Hemorrhagic diathesis is the clinical hallmark of FXIIID, but there is considerable variation in the severity of the disease. While some patients may suffer from life-threatening hemorrhages, others merely show an increased tendency to bleed upon provocation.

On the one hand, FXIIID-associated hemorrhagic diathesis may be apparent at birth and manifest as soft tissue hematoma or umbilical cord bleeding. On the other hand, FXIIID may be suspected in elder adults with an acute-onset tendency to bleed [1]. Regardless of the age of the patient, FXIIID may promote hemorrhages of the skin, which most commonly present as ecchymosis, mucosal hemorrhages such as bleeding gums, and subcutaneous hematomas [2]. Females in fertile age may suffer from menorrhagia and are often unable to carry a pregnancy to term [3]. Genitourinary and gastrointestinal bleedings leading to hematuria, melena, or hematochezia are not typical of FXIIID, but may occur occasionally [4]. Furthermore, FXIIID patients are at increased risks of life-threatening intracranial hemorrhages [5] [6]. It has been estimated that such hemorrhages occur in about a third of FXIIID patients [2]. They may also occur if the patient has shown only mild symptoms in the past [7].

• Surgical Procedure

  Postoperative hematomas are a common complication of surgical procedures. [ahajournals.org]

  Mild (≥ 30% activity): Patients are mostly asymptomatic, but might have problems with bleeding during trauma, a surgical procedure or with pregnancy/delivery. [rarebleedingdisorders.com]

  procedures, or to prevent recurrent bleeding (such as central nervous system or joint hemorrhages).[3] More detailed information about the treatment of factor XIII deficiency is available on the Medscape Reference website. [rarediseases.info.nih.gov]

• Internal Bleeding

  Internal bleeding may occur; about 25 percent of affected individuals experience bleeding in the brain.[1] FXIII deficiency is usually caused by mutations in the F13A1gene, but mutations have also been found in the F13B gene. [rarediseases.info.nih.gov]

• Developmental Disorder

  ICH was another common presentation leading to behavioral and developmental disorders and aphasia. [ncbi.nlm.nih.gov]

• Easy Bruising

  Common symptoms bleeding from the umbilical cord stump at birth nosebleeds (epistaxis) easy bruising bleeding into joints (haemarthrosis) bleeding in the central nervous system (the brain and spinal cord) bleeding in the mouth, particularly after dental [haemophilia.ie]

  Inherited coagulation disorder resulting in life-long bleeding tendency in homozygotes with poor wound healing and easy bruising. Congenital Factor XIII Deficiency. [accessanesthesiology.mhmedical.com]

  Other signs and symptoms of inherited factor XIII deficiency include nosebleeds, bleeding of the gums, easy bruising, problems with wound healing, bleeding after surgery, and abnormal scar formation. [ghr.nlm.nih.gov]

  […] susceptibility Bruise easily Easy bruisability Easy bruising [ more ] 0000978 Congenital onset Symptoms present at birth 0003577 Ecchymosis 0031364 Intracranial hemorrhage Bleeding within the skull 0002170 Reduced factor XIII activity 0008357 Showing [rarediseases.info.nih.gov]

  Your doctor may recommend the test if you have a family history of bleeding disorders or if you have experienced any of the following symptoms: abnormal or excessive bleeding easy bruising heavy or prolonged menstrual periods frequent gum bleeding frequent [healthline.com]

• Vomiting

  Abstract We report the case of a 2-year-old Lebanese male child, known to have congenital factor XIII (FXIII) deficiency, who presented to the emergency department with somnolence and projectile vomiting without any head trauma. [ncbi.nlm.nih.gov]

  People who have congenital factor XIII deficiency should watch for these signs and symptoms in the parts of the body listed below: Symptoms of bleeding in the brain Drowsiness or loss of consciousness Headache or neck ache Nausea and vomiting Sensitivity [rarebleedingdisorders.com]

  Migraine Headache Migraine headache is a type of headache associated with a sensitivity to light, smells, or sounds, eye pain, severe pounding on one side of the head, and sometimes nausea and vomiting. [medicinenet.com]

