The evaluation of suspected renal colic: ultrasound scan versus excretory urography

Terrestrial-type nitrogen-fixing symbiosis between seagrass and a marine bacterium

Symbiotic N2-fixing microorganisms have a crucial role in the assimilation of nitrogen by eukaryotes in nitrogen-limited environments1-3. Particularly among land plants, N2-fixing symbionts occur in a variety of distantly related plant lineages and often involve an intimate association between host and symbiont2,4. Descriptions of such intimate symbioses are lacking for seagrasses, which evolved around 100 million years ago from terrestrial flowering plants that migrated back to the sea5. Here we describe an N2-fixing symbiont, 'Candidatus Celerinatantimonas neptuna', that lives inside seagrass root tissue, where it provides ammonia and amino acids to its host in exchange for sugars. As such, this symbiosis is reminiscent of terrestrial N2-fixing plant symbioses. The symbiosis between Ca. C. neptuna and its host Posidonia oceanica enables highly productive seagrass meadows to thrive in the nitrogen-limited Mediterranean Sea. Relatives of Ca. C. neptuna occur worldwide in coastal ecosystems, in which they may form similar symbioses with other seagrasses and saltmarsh plants. Just like N2-fixing microorganisms might have aided the colonization of nitrogen-poor soils by early land plants6, the ancestors of Ca. C. neptuna and its relatives probably enabled flowering plants to invade nitrogen-poor marine habitats, where they formed extremely efficient blue carbon ecosystems7.

Upper Tract Imaging in Patients with Initial or Terminal Hematuria Suggestive of Bleeding from the Lower Urinary Tract: How Often is the Upper Urinary Tract Responsible for the Hematuria?

Objectives

Visible hematuria (VH) is a common urological complaint. A history of initial or terminal VH in men is indicative of a lower urinary tract (LUT) source. A careful clinical history could limit unnecessary extensive upper tract imaging in this group of patients with VH. We conducted a single-center prospective study to examine the usefulness of investigating the upper tract in patients with a history of VH likely from a LUT source (initial and/or terminal VH) with specific reference to the incidence of demonstrable significant upper tract abnormalities.

Methods

We conducted a single-center prospective study of consecutive male patients presenting with VH over eight months. All patients underwent standard investigations including physical examination, flexible cystoscopy (FC), and radiological imaging (ultrasound scan (USS) and/or computed tomography urogram (CTU)). Those with a clear history of initial or terminal VH were identified for further scrutiny with regards to detectable upper tracts abnormalities.

Results

In total, 57 patients (aged 23-95 years) with initial or terminal VH were identified. Of these, 56 had FC and nine patients were subsequently diagnosed with a LUT malignancy. With regards to upper urinary tract (UUT), 35 patients (61.4%) had an USS, 46 (80.7%) underwent a CTU, and 25 (43.9%) patients had both. In this group, no UUT malignancy was identified on upper tract imaging.

Conclusions

Initial or terminal VH patients may not need extensive upper tract imaging. FC is recommended, but a non-invasive USS can be a safe initial investigation for the UUT, with a CTU subsequently considered in those with abnormalities on USS and those with ongoing bleeding. Further combined multicenter analysis will help corroborate these findings and could have several beneficial outcomes including a reduction in investigations cost, patient inconvenience, and ionizing radiation.

[Painless hematuria: diagnostic workup using multislice computertomography]

BACKGROUND

Multislice computed tomography (MSCT) is the current standard in the work-up of hematuria. The examination protocol should be as accurate as possible while avoiding unnecessary exposure to ionizing radiation.

OBJECTIVE

To present opportunities to reduce the overall radiation dose by tailoring examination protocols to the clinical requirements.

METHODS

A four-phase MSCT protocol is an accurate tool to diagnose the cause of unclear hematuria in the majority of cases. In patients younger than 30 years and in patients younger than 40 years presenting only with microhematuria, the use a noncontrast low-dose scan is adequate. In addition, patients younger than 50 years may not require precontrast and a late-phase CT scans. Another opportunity to omit acquisitions is a combination of different phases by using the so-called split bolus injection protocol, where the administration of contrast is performed 10 min before the scan and the portal-venous phase and the late phase are combined. If dual energy is available, the precontrast scan can be calculated from the enhanced series. For the evaluation of a renal cyst, a two-phase CT protocol is sufficient to obtain diagnostic information.

Does the use of bedside ultrasonography reduce emergency department length of stay for patients with renal colic?: a pilot study

Objective

The aim of this study was to evaluate the effect of adding bedside ultrasonography to the diagnostic algorithm for nephrolithiasis on emergency department (ED) length of stay.

