Infiltrative spinal lipoma in a Canada goose (Branta canadensis).
Key words: infiltrative spinal lipoma, paraparesis, adipocytes, lipid, cord, avian, Canada goose, Branta canadensis
A 3.4-kg adult Canada goose (Branta canadensis) was presented to the Wildlife Medical Clinic at the University of Illinois (Urbana, IL,
USA) after a member of the public found the goose lying on the ground, unable to walk. Initial assessment of the bird revealed that it was alert and responsive and in good body condition based on pectoral muscle mass and subcutaneous body fat stores. The goose was able to move its legs but was unable to stand or ambulate when prompted. Wing function appeared unaffected bilaterally. The working diagnosis was paraparesis secondary to spinal trauma or toxicosis. There were no external signs of trauma.
Initial treatment consisted of fluid administration (35 mL/kg SC q12h, 0.9% sodium chloride), as well as meloxicam (0.5 mg/kg PO q12h, Metacam, Boehringer Ingelheim Vetmedica, St. Joseph, MO, USA) for anti-inflammatory effect and butorphanol (2 mg/kg IM initially, followed by 1 mg/kg IM q12h, Torbugesic, Zoetis, Florham Park, NJ, USA) for analgesia.
A neurologic assessment revealed intact cranial nerves and normal spinal reflexes in the wings and pelvic limbs, with absent conscious proprioception and decreased motor function in both legs. Fullbody radiographic evaluation with ventrodorsal and lateral projections demonstrated a single 5mm-diameter round metal object in the left caudal coelom consistent with gunshot (Fig 1). No other abnormalities were observed. Because the metal was not associated with any gastrointestinal structures or fractured bone, serum lead levels were not evaluated. Results of hematologic testing and plasma biochemical analysis were unremarkable compared with in-house reference intervals.
The goose continued to receive subcutaneous fluids and meloxicam twice daily as previously described. The pain management protocol was changed after 3 days from injectable butorphanol to oral tramadol (30 mg/kg q12h), and supervised swimming in a shallow pool was initiated in an effort to strengthen the goose's legs. Despite treatment, there were no signs of improvement in neurologic function, and 1 week after admission, the goose was euthanatized and submitted for postmortem examination at the University of Illinois Veterinary Diagnostic Laboratory.
[FIGURE 1 OMITTED]
Postmortem evaluation was conducted immediately after the euthanasia. The foreign metal sphere noted on radiographs was confirmed in the left abdominal air sac. The sphere was rusty and encased by a thin layer of fibrous tissue within the membrane of the air sac. The spine was sectioned sagittally after formalin fixation such that the vertebral canal and spinal cord could be examined. A 1-cm long segment of lumbosacral spinal cord was infiltrated by an intradural growth located on the dorsal aspect of the spinal cord (Fig 2A). Dorsally, the growth was confined by the dura mater, but it compressed and caused a dome-shaped dorsal protrusion of the vertebral arch, presumably from the pressure of the growth in such a restricted space of spinal canal. The growth itself was white to tan, soft yet solid. Histopathologic examination indicated that the growth was nonencapsulated and infiltrated a segment of the spinal cord (Fig 2B). The growth comprised lobules of well-differentiated, mature adipocytes (Fig 2C). The adipocytes were almost entirely of lipid with barely discernible nuclei. There was mild anisocytosis and mild anisokaryosis. No mitotic figures were noted. Other viscera were grossly and histologically unremarkable. The final diagnosis was paraparesis as a result of an intradural, infiltrative spinal lipoma with segmental infiltration of the lumbosacral spinal cord and dorsal compression of the vertebral arch.
[FIGURE 2 OMITTED]
This clinical report describes a case of paraparesis secondary to an infiltrative spinal lipoma in a free-living Canada goose. Lipomas are defined as well-circumscribed benign tumors composed of mature, well-differentiated adipocytes. (1,2) As their name implies, infiltrative lipomas are more locally invasive than lipomas. (3) Despite the difference in behavior of these 2 tumors, they are identical in cytologic appearance, and the only way to definitively differentiate a lipoma from an infiltrative lipoma is with histopathologic examination. (1,3-5)
Infiltrative lipomas have been described in a variety of anatomic locations in dogs, cats, cows, horses, sheep, snakes, a blue-crowned conure (Aratinga acuticaudata), and a Mediterranean seabass (Dicentrarchus labrax (1-4,6-15)) Generally, infiltrative lipomas are uncommon, but they are especially rare within the spinal canal. (2,7) When these tumors are present within the spinal canal and affect the related segment of spinal cord, the history and physical examination findings are very consistent between ambulatory species. Animals present with an abnormal gait or lameness, hyperor hyporefiexia in the affected limb or limbs, and conscious proprioception deficits. (1,2,4,6) After these clinical findings are observed, one or more imaging modalities may be used to further localize a lesion.