  “Nonbilious vomiting is the initial symptom of pyloric stenosis. The vomiting may or may not be projectile initially but is usually progressive, occurring immediately after a feeding. Emesis might follow each feeding, or it may be intermittent.” [slidepptx.com]

• Delayed Wound Healing

  They also had prolonged umbilical cord bleeding and history of delayed wound healing. Since childhood, they have been developing spontaneous ecchymotic spots. Three out of four sisters had Factor XIII deficiency. [ncbi.nlm.nih.gov]

  Delayed wound healing and delayed bleedings are other common presentations among these patients. [tandfonline.com]

  Thirty percent of the affected individuals may also experience spontaneous bleeding into the brain (intracranial hemorrhages), about 25% experience poor or delayed wound healing and others may have enhanced bleeding after trauma or surgery. [rarediseases.org]

• Erythema

  אביו סובל מאותה תופעה: Erythema Multiforme. Atopic dermatitis. Acute Urticaria. Angioedema. HSP. “Hereditary angioedema (HAE) is an inherited disease caused by low levels of the plasma protein C1 inhibitor (C1-INH) (Chapter 128). [slidepptx.com]

• Headache

  Migraine Headache Migraine headache is a type of headache associated with a sensitivity to light, smells, or sounds, eye pain, severe pounding on one side of the head, and sometimes nausea and vomiting. [medicinenet.com]

  Common side effects include headache, and pain in the extremities and at the injection site. [hemophilia.org]

  The most common adverse reactions found during the clinical study included headache, pain in the extremities, injection site pain, and D-dimer increase. Efficacy of Tretten was studied in 77 patients treated with 35IU/kg Tretten monthly dose. [clinicaltrialsarena.com]

  The most commonly reported adverse events were headache, pain in the extremities, and injection site pain. [mdedge.com]

• Seizure

  Intracranial haemorrhage can result in neurological sequelae including seizure disorders. In some cases, medically intractable epilepsy led to epilepsy surgery. [ncbi.nlm.nih.gov]

  Seizure and delayed umbilical stump separation each occurred in 5 patients (18.5% each). A total of 3 patients experienced hematoma, and 1 had ecchymosis. [hematologyadvisor.com]

  “Absence seizures do not have a postictal period and are characterized by immediate resumption of what the patient was doing before the seizure. [slidepptx.com]

  Some of the symptoms and warning signs of teen drug abuse include reddened whites of eyes, paranoia, sleepiness, excessive happiness, seizures, memory loss, increased appetite, discolored fingertips, lips or teeth, and irritability. [medicinenet.com]

  They can even be used to help control seizures. As explained by the Center for Substance Abuse Research, these are some of the most commonly prescribed drugs around the world. [sunrisehouse.com]

Anamnestic and clinical data usually agree with hemophilia, but additional analyses are required to identify its cause. Coagulation studies are essential in the diagnosis of any bleeding disorder and may also serve as a starting point in FXIIID patients. In this context, platelet count, fibrinogen level, activated partial thromboplastin time (APTT), prothrombin time (PT), and thrombin time (TT) are usually assessed. In FXIIID, all these values are within reference ranges, so the diagnosis of FXIIID requires a more specific approach [2].

FXIII activity can be quantified by the measurement of ammonia released during an in vitro transglutaminase reaction. This assay comprises the spectophotometric assessment of NAD(P)H levels, which negatively correlate with ammonia release [7]. In order to avoid an overestimation of FXIII activity, FXIIIA-independent ammonia release should be inhibited by means of plasma blanking with an irreversible FXIIIA inhibitor [2] [7]. Otherwise, the efficiency of the transglutaminase reaction involving FXIIIA may be evaluated indirectly by measuring the incorporation of labeled substrate amines into substrate proteins in consecutive reactions. Although this technique is very sensitive, it is also time-consuming and poorly available [7].

