自身免疫性胰腺炎的影像学表现

目的回顾性分析自身免疫性胰腺炎(AIP)的临床特点、病理学及影像学表现,以加深对该病的认识。方法2000年3月~2007年8月我院收治的自身免疫性胰腺炎患者10例,均为男性,年龄47~80岁,平均61.3岁。所有患者均行γ球蛋白、免疫球蛋白G(IgG)、类风湿因子及自身抗体检查。所有患者均行CT、超声内镜及B超检查,9例行磁共振胆胰管成像(MRCP),7例行内镜逆行胆胰管成像(ERCP),5例确诊后接受激素治疗。结果临床表现:主要以黄疸(9例)及腹痛(1例)为首发症状,常伴有高γ球蛋白、高IgG及自身抗体阳性,新发糖尿病2例。影像学表现:CT显示9例胰腺弥漫性增大及1例局灶性增大;7例可见胰周炎性渗出,未发现假性囊肿及胰腺钙化;6例胰周淋巴结肿大。4例行增强CT扫描,均可见胰腺实质延迟强化,胰周囊状低密度缘。磁共振成像显示9例胰腺弥漫性增大。MRCP显示6例主胰管弥漫性狭窄和3例主胰管节段性不规则狭窄。B超显示胰腺弥漫性增大9例,胰头部局灶性肿大1例。超声内镜显示9例胰腺弥漫性增大及1例局灶性增大,回声降低。7例ERCP均显示胆总管远端狭窄,近端胆管扩张,4例胰管弥漫性不规则狭窄、3例节段性狭窄。5例经激素治疗后,胰腺影像学异常明显改善。结论AIP是一种特殊类型慢性胰腺炎,具有特征性的影像学表现。正确的诊断有助于临床正确治疗。

Imaging features of autoimmune pancreatitis

OBJECTIVE: To explore the clinical, pathological, and imaging features of autoimmune pancreatitis (AlP). METHODS: The clinical data of 10 patients (all men; aged 47-80 years, mean 61.3 years) with AlP in our hospital between March 2000 and August 2007 were retrospectively analyzed. gamma-globulin, immunoglobulin C (IgG), rheumatoid factors, and autoantibodies were examined for all cases. The imaging findings were reviewed, which included helical computed tomography (CT), endoscopic ultrasonography (EUS), and B-mode ultrasound in all patients, magnetic resonance cholangiopancreatography (MRCP) in 9 patients, and endoscopic retrograde cholangiopancreatography (ERCP) in 7 patients. Follow-up imaging results were available in 5 patients. RESULTS: Clinically, the most common early symptoms included obstructive jaundice (9/10) and non-specific abdominal pain (1/10), accompanied by the elevated levels of serum gamma-globulin, IgG or the presence of autoantibodies. Diabetes mellitus was detected at presentation in 2 patients. imaging findings included: CT showed diffuse (n=9) and focal (n=1) enlargement of pancreas. Minimal peripancreatic stranding was found in 7 patients, with no pancreatic pseudocyst and calcification. Six patients had enlarged peripancreatic lymph nodes. After contrast injection for 4 patients, delayed enhancement of the pancreatic parenchyma was observed, along with low-density capsule-like rim surrounding the pancreas. Magnetic resonance imaging showed diffuse enlargement of pancreas in 9 patients. MRCP showed diffuse (n=6) and segmental (n=3) irregular narrowing of the main pancreatic duct. B-mode ultrasound showed diffuse (n=9) and focal (n=1) enlargement of the pancreas. EUS showed diffuse (n=9) and focal (n=1) enlargement with hypoecho. ERCP showed stricture of distal common bile duct and irregular dilation of proximal bile ducts in 7 patients, diffuse stricture in main pancreatic duct in 4 patients, and segmental stricture in 3 patients. During the follow-up, abnormalities of imaging and serum markers were resolved after steroid therapy in 5 patients. CONCLUSION: AIP is a distinctive type of chronic pancreatitis that shows specific imaging features.