Azithromycin is a new macrolide drug, convenient to administer, the efficacy is exact, the gastrointestinal adverse reactions are relatively mild, and it was once a first-line drug for the treatment of mycoplasma pneumonia in adults. So, where does it stand today? What other drugs can we choose for the treatment of mycoplasma pneumonia in adults? Let's take a look.
Changes in the treatment of Mycoplasma pneumoniae pneumoniae
With the large-scale use of macrolide drugs, the resistance of Mycoplasma pneumoniae to macrolide drugs has attracted attention at home and abroad. As early as 2011, the mainland "Expert Consensus on the Diagnosis and Treatment of Community-Acquired Pneumonia in Emergency Adults" recommended [1]: For patients who are clinically suspected or confirmed to have Mycoplasma pneumoniae infection and have not improved significantly after 72 hours of initial treatment with macrolides, it is recommended to adjust the treatment plan, if there is no clear contraindication, change to quinolones or tetracyclines, because there were no research reports on Mycoplasma pneumoniae resistant to these two types of drugs at home and abroad.
Starting with the Guidelines for the Diagnosis and Treatment of Adult Community-Acquired Pneumonia in China (2016 Edition) [2], azithromycin (and clarithromycin) has taken a back seat in the treatment of Mycoplasma pneumoniae pneumonia and replaced it with doxycycline, minocycline, or respiratory quinolones, with macrolides available in regions with low mycoplasma resistance rates. Of course, macrolides are currently the preferred drug for mycoplasma pneumonia in children. (Commonly used mycoplasma pneumonia anti-infective drugs see Table 1)
Table 1. Anti-infective drugs for mycoplasma pneumonia
Doxycycline or Minocycline?
Tetracyclines are broad-spectrum antimicrobials, including G+ and G-aerobic and anaerobic bacteria, Rickettsia, treponemal, mycoplasma, chlamydia, and certain protozoa. Doxycycline and minocycline are the two most commonly used antimicrobials in the clinic.
In terms of antibacterial activity, minocycline is the drug with the strongest antibacterial activity among tetracycline drugs, followed by doxycycline, metacycline, chlortetracycline, tetracycline, and oxytetracycline.
In terms of safety, due to the strong fat solubility of minocycline, high concentration in the central nervous system, vestibular and ototoxicity, it is easy to cause patients with dizziness, dizziness, etc., especially in women. Long-term use can also induce lupus erythematosus and autoimmune hepatitis, resulting in pigmentation of the skin and mucous membranes. Because tetracyclines may cause yellow staining of the permanent teeth, they should only be used in people over 8 years of age.
Overall, minocycline is more antibacterial, but doxycycline is safer. In the drug regimens recommended by the 2019 ATS/IDSA Guidelines for Community-Acquired Pneumonia (CAP)[3], only doxycycline was present, not minocycline, and certainly not mycoplasma pneumonia, but also reflected the amount of evidence-based evidence for the treatment of CAP.
In the treatment of Mycoplasma pneumoniae pneumonia, there is not much literature on how to choose between the two. Clinicians can choose the appropriate drugs based on the price, availability, patient's condition, and whether there are comorbidities in their respective hospitals.
Levofloxacin or moxifloxacin?
At present, the commonly used respiratory quinolones in clinical practice are levofloxacin and moxifloxacin, both of which are broad-spectrum antibacterial drugs, levofloxacin is listed earlier than moxifloxacin, and has more experience in clinical application. The activity of the two is comparable to that of Mycoplasma pneumonia, and they have the same recommended status in the treatment of Mycoplasma pneumoniae pneumonia, but there are still major differences in other aspects (see Table 2).
Quinolones have adverse effects of damaging animal cartilage and are contraindicated in people under 18 years of age. It also has central adverse reactions, and should be used with caution in people with central nervous system diseases such as epilepsy. Since quinolones can form complexes with polyvalent metal ions (magnesium, zinc, iron, aluminum ions, etc.), it should also be avoided during medication and drugs containing the above metal ions.
Table 2. Levofloxacin versus moxifloxacin
How to choose the drug for Mycoplasma pneumoniae pneumonia?
Based on the consensus of CAP guidelines at home and abroad, it seems that respiratory quinolones are more favored. Taking the 2019 ATS/IDSA CAP guidelines as an example, β-lactam plus doxycycline is used as an option for azithromycin or fluoroquinone intolerance or contraindications (conditional recommendation, low-quality evidence), while respiratory quinolones alone are strongly recommended for both outpatient and inpatient patients.
But these do not mean that respiratory quinolones are superior to tetracyclines, perhaps simply because of the larger evidence and less data on the treatment of pneumonia by tetracyclines. In a study of 65 patients with CAP [4], intravenous infusions of doxycycline 100 mg twice daily were superior to levofloxacin 500 mg once daily.
In an open-label randomized trial [5], intravenous doxycycline 100 mg twice daily was associated with faster reactivity and fewer antibiotic changes compared to the standard antibiotic regimen.
Therefore, which of the two is better or worse, how to choose still needs to be determined according to the actual situation.
For example, patients over 8 years of age and under 18 years of age may choose doxycycline or azithromycin; patients over 18 years of age can choose doxycycline or respiratory quinolones;
Tetracyclines may be more appropriate than quinolones in patients with central nervous system disorders (e.g., epilepsy), and quinolones may be more appropriate than tetracyclines in patients with vestibular disorders (e.g., dizziness, vertigo).
In the case of hepatic insufficiency, quinolones are best selected for levofloxacin, which is excreted by the kidneys, and doxycycline or moxifloxacin metabolized by the liver and kidney bichanter can be selected in patients with renal insufficiency.
For pregnant women, neither tetracycline nor quinolones can be chosen, and azithromycin may be more appropriate.
In short, clinicians need to make the most beneficial drug choices based on the patient's age, comorbidities, organ function, drug resistance risk, adverse drug reactions, drug availability and economics, and other factors.
bibliography:
Infectious Disease Group, Respiratory Diseases Branch of Chinese Medical Association. Expert consensus on the diagnosis and treatment of Mycoplasma pneumoniae pneumonia in adults[J]. Chinese Journal of Tuberculosis and Respiratory Disease, 2010, 33(9):3.
Qu Jieming, Cao Bin. Guidelines for the Diagnosis and Treatment of Adult Community-Acquired Pneumonia in China (2016 Edition)[J]. Chinese Journal of Tuberculosis and Respiratory Disease,2016,39(04):253-279.
[3] Olson G, Davis AM. Diagnosis and Treatment of Adults With Community-Acquired Pneumonia. JAMA. 2020 Mar 3;323(9):885-886. doi: 10.1001/jama.2019.21118. PMID: 32027358.
[4] Mokabberi R, Haftbaradaran A, Ravakhah K. Doxycycline vs. levoflfloxacin in the treatment of community-acquired pneumonia. J Clin Pharm Ther 2010;35:195–200.
[5] Ailani RK, Agastya G, Ailani RK, Mukunda BN, Shekar R. Doxycycline is a cost-effective therapy for hospitalized patients with communityacquired pneumonia. Arch Intern Med 1999;159:266–270.
Planner: Mei Chao
This article was first published on Lilac Garden's professional platform: Breathing Time