[2][3] Chloramphenicol works by binding to ribosomal subunits which blocks transfer ribonucleic acid (RNA) and prevents the synthesis of bacterial proteins.
Common signs and symptoms include loss of appetite, fussiness, vomiting, ashen gray color of the skin, hypotension (low blood pressure), cyanosis (blue discoloration of lips and skin), hypothermia, cardiovascular collapse, hypotonia (muscle stiffness), abdominal distension, irregular respiration, and increased blood lactate.
This condition is due to a lack of glucuronidation reactions occurring in the baby (phase II hepatic metabolism), thus leading to an accumulation of toxic chloramphenicol metabolites:[12] Insufficient metabolism and excretion of chloramphenicol leads to increased blood concentrations of the drug, causing blockade of the electron transport of the liver, myocardium, and skeletal muscles.
[6] If left untreated, possible bleeding, renal (kidney) and/or hepatic (liver) failure, anemia, infection, confusion, weakness, blurred vision, or eventually death are expected.
[13] Gray baby syndrome should be suspected in a newborn with abdominal distension, progressive pallid cyanosis, irregular respirations, and refusal to breastfeed.
According to the Drug and Lactation database (LactMed), it states that "milk concentrations are not sufficient to induce gray baby syndrome".
To support the diagnosis, blood work should be done to determine the level of serum chloramphenicol, and to further evaluate chloramphenicol toxicity, a metabolic panel and a complete blood panel including levels of serum ketones and glucose (due to the risk of hypoglycemia) should be completed to help determine if an infant has the syndrome.
[4] Gray baby syndrome has been noted to be dose-dependent as it typically occurs in neonates who have received a daily dose greater than 200 milligrams.
[6] When chloramphenicol is necessary, the condition can be prevented by using the recommended doses and monitoring blood levels,[17][18][19][20] or alternatively, third generation cephalosporins can be effectively substituted for the drug, without the associated toxicity.
[6] Since symptoms of gray baby syndrome are correlated with elevated serum chloramphenicol concentrations, exchange transfusion may be required to remove the drug.
For hemodynamically unstable neonates, supportive care measures such as resuscitation, oxygenation, and treatment for hypothermia are common practices when cessation of chloramphenicol alone is insufficient.
[6] With sepsis being a complication of severe gray baby syndrome, usage of broad-spectrum antibiotics such as vancomycin, for example, is a recommended treatment option.