A Case Report of a Congenital Adrenal Hyperplasia in a Seven-day-old Boy

Congenital Adrenal Hyperplasia (CAH) is an inherited autosomal recessive disorder characterized by a deficiency of enzymes involved in the synthesis of cortisol, mineralocorticoids or androgens. Its incidence is 1:18000 and the most common type is 21-hydroxylase deficiency. Classic CAH can result in a salt-losing form or a simple virilizing form.

A 7-day-old newborn was brought to the emergency department for prostration and decreased intake. Forty-six-year-old mother, with 2 previous miscarriages. Pregnancy without intercurrences. Elective caesarean section at 38 weeks, Apgar score 6/9/10 and a low birth weight (2335g). He was lethargic and pale, with a 9% weight loss. Urinalysis with 25 leukocytes, hyponatremia (120mmol/L), hyperkalaemia (9.4mmol/L) with electrocardiographic changes and hypoglycaemia (25mg/dL). He was admitted to Neonatal Intensive Care Unit level II, initiating intravenous antibiotics (ampicillin, gentamicin and cefotaxime), bicarbonate, hydrocortisone and ion-exchange resins. Uroculture was positive for Escherichia coli. Investigation revealed high levels of adrenocorticotropic hormone (566pg/mL), cortisol (28.8mcg/dL) and 17-OHP (241.9ng/mL), confirming the diagnosis of CAH. Fludrocortisone (0.3mg/day) was started. Progressive weaning of intravenous corticosteroid and passage to the oral route according to guidelines, with successive relapses and ionic imbalances. By the 34^th day, clinical and analytical stabilization was achieved under hydrocortisone 61,4mg/m2, NaCl 6,2meq/kg/h and fludrocortisone, and was discharged home. At present, he remains stable, without adrenal crisis and reducing hydrocortisone (22,7mg/m2). The genetic study is underway.

CAH is a serious condition at risk of impending decompensation. Clinical severity and stabilization are related to the initial enzymatic deficit, so corticosteroid doses and the weaning rhythm should be individualized and the patient monitored closely. CAH has non-specific clinical manifestations in newborns, so a high suspicion index is needed facing a presentation before the third week of life with no virilization signs, as in this case, whose severity and precocity were triggered by an infectious event.