Torsion of testicular appendages can result in the clinical presentation of acute scrotum. Two such appendages are the appendix testis, a remnant of the paramesonephric (müllerian) duct, and the appendix epididymis, a remnant of the mesonephric (wolffian) duct. Most acute presentations of scrotal pain and swelling can be attributed to epididymitis, testicular torsion, or torsion of a testicular appendage. Presentation of these conditions typically can be distinguished by history and physical examination. However, in many cases, torsion of a testicular appendage, although a benign condition, may present identically to testicular torsion—a true urologic emergency.
The term acute scrotum encompasses a plethora of testicular pathologies that are detrimental to survival and sustenance of the testes.[1]
Acute scrotum pain is defined as “the constellation of new-onset pain, swelling, and/or tenderness of the intrascrotal contents.” Patients may describe the onset of symptoms as rapidly occurring within minutes or over up to 1-2 days, depending on the etiology. Acute scrotum is an umbrella term that includes a wide variety of unique disease processes. Rapid evaluation and diagnostics are necessary because of the time dependency of certain morbid but reversible conditions, such as acute testicular torsion.[2]
Acute testicular pain in childhood can be caused by testicular torsion, torsion of the appendix testis, or epididymo-orchitis. Quick and reliable diagnosis is essential for determining the further course of action (surgery or a conservative treatment approach).[3] Delay in diagnosis and subsequent delay in surgery, if needed, can lead to loss of testicular viability and orchidectomy.[4]
Torsion of the testicular appendices is virtually a benign condition but must be distinguished from testicular torsion, which can have permanent consequences for testicular viability.
Testicular torsion as reported in children and preadolescents is an emergency medical condition that requires prompt surgical treatment. In cases of testicular torsion, early and accurate diagnosis of acute scrotum is important for preserving testicular fertility. A retrospective study reported that patient age, white blood cell count, and laterality are key factors distinguishing testicular torsion from acute scrotum. Trial authors reported that salvageability depended to a great extent on the duration of symptoms and the degree of testicular torsion. The salvage rate of the testis can be improved by educating pediatricians, parents, patients, and medical staff about the importance of early diagnosis of torsion and prompt treatment.[5]
Diagnosis
Lab studies include urinalysis and CBC with differential.
Imaging of the scrotum in the setting of acute symptoms such as pain or swelling is commonly performed emergently to differentiate between patients who require immediate surgery and those who do not.[6]
Ultrasound is the well-established first-line imaging modality for acute scrotum. Contrast-enhanced ultrasound and magnetic resonance imaging (MRI) can be useful as problem-solving tools when ultrasound studies are inconclusive or equivocal.[6]
Treatment
Necrotic tissue of the testicular appendices causes no damage other than damage to itself. Most cases, therefore, are treated conservatively. Pain usually resolves within 1 week but may persist for several weeks. Uncontrolled pain can be relieved by surgical excision of the appendix.
NSAIDs and ice are the mainstays of therapy for inflammation, and reduced activity and scrotal support are indicated.
If the diagnosis is unclear and testicular torsion cannot be ruled out, or if pain persists, surgical exploration is warranted.[7]
The prognosis for patients with torsion of testicular appendages is excellent. Long-term sequelae do not exist. Virtually all patients have an uneventful recovery.
Testicular torsion. Epididymo-orchitis. Longitudinal color Doppler image of the left testis shows diffuse, markedly increased vascularity.
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Testicular torsion. Scrotal hernia. Transverse color Doppler image of the left hemiscrotum shows heterogeneous mass superior to the testicle, with sma....
The appendix testis is present in 92% of all testes and is usually located at the superior testicular pole in the groove between the testicle and the epididymis. The appendix epididymis is present in 23% of testes and usually projects from the head of the epididymis, but its location may vary.
The vestigial tissues forming the appendices are commonly pedunculated and are structurally predisposed to torsion. Torsion of an appendage leads to ischemia and infarction. Necrosis of appendices causes pain and local inflammation of the surrounding tunica vaginalis and epididymis (acute hemiscrotum). Torsion of the testicular appendage may be accompanied by a thickened scrotal wall, a reactive hydrocele, and enlargement of the head of the epididymis.
Acute scrotum is characterized by intense acute scrotal pain, which may be associated with other symptoms and signs, such as abdominal pain, inflammation, and fever. Many pathologic conditions can present in this way, most of which involve scrotal contents.[8]
Torsion of testicular appendices is one of the most common causes of acute scrotum; it is the leading cause of acute scrotum in children.
