Visceral injury without hemoperitoneum: A limitation of screening abdominal sonography for trauma

Abdominal sonography for the detection of hemoperitoneum has become increasingly popular as a screening test for visceral injury after blunt trauma. The purpose of this study was to determine the frequency, severity, and clinical significance (outcome) of abdominal organ injuries that occur without hemoperitoneum on the initial evaluation of blunt abdominal trauma patients.During a 12-month period, 3392 blunt trauma patients were admitted to our center. Sonographic studies were performed as an initial screening evaluation to determine the presence of hemoperitoneum in 772 (22.7%) of these patients. Abdominal visceral injuries were verified by computed tomography (CT) or surgery in 196 (5.8%) of all blunt trauma admissions. Sonography, CT, and operative findings were reviewed to determine the presence or absence of hemoperitoneum in patients with abdominal injury. Patients with abdominal visceral injury without hemoperitoneum were further analyzed to identify the type of injury and the management required.A total of 246 abdominal injuries were identified in 196 patients. Fifty (26%) patients with abdominal visceral injuries diagnosed by admission CT scan had no evidence of hemoperitoneum. Admission sonography performed in 15 (30%) of these 50 patients also showed no evidence of hemoperitoneum. Visceral injuries detected by CT in the patients without hemoperitoneum included 22 of 100 splenic injuries (22%), 18 of 91 hepatic injuries (20%), 12 of 26 renal injuries (46%), and 1 of 9 mesenteric injuries (11%). Surgery was required to manage injuries in 10 of these patients.Up to 26% of blunt trauma patients with abdominal visceral injuries do not have associated hemoperitoneum identified on admission abdominal CT or sonography. Dependence on hemoperitoneum as the sole criterion of abdominal visceral injury after blunt trauma will result in falsely negative examinations and will miss potentially significant injuries.     

Hemoperitoneum as the sole indicator of abdominal visceral injuries: a potential limitation of screening abdominal US for trauma.

PURPOSE: To determine, at screening ultrasonography, the prevalence, severity, and clinical outcome of clinically important abdominal visceral injuries, without associated hemoperitoneum, that result from blunt abdominal trauma. MATERIALS AND METHODS: Computed tomography (CT) was performed at admission in 466 patients with visceral injury. A retrospective review was performed of findings from surgery and contrast material-enhanced spiral and conventional CT performed to verify abdominal visceral injuries in 467 (4%) of 11,188 patients with blunt trauma. These patients were admitted to a level 1 trauma center over 33 months to determine the presence of hemoperitoneum and to identify the grade of injury. Medical records of patients with abdominal visceral injury without hemoperitoneum were reviewed for the management required and for results of focused abdominal sonography for trauma (FAST). RESULTS: A total of 575 abdominal visceral injuries were identified at CT and/or surgery. Findings of CT at admission (n = 156) and of surgery (n = 1) revealed no evidence of hemoperitoneum in 157 (34%) patients with abdominal visceral injury; 26 (17%) of whom also had negative FAST studies. Abdominal visceral injuries diagnosed in patients without hemoperitoneum included 57 (27%) of 210 splenic injuries, 71 (34%) of 206 hepatic injuries, 30 (48%) of 63 renal injuries, four (11%) of 35 mesenteric injuries, and two (29%) of seven pancreatic injuries. Surgical and/or angiographic intervention was required in 26 (17%) patients without hemoperitoneum. CONCLUSION: Reliance on the presence of hemoperitoneum as the sole indicator of abdominal visceral injury limits the value of FAST as a screening diagnostic modality for patients who sustain blunt abdominal trauma.     

CT diagnosis of renal artery injury caused by blunt abdominal trauma

Controversy exists about the sensitivity of CT in the diagnosis of occlusion of the renal artery or one of its branches after blunt abdominal trauma. We report 10 cases in which contrast-enhanced CT was used to diagnose correctly either main (seven cases) or segmental (three cases) posttraumatic renal artery occlusion. The abnormality was proved angiographically and/or surgically in all cases. CT showed the absence of a nephrogram in the devascularized portion of the kidney in all 10 cases. A pyelogram was not shown on CT in the seven patients in whom the main renal artery was occluded, but was present in the three patients who had segmental arterial lesions. Termination of enhancement within the affected artery (renal artery cutoff sign) was observed in one patient, and a thin, peripheral rim of cortical enhancement in an otherwise unenhanced renal segment (rim sign) was observed in three patients. Retroperitoneal hematoma with renal displacement was present in nine patients. Our experience suggests that the absence of a nephrogram on contrast-enhanced CT scans is a useful sign of main or segmental renal arterial occlusion in patients with blunt abdominal trauma.     