Methods

A prospective, randomized, controlled pilot study was conducted from October 2014 to December 2014 with patients with acute flank pain. In the non-ultrasonography group (NUSG), non-contrast computed tomography was selected based on clinical features and hematuria in the urinalysis. In the ultrasonography group (USG), non-contrast computed tomography was selected based on clinical features and hydronephrosis on bedside ultrasonography. The primary outcome was ED length of stay. The secondary outcomes were radiation exposure, amount of analgesics, proportion of patients with diseases other than ureteral calculus, and proportion of patients with unexpected ED revisits within 7 days from the index visit.

Results

A total of 103 patients were enrolled (NUSG, 51; USG, 52). The ED length of stay for the USG (89.0 minutes) was significantly shorter than that for the NUSG (163.0 minutes, P<0.001). There were no significant differences between the two groups in the radiation exposure dose (5.29 and 5.08 mSv, respectively; P=0.392), amount of analgesics (P=0.341), proportion of patients with diseases other than ureteral calculus (13.0% and 6.8%, respectively; P=0.486), and proportion of patients with unexpected ED revisits within 7 days from the index visit (7.8% and 9.6%, respectively; P=1.000).

Conclusion

The use of early bedside ultrasonography for patients with acute flank pain could reduce the ED length of stay without increasing unexpected ED revisits.

Ovarian Dermoid Cyst Causing Distal Ureteral Obstruction

A case of a 45-year old woman with an ovarian dermoid cyst causing ureteric colic secondary to distal ureteral obstruction is reported. The dermoid cyst was observed on computed tomography to be adjacent to and compressing the distal left ureter and this was confirmed at surgical exploration. Following oophorectomy, the patient's symptoms completely resolved and the excised ovarian cyst was confirmed on pathological evaluation to be a dermoid cyst. This appears to be the first reported case of ureteral obstruction caused by an ovarian dermoid cyst in the English medical literature.

The comparison of ultrasound and non-contrast helical computerized tomography for children nephrolithiasis detection

AIMS

Nephrolithiasis is less common in children than adults, but its diagnosis and management in children may be more perplexing. In this article, we compare two imaging ultrasound (US) and non-contrast helical computerized tomography (CT) for diagnosis of nephrolithiasis.

SUBJECTS AND METHODS

A total of 20 children who diagnosed as nephrolithiasis by US were imaged simultaneously by non-contrast helical CT. Their history like as family history in first and second degree relatives and urine analysis for hematuria and urine randomly calcium to creatinine ratio was obtained. All data analyzed by χ(2) and Mann-Whitney U-test in SPSS 16 and P < 0.05 was considered to be significant.

RESULTS

Out of 20 cases, only 5 cases diagnosed as nephrlithiasis by US were confirmed by CT method 2 out of 20 cases had another extrarenal origin for their complaint who diagnosed wrongly as nephrolithiasis by US. Stone size based of US that was confirmed by CT method was larger 4.6 ± 1.5 (minimum 3 max 6 mm) than non-confirmed ones 2.3 ± 0.7 mm (P 0.002). Hematuria occurred more in correct diagnosed compared with misdiagnosed (P 0.005). Positive family history and urine calcium ratio was not differed between two groups.

CONCLUSIONS

Non contrast helical CT is essential to confirm of nephrolithiasis and other extrarenal origin of complaints, which diagnosed wrongly as nephrolithiasis in children. Stone size and presence of hematuria are two major factors for right diagnosis of nephrolithiasis as US method but Urine calcium excretion ratio or positive family history cannot be predictive as this study.

Imaging evaluation in the patient with renal stone disease

Numerous imaging modalities are available for the evaluation of patients with renal stone disease. The study of choice is dependent on the clinical scenario and the indication for imaging. Additional factors such as patient age and pregnancy status will influence the radiographic study that is chosen. Currently available technologies for the evaluation of urolithiasis include plain abdominal radiography, ultrasound, intravenous pyelogram, computed tomography, and magnetic resonance imaging. This article reviews the indications, advantages, and disadvantages of each study in the evaluation of patients with known or suspected stone disease.

Urolithiasis in the emergency department

Urolithiasis commonly presents to the emergency department with acute, severe, unilateral flank pain. Patients with a suspected first-time stone or atypical presentation should be evaluated with a noncontrast computed tomography scan to confirm the diagnosis and rule out alternative diagnoses. Narcotics remain the mainstay of pain management but in select patients, nonsteroidal anti-inflammatories alone or in combination with narcotics provide safe and effective analgesia in the emergency department. Whereas most kidney stones can be managed with pain control and expectant management, obstructing kidney stones with a suspected proximal urinary tract infection are urological emergencies requiring emergent decompression, antibiotics, and resuscitation.

