Neonatal Hypernatremic Dehydration and Thrombocytopenia: Its Prevalence and Relationship with Prognosis

Background: Understanding the risk factors for neonatal hypernatremic dehydration (NHD) may help to control the problem of these infants. Objectives: In this study, the level of platelets in NHD infants and its relationship with prognosis have been evaluated. Methods: This study consisted of 390 neonates who were referred to the Neonatal Clinic, Emergency Ward and Neonatal Intensive Care Unit in Ghaem Hospital, Mashhad, Iran from 2011 - 2017. Demographic data, symptoms of disease, physical examination, and laboratory investigations were evaluated in these patients. At first, based on the serum sodium level, the infants were divided into two groups: isonatremia (serum sodium level < 150 mEq/L) and hypernatremia (serum sodium level ≥ 150 mEq/L). In the next stage, the infants were divided into two groups: hypernatremic dehydration with normal platelet levels (platelet ≥ 150,000 /mcl) and hypernatremic dehydration occurring with thrombocytopenia (platelet < 150,000 /mcl). In the next step, the NHD infants were followed up using the questionnaire existing in Denver Developmental Test II (DDT II) at 6, 12, 18, 24, 30 and 36 months. Results: Thrombocytopenia was observed in 41% of patients with hypernatremia and 6% of isonatremic infants (P < 0.05). Significant differences were found between the groups of normal platelet and low platelet levels in terms of age, sex, weight loss, blood glucose, sodium, blood urea nitrogen, creatinine, complications and prognosis (P < 0.05). Conclusions: Our findings showed a strong relationship between hypernatremia and thrombocytopenia in NHD infants. There were more complications and worse prognosis in patients with thrombocytopenia (P < 0.05).