Polycythemia in Infants Aged 0-12 Months in Tobruk City: A Secondary Analysis of Follow-Up Care Gaps, Diagnostic Oversights, and Rational JAK2 Mutation Testing Criteria

Abstract

Neonatal polycythemia, defined as a venous hematocrit ≥65%, occurs in 0.4–5% of healthy term newborns globally, with incidence rising to 14.5% in neonatal intensive care settings. While predominantly a physiological adaptation to extrauterine life, persistent cases beyond the neonatal period may signal secondary or, rarely, primary myeloproliferative pathology. This article presents a secondary analysis of an infant cohort (aged 1 day to 1 year) originally reported in a primary cross-sectional study by Mtawil et al. (2026) conducted at Tobruk Medical Centre. This study was conducted to characterize the epidemiological patterns of the infant cohort (n = 90; aged 1 day to 1 year), identify systemic deficiencies in follow-up care, and critically evaluate the role of JAK2 mutation testing in the neonatal population, contextualized against current international evidence. This secondary analysis utilized the infant cohort (n = 90; age range: 1 day to 1 year) from the primary cross-sectional study conducted at Tobruk Medical Centre during 2024–2025. Of these, 50 infants (56%) were true neonates (aged ≤28 days), while the remaining 40 (44%) were aged 1–12 months. Cases were stratified by age group following the original classification, and follow-up practices were evaluated against contemporary international standards. Over half of the cases (56%, n = 50) were identified within the first 28 days of life (the neonatal period), consistent with the physiological hematocrit surge that peaks at 2–4 hours postnatally and declines thereafter. The remaining cases (44%, n = 40) were first identified between 1 month and 1 year of age; because sampling was cross-sectional and single-point, these later-identified cases cannot be characterized as "persistent" neonatal polycythemia, and their longitudinal hematocrit trajectory, follow-up, and diagnostic workup cannot be determined from the available records. This finding contrasts sharply with current international recommendations, which advocate for scheduled repeat hematocrit monitoring, cardiorespiratory observation, and targeted partial exchange transfusion for symptomatic infants with packed cell volume ≥65%. Critical gaps included: lack of documented standardized post-discharge protocols; failure to differentiate primary from secondary polycythemia; inadequate parental education; fragmented interdepartmental care; and lack of documented, selective JAK2 testing criteria for cases identified beyond the neonatal period. Available records did not document serial hematocrit monitoring or partial exchange transfusion in the Tobruk cohort; because the clinical records were incomplete/missing, it was not possible to distinguish whether these procedures were omitted or simply not documented. This secondary analysis confirms that while most cases identified in the neonatal period represent transient physiological adaptation, the 44% of cases first identified after 1 month of age—whose persistence, follow-up, and diagnostic workup could not be assessed from the cross-sectional, single-point data—indicate serious systemic deficiencies in post-discharge care for infants with polycythemia. Drawing on international cohorts and consensus guidelines, the analysis provides evidence-based recommendations for implementing standardized follow-up protocols, enhanced parental education, and rational, red-flag-guided JAK2 testing criteria appropriate to resource-limited settings.