Ch 89 - Drug Therapy of Urinary Tract Infections

Urinary Tract Infections (UTIs) - Upper (kidney)

- Acute pyelonephritis - Acute bacterial prostatitis

Methenamine [Mandelamine] - Therapeutic uses

- Chronic lower UTIs (TMP/SMZ is the preferred drug)

Acute Uncomplicated Pyelonephritis (kidney infection)

- Common in young children, older adults, women of child-bearing age - Fever, chills, severe flank pain (discomfort in your upper abdomen or back and sides), dysuria(discomfort urinating), urinary frequency, urinary urgency, pyuria (puss in the urine), and usually bacteriuria (bacteria in the urine) - E. coli = Causative organism in 90% of community-acquired infections - Mild pyelonephritis = Moderate infection (treatment at home with oral antibiotics) - Severe pyelonephritis = Requires hospitalization and IV antibiotics

Acute Cystitis - symptoms

- Dysuria (discomfort when urinating) - urinary urgency - urinary frequency - suprapubic discomfort = pain in your lower abdomen near where your hips and many organs (intestines, bladder, and genitals) are located - pyuria = puss in the urine - bacteriuria (subclinical pyelonephritis) = bacteria in the urine

Complicated UTI

- Female and male patients with structural or functional abnormality of the urinary tract - Prostatic hyperplasia (prostate gland enlargement), renal calculi (kidney stones), nephrocalcinosis (calcium levels in the kidneys are increased), renal or bladder tumors, ureteric stricture (narrowing of the ureter), or indwelling catheter - Symptoms range from mild to severe - Patient may develop systemic (over the body) illness manifesting as fever, bacteremia (bacteria in the blood), and septic shock

Nitrofurantoin [Furadantin] - Adverse effects

- Gastrointestinal effects - nausea, vomiting and diarrhea - Acute Pulmonary reactions = COMMON - dyspena (shortness of breath), chest pain, chills, fever, cough, and alveolar infiltrates - Acute Pulmonary reactions = RARE - occur during prolonged treatment (dyspena, cough, malaise) - Hematologic effects - Peripheral neuropathy = Demyelinization and nerve degeneration can occur and may be irreversible - Hepatotoxicity - RARE - causes liver injury = undergo periodic test - Birth defects - a lot is unknown, best to use other things during pregnancy - CNS effects = headache, vertigo, drowsiness, nystagumus (vision condition)

Therapy of Urinary Tract Infections

- SECOND most common infection - Sexually active young women - 25% to 35% develop at least one UTI a year - Older adult women in nursing homes - 30% to 50% have bacteria at any given time - Less frequent in males - when women wipe it can get to their system easier - Occurrence likely associated with complications (septicemia, pyelonephritis)

Urinary Tract Infections (UTIs) - Complicated and uncomplicated UTIs

- Uncomplicated UTI = infection in a healthy, non-pregnant, pre-menopausal female patient with anatomically and functionally normal urinary tract. - Complicated UTI = infection associated with factors increasing colonization and decreasing efficacy of therapy.

Acute Cystitis - Conventional therapy (5-7 days)

- for all who do not meet criteria for short course = males, children, pregnant women, and women with suspected upper tract involvement - Nitrofurrantoin is 2 times a day for 5 days

Acute Cystitis - Short-course therapy (3 days)

- more effective than single dose therapy = generally preferred - advantages over conventional is lower cost, greater adherence, fewer side effects, and less potential for resistant bacterial emergence to form - Trimethoprim/sulfamethoxazole is taken for 3 days - twice a day

Urinary Tract Infections (UTIs) - Recurrent urinary tract infections

- relapse or reinfection of the bacteria - Relapse = recolonization of SAME orgainism - reinfection = colonization of NEW organism

The nurse is working with a patient who has a UTI. Because patient adherence to a medication regimen is a concern, the nurse anticipates use of which medication? a- Fosfomycin b- Amoxicillin c- Cephalexin d- Trimethoprim

a- Fosfomycin When adherence is a concern, fosfomycin, which requires just one dose, is an attractive choice. As a rule, amoxicillin and cephalexin are avoided, because they are less effective than the alternatives and are less well tolerated. Trimethoprim requires a longer course of therapy than fosfomycin.

