Department of Small Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, 77843, USA.
Department for Small Animals, Veterinary Teaching Hospital, College of Veterinary Medicine, University of Leipzig, An den Tierkliniken 23, DE-04103, Leipzig, SN, Germany.
BMC Vet Res. 2021 May 13;17(1):192. doi: 10.1186/s12917-021-02896-9.
Histoplasma (H.) capsulatum is a dimorphic fungus, and infection is typically via inhalation of microconidia. After conversion to the yeast phase within the lung, the organism is subsequently disseminated to other tissues by macrophages. Nasal histoplasmosis appears to be a rare condition in dogs.
We report the clinical case of a 4.5-year-old male neutered Cocker spaniel/Poodle mix, 7.7 kg, body condition score 6/9, that presented with a 3-month history of sneezing and left-sided mucoid nasal discharge. The history also included a mild swelling (transient) of the right carpus with a lameness (grade II-III/IV), coinciding with the onset of sneezing and nasal discharge. The dog lived primarily indoors in the Texas Gulf Coast area. On physical examination, the dog was febrile, and the left nostril was swollen, ulcerative, deformed, and hypopigmented. Mandibular lymph nodes were firm and mildly enlarged bilaterally. Mild lymphopenia, thrombocytopenia, and hyperglobulinemia were noted. Thoracic radiographs were unremarkable. Computed tomography and rhinoscopy revealed swelling of the rostral portion of the left and right nasal passages. Cytology and histology of biopsies of the affected nasal tissue showed pyogranulomatous inflammation and yeast organisms consistent with H. capsulatum. Weak antigenuria was detected on the MVista H. capsulatum antigen test. Treatment with oral itraconazole led to a resolution of the nasal signs and normalization of the appearance of the nostril over 13 weeks, and neither antigenuria nor antigenemia was detected on several recheck examinations. The dog remained in good general and physical condition and showed no signs of disease recurrence more than 6 years after the last examination.
We report a rare case of nasal mucocutaneous histoplasmosis in an immunocompetent dog, with an excellent clinical response to oral itraconazole. This case documents that histoplasmosis in dogs can affect primarily the nasal cavity, which responds rapidly to triazole antifungal therapy and has a good prognosis. A similar case has only been reported in human medicine in a young adult.
荚膜组织胞浆菌（H.）是一种双相真菌，感染通常通过吸入微孢子而发生。在肺部转化为酵母相后，该生物体随后通过巨噬细胞传播到其他组织。鼻组织胞浆菌病似乎在狗中是一种罕见的疾病。
我们报告了一例 4.5 岁雄性已绝育可卡犬/贵宾犬混血犬的临床病例，体重 7.7 公斤，体况评分为 6/9，病史为 3 个月的打喷嚏和左侧粘脓性鼻分泌物。该病史还包括右腕部轻度肿胀（短暂）和跛行（II-III/IV 级），与打喷嚏和鼻分泌物同时发生。该犬主要在德克萨斯海湾地区的室内生活。体格检查时，该犬发热，左鼻孔肿胀、溃疡、变形和色素减退。下颌淋巴结双侧质地坚硬且轻度肿大。轻度淋巴细胞减少症、血小板减少症和球蛋白血症。胸部 X 射线未见异常。计算机断层扫描和鼻镜检查显示左右鼻腔的前段肿胀。受影响的鼻组织活检的细胞学和组织学检查显示化脓性肉芽肿性炎症和与荚膜组织胞浆菌一致的酵母生物体。MVista 荚膜组织胞浆菌抗原检测发现弱阳性尿抗原。口服伊曲康唑治疗导致 13 周内鼻症状消退，鼻孔外观恢复正常，多次复查均未检测到尿抗原和血抗原。该犬整体状况良好，在最后一次检查后 6 年以上未出现疾病复发迹象。
我们报告了一例免疫功能正常犬罕见的鼻粘膜炎性组织胞浆菌病病例，口服伊曲康唑治疗具有极好的临床反应。该病例表明，犬的组织胞浆菌病可主要影响鼻腔，对三唑类抗真菌治疗反应迅速，预后良好。在人类医学中仅报道过一例类似的病例，发生于一名年轻成年人。
