Accessory Spleen Fracture: Report of a Pediatric Case and Review of the Literature

(1)

Article

Reference

Accessory Spleen Fracture: Report of a Pediatric Case and Review of the Literature

CHAUVET, Eline, et al.

Abstract

Accessory spleen rupture may occur after blunt abdominal trauma or, more rarely, spontaneously. Although only few cases are described in adults, it is even more uncommon in children. We report the case of a 13-year-old boy with traumatic accessory spleen fracture.

After a review of the literature, we discuss the diagnostic points that should raise the suspicion for accessory spleen fracture as well as how challenging the diagnosis by computed tomography can be.

CHAUVET, Eline, et al . Accessory Spleen Fracture: Report of a Pediatric Case and Review of the Literature. Pediatric Emergency Care , 2017

DOI : 10.1097/PEC.0000000000001381 PMID : 29298250

Available at:

http://archive-ouverte.unige.ch/unige:128091

Disclaimer: layout of this document may differ from the published version.

(2)

Accessory Spleen Fracture

Report of a Pediatric Case and Review of the Literature

Eline Chauvet, MD, Vasiliki Spyropoulou, MD, Mehrak Anooshiravani-Dumont, MD, Oliver Sanchez, MD, and Laurence Lacroix, MD

Abstract:Accessory spleen rupture may occur after blunt abdominal trauma or, more rarely, spontaneously. Although only few cases are described in adults, it is even more uncommon in children. We report the case of a 13-year-old boy with traumatic accessory spleen fracture. After a review of the literature, we discuss the diagnostic points that should raise the suspicion for accessory spleen fracture as well as how challenging the diagnosis by computed tomography can be.

Key Words:accessory spleen, spleen fracture, abdominal trauma (Pediatr Emer Care2017;00: 00–00)

B

lunt abdominal trauma (BAT) accounts for 80% of abdominal injuries in adults.¹In children, intra-abdominal organ injury is diagnosed in 5% to 10% of all BAT.²Spleen and liver are the most frequently injured organs, but other structures such as an accessory spleen, which is present in 10% to 30% of the population according to necropsies,³should also be considered. The origin of an accessory spleen relates to the embryologic development of the spleen itself. Indeed, it results from failure of spleen precursor cells to fuse in the dorsal mesogastrium,³resulting in the presence of 1, rarely more, accessory spleen(s). This organ may rupture, sometimes spontaneously, or as more frequently reported as a re- sult of an abdominal trauma. However, rupture of an accessory spleen is rarely encountered in children and too few cases have been reported to precisely evaluate its incidence and prevalence in the pediatric population. We hereby present the case of a traumatic accessory spleen rupture in a child to remind the emergency physician about this rarely encountered but life-threatening differential diagnosis.

CASE

A previously healthy 13-year-old boy presented to the pediatric emergency department with acute abdominal pain. Six hours before admission, he had fallen off his kick-scooter (with no pre- cise information on velocity), with direct impact of the handlebar onto the abdomen, but no immediate abdominal complaint. A few hours later, he presented with pelvic pain on urination but no gross hematuria. On examination, general appearance and perfusion were normal; heart rate was 98/min; and blood pressure was 127/76 mmHg, with otherwise unremarkable respiratory examination. Abdominal examination revealed diffuse tenderness with rebound tenderness in the right lower quadrant and the epigastric region. Laboratory tests revealed a lower range hemoglobin count of 125 gram/litre (normal, 130–160 gram/litre) and normal white blood cell count (11.4 giga/litre). Blood gases, serum electrolytes, liver and pancreas function tests, blood clotting tests, and urinalysis

were normal. Abdominal ultrasonography showed a significant amount of free high-density intraperitoneal fluid suggesting the presence of a hemoperitoneum. Intravenous fluid maintenance ther- apy was started, and the patient remained hemodynamically stable.

According to our local guidelines based on ATLS current rec- ommendations,⁴further investigations included an immediate low-dose contrast-enhanced abdominal computed tomography (CT) scan, which confirmed the presence of a hemoperitoneum with no clear evidence of solid organ injury or abdominal wall trauma. The patient was admitted to the pediatric intensive care unit for medical supervision and continuous monitoring.

Twenty-four hours later, a second higher resolution CT scan was performed to precisely determine the origin of the hemorrhage. It allowed the detection of a small rounded structure just below the lower pole of the spleen, with partial hypodensity after contrast enhancement, suggestive of a ruptured small accessory spleen (Fig. 1). However, there was no sign of active bleeding at that stage (ie, no contrast extravasation).

The patient underwent conservative management with a 4-day strict bed rest. He started refeeding after 48 hours and was discharged after 5 days.

At 1 month follow-up, he had no residual symptoms. There was no tenderness or mass on abdominal examination. The abdominal ultrasound was repeated, showing a homogenous spleen with no residual free fluid but a residual hematoma on the inferior pole of the accessory spleen.