The learning curve of resident physicians using emergency ultrasonography for obstructive uropathy

BACKGROUND

Given the time, expense, and radiation exposure associated with computed tomography (CT), ultrasonography (US) is considered an alternative imaging study that could expedite patient care in patients with suspected obstructive uropathy. However, there is a paucity of literature regarding bedside US for obstructive uropathy in the emergency department (ED), and it is unknown how much experience is required for competency in such exams.

OBJECTIVES

The objective was to assess the learning curve for the detection of obstructive uropathy of resident physicians training in ED bedside US (EUS) during a dedicated EUS elective.

METHODS

This was a prospective cohort study of residents participating in an EUS elective. Patients presenting with acute abdominal or flank pain suggestive of an obstructive uropathy were enrolled and underwent EUS prior to noncontrast CT. Physicians who had previously performed at least 10 EUS exams for obstructive uropathy recorded results on a standardized data sheet, which was subsequently compared to the results of noncontrast CT read by board-certified radiologists blinded to the results of the EUS. In addition to an unadjusted chi-square test for trend, a multivariable logistic regression analysis, adjusting for stone size and operator, was performed. Finally, generalized estimating equations were used to describe test characteristics while accounting for potential clustering between exams by operator.

RESULTS

Twenty-three resident physicians participated and enrolled a convenience sample of 393 patients. A total of 157 patients (40%) were diagnosed with an obstructing ureterolith, and three (1%) were diagnosed with nonobstructing ureterolithiasis. An unadjusted chi-square test for trend demonstrated a statistically significant increase in both sensitivity (χ(2) = 11.4, p = 0.02) and specificity (χ(2) = 6.4, p = 0.04) for each level of increase in number of exams. On multivariable regression analysis, when adjusting for size of stone and operator, for every five additional exams after the first 10 EUS exams, the odds ratio for a true positive for obstruction increased by 1.7 (95% confidence interval [CI] = 1.2 to 2.5, p = 0.003). After accounting for clustering of exams by operator, overall EUS sensitivity and specificity for obstructive uropathy were 82% (95% CI = 77% to 87%) and 88% (95% CI = 85% to 92%). Stratifying by number of exams, the sensitivity was 72% (95% CI = 62% to 80%) for the 11th through 20th exams, 90% (95% CI = 83% to 96%) for the 21st through 30th exams, and 95% (95% CI = 91% to 99%) for the 31st through 43rd exams. Likewise, specificity was 82% (95% CI = 75% to 89%) for the 11th through 20th exams, 90% (95% CI = 85% to 95%) for the 21st through 30th exams, and 92% (95% CI = 86% to 98%) for the 31st through 50th exams.

CONCLUSIONS

Physicians training in EUS may be able to accurately assess for obstructive uropathy after 30 exams.

Can the degree of hydronephrosis on ultrasound predict kidney stone size?

OBJECTIVE

The aim of the study was to determine if the degree of hydronephrosis on focused emergency renal ultrasound correlates with kidney stone size on computed tomography.

METHODS

A retrospective study was performed on all adult patients in the emergency department who had a focused emergency renal ultrasound and ureterolithiasis on noncontrast computed tomography. Severity of hydronephrosis was determined by the performing physician. Ureteral stone size was grouped into 5 mm or less and larger than 5 mm based on likelihood of spontaneous passage.

RESULTS

One hundred seventy-seven ultrasound scans were performed on patients with ureteral calculi. When dichotomized using test characteristic analysis, patients with none or mild hydronephrosis (72.9%) were less likely to have ureteral calculi larger than 5 mm than those with moderate or severe hydronephrosis (12.4% vs 35.4%; P < .001) with a negative predictive value of 0.876 (95% confidence interval, 0.803-0.925).

CONCLUSION

Patients with less severe hydronephrosis were less likely to have larger ureteral calculi.

Diagnosis of asymptomatic primary hyperparathyroidism: proceedings of the third international workshop

OBJECTIVE

Asymptomatic primary hyperparathyroidism (PHPT) is a common clinical problem. The purpose of this report is to guide the use of diagnostic tests for this condition in clinical practice.