While the diagnosis of FXIII relies on the assessment of FXIII activity, the results of assays described so far don't allow for a distinction between deficiency subtypes. The latter requires antigen immunoassays and the determination of FXIII-A2B2, FXIII-A, and FXIII-B antigens. In the rare event of qualitative FXIIID, antigen assays yield normal results for the heterotetramer, for catalytic subunit A and carrier subunit B [1]. Quantitative alterations are found in most cases of FXIIID and allow for a distinction between FXIIID type 1 (deficiency of both subunits) and FXIIID type 2 (deficiency of catalytic subunit A). Sole deficiency of carrier subunit B is exceedingly rare, but reduces the plasma half-life of subunit A and does induce mild hemophilia [1].

However, antigen immunoassay results don't provide information as to the cause of FXIIID. Of course, the age of the patient and their medical history may suggest either inherited or acquired FXIIID, but it still recommended to carry out genetic studies and inhibitor assays to confirm the diagnosis and choose the correct treatment regimen. With regard to the former, sequencing of the whole coding region, the splice sites, and the promoter region should be carried out unless a targeted approach seems feasible: Due to founder effects, certain mutations are especially common among FXIIID patients in determined geographical areas and may first be looked for [7].

FXIIID patients require life-long therapy. Those with residual factor XIII activity <5% should regularly be administered plasma-derived virus-inactivated factor XIII concentrates or recombinant factor XIII to prevent life-threatening hemorrhages. In general, monthly to biweekly factor XIII replacement suffices to prevent bleeding episodes because this coagulation factor has an in vivo half-life of 11-14 days [2]. Because higher residual activity of factor XIII is associated with lower risks of such events, on-demand therapy does usually suffice for patients with factor XIII activity >5% [7]. If neither concentrates nor recombinant factor XIII are available to alleviate acute symptoms of FXIIID, fresh frozen plasma and cryoprecipitate constitute valuable alternatives [4].

Female FXIIID patients should be recommended close monitoring during pregnancy. The regular administration of factor XIII concentrates or recombinant factor XIII has been reported to prevent miscarriage and allows affected women to carry a pregnancy to term. While FXIIID outside of pregnancy aims at raising factor XIII activity to >5%, levels of >30% should be strived for in pregnant women [7]. Additional applications may be required during delivery and to avoid postpartum hemorrhages, though [8].

In preparation for surgery, factor XIII activity should be augmented to >50% [7].

First-line therapy of acquired FXIIID, an autoimmune disorder, also comprises the application of immunosuppressants [9]. To this end, corticosteroids like prednisolone are most frequently administered. They may be combined with cyclophosphamide. In case of an unsatisfactory response, the application of monoclonal antibody rituximab may be considered. Of note, recurrence after the discontinuation of immunosuppressive therapy is possible. While some patients achieve complete remission after a second round of immunosuppressive treatment, others require long-term immunosuppression.

Additional treatment options become available if acquired FXIIID can be related to an underlying disease. In general, this applies to about half of all patients diagnosed with acquired hemophilia [10].

An individual patient's prognosis depends on the severity of the disease, which is directly related to residual factor XIII activity [2]. It is important to note that the severity of hemophilia at a given point in time doesn't necessarily allow to deduce the overall severity of the disease. Patients are to be considered at high risk of future hemorrhages if residual factor XIII activity is <5% [7].

FXIIID is either an inherited disorder or an acquired autoimmune disease:

• The former is inherited in an autosomal recessive pattern and is caused by germline mutations in genes F13A1 and F13B, which encode for subunits A and B of FXIII, respectively. More than 150 mutations in F13A1 and about 15 mutations in F13 B have been reported to date [1] [8]. FXIIID patients may be homozygous or compound heterozygous for pathogenic mutations in genes F13A1 and F13B [8]. Of note, heterozygous carriers may show mild clinical symptoms if their residual factor XIII activity is <30% [1] [2].
• The etiology of acquired FXIIID is still poorly understood. It is triggered by the production of autoantibodies directed against either subunit of FXIIID and frequently occurs concomitantly to malignant neoplasms, infectious diseases, additional autoimmune disorders, drug intake or pregnancy [1] [10]. Autoantibody production may also be provoked by factor XIII administration to treat the congenital form of the disease [2]. However, this side effect has rarely been reported in FXIIID patients [7].

