ACTIVIDAD N 15 MENDELEY
Artículo Científico Revisión Sistémica
DISCUCIÓN
Only a small population of neonates have been treated with azithromycin and
no major AE has been documented. This systematic review shows that
azithromycin significantly reduces the risk of BPD in neonates and is also
effective in the treatment of chlamydia conjunctivitis. A previous systematic
review has also demonstrated the efficacy of azithromycin in the prevention of
BPD.31 Macrolide antibiotics are inhibitors of ureaplasma. The relationship
between ureaplasma infection and BPD has been explored with varying
outcomes reported from different studies.15 17 32 We have also identified two
off-label studies demonstrating the efficacy of azithromycin against chlamydia
trachomatis in neonates. Previous studies have reported the susceptibility of
chlamydia to azithromycin.33 Azithromycin was administered once daily in all
studies because of its long half-life, which is estimated to be between 26 and 83
h in neonates.25 The dose and duration of treatment with azithromycin varied
across the studies. This may be due to its off-label use and the absence of a
standardised dosing regimen for the drug in this age group. Very few studies
have been conducted in neonates; hence the safety and efficacy of different
dosing regimens for different indications have not been established. The
majority of the AEs reported in preterm neonates were related to prematurity
and were unlikely to be caused by azithromycin. Results from one of the
studies, however, showed that azithromycin had a better safety profile than
erythromycin in neonates. Diarrhoea, abdominal discomfort and reduced
appetite were less frequent in azithromycin treated neonates. In another study,
2% and 3%, respectively, of neonates exposed to azithromycin and
erythromycin within 14 days of life developed IHPS.26 Both erythromycin and
azithromycin are gastric motilin receptor agonists (1–9).34 Activation of these
receptors by erythromycin with consequent increased pyloric contractions has
been hypothesised as a possible cause of pyloric hypertrophy in neonates.35
The association between erythromycin and pyloric stenosis has been
demonstrated in previous studies. High dose and early neonatal exposure to the
drug within the first 14 days of life are known risk factors.36 Azithromycin,
similarly to erythromycin, binds to and activates the motilin receptors.37
Erythromycin is, however, believed to have a stronger gastrointestinal prokinetic
effect than azithromycin.38 These drugs are slightly structurally different, with
erythromycin having a 14-C member heterocyclic ring and azithromycin a 15
member ring.39 The effect of the structural differences on motilin receptor
binding and IHPS requires further exploration. Postnatal exposure to macrolides
from breast milk has also been associated with IHPS.40 Further studies are
required to determine the relationship between neonatal azithromycin use and
IHPS. Although prolonged QTc interval and torsades de pointes had been
reported in azithromycin-treated adults,41 none of the reviewed studies