PARTICIPANTS

Interested professional societies selected a representative for the consensus committee and provided funding for a one-day meeting. A subgroup of this committee set the program and developed key questions for review. Consensus was established at a closed meeting that followed. The conclusions were then circulated to the participating professional societies.

EVIDENCE

Each question was addressed by a relevant literature search (on PubMed), and the data were presented for discussion at the group meeting.

CONSENSUS PROCESS

Consensus was achieved by a group meeting. Statements were prepared by all authors, with comments relating to accuracy from the diagnosis subgroup and by representatives from the participating professional societies.

CONCLUSIONS

We conclude that: 1) reference ranges should be established for serum PTH in vitamin D-replete healthy individuals; 2) second- and third-generation PTH assays are both helpful in the diagnosis of PHPT; 3) DNA sequence testing can be useful in familial hyperparathyroidism or hypercalcemia; 4) normocalcemic PHPT is a variant of the more common presentation of PHPT with hypercalcemia; 5) serum 25-hydroxyvitamin D levels should be measured and, if vitamin D insufficiency is present, it should be treated as part of any management course; and 6) the estimated glomerular filtration rate should be used to determine the level of kidney function in PHPT: an estimated glomerular filtration rate of less than 60 ml/min.1.73 m2 should be a benchmark for decisions about surgery in established asymptomatic PHPT.

Validation of emergency physician ultrasound in diagnosing hydronephrosis in ureteric colic

OBJECTIVE

Patients presenting to the ED with obstructive nephropathies benefit from early detection of hydronephrosis. Out of hours radiological imaging is expensive and disruptive to arrange. Emergency physician ultrasound (EPU) could allow rapid diagnosis and disposition. If accurate it might avert the need for formal radiological imaging, exclude an obstruction and improve patient flow through the ED.

METHODS

This was a prospective study of a convenience sample of all adult non-pregnant patients with presumed ureteric colic attending the ED with prior ethics committee approval. An emergency physician or registrar performed a focused ultrasound scan and were blinded to the patient's other management. A computerized tomography scan was also performed for all patients while in the ED or within 24 h of the EPU. The accuracy of EPU detection of hydronephrosis was determined; using computerized tomography scans reported by a senior radiologist as the 'gold-standard'.

RESULTS

Sixty-three patients with suspected ureteric colic were enrolled of whom 57 completed both EPU and computerized tomography imaging. Forty-nine had confirmed nephrolithiasis by computerized tomography with 39 having evidence of hydronephrosis. Overall prevalence of hydronephrosis was 68% (95% confidence interval [CI] 56-79%); compared with computerized tomography, EPU had a sensitivity of 80% (95% CI 65-89%); specificity of 83% (95% CI 61-94%); positive predictive value of 91% (95% CI 75-98%) and negative predictive value of 65% (95% CI 43-83%). The overall accuracy was 81% (95% CI 69-89%).

CONCLUSION

Although the accuracy of detection of hydronephrosis after focused training in EPU is encouraging, further experience and training might improve the accuracy of EPU and allow its use as a screening tool.

Prospective validation of a current algorithm including bedside US performed by emergency physicians for patients with acute flank pain suspected for renal colic

OBJECTIVE

The purpose of this study was to validate an algorithm recommended by current literature for the patients with acute flank pain and evaluate the validity of bedside ultrasonography (US) performed by emergency physicians (EP) as a part of this algorithm.

MATERIALS AND METHODS

This prospective validation study was carried out over a 5 month period in a tertiary care hospital adult emergency department (ED) with annual attendance of 55,000. Adult patients presenting to the ED with unilateral acute flank pain during the study period were enrolled into the study consecutively. Oral consent was obtained after the protocol was briefly explained to the patient and before the administration of analgesia. A protocol form was recorded for each patient enrolled into the study, and patients were followed up under the guidance of a previously designated algorithm in the ED. Data were analysed with SPSS software. The chi2 test was used to compare the dichotomised data of patients, diagnosed with and without stones, and to select the significant parameters to be used in the logistic regression.

RESULTS

Of the 227 patients enrolled, 176 were proven to have urinary tract stones. There were 122 patients discharged from ED without further investigation except urinalysis and bedside US. Of these 122 directly discharged patients, 99 had a urinary stone, and the others did not have a life threatening disorder. Four of the 227 patients were admitted to the hospital. The remaining 51 patients did not have stones detected, and their pain subsided. Having a previous history of stones, radiation of pain to the groin, accompanying nausea, and detection of pelvicalyceal dilatation using bedside US performed by the EPs were found to be the most significant parameters in determining urinary stones in logistic regression analysis. Sensitivity and specificity of these parameters were: previous history of stones 59% and 66%, radiating pain to the groin 68% and 49%, nausea 71% and 51%, and detection of pelvicalyceal dilatation by bedside US 81% and 37%.

