Presence of an accessory spleen in the gastrosplenic ligament: Its histological observation and clinical consequences

Jyothsna Patil; Naveen Kumar; Satheesha B Nayak; S Swamy Ravindra; Anitha Guru; Ashwini P Aithal; Melanie R D'Souza

doi:10.4103/2348-3334.153266

CASE REPORT

Year : 2015 | Volume : 2 | Issue : 2 | Page : 163-165

Presence of an accessory spleen in the gastrosplenic ligament: Its histological observation and clinical consequences

Jyothsna Patil, Naveen Kumar, Satheesha B Nayak, S Swamy Ravindra, Anitha Guru, Ashwini P Aithal, Melanie R D'Souza
Department of Anatomy, Melaka Manipal Medical College (Manipal Campus), Manipal University, Manipal, Karnataka State, India

Date of Web Publication

16-Mar-2015

Correspondence Address:
Naveen Kumar
Department of Anatomy, Melaka Manipal Medical College (Manipal Campus), Manipal University, Manipal - 576 104, Karnataka
India

Source of Support: None, Conflict of Interest: None

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DOI: 10.4103/2348-3334.153266

Abstract

Accessory or supernumerary spleens are congenital in occurrence. Its presence may result in differential diagnosis or exhibit continued symptoms after therapeutic splenectomy. We report here a case of accessory spleen (AS), which was remarkably larger in size was found within the gastro-splenic ligament, adherent to its anterior layer. It received an independent vascular supply from splenic vessels supplying the main spleen (MS). Its histological architecture was in close resemblance to that of MS, but with the deficiency of white pulp. Failure to remove AS during main splenectomy done for pathological conditions may result in failure of resolving the condition due to which the pathological condition persists. Occurrence of ASs may also be confused for enlarged lymph nodes or neoplastic growth in the tail of pancreas, gastrointestinal tract and adrenal glands.

Keywords: Accessory spleen, histology, supernumerary spleen, white pulp

How to cite this article:
Patil J, Kumar N, Nayak SB, Ravindra S S, Guru A, Aithal AP, D'Souza MR. Presence of an accessory spleen in the gastrosplenic ligament: Its histological observation and clinical consequences. CHRISMED J Health Res 2015;2:163-5

How to cite this URL:
Patil J, Kumar N, Nayak SB, Ravindra S S, Guru A, Aithal AP, D'Souza MR. Presence of an accessory spleen in the gastrosplenic ligament: Its histological observation and clinical consequences. CHRISMED J Health Res [serial online] 2015 [cited 2022 May 23];2:163-5. Available from: https://www.cjhr.org/text.asp?2015/2/2/163/153266

Introduction

An accessory spleen (AS), also known as supernumerary spleen is generally a small nodule of splenic tissue found distant from the main spleen (MS). AS is a congenital nodule with the usual feature as that of the main splenic tissue. They develop from the side of the dorsal mesogastrium as a result of inadequate fusion of splenic lobules. ^[1] In the majority of the cases (85%) of its occurrence, single AS is seen. However, rarely, there may be two (14%) and three or more (1%) ASs. The size of the AS is reported to be not more than 2 cm in diameter. ^[2]

They are mostly located near the MS within the gastrosplenic ligament (30%). Rarely, they are found at the tail of pancreas, greater omentum, mesentery of the small intestine, stomach, kidney and with an exceptional position in scrotum. ^[3] Due to its uncertain location, it often misleads the clinicians during interventional procedures and the radiologists during reporting.

Case report

While performing dissection of the abdomen for the medical undergraduate students and demonstrating peritoneal ligaments, we observed a hard, dark, well-circumscribed oval mass within the gastrosplenic ligament. It was found attached to the anterior layer of the gastrosplenic ligament, at the vicinity of the visceral surface of the spleen [Figure 1]a and b. The mass was measuring 4 cm in diameter and weighed 5.5 g. The histological examination revealed the presence of splenic tissue. However, the white pulp population was deficit [Figure 2]. We also noted the prominent vascular pattern of AS, which was derived from the vessels of the MS. This prominent AS was noted in the male corpse aged about 60 years. The MS was found to be normal in size and morphology.

