Journal of Comparative Pathology最新文献

{"title":"Presumed monoclonal gammopathy and parasitized immune cells in peritoneal fluid of a dog with canine leishmaniasis","authors":"Sergio Villanueva-Saz, Diana Marteles-Aragüés","doi":"10.1016/j.jcpa.2026.10.001","DOIUrl":"10.1016/j.jcpa.2026.10.001","url":null,"abstract":"","PeriodicalId":15520,"journal":{"name":"Journal of Comparative Pathology","volume":"230 ","pages":"Pages 38-39"},"PeriodicalIF":1.2,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149182269","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hepatic lipogranulomas in canine visceral leishmaniasis: Morphological and immunohistochemical characterization using IBA-1 and MAC387","authors":"Indianara de Vargas,&nbsp;Valentina B. Marcus,&nbsp;Eduarda M.T. Santi,&nbsp;Thainã P. Vargas,&nbsp;Flavia A. Sangoi,&nbsp;Diego F. Sturza,&nbsp;Rafael A. Fighera,&nbsp;Glaucia D. Kommers,&nbsp;Mariana M. Flores","doi":"10.1016/j.jcpa.2026.09.002","DOIUrl":"10.1016/j.jcpa.2026.09.002","url":null,"abstract":"<div><div>Hepatic involvement is common in canine visceral leishmaniasis (CVL), yet uncommon inflammatory patterns remain poorly documented. This retrospective study aimed to describe the occurrence, histopathological features and immunohistochemical characterization of hepatic lipogranulomas in dogs naturally infected with <em>Leishmania</em> spp. Liver samples from 30 necropsied dogs with confirmed leishmaniasis (between 2010 and 2025) and 60 control dogs without leishmaniasis were evaluated histologically. Cases containing lipogranulomas and/or epithelioid granulomas were further assessed using periodic acid–Schiff and Prussian blue histochemical stains. Leishmaniasis cases were subjected to immunohistochemistry (IHC) for <em>Leishmania</em> spp, and those containing lipogranulomas were also subjected to IHC for IBA-1 and MAC387. Hepatic lipogranulomas, defined as aggregates of lipid-rich foamy macrophages, were identified in 5/30 (16.7%) dogs with leishmaniasis. These lesions were distributed randomly within the hepatic parenchyma and portal regions and contained intracytoplasmic pigment that was consistently PAS positive and variably Prussian blue positive. Foamy macrophages were consistently IBA-1 positive and MAC387 negative. Amastigotes were detected in all livers containing lipogranulomas and, in two cases, were observed within foamy macrophages. In an age-matched control group, lipogranulomas were identified in 2/60 dogs (3.3%) compared with 5/30 (16.7%) in the leishmaniasis group (Fisher's exact test, <em>P</em> = 0.039; odds ratio = 5.68). These findings expand the recognized histopathological spectrum of hepatic lesions observed in CVL and support the recognition of hepatic lipogranulomas as one of the inflammatory patterns that may occur in some infected dogs, while recognizing that they are not restricted to CVL.</div></div>","PeriodicalId":15520,"journal":{"name":"Journal of Comparative Pathology","volume":"230 ","pages":"Pages 32-37"},"PeriodicalIF":1.2,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149074949","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Congenital segmental absence of tracheal cartilaginous rings in two cats","authors":"Fernanda F. Perosa,&nbsp;Matheus D. Araújo,&nbsp;Matheus V. Bianchi,&nbsp;Lauren S. de Mello,&nbsp;Jean C.O. Menegatt,&nbsp;Rafael S. Monteggia,&nbsp;Saulo P. Pavarini","doi":"10.1016/j.jcpa.2026.08.001","DOIUrl":"10.1016/j.jcpa.2026.08.001","url":null,"abstract":"<div><div>Tracheal disorders are uncommon in animals. Among congenital anomalies, segmental or complete absence of tracheal rings is described rarely in humans and in animals even less frequently. This report describes the clinical, gross and histopathological features of two cases of segmental absence of tracheal rings in cats and briefly reviews tracheal disorders. Cat 1 was a 1-year-old male mixed breed (Domestic Shorthair) that presented with a history of trauma and pneumothorax, followed by persistent respiratory distress and death despite treatment. Cat 2 was a 3-year-old male stray mixed breed (Domestic Shorthair) admitted with severe dyspnoea that died before therapy could be initiated. At necropsy, both cats showed an absence of cartilaginous rings in the distal third of the trachea, approximately 2 cm cranial to the carina. The affected segments measured 1 cm (cat 1) and 2 cm (cat 2) in length, with moderate to marked narrowing of the lumina. Cat 1 also had marked emphysema in the perirenal adipose tissue. Histologically, the cartilaginous rings were completely absent and replaced by vascularized fibrous connective tissue infiltrated by a small number of mixed inflammatory cells and loss of the respiratory epithelium in the affected segments. Pulmonary lesions included alveolar emphysema, congestion, haemorrhage and oedema in cat 1, and atelectasis, congestion and alveolar oedema in cat 2. Segmental absence of tracheal rings in cats appears to occur predominantly in the distal third of the trachea. Although rare, it should be considered as a differential diagnosis in cats presenting with respiratory distress.