Survey radiographs are readily accessible to most clinicians and may provide important insight to the cause of neurologic dysfunction, especially in cases of trauma or orthopedic disease. Myelography may be used to identify more accurately subtle changes within the spinal canal, although myelograms are more inherently challenging in avian species because of a narrow cerebromedullary cistern and the lack of contrast flow to the caudal regions of the spinal canal. (16) Alternatively, computed tomography (CT) and magnetic resonance imaging (MRI) are less technically challenging and can provide more accurate visualization of spinal structures. CT allows excellent evaluation of calcified structures, whereas MRI is ideal to assess soft tissues, and both modalities create multiplanar imaging to remove superimposition. (16-18) Several clinical reports have noted the advanced diagnostic capabilities of CT, MRI, or both over radiography; however, CT and MRI are more expensive and less accessible in many cases and are thus utilized less often than radiography alone. (19-21)
Successful treatment has been reported with local excision, including laminectomy of the affected vertebral segment; additional radiation therapy is reported to be unnecessary. (1-4,6) Until recently, neoplasia of any kind has been rarely reported in free-living wildlife. A survey of 43 facilities in the United States in 2000 indicated that trauma, shock, and starvation were the most common findings in the more than 140,000 wildlife patients admitted over a 3-year period; tumors were categorized as "other" and the relative frequency ranged from none to low. (22) Yet neoplasia has been documented in wildlife for decades. As early as 1950, neoplastic tumors were noted in wild animals, and new cases of neoplasia continue to emerge. (23) Both benign and malignant tumors have been diagnosed in free-living game birds, passerine birds, raptors, and waterbirds, among others. (24-41) In Canada geese in particular, neurofibrosarcoma, lipoma, liposarcoma, fibroma, and spindle cell sarcoma have all been reported. (27,32,34,39,41) The documented lipid-based tumors originated in skeletal muscle. (32,34)
Disease surveillance in wildlife has always been limited by the free-living nature of these animals. Most wild animals that succumb to disease are never encountered, and the ones that are found are rarely definitively diagnosed. The efforts required to identify and confirm neoplastic processes often include MRI or CT or histopathology, none of which is available to most wildlife caretakers. Despite these hurdles, it is imperative that we strive to identify and document the prevalence of neoplasia in wildlife. Determining the etiology and behavior of these cancers is crucial to prevention for the individuals and species affected, as well as to contribute to our understanding of cancer as a whole and its effects on conservation efforts. (42) Furthermore, trends in wildlife neoplastic pathology may ultimately provide insight into potential threats to human health given the correlation between high levels of environmental contaminants and reported wildlife cancer. (42-45) This clinical report describes a previously undocumented cause of paraparesis in a bird, and to our knowledge, this is the first report of an infiltrative spinal lipoma in a bird.
Nichole Rosenhagen, DVM, Julia K. Whittington, DVM, and Shih-Hsaun Hsiao, DVM, PhD
From the Department of Veterinary Clinical Medicine. University of Illinois, 1008 W Hazelwood Drive, Urbana, IL 61802, USA (Rosenhagen, Whittington); and the Veterinary Diagnostic Laboratory, College of Veterinary Medicine, University of Illinois, 2001 S Lincoln Avenue. Urbana. IL 61802, USA (Hsiao).
(1.) Morgan LW. Toai R, Siemering G, Gavin P. Imaging diagnosis--infiltrative lipoma causing spinal cord compression in a dog. Vet Radiol Ultrasound. 2007;48(1):35-37.
(2.) O'Driscoll JL. McDonnell JJ. What is your neurologic diagnosis? Infiltrative lipoma of the thoracic spinal cord. J Am Vet Med Assoc. 2006;229(6):933-935.
(3.) McEntee MC, Thrall DE. Computed tomographic imaging of infiltrative lipoma in 22 dogs. Vet Radiol Ultrasound. 2001; 42(3):221-225.
(4.) Hobert MK, Brauer C, Dziallas P, et al. Infiltrative lipoma compressing the spinal cord in 2 large-breed dogs. Can Vet J. 2013;54(1):74-78.
(5.) Pease A. Lipoma and infiltrative lipoma: a diagnostic dilemma. Equine Vet Educ. 2010;22(12):608-609.
(6.) Agut A, Anson A, Navarro A, et al. Imaging diagnosis--infiltrative lipoma causing spinal cord and lumbar nerve root compression in a dog. Vet Radiol Ultrasound. 2013;54(4):381-383.
(7.) Miller JA, Urie BK, Green EM. What is your diagnosis? Infiltrative lipomas. J Am Vet Med Assoc. 2014;245(1):43-44.
(8.) Giancamillo MD, Lombardo R, Beretta S, et al. Congenital facial infiltrative lipoma in a calf. Vet Radiol Ultrasound. 2002;43(1):46-49.
(9.) Baker D, Kreeger J. Infiltrative lipoma in the heart of a horse. Cornell Vet. 1987;77(3):258-262.
(10.) Erkert RS, Moll HD, Macallister CG, et al. Infiltrative lipoma in an American quarter horse gelding. Equine Vet Educ. 2007;19(7):380-383.
(11.) Shahrzad A, Kheirandish R, Namjoo AR. Occurrence of infiltrative lipoma with remarkable abomasal ulcers in a lamb--a case report. Vet Arh. 2011 ;81 (5):683-690.
(12.) Burkert BA, Tully TN, Nevarez J. et al. Infiltrative lipoma in a corn snake (Elaphe guttata guttata). J Herpetol Med Surg. 2002;12:33-35.
(13.) Haag MK, Hernandez-Divers SM, Latimer KS. Infiltrative lipoma in a black rat snake, Elaphe obsoleta. J Herpetol Med Surg. 2008; 17(4): 129-131.
(14.) Mehler SJ, Briscoe J A, Hendrick MJ, Rosenthal KL. Infiltrative lipoma in a blue-crowned conure (Aratinga acuticaudata). J Avian Med Surg. 2007;21(2): 146-149.
(15.) Marino F, Chiofalo B, Mazzullo G, Panebianco A. Multicentric infiltrative lipoma in a farmed Mediterranean seabass Dicentrarchus labraw a pathological and biochemical case study. Dis Aquat Organ. 2011;96(3):259-264.
(16.) Clippinger TL, Bennett RA, Piatt SR. The avian neurologic examination and ancillary neurodiagnostic techniques: a review update. Vet Clin North Am Exot Anim Pract. 2007;10(3):803-836.
(17.) Thomson CE, Kornegay JN, Burn RA, et al. Magnetic resonance imaging--a general overview of principles and examples in veterinary neurodiagnosis. Vet Radiol Ultrasound. 1993;34(1):2-17.
(18.) Romagnano A, Shiroma JT, Heard DJ. Magnetic resonance imaging of the brain and coelomic cavity of the domestic pigeon (Columba livia domestica). Vet Radiol Ultrasound. 1996;37(6):431-440.
(19.) Emerson CL, Eurell JC, Brown MD, et al. Ruptured intervertebral disc in a juvenile king penguin (Aptenodytes patagoniea). J Zoo Wildl Med. 1990;21 (3):345-360.
(20.) Stauber E, Holmes S, DeGhetto DL. Finch N. Magnetic resonance imaging is superior to radiography in evaluating spinal cord trauma in three bald eagles (Haliaeetus leucocephalus). J Avian Med Surg. 2007;21(3): 196-200.
(21.) Bradford C, Bronson E, Kintner L, et al. Diagnosis and attempted surgical repair of hemivertebrae in an African penguin (Spheniscus demersus). J Avian Med Surg. 2008;22(4):331-335.
(22.) Casey AM III, Casey SJ. A survey of conditions seen in wildlife admitted for wildlife rehabilitation. Wildl Rehabil. 2000;18:143-160.
(23.) Lopushinsky T, Fay LD. Some benign and malignant neoplasms of Michigan cottontail rabbits. J Wildl Dis. 1967;3(4): 148 151.
(24.) Howerth EW, Schorr LF, Nettles VF. Neoplasia in free-flying ruffed grouse (Bonasa umbellus). Avian Dis. 1986;30(1):238-240.
(25.) Manarolla G, Radaelli E, Pisoni G, et al. Rhabdomyosarcoma of the pectoral muscles of a free-living European robin (Erithacus rubecula). Avian Pathol. 2008;37(3):311-314.
(26.) Harris MC, Sleeman JM. Morbidity and mortality of bald eagles (Haliaeetus leucocephalus) and peregrine falcons (Falco peregrinus) admitted to the Wildlife Center of Virginia, 1993-2003. J Zoo Wildl Med. 2007;38(1):62-66.
(27.) Siegfried LM. Neoplasms identified in free-flying birds. Avian Dis. 1983;27(l):86-99.
(28.) Bates G, Tucker RL, Ford S, Mattix ME. Thyroid adenocarcinoma in a bald eagle (Haliaeetus leucocephalus). J Zoo Wildl Med. 1999;30(3):439-442.
(29.) Morishita TY, Fullerton AT, Lowenstine LJ, et al. Morbidity and mortality in free-living raptorial birds of northern California: a retrospective study, 1983-1994. J Avian Med Surg. 1998;12(2):78-81.
(30.) Jaensch SM, Butler R, O'Hara A, et al. Atypical multiple, papilliform, xanthomatous, cutaneous neoplasia in a goose (Anser anser). Aust Vet J. 2002;80(5):277-280.
(31.) Reid HAC, Herron AJ, Hines ME, et al. Metastatic malignant melanoma in a Mandarin duck (Aix galericulata). Avian Dis. 1993;37(4):1158-1162.
(32.) Daoust PY, Wobeser G, Rainnie DJ, Leighton FA. Multicentric intramuscular lipomatosis/fibromatosis in free-flying white-fronted and Canada geese. J Wildl Dis. 1991 ;27(1): 135-139.
(33.) Hatai H, Ochiai K, Nakamura S, et al. Hepatic myelolipoma and amyloidosis with osseous metaplasia in a swan goose (Anser cvgnoides). J Comp Pathol. 2009; 141 (4):260-264.
(34.) Doster AR, Johnson JL. Duhamel GE, et al. Liposarcoma in a Canada goose (Branta canadensis). Avian Dis. 1987;31(4):918-920.
(35.) Dillberger JE, Citino SB, Altman NH. Four cases of neoplasia in captive wild birds. Avian Dis. 1987;31(1):206-213.
(36.) Mawdesley-Thomas LE, Solden DH. Osteogenic sarcoma in a domestic white goose (Anser anser). Avian Dis. 1967;11(3):365-370.
(37.) Uetsuka K, Suzuki T, Doi K, Nunoya T. Malignant Sertoli cell tumor in a goose (Anser cygnoides domesticus). Avian Dis. 2012;56(4):781-785'
(38.) Bradford C, Wack A, Trembley S, et al. Two cases of neoplasia of basal cell origin affecting the axillary region in anseriform species. J Avian Med Surg. 2009;23(3):214-221.
(39.) Locke LN. Multicentric neurofibrosarcoma in a Canada goose. Avian Dis. 1963;7(2): 196-202.
(40.) Leach S, Heatley JJ, Pool RR, Spaulding K. Bilateral testicular germ cell-sex cord-stromal tumor in a Pekin duck (Anas platyrhynchos domesticus). J Avian Med Surg. 2008;22(4):315-319.
(41.) Gates RJ, Woolf A, Caithamer DF, Moritz WE. Prevalence of spindle cell sarcomas among wild Canada geese from southern Illinois. J Wildl Dis. 1992;28(4):666-668.
(42.) McAloose D, Newton AL. Wildlife cancer: a conservation perspective. Nat Rev Cancer. 2009;9(7):517-526.
(43.) De Guise S, Lagace A, Beland P. Tumors in St. Lawrence beluga whales (Delphinapterus leucas). Vet Pathol. 1994;31(4):444-449.
(44.) Gulland FM, Trupkiewicz JG, Spraker TR, Lowenstine LJ. Metastatic carcinoma of probable transitional cell origin in 66 free-living California sea lions (Zalophus californianus), 1979 to 1994. J Wildl Dis. 1996;32(2):250-258.
(45.) Ylitalo GM, Stein JE, Horn T, et al. The role of organochlorines in cancer-associated mortality in California sea lions (Zalophus calif ornianus). Mar Pollut Bull. 2005;50(1):30-39.
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|Title Annotation:||Clinical Report|
|Author:||Rosenhagen, Nichole; Whittington, Julia K.; Hsiao, Shih-Hsaun|
|Publication:||Journal of Avian Medicine and Surgery|
|Article Type:||Clinical report|
|Date:||Mar 1, 2016|
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