结节肿块型肺隐球菌病CT特征分析

Analysis of CT features of nodular or mass-like type of pulmonary cryptococcosis

目的分析结节肿块型肺隐球菌病（PC）的cT特征，以提高对本病的诊断水平。方法回顾性分析福建省福州肺科医院经病理确诊的52例结节肿块型肺隐球菌病的CT表现。患者均行胸部屏气MSCT检查，其中19例行CT增强扫描。分析病灶数目、大小、分布、病灶密度及增强表现、CT伴随征象等。结节、肿块型病灶的各种CT伴随征象间差异比较采用χ2检验、连续校正χ2检验或Fisher确切概率法。结果52例患者中，单发结节或肿块21例，多发结节或肿块31例，共计206个病灶。其中结节病变172个，肿块病变34个，以下叶（73．3％，151／206）、肺野外带或胸膜下（87．4％，180／206）多见。CT平扫示病灶多数密度较实且均匀，占74．7％（154／206）。19例行胸部CT增强扫描，共95个病灶，其中病灶均匀强化61个（64．2％）、中度强化86个（90．5％）。结节、肿块型病灶均伴随多种CT征象，晕征、近端支气管充气征、空泡或空洞、分叶征、毛刺征、胸膜凹陷征、血管集束征分别为122（59．2％）、66（32．0％）、31（15．0％）、52（25.2％）、27（13．1％）、16（7．8％）、4个（1．9％）。结节和肿块对比，前者分叶征发生率高于后者，二者差异有统计学意义（χ2=13．750，P=0．001），肿块近端支气管充气征和空泡或空洞发生率高于结节，二者差异有统计学意义（χ2值分别为19．957、5．295，P值均〈0．05），其余CT伴随征象间比较差异无统计学意义（P值均〉0．05）。结论结节肿块型肺隐球菌病好发于右肺、下叶、肺野外带或胸膜下，晕征和近端支气管充气征是其较为特征性的CT表现。

Objective To investigate the CT features of nodular or mass-like type pulmonary cryptococcosis （PC）. Methods A total of 52 cases with nodular or mass-like type PC confirmed by pathological examinations at Fuzhou Pulmonary Hospital of Fujian from January 2008 to December 2012 were studied. Each patient underwent a breath-hold MSCT scan and contrast enhanced CT was performed in 19 patients. The data including lesion size, number, distribution, density, performance of enhanced CT scan and accompanying signs were analyzed. Each CT accompanying sign was compared between nodular lesions and mass-like lesions using χ2 test, continuous correction χ2 test or Fisher exact test. Results Of all the 52 patients, pulmonary cryptococcosis was consisted single nodules/masses （21 cases） and multiple of nodules/masses （31 cases）. There were total 206 lesions with 172 nodules and 34 masses. The lesions were mainly found in lower lobe （73.3%, 151/206） and outer zone or subpleura （87.4%, 180/206）of lung. Plain CT scan showed the densities of most lesions were solid and uniform（74.7%, 154/206）. A total of 95 lesions were detected in the 19 patients with contrast enhanced CT, in which 61 lesions （64.2%） showed homogeneous enhancement and 86 lesions （90.5%） showed moderate enhancement. Nodular or mass-like lesions accompanied by many CT signs including halo sign （59.2%, 122/206）, air bronchogram （32.0%, 66/ 206）, pulmonary cavity or vocule sign （15.0%, 31/206）, lobulation sign （25.2%, 52/206）, spicule sign （13.1%, 27/206）, pleural indentation（7.8%, 16/206） and vascular cluster （1.9%, 4/206）. Compared with mass-like lesions, lobulation sign was more frequently observed in nodular lesions （χ2=13.750, P=0.001 ）, whereas air bronchogram and pulmonary cavity orvocule sign were less frequently observed （χ2=19.957, P= 0.001; X2=5.295, P=0.021, respectively）. No significant statistically differences were detected in other CT signs between them （P〉0.05）. Conclusions PC lesions usually occur in right lung, lower lobe and close to the pleura. Halo sign and air bronchogram are the characteristic findings of CT manifestations in nodular or mass-like type PC.