|Year : 2021 | Volume
| Issue : 1 | Page : 12-14
A rare differential diagnosis of gluteal mass
Pandiaraja Jayabal1, Shalini Arumugam2
1 Department of General Surgery, Dr. Mehta Hospital, Tamil Nadu, India
2 Department of Community Medicine, ACS Medical College, Tamil Nadu, India
|Date of Submission||26-Dec-2020|
|Date of Decision||20-Jan-2021|
|Date of Acceptance||20-Jan-2021|
|Date of Web Publication||26-Apr-2021|
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Source of Support: None, Conflict of Interest: None
Fat necrosis is an inflammatory process of fat folloing an insult to the adipose tissue. It is more common in the body region here there is high adipose tissue. It can present ith cellulitis, skin necrosis, discharging ounds, and mass. Carcinoma is one of the differential diagnoses of fat necrosis. Our case is presented ith a gluteal mass hich as diagnosed as a hydatid cyst, based on the imaging. Sometimes, imaging fails to identify traumatic fat necrosis, particularly if it is associated ith a capsule ith multiple fat lobules. Postoperative history confirms the encapsulated type of fat necrosis ith fat lobules. Encapsulated traumatic fat necrosis should be considered one of the differential diagnoses of hydatid cyst.
Keywords: Gluteal cyst, hydatid cyst, multiple fat lobules, traumatic fat necrosis
|How to cite this article:|
Jayabal P, Arumugam S. A rare differential diagnosis of gluteal mass. J Orthop Dis Traumatol 2021;4:12-4
| Introduction|| |
The incidence of fat necrosis varies from 0.6% to 1% hich depends on the etiology of fat necrosis. As per the literature, imaging is one of the primary tools for the screening and diagnosis of fat necrosis. Sometimes, images are failed to identify fat necrosis and misdiagnosed as some other diseases. It may create difficulty to plan the current management for the patient. The most common differential diagnosis for fat necrosis of the breast is carcinoma breast. Our case as initially diagnosed as a hydatid cyst of the gluteal region based on imaging as ell as finally diagnosed as fat necrosis based on histopathological examination. This case is reported to kno about one of the differential diagnoses of fat necrosis.
| Case Report|| |
A 22-year-old female presented ith a complaint of selling in the right gluteal regions for the past 6 months. She also complained of pain in the right gluteal regions for the past 1 month. The selling has gradually increased its size. There as no history of fever and purulent discharge from the selling. She denied a history of trauma. She as not on any anticoagulant or prolonged medications. On local examination, the right gluteal regions shoed a selling measuring 12 cm × 8 cm. The selling as firm to hard in consistency. There as no regional lymphadenopathy.
The blood investigations such as complete hemogram, renal function test, liver function test, and coagulation profile (prothrombin time, activated partial thromboplastin time, international normalized ratio, bleeding time, and clotting time) ere normal. Ultrasound examination of the local region shoed an ill-defined cystic lesion of 11.5 cm × 7 cm present in the right gluteal regions. Magnetic resonance imaging (MRI) of the gluteal region shoed a capsulated cystic lesion arising from the right gluteal region, ith multiple small cysts inside the large cyst [Figure 1]. Hydatid cyst as considered one of the differential diagnoses of this patient based on the history and imaging findings.
|Figure 1: Magnetic resonance imaging of the gluteal region showing a capsulated cystic lesion arising from the right gluteal region, with multiple small cysts inside the large cyst|
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The patient underent excision under anesthesia. The intraoperative picture shoed the fibrotic capsule ith multiple fat lobules [Figure 2]. The cyst along ith fat lobules excised completely, and the ound as closed ith a suction drain. The postoperative cut open specimen shoed the thick fibrotic capsule ith multiple fat lobules along ith serous fluid [Figure 3]. Postsurgical histopathology shoed subcutaneous tissue ith fat necrosis and fat cyst. It also shoed foamy histiocytes and multinucleated foreign body giant cells [Figure 4]. There as no evidence of parasites or granuloma. Histopathology confirmed the diagnosis of fat necrosis ith the fat cyst. The patient has been folloed up for more than 1 year ithout any disease recurrence.
|Figure 2: Intraoperative picture showing the fibrotic capsule with multiple fat lobules|
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|Figure 3: Postoperative cut open specimen showing the thick fibrotic capsule with multiple fat lobules along with serous fluid|
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|Figure 4: Postsurgical histopathology showing subcutaneous tissue with fat necrosis and fat cyst. It also shows foamy histiocytes and multinucleated foreign body giant cells|
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| Discussion|| |
Posttraumatic fat necrosis is usually located beteen the subcutaneous tissue and deep fascia. It is usually filled ith serous fluid and fibrous tissue as a pseudocapsule. Fat necrosis is occurring folloing trauma, external pressure, extreme temperature, folloing injections, contrast extravasation, folloing radiotherapy, folloing anticoagulant use, folloing implant removal, and folloing invasive procedure. In trauma, fat necrosis is occurring folloing the shearing of the skin and subcutaneous tissue over the deep fascia. The shearing force of subcutaneous tissue produces liquefaction of fat and formulation of a cyst due to dense fibrous tissue formation around the cyst. As per the available evidence and literature, traumatic fat necrosis can present either encapsulated and nonencapsulated lesions.
Posttraumatic necrosis is more common in thighs, arms, breasts, and buttocks. It can present ith cellulitis, skin necrosis, discharging ound sinus, breast mass, skin retraction, and sometimes mimics like a malignancy. Our case is presented as a gluteal mass and created diagnostic confusion. The complications of the cyst may be sudden hemorrhage inside the cyst, infection of the cyst, and calcification of the cyst.
Ultrasound of fat necrosis shos areas of peripheral hyperechogenicity and central areas of hypoechogenicity. There are reports of mixed presentation of traumatic fat necrosis like hypoechogenicity and isoechogenicity. In mammography, traumatic fat necrosis sometimes appears like carcinoma breast. On MRI, it may appear as hyperintensity in both T1- and T2-eighted images.
Surgical excision is the standard of care for the large cyst or diagnosis of uncertainty. Small fat necrosis or associated ith an infection-like cellulitis can be managed ith conservative treatment. There are reports of large traumatic fat necrosis that underent ide local excision ith flap cover. Postoperative histology ill confirm the diagnosis in most of the cases. Histology shos adipose tissue ith foamy macrophages and multinucleated foreign body giant cells. There may be areas of fibrosis and calcification.
| Conclusion|| |
Traumatic fat necrosis can present ith gluteal mass ithout a history of trauma. Posttraumatic necrosis is more common in thighs, arms, breasts, and buttocks. It can present ith cellulitis, skin necrosis, discharging ounds, and mass. Sometimes, imaging fails to identify traumatic fat necrosis, particularly if it is associated ith a capsule ith multiple fat lobules. Postoperative history confirms the encapsulated type of fat necrosis ith fat lobules. Encapsulated traumatic fat necrosis should be considered one of the differential diagnoses of hydatid cyst.
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Conflicts of interest
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[Figure 1], [Figure 2], [Figure 3], [Figure 4]