</div></div>","PeriodicalId":15520,"journal":{"name":"Journal of Comparative Pathology","volume":"229 ","pages":"Pages 39-43"},"PeriodicalIF":1.2,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148712468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pathological aspects of an amebiasis outbreak in captive testudines","authors":"Camila I. Amaral,&nbsp;Lorena S. Bezerra,&nbsp;Daniele C. de Oliveira Freitas,&nbsp;Marina S. Sonoda,&nbsp;Marcelo P. Nogueira de Carvalho,&nbsp;Ayisa R. Oliveira,&nbsp;Maria A. Gomes,&nbsp;Roselene Ecco","doi":"10.1016/j.jcpa.2026.08.003","DOIUrl":"10.1016/j.jcpa.2026.08.003","url":null,"abstract":"<div><div>Amebiasis is a parasitic disease primarily associated with amoeboid protozoa of the genus <em>Entamoeba</em>; however, comparable infections may also be caused by other genera in different hosts. In reptiles, it is mainly attributed to <em>Entamoeba invadens</em>, which can be fatal in several species. This report describes an outbreak of amebiasis in two species of testudines, red-footed tortoises (<em>Chelonoidis carbonarius</em>) and black-bellied sliders (<em>Trachemys dorbigni</em>), from a wildlife screening and rehabilitation centre in Minas Gerais, Brazil. The facility housed around 130 testudines, and between 2022 and 2024, 79 animals died, of which 21 were diagnosed with amebiasis based on post-mortem examination. Clinical signs were non-specific, including anorexia, lethargy, reluctance to move and sudden death. Histological lesions were most frequent in the liver (17/21), duodenum (10/21) and colon (4/21), but were also present in the coelomic wall (4/21), lungs (2/21) and spleen (1/21). Lesions were characterized by necrosis, fibrin deposition and inflammatory infiltrates of lymphocytes and histiocytes, associated with numerous intralesional amoeboid protozoa. For diagnostic confirmation and species-level identification, polymerase chain reaction was performed on frozen tissues from six animals, targeting the amplification of a 109 bp fragment of the <em>E. invadens</em> 18S rRNA gene. Based on the pathological and molecular findings, along with protozoan species identification, a definitive diagnosis was established. Although amebiasis has been reported previously in reptiles, including red-footed tortoises, this is the first description in black-bellied sliders. This study highlights the importance of amebiasis as a cause of morbidity and mortality in captive testudines.</div></div>","PeriodicalId":15520,"journal":{"name":"Journal of Comparative Pathology","volume":"229 ","pages":"Pages 54-60"},"PeriodicalIF":1.2,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148828775","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Professor Stuart David Carter, BSc, PhD, FIMLS, Hon Assoc RCVS, FRCPath: born Cambridgeshire December 1952; Research Fellow Universities of Nottingham and Bristol 1979–1985, Lecturer-Reader University of Liverpool Vet School 1985–2002, Professor of Veterinary Pathology, University of Liverpool 2002–2018 (Em. Prof.: 2018–2026); died Wirral, Merseyside June 2026","authors":"","doi":"10.1016/j.jcpa.2026.07.005","DOIUrl":"10.1016/j.jcpa.2026.07.005","url":null,"abstract":"","PeriodicalId":15520,"journal":{"name":"Journal of Comparative Pathology","volume":"229 ","pages":"Page 34"},"PeriodicalIF":1.2,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148741997","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Triple amyloidosis involving fibrinogen Aα-chain, apolipoprotein A-I and EGF-containing fibulin-like matrix protein 1 in an aged dog","authors":"Susumu Iwaide,&nbsp;Mitsuhiro Ikeda,&nbsp;Ryo Tsuboi,&nbsp;Natsumi Kobayashi,&nbsp;Yoshiyuki Itoh,&nbsp;Momoko Yoshikura,&nbsp;Hirotaka Kondo,&nbsp;Tomoaki Murakami","doi":"10.1016/j.jcpa.2026.07.003","DOIUrl":"10.1016/j.jcpa.2026.07.003","url":null,"abstract":"<div><div>Amyloidosis is a group of disorders characterized by the deposition