UTI - Genitourinary Tract Infections PDF

Genitourinary Tract Infections Wijini Wijayabandara (BSc. Biomedical Science; MSc. Molecular Life Sciences) Genitourinary tract defences 2  UTIs Urinary tract infection (UTI) is an infection in any part of the urinary syst...

Genitourinary Tract Infections Wijini Wijayabandara (BSc. Biomedical Science; MSc. Molecular Life Sciences) Genitourinary tract defences 2  UTIs Urinary tract infection (UTI) is an infection in any part of the urinary system The urinary system includes the kidneys, ureters, bladder and urethra UTIs are more common in females because their urethras are shorter and closer to the rectum this makes it easier for the bacteria to enter the urinary tract 3  Pathogen and pathophysiology When bacteria enter the urinary tract and multiply, they can cause a UTI To infect the urinary system, a micro-organism usually has to enter through the urethra or, rarely, through the bloodstream The most common bacterium to cause UTIs is Escherichia coli (E. coli) It is usually spread to the urethra from the anus 4 TYPES OF UTIs urethritis — infection of the urethra cystitis — infection of the bladder pyelonephritis — infection of the kidneys vaginitis — infection of the vagina. 5  RISK FACTORS Women - sexually active women are vulnerable, in part because the urethra is only four centimeters long and bacteria have only this short distance to travel from the outside to the inside of the bladder People with urinary catheters - such as people who are critically ill, who can't empty their own bladder People with diabetes - changes to the immune system make a person with diabetes more vulnerable to infection Men with prostate problems - such as an enlarged prostate gland that can cause the bladder to only partially empty Babies - especially those born with physical problems (congenital abnormalities) of the urinary system 6 SYMPTOMS 7 Treatment Bacterial vaginitis Metronidazole Clindamycin Urethritis : Azithromycin Doxycycline 8 Prevention 9  Gonorrhea Gonorrhea has been known as a sexually transmitted disease Neisseria gonorrhoeae, also known as the gonococcus, is the causative agent In the male, infection of the urethra elicits urethritis, painful urination and a yellowish discharge Relatively large number of cases are asymptomatic In the female a mucopurulent (containing mucus and pus) or bloody vaginal discharge occurs in about half of the cases, along with painful urination if the urethra is affected Children born to gonococcus carriers are also in danger of being infected as they pass through the birth canal 10  Gonorrhea N. gonorrhoeae is a pyogenic, gram-negative diplococcus. It appears as pairs of kidney bean–shaped bacteria Gonococci use specific chemicals on the tips of fimbriae to anchor themselves to mucosal epithelial cells The gonococcus also possesses an enzyme called IgA protease, which can cleave IgA molecules stationed for protection on mucosal surfaces N. gonorrhoeae does not survive more than 1 or 2 hours on objects/materials and is most infectious when transferred to a suitable mucous membrane The best method for diagnosis is a PCR test of secretions Currently, no vaccine is available for gonorrhea, using condoms is an effective way to avoid transmission of this and other discharge diseases Treatment : ceftriaxone + azithromycin or doxycycline 11 Syphilis A common infectious conditions can result in lesions on a person’s genitals Caused by Treponema pallidum, a spirochete, is a thin, regularly coiled cell with a gram- negative cell wall Untreated syphilis is marked by distinct clinical stages designated as primary, secondary, and tertiary syphilis The spirochete appears in the lesions and blood during the primary and secondary stages and, thus, is transmissible at these times Syphilis is largely nontransmissible during the tertiary stages 12  Syphilis Brought into direct contact with mucous membranes T. pallidum binds by its hooked tip to the epithelium At the binding site, the spirochete multiplies and penetrates the capillaries nearby Within a short time, it moves into the circulation T. pallidum produces no toxins and does not appear to kill cells directly The specific factor that accounts for the virulence of the syphilis spirochete appears to be outer membrane lipoproteins These molecules appear to stimulate a strong inflammatory response, which is helpful in clearing the organism 14 Diagnosis 15 Risk factors/ prevention /Treatment 16 Fungus infection 17 Fungus infection 21 Candidiasis 23  Candidiasis Epidemiology Oral candidiasis is the most common fungal infection of the mouth, and it also represents the most common opportunistic oral infection in humans In the Western Hemisphere, about 75% of females are affected at some time in their lives with a vaginal yeast infection Oesophageal candidiasis is the most common Oesophageal infection in persons with AIDS Candida is the fourth most common cause of bloodstream infections among hospital patients in the United States (Nosocomial infection) 24  Pathophysiology Colonization entails superficial adherence and proliferation of Candida on the mucosa Defences against colonization include normal salivation, a healthy epithelium, and a balance between oral bacterial and fungal flora Fungal virulence factors includes the ability to colonize and adhere to mucosa by undergoing morphogenesis to the hyphal form or ability to secrete proteinases to lyse host cell membranes. Primary or acquired immunodeficiency leads to impaired defences against Candida Broad-spectrum antibiotics may eliminate certain bacteria that inhibit fungal growth, thereby enhancing Candida overgrowth 25 Vaginitis 26 Risk factors 27 Signs and symptoms 28 Sample collection 29  Laboratory diagnosis of Candida albicans Specimen: It is according to the site of the lesion i.e. exudates, vaginal, oral swab, tissue, nail scrap, blood. 1. Microscopic Examination 1. Stained smears: Gram stain, yeast cells are seen as Gram positive, oval budding yeast cells attached to pseudohyphae. 2. 40% KOH: budding yeast, pseudohyphae The presence of pseudohyphae in the smear is a clear indication that the yeast is growing rapidly and causing a yeast infection 30 Laboratory diagnosis of Candida albicans 1. Culture: Grow on Sabouraud's dextrose agar (SDA) at 37 °C Sabouraud Dextrose Agar (SDA) is a medium for the isolation of pathogenic and non-pathogenic fungi microorganisms (molds and yeasts) This agar is naturally acidic which inhibits the growth of many bacteria. Identification of candida on the plate is done by: 1. Morphology: grows in thick, curd-like colonies 2. Gram stain: Gram positive oval budding yeast cells 31 Laboratory diagnosis of Candida albicans Biochemical reactions: To differentiate between Candida albicans and other species. 1. Germ tube test: Candida albicans forms germ tube when incubated in serum for l — 2 hour at 37 °C 1. Sugar fermentation: Candida albicans ferment glucose and maltose with acid and gas production 2. Inoculation of the yeast on chromogenic agar: Each candida species produces a different color on this medium 32 Laboratory diagnosis of Candida albicans GET: Germ tube test: a) Inoculate 3ml of horse serum & incubate for 2-3 hrs. b) Put drop of preparation on slide & screen with 10X , 40X for tube like structure i.e. germ tube. GTT positive > production of germ tubes in plasma after 3 hours incubation at 37°C. → C. albicans. Germ tube negative > Budding blastoconidia only are seen → other Candida species 33  Treatment Nystatin and miconazole are the most commonly used topical antifungal drugs Topical alternatives for oral candidiasis are amphotericin B, fluconazole or clotrimazole 34 THANK YOU Affiliated with Durdans Hospital 35