Microbiology UTI 1 Hani Masaadeh Hadeel Al-Momani 1 Page #1
Date :27/4/2016 Lecture#1 Micro Lecture#21 UGS Subject : UTI *Urinary tract is normally sterile due to the fact that bacteria moving upwards are regularly washed out by urination ( first line defense mechanism). * Normal flora found in the urethra consist of lactobacillus (in Female ) and staphylococcus in few number (if the colonies exceed certain number = UTI). * UTI is Second most common infection following respiratory infections. *UTI occur when bacteria (E. coli) from the digestive tract( anus ) get into the opening of the urinary tract and multiply.. especially in female.. why? bcz of anatomical structure >> short distance between the anus and the urinary tract opening & the urethra is shorter in female also. * urethra >> bladder >> ureters >> Kidneys. * UTI tend to occur more in women than men.. WHY? :\ UTI Upper *Pyelonephritis is an inflammation of the kidney tissue, calyces, and renal pelvis. Pyelonephritis * Cystitis is the medical term for inflammation of the bladder. *Upper urinary system (Kidneys, Ureters ) Lower *Cystitis * Urethritis * Prostatitis "male" *Lower urinary system (Bladder, Male urethra,female urethra ) *Urethritis (often sexually-transmitted) "imp". ***General Symptoms of Urinary Tract Infection: 1- Dysuria 2- Increased Frequency 3- Hematuria"severe cases " 4- Fever "Pyelonephritis" 5Nausea \ Vomiting "Pyelonephritis " 6- Flank Pain "Pyelonephritis " >>> INFormation is HDFna :P. HDFna = Our Goal in Arabic " for Malaysians ". * Upper Infection is MORE SEVERE than lower infections. 2 Page
Physical Exam: 1- Costovertebral angle( CVA) tenderness (pyelonephritis). 2- Urethral discharge (urethritis), usually the color of discharge is Yellow!. 3- Tender prostate on digital rectal examination( DRE) (prostatitis). Labs: Urinalysis: 1- leukocyte esterase (+ve in UTI ) 2- nitrites ( +ve in UTI ).. When? & Why? This test is commonly used in diagnosing urinary tract infections (UTI). A positive nitrite test indicates that the cause of the UTI is a gram negative organism, most commonly Escherich ia coli. The reason for nitrites' existence in the presence of a UTI is due to a bacterial conversion of endogenous nitrates(no 3) to nitrites(no-2). More likely gram-negative rods 3- WBCs ( +ve in UTI ) >> Netrophils " bacterial infection.. most common, in some cases fungal infection " 4- RBCs ( +ve in Severe Cases & in female more ). Culture in UTI : *Positive Urine Culture = >105 CFU/mL >> CFU stands for Colony Forming Unit.. *Most common pathogen for cystitis, prostatitis, pyelonephritis: Escherichia coli (most common ), Staphylococcus saprophyticus, Proteus mirabilis, Proteus Vulgaris, Klebsiella, Enterococcus " group D only.. expected Q " Group D has two type : one Entrococcus, one not Entrococcus >> Entrococcus cause these diseases. KPPSEE >> اﻟﻜﺒﺴﺔ ﺑﺘﻌﻤﻞ ﻛﻞ ھﺎذ it s a joke *Most common pathogen for urethritis : Chlamydia trachomatis, Neisseria Gonorrhea.. " sexually transmitted " DO you remember? CYstitis Three Types : 1-Uncomplicated (Simple) cystitis : In healthy woman, with no signs of systemic disease. 2- Complicated cystitis : In men, or woman with comorbid medical problems "we have sign ". 3 Page
3-Recurrent cystitis : occur frequently ; No enough treatment lead to Recurrent cystitis. Let's talk about the types in more details : Uncomplicated Cystitis : 4 Page
Complicated Cystitis : 5 Page
Recurrent Cystitis : *Want to make sure urine culture and sensitivity obtained. *May consider urologic work-up to evaluate for anatomical abnormality. *Treat for 7-14 days. Pyelonephritis Infection of the kidney ( from lower urinary tract or hematogenus Associated with constitutional symptoms (fever, nausea, vomiting, headache)>> Symptoms of septicemia. **Diagnosis: Urinalysis, urine culture, CBC, Chemistry **Treatment: (2-weeks) of Trimethroprim/sulfamethoxazole or fluoroquinolone Hospitalization and IV antibiotics if patient unable to take po (PO= per os, Latin word means orally ). **Complications: 1- Perinephric/Renal abscess: Suspect in patient who is not improving on antibiotic therapy. Diagnosis: CT with contrast, renal ultrasound May need surgical drainage. 2- Nephrolithiasis with UTI : Suspect in patient with severe flank pain Need urology consult for treatment of kidney stone. 6 Page
Prostatitis ** in males more than 50 years old. **Symptoms: Pain in the perineum, lower abdomen, testicles, penis, and with ejaculation, bladder irritation, bladder outlet obstruction, and sometimes blood in the semen **Diagnosis: ~Typical clinical history (fevers, chills, dysuria, malaise, myalgias, pelvic/perineal pain, cloudy urine) ~The finding of an edematous and tender prostate on physical examination ~Will have an increased PSA ~Urinalysis, urine culture **Treatment: Trimethoprim/sulfamethoxazole, fluroquinolone or other broad spectrum antibiotic, 4-6 weeks of treatment **Risk Factors: Trauma, Sexual abstinence, Dehydration. 7 Page
