P3.107: Pregnancy Essentials: Folic Acid, Check-ups, and… Bug Spray? A Case of Congenital Dengue in the Ecuadorian Amazon

Introduction: Dengue, caused by the dengue virus and transmitted by Aedes aegypti mosquitoes, is common in tropical and subtropical regions but rare in neonates. Diagnosis is challenging due to non-specific symptoms that mimic other conditions. Clinical suspicion is key for early diagnosis. This case of congenital dengue, initially managed as neonatal sepsis, highlights the need for a broad differential in neonates born to mothers from tropical regions.

Case Description: A 3-day-old male from the Ecuadorian Amazon region, born preterm (ex-35 weeks) via vaginal delivery following a febrile illness near delivery, was transferred to the NICU for increased work of breathing. He was started on CPAP and empiric antibiotics (ampicillin/gentamicin) pending a sepsis rule-out for suspected neonatal sepsis. The patient developed abdominal distension, irritability, fever, jaundice, and lethargy. Phototherapy was started, and antibiotic therapy was switched to cefepime and amikacin to broaden coverage. Abdominal X-rays to evaluate necrotizing enterocolitis were unrevealing. An orogastric tube was placed, and sanguinolent residue was observed on suction.

On day 6, with no improvement, the patient was transferred to a tertiary care hospital. Physical examination revealed hemodynamic instability, flat fontanelles, jaundice (Kramer II), and abdominal distension. Laboratory tests showed thrombocytopenia (6,000 K/uL) and elevated CRP. A repeat abdominal X-ray (Figure 1) showed dilated bowel loops and pneumatosis. Platelets were transfused, and repeat cultures were taken due to persistent fever.

On day 12, laboratory tests showed platelets at 19,000 K/uL, anemia, persistently elevated CRP, and negative cultures. Given the mother’s fever history and residence, extensive testing, including repeat TORCH and dengue virus IgM, was performed. Both the patient and mother were positive for dengue IgM, confirming congenital dengue due to in-utero transmission and prompting antibiotic discontinuation (Figure 2).

He was discharged within 10 days of the diagnosis with recovered platelet counts (64,000 K/uL) and no complications.

Discussion: Congenital dengue, though rare, is an important consideration in newborns, especially in endemic areas. Diagnosis is challenging due to non-specific symptoms and often relies on the maternal history of illness. In this case, the patient’s disease course, combined with the maternal history, led to the diagnosis. Vertical transmission should be suspected in infants born to mothers in endemic regions or with fever around delivery. Preterm birth is a common complication. Early recognition and management are key to improving outcomes.

Conclusion: Physicians should consider tropical diseases in their differential, especially in endemic regions or among recent migrants. A thorough maternal history helps narrow the differential and guide management. This case emphasizes the need for a broad differential, even in non-endemic areas, and highlights the importance of public health strategies to address tropical infections during pregnancy.