UTI in Adults and Children
( Lecture # 5 )URINARY TRACT INFECTION IN ADULTS
Incidence UTI (urinary tract infection) - common, affecting all ages and both sexes the most common but one infections (the first - breath infections) Clinical syndromes associated with UTI: septicaemia (urosepsis) renal infection pyelonephritis pyonephrosis renal abscess peri- et paranephric abscessURINARY TRACT INFECTION IN ADULTS cont. … cystitis - bacterial, abacterial prostatitis urethritis epididymitis, epididymo-orchitis
Methods of introducing UTI
Ascending infection - via urethra to bladder, reflux of infected urine up to ureter and/or spread of organisms along peri-ureteric lymphatics infection via a fistula (e.g. vesico-colic) heamatogenous infection (via renal artery)Aetiology and pathogenesis
the urinary tract is normally sterile above the distal urethra the chiefly defence mechanisms: hydrokinetic = the dilution of bacteria by the flow of urine mucosal = mainly secretion of immunoglobulin A (Ig A) and phagocytic capability of the urothelium itselfFactors predisposing to infection
UTI - commoner in women: due to shorter urethra opening of urethra at the vaginal vestibule, which is readily contaminated with faecal organism in many young women, infection are precipitated by sexual intercourse, bacteria-laden secretion from the perineum entering the urethra during sexual activity (so called honey- moon cystitis) In either sex UTI may develop: Incomplete bladder emptying (residual urine) due to outflow obstruction (BPH, urethral stricture … )Factors predisposing to infection cont. … Bladder diverticula Neuropathic bladder Upper urinary tract stasis due to obstruction of ureter, megaureter, stones Vesico-ureteric reflux interferes with both ureteric and bladder emptying and is commonly accompanied by infection
Factors predisposing to infection cont. … Calculi, bladder tumours and foreign bodies (e. g. catheters) are predispose to infection, as may instrumentation of the urinary tract Factors that suppress the immune response (diabetes mellitus, cytotoxic or immunosuppressive agents)
Common urinary pathogens
I. Ascending infection Bacteria Gram-negative - Escherichia coli - klebsiella spp proteus spp - pseudomonas spp Gram-positive cocci - streptococcus faecalis - staphylococcus aureus chlamydia trachomatis L-organism - ureaplasma urealyticum, mycoplasma hominis Fungi - candida sppCommon urinary pathogens cont. … II. Haematogenous infection Bacteria - mycobacterium tuberculosis Fungi Parasites - schistosoma spp Viruses - cytomegalovirus, adenovirus type 11
Clinical manifestation
Symptoms Lower UTI Voiding symptoms - frequency, urgency, micturition with discomfort, burning sensation (= dysuria) Occasionally haematuria Upper UTI loin pain Systemic disturbance - fever, sweating, rigors Some patients have lower UTI as well (often upper UTI follow lower UTI) Physical signs Fever and tachycardia Tenderness in the loin and in the suprapubic regionClinical manifestation cont. … Diagnosis the presence of pus cells on microscopy the presence of significant number (over 10 5 per ml) of organism in a mid-stream specimen of urine (MSU) microbiology laboratories determines antibiotic sensitivities specialised microbiological techniques may be required in certain circumstances (e. g. Tuberculosis, fungal infection, viral infection)
Clinical manifestation cont. … Further investigation Cystitis in young sexually active women investigation is not required for the first attack unless it is accompanied by haematuria or loin pain investigation is indicated in this group of women for recurrent infections, in older women, pregnant women, children, men, diabetes mellitus, neuropathy, known urinary stones or urinary tract anomaly - urinary tract ultrasound, if indicated IVU, blood count, the serum urea and creatinine
Clinical manifestation cont. … Treatment Antibiotics commonly used to treat UTI : Nitrofurantoin Co-trimoxazol (sulfamethoxazol + trimethoprim) and trimethoprim alone Ampicillin, amoxycillin, co-amoxycillin (clavulic acid + amoxicillin) Gentamicin Quinolones (norfloxacin, ciprofloxcin)
Treatment cont. … Cefalosporins High fluid intake and regular emptying of the bladder to promote hydrostatic clearance of bacteria Attention to personal hygiene for women with recurrent infection In patients with collections of infected urine or pus (e.g. pyonephrosis, perinephric abscess) drainage is usually required
UPPER URINARY TRACT INFECTIONS
Acute renal infection Most result from ascending infection (75% of patients have preceding lower-tract symptoms) Some they are result of haematogenous spread There is important to distinguish between infection alone and infection combined with upper-tract obstruction; the latter combination may lead to rapid obstruction of renal tissue unless prompt drainage of the obstructed kidney is establishedPathology
Acute pyelonephritis Acute inflammation of the pelvic epithelium, with bacteria entering the collecting duct and fornices to produce inflammation of the renal parenchyma Renal carbuncle An abscess in the renal parenchyma and is usually due to haematogenous spread of organisms (Typically staph. aureus from foil, infected infusion site, contaminated needles in drug addicts)Pathology cont. … Pyonephrosis Infection within an obstructed kidney rapid destruction of kidney Perinephric abscess It result form any of the above infective processes Initially the infection is confined by Gerota’s fascia (= perinephric abscess), but may rupture through this (= paranephric abscess) and to reach the skin (in Petit’s lumber triangle) , the psoas muscle or the bowel; it may even rupture through the diaphragm to reach the pleura and lungs
Pathology cont. … Clinical symptoms Loin pain, fever, tachycardia, scoliosis in sever cases Mass may be palpable in the loin Septicaemia and shock Investigation Urine should be examined for pus cells and bacteria (urine culture), blood culture (all patients with pyrexia or clinical suspicious of septicaemia) Ultrasound urinary tract, liver, spleen, a plain abdominal X-ray, chest X-ray, IVU
Management
Septicaemic patient rapid intravenous fluid replacement intravenous hydrocortisone or methylprednisolone parenteral bactericid antibiotics Subsequent management depend on the pattern of infection, basic treatment is are antibiotics .Management cont. … Acute pyelonephritis antibiotics for 7-14 days, guided by the result of urine culture and sensitivity Renal carbuncle drainage by aspiration of the abscess under ultrasound or CT control by open surgery
Management cont. … Pyonephrosis Drainage by percutaneous nephrostomy or with a ureteric catheter passed retrogradely from the bladder at cystoscopy After improvement ascendant pyelography or descendent pyelography (nephrostogram) identification of obstruction renal scintigraphy determines remaining renal function
Management cont. … treatment of obstruction (e. g. ureteroscopy for ureterolithiasis, nephrectomy if kidney function is by scintigraphy under 10 (15) %) Perinephric abscess surgical drainage or nephrectomy, if function in the affected kidney is very poor
Chronic pyelonephritis
combination of renal scarring and urinary infection it may follow vesico-ureteric reflux and infection repeated episodes of acute pyelonephritis differential diagnosis of other types of interstitial nephritis or hypoplasia of kidney is difficult Treatment Eradication of infection to prevent further renal damage. Nephrectomy, if: renal function is under 10 (15) % sever secondary hypertensionXantogranulomatous pyelonephritis
The result of granulomatous reaction within kidney to chronic infection Treatment nephrectomyLOWER URINARY TRACT INFECTIONS
Acute bacterial cystitis usually result of ascending bacterial infection from the perineum particularly common in women (due to short urethra) Clinical features: Frequency and urgency of micturition with dysuria There may be suprapubic pain, urine often has a fishy smell or may be blood stained = haemorrhagic cystitis) Association of loin pain and fever suggest spread of infection to the kidney (acute pyelonephritis)LOWER URINARY TRACT INFECTIONS cont. …