Cephalosporins are beta-lactam antibiotics which were first introduced in the 1960s. They are derived from cephalosporin C, which is a natural antimicrobial substance produced by the fungus Cephalosporium acremonium. The antimicrobial spectrum differs for first-, second-and third-generation cephalosporins, but in general activity increases with generation level. Cefuroxime (Zinacef, Glaxo Wellcome), a second-generation cephalosporin, is a commonly used drug in the pediatric population, mainly because of its wide range of antibacterial action and safety.
Case 1The patient was a five-month-old boy, the product of a full-term pregnancy and normal vaginal delivery, with a birth weight of 3.2 kg. He required an incubator for three days because of tachypnea. From the age of 40 days, he had recurent episodes of wheezing, mainly precipitated by upper respiratory tract infections, and resolved with nebulized salbutamol for 3-5 days. At the age of five months, he was admitted with right middle lobe pneumonia and exacerbation of his asthma. His arterial blood gas (ABG) analysis on oxygen showed: pH 7.32, PCO 2 6.02 Kpa, PO 2 12.99 Kpa, and HCO 3 23.1 mmol/L. He was started on intravenous (IV) aminophylline, hydrocortisone 100 mg/kg, nebulized salbutamol, as well as IV cefuroxime and cloxacillin 100 mg/kg each. Bronchodilators were stopped on the fifth day, but on the eighth day of starting antibiotics, he suddenly developed gross abdominal distention, which resulted in increasing tachypnea. This was shortly followed by the passage of watery stools. Investigations showed serum potassium 4.0 mmol/L, sodium 137 mmol/L, and bicarbonate 12 mmol/L. A repeat ABG analysis on room air showed metabolic acidosis: pH 7.26, PCO 2 2.51 Kpa, PO 2 15.72 Kpa, HCO 3 8.2 mmol/L, and saturation 97.3%. Blood and stool cultures yielded no growth. The patient was kept nil by mouth (NPO) and all IV antibiotics were stopped. He showed marked improvement within 48 hours of stopping medications and was discharged home two days later.