AETIOLOGY 1. Bacterial infections of urinary tract are a very common reason to seek health services 2. Common in young females and uncommon in males under age 50 3. Common causative organisms : Escherichia coli (gram-negative enteral bacteria) causes most community acquired infections>> MOST COMMON CAUSE. Staphylococcus saprophyticus, gram-positive organism causes 10 15% Catheter-associated UTI s caused by gram-negative bacteria: Proteus, Klebsiella, Seratia, Pseudomonas. Before taking the sample we should tell the patient how get the specimen? first of all, the patient should take a lot of water & solutes, after that the patient should urinate out of the container sterile container then we take the sample, mid stain urine, after few urination we tell the patient to put few amount of urine into container ( screw cap container )اﻟﻐﻄﺎء ﺑﻠﻒ ﻟﻒ then we sent the sample to the lab quickly to prevent the contamination or bacteria multiplication >> the # of bacteria affect the diagnosis. CLINICAL PRESENTATION Cystitis : 1-dysuria (burning or discomfort on urination). 2- frequency. 3- nocturia is a condition in which you wake up during the night because you have to urinate. 4-suprapubic discomfort. *Urine is sterile (I didn t understand this!) * Presence of inflammatory cells or pathogens in urine indicate * a urinary tract infection (UTI) managed in general medical practice * Up to 50% of women will have a UTI at some point in their life 8 Page
* UTI uncommon in men except over the age of 60 when urinary tract obstruction due to prostatic hypertrophy may occur Urinary System Infections: Serious problem in hospitals Cause morbidity Pathogens can travel up the ureters and reach the kidneys UTIs are named according the place of infection In the urethra = Urethritis In the bladder = Cystitis In the kidneys = Nephritis/ Pyelonephritis In the prostate (men) = Prostatitis *Majority of infections are caused by bacteria, though some are fungal Urine is an excellent culture medium for bacteria Bacteria entering the bladder from the external environment or blood passing through the renal artery can normally be flushed out during urination Infections occur when bacteria get into the urine and remain More easily in women because of a shorter urethra and absence of bacteriostatic prostatic secretions (as in men) Catheterisation may also introduce organisms into the bladder 9 Page
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PATHOGENESIS: *bacteria get access from urethra and ascends *Females are more prone due to: 1- small urethra 2- gram negative organism radiate from peri anal area to urethra 3- sexual intercourse 4- susceptibility of epithelium *Female sex and intercourse predisposes *Pregnancy: ureteral tone and urethral peristalsis decreases *Obstruction in free flow of urine: tumor, stricture, calculi and bph etc. *Catheterisation, urethral dilatation, cystoscopy The normal bladder is capable of clearing itself of organisms within 2 to 3 days of their introduction. 11 P a g e
Defense mechanisms : (1) the elimination of bacteria by voiding (2) the antibacterial properties of urine and its constituents (3) the intrinsic mucosal bladder defense mechanisms (4) an acid vaginal environment (female) (5) prostatic secretions (male) Two potential routes : (1) the hematogenous route, with seeding of the kidney during the course of bacteremia (2) the ascending route, from the urethra to the bladder, then from the bladder to the kidneys via the ureters. Hematogenous Infection Because the kidneys receive 20% to 25% of the cardiac output, any microorganism that reaches the bloodstream can be delivered to the kidneys. The major causes of hematogenous infection are S. aureus, Salmonella species, P. aeruginosa, and Candida species. Chronic infections (skin, respiratory tract) >> blood circulation >> kidney (cortex) >> small abscess >> renal tubular >>renal pelvis >> renal papillary Ascending Infection The ability of host defense >>Urinary tract mucosal cells damaged >>The power of bacterial adhesions(toxicity) organisms >> urethra,periurethral tissues >> bladder >> ureters >> renal pelvis >> renal medulla. AND IT'S DONE All slides are included (1-34).. DONE BY : Hadeel Izzat Al-Momani. ذاﻫﺒ ﺔ ﺑﺬ ا ﱃ ﻣﲀن.. ﲻﻠﺖ ﻪ ﯾﻮﻣ ﺎ و.. ﻬ ﺮ ﻗﻠﺐ ﳗﺮ رﻏﺐ! ﻫﻞ ﱄ ﺑﺬ ﻫﻞ ﱄ ﺑﺬ.. ﻟﺰ ﻻل و ﺳﲈ ء ﺑﻌﯿﺪ ة وﻗﻠﱯ و ر ﰻ ﳾء..! ﺑﻮ ﲬﺲ دﻗﺎﯾﻖ ﺑﺘﻜﻮن اﳋﺰا ت ﻓﺎﺿﺖ و ﲆ ﺷﻼل ﻟﻌﯿﻮﻧﻚ.. اﻟﺴﲈء ﺑﻌﯿﺪة و رﺑﻚ ﻣﻮﺟﻮد و راﱖ ﺷﻐ ﻞ اﳌﺎﺗﻮر.. اﻃﻠﻌﻲ ﲆ اﻟﺴﻄﻮح.. ﺑﺬ ﺧ ﺎﻩ! ﺩﻣﺘﻢ ﺑ ﻮﺩ 12 P a g e ﻧﻌﻢ -