新生儿衣原体肺炎的临床及影像表现特点分析

Clinical and imaging features of neonatal chlamydial pneumonia

目的总结新生儿衣原体肺炎的临床及影像学特点，以提高对该病的认识水平。方法回顾性分析经血清学确诊为新生儿衣原体肺炎的17例患儿的临床及影像学资料。其中男11例、女6例。足月儿16例，过期产儿1例。发病年龄9．0-28．0d，平均（16．8±5．8）d。17例均行胸部X线摄片检查；其中13例行CT检查。所有患儿均经间接酶联免疫吸附法检测衣原体IgM及IgG抗体。结果17例患儿均以无热性呼吸道症状为主要表现，血清学衣原体抗体检查均为阳性。X线胸片表现双侧肺过度通气10例次；广泛小结节及网格影10例次（类粟粒结核改变7例次，实变9例次）。CT表现为肺内间质网织结节影13例次，结节影大小、密度及分布不甚均匀，以胸膜下结节影（11例次）及融合结节（10例次）多见；两肺过度充气10例次，合并实质浸润12例次，支气管血管束增厚10例次，磨玻璃影5例次，无胸膜渗出及纵隔淋巴结肿大。结论新生儿衣原体肺炎影像以双肺过度充气和弥漫网织颗粒影为主要表现。临床主要表现为无热性呼吸道感染症状。临床和影像学结合可以高度提示新生儿衣原体肺炎的诊断。

Objective To study the clinical and imaging features of chlamydial pneumonia in newborns. Methods Medical records, chest X-Ray and CT findings of 17 neonates with chlamydia pneumonia were reviewed. The age was ranged from 9. 0 to 28.0 days with mean of （ 16. 8 ± 5.8 ） days. There were 11 males and 6 females. Sixteen were full term infants and one was born post term. All babies were examined with chest X-ray film, and 13 patients also underwent chest CT scan. Serologic test using immunofluorescence method for Chlamydia IgG and IgM antibodies were performed in all patients. Results All newborns presented with cough but without fever. Positive results of the serologic tests were demonstrated. Chest films showed bilateral hyperventilation in 10 patients, diffuse reticular nodules in 10 patients including nodules mimicking military tuberculosis in 7 patients, and accompanying consolidation in 9 patients. CT features included interstitial reticular nodules in 13 patients with size, density, and distribution varied. Subpleural nodules （ 11 patients） and fusion of nodules （ 10 patients） predominated. Bilateral hyperinflation was found in 10 patients,which combined with infiltration in 12 patients, thickening of bronchovascular bundles in 10 patients, and ground glass sign in 5 patients. No pleural effusion and lymphadenopathy was detected in any patient. Conclusions Bilateral hyperinflation and diffuse interstitial reticular nodules were the most common imaging features of neonatal chlamydial pneumonia. The main clinical characteristic of neonatal chlamydial pneumonia is respiratory symptoms without fever, which is helpful to its diagnosis.