Patient's question:
AgeDetailed medical condition and purpose of consultation: On the evening of December 31, due to catching a cold and coughing, I started feeling lethargic from January 1. That same night, I had a high fever of 39.5°C. On the 2nd, I went to see a doctor and received intravenous fluids. I was also prescribed oral Taierxin and Banxia Lu. On the evening of the 3rd, the coughing returned. On the 4th, a lung infection was detected, and my temperature was 37.6°C. The doctor switched me to intravenous Azithromycin, along with oral Kaitran and Bolidongni. On the 4th, my temperature was 37.3°C, and I continued the same medication. The doctor said it would be a 5-day course. On the 5th, my fever subsided, and the doctor said, "Mycoplasma was positive" (based on lung sounds, he said). I was alarmed. My colleague's daughter is 6 years old, and she was also diagnosed with positive Mycoplasma last year.
Doctor's answer:
Hello, considering Mycoplasma pneumoniae pneumonia. Mycoplasma pneumoniae is the smallest microorganism capable of independent life, existing between bacteria and viruses, with a size of 200 nm. It is transmitted through respiratory secretions (such as saliva and nasal discharge) via the air, causing respiratory infections ranging from sporadic to localized outbreaks. It is primarily seen in children and adolescents, but it is also not uncommon in adults, with higher prevalence in autumn and winter.Examinations
(1) Chest X-ray: Characterized by increased pulmonary (interstitial markings) and various morphological infiltrates in the lung parenchyma, more common in the lower lobe. It may also appear as spot-like, patchy, or uniform hazy shadows. Approximately 1/5 of cases show mild pleural effusion. Lung lesions exhibit (diversity), initially presenting as interstitial pneumonia with increased (interstitial markings) and reticular shadows, later developing into spot-like or uniform hazy shadows, deeper near the hilar region and more prominent in the lower lobe. About half of cases are confined to a single lobe or pulmonary segment, sometimes with widespread infiltration and consolidation. Children may show enlarged hilar lymph nodes. A small number of cases have mild pleural effusion. The pneumonia typically resolves within 2–3 weeks, though occasionally it may persist for 4–6 weeks.
(2) Pathogenic Examination: The isolation of Mycoplasma pneumoniae is difficult to apply widely and is of little help in early diagnosis. Sputum, nasal, and throat swabs can be cultured for Mycoplasma pneumoniae, but this requires about 3 weeks. Additionally, antiserum can be used to inhibit its growth, and the absence of hemolysis of red blood cells can confirm a negative culture.
(3) Serological Examination: A serum pathogen antibody titer >1:32 and a Streptococcus MG agglutination test with a titer ≥1:40 are considered positive. A four-fold or greater increase in titer on two consecutive tests holds diagnostic value.