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598 SECTION 10: Renal and Genitourinary Disorders  HEMATOSPERMIA Hemospermia, or hematospermia, is a disturbing symptom that produces extreme anxiety in sexually active males. 66 The incidence and prevalence of this condition are not known. Most symptomatic men seek medical attention after one or two occurrences. Any process that results in trauma or other injury (e.g., tumor with erosion), inflammation, or infection of the male ejaculatory system may result in bloody semen. 67 It is not uncommon after vigorous sexual activity. Unless the cause can be determined on physical exam, the diagnosis cannot be completed in the ED. Spontaneous resolution occurs in 89% of patients; however, median symptom duration is 6 weeks. 68 Hematospermia should be differenti ated from hematuria based on a clean-catch urinalysis (see Chapter 91, “Urinary Tract Infections and Hematuria”). Infection, including sexually transmitted infections, should be considered, and if suspected based on history and physical, the patient should be cultured and treated appro priately. Although all patients with hematospermia should be referred to a urologist, those >40 years old are at higher risk for cancer and should be strongly advised to seek further evaluation by a urologist even when there is spontaneous resolution of hematospermia. REFERENCES The complete reference list is available online at www.TintinalliEM.com. Urologic Stone Disease David E. Manthey Bret A. Nicks INTRODUCTION AND EPIDEMIOLOGY Emergency medicine management is directed at relieving pain, assessing kidney function, and determining the likelihood of spontaneous stone passage. This chapter discusses renal and ureteral stones. Bladder stones are discussed in Chapter 92, “ Acute Urinary Retention. ” Renal stones in children are discussed in Chapter 133, “ Acute Abdominal Pain in Infants and Children. ” The prevalence of kidney stones in the United States has risen from 5.2% in 1994 1 to 8.8% in 2010. 2 The prevalence is 10.6% in men and 7.1% in women. 2 Increasing prevalence is also documented in Europe and Southeast Asia. 3 Obesity and diabetes are strongly associated with kidney stones.2 For first-time stone formers, recurrence rates at 2, 5, 10, and 15 years are 11%, 20%, 31%, and 39%, respectively.4 PATHOPHYSIOLOGY Stone formation requires supersaturation of dissolved salts in the urine, which condense into a solid phase. Increasing the amount of solvent (urine) and decreasing the amount of solute presented to the kidney (i.e., calcium, oxalate, uric acid) can aid in prevention. Inhibitory substances, such as citrate, and magnesium can prevent crystal precipitation and stone formation. About 80% of calculi are composed of calcium oxalate, calcium phosphate, or a combination of both. Calcium excretion is elevated in conditions that include hyperparathyroidism, absorptive and renal hypercalciuria, and immobilization syndrome. Complex interactions between the gut, kidney, and bones contribute to calcium oxalate stone formation. A diet restricting calcium paradoxically increases calcium stone formation because there is less calcium to bind oxalate in the intestinal lumen, leading to increased absorption of oxalate from the gut, recruitment of calcium from bones, osteoporosis, and symptomatic stone disease in predisposed patients.

