rostomy tubes. Patients with a solitary kidney, history of

renal transplant, or renal dysfunction should be discussed

with urology and admitted.

..... Discharge

Most patients with nephrolithiasis can be successfully

managed in the ED and safely discharged. They should

have adequate pain control and the ability to tolerate oral

NEPHROLITHIASIS

intake before discharge. Follow-up is recommended with

a primary care provider within 1 week for small ( <6 mm),

uncomplicated kidney stones in patients with a known

history of nephrolithiasis. Urology follow-up is recommended for patients with first time stones and large (>6

mrn) proximal stones, as these stones have a low likelihood ( < 1 Oo/o) of spontaneous passage. Patients should be

given prescriptions for opioid analgesics and a urine

strainer with instructions to strain all urine until stone

passage and to bring passed stones to their follow-up

appointment. Alpha blockers (tamulosin, terazosin, or

doxazosin) are prescribed for up to four weeks to relax

ureteral smooth muscles and increase the rate of stone

passage and decrease pain. Lastly, patients should be given

clear and specific discharge instructions to return to the

ED if they have fever, persistent vomiting, intractable pain,

or inability to urinate.

SUGGESTED READING

Manthey DE, Nicks BA. Urologic stone disease. I n: Tintinalli JE,

Stapczynsk.i JS, Ma OJ, Cline DM, Cydulka, RK, Meckler GD.

Tintinalli's Emergency Medicine: A Comprehensive Study

Guide. 7th ed. New York, NY: McGraw-Hill, 201 1 , 651-657.

Urinary Tract

Infections

Rebecca R. Roberts, MD

Key Points

• Differentiate a contami nated urinalysis from urinary

tract infection (UTI}. Obtain a catheterized urine

specimen when the diagnosis is in question.

• Send a urine culture only when appropriate

(pregnancy, recurrent UTI, pyeloneph ritis, urosepsis,

INTRODUCTION

A urinary tract infection (UTI) refers to an infection anywhere in the urinary system in the presence of bacteriuria

and symptoms. Cystitis is a lower tract infection of the

bladder. Pyelonephritis is an upper tract infection of the

kidney. An uncomplicated UTI occurs in patients without

comorbidities and with an anatomically and functionally

normal urinary tract. Complicated UTI occurs in patients

with a functional or anatomic abnormality of their urinary

tract or with the presence of serious comorbidities that

place the patient at risk for serious adverse outcomes.

These comorbidities include pregnancy, diabetes, immunocompromise, cancer, advanced age, and recent hospitalization or instrumentation. Anatomic factors that cause

obstruction of urine flow resulting in complicated UTI

include prostate enlargement, renal stones, obstructing

tumors, and ureteral reflux, compression, or stricture.

UTI is one of the most common bacterial infections.

In 2007, nearly 1 .7 million UTis were diagnosed in U.S.

emergency departments (EDs), and 12% required hospital admission. Neonates, girls, and young women are

at increased risk for infection. UTI is uncommon in

young men; however, men older than 55 years have an

increased risk due to incomplete bladder emptying from

prostatic hypertrophy. UTI is the leading cause of sepsis

immunosuppression, fever without a source, indwel ling

bladder catheter).