DISCUSSION

Although BAT is frequent in pediatric emergency practice and may occasionally be associated with abdominal hemorrhage due to organ damage, traumatic rupture of an accessory spleen has rarely been reported in children and is therefore often

From the Pediatric Department, Hôpitaux Universitaires de Genève, Genève, Switzerland.

Disclosure: The authors declare no conflict of interest.

Reprints: Eline Chauvet, MD, 93 Chemin du Gué 1213, Petit-Lancy, Switzerland (e‐mail: eline.chauvet@gmail.com).

ISSN: 0749-5161

FIGURE 1. Contrast-enhanced CT showing a small rounded structure located below the lower pole of the spleen with surrounding fluid collection, suggesting a ruptured accessory spleen with no active bleeding.

(3)

forgotten. A systematic review of the literature identified only 10 reported cases of accessory spleen fracture in patients with no un- derlying disease, most of them involving adults (Table 1). Only 1 of them was a child aged 8 years old.⁵

Accessory spleen rupture is most often due to direct traumatic injury, often associated with BAT,⁵^–⁹sometimes even in minor traumatic events.^5,9However, spontaneous rupture of an accessory

spleen has also been reported in otherwise healthy subjects,¹⁰^–¹⁴ without any evidence of previous trauma. Most of these patients presented with acute abdominal pain,¹²^–¹⁴but initial progressive pain was also described, with 1 patient waiting up to 6 weeks before seeking medical assistance.^10,11 Only very few cases are mentioned in the literature, and there is to our knowledge no data about associated mortality.

TABLE 1. Case Reports of Traumatic and Spontaneous Rupture of Accessory Spleen

Case Number

Adult/Child, sex Age, y

Spontaneous or Traumatic

Rupture History

Delay Between Trauma or Pain Onset

and Presentation

Hemodynamics at Presentation

1 Adult, M Unknown T Cyclist knocked over by a car,

pain in LUQ

Immediate Unstable

2 Adult, M 32 T Struck in LUQ while running

during a baseball game

1 d Stable

3 Child, M 8 T Slipping in bathroom with trauma

to lower left hemithorax

1 d Stable

4 Adult, M 19 T Struck in LUQ during a hockey game Immediate Stable

5 Adult, F Unknown T Fall against corner of dresser with direct impact to LUQ

Immediate Stable

6 Adult, F 50 S Sudden onset of generalized abdominal

pain with progressive migration to left hemiabdomen

5 d Stable

7 Adult, M 29 S Sudden intense pain in epigastrum

and LUQ

Immediate Unstable

8 Adult, M 36 S 6 wk of fatigue and abdominal pain.

Past history: at 6 y of age, splenectomy after motor vehicle accident

6 wk Stable

9 Adult, F 45 S Sudden onset of abdominal pain.

Past history of splenic rupture 25 y before, with splenectomy revealing a 2 cm accessory spleen left in place at the time

Immediate Stable

10 Adult, F 62 S Spontaneous pain in left hemiabdomen

with radiation to the back.

Past history: nephrectomy 11 y before and splenectomy 13 y before, for capsule rupture 1 y after falling off a stepladder

Immediate Stable

S, spontaneous; T, traumatic; LUQ , left upper quadrant.

Chauvet et al Pediatric Emergency Care • Volume 00, Number 00, Month 2017

2

(4)

Nowadays, in children, focused assessment with sonography for trauma echo is the immediate imaging study performed to detect intra-abdominal injury related to trauma. It allows a rapid detection of free intraperitoneal fluid suggestive of organ injury and indicates the need for prompt abdominal CT scan. However, we no- ticed that in most cases of traumatic rupture of an accessory spleen, CT scan was performed without any prior ultrasound guided mainly

by the clinical findings. Classically, CT findings included free intra- abdominal fluid, perisplenic hematoma, or fresh-clot in the left upper quadrant. In contrast, in spontaneous ruptures, ultrasound was more often performed as a first line diagnostic tool, showing free abdominal fluid^10,13or even a left upper quadrant mass.^10,12In all but 1 of the reported cases of spontaneous and traumatic rupture of accessory spleen, the lesion was initially diagnosed by an explorative Imaging Performed Radiographic Findings Diagnosis

Immediate/Delayed Surgical Management

Clinical Outcome Ultrasound Peritoneal fluid with

perisplenic hematoma

Laparotomy Immediate Not available

CT scan Free fluid in the peritoneal cavity

Laparotomy Immediate After surgery: good recovery,

discharged on day 4

None Laparotomy for suspicion of

appendicitis with peritonitis

Immediate After surgery: good recovery, discharged on day 12 CT scan Perisplenic hematoma with

laceration on inferior aspect of spleen

Laparotomy Delayed by 12 h Conservative management

until fall in hemoglobin After surgery: good recovery Abdominal x-ray and

spleen scintigraphy

Suspected splenic rupture on anterior scan but not on posterior and lateral views

Laparotomy Not available Not available

Ultrasound Free fluid and hypoechogenic mass in LUQ

Laparotomy: a second larger accessory spleen, not apparent on CT scan and angiography, was found with active bleeding from a small capsular tear.