CONCLUSION

Bedside US performed by EPs could be used safely in the evaluation of patients with acute flank pain as a part of a clinical algorithm. Previous history of urinary stones, radiation of pain to the groin, accompanying nausea. and detection of pelvicalyceal dilatation are major parameters and symptoms of urinary stone disease, and could be used in the algorithms.

[Imaging techniques and their impact in treatment management of patients with acute flank pain]

The purpose of this overview is to provide a general summary of the imaging techniques applied at the Vienna Hospital for the investigation of acute flank pain and the diagnosis of stone disease and the evaluation of their efficacy and impact on therapy management. The number of publications on the issue of "intravenous urography (IVU) vs computed tomography (CT)" is abundant; in recent years, advocates of CT make up the majority. In the Department of Urology at the Vienna Hospital, conventional techniques such as ultrasound and IVU besides UHCT still play an important role. This overview presents the advantages and disadvantages of the various imaging techniques for diagnosis of stone disease and evaluates their significance regarding therapy management of patients with acute flank pain.

Sonographic mimics of renal calculi

OBJECTIVES

To review sonographic findings that can mimic renal calculi.

METHODS

We comment on a number of echoes that can mimic renal calculi.

RESULTS

There are a number of sonographic renal artifacts, vascular and nonvascular, that may confound a correct diagnosis.

CONCLUSIONS

Awareness of these potential artifacts will result in a more specific sonographic examination and will accurately guide the referring physician toward appropriate patient treatment. The importance of other imaging modalities is also emphasized to ensure that a correct diagnosis is obtained whenever the sonographic findings are inconclusive.

Renal ultrasound

Renal US is one of several imaging modalities available to the EP in the evaluation of patients with acute urologic disorders. It offers excellent anatomic detail without exposure to radiation or contrast agents but is limited in its assessment of renal function. It is an important alternative to helical CT scanning for evaluating renal colic, especially in children and pregnant women. It has an important role in excluding bilateral renal obstruction as the cause of acute renal failure. It is likely that Doppler renal US also will take on a prominent role in the evaluation of renal vascular disorders. It already has become the standard of care in the management of renal transplant patients. Bedside emergency renal US performed and interpreted by EPs with limited training and experience is increasing in use and gaining acceptance. At present, the primary role of renal US is to identify hydronephrosis in patients with renal colic or acute renal failure but, in the future, its role likely will expand as technology advances and its use increases. In many patients, bedside renal US may obviate the need for further diagnostic workup and speed the diagnosis and treatment of an emergency patient.

Urinary tract stones--Part I: role of radiological imaging in diagnosis and treatment planning

The modern management of urolithiasis requires a multi-disciplinary approach. Imaging plays a central role in both diagnosis and planning therapy of renal and ureteric calculi. This article reviews the current status of diagnosis and management of stone disease, and the contribution of radiological imaging in accurately triaging a given case to the most appropriate therapy.

Imaging for microscopic haematuria

For evaluation of the upper urinary tract, intravenous urography has for many years been the method of choice. In recent years, different imaging protocols have been suggested. In this article different strategies for the evaluation of microscopic haematuria, with a focus on the advantages and disadvantages of different imaging modalities, will be discussed.

Nephrolithiasis

This article covers the diagnosis and management of renal colic. New imaging modalities will be reviewed using evidence-based medicine. The disposition of the patient with renal colic will be addressed. Additionally, special groups with nephrolithiasis will be discussed.

A new diagnostic algorithm for the evaluation of microscopic hematuria

OBJECTIVES

To evaluate a new diagnostic algorithm for microscopic hematuria in which intravenous urography (IVU) is performed as a secondary radiographic study when microhematuria has persisted for 3 months after the initial workup with renal ultrasound (US) and cystoscopy was negative.

METHODS

We evaluated 372 consecutive patients who presented with microhematuria and negative urine cultures and cytologic findings at our institution. All patients underwent renal US scanning and cystoscopy as their initial evaluation. All patients underwent re-evaluation 3 months after the initial workup. Patients with persistent microhematuria with no apparent etiology were then evaluated with IVU.

