile of Gram- negative Uropathogens isolated from Urine Culture for asymptomatic female students of Akwa Ibom State University (n-19) (Source: Researcher, 2019) 49
Table 4.5: Antimicrobial susceptibility pattern Gram positive uropathogens isolated from urine culture for asymptomatic female students of Akwa Ibom State University (n=9) (Source: Researcher, 2019) 51
Table 4.6: Resistance pattern of bacterial isolates to more than two antibiotics of asymptomatic female students of Akwa Ibom State University (N = 28) (Source: Researcher, 2019) 52
LIST OF PLATES
Plate 4.1: Measuring of diameters of zone of inhibition using veneer caliber 50
ABSTRACT
CHAPTER ONE
INTRODUCTION
1.1 Background of the Study
Urinary tract infection (UTIs) are the inflammatory disorders of the urinary tract caused by the abnormal growth of pathogens (Prakash and Saxena, 2013, Amaliet al., 2009) Urinary tract infection is known to cause short-term morbidity in term of fever, dysuria, and lower abdominal pain (LAP) and may result in permanent scarring of the kidney (Hobermanet al., 2003, Camacho et al., 2004). Urinary tract infection can be community acquired or nosocomial. Community-acquired urinary tract infection (CA-UTIs) are defined as the infection of the urinary system that takes place in one’s life in the community setting or in the hospital environment with less than 48 hours of admission. Community-acquired UTI is the second most commonly encountered microbial infection in the community setting (Sabrina, 2010).
Usually UTIs are caused by single type of organism though polymicrobic infections are found in complicated cases with urinary stones and anatomical abnormality of urinary tract. Presence of 105cfu/ml in midstream urine is considered as significant number of bacteria for UTI (Kass, 2015) though this number is fewer for asymptomatic patients and patients using antimicrobials, consuming large amount of liquid, with urinary obstruction and pyelonephritis acquired from hematogenous spread. UTI is the most common nosocomial infection (Mark and Gordon, 1994) and remarkable differences on type of infecting organisms are evident in community acquired and hospitalized cases (Calvin, 1994). UTIs are more common in women than in men though male over 60 years with prostatic hypertrophy are the exceptions (Calvin, 1994; Jawetz et al., 2005).Women are more prone to UTIs than men because in females, the urethra is much shorter and closer to the anus than in males (Jawetz and Melnick et al., 2005) and they lack the bacteriostatic properties of prostatic secretions. The female genital tract is closely related to the bladder and this relationship makes the spread of diseases possible from one tract to the other (Epstein, 2010). Therapeutic decision should be based on accurate, up-todate anti-microbial susceptibility pattern. Interim data have been published from a European multi-centre survey that examined the prevalence and antimicrobial susceptibility of community acquired pathogens causing uncomplicated UTI in women (Kahlmeter, 2000). The duration of treatment for adult has received much attention. Traditionally, a course of 7-10 days has been advocated, still this is the recommendation for treating men. For women, though, there has been particular emphasis on the suitability of short-course regimens such as 3-days or even single-dose therapy. The consensus of an international expert working group was that 3-day regimens are as effective as longer regimens in the cases of trimethoprim and quinolones. β-Lactams have been inadequately investigated on this point but short courses are generally less effective than trimethoprim and quinolones and Erythromycin require further study before conclusion can be drawn (Warren et al., 2009). Patients with pyelonephritis may be severely ill and if so, will require admission to hospital and initial treatment with a parenteral antibiotic. A first choice agent would be parenteral cefuroxime, gentamycin or ciprofloxacin. When the patient is improving, the route of administration may be switched to oral therapy, typically using a quinolone. Conventionally, treatment is continued for 10-14 days. Patients who are less severely ill at the outset may be treated with an oral antibiotic, and possibly with a shorter course of treatment. The safety of this approach has been demonstrated in a study of adult women with acute uncomplicated pyelonephritis (Talan et al., 2000). In hospital acquired pyelonephritis, there is a risk that the infecting organism may be resistant to the usual first-line drugs. In such cases it may be advisable to start a broad spectrum agent such as ceftazidime, ciprofloxacin or meropenem. In a study of women with catheter-associated infection, asymptomatic bacteriuria resolved spontaneously within 2 weeks in only 15 of 42 patients (Godfrey et al., 2011). However, those with persistent and symptomatic bacteriuria responded well to single-dose treatment. Several different types of novel catheters with antiinfective properties have been developed with the aim of reducing the ability of bacteria to adhere to the material, which should lead to a decreased incidence of bacteriuria and symptomatic infection. Several studies of the effect of incorporating antibiotics such as rifampicin and minocycline (Darouchie et al., 2009) or silver based alloys (Newton et al., 2002) into the catheter have shown benefit. Although clearly more costly than standard catheters, economic evaluation shows silver alloy catheters to be cost effective when used in patients needing catheterization for several days (Plowman et al., 2001). The prevalence of asymptomatic bacteriuria of pregnancy is approximately 5%, about a third of these women proceed to develop acute pyelonephritis, with its attendant consequences for the health of both mother and pregnancy. Furthermore, there is evidence that asymptomatic bacteriuria is associated with low birth weight, pre-maturity, hypertension and pre-eclampsia. For these reasons it is recommended that screening is carried out, preferably by culture of a properly taken MSU, which should be repeated if positive for confirmation (National Collaborating Centre for Women’s and Children’s Health 2003). Rigorous meta-analysis of published trials (Smaill, 2000) has shown that antibiotic treatment of bacteriuria in pregnancy is effective at clearing bacteriuria, reducing the incidence of pyelonephritis and reducing the risk of preterm delivery. The following measures may reduce the incidence of urinary tract infections. These may be appropriate for people, especially women, with recurrent infections (Mayon-White et al., 1988; Fisher et al., 2005; Talukder et al., 2017). Such as avoiding the delay of urination, cleaning the urethral opening with an antiseptic after intercourse, fruit juice (cranberry, blueberries) containing tannins can decrease the incidence of UTI, tannins prevent the adherence of certain pathogens (E. coli) to the epithelium of the urinary bladder, intravaginal application of topical estrogen cream and long courses of low-dose antibiotics taken at night can prevent recurrent cystitis, breast feeding can reduce the risk of UTIs in infants. In children, recurrence of UTI is a common and the complications potentially hazardous, so many clinicians recommended anti-microbial prophylaxis following documented infection. The evidence in favor of this practice is not strong (Le Saux et al., 2000), and although it has been shown to reduce the incidence of UTI, it has not been shown to reduce the incidence of renal complications. Indiscriminate use of antibiotics and other related factors are responsible for the evolution of many drug resistant microbial strains causing infections including UTI. Moreover, the ever changing pattern of sensitivity indicates the importance of continuous investigation for updating relevant data for intended use as guidelines for appropriate treatment by the physicians. And hence the present study was undertaken to find out the most frequent microbial cause of UTI and the patterns of their sensitivity to different antibiotics in order to facilitate better treatment and management of UTIs.
