Perioperative discovery of KLKB1 c.451dupT mutation causing prekallikrein deficiency in a Saudi child: A case report of safe surgery despite isolated severe aPTT prolongation

Prekallikrein deficiency, a rare autosomal recessive disorder, results in isolated prolongation of activated partial thromboplastin time (aPTT) without associated bleeding symptoms. This condition often complicates preoperative screenings and can lead to unnecessary testing and healthcare expenditures. We report the first documented case of prekallikrein deficiency in Saudi Arabia, involving an 8-year-old boy referred for orchidopexy. The patient presented with an extremely prolonged activated partial thromboplastin time (aPTT) of up to 298 seconds (initially 152.2 seconds), with a normal prothrombin time (PT). Despite extensive coagulation testing showing elevated factor VIII and normal levels of other intrinsic pathway factors, the prolonged aPTT was corrected fully in a mixing study, suggesting a factor deficiency. Subsequent specialized testing confirmed prekallikrein levels below 15%. Genetic analysis identified a homozygous mutation in the KLKB1 gene, confirming the diagnosis of prekallikrein (Fletcher factor) deficiency. Notably, the patient underwent surgery without the need for fresh frozen plasma (FFP) and without any bleeding complications. This case underscores the importance of a thorough clinical evaluation in patients with isolated prolonged aPTT and highlights the challenges and potential overutilization of resources associated with diagnosing rare coagulation disorders like prekallikrein deficiency. Moreover, it emphasizes the necessity of balancing clinical judgment with laboratory findings to avoid unnecessary preoperative delays and anxiety. This case also illustrates the benign nature of prekallikrein deficiency and the feasibility of safe surgical intervention without hemostatic support in such patients.