Using contrast-enhanced helical CT to visualize arterial extravasation after blunt abdominal trauma: incidence and organ distribution.

OBJECTIVE: We evaluated the incidence and organ distribution of arterial extravasation identified using contrast-enhanced helical CT in patients who had sustained abdominal visceral injuries and pelvic fractures after blunt trauma. SUBJECTS AND METHODS: Five hundred sixty-five consecutive patients from four level I trauma centers who had CT scans showing abdominal visceral injuries or pelvic fractures were included in this series. The presence or absence of arterial extravasation, as well as the anatomic sites of arterial extravasation, was noted. We obtained clinical follow-up data, including surgical or angiographic findings. RESULTS: In our series, 104 (18.4%) of 565 patients had arterial extravasation. Of the 104 patients, 81 (77.9%) underwent surgery, embolization, or both. The combined rate of surgery or embolization in patients with arterial extravasation was statistically higher than expected at all four institutions (p <0.001). The spleen was the most common organ injured, occurring in 277 (49.0%) of 565 patients, and arterial extravasation occurred in 49 (17.7%) of 277 patients with splenic injury. Several other visceral injuries were associated with arterial extravasation, including hepatic, renal, adrenal, and mesenteric injuries. CONCLUSION: Based on the limited reports of arterial extravasation in the nonhelical CT literature, the percentage (18%) of clinically stable patients in our study with CT scans showing arterial extravasation was higher than anticipated. This finding likely reflects the improved diagnostic capability of helical CT. Although the spleen and liver were the organs most commonly associated with arterial extravasation, radiologists should be aware that arterial extravasation may be associated with several other visceral injuries.     

嗜铬细胞瘤的多层螺旋CT诊断

目的探讨多层螺旋CT(MSCT)双期扫描对嗜铬细胞瘤的诊断价值。方法分析经手术病理证实的嗜铬细胞瘤25例CT双期扫描征象。结果 CT扫描显示,嗜铬细胞瘤发生于肾上腺者22例,异位者3例,多是单侧发病(21/22)。肿块较大,边界清楚,多为类圆形或椭圆形(20例)。肿块内密度多不均,出血、坏死常见(13/25),1例坏死严重。钙化较少见,增强扫描肿瘤实体部分明显强化。结论 MSCT双期扫描对嗜铬细胞瘤的定位、定性诊断有重要价值,并且可以显示肿瘤与周围组织结构、血管的关系,有助手术方案的选择和术后随访。     

钝性肝脾肾损伤的CT平扫与增强扫描比较

目的:比较CT平扫与增强扫描对肝脾肾钝性损伤的诊断能力。方法:回顾性分析临床疑似钝性肝脾肾损伤,并经手术和临床观察证实的CT平扫和增强扫描的患者84例。结果:平扫确定的损伤:肝12例,脾25例,肾5例;平扫可疑损伤:肝22例,脾15例,肾5例。增强确定的损伤:肝32例,脾40例,肾12例(全肾梗塞1例,局限性梗塞3例);对比剂外溢(活动性出血)3例;无可疑损伤。平扫无异常而增强确定有损伤:肝10例,脾5例,肾2例。增强显示的损伤灶比平扫范围明显大、病灶多、界限清楚。结论:CT增强扫描显示肝脾肾损伤明显优于平扫,延时扫描有助于发现活动性出血,应常规增强扫描。     

Blunt abdominal trauma: does the use of a second-generation sonographic contrast agent help to detect solid organ injuries?

