pharm 2 chapter 93: drugs for UTIs

cystitis

bladder inflammation

localized infection

Symptoms: Dysuria, urinary urgency, urinary frequency, suprapubic discomfort, pyuria, bacteriuria (subclinical pyelonephritis)

• Single-dose therapy

• Short-course therapy (3 days)

• Conventional therapy (7 days)

UTIs

• second most common infection

• se*ually active young women

  • 25-35% develop at least 1 UTI a year

• older adult women in nursing homes

  • almost half have bacteria at any given times

• less frequent in males

  • occurrence likely associated with complications (sepsis, pyelonephritis)

complicated and uncomplicated UTIs

• upper —kidney

  • acute pyelonephritis

  • acute bacterial prostatitis

• lower —bladder and urethra

  • acute cystitis

  • acute urethral syndrome

• recurrent urinary tract infections

organisms that cause UTIs

• community acquired UTIs: E.coli

• hospital acquired UTIs: klebsiella, proteus, enterobacter, pseudomonas, staphylococci, enterococci, e.coli

• bacteria from the skin or rectum travel up the urethra to the bladder

drugs for UTIs

TMP/SMZ

penicillin

aminoglycosides

cephalosporins

fluoroquinolones

carbapenems

methanamine

acute uncomplicated pyelonephritis

• Common in young children, older adults, women of child-bearing age

  • Fever, chills, severe flank pain, dysuria, urinary frequency, urinary urgency, pyuria, and usually bacteriuria

• 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

Complicated UTI

• female and male patients with structural or functional abnormality of the urinary tract

  • prostatic hyperplasia, renal calculi, nephrocalcinosis, renal or bladder tumors, ureteric stricture, or indwelling catheter

• symptoms range from mild to severe

  • patient may develop systemic illness manifesting as fever, bacteremia, and septic shock

recurrent UTI

relapse

• recolonization with the original infecting organism

• suggests structural abnormality of urinary tract, involvement of kidneys, or chronic bacterial prostatitis

reinfection

• usually involves lower urinary tract and may be related to sexual intercourse

• main reason for reinfection in females

acute bacterial prostatitis

• Inflammation of the prostate caused by local bacterial infection

  • High fever, chills, malaise, myalgia, localized pain, dysuria, nocturia, 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

urinary tract antiseptics

nitrofurantoin and methenamine

Nitrofurantoin [Furadantin]Macrodantin, Macrobid] MOA

• Low concentrations: Bacteriostatic

• High concentrations: Bactericidal

Nitrofurantoin [Furadantin]Macrodantin, Macrobid] indications

• Lower UTIs, prophylaxis,

• recurrent lower UTIs

Nitrofurantoin [Furadantin]Macrodantin, Macrobid] adverse effects

Gastrointestinal effects

Pulmonary reactions: Acute and subacute( intresitila  lung disease)

Hematologic effects: cannot be used in kids younger than 1 month bc of risk of hemolytic anemia

Peripheral neuropathy: Demyelination and nerve degeneration can occur and may be irreversible

Hepatotoxicity

Birth defects- category B 

• can only be used if absolutely needed

Can cause fungal/superinfection with prolonged use

Nitrofurantoin [Furadantin]Macrodantin, Macrobid] contraindications

Contraindicated in children less than 1 month of age due to high risk of hemolytic anemia

Nitrofurantoin [Furadantin]Macrodantin, Macrobid] major points

can cause peripheral neuropathy

methenamine [Hiprex, Urex] MOA

decomposes into ammonia and formaldehyde, which denatures bacterial proteins

methenamine [Hiprex, Urex] indication

chronic lower UTIs (TMP/SMZ is the preferred drug)

methenamine [Hiprex, Urex] adverse effects

• relatively safe and generally well tolerated

• contraindicated in renal and liver failure

• steven johnson syndrome

methenamine [Hiprex, Urex] drug interactions

• urinary alkalinizers

• sulfonamides

methenamine [Hiprex, Urex] contraindications

renal and liver failure, contraindicated in children under 6

methenamine [Hiprex, Urex] nursing education

drink a lot of water, photosensitivity

TMP/SMZ MOA

Inhibits sequential steps in bacterial folic acid synthesis, making it much more powerful than TMP or SMZ alone

TMP/ SMZ indications

• UTI, otitis media, bronchitis, shigellosis, pneumonia caused by Pneumocystis jiroveci, Pneumocystis

• pneumonia, and GI infection

TMP/ SMZ adverse effects

• Gastrointestinal

  • Nausea and vomiting

•  Rash

•  Hyperkalemia

•  Hypersensitivity reactions (Stevens-Johnson syndrome)

• Blood dyscrasias (hemolytic anemia, agranulocytosis, leukopenia, thrombocytopenia, aplastic anemia) 

• Kernicterus (neonates!)

• Renal damage: Crystalluria

• CNS ( headaches, depression, hallucinations)

TMP/ SMZ interactions

• Warfarin, phenytoin, sulfonylurea-type oral hypoglycemic

  • Intensify the effects 

• Methotrexate 

  • Intensify bone marrow suppression 

• drugs that raise potassium levels can increase the risk for hyperkalemia from TMP.

TMP/ SMZ contraindications

pregnancy

TMP/ SMZ nursing mgmt

•  Inspect IV site frequently. Phlebitis is common.

• Assess client for allergy to sulfonamides.

• Monitor I&O. Promote adequate fluid intake.

•  Monitor BMs for signs of CDAD that can occur several wk after therapy has ended.

•  Monitor for rash development or DRESS, and, if noted, discontinue therapy.

•  Monitor CBC with diff, LFT, RFT.

TMP/ SMZ major points

• The patient needs to drink a lot of water

• Increased risk of kidney stones

• Photosensitivity- wear sun protection