Maternal mesalazine-induced neonatal gastrointestinal bleeding

Area of Science:

• Gastroenterology
• Neonatology
• Pharmacology

Background:

• Ulcerative colitis commonly affects women of reproductive age and can worsen during pregnancy.
• Mesalazine (5-aminosalicylic acid) is a recommended anti-inflammatory treatment for pregnant women with ulcerative colitis.
• Maternal mesalazine crosses the placenta, posing a risk of allergic reactions in the fetus.

Purpose of the Study:

• To investigate the potential for maternal mesalazine to cause fetal sensitization and subsequent allergic enterocolitis in a neonate.

Main Methods:

• A pregnant woman with severe ulcerative colitis received high-dose mesalazine (4,000 mg/day) throughout gestation.
• Neonatal outcomes were monitored immediately after birth, including vomiting and hematochezia.
• Serum mesalazine levels, umbilical cord concentrations, fecal eosinophils, and lymphocyte stimulation tests were analyzed.

Main Results:

• The neonate presented with bloody vomitus and massive hematochezia shortly after birth.
• Elevated maternal and umbilical cord serum concentrations of mesalazine and its metabolite were detected.
• Fecal eosinophilia and positive drug-induced lymphocyte stimulation tests suggested in utero mesalazine sensitization causing allergic enterocolitis.

Conclusions:

• Maternal mesalazine administration during pregnancy carries a risk of fetal sensitization.
• This sensitization can lead to allergic enterocolitis in newborns, mimicking food protein-induced allergic proctocolitis.
• Clinicians should consider the potential for fetal allergic sensitization when prescribing mesalazine to pregnant patients with ulcerative colitis.