Figure 1: (a) Accessory spleen (AS) at the vicinity of main spleen (MS) and its vascular pattern (VAS) from splenic vessels (SV) of MS. (b) Closer view of AS situated in relation to visceral surface of MS

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Figure 2: Histological photomicrograph of accessory spleen. RP: Red pulp, TA: Trabecular artery, C: Capsule (insight) (H and E, ×20)

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Discussion

Presence of an AS is usually asymptomatic as long as its location is confined to the abdomen. Occasionally, its pedicles may undergo torsion and result in infarction and rupture with the indications of hematologic symptoms associated with abdominal pain. This warrants laparoscopic resection of the AS. ^[4] Even though the presence of an AS is asymptomatic, when they are incidentally discovered during laparoscopic surgery; it is advisable to perform laparoscopic splenectomy as it may cause high risk of torsion in the future. ^[5] After resection of proper spleen, ASs may increase significantly and also enhances the risk of interpretation as secondaries in radiological examinations. ^[6]

Occurrence of AS often misleads to differential diagnosis during radiological interpretations. It has been observed as a soft tissue mass at the neighborhood of the upper pole of left kidney while performing intravenous pyelography to be suspected it as adrenal tumor. Later, while in computed tomography (CT) it was diagnosed as an AS and further confirmation was done by abdominal angiography. ^[7] A case of an AS mimicking the adrenal carcinoma has been reported. ^[5] An intra-pancreatic AS observed during CT of abdomen and pelvis as lesion in the tail of the pancreas was reported. ^[8] Based on the studies of CT features of AS, its prevalence has been reported to be 15.6%. Among this incidence, more than one AS has been observed in about 13% cases. ^[9]

It is interesting to note the association of incidence of poly splenia with cardiovascular and pulmonary abnormalities in some patients. ^[10] Unusually large AS is a rare occurrence. Its presence may require surgical intervention and detailed anatomic structure can be obtained by magnetic resonance imaging. However, for the smaller AS, damaged red blood cell scintigraphy is said to be specific confirmation marker. ^[4]

In the current case, the AS was a remarkably large mass and found to be present within the gastrosplenic ligament in close approximation with the visceral surface of the MS. To further probe into the matter, a histological examination was done. Microscopic architecture of AS was fairly similar to that of the MS, except in its white pulp. AS showed the prominent connective tissue capsule and the septae as seen in MS. The lymphatic nodules of the white pulp were ill-defined. The red pulp population was significantly predominating with the abundant number of lymphocytes arranged in the form of splenic cords of Billroth. Numerous trabecular arteries were seen. This shows, the AS was richly supplied by the artery, but functionally it might not be as effective in its immune responsibility as the MS due to lack of white pulp.

To conclude, occurrence of remarkably large AS that we reported herewith is rare. Persistence of such exceptional AS often misleads during the interpretations of imaging techniques as peritoneal metastasis, lymph node enlargement, tumor of the tail of pancreas, renal tumor recurrence post nephrectomy or adrenal mass, etc., Presence of ASs makes obligatory to the surgeons to remove all functional splenic tissue during the surgical treatment for hematologic disorders.

References

1.	Halpert B, Gyorkey F. Lesions observed in accessory spleens of 311 patients. Am J Clin Pathol 1959;32:165-8.
2.	Keisam AD, Laitonjam C. Accessory spleen-A case report with a brief review. J Evol Med Dent Sci 2014;3:1859-63.
3.	Gayer G, Zissin R, Apter S, Atar E, Portnoy O, Itzchak Y. CT findings in congenital anomalies of the spleen. Br J Radiol 2001;74:767-72.
4.	Velanovich V, Shurafa M. Laparoscopic excision of accessory spleen. Am J Surg 2000;180:62-4.
5.	Chen CH, Wu HC, Chang CH. An accessory spleen mimics a left adrenal carcinoma. MedGenMed 2005 5;7:9.
6.	d′Amico A, Cofalik A, Przeorek C, Gawlik T, Olczyk T, Kalemba M, et al. Role of nuclear medicine imaging in differential diagnosis of accessory spleens in patients after splenectomy. Pol J Radiol 2012;77:68-71.
7.	Stiris MG. Accessory spleen versus left adrenal tumor: Computed tomographic and abdominal angiographic evaluation. J Comput Assist Tomogr 1980;4:543-4.
8.	George M, Evans T, Lambrianides AL. Accessory spleen in pancreatic tail. J Surg Case Rep 2012;2012.
9.	Mortelé KJ, Mortelé B, Silverman SG. CT features of the accessory spleen. AJR Am J Roentgenol 2004;183:1653-7.
10.	Vanbeckevoort D, Verswijfel G, Van Hoe L. Congenital disorders of the spleen. In: De Schepper AM, Vanhoenacker F, editors. Medical Imaging of the Spleen. Berlin, Germany: Springer-Verlag; 2000. p. 19-28.