of misfolded proteins within the body, with disease subtypes classified based on the precursor protein. With the increasing longevity of captive animals, several forms of age-related amyloidosis have been reported in recent years, and attention to this disease in the welfare of aged animals has been growing. Here, we report a case of amyloidosis in a 14-year-old Shetland Sheepdog involving three age-related amyloid types. Histopathological analysis, mass spectrometry-based proteomic analysis and immunohistochemistry revealed fibrinogen Aα-chain-derived amyloid deposited in the vascular walls of the liver, glomeruli of the kidney, cardiac mitral valve, coronary artery walls and myocardial interstitium; apolipoprotein A-I-derived amyloid deposited in pulmonary vascular walls and alveolar septa; and EGF-containing fibulin-like matrix protein 1-derived amyloid deposited in the submucosa and vascular walls of the gastrointestinal tract. All three of these amyloidoses have been documented as age-related amyloidosis in animals, suggesting that ageing may also have contributed to the development of triple amyloidosis in this case. This study highlights the diversity of amyloidosis in aged dogs and emphasizes the importance of accurate organ-specific typing of amyloids.</div></div>","PeriodicalId":15520,"journal":{"name":"Journal of Comparative Pathology","volume":"229 ","pages":"Pages 14-18"},"PeriodicalIF":1.2,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148669597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Giant paraovarian cyst causing abdominal distention in a Swiss mouse (Mus musculus)","authors":"Daniel F. Barrantes Murillo,&nbsp;Luis J. Alfaro Quillas,&nbsp;Regina C. Rodrigues da Paz,&nbsp;Fernando H. Furlan Gouvêa,&nbsp;Caroline Argenta Pescador,&nbsp;Marcos de Almeida Souza","doi":"10.1016/j.jcpa.2026.07.001","DOIUrl":"10.1016/j.jcpa.2026.07.001","url":null,"abstract":"<div><div>A 9-month-old unsterilized female Swiss mouse (<em>Mus musculus</em>), housed in the Central Animal Facility of the Federal University of Mato Grosso, presented with a 1-month history of progressive abdominal distention. Occupying most of the abdominal cavity was a prominent oval-shaped, 30 g (constituting 38% of the bodyweight), 4.5 cm × 3.5 cm × 3.2 cm nodule with an irregular surface that was compressing the liver, diaphragm and thoracic cavity cranially, the right kidney laterally and the intestinal loops caudally. Histological examination confirmed a multilocular paraovarian cyst closely resembling the giant paraovarian cysts described in women. Paraovarian cysts should be suspected as a differential diagnosis in cases of marked abdominal distention in mice.</div></div>","PeriodicalId":15520,"journal":{"name":"Journal of Comparative Pathology","volume":"229 ","pages":"Pages 35-38"},"PeriodicalIF":1.2,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148712633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tympanic papillary adenoma (tympanic papilloma) in a cat - a case report","authors":"Katarzyna Paździor-Czapula,&nbsp;Mateusz Mikiewicz,&nbsp;Marcin Nowak,&nbsp;Alicja Gajosz,&nbsp;Sławomir Giziński,&nbsp;Iwona Otrocka-Domagała","doi":"10.1016/j.jcpa.2026.08.004","DOIUrl":"10.1016/j.jcpa.2026.08.004","url":null,"abstract":"<div><div>A 9-year-old cat presented with an inflammatory discharge and a polypoid mass located in the left ear canal, penetrating the tympanic membrane. The polypoid mass was removed surgically using traction-avulsion but not submitted for histological examination. Subsequently, the cat underwent computed tomography of the head, which revealed an irregular mass located in the left tympanic bulla. The mass was resected surgically during external ear canal ablation, with lateral osteotomy of the tympanic bulla, and submitted for histological examination. The tumour consisted of papillary structures lined by a single layer of cylindrical, ciliated cells with basally oriented, oval nuclei, minimal atypia, very low mitotic count and periodic acid–Schiff-positive mucin within the cytoplasm. The tumour cells immunolabelled for cytokeratins, and the Ki67 index was 10.4. Based on these findings, tympanic papillary adenoma was diagnosed. Although the clinical signs initially resolved after surgery, the tumour recurred within 17 months, as confirmed by histological examination. The recurred tumour showed an increased mitotic count and Ki67 index (18.6) compared with the primary tumour. This case report presents the clinical outcome, radiological and histological features of tympanic papillary adenoma in a cat, a very rare entity with no direct analogue in human pathology.