OBJECTIVE: The objective of our study was to prospectively evaluate whether a second-generation sonography contrast agent (SonoVue) can improve the conspicuity of solid organ injuries (liver; spleen; or kidney, including adrenal glands) in patients with blunt abdominal trauma. SUBJECTS AND METHODS: Two hundred ten consecutive hemodynamically stable trauma patients underwent both abdominal sonography and CT at admission. The presence of solid organ injuries and the quality of sonography examinations were recorded. Patients with false-negative sonography findings for solid organ injuries in comparison with CT results underwent control sonography. If a solid organ injury was still undetectable, contrast-enhanced sonography was performed. Findings of admission, control, and contrast-enhanced sonograms were compared with CT results for their ability to depict solid organ injuries. Contrast-enhanced sonography was also performed in patients in whom a vascular injury (pseudoaneurysm) was shown on admission or control CT. RESULTS: CT findings were positive for 88 solid organ injuries in 71 (34%) of the 210 patients. Admission, control, and contrast-enhanced sonograms had a detection rate for solid organ injury of 40% (35/88), 57% (50/88), and 80% (70/88), respectively. The improvement in the detection rate between control and contrast-enhanced sonography was statistically significant (p = 0.001). After exclusion of low-quality examinations, contrast-enhanced sonography still missed 18% of solid organ injuries. Five vascular liver (n = 1) and spleen (n = 4) injuries (pseudoaneurysms) were detected on CT; all were visible on contrast-enhanced sonography. CONCLUSION: Contrast-enhanced sonography misses a large percentage of solid organ injuries and cannot be recommended to replace CT in the triage of hemodynamically stable trauma patients. However, contrast-enhanced sonography could play a role in the detection of pseudoaneurysms.     

Imaging of renal trauma

Trauma is a major cause of death and disability and renal injuries occur in up to 10% of patients with significant blunt abdominal trauma. Patients with penetrating trauma and hematuria, blunt trauma with shock and hematuria, or gross hematuria warrant imaging of the urinary tract specifically and CT is the preferred modality. If there is significant perinephric fluid, especially medially, or deep laceration, delayed images should be obtained to evaluate for urinary extravasation. Most renal injuries are minor, including contusions, subcapsular and perinephric hematoma, and superficial lacerations. More significant injuries include deep lacerations, shattered kidney, active hemorrhage, infarctions, and vascular pedicle and UPJ injuries. These injuries are more likely to need surgery or have delayed complications but may still often be managed conservatively. The presence of urinary extravasation and large devitalized areas of renal parenchyma, especially with associated injuries of intraperitoneal organs, is particularly prone to complication and usually requires surgery. Active hemorrhage should be recognized because it often indicates a need for urgent surgery or embolization to prevent exsanguination.     

Computed tomography in blunt abdominal trauma: an analysis of clinical management and radiological findings.

We have retrospectively assessed the computed tomography (CT) findings in 92 patients suffering severe blunt abdominal trauma. Surgical findings and clinical follow-up were correlated with the CT findings. In nine patients CT was first used after emergency surgery and provided baseline data which was useful for further management. In two patients CT did not demonstrate small hepatic lacerations seen during previous surgery. No deaths were recorded. In 16 patients surgery followed CT within 24 h; there was good correlation between the CT and operative findings in 10 patients. However, CT failed to detect significant solid organ injury in five patients and was misleading (false positive) in another patient. There were two deaths amongst these 16 patients. Sixty-seven haemodynamically stable patients were initially managed non-operatively. Fifteen of these 67 patients had normal CT examinations; only one had subsequent laparotomy (for reasons unconnected with the trauma) where no injury was detected; there were no deaths. Of the 52 patients with an abnormal CT examination, 43 were successfully managed non-operatively. There were three deaths, including one where an injury missed at CT contributed to the demise of the patient. After an initial trial of non-operative management, the remaining six patients went to surgery where there was good concordance with the CT findings except for one missed renal injury. Active non-operative management of blunt abdominal trauma is widely accepted in haemodynamically stable patients and this report shows how CT supports this policy of surgical restraint in such cases. However, on review CT missed 13 injuries in nine patients overall; stricter attention to technique and better equipment may lead to improved results in the future.     

The trauma concept: the role of MDCT in the diagnosis and management of visceral injuries

The imaging concept in the acute trauma victim includes abdominal ultrasonography during initial triage, and contrast-enhanced computed tomography (CT) for further assessment of visceral organ injuries and active bleeding sites if haemodynamic stability can be established during initial resuscitation. Integration of modern multidector CT (MDCT) scanners in the emergency admission area greatly facilitates initial assessment of the extent of injuries in all body regions, and is therefore the emerging standard in all major centres involved in acute trauma care. Initial assessment of visceral injuries by means of CT not only allows determining the presence and extent of organ injuries and detecting active bleeding sources that may require transarterial embolisation for haemostasis, but also serves as a baseline for monitoring of conservative treatment. Specific indications for CT monitoring of conservative treatment exist in each individual organ. This concept enables the vast majority of blunt injuries of the parenchymal abdominal organs in the haemodynamically stable trauma victim to be managed without surgery.     