ne formation. A diet restricting calcium paradoxically increases calcium stone formation because there is less calcium to bind oxalate in the intestinal lumen, leading to increased absorption of oxalate from the gut, recruitment of calcium from bones, osteoporosis, and symptomatic stone disease in predisposed patients. CHAPTER TABLE 94-1 Kidney Stone Risk Factors Risk Factor Mechanisms Obesity May promote hypercalciuria Low urine volume Allows solute to supersaturate Excess dietary meat (purine) Creates acidic urinary milieu; depletes available citrate (inhibitor); promotes hyperuricosuria Excess dietary sodium Promotes hypercalciuria Insulin resistance, metabolic syndrome Ammonia mishandling; alters pH of urine Family history Genetic predisposition Gout Promotes hyperuricosuria Bowel surgery, inflammatory bowel disease Promotes low urine volume; acidic urine depletes available citrate (inhibitor); hyperoxaluria Primary hyperparathyroidism Creates persistent hypercalciuria Prolonged immobilization Bone turnover creates hypercalciuria Medications Indinavir, ephedrine, loop diuretics, topiramate, acyclovir, triamterene About 10% of stones are struvite (magnesium-ammoniumphosphate), which are found most commonly in women with recurrent urinary tract infections. These stones are associated with infection by urea-splitting bacteria (Proteus, Klebsiella, Staphylococcus species, Providencia, and Corynebacterium) and are the most common cause of stag horn calculi, which are large stones that form a cast of the renal pelvis. Antibiotic penetration into staghorn calculi is poor, and the potential for urosepsis exists as long as the stones remain. Uric acid causes about 10% of urolithiasis, occurs more commonly in men, and is associated with gout or chemotherapy. Urate stones are radiolucent, and the urine is typically acidic. Cystine stones account for approximately 1% of all stones and occur in patients with cystinuria, an autosomal recessive genetic disorder affecting amino acid transport (COLA: cysteine, ornithine, lysine, arginine). Some medications predispose to stone disease. The protease inhibi tor indinavir sulfate, used to treat the human immunodeficiency virus, is associated with a 4% to 10% incidence of symptomatic urolithiasis. Pure indinavir stones are radiolucent on plain abdominal radiograph and CT scan. Carbonic anhydrase inhibitors, triamterene, and laxative abuse also increase the prevalence of renal stones. 5 With appropriate evaluation, 90% of patients will have a cause identified, and over 50% of calcium oxalate stone recurrences can be prevented. 6 Table 94-1 lists risk factors associated with kidney stones.2,3,7 Pain associated with kidney stones is due to obstruction of a hollow viscus organ (ureter) and subsequent hydronephrosis creating pressure against Gerota’s fascia, causing flank pain. Isolated small renal pelvis stones (not staghorn) do not cause pain unless they cause intermittent obstruction of the entrance to the ureter. A migrating but nonobstruc tive stone also causes pain. During acute obstruction, most patients have no rise in serum creatinine because the unobstructed kidney functions at up to 185% of its baseline capacity. A rise in serum cre atinine in acute obstruction suggests a solitary kidney or preexisting renal disease such that the unobstructed kidney is unable to compensate completely. Fortunately, most patients have incomplete ureteral obstruction, and many patients can be safely observed over weeks. Irreversible renal damage from an obstructive kidney stone is rare if obstruction has been present for ≤1 month. The probability of spontaneous passage of stones is determined by multiple factors, including size, shape, location, and degree of ureteral obstruction.

