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Holoprosencephaly and genitourinary anomalies in fetal methotrexate syndrome
J Román Corona-Rivera1, Alejandro Rea-Rosas, Adrián Santana-Ramírez
1Servicio de Genética, División de Pediatría, Nuevo Hospital Civil de Guadalajara Dr. Juan I. Menchaca, Hospital-Escuela, Guadalajara, Jalisco, Mexico. rocorona@cucs.udg.mx
Insights
Prenatal methotrexate (MTX) exposure can cause fetal MTX syndrome (FMS), leading to birth defects. This case highlights previously unreported CNS and genitourinary anomalies associated with FMS.
Area of Science:
- Teratology
- Developmental Biology
- Pediatric Neurology
Background:
- Prenatal exposure to methotrexate (MTX) in the first trimester is a known teratogen.
- MTX exposure can result in fetal death or a spectrum of birth defects known as fetal MTX syndrome (FMS).
Observation:
- A male infant exposed to oral MTX during early pregnancy presented with severe FMS.
- The infant exhibited typical FMS features along with novel central nervous system (CNS) and genitourinary anomalies.
Findings:
- The infant presented with semilobar holoprosencephaly (HPE), congenital penile curvature, vesicoureteral reflux, and hydronephrosis.
- This case confirms holoprosencephaly as a potential feature of MTX teratogenicity and suggests genitourinary anomalies may be characteristic of FMS.
Implications:
- This report expands the phenotypic spectrum of fetal MTX syndrome.
- It underscores the need for thorough evaluation of CNS and genitourinary systems in infants exposed to MTX prenatally.
Abstract:
Prenatal exposure to methotrexate (MTX) in the first trimester may lead to fetal death, and surviving children have increased risks for cranial dysostosis, dysmorphic facies, skeletal malformations, limb defects, growth retardation, and, in some cases, developmental delay, a pattern of defects recognized as fetal MTX syndrome (FMS). We report on a male infant who, in addition to severe FMS, showed previously undescribed central nervous system (CNS) and genitourinary anomalies that contributed to the further delineation. The propositus was born to a G2, 20-year-old mother with an irregular menstrual history. The unplanned pregnancy was complicated by oral MTX treatment (5 mg/day) for suspected systemic lupus erythematosus for 14 days at the 5th week post-conception, as dated by the first trimester sonogram. In addition to the typical features of the FMS, our propositus exhibited congenital penile curvature, vesicoureteral reflux, hydronephrosis, and severe CNS anomalies including semilobar holoprosencephaly (HPE). A single previous report of lobar-type HPE in an infant with FMS led us to confirm that the HPE observed in the propositus is a feature attributable to MTX teratogenicity, although the exact mechanisms of the HPE production need to be further elucidated. Also, this case serves to highlight the presence of genitourinary anomalies in patients with FMS, a fact that requires intentional searches in future patients in order to confirm this as being characteristic of the entity.
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