The significance of hematuria in children after blunt abdominal trauma

The clinical significance of hematuria in children who sustain blunt abdominal trauma continues to be debated, as do the criteria for diagnostic imaging in this population. Previous reports have discussed the usefulness of certain clinical predictors of renal injury, such as the amount of hematuria present, the presence of shock or of head injury, and the presence or absence of symptoms or findings on physical examination. To assess the value of such predictors of renal injury in children with posttraumatic hematuria, we reviewed and analyzed the medical records and abdominal CT examinations of 256 children with blunt abdominal trauma. One hundred six children (41%) had hematuria. Thirty-five patients (14%) had renal injury that could be diagnosed by using CT. Nine of these had clinically significant injuries according to our criteria. We found a direct relationship between the amount of hematuria and the severity of renal injury. Hypotension at presentation occurred in 38 patients and was an insensitive predictor of renal injury. The combination of hypotension and hematuria was no more sensitive than hematuria alone in predicting renal injury. Sixty patients had concomitant craniofacial injuries. This subgroup had the same prevalence of hematuria and renal injury as the group that did not have head injuries. There were no clinically occult renal injuries in the study population. Furthermore, we found that no normotensive child with fewer than 50 RBCs per high-power field had a significant renal injury, and conversely, all children with significant renal injuries had either large amounts of hematuria or shock.     

闭合性肾损伤的诊治分析(附32例报告)

目的 探讨闭合性肾损伤的诊断及治疗。方法 对32例闭合性肾损伤病例的临床表现及诊治方法进行分析。结果 32例病人中30例出现血尿。5例行大剂量IVU检查,3例有异常发现。10例行CT检查均发现异常。27例行保守治疗,除1例死于脑损伤外,余全部治愈。手术探查5例,肾脏仅为挫伤2例,肾裂伤行修补术2例,1例肾粉碎伤行肾切除。结论 肾损伤后血尿为主要临床表现。IVU及CT为主要的诊断手段。治疗方法的选择应根据肾损伤后血流动力学变化以有有无合并症决定。     

Kontrastmittelsonographie beim stumpfen Bauchtrauma

With the introduction of second generation ultrasound contrast agents, contrast-enhanced ultrasound (CEUS) has become available as an adjunct to the conventional FAST (focused assessment with sonography in trauma) protocol and B-mode sonography of the abdomen after blunt force abdominal trauma. Results from several controlled studies indicate excellent diagnostic accuracy of CEUS for the exclusion of clinically relevant parenchymal injuries after blunt force abdominal trauma. Particularly in younger, hemodynamically stable patients this technique could contribute to a reliable exclusion of parenchymal injuries without the use of ionizing radiation. This report provides details on the technical performance of CEUS, shows examples of typical CEUS findings after blunt abdominal trauma and summarizes the current clinical evidence regarding the use of CEUS after blunt abdominal trauma.     

Blunt bowel and mesenteric trauma: role of clinical signs along with CT findings in patients’ management

Background

Bowel and/or mesentery injuries represent the third most common injury among patients with blunt abdominal trauma. Delayed diagnosis increases morbidity and mortality. The aim of our study was to evaluate the role of clinical signs along with CT findings as predictors of early surgical repair.

Material and methods

Between March 2014 and February 2017, charts and CT scans of consecutive patients treated for blunt abdominal trauma in two different trauma centers were reread by two experienced radiologists. We included all adult patients who underwent contrast-enhanced CT of the abdomen and pelvis with CT findings of blunt bowel and/or mesenteric injury (BBMI). We divided CT findings into two groups: the first included three highly specific CT signs and the second included six less specific CT signs indicated as “minor CT findings.” The presence of abdominal guarding and/or abdominal pain was considered as “clinical signs.” Reference standards included surgically proven BBMI and clinical follow-up. Association was evaluated by the chi-square test. A logistic regression model was used to estimate odds ratio (OR) and confidence intervals (CI).

