Wheelwright Matthew, Yousaf Hira, Plummer Regina, Cartwright David, Gaertner Wolfgang, Amin Khalid
Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, USA.
Division of Colon and Rectal Surgery, Department of Surgery, University of Minnesota, Minneapolis, MN, USA.
Am J Case Rep. 2019 Nov 25;20:1740-1744. doi: 10.12659/AJCR.918220.
BACKGROUND Disseminated histoplasmosis, a disease that can present years after exposure to the causative organism, may manifest in many diverse ways. Although the gastrointestinal tract is involved in most cases, the initial presentation occurring along the gastrointestinal tract, including the colon and rectum, is infrequent. CASE REPORT This case report describes a 66-year-old male patient who presented with an indurated painful perianal lesion that appeared highly suspicious for malignancy on imaging. The patient had no known history of well-established immunocompromised state except for a short course of prednisolone for chronic obstructive pulmonary disease management. A biopsy of the mass was performed, showing chronic inflammation with clusters of epithelioid histiocytes containing characteristic, PAS-fungus stain-positive, intracellular yeast forms consistent with histoplasmosis. There was no evidence of malignancy. A subsequent work-up revealed perihilar nodularity on chest X-ray suggestive of calcified granuloma, a positive Histoplasma Capsulatum Antigen test result, and mildly decreased CD4: CD8 ratio of unknown significance. HIV testing was negative. Treatment with itraconazole and terbinafine was initiated, and at 5-months follow-up, the patient reported significant improvement in signs and symptoms, with undetectable Histoplasma antigen on repeat testing. CONCLUSIONS This case represents an extremely rare presentation of histoplasmosis infection, and highlights the fact that presenting symptoms of histoplasmosis can be vague and may mimic other disease processes, including neoplasia. Biopsy of the lesion with PAS staining and serologic testing is critical in establishing the correct diagnosis.
背景 播散性组织胞浆菌病是一种在接触致病病原体数年之后才会出现的疾病，其表现形式多种多样。虽然在大多数病例中胃肠道会受累，但最初沿胃肠道（包括结肠和直肠）出现的症状并不常见。病例报告 本病例报告描述了一名66岁男性患者，其肛周出现硬结性疼痛病变，影像学检查高度怀疑为恶性肿瘤。除了因慢性阻塞性肺疾病接受过短期泼尼松龙治疗外，该患者无已知的明确免疫功能低下病史。对肿块进行了活检，结果显示为慢性炎症，伴有成群的上皮样组织细胞，其中含有符合组织胞浆菌病特征的、过碘酸雪夫染色（PAS）真菌染色阳性的细胞内酵母形式。没有恶性肿瘤的证据。随后的检查显示胸部X线提示肺门周围有结节，提示钙化性肉芽肿，荚膜组织胞浆菌抗原检测结果为阳性，CD4:CD8比值轻度降低，意义不明。HIV检测为阴性。开始使用伊曲康唑和特比萘芬进行治疗，在5个月的随访中，患者报告症状和体征有明显改善，重复检测时组织胞浆菌抗原检测不到。结论 本病例代表了组织胞浆菌病感染极为罕见的表现形式，并突出了组织胞浆菌病的症状可能模糊不清且可能模仿其他疾病过程（包括肿瘤形成）这一事实。对病变进行PAS染色活检和血清学检测对于确立正确诊断至关重要。