, and many patients can be safely observed over weeks. Irreversible renal damage from an obstructive kidney stone is rare if obstruction has been present for ≤1 month. The probability of spontaneous passage of stones is determined by multiple factors, including size, shape, location, and degree of ureteral obstruction. Bizarre or irregularly shaped stones with spicules or sharp edges have a lower spontaneous passage rate. With complete obstruc tion, there is a lower rate of spontaneous passage than if the blockage is partial. The most common sites of obstruction include the uretero pelvic junction, where the 1-cm pelvis constricts into the 2- to 3-mm ureter; the pelvic brim, where the ureter courses over both the pelvis and the iliac vessels; and finally, the ureterovesical junction, because Tintinalli_Sec10_p0563-0606.indd 598 8/2/19 6:55 PM

e most common sites of obstruction include the uretero pelvic junction, where the 1-cm pelvis constricts into the 2- to 3-mm ureter; the pelvic brim, where the ureter courses over both the pelvis and the iliac vessels; and finally, the ureterovesical junction, because Tintinalli_Sec10_p0563-0606.indd 598 8/2/19 6:55 PM CHAPTER 94: Urologic Stone Disease 599 TABLE 94-2 Risk Factors for Poor Outcome With Stones Renal function at risk •  Diabetes •  Hypertension •  Renal  insufficiency •  Single  kidney •  Horseshoe  kidney •  Transplanted  kidney History of difficulty with stones •  Extractions •  Stents •  Ureterostomy  tubes •  Lithotripsy Symptoms of infection •  Fever •  Hypotension •  Systemic  illness •  Urinary  tract infection this is the most constricted site of the ureter due to the muscular coat of the bladder. Based on stone size alone, 98% of stones <5 mm will pass within 4 weeks without intervention. Sixty percent of stones 5 to 7 mm and 39% of stones >7 mm will pass within 4 weeks. Stone size on plain radiographs is magnified by up to 20%, and a measured stone on CT is 88% of actual stone size. CLINICAL FEATURES The classic symptom complex for nephrolithiasis is the acute onset of a crampy intermittent flank pain that radiates toward the groin. As pain originates from a hollow viscus (ureter), the pain is visceral in nature without associated peritoneal irritation. Patients writhe in pain, unable to find a position of comfort. However, patients with renal colic may demonstrate rebound abdominal tenderness (29%), guarding (61%), and rigidity (8%). 10 Pain is commonly accompanied by nausea and vomiting (50%).10 The adrenergic response to pain can result in tachycardia, hypertension, and diaphoresis. Hematuria is present in only 85% of patients with renal colic, and 30% have gross hematuria.10 The location of the pain correlates somewhat with the location of the stone. Stones in the upper ureter refer pain to the flank, whereas those in the mid-ureter radiate to the lower anterior quadrant of the abdo men. A distal ureter stone, which is where 75% of stones are diagnosed, refers pain to the groin. Stones positioned at the ureterovesical junction can mimic a urinary tract infection by causing frequency, urgency, and dysuria in 3% to 24% of patients. 10 Extracorporeal shock wave lithotripsy fractures stones into small particles with the use of focused sound waves. The resulting “sludge” is passed in the urine. When there are large fragments, an acute episode of renal colic occurs. During the patient interview, elucidate four important items of history: assess risk factors for stone development (Table 94-1), prior stone-related outcome, history of renal disease, and important mim ickers. The risk factors for a poor outcome with stones include three categories: renal function at risk, history of difficulty with stones, and infection ( Table 94-2). Two mimickers that are very important to exclude are abdominal aortic aneurysm and renal artery infarction. Nephrolithiasis is the most common misdiagnosis given to patients with a rupturing or expanding abdominal aortic aneurysm. Recall that stones do not usually present in men older than age 60 without a prior history of nephrolithiasis and do not cause hypotension, even transiently. Renal artery thrombosis can mimic stone symptoms due to swelling of the infarcted kidney and can also be associated with hematuria. If the patient is pregnant, consider ectopic pregnancy in the differential diagnosis. DIAGNOSIS The diagnosis of urologic stone disease is clinically suspected and supported by the presence of hematuria; imaging confirms the diagnosis with certainty. Many diagnoses can be confused with renal colic ( Table 94-3).

