Síndrome Mieloproliferativo Transitorio asociado a Síndrome de Down e Hidrops Fetal: Reporte de caso

BACKGROUND: Transient myeloproliferative Syndrome can be defined as an abnormal proliferation of immature leukemic cells. It presents in newborns with Down syndrome or trisomy 21 mosaicism, as an uncontrolled proliferation of blasts in the megakaryocytic lineage; it resolves spontaneously during the first three months of life. One of the characteristic manifestations is Non-Immune Fetal Hydrops. CASE REPORT: Premature newborn patient adequate for gestational age, born by C-Section due to ultrasound diagnosis of NIHF. At birth, we evidenced phenotypic characteristics of Down syndrome; in addition, the clinical picture and physical examination (respiratory distress, bradycardia, hypotension, prolonged capillary refill, hypotonia, and thrombocytopenia) supported the diagnostic suspicion of neonatal sepsis. The initial management of the patient in the intensive care unit included: mechanical ventilation, vasopressor support, surfactant administration, intravenous antibiotic therapy, furosemide, fentanyl and midazolam, albumin, and vitamin k. EVOLUTION: During his hospital stay, the patient developed acute kidney injury. In addition, we detected leukocytosis and presence of immature cells, anemia and thrombocytopenia, with diagnostic suspicion of congenital leukemia versus MTS, confirmed by flow cytometry. Subsequently, the patient presented elevated bilirubin, with jaundice and subsequent multifactorial cholestasis. The patient was hospitalized for 48 days and after the resolution of the mentioned pathologies, he was discharged. At the follow up, 15 days after discharge, normalization of leucocyte, red blood cell and platelet values confirmed the TMS diagnosis. CONCLUSION: In this case report, the patient developed MTS in relation to Down syndrome and had a complicated clinical course due to all the complications derived from his prematurity, his congenital disease, and the presence of hydrops fetalis and other manifestations of MTS. In the present case, there were criteria of severity, poor prognosis and high risk of mortality, which advantageously do not affect his current clinical condition, but require continuous and strict clinical surveillance. Multidisciplinary management, a high index of suspicion, timely attention to the multiple manifestations and complications, and proper follow-up allowed for a favorable evolution and greater survival in this patient.