In several retrospective reviews of pediatric patients who presented to the emergency department (ED) with acute scrotal pain, the incidence of torsed testicular appendage ranged from 46 to 71%, and testicular torsion represented the most common cause of scrotal pain.
A study of 155 scrotal explorations performed for acute scrotal pain found that the pathology was as follows: testicular torsion in 46.5% (N = 72); torsion of a testicular appendage in 30.3% (N = 47); epididymitis in 16.1% (N = 25); no obvious pathology in 3.3% (N = 5); and other pathology in 4%. Mean participant age was 9.1 years (range, 0-15 years), and there was a significant difference in age of presentation between those with testicular torsion and those with torsion of a testicular appendage (9 vs 10 years; P=0.0074).[9]
In a retrospective study of 76 patients younger than 15 years with acute scrotal pain, 59 (78%) had acute spermatic cord torsion, 16 (21%) had torsion of the testicular appendage, and 1 (1%) had orchitis. Among patients with acute spermatic cord torsion, median age was 13 years (range, 0.18-14.97 yr).[10]
Mortality/Morbidity
Torsion of the testicular appendices is virtually a benign condition, but again, it must be distinguished from testicular torsion, which can have permanent consequences for testicular viability.
Necrotic tissue is reabsorbed without any sequelae in almost all cases.
The literature contains a single case report of a scrotal abscess secondary to tissue necrosis.
Some cases of persistent pain due to torsion of the testicular appendix have required surgical excision for relief or often for diagnostic surgical exploration.
Little evidence supports the suggestion that scrotal calculi can form due to calcification of the necrotic appendix.
A retrospective study by Rakha et al demonstrated no evidence of any bacterial or fungal infection in 79 cases of torsion of the testicular appendage. Histologic analysis showed no correlation between degree of inflammatory infiltrate and pyogenic infection.[11]
Greatest morbidity results from a missed diagnosis of testicular torsion and a subsequent delay in treatment.
Age
Patient age ranges from infancy to adulthood, with more than 80% of cases occurring in children 7-14 years of age. Mean age is 10.6 years. This condition rarely presents in adulthood (probably due to local fibrosis). Torsion of testicular appendices is the leading cause of acute scrotum in children.[9, 10, 12, 13]
Torsion of an epididymal cyst is an extremely rare cause of acute scrotum in children and in young boys, with a reported incidence of 5-20%. Treatment is usually conservative. Many cases (up to 60%) regress spontaneously, especially if measuring less than 3 cm.[14]
Testicular torsion occurs most frequently at a pre-adulthood age. In geriatric people, it is very rare, but this should not be an exclusion criterion for the diagnosis. Lack of awareness about testicular torsion in elderly people may lead to delayed or inaccurate diagnosis.[15]
Patient history is important in distinguishing torsion of the testicular appendages from testicular torsion and other causes of acute scrotum.
The most common cause of acute scrotum in prepubertal boys is torsion of the testicular or epididymal appendages.[16]
Pain may be present. Onset is usually acute, but pain may develop over time. Intensity ranges from mild to severe. Patients may endure pain for several days before seeking medical attention. The pain is located in the superior pole of the testicle. This is a key distinguishing factor from testicular torsion. A focal point of pain in the testicle is uncommon in complete testicular torsion.
Systemic symptoms are absent. Nausea and vomiting (frequently seen in testicular torsion) usually are not associated with this condition.
Urinary symptoms are absent. Dysuria and pyuria are not associated with torsion of the testicular appendages. Their presence is more indicative of epididymitis.
Physical examination may reveal the following findings[12] :
The patient is afebrile with normal vital signs.
Although the scrotum may be erythematous and edematous, it usually appears normal.
An unreliable marker of pathology, the cremasteric reflex is usually intact. Several studies have found that a cremasteric reflex in the acute scrotum is unlikely to indicate testicular torsion.
The testis should be nontender to palpation. If present, tenderness is localized to the upper pole of the testis. Diffuse tenderness is more common in testicular torsion.
A paratesticular nodule at the superior aspect of the testicle, with its characteristic blue-dot appearance, is pathognomonic for this condition. A blue-dot sign is present in only 21% of cases.
The combination of a blue-dot sign with clear palpation of underlying normal, nontender testes allows for exclusion of testicular torsion on clinical grounds alone.
Vertical orientation of the testes is preserved.
