This article is from the public account: CC Weekly (ID: cancer-weekly) , author: Zhang Jiao, MD Anderson cancer Center tenured professor

New coronavirus infection continues to worsen and new cases continue to increase . At the same time, cities outside Hubei will usher in the first wave of infection in one to two weeks. Improving the rate of virus detection, early detection, early isolation, and early treatment are key steps in preventing further spread.

However, Because the virus is a new type of virus, the number of detection reagents is not enough, especially in Wuhan . Li Lanjuan, an academician of the Chinese Academy of Engineering and a member of the high-level expert group of the National Health and Medical Commission, said in an interview with CCTV in Wuhan that there are not enough testing reagents in Wuhan at present, so not everyone can be tested. “Early detection, early diagnosis, early isolation, and early treatment cannot be done in Wuhan at this time. I hope that the country will support Wuhan.”

Recently, Dr. Zhang Xiaochun of Zhongnan Hospital of Wuhan University and Professor Zeng Yan of Wuhan University of Science and Technology have called for various channels to adjust the current diagnostic course based on the original test reagents and add low-dose chest CT. As a method of preliminary screening . At the same time, I also assisted some front-line doctors in diagnosis on my social media.

In response to the urgent situation of 100,000 disasters, I analyzed the relevant materials and proposed that the establishment of CT as the diagnostic standard of new pneumonia as soon as possible and increase the detection rate of new crown virus is urgent.

A shortage of nucleic acid testing reagents and false negatives are affecting the diagnosis of patients with new coronary pneumonia

Every diagnostic method has its advantages and limitations. Although 2019-nCoV virus-specific RT-PCR method can be used for diagnosis, it has the following limitations:

  1. When the viral load is not high, its detection rate is relatively low. As a result, false negatives occurred.


  2. Only a positive diagnosis can be made, but the severity of pneumonia and its development process cannot be judged. (but CT imaging can) ;


  3. The shortage of reagents and the quality of new products from major companies need to be studied and improved.


  4. It takes 1 day or more to obtain results after sampling.



    Due to the shortage of test reagents and some false negatives, facing the peak of infections already and coming, under the principle of applying 2019-nCoV specific test reagents as a confirmatory diagnosis, increase chest CT for screening The diagnostic method is imminent.

    If the patient’s respiratory symptoms and CT images meet the coronavirus pneumonia (Refer to the diagnostic criteria provided by the Radiology Department of Wuhan Union Medical College Hospital) . When the detection reagent is confirmed, it should be isolated in time and treated in time. With a history of positive exposure and travel history, a clinical diagnosis of 2019-nCoV pneumonia can be made and corresponding measures taken.

    Preventing micro-stepping is an important principle in the prevention and control of infectious diseases.

    Why do I recommend CT as the diagnostic criteria for new coronary pneumonia?

    • Undiagnosed 2019-nCOV is extremely unfavorable for the prevention and eradication of this disease;


    • Based on available clinical data (Lancet Jan 2020; NEJM Jan. 2020; Lancet Feb. 2020) , the clinical manifestations of most new coronaviruses have relatively typical fever and lower respiratory tract symptoms, and multiple early CT Ground-glass lesions and late lung consolidation (For details, please refer to the recommendations and standards of the Radiology Department of Wuhan Union Medical College Hospital. They are in the front line and have the most say) span>;


    • Although other CT images of viral or bacterial pneumonia overlap with the new coronavirus, the treatment method is similar, and early isolation and treatment is also preferred;

      If a concurrent bacterial infection is suspected, antibiotics can be added for subsequent treatment.

      The advantage of CT testing is immediate, and you can make a judgment immediately. There can be an intuitive image of the severity and development of the disease.

      The limitations are:

      1. There is some overlap with other lung infections;


      2. Early infections may not show significant changes in lung imaging.


      3. Imaging diagnostic standards need to be further improved. However, no diagnostic method in the world is perfect.



        Time is always around, time is life. The relevant departments are urged to formulate the diagnostic principles and standards of CT for detecting patients with new coronary pneumonia as soon as possible, and at the same time introduce diagnostic guidelines to hospitals nationwide.

        In this emergency, CT imaging diagnosis, medical history and clinical manifestations are one of the options for clinical diagnosis 2019-nCoV. At the same time, various diagnosis and treatment technologies were further optimized to overcome difficulties in a short period of time. The establishment of this diagnostic principle is also helpful for other developing countries as a reference.

        With CT diagnosis points (For details, please refer to the recommendation of Department of Radiology, Wuhan University Union Hospital)

        1. Early lesions are mainly distributed in patchy subsegments;


        2. Multiple involvement of multiple lung lobes during progression, with partial consolidation;


        3. Diffuse consolidation of both lungs in severe stage “white lung”.



          Differential diagnosis includes pneumonia caused by other viral or bacterial infections.

          Diagnosis standard map of Radiology Department of Xiehe Hospital:

          This article is from the public number: CC Weekly (ID: cancer-weekly) , author: Zhang Jiao, MD Anderson cancer Center tenured professor < / span>