RESULTS

The initial evaluation was negative in 212 of 372 patients. Eighty-one of these patients had persistence of their microhematuria at the 3-month follow-up without a definitive diagnosis. Seventy-five of these patients underwent IVU. Abnormalities were found in 11 of the 75 patients. Six patients had renal stones, two had ureteral stones, two had ureteral tumors, and one had a tumor of the renal pelvis. Forty of the 131 patients with resolution of their microhematuria underwent IVU at their request. All those studies were normal.

CONCLUSIONS

The combination of cystoscopy and renal US along with urinalysis, urine culture, and cytology is a good initial evaluation in patients with microhematuria. Those patients with persistent microhematuria after 3 months without definite etiology of the bleeding may still benefit from IVU.

Nonenhanced helical CT and US in the emergency evaluation of patients with renal colic: prospective comparison

PURPOSE

To compare nonenhanced helical computed tomography (CT) with ultrasonography (US) for the depiction of urolithiasis.

MATERIALS AND METHODS

During 9 months, 45 patients (mean age, 44 years; mean weight, 92.5 kg) prospectively underwent both nonenhanced helical CT (5-mm collimation; pitch of 1.5) and US of the kidneys, ureters, and bladder. US evaluation included a careful search for ureteral calculi. Presence of calculi and obstruction and incidental diagnoses were recorded. Clinical, surgical, and/or imaging follow-up data were obtained in all patients. The McNemar test was used to compare groups.

RESULTS

Diagnoses included 23 ureteral calculi and one each of renal cell carcinoma, appendicitis, ureteropelvic junction obstruction, renal subcapsular hematoma, cholelithiasis, medullary calcinosis, and myelolipoma. CT depicted 22 of 23 ureteral calculi (sensitivity, 96%). US depicted 14 of 23 ureteral calculi (sensitivity, 61%). Differences in sensitivity were statistically significant (P: =.02). Specificity for each technique was 100%. When modalities were compared for the detection of any clinically relevant abnormality (eg, unilateral hydronephrosis and/or urolithiasis in patients with an obstructing calculus), sensitivities of US and CT increased to 92% and 100%, respectively. One case of appendicitis was missed at US, whereas medullary calcinosis and myelolipoma were missed at CT.

CONCLUSION

Nonenhanced CT has a higher sensitivity for the detection of ureteral calculi compared with US.

Nongynecologic applications of transvaginal US

Transvaginal ultrasonography (US) is a noninvasive, readily available imaging technique that has greatly enhanced diagnostic sensitivity and accuracy for both gynecologic and nongynecologic disease. High-frequency US probes placed in the vagina allow high-resolution assessment of all the pelvic viscera, including portions of the gut and urinary tract. In addition, they allow visualization of the peritoneum of the pelvic pouch and the pelvic side walls without interference from bowel gas or adipose tissue. Evaluation of these areas requires a modified US technique that includes the use of the highest-frequency probes with angulation of the transducer to allow assessment of the region of interest. In women of childbearing age, the similarity of symptoms in gynecologic and gastrointestinal tract disease in particular underscores the potential utility of transvaginal US, which may, for example, help differentiate appendicitis in a pelvic appendix from pelvic inflammatory disease. Transvaginal US may also help determine the correct course of therapy, thereby improving patient management. Other indications for transvaginal US include assessment for pelvic appendicitis and diverticulitis, rectal and perianal complications of Crohn disease, and ureteric and bladder calculi and tumors as well as evaluation of the anal sphincters in women with fecal incontinence. Transvaginal US is also superior to routine US in the detection and characterization of ascites and peritoneal disease. Transvaginal US examination should include the entire pelvic cavity and contents, especially in women at risk for pelvic sepsis or peritoneal disease.

Prospective comparison of unenhanced spiral computed tomography and intravenous urogram in the evaluation of acute flank pain

OBJECTIVES

To prospectively compare the diagnostic ability of unenhanced spiral computed tomography (NCCT) and intravenous urogram (IVU) in the evaluation of adults with acute flank pain.

METHODS

After giving informed consent, 106 adult patients with acute flank pain suspected of having urolithiasis underwent NCCT followed by IVU. Subsequent follow-up was scheduled within 72 hours in the Urology Clinic. Each NCCT was read by a single radiologist who was unaware of clinical history and IVU results. Each IVU was read by a different radiologist who was unaware of clinical history and NCCT results. Sensitivity, specificity, and positive and negative predictive values were determined for NCCT and IVU.