The nurse identifies which statements about frequent urinary tract reinfections as true? (Select all that apply.) a- Reinfections are considered frequent if the individual has three or more a year. b- Prophylactic therapy should continue for at least 2 months. c- If reinfection is associated with sexual intercourse, the risk can be reduced by instructing the patient to void after intercourse. d- Single-dose nitrofurantoin 50 mg taken 1 hour before intercourse has been found to reduce the rate of reinfection. e- If a symptomatic episode occurs, the standard therapy for acute cystitis should be used.

a- Reinfections are considered frequent if the individual has three or more a year. c- If reinfection is associated with sexual intercourse, the risk can be reduced by instructing the patient to void after intercourse. e- If a symptomatic episode occurs, the standard therapy for acute cystitis should be used. Prophylactic therapy should continue for at least 6 months. Single-dose trimethoprim/sulfamethoxazole, taken after intercourse, has been found to reduce the risk of reinfection. The other three statements are true.

Most cases (more than 80%) of uncomplicated, community-acquired urinary tract infection (UTI) are caused by which bacteria? a- Klebsiella pneumoniae b- Escherichia coli c-Enterobacter spp. d- Pseudomonas spp.

b- Escherichia coli Most cases of uncomplicated, community-acquired UTI are caused by E. coli. In rare cases, other gram-negative bacilli (eg, K. pneumoniae, Enterobacter spp., and Pseudomonas spp.) are the cause.

A patient who has acute cystitis is receiving treatment with trimethoprim/sulfamethoxazole. Which manifestation should indicate to a nurse that the patient's condition is worsening? a- Klebsiella pneumoniae b- Flank pain c -3+ pedal edema d- Hyperactive bowel sounds

b- Flank pain Flank pain may indicate continued infection or pyelonephritis. When acute cystitis is treated with a traditional agent of choice, such as trimethoprim/sulfamethoxazole, manifestations of dysuria, urinary urgency and frequency, suprapubic discomfort, and bacteriuria improve. Incontinence, 3+ pedal edema, and hyperactive bowel sounds are unrelated to acute cystitis.

A nurse assesses the history of a patient who has had multiple complicated UTIs for which risk factors? (Select all that apply.) a- Female gender, child-bearing age b- Indwelling catheter c- Prostate hypertrophy d- Fair skin tone e- Urinary tract stones

b- Indwelling catheter c- Prostate hypertrophy e- Urinary tract stones Complicated UTIs occur in males and females and usually are associated with some predisposing factor, such as calculi, prostatic hypertrophy, or catheters. Uncomplicated UTIs occur primarily in women of child-bearing age and are not associated with any specific predisposing factor. Fair skin tone is unrelated to UTI occurrence.

The nurse is aware that acute cystitis occurs most often in which patient population? a- Older-adult male patients b- Children younger than 12 years c- Women of child-bearing age d- Women older than 50 years

c- Women of child-bearing age Acute cystitis is a lower urinary tract infection that occurs most often in women of child-bearing age.

A patient is to begin taking nitrofurantoin [Macrodantin]. The nurse should teach the patient that which manifestation should be the priority to report to the healthcare provider? a- Headache and drowsiness b- Brown-colored urine c- Nausea and vomiting d- Muscle weakness and tingling

d- Muscle weakness and tingling Nitrofurantoin is used in acute infections of the lower urinary tract only. Muscle weakness and tingling may indicate irreversible damage to sensory and motor nerves caused by demyelinization of nerves. Patients should be informed of these symptoms and taught to report them immediately. Gastrointestinal (GI) effects may be minimized by taking the drug with milk or food. Brown urine is a harmless effect of the urinary excretion of the medication. Headache and drowsiness are less common adverse effects that are readily reversible.

Nitrofurantoin [Furadantin, Macrodantin, Macrobid]

- Low concentrations = Bacteriostatic (stops bacteria from reproducing not killing otherwise) - High concentrations = Bactericidal (kills the bacteria) - Uses = Lower UTIs, prophylaxis (action taken to prevent disease), recurrent lower UTIs

Urinary Tract Antiseptics

- Nitrofurantoin - Methenamine

Methenamine [Mandelamine] - Adverse effects

- Relatively safe and generally well tolerated - Contraindicated in renal and liver failure

Organisms That Cause UTIs

- 80% of uncomplicated, community-acquired UTIs = Escherichia coli MAIN CAUSE - Hospital-acquired UTIs = Frequently caused by Klebsiella, Proteus, Enterobacter, Pseudomonas, staphylococci, enterococci, and E. coli

Urinary Tract Infections (UTIs) - Lower (bladder and urethra)