</div></div>","PeriodicalId":15520,"journal":{"name":"Journal of Comparative Pathology","volume":"229 ","pages":"Pages 50-53"},"PeriodicalIF":1.2,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148771718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lymphoma in a cat involving the gastrointestinal tract and testes bilaterally: a diagnostic challenge in clinical practice","authors":"Masashi Yuki,&nbsp;Yuka Kobayashi","doi":"10.1016/j.jcpa.2026.06.007","DOIUrl":"10.1016/j.jcpa.2026.06.007","url":null,"abstract":"<div><div>Testicular involvement in cats with lymphoma is poorly documented, and its clinical importance remains unclear. Here, we present a case with concurrent gastrointestinal and bilateral testicular lymphoma, which was evaluated using fine-needle aspiration (FNA) cytology and polymerase chain reaction for antigen receptor rearrangements (PARR). Cytological evaluation of both lesions revealed a monomorphic population of immature lymphoid cells with features consistent with lymphoma. PARR targeting T- and B-cell receptor gene rearrangements, performed to further characterize the lesions, did not reveal monoclonal lymphoid proliferation at either site. The lack of confirmatory evidence with PARR highlights the limitations of clonality testing for FNA-based diagnosis, particularly in cases with minimally invasive sampling. The present case highlights the fact that lack of clonality does not conclusively exclude lymphoma and emphasizes the need for caution when interpreting clonality findings when diagnosis relies on minimally invasive sampling.</div></div>","PeriodicalId":15520,"journal":{"name":"Journal of Comparative Pathology","volume":"229 ","pages":"Pages 9-12"},"PeriodicalIF":1.2,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148578910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A retrospective study (2006–2020) of biopsy cases in pet guinea pigs (Cavia porcellus), degus (Octodon degus) and chinchillas (Chinchilla lanigera) at an exotic animal clinic in Tokyo, Japan","authors":"Minato Ueda,&nbsp;Takanori Shiga,&nbsp;Yasutsugu Miwa,&nbsp;Makoto Nakata,&nbsp;James K. Chambers,&nbsp;Kazuyuki Uchida,&nbsp;Nobuo Sasaki,&nbsp;Hiroyuki Nakayama","doi":"10.1016/j.jcpa.2026.07.002","DOIUrl":"10.1016/j.jcpa.2026.07.002","url":null,"abstract":"<div><div>Hystricomorphs, such as guinea pigs (<em>Cavia porcellus</em>), degus (<em>Octodon degus</em>) and chinchillas (<em>Chinchilla lanigera</em>), have become increasingly popular pet animals in Japan. However, comprehensive data on diseases in these animals remain limited, primarily restricted to single case reports, except for guinea pigs. The present study aimed to investigate the frequency of neoplastic and non-neoplastic diseases in pet guinea pigs, degus and chinchillas in Japan and to describe their epidemiological characteristics. We reviewed biopsy samples from guinea pigs (n = 134), degus (n = 57) and chinchillas (n = 16) collected at the Miwa Exotic Animal Hospital and the Laboratory of Veterinary Pathology, University of Tokyo, between 2006 and 2020. The most common condition in guinea pigs was integumentary disorders (n = 83; 61.9%), with mammary carcinoma (n = 41; 49.1%) being the most prevalent. The second most common condition was female reproductive disorders (n = 43; 32.1%), with ovarian cysts (n = 11; 25.6%) the most frequent. In degu samples integumentary disorders (n = 23; 40.3%) were the most common, followed by respiratory disorders (n = 22; 38.5%). Soft tissue sarcoma (n = 15; 65.2%) was the most frequently observed integumentary disorder, while fibroma with bone formation (n = 10; 45.4%) was the most prevalent respiratory disorder. In chinchilla samples female reproductive disorders (n = 13; 81.2%) were the most common, with endometritis being the most frequent (n = 5; 38.4%). The frequency of disorders peaked at 3–4 years old in guinea pigs and degus. No age-specific peaks were observed in chinchillas. This is the largest retrospective histopathological study on degus and chinchillas to date and the findings provide valuable insights for veterinarians treating hystricomorphs.</div></div>","PeriodicalId":15520,"journal":{"name":"Journal of Comparative Pathology","volume":"229 ","pages":"Pages 19-26"},"PeriodicalIF":1.2,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148678971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}