RESULTS

The diagnosis of ureterolithiasis was defined as unequivocal evidence of urolithiasis on either NCCT or IVP. Seventy-five of 106 patients evaluated were diagnosed with ureterolithiasis. Clinical follow-up was available in 74 (98%) stone patients and in 31 (100%) of 31 non-stone patients. In 72 of the 75 patients diagnosed with ureteral calculi, the NCCT made the diagnosis. IVU made the diagnosis in 65 of the 75 patients. Of the 31 patients without ureterolithiasis, the NCCT was negative in all cases. IVU was negative in 29 of the 31 cases. Unenhanced spiral CT was 96% sensitive and 100% specific (P <0.001). IVU was 87% sensitive and 94% specific (P <0.001). Compared with IVU, using the log odds ratio and Fisher's exact test, NCCT was significantly better able to predict the presence of urolithiasis (P=0.015).

CONCLUSIONS

NCCT accurately diagnoses ureterolithiasis in patients presenting with acute flank pain. NCCT is significantly better than IVU in determining the presence of urolithiasis.

Ruptured renal angiomyolipoma presenting as renal colic

The case of a patient with acute onset of flank pain and hematuria is presented. Initial therapy was directed toward relief of pain believed to be caused by renal colic. It was not until the patient developed atypical features that the true diagnosis, ruptured renal angiomyolipoma, was discovered. The case and discussion emphasize the need to carefully consider a complete differential diagnosis when evaluating patients with flank pain and hematuria who have atypical clinical features or an atypical course.

Ultrasonography by emergency physicians in patients with suspected ureteral colic

We performed a prospective study of patients with suspected ureteral colic to evaluate the test characteristics of bedside renal ultrasonography (US) performed by emergency physicians (EPs) for detecting hydronephrosis, and to evaluate how US can be used to predict the likelihood of nephrolithiasis. Thirteen EPs performed US, recorded the presence of hydronephrosis, and made an assessment of the likelihood of nephrolithiasis. All patients underwent i.v. pyelography (IVP) or unenhanced helical computed tomography (CT). There were 126 patients in the study: 84 underwent IVP; 42 underwent helical CT. Test characteristics of bedside US for detecting hydronephrosis were: sensitivity 72%, specificity 73%, positive predictive value (PPV) 85%, negative predictive value (NPV) 54%, accuracy 72%. The PPV and NPV for the ability of the EP to predict nephrolithiasis after performing US were 86% and 75%, respectively. We conclude that bedside US performed by EPs may be used to detect hydronephrosis and help predict the presence of nephrolithiasis.

Bedside emergency department ultrasonography plus radiography of the kidneys, ureters, and bladder vs intravenous pyelography in the evaluation of suspected ureteral colic

OBJECTIVE

To determine the role of bedside renal ultrasonography (US) and plain radiography of the kidneys, ureters, and bladder (KUB) as the initial investigative modality for those patients presenting to the ED with unilateral flank pain and hematuria. The hypothesis was that the renal US + KUB may obviate the need for emergent i.v. pyelography (i.v.P) in a majority of patients.

METHODS

Prospective study over an 8-month period of all consecutive adult patients between the ages of 18 and 65 years presenting with unilateral flank pain and hematuria to the ED at LAC + USC Medical Center. Patients received KUB followed by a 500-mL bolus of normal saline. Bedside US was then performed by emergency physicians (EPs). Hydronephrosis of the kidney was graded as mild, moderate, or severe. All patients then underwent i.v.P. The results of the bedside US + KUB were then compared with those of i.v.P (the criterion standard).

RESULTS

Of a total of 139 eligible patients, 108 were enrolled. The combination of US and KUB correctly identified pathology consistent with nephroureterolithiasis with a sensitivity of 97.1% (95% CI = 93.1-100%) when compared with i.v.P. The KUB + US results were falsely positive in 16 patients, resulting in a specificity of 58.9% (95% CI = 43.5-74.3%). The positive predictive value of the combined modality was 80.7%, the negative predictive value was 92.0%, and the overall accuracy was 83.3%.

CONCLUSION

The bedside US + KUB has a high sensitivity and can be performed rapidly at the bedside by the EP when compared with i.v.P. This combined modality is an effective screening tool in the initial evaluation of ureteral colic.

Prevalence and structure of ultrasound curricula in emergency medicine residencies

Emergency medicine (EM) residency program directors were surveyed to determine the presence and structure of curricula for teaching ultrasound to EM residents. For those EM programs without an ultrasound curriculum (USC), information was requested on plans to implement one within the next 12 months. Ninety of 116 (78%) EM programs replied to the survey. One-half of EM residencies surveyed have USCs, and another 30% plan to implement one in the near future.