Generally, there is agreement among the various authors in the literature that the predominant uropathogens acquired from any source are Gram negative bacteria with Escherichia coli accounting for the highest prevalence in most instances (Gupta et al 2009, Huda et al 2003, Moges et al 2002) Gram positive organisms including Enterococcus spp and coagulase negative staphylococci are also frequently involved (Moges et al 2002). Antibiotic resistance of urinary tract pathogens has been known to increase worldwide, especially to commonly used antimicrobials. (Gordon et al 2000, Gupta et al 2009, Kahlmeter 2003, Mazzuli 2002). The antibiotic sensitivity patterns of either one or more of the organisms have been determined to one or more of the commonly used antimicrobial drugs in Urinary Tract Infection (UTI) cases (Gordon et al 2000, Gupta et al 2009, Huda et al 2003, Kahlmeter 2003). There is need therefore to evaluate the activity of newer antibiotics against the organisms so as to determine the best option in therapy and to monitor incidence of resistance.
1.2 Statement of the Problem
UTIs are a major complication of diabetes, real disease, renal transplantation, and structural and neurologic abnormalities that inter fare with urine flow. A major challenge in recent times is the abuse of antimicrobials which poses a major public health problems leading to the emergence and reemergence of resistant strains. The problem is particularly health-care providers, unskilled practitioners and patients are common. Bacterial resistant to most antibiotic is a global public health concern leading to treatment failure, high cost of treatment, increased morbidity and mortality. However, this is more of a problem in sub-Saharan Africa where bacterial infection is very common, and knowledge on antibiotic resistance pattern is very limited. Most patients with suspected UTI, out of frustration, visit local chemical stores often run by untrained personnel to buy antibiotics without any prescriptions, leading to antibiotic resistance and treatment failure. Also due to the complexity and time it takes to undertake a bacterial culture and susceptibility laboratory test, doctors mostly start patients with a broad spectrum antibiotics before the lab results are out. Although this is aim at early treatment to alleviate the pain and anguish associated with UTI, it is also a primary contributor to the development of antibiotic resistance. In view of the above limitations, this study envisaged to add to the knowledge base on the bacteria causing UTI and their antibiotic susceptibility pattern, and to assess, if there is any, its predominance in asymptomatic female than the male.
1.3 Aim and Objectives of the Study
1.3.1 Aim
The aim of this study is to investigate the level of carriage of common urinary pathogens by healthy female students of Akwa Ibom State University, their virulence potentials and their antibiotics resistance rates.
1.3.2 Specific objectives
Specific objectives will include;
To collect urine samples from asymptomatic female students of Akwa Ibom State University, Ikot Akpaden using the midstream technique
To isolate uropathogens from asymptomatic female students of Akwa Ibom State University, Ikot Akpaden using standard bacteriological methods
To identify and determine the most common uropathogens isolated from asymptomatic female students of Akwa Ibom State University, Ikot Akpaden using standard bacteriological methods
To determine the antibiotic susceptibility profile/pattern of antibiotic-resistant uropathogens isolated and identified in asymptomatic female students of Akwa Ibom State University, Ikot Akpaden, Mkpat Enin L.G.A..
.
1.3 Justification
Conventional Antibiotics are preferred first line agents in the treatment of UTI because of their high bacteriological and clinical cure rates, when hypersensitivity is of concern, or where conventional agents are less desirable due to toxicity (Kamberiet al., 2009). Hence, increased pressure or overuse of any type of flouroquinolone could lead to emergence of resistance to an entire class. Nigeria, as some other Sub-Saharan African countries, has a very high prevalence of bacterial infections, and treatment of these infections is generally very poor due to poor health care delivery facilities and minimal training on proper management of infectious diseases. Most cases of uncomplicated UTIs can be mild and transient, hence correct and timely diagnosis of UTI is imperative. Antibiotic resistance is a global challenge as it is on increase from one geographical area to another. With widespread reports fluoroquinolone resistance, it is prudent that the sensitivity pattern of prevailing uropathogens is periodically assed. The would ensure that empirical treatment of UTIs with fluoroquinolones is based on evidence from local susceptibility and resistance data.