Results

Thirty-four (4.1%) out of 831 patients who sustained blunt abdominal trauma had BBMI at CT. Twenty-one out of thirty-four patients (61.8%) underwent surgical repair; the remaining 13 were treated conservatively. Free fluid had a significant statistical association with surgery (p?=?0.0044). The presence of three or more minor CT findings was statistically associated with surgery (OR?=?8.1; 95% CI, 1.2–53.7). Abdominal guarding along with bowel wall discontinuity and extraluminal air had the highest positive predictive value (100 and 83.3%, respectively).

Conclusion

In patients without solid organ injury (SOI), the presence of free fluid along with abdominal guarding and three or more “minor CT findings” is a significant predictor of early surgical repair. The association of bowel wall discontinuity with extraluminal air warrants exploratory laparotomy.

     

The value of non-contrast-enhanced CT in blunt abdominal trauma

The usefulness of non-contrast CT, limited to the upper abdomen, in conjunction with conventional IV contrast-enhanced scanning was studied prospectively in 190 patients who had sustained blunt abdominal trauma. In 78, visceral injuries were confirmed at surgery or at follow-up CT. Of the patients with injuries, 14 (18%) had hyperdense hematomas on the non-contrast studies that became isodense after IV administration of contrast material. These hematomas generally were small and posed an immediate threat to life in only one patient (0.5% of all subjects). In 13% of patients with injury (5% of the total), the additional information did influence treatment planning (surgery in two and intensive conservative treatment in eight). Compared with conventional contrast scanning, the combined non-contrast-contrast technique increased the scanning time only by about 5 1/2 min, but it improved the sensitivity and accuracy of CT in detecting visceral injuries from 74% and 84% to 92% and 91%, respectively (p less than or equal to .003 and p less than or equal to .04). Although contrast-enhanced scanning alone accurately depicts visceral injuries requiring surgical treatment, the incorporation of a non-contrast sequence can detect a subgroup of patients who require intensive conservative management with bed rest and close observation. This additional information can be obtained expeditiously, with minimal additional effort or intervention. The use of non-contrast scanning alone is not recommended.     

Bowel and mesenteric injury following blunt abdominal trauma: evaluation with CT

Computed tomography (CT) used in cases of blunt abdominal trauma has been found sensitive in detection of bowel and mesenteric injuries and discrimination of operable from nonoperable candidates. In 51 patients with suspected bowel or mesenteric injury following blunt abdominal trauma, CT correctly depicted bowel hematoma or mesenteric injury in 17 of 19 nonoperable patients (89%) and severe injuries in one patient who died preoperatively. In 26 of 28 patients who underwent therapeutic laparotomy (93%), initial CT enabled identification of surgically confirmed injuries. In two cases, initial scan misinterpretation delayed diagnosis of serious bowel injuries. The correct interpretation was rendered preoperatively and at blind retrospective review. CT findings that correlated with bowel or mesenteric injury requiring surgery were free peritoneal fluid (27 of 28, 96%), mesenteric infiltration (24 of 28, 86%), thick-walled bowel (17 of 28, 61%), associated abdominal injuries (12 of 28, 43%), and free air (nine of 28, 32%). In nonoperable cases, CT scans demonstrated bowel thickening (84%) but less frequently peritoneal fluid (21%), mesenteric infiltration (26%), or associated injuries (5%). In three of four patients who underwent nontherapeutic laparotomy, preoperative CT correctly imaged the limited abdominal injuries.     

Evaluation of abdominal trauma by computed tomography

Computed tomography (CT) was used in the evaluation of 100 patients suffering abdominal trauma. The type of trauma was blunt in 78 patients, penetrating in eight, and iatrogenic in 14. Forty per cent of cases had normal CT scans, while 60% showed substantial abdominal or retroperitoneal injuries. Surgery, clinical follow-up, and repeated radiologic examinations confirmed the accuracy of CT, and there were no cases in which medical or surgical management was inappropriately guided by CT. A wide variety of injuries was detected, including 19 splenic, eight hepatic, six pancreatic, 13 renal, 13 retroperitoneal or abdominal wall, and one intraperitoneal. CT has major advantages over plain radiography, radionuclide imaging, and angiography in assessment of trauma-induced injuries.     

