Proliferative Lesions of the Endometrium of 50 Four-Toed Hedgehogs ( Atelerix albiventris)

Mammary and reproductive tract tumours and tumour-like lesions of 286 small pet mammals: a retrospective study

Small mammals are very popular companion animals, and the incidence of particular tumour types in these animals is the subject of extensive research. We carried out a retrospective and comparative analysis of the incidence of reproductive tract and mammary tumours and tumour-like lesions collected from 103 pet rabbits, 75 pet rats, 71 guinea pigs, 12 mice, 11 hamsters, eight African pygmy hedgehogs, four ferrets and two chinchillas. The results indicate that uterine tumours and tumour-like lesions are common in pet rabbits, guinea pigs and African pygmy hedgehogs. In pet rabbits, the most common uterine tumour was endometrial adenocarcinoma, while in guinea pigs benign lesions predominated (ie, leiomyoma, endometrial adenoma, cystic endometrial hyperplasia and deciduoma). Uterine tumours in African pygmy hedgehogs included adenosarcomas and endometrial polyps. Ovarian lesions were found only in guinea pigs (ovarian rete adenomas, rete cysts) and African pygmy hedgehogs (mostly granulosa cell tumours), while testicular tumours were diagnosed in pet rabbits, one pet rat and one guinea pig. Mammary tumours were common in pet rabbits, pet rats, guinea pigs, mice, hamsters and African pygmy hedgehogs. In pet rats, the most common mammary tumour was fibroadenoma, while in other animals carcinomas predominated. In guinea pigs and, to a lesser extent, in pet rats, a significant percentage of mammary tumours occurred in males. Guinea pigs seem to be predisposed to mammary tumours of ductal origin. This study describes for the first time uterine angioleiomyoma in the pet rabbit and mammary spindle cell carcinoma in the Djungarian hamster and chinchilla.

Myxofibrosarcoma of the penis in an African pygmy hedgehog (Atelerix albiventris) - A clinical case

A 3-year-old, 420 g, intact male African pygmy hedgehog (Atelerix albiventris) was presented with a sudden appearance of a mass protruding from its preputium. A detailed physical examination revealed the presence of a polyp-like mass, connected to the mucous membrane of the penis and a second, multilobular mass with a larger base. Both masses were surgically removed. While the histopathological examination of the polyp-like mass revealed only a chronic active inflammatory reaction, the histopathological examination of the multilobular mass revealed a tumorous tissue composed of spindle-shaped cells, irregularly oval or polygonal in some places. Focal tumour cells with a myxoid differentiation were observed in the greater part of this tumour. The stroma was made up of sparse fibrous tissue. The surface epithelium was hyperplastic with ulcerations and necrosis. The tumour was classified as a myxofibrosarcoma. Two weeks post-surgery, the patient did not show any clinical signs of the presented disease. According to our knowledge, this is the first published case of the surgical treatment of penile myxofibrosarcoma in an African pygmy hedgehog.

Highly malignant endometrial stromal sarcoma in a cat

An 11-year-old female Persian cat underwent ovariohysterectomy due to dilation of the uterine cavity with irregular thickening of the wall. Macroscopically, the middle and distal regions of the left uterine horn were swollen and the uterine wall was irregularly thickened due to the development of multiple coalescent, variably sized nodules. Microscopically, the nodules had originated in the endometrium and were composed of round to polygonal neoplastic cells arranged in dense sheets or ill-defined fascicles. The neoplastic cells had locally invaded the myometrium and reached the subserosa, with lymphovascular invasion. Immunohistochemically, the neoplastic cell population was partially positive for CD10, an established marker of endometrial stromal sarcoma (ESS) in humans, with focal and diffuse nuclear immunopositivity for oestrogen and progesterone receptors and immunonegativity for desmin and α-smooth muscle actin. Based on these findings, the uterine tumour was diagnosed as ESS and was considered to correspond morphologically to high-grade ESS in humans.