turia. If the patient is pregnant, consider ectopic pregnancy in the differential diagnosis. DIAGNOSIS The diagnosis of urologic stone disease is clinically suspected and supported by the presence of hematuria; imaging confirms the diagnosis with certainty. Many diagnoses can be confused with renal colic ( Table 94-3). History and physical examination can be difficult because the patient’s discomfort may interfere with adequate information collection. The most critical diagnoses to consider are aortic dissection and ruptured abdominal aortic aneurysm. Renal colic and abdominal aortic aneurysm may have similar presentations.  LABORATORY EVALUATION The laboratory evaluation centers on evaluating for infection, kidney dysfunction, and possibility of pregnancy. Test all females of childbearing potential for pregnancy when considering renal colic, to help direct imaging and to exclude ectopic pregnancy. Urinalysis is needed to rule out infection. If infection is found, obtain urine culture and sensitivities to guide antibiotic therapy. 11 A urine culture should be done on all patients with sterile pyuria as renal colic patients with pyuria have 36% positive cultures as compared to those without pyuria (3.3%). 12 In suspected pediatric nephrolithiasis, urine culture is routine (see Chapter 135, “Urinary Tract Infection in Infants and Children”). TABLE 94-3 Differential Diagnoses for Ureterolithiasis Vascular Aortic dissection Abdominal aortic aneurysm Renal artery embolism Renal vein thrombosis Mesenteric ischemia Renal Pyelonephritis Papillary necrosis Renal cell carcinoma Renal infarct Renal hemorrhage Ureter Blood clot Stricture Tumor (primary or metastatic) Bladder Tumor Cystitis GI Biliary colic Pancreatitis Perforated peptic ulcer disease Appendicitis Inguinal hernia Diverticulitis Cancer Bowel obstruction Gynecologic Ectopic pregnancy Pelvic inflammatory disease/tubo-ovarian abscess Ovarian cyst Ovarian torsion Endometriosis GU Testicular torsion Epididymitis Other Drug-seeking behavior Shingles Retroperitoneal hematoma/abscess/tumor Tintinalli_Sec10_p0563-0606.indd 599 8/2/19 6:55 PM

rticulitis Cancer Bowel obstruction Gynecologic Ectopic pregnancy Pelvic inflammatory disease/tubo-ovarian abscess Ovarian cyst Ovarian torsion Endometriosis GU Testicular torsion Epididymitis Other Drug-seeking behavior Shingles Retroperitoneal hematoma/abscess/tumor Tintinalli_Sec10_p0563-0606.indd 599 8/2/19 6:55 PM 600 SECTION 10: Renal and Genitourinary Disorders TABLE 94-4 Ancillary Tests in Urologic Stone Disease Test Sensitivity (%) Specificity (%) LR+ LR– Comments Noncontrast CT 94–97 96–99 24–∞ 0.02–0.04 Advantages: speed, no RCM, detects other diagnoses Disadvantages: radiation, no evaluation of renal function US 63–85 79–100 10–∞ 0.10–0.34 Advantages: pregnancy, no RCM, no radiation, no known side effects Disadvantages: insensitive in middle third of the ureter, may miss smaller stones (<5 mm) Plain abdominal radiograph 29–58 69–74 1.9–2.0 0.58–0.64 Advantage: may be used to follow stones Disadvantage: poor sensitivity and specificity Abbreviations: LR = likelihood ratio; RCM = radiocontrast media. FIGURE 94-1. A. Arrow shows 6-mm stone within the proximal third of the left ureter on noncontrast CT reformatted image of upright abdomen. B. From same patient as in A, note 6-mm stone (arrow) within the proximal third of the left ureter on noncontrast CT. A B Hematuria (three or more red blood cells per high-power field) , or even its absence, can mislead the physician. Although 10% to 15% of patients with nephrolithiasis will have no hematuria, approximately 24% of patients with flank pain and hematuria have no radiographic evidence of ureterolithiasis . 13 Therefore, although hematuria may contribute to diagnostic decision making, it should not be used alone to exclude or confirm the diagnosis of ureterolithiasis 13 (see Chapter 91, “Urinary Tract Infections and Hematuria”). Check renal function because the overwhelming majority of patients who form stones have reduced creatinine clearance. 14 A WBC count does not aid in the evaluation because many patients will have an ele vated WBC count due to stress demargination. Other laboratory studies, such as serum calcium or uric acid, are not useful in the initial evalua tion or treatment but help determine stone type and long-term therapy.  IMAGING Imaging confirms the presence of a ureteral stone, rules out other diagnoses, identifies complications, defines stone location, and assists with management if the stone fails to pass spontaneously. 15 Imaging is recommended by the American Urological Association in patients with suspected first-time stones. 16 For young, healthy, stable patients with a history of kidney stones in whom the diagnosis is clinically clear, imag ing may be deferred until the follow-up visit, provided that a reliable follow-up mechanism exists.17 However, clinicians are frequently incorrect in their clinical impression in 20% to 70% of cases. 18 CT scanning reveals an alternative diagnosis in 33% of the patients.18 Thus, determine the need for confirmation of the diagnosis based on the patient’s past medical history, dangers of accumulated radiation exposure, clarity of the clinical diagnosis, and ease of follow-up and ability to return for worsening symptoms. CT The noncontrast CT scan is sensitive and specific, with “diagnostic” positive and negative likelihood ratios for detection of renal stones (Table 94-4).19 Images are obtained from the top of the kidney to the bladder base. Secondary signs of ureteral obstruction, such as ureteral dilatation, stranding of perinephric fat, dilatation of the collecting system, and renal enlargement, can be helpful in making the diagnosis. In combination, unilateral ureteral dilatation and perinephric stranding have a positive predictive value of 96% for stone disease.