Immediate After surgery: good recovery, discharged on day 4

CT scan Identification of an accessory spleen and a fresh clot in left upper quadrant

Angiography No bleeding identified, normal capillary blush of the accessory spleen seen on CT scan

Ultrasound Intra-abdominal free fluid Laparotomy: accessory spleen rupture due to pedicle torsion

Immediate After surgery: good recovery

Barium swallow Mass in LUQ Laparotomy Not available Not available

CT scan Large bilobed mass with focal area of high density

Ultrasound Oval mass in LUQ Laparotomy Not available Conservative management

followed by elective laparotomy upon patient's request although splenic hemorrhage had stopped After surgery: good recovery CT scan Hypertrophied accessory

spleen surrounded by fluid Technetium scan

after conservative management

No evidence of active splenic hemorrhage

CT scan Free fluid LUQ Laparoscopy converted to

laparotomy because of multiple adhesions due to past surgeries.

This revealed a ruptured accessory splenic nodule.

Not available After surgery: good recovery

Contrast-enhanced CT scan

Hematoma with central hyperdense spot suggesting active bleeding

(5)

laparotomy, and the remaining case was diagnosed on CT scan.¹²In our patient, the first CT scan confirmed the presence of free abdominal fluid but also failed to show the origin of bleeding. The second CT scan detected the lesion without any active bleeding and allowed to opt for a conservative treatment.

On CT scans, 1 or more round masses, with the same density as the spleen, located near the splenic hilum highly suggest the presence of one or several accessory spleens. After contrast enhancement, these structures show the same characteristics as the spleen itself. Active bleeding can be diagnosed by using contrast agents or angiography. In 1 case,¹⁰angiography showed a normal capillary blush of 2 little accessory spleens but failed to reveal the bleeding of a larger one, which was partially obscured by the tail of the pancreas and the spleen. In our case, the small accessory spleen was heterogeneous and partly hypodense whereas the main spleen was homogeneous after enhancement. There were no sign of active bleeding and no sign of vascular injury or any contrast extravasation.

CONCLUSIONS

Although rarely encountered, the possibility of accessory spleen rupture should be considered when confronted with free abdominal fluid and no evidence of organ rupture in patients pre- senting with BAT. In the absence of known trauma, sudden or progressive abdominal pain in a child should also raise the differential diagnosis of spontaneous accessory spleen rupture. Although the small heterogeneous injured accessory spleen can be difficult to detect on ultrasound and even CT owing to its small size and ad- jacent hemoperitoneum, awareness of this rare finding is useful in routine practice.

REFERENCES

1. Nishijima DK, Simel DL, Wisner DH, et al. Does this adult patient have a blunt intra-abdominal injury?JAMA. 2012;307:1517–1527.

2. Gaines BA. Intra-abdominal solid organ injury in children: diagnosis and treatment.J Trauma. 2009;67(suppl 2):S135–S139.

3. Curtis GM, Movitz D. The surgical significance of the accessory spleen.

Ann Surg. 1946;123:276–298.

4. American College of Surgeons Committee on Trauma. Pediatric Trauma in Advanced Trauma Life Support (ATLS) Student Course Manual.

Chicago, IL: American College of Surgeons; 2013:261.

5. Kumar R. A case of traumatic rupture of an accessory spleen.Arch Dis Child. 1962;37:227.

6. Habib E, Elhadad A. Traumatic rupture of an accessory spleen.Ann Chir.

2001;126:65–66.

7. Karam JA, Kozar RA. Solitary blunt rupture of an accessory spleen.

J Trauma. 1998;44:220–221.

8. Richmond R, Humphrey P, Nichols WK. Isolated traumatic accessory splenic rupture: a case report and literature review.Mo Med. 1992;89:

351–353.

9. Fink DW. Scintiphotographic demonstration of rupture of an accessory spleen.J Nucl Med. 1972;13:333–334.

10. Coote JM, Eyers PS, Walker A, et al. Intra-abdominal bleeding caused by spontaneous rupture of an accessory spleen: the CT findings.Clin Radiol.

1999;54:689–691.

11. Goodman P, Raval B, King FA. Spontaneous necrosis and hemorrhage in an enlarged accessory spleen: CT demonstration.Comput Med Imaging Graph. 1990;14:201–203.

12. Leon L, Labropoulos N, Hudlin CI, et al. Accessory spleen rupture in a patient with previous traumatic splenectomy.J Trauma. 2006;60:901–903.

13. Padilla D, Ramia JM, Martin J, et al. Acute abdomen due to spontaneous torsion of an accessory spleen.Am J Emerg Med. 1999;17:429–430.

14. Depypere L, Goethals M, Janssen A, et al. Traumatic rupture of splenic tissue 13 years after splenectomy. A case report.Acta Chir Belg.

2009;109:523–526.

Chauvet et al Pediatric Emergency Care • Volume 00, Number 00, Month 2017