Nowadays, many people are nervous about superimposed infections or mixed infections, and many doctors think that it is a mixed infection as soon as they see several positive tests, and they think that it is the pathogen that caused the disease. In fact, sometimes it is over-interpretation, I remember that some time ago, a 3-year-old girl in Hangzhou, with a high fever that did not go away, found out the news ** that the child was infected with "5 viruses" at the same time. In fact, there are only three viruses: syncytial virus, rhinovirus, adenovirus, one Mycoplasma pneumoniae, and Haemophilus influenzae.
I think unless the child has a low congenital immunity, it is unlikely that they will be infected with 5 pathogens at the same time. Mycoplasma pneumoniae nucleic acid positive, or it may be infected with Mycoplasma pneumoniae some time ago or "left behind corpses" after pneumonia**, Haemophilus influenzae is a common pathogen in the respiratory tract of many children, or it may be that sinusitis refluxes after viral infection leads to throat swab collection of pathogens. Rhinovirus is present in nasal secretions for 5-7 days, but may persist in the nasopharynx for up to 2-3 weeks, so it is possible to have one to two pathogens that cause high pneumonia fever in girls, and it is unlikely that five pathogens are infected.
Today, Dr. Ke shares three cases of testing positive for Mycoplasma pneumoniae without needing. Share it with you, I hope it will inspire you. One. Case 1
The girl, 3 years old, had a fever for one day, a body temperature of about 39 degrees Celsius, accompanied by little cough, good spirits, no vomiting and diarrhea, but the blood routine was tested for hypersensitive CRP and Mycoplasma pneumoniae antibodies.
Routine blood count with normal hypersensitive CRP and Mycoplasma pneumoniae antibodies (IgM and IgG), both of which are positive, and the doctor thinks it is Mycoplasma pneumoniae infection, administered azithromycin**.
I said: One day of fever, Mycoplasma pneumoniae IgM has not been produced, if it is produced, then IgG is even more unlikely to be produced within 1 day of fever, which is not in line with the actual situation of detection.
From the expert consensus on laboratory diagnosis standards and clinical practice of Mycoplasma pneumoniae infection in children in China.
Qualitative testing is the primary screening.
MP-IgM: It is an early antibody that appears after infection, appears 4-5 days after infection, peaks in 2-3 weeks, and lasts for 1-3 months or even longer. Immunodeficiency and imperfect immune function (infants and young children) may have false-negative or low-titer antibody MP-IgG: it appears about 14 days after infection, and the concentration reaches its peak at the 5th to 6th week, with a long (more than 6 months) maintenance time.
Two. Case 2 was a 7-year-old boy who had a sputum cough for 7 days, had a poor cough, had no fever, and tested positive for the quantitative titer of Mycoplasma pneumoniae. Considered Mycoplasma pneumoniae infection, azithromycin** is given.
IgG is much larger than IgM, indicating the recovery period of the disease, usually within 3-4 weeks of onset, the child's cough is only one week, and the other is sputum production, not dry cough and spasmodic cough, so it cannot be considered as a current infection.
Three. Case 3 was a 4-year-old boy with a 1-day high fever who had no symptoms of cough and runny nose, but was given a complete blood test and hypersensitivity CRP and SAAThe white blood cells are normal, the absolute value of lymphocytes is low, the CRP is normal, the SAA is slightly high, I said that in the flu season, within 48 hours of fever, it is very supportive of the flu, and oseltamivir** is given. The child has a recurrent body temperature, exertion, loss of appetite, and occasional cough.
The follow-up visit explained to the parents whether the pathogen should be clarified, and 7 respiratory nucleic acids were done: positive for influenza A nucleic acid, positive for Mycoplasma pneumoniae nucleic acid, and negative for the new crown. Does that mean it's a mixed infection?
Not necessarily, because there was no severe cough, I had Mycoplasma pneumoniae pneumonia in October, and Mycoplasma pneumoniae nucleic acid PCR would continue to be positive for a period of time, so azithromycin was not given**.
Although they are all small clinical cases, it may be very simple for professional doctors, but it may not be for general practitioners or doctors who do not learn and do not have surgery, they may think that they have found ** when they see the test sheet, and they do not ask for medical history, nor do they combine it with clinical practice, and they start to use azithromycin when they see a positive report of Mycoplasma pneumoniae. I don't know if you have encountered a similar situation?If you think the article is helpful to you, please share it with your friends and like it, so that more parents can understand children's respiratory diseases and related popular science knowledge.