igns of ureteral obstruction, such as ureteral dilatation, stranding of perinephric fat, dilatation of the collecting system, and renal enlargement, can be helpful in making the diagnosis. In combination, unilateral ureteral dilatation and perinephric stranding have a positive predictive value of 96% for stone disease. 20 If both are absent, the negative predictive value is 93% to 97%19 (Figures 94-1 and 94-2). Noncontrast CT has advantages over other imaging modalities, including superior speed, the avoidance of radiocontrast media, and greater ability to identify other pathologies. However, because radiocontrast is not used, the specificity and sensitivity for other diagnoses (e.g., abdominal aortic aneurysm, appendicitis, renal infarct, or perinephric abscess) are not as great as with imaging protocols using contrast, and renal function is not assessed. Tintinalli_Sec10_p0563-0606.indd 600 8/2/19 6:55 PM

because radiocontrast is not used, the specificity and sensitivity for other diagnoses (e.g., abdominal aortic aneurysm, appendicitis, renal infarct, or perinephric abscess) are not as great as with imaging protocols using contrast, and renal function is not assessed. Tintinalli_Sec10_p0563-0606.indd 600 8/2/19 6:55 PM CHAPTER 94: Urologic Stone Disease 601 FIGURE 94-2. CT image shows 5-mm stone (arrow) at left ureterovesical junction. Other calcifications are seen in the pelvis, unrelated to the urinary outflow system. Low-dose CT has been studied in small numbers. Low-dose CT is as sensitive as standard CT in detecting stones >3 mm in patients with a body mass index <30 kg/m2. However, it was not as sensitive for smaller stones or at higher body mass indices.21 IV Urography This imaging modality is not a useful imaging modality except in unusual circumstances.22 Nearly half of patients who received this test to evaluate urologic stones required a second study (usually noncontrast CT) for management.22 Plain Abdominal Radiographs Approximately 90% of urinary calculi are radiopaque because calcium phosphate and calcium oxalate stones have a density similar to that of bone. Struvite stones are typically mixed with calcium and thus are radiopaque. A plain kidney-ureter-bladder film is neither sensitive nor specific enough to rule in or rule out a stone. However, once the location of a stone is identified on CT scan, the progression of a radiopaque stone can be followed by a plain abdominal film. US US should be the first-line imaging modality in pregnant patients. Although useful in the detection of larger stones ( Figure 94-3), US may miss smaller (<5 mm in diameter) ureteral stones. 23 US is helpful in diagnosing stones in the proximal and distal ureters but is insensi tive for mid-ureteral stones. Overall, US has only modest sensitivity and specificity for detecting renal stones (Table 94-4). Reported overall FIGURE 94-3. US of renal pelvis showing stones (marked with 1+ and 2+) with shad owing effects (arrows). sensitivity of US color Doppler twinkling artifact is about 55%, with a false-positive rate of about 50% compared to CT. 24 It is not unreason able to consider US as a first-choice modality in a patient with a strong suspicion of stones, but CT should follow US if US is inconclusive. Rapid bolus infusion of crystalloid can result in a false-positive finding of hydroureter. US provides information on hydronephrosis, renal size, and, with Doppler scanning, renal blood and urine flow. Obesity may interfere with obtaining good-quality scans, and diagnostic accuracy depends on the skill and experience of the operator. One study assessing diagnostic accuracy of bedside US by ED physicians reported overall sensitivity of visualization of hydronephrosis or stones of 82.4% (95% confidence interval, 75.6% to 85.3%), but with best sensitivity for stones ≥6 mm (sensitivity, 90%; 95% confidence interval, 82% to 98%). A comparison of ED bedside US versus radiology-performed US and CT scan reported similar diagnostic accuracy among the ED and radiology US, but the best diagnostic accuracy was found with CT. TREATMENT Treatment for symptomatic nephrolithiasis in the ED includes pain and nausea/vomiting control as needed, antibiotics for those with evidence of infection, and in selected cases, medical expulsion therapy.  