The global incidence of FXIIID is 1 per 2 to 3 million inhabitants, rendering FXIIID the rarest of all rare bleeding disorders [2]. However, higher incidence rates have been observed in areas where consanguineous marriage is common [2]. This especially applies to Iran [11]. Inherited FXIIID is a congenital condition and severe disease is associated with symptoms apparent at birth. By contrast, acquired FXIIID is typically diagnosed in the elder adult. The individual risk of developing this variant of FXIIID increases with age.

A complex network of reactions favoring or inhibiting the formation of blood clots is the basis of hemostasis. Primary hemostasis is achieved via the interaction of platelets with each other and with vessel wall components, and results in the formation of a weak platelet plug. This plug is stabilized during secondary hemostasis, which is initiated by activated thrombocytes or upon endothelial damage. Secondary hemostasis involves a cascade of enzyme activation events that may either follow the intrinsic or extrinsic pathway. Both eventually result in the conversion of prothrombin to thrombin. Thrombin, in turn, is required for fibrinogen cleavage and thus for the production of fibrin, but also catalyzes the calcium-dependent activation of factor XIII to factor XIIIA.

For fibrin to build a resistant fibrin net able to stabilize the weak platelet plug, polymer formation is required and mediated by factor XIIIA. In detail, factor XIII establishes crosslinks between glutamine and lysine residues of the α- and γ-chains of donor and acceptor fibrin monomers. This final step in the common pathway of coagulation isn't taken in individuals suffering from FXIIID.

No recommendations can be given to prevent the formation of autoantibodies directed against factor XIII. By contrast, genetic counseling is a valuable tool to reduce the incidence of congenital FXIIID. If the mutation underlying FXIIID in a certain family is known, prenatal diagnosis becomes feasible. In fact, tests for FXIIID have been part of prenatal diagnosis programs in regions with particularly high incidence rates [11].

Factor XIII, also referred to as fibrin-stabilizing factor, is a zymogen implicated in the common pathway of coagulation, the final steps of blood clotting preceded by both the intrinsic and extrinsic cascades. The common pathway of coagulation includes the activation of factor XIII to factor XIIIA, an enzyme required for the formation of a fibrin net that stabilizes the thrombus. Accordingly, FXIIID patients present with hemorrhagic diathesis. The disease may be congenital or acquired as an autoimmune disease, and manifests at birth or in the elder adult, depending on its etiology. Factor XIII replacement is the mainstay of therapy and may be carried out in a regular manner to prevent life-threatening hemorrhages in patients with very low residual factor XIII activity, or may only be necessary to mitigate bleeding episodes. FXIIID patients who have access to such therapies have a good prognosis, but FXIIID left untreated is associated with a high risk of intracranial bleedings that may entail severe disability or death.

Factor XIII is part of the complex system of reactions favoring or inhibiting the formation of blood clots. In a whole, it may be referred to as the hemostatic network. It assures that blood clots form where it is necessary, while excess thrombus formation is avoided. Patients suffering from factor XIII deficiency (FXIIID) have a tendency to bleed because blood clots cannot be sufficiently stabilized in the absence of this coagulation factor. This so-called hemorrhagic diathesis may manifest as umbilical cord bleeding, soft tissue hematoma, hemorrhages of the skin, and bleeding gums. Women suffering from FXIIID may experience heavy menstrual flow and may be unable to carry a pregnancy to term. Furthermore, FXIIID is associated with an increased risk of life-threatening intracranial hemorrhages.

The disease may be congenital or acquired as an autoimmune disease. Both are very rare disorders, with inherited FXIIID being somewhat more common in areas where consanguineous marriage is practiced. About a third of all FXIIID patients live in Iran. Patients suffering from congenital FXIIID may present symptoms at