- Acute cystitis - Acute urethral syndrome

Acute Bacterial Prostatitis

- Inflammation of the prostate caused by local bacterial infection - High fever, chills, malaise (general feeling of discomfort), myalgia (muscle ache and pain), localized pain, dysuria (discomfort when urinating), nocturia (need to go to the bathroom excessively at night), urinary urgency, urinary frequency, urinary retention - 80% of cases caused by E. coli - Frequently associated with indwelling urethral catheter, urethral instrumentation, transurethral prostatic resection - Responds well to antimicrobial therapy

Which patient would most likely need intravenous antibiotic therapy to treat a urinary tract infection? A.A patient with an uncomplicated urinary tract infection caused by Escherichia coli B.A patient with pyelonephritis with symptoms of high fever, chills, and severe flank pain C.A patient with acute cystitis who complains of dysuria, frequency, and urgency D.A patient with acute bacterial prostatitis with a mild fever, chills, and nocturia

B Severe pyelonephritis requires intravenous antibiotic therapy.

Which patient does the nurse identify as most likely to need treatment with trimethoprim/sulfamethoxazole [Bactrim] for a period of 6 months? A.A female patient with acute pyelonephritis B.A male patient with acute prostatitis C.A female patient with recurring acute urinary tract infections A male patient with acute cystitis

C Female patients with relapses of urinary tract infection may need long-term therapy up to 6 months with trimethoprim/sulfamethoxazole

Which drug does the nurse identify as a urinary tract antiseptic? A.Ciprofloxacin B.Ceftriaxone C.Nitrofurantoin Ceftazidime

C Two urinary tract antiseptics currently are available: nitrofurantoin and methenamine. Ciprofloxacin, ceftriaxone, and ceftazidime are antimicrobials.

Methenamine [Mandelamine]

- Decomposes into ammonia and formaldehyde, which denature bacterial proteins - to release urine must be 5.5 or less - can not cause systemic toxicity

Recurrent UTI

Relapse - 20% recolonization with the original infecting organism - Suggests structural abnormality of urinary tract, involvement of kidneys, or chronic bacterial prostatitis Reinfection - 80% of recurrent UTIs in females - Usually involves lower urinary tract and may be related to sexual intercourse

With the exception of pyelonephritis, the nurse is aware that most urinary tract infections are treated by which method? a- IV antibiotics at the hospital b- IV antibiotics in the urgent care setting c- IM antibiotics at the primary physician's office d- Oral antibiotics in the home setting

d- Oral antibiotics in the home setting Except for pyelonephritis, most UTIs can be treated with oral therapy at home.

Methenamine [Mandelamine] - drug interatcions

- Urinary alkalinizers - Sulfonamides

Drug Therapy of UTIs

- Trimethoprim/sulfamethoxazole (TMP/SMZ) and nitrofurantoin = Frequently the treatment of choice for oral therapy of UTIs (FIRST LINE)

Acute Cystitis - Single-dose therapy

- for uncomplicated, community associated, non pregnant women who have had symptoms less than 7 days - Fosfomycin is the 1 day dose = good when worried of patient adherence

Which outcomes should a nurse establish when planning care for a patient taking methenamine [Mandelamine]? (Select all that apply.) a- Maintains a urine pH of 5.5 or lower. b- Consumes 3000 mL of liquid daily. c- Uses an enteric-coated formulation. d- Avoids sulfonamide medications. e- No elevation in liver enzymes.

a- Maintains a urine pH of 5.5 or lower. c- Uses an enteric-coated formulation. d- Avoids sulfonamide medications. Under acidic conditions, methenamine makes formaldehyde, which causes bacterial cell death. Formaldehyde requires an acid urine to be released. To prevent the dose from being converted to formaldehyde in an acidic stomach, an enteric-coated formula may be used. Ingestion of large volumes of fluid dilutes methenamine and raises the urinary pH. Hepatotoxicity is not associated with methenamine [Mandelamine].

A patient is taking nitrofurantoin [Macrodantin]. Which finding should a nurse recognize as an indication that the treatment is having an undesired effect? a- Hyperpigmentation of the palms b- Dyspnea with chills c- Gum irritation with bleeding d- Scalp tenderness and thinning hair

b- Dyspnea with chills Nitrofurantoin, a urinary tract antiseptic, may induce a pulmonary reaction that manifests with dyspnea, chest pain, and chills. These symptoms, which resolve 2 to 4 days after the drug is stopped, are thought to be hypersensitivity reactions. Hyperpigmentation of the palms, gum irritation with bleeding, and scalp tenderness and thinning hair are not side effects associated with nitrofurantoin.