In one study, researchers identified 3 key historical elements that serve as predictors for testicular torsion: duration of pain less than 6 hours, absence of cremasteric reflex, and diffuse testicular tenderness. None of the 141 study participants had testicular torsion in the absence of any of these elements. When all 3 elements were present, testicular torsion was diagnosed in 87% of patients.[17]
Imaging of the scrotum in the setting of acute symptoms such as pain or swelling is commonly performed emergently to differentiate between patients who require immediate surgery and those who do not. Acute scrotal symptoms generally are caused by infectious, traumatic, or vascular etiologies.[6]
Ultrasonography is the well-established first-line imaging modality for acute scrotum. Contrast-enhanced ultrasound and MRI can be useful as problem-solving tools when ultrasound studies are inconclusive or equivocal.[6]
Lab studies include urinalysis and CBC with differential.
Ultrasonography
Torsion of the testicular appendages represents the most common cause of acute scrotum in prepubertal boys. Torsion of the testicular appendages has a set of features on multiparametric ultrasonography. Awareness of these features can facilitate diagnosis of torsion of the testicular appendages with no need for unnecessary surgical scrotal exploration or unwarranted antibiotic treatment.[18]
Ultrasonography can be useful in distinguishing torsion of a testicle and torsion of an appendix testis. Testicular appendage torsion appears as a lesion of low echogenicity with a central hypoechogenic area. The presence of a large appendix adjacent to the epididymis (in the absence of clinically detectable inflammation) may signify testicular involvement. If the edematous appendix and the head of the epididymis are close enough, this condition will have a "Mickey Mouse" appearance on transverse view.
In a retrospective study of 241 boys with acute scrotal pain, the best predictors for epididymitis were dysuria, a painful epididymis on palpation, and altered epididymal echogenicity and increased peritesticular perfusion on ultrasound studies; for appendix testis, the best predictor was a positive blue-dot sign.[19]
Color Doppler ultrasonography
Color Doppler ultrasonography (CDU) is the imaging modality of choice for evaluation of acute scrotum.[16, 20, 21] In torsion of the testicular appendage, CDU shows normal blood flow to the testis, with an occasional increase on the affected side that may be due to inflammation. In prepubertal patients, this method of imaging is somewhat controversial because the prepubertal testis has low-velocity blood flow, and CDU is less accurate in these instances.
Standard ultrasonography of the scrotum should include both grayscale and Doppler studies. Linear high-resolution transducers should be used, and studies should include both the scrotum and inguinal areas. In patients with torsion, a normal homogeneous echo pattern is likely to indicate a viable testis, whereas a hypoechoic or inhomogeneous testis is likely to be nonviable.[22]
Some studies suggest that CDU has 90% sensitivity and 98% specificity in diagnosing acute testicular torsion. However, variability in the sensitivity of CDU has been noted. As a result, a negative ultrasonographic result does not necessarily exclude testicular torsion.
A study by Pepe et al demonstrated that CDU specificity may not be as high for testicular torsion as was previously reported.[23] In a subset analysis of 42 adolescents with diagnostic suspicion of testicular torsion by CDU, only 22 had surgical confirmation of this diagnosis; 16 were found to be norma,l and 4 had torsion of the testicular appendage. In fact, clinical examination alone had sensitivity and specificity of 100% and 50%, respectively, and CDU had sensitivity and specificity of 95.7% and 48.7%, respectively. In a patient presenting with an acute scrotum, a negative CDU result may provide supportive evidence of a benign condition such as torsion of an appendage, but it does not exclude the diagnosis of testicular torsion. In cases of high clinical suspicion, surgical exploration may be warranted.