Renal ultrasonography

Renal US is one of several imaging modalities available to the emergency physician in the evaluation of patients with acute urologic disorders. It offers excellent anatomic detail without exposure to radiation or contrast agents but does not assess renal function. It is particularly useful in the evaluation of renal colic, although its role here may decrease with increasing availability of helical CT. It also has an important role in excluding bilateral renal obstruction as the cause of acute renal failure. Doppler renal US is likely to take on a more prominent role in the evaluation of renal trauma and is the diagnostic study of choice to rule out renal vein thrombosis. Bedside emergency renal US performed and interpreted by emergency physicians with limited training and experience is gaining in use and acceptance. Its role at present is primarily to identify unilateral hydronephrosis in patients with suspected renal colic. This role is likely to expand in the future as emergency US use grows and technology advances. Bedside emergency renal US may eventually be used in the evaluation of patients with acute renal failure, suspected renal vein thrombosis, and renal trauma.

Radiographic imaging modalities for the patient in the emergency department with abdominal complaints

The emergency physician should be aware of the sensitivity and specificity of any radiologic study being considered. Radiographic examinations should be used to answer specific questions raised by the history and physical examination. The need to obtain a given radiologic evaluation should be based on the potential information it may reveal and the likelihood that this information will alter patient care. This cost-effective approach minimizes unnecessary radiation exposure and has been advocated by many authorities. The emergency physician should resist the "knee jerk" tendency to order radiographs to reassure himself or herself of the safety of the patient at discharge. Documentational and legal concerns are equally invalid reasons, as is the feeling that "it's what we always order for patients with this abdominal complaint." A given study may be indicated if the yield is acceptable and treatment of the patient may be altered by the results.

Model curriculum for physician training in emergency ultrasonography

A model curriculum for the implementation and training of physicians in emergency medicine ultrasonography is described. Widespread use of limited bedside ultrasonography by emergency physicians will improve diagnostic accuracy and efficiency, increase the quality of care, and prove to be a cost-effective technique for the practice of emergency medicine.

Ultrasonography and plain film versus intravenous urography in ureteric colic

Urography (IVU) is considered the best first investigation in patients with suspected ureteric colic, but recently ultrasonography (US), combined with a plain film of the abdomen (KUB), has been suggested as an alternative. We have undertaken a prospective study to see if this approach can be used in an Emergency Department by radiologists with different amounts of ultrasound experience. Some 180 patients with suspected ureteric colic presenting to the Emergency Department over an 8-month period were studied. They had a plain abdominal film (KUB) and US examination of the kidneys, ureters and bladder following hydration. Some 120 patients subsequently underwent IVU at a mean interval of 3.5 days after the ultrasound examination. Of these, 15 patients passed a stone before their IVU. Of the remaining 105 patients, 44 had an IVU positive for stone and 61 had a negative IVU. Fifty of the 60 patients who did not have an IVU had clinical follow-up and 31 had ultrasound. Our findings in this prospective study suggest that in the hydrated patient the combination of KUB plus US is a sensitive but not very specific screening test (sensitivity 95%, specificity 67%). Because of the high negative predictive value of KUB plus US (95%), urography is not likely to be helpful when KUB plus US are negative. Urography is indicated only if KUB plus US findings are equivocal or if intervention is necessary. If we had used KUB plus US alone as the first test in our patients, urography would have been unnecessary in approximately 60%. Twenty per cent of our patients passed a stone in the first 48 h.

Sonographic detection of ureteral calculi in patients with normal excretory urography

We report 3 cases of nonobstructing distal ureteral calculi diagnosed by sonography in which excretory urography was normal. In each case sonography was performed because of high clinical suspicion for a ureteral stone. In 2 patients a stone was impacted at an edematous ureteral orifice. All 3 patients subsequently passed the stone spontaneously. A high resolution ultrasound examination should be performed on patients with a history suggestive of ureteral calculus despite a normal excretory urogram.

Acute renal failure due to urinary tract obstruction

Urinary tract obstruction is a frequent cause of acute renal failure that is potentially life threatening but reversible, if it is promptly recognized and corrected. The level of urinary tract obstruction is variable, dependent on the underlying disease, and may range from the loop of Henle to the urethral meatus. Clinical manifestations are most commonly due to renal failure, but the history and physical examination can aid in determining the localization and cause of the obstruction. Laboratory findings may suggest urinary tract obstruction as the etiology for acute renal failure. Radiologic procedures, most prominently ultrasonography, can establish the diagnosis. Treatment is variable, but patient management may need to be altered during the postobstructive phase of urinary tract obstruction owing to physiologic response to reestablishment of urine flow.