Congenital syphilis in a preterm newborn with gastrointestinal disorders and postnatal growth restriction
Authors: Serra Gregorio , Carta Maurizio , Di Pace Maria Rita , La Sala Eleonora , Piro Ettore , Salerno Sergio , Schierz Ingrid Anne Mandy , Vassallo Alessia , Giuffrè Mario , Corsello Giovanni 
Published: December 2022

Abstract
Background
Congenital syphilis (CS) depends on the placental transmission of Treponema pallidum (TP) spirochetes from an infected mother to fetus during pregnancy. It shows a wide clinical variability with cutaneous and visceral manifestations, including stillbirths, neonatal death, and asymptomatic cases. Preterm infants with CS may have more severe features of disease than the term ones, due to the combined pathogenic effect of both CS and prematurity.

Case presentation
We report on a female preterm (32+6 weeks of gestation) newborn showing most of the typical CS manifestations, in addition to gastrointestinal disorders including feeding difficulties, colon stenosis and malabsorption leading to postnatal growth restriction. The mother resulted positive at the syphilis screening test of the first trimester of pregnancy, but she did not undergo any treatment. At birth, our newborn was VDRL positive (antibody titer four times higher compared to the mother), and she was treated with intravenous benzathine benzylpenicillin G for 10 days (50,000 IU/Kg three times per day). Poor tolerance to enteral nutrition (abdominal distension, increased biliary type gastric secretions) was observed. A barium enema X-Ray identified a colon stenosis within the descending tract. However, the poor general conditions due to a concurrent fungal sepsis did not allow to perform any surgical procedure, and a conservative approach with total parenteral nutrition was started. The following evolution was marked by difficulties in enteral feeding including refusal of food and vomiting, to which also contributed the neurological abnormalities related to a perinatal asphyxia, and the affective deprivation for the physical absence of the mother during hospitalization. At 5 months of age, after the introduction of an amino acid-based formula (Neocate LCP Nutricia ®), an improvement of enteral feeding was observed, with no further and significantly decreased episodes of abdominal distension and vomiting respectively, and regular stool emission. A psychological support offered to the family allowed a more stable bond between the mother and her baby, thus providing a significant additional benefit to food tolerance and growth. She was discharged at 5 months of age, and included in a multidisciplinary follow-up. She at present shows global growth delay, and normal development apart from mildly increased tone of lower limbs.

Conclusions
Our report highlights less common clinical CS manifestations like gastrointestinal disorders including feeding difficulties, colon stenosis and malabsorption leading to postnatal growth delay. Moreover, it underlines how prematurity may worsen the clinical evolution of such congenital infection, due to the additional pathogenic effect of possible associated diseases and/or conditions like sepsis, hypoxic/ischemic injury, or use of drugs. CS may be observed also in high-income countries, with high rates of antenatal screening and availability of prenatal treatment. A multidisciplinary network must be guaranteed to the affected subjects, to ensure adequate care and improve the quality of life for patients and their families.