PB0602 - Compound Heterozygous congenital Protein C deficiency: Report of a challenging case with recurrent purpura fulminans treated with Protein C concentrations: Case Report

Background: Congenital protein C deficiency is a rare inherited disorder caused by alterations in the protein C gene (PROC) associated with an increased risk of developing thrombosis. Patients with biallelic PROC variants have more severe symptoms, typically causing purpura fulminans with severe venous thromboembolism in the neonatal period.

Aims: To understand clinical courses, genetic studies and treatment options of congenital protein C deficiency patient.

Methods: Herein, we present a case of a female newborn with protein C deficiency

Results: An eleven-day-old female newborn was transferred to King Chulalongkorn Memorial Hospital due to progressive necrotic skin lesions. She was born full-term with an average birth weight. She developed the first purplish skin lesion on her left buttock since postnatal day 1. She was initially treated with antibiotics under the impression of early-onset neonatal sepsis with disseminated intravascular coagulation (DIC), however, her skin lesions worsened at the left buttock and rapidly progressed to the right buttock, right forearm, left hand, right thigh, right leg and back of her head. The initial investigation test results were unremarkable except for high D-dimer levels of >10,000 ng/mL. The protein C activity was remarkably decreased below 10%, in the same way with the protein C antigen was below 1%, from which we diagnosed protein C deficiency. Computed tomography venography of the brain showed a tiny hemorrhage without gross evidence of thrombosis. Molecular analysis revealed compound heterozygous likely pathogenic variants in the PROC gene. After the diagnosis of protein C deficiency, FFP transfusions and LMWH were started. Protein C concentrate replacement therapy was initiated at the age of 3 months.

Conclusion(s): Severe protein C deficiency can manifest as severe purpura fulminans since the neonatal period. Early recognition and appropriate treatment with protein C concentrate replacement may improve clinical outcomes. Management remains a challenge, especially for centers without access to protein C concentrate.