Gallbladder blunt trauma: comparison between radiologic and anatomo-surgical findings

PURPOSE: To assess the diagnostic accuracy and the possible role of ultrasonography (US) and Computed Tomography (CT) in a small group of patients who had a blunt abdominal trauma involving the gallbladder. MATERIAL AND METHODS: We retrospectively reviewed the US and CT findings of five patients with surgically confirmed post-traumatic gallbladder injury. The whole series consisted of 196 consecutive patients submitted to laparotomy for blunt abdominal trauma in the past 7 years. The following US and CT findings were considered at least suggestive of a possible post-traumatic gallbladder injury: pericholecystic fluid collection, ill-defined wall margin, collapsed lumen, high intraluminal density. RESULTS: At surgery, the following findings were observed: gallbladder hematoma (1 case), acute colecystitis (1 cases), gallbladder tear (3 cases), gallbladder tear associated with post-traumatic hepatic injuries (2 cases), duodenal tear (2 cases), hemoperitoneum alone (2 cases), hemoperitoneum associated with choleperitoneum (1 case), choleperitoneum alone (1 case). The US and CT findings were pericholecystic fluid collections (4 cases), ill-defined gallbladder wall margins (3 cases), collapsed lumen with intraluminal high density (1 case) and free intraperitoneal fluid collections (4 cases). They were suggestive of a possible post-traumatic gallbladder injury in all the five patients. CONCLUSIONS: The radiologic findings of our five patients were suggestive of a gallbladder damage but did not permit to distinguish minor from major injuries, the latter requiring surgical treatment. US proves to be a useful screening tool which can also help timing surgery in these patients. CT confirmed the US suspicions and also permitted accurate assessment of associated post-traumatic injuries to the liver and duodenum. Nevertheless, the clinical presentation was the most important factor as to the therapeutic management of these blunt abdominal trauma patients.     

Value of contrast-enhanced CT for managing mesenteric injuries after blunt trauma: review of five-year experience

Objective: The purpose of this retrospective study was to determine the value of contrast-enhanced computed tomography (CT) in the detection and management of mesenteric injuries after blunt trauma. Materials and methods: Between June 1995 and December 2000, 1,619 consecutive abdominal CT examinations were performed in the setting of major blunt trauma. Findings at CT were evaluated before patients were classified as having grade 1 or grade 2 lesions or none. Grade 1 represented the presence of minor injuries: mesenteric haziness, confined fluid, and/or small hematomas (<30 mm) within the mesenteric folds and abdominal injuries; grade 2 was appropriate to evidence of major injuries: moderate to large hematomas (>30 mm), active bleeding, hemoperitoneum, and further abdominal injuries. Results: On the basis of the CT findings, 161 (9.9%) of 1,619 patients were classified as having grade 1 and 25 (1.5%) of 1,619 patients as having grade 2 injuries. Of the 161 (77.6%) patients with grade 1 injuries, 125 were managed conservatively, while 36 (22.4%) underwent surgery. Of the 25 (84%) patients with grade 2 injuries, 21 were treated surgically and 1 (4%) patient was followed medically. Three (12%) of the 25 patients underwent laparotomy after 24 h close clinical observation and monitoring. Initial CT findings in 1,433 (88%) of the 1,619 patients were negative for mesenteric injuries, and in 1,430 of these cases no delayed mesenteric hemorrhage was observed. Conclusion: Contrast-enhanced CT has a critical role in the identification and exclusion of mesenteric injuries. Persistent, active extravasation of contrast material, in isolation or associated with further abdominal lesions, is a sign of a high likelihood of injury requiring urgent laparotomy. Haziness, isolated confined clotted mesenteric hemorrhage, and small hematomas within the mesentery are nonspecific findings and should be considered in the appropriate clinical context. Close clinical observation, monitoring, and surgical expertise are mandatory for appropriate management. Electronic Publication     

Early ureteral luminal enhancement on computed tomography in a renal trauma patient: a characteristic sign of communication between artery and collecting system

We report the case of a 65-year-old man with blunt abdominal trauma following a fall from a three-meter-high roof. Contrast-enhanced abdominal computed tomography (CT) obtained in early phase showed intense contrast enhancement in the urinary tract as dense as artery. This finding was considered characteristic of traumatic communication between artery and collecting system. In cases of blunt abdominal trauma, contrast-enhanced CT should be obtained in the early phase to diagnose this disorder. When the diagnosis is made, prompt treatment should be initiated.