Factor XII, also called Hageman factor, is an enzyme initiating the coagulation cascade. The main laboratory abnormality, which characterizes patients with factor XII deficiency, is an asymptomatic prolongation in activated Partial Thromboplastin Time (aPTT), whose incidence is relatively low (1/1,000,000 individuals). Factor XIIa plays a double role in the cascade reactions of coagulation. It can activate factor XI, which subsequently activates factor IX (previous intrinsic pathway); however, this is its marginal function. The conversion of plasminogen into plasmin by active factor XII and initiation of fibrinolysis is of greater importance. In the human body, the processes of coagulation and fibrinolysis are constantly in a dynamic equilibrium; therefore, factor XII deficiency can potentially increase the risk of thrombosis [1] . Congenital factor XII deficiency is not associated with a clinical bleeding tendency; it can be identified on a routine coagulation test, such as a prolonged activated partial thromboplastin time [2] . Factor XII is synthesized in the liver, FXII deficiency is rare and may present as an autosomal recessive or acquired disorder. It is generally asymptomatic. Previously, many studies suggested an association between factor XII (FXII) deficiency and autoantibodies to FXII and recurrent pregnancy loses [3] . Although majority of patients with factor XII deficiency show prolonged activated partial thromboplastin time (aPTT), haemorrhagic incidents are not usually associated with the hereditary form of this factor. On the contrary, these patients suffer more often from thromboembolism as did Hageman himself [4] .

Hageman factor was first discovered in 1955 when a routine preoperative blood sample of the 37-year-old railroad brakeman John Hageman was found to have prolonged clotting time in test tubes, even though he had no hemorrhagic symptoms. Hageman was then examined by Dr. Oscar Ratnoff who found that Mr. Hageman lacked a previously unidentified clotting factor. Dr. Ratnoff later found that the Hageman factor deficiency is an autosomal recessive disorder, when examining several related people which had the deficiency. Paradoxically, pulmonary embolism contributed to Hageman’s death after an occupational accident. Since then, case series clinical studies have identified an association of thrombosis and factor XII deficiency, though the pathophysiology of the relationship is unclear. Hepatocytes express blood coagulation factor XII [5] .

Factor XII (Hageman Factor) deficiency is a rare detection, usually persistent prolongations of activated Partial Thromboplastin Time (aPTT) suggests of Hemophilia which we have ruled out in this patient. Patient had no history of taking Warfarin or any other anticoagulation drugs, so the diagnosis was challenging.

The patient had no visible evidence of internal or external bleeding which led us to suspect factor XII deficiency which ultimately was the etiology of prolonged activated Partail Thromboplastin Time (aPTT) in this case.

51-year-old female with a history of Multiple Right Calculi, recurrent sinusitis was incidentally found to have excessively high aPTT. Patient has no history of DM, HTN, PTB, Hepatitis, patient had undergone ESWL for renal calculi and reconstructive nasal surgery for recurrent sinusitis, Patient had no allergic history. The Patient had menarche at the age of 13, menstrual period is around every 28 to 30 days, and the patient is unmarried. The patient has no history of spontaneous bleeding. During Hospital stay patient was managed with Vitamin K and other supportive treatment. Since there was no evidence of internal or external bleeding, the medical management was not difficult. On USG examination, multiple right sided ureteric stone was detected, Urine Routine Examination showed excessive hematuria, Complete Blood Count, Renal Function Test, Liver Function Test all were within normal limits. The patient’s Blood Group is A Positive.

Documented evidence of Persistent elevation of aPTT at our centre is listed in Table 1.

To find out the cause of excessively raised level of aPTT, investigation to measure the concentration of clotting factor was sent which revealed following parameters as listed in Table 2.