PAIN AND NAUSEA Forced IV hydration results in no difference in pain control or stone passage rates when compared to minimal IV hydration. 27 Fluids should be given to correct any fluid deficit due to vomiting or limited oral intake. NSAIDs have a direct action on the ureter by inhibiting prostaglandin synthesis. 28 IV administration achieves more rapid relief than IM or PO dosing29 (e.g., ketorolac, 10 to 30 milligrams IV30).

red to minimal IV hydration. 27 Fluids should be given to correct any fluid deficit due to vomiting or limited oral intake. NSAIDs have a direct action on the ureter by inhibiting prostaglandin synthesis. 28 IV administration achieves more rapid relief than IM or PO dosing29 (e.g., ketorolac, 10 to 30 milligrams IV30). There are several U.S. Food and Drug Administration boxed warnings regarding NSAID use: Do not give NSAIDS to patients with aspirin or NSAID hypersensitiv ity; avoid in coagulopathic patients or those at risk for bleeding; and avoid in patients with renal impairment. Inform the urologist if the patient is given antiplatelet drugs (NSAIDS) or if the patient is taking antithrombotics, especially if imminent surgical therapy or lithotripsy is anticipated. 31 Opioids (e.g., hydromorphone, 0.5 to 2.0 milligrams IV) are also routinely given for pain control. Because both pain and opioids may cause vomiting, antiemetics are frequently required. Lidocaine IV can reduce smooth muscle tone and reduce transmission by afferent sensory pathways. The dose is 1.5 mg/kg IV and should be given slowly to avoid numbness or dizziness. IV lidocaine may pro vide pain relief sooner than IV morphine. It is useful alone or used along with morphine. 32,33  URINARY TRACT INFECTION Patients with a ureteral stone and fever, renal insufficiency, and/or sys temic signs of infection are treated with IV antibiotics and admitted. Consult urology to determine if surgical options are indicated. 31,34 Firstdose antibiotic options include piperacillin-tazobactam, 3.375 grams IV; cefepime, 2 grams IV; ticarcillin-clavulanic acid, 3.1 grams IV; or ciprofloxacin, 400 milligrams IV . For patients without renal compromise, consider gentamicin or tobramycin, 3.0 milligrams/kg/d divided every 8 hours, plus ampicillin, 1 to 2 grams every 4 hours. Local sensitivities should guide antibiotic choice to prevent treatment failure. Patients who have a ureteral stone with an associated urinary tract infection but no evidence of significant obstruction, fever, or systemic illness can be treated as outpatients, provided follow-up in 48 to 72 hours can be accomplished (see section “Disposition and Follow-Up” later in the chapter). The choice of antibiotic should cover gram-negative rods and be appropriate for antibiotic sensitivity at your institution. Resistance rates of >10% to 20% should preclude use of that antibiotic. Choices include ciprofloxacin, 500 milligrams PO twice a day for 10 to 14 days; levofloxacin, 500 milligrams PO once a day for 10 to 14 days; cefpodoxime, 200 milligrams PO twice a day for 10 to 14 days; or others predicted to be successful based on local sensitivities. Tintinalli_Sec10_p0563-0606.indd 601 8/2/19 6:55 PM