Radionuclide imaging
Since Doppler ultrasonography has been accepted as the primary imaging modality for evaluation of acute scrotum, radionuclide scrotal imaging (RNSI) is used uncommonly.[22] The positive sign for testicular appendix torsion is the hot-dot sign, which shows an area of increased tracer uptake. This sign is pathognomonic for testicular appendix torsion. Radionuclide images do not show a positive result if symptoms have been present for less than 5 hours. Positive results are seen in only 45% of patients whose symptoms have lasted 5-24 hours.[24] This test is reported to be 68% sensitive and 79% accurate.[24]
Magnetic Resonance Imaging
Magnetic resonance imaging (MRI) techniques typically are not used for assessment of the acute scrotum because of limited availability of equipment and the long examination time involved. However, use of MRI in scrotal disease is increasing, and future studies will help determine the role of MRI in patients who have acute scrotal pain but equivocal CDU findings.[22]
Testicular torsion is an important and critical issue in patients with acute scrotum presenting to the ED. Early detection is very important for saving the testicles. A prospective cross-sectional study concluded that clinical variables are not accurate enough to be considered as the sole predictor of testicular torsion; they should be used with caution and in combination with other available screening tools such as Doppler ultrasonography.[25]
If the diagnosis is unclear and testicular torsion cannot be ruled out, or if pain persists, surgical exploration is warranted.[7]
Necrotic tissue in the testicular appendix causes no damage other than damage to itself. Most cases, therefore, are treated conservatively. Pain usually resolves within 1 week but may persist for several weeks. Uncontrolled pain can be relieved by surgical excision of the appendix.
NSAIDs and ice are the mainstays of therapy for inflammation, and reduced activity and scrotal support are indicated.
If the diagnosis is unclear and testicular torsion cannot be ruled out or if pain persists, surgical exploration is warranted.[7]
The American College of Radiology has published the following guidelines for treating patients with acute scrotum[22] :
When the clinician has a strong clinical suspicion of testicular torsion, the patient may be referred promptly for scrotal exploration.
Color Doppler ultrasonography (CDU) with grayscale imaging and special attention to the spermatic cord is the study of choice for evaluating patients with acute scrotal pain because of its widespread availability and its ability to diagnose testicular torsion with a high degree of sensitivity and specificity and to distinguish other causes of scrotal pain and swelling.
Radionuclide scrotal imaging (RNSI) is used infrequently because of longer examination times, less availability, use of radiation, and diminished diagnostic capability in young boys.
If CDU is performed and results are equivocal for testicular torsion, scrotal exploration may be undertaken.
Studies are needed to explore the role of MRI in patients who have acute scrotal pain but equivocal CDU findings.
Clinical Context:
Drug of choice (DOC) for patients with mild to moderate pain. Inhibits inflammatory reactions and pain by decreasing prostaglandin synthesis.
These agents have anti-inflammatory and antipyretic activities. Their mechanism of action is not known, but they may inhibit cyclooxygenase activity and prostaglandin synthesis. Other mechanisms may exist as well, such as inhibition of leukotriene synthesis, lysosomal enzyme release, lipoxygenase activity, neutrophil aggregation, and various cell membrane functions.
Jason S Chang, MD, Clinical Instructor, Department of Emergency Medicine, University of Pittsburgh Medical Center
Disclosure: Nothing to disclose.
Specialty Editors
Francisco Talavera, PharmD, PhD, Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference
Disclosure: Received salary from Medscape for employment. for: Medscape.
Richard H Sinert, DO, Professor of Emergency Medicine, Clinical Assistant Professor of Medicine, Research Director, State University of New York College of Medicine; Consulting Staff, Vice-Chair in Charge of Research, Department of Emergency Medicine, Kings County Hospital Center
Disclosure: Nothing to disclose.
Chief Editor
Erik D Schraga, MD, Staff Physician, Department of Emergency Medicine, Mills-Peninsula Emergency Medical Associates
Disclosure: Nothing to disclose.
Additional Contributors
Theodore J Gaeta, DO, MPH, FACEP, Clinical Associate Professor, Department of Emergency Medicine, Weill Cornell Medical College; Vice Chairman and Program Director of Emergency Medicine Residency Program, Department of Emergency Medicine, New York Methodist Hospital; Academic Chair, Adjunct Professor, Department of Emergency Medicine, St George's University School of Medicine
Disclosure: Nothing to disclose.
Acknowledgements
The authors and editors of Medscape Reference gratefully acknowledge the contributions of previous authors, Sean O Henderson, MD, and Gregory Alfred, MD, to the development and writing of this article.
Testicular torsion. Epididymo-orchitis. Longitudinal color Doppler image of the left testis shows diffuse, markedly increased vascularity.
Testicular torsion. Scrotal hernia. Transverse color Doppler image of the left hemiscrotum shows heterogeneous mass superior to the testicle, with small vessels depicted.
Testicular torsion. Epididymo-orchitis. Longitudinal color Doppler image of the left testis shows diffuse, markedly increased vascularity.
Testicular torsion. Scrotal hernia. Transverse color Doppler image of the left hemiscrotum shows heterogeneous mass superior to the testicle, with small vessels depicted.
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