Adenomyomatous uterine polyp in a Miniature Pinscher: histologic, immunohistochemical, and clinical aspects

A 14-y-old Miniature Pinscher bitch was admitted to a veterinary clinic because of inappetence and a distended abdomen; ultrasound examination revealed a fluid-filled uterus with a single 1-cm hyperechoic nodule in its lumen. Ovariohysterectomy was performed. Grossly, the uterine horns were distended irregularly and asymmetrically, and the uterine lumen contained 200-300 mL of brown watery fluid. A single white polypoid 0.9-cm diameter nodule was present at the site of the distended uterine horn and arose from the endometrium with a narrow stalk. Histologically, the polyp consisted of dense, smooth muscle fascicles admixed with glandular components; its surface was covered by simple cuboidal epithelium with areas of squamous metaplasia. The myomatous cells expressed the myogenic markers smooth muscle actin and desmin. We interpreted the mass as an adenomyomatous uterine polyp, which is a rare variant of an endometrial polyp.

Granulosa cell tumor in 8 African pygmy hedgehogs (Atelerix albiventris)

A retrospective study involving eight African pygmy hedgehogs histopathologically diagnosed with granulosa cell tumors was conducted. The age at onset was 2.2–4.5 years, with a median age of 3.6 years. The most common clinical signs were hematuria and abdominal distension, which were observed in >50% cases. Exploratory laparotomy was performed in all cases, and ovariohysterectomy or excision of the abdominal mass was performed. Patients with only hematuria survived for >250 days after surgery, whereas those with initial ascites showed recurrence of ascites or tumor growth and survived for approximately 130 days after surgery. Intraperitoneal injection of carboplatin was performed in three recurrent cases. In one of these three cases, the tumor mass disappeared. Hence, carboplatin can be considered a potential antineoplastic drug for the treatment of granulosa cell tumors.

Eosinophilic Leukaemia and Systemic Mycobacterium marinum Infection in an African Pygmy Hedgehog (Atelerix albiventris)

A two-year-old male African pygmy hedgehog (Atelerix albiventris) presented with lethargy and anorexia. Ultrasonographic and radiographic examinations revealed splenomegaly and pneumonia, respectively. Prominent leucocytosis, consisting mainly of large atypical eosinophils, was observed in a peripheral blood smear. Necropsy revealed a black scab on the left hindlimb, which was swollen, an enlarged left inguinal lymph node, firm oedematous lungs, splenomegaly and multiple nodules in the lung, spleen and liver. Histopathologically, infiltration of numerous eosinophils was seen in lung, spleen, liver, kidney, lymph node and adrenal medulla tissues. Necrotizing granulomatous lesions, with intralesional acid-fast bacilli, were found in the lung, spleen, liver, left inguinal lymph node and left hindlimb. Mycobacterium marinum was identified by broad-range polymerase chain reaction targeting of the bacterial 16S rRNA gene. To the best of our knowledge, this is only the second reported case of systemic M. marinum infection in any mammalian species.

Histological and Immunohistochemical Features of Normal Histiocytes and Langerhans Cells, and Histiocytic Sarcomas in Four-Toed Hedgehogs (Atelerix albiventris)

Histiocytic sarcoma (HS) is a haematopoietic tumour of histiocyte origin that has been sporadically reported in four-toed hedgehogs (Atelerix albiventris). The present study aimed to investigate clinical, gross, histopathological and immunohistochemical features of HS in eight hedgehogs. Histological and immunohistochemical features of normal histiocytes and Langerhans cells (LCs) of hedgehogs were also investigated. HLA-DR-, Iba-1- and E-cadherin-positive LCs were observed in the epidermis, while Iba-1- and CD204-positive histiocytes were detected in the lymph nodes and spleen of normal hedgehogs. Localized HS (six cases) developed in the skin and spleen, while disseminated HS (two cases) occurred in the intestine. Tumour cells of disseminated HS were also distributed within the mesenteric lymph nodes, liver, kidney, spleen, lung and adrenal glands. Tumour cells of both localized and disseminated HS were composed of histiocytic cells, spindle to pleomorphic cells, multinucleated giant cells and erythrophagocytic cells. Most tumour cells were immunopositive for Iba-1, CD204 and lysozyme. A small number of tumour cells were positive for E-cadherin and CD208, and the tumour cells in one case were positive for HLA-DR. These results suggest that the tumour cells have variable features of histiocyte origin, including dendritic cells, LCs and macrophages. The behaviour of HS in the hedgehog was very aggressive, and 50% of cases died within 90 days of resection. The present study also highlighted the tendency for local tumour recurrence in localized cutaneous HS cases, suggesting a requirement for a long-term follow-up after excision.

Geriatric Hedgehogs

African hedgehogs are susceptible to aging changes like those of other small exotic mammals. Common conditions of the geriatric hedgehog include heart disease, chronic renal disease, and dental/periodontal disease. Hedgehogs are unique in that they have an unusually short life span and a propensity for neoplasia. These 2 factors make it especially common for exotic animal practitioners to encounter geriatric hedgehogs affected by one of the many conditions outlined in this article.

Immunohistochemical Studies of αSMA in the Epididymis of African Four-Toed Hedgehog (Atelerix albiventris)

The epididymis plays an important role in sperm maturation, storage, transport and in the secretion of enzymes and proteins into the tubular lumen. In this study, we examined the histology, microstereology and immunohistochemical localization of alpha smooth muscle (αSMA) in the three regions of the epididymis of the African four-toed hedgehog (Atelerix albiventris). Ten adult males were captured from the wild in Ibadan, Nigeria, between May and October, 2016. The animals were euthanized and the epididymis (caput, corpus and cauda regions) were retrieved and fixed in buffered neutral formalin ahead of the paraffin technique, following standard procedures. The duct of the epididymis was lined by pseudostratified columnar epithelium comprising basal, principal and apical cells as well as intraepithelial lymphocytes in proximity to basal cells. The principal cells, the major cells encountered within the epididymal epithelium of the animal, decreased in population from the caput to the cauda epididymidis while the apical cells were more abundant in the cauda epididymidis. Positive reactions to αSMA were observed in the peritubular muscular coat of the epididymal duct as well as blood vessels across the three regions of the epididymis with the caput and cauda epididymidis showing stronger positive reactions compared to the corpus epididymidis. This study demonstrated that the histology, microstereology as well as the cellular constituents of the epididymal duct of the Atelerix albiventris are similar to those of other mammals with a slight variation. It has also highlighted variation in the localization of αSMA across the regions of the epididymis of the animal.

Endometrial polyp with chronic endometritis in an African pygmy hedgehog (Atalerix albiventris) – a case report

An African pygmy hedgehog (Atalerix albiventris) (APH) was admitted to the clinic with a history of vaginal bleeding. Examination showed poor clinical status of the patient based on haemogram values. The ultrasound showed an enlarged uterus filled with an anechoic content without the presence of free abdominal fluid. Ovariohysterectomy was performed under general inhalation anaesthesia. Histopathology examination was performed on tissue samples of the uterus with the final diagnosis of an endometrial polyp with endometrial cystic hyperplasia and chronic endometritis. In regard to the diagnostic findings, therapeutic option and postoperative care performed in this case, it is important to emphasize the fact that an early diagnosis of a reproductive disease contributes to proper treatment and a positive outcome. The endometrial polyp with cystic endometrial hyperplasia and chronic endometritis should be added to the list of differential diagnoses in cases where neoplasia of the reproductive system is suspected in an APH.

A retrospective study of disease incidence in African pygmy hedgehogs (Atelerix albiventris)

The African pygmy hedgehog (Atelerix albiventris) is becoming a popular pet in Japan. The aim of this study was to determine the incidence of various diseases in African pygmy hedgehogs. We histologically investigated 105 samples from 100 privately-owned pet African pygmy hedgehogs that were submitted to two laboratories (North Lab and Patho Labo) between 2012 and 2017. Tissues submitted for this study were taken from female reproductive organs (33 cases; 31.43%), skin (20 cases; 19.05%), and the oral mucosa (19 cases; 18.1%). The most common histological diagnoses included endometrial stromal nodules identified as benign uterine neoplasia (14 cases; 13.33%); endometrial polyps identified as non-neoplastic polyps (7 cases; 6.67%), gingival hyperplasia and chronic suppurative inflammation in the oral mucosa (11 cases; 10.48%), fibrosarcomas in the skin (8 cases; 7.62%), and mammary tumors (8 cases; 7.62%). In this study, lymphoma and oral squamous cell carcinoma were less common than in the previous reports. The present study revealed the disease prevalence in captive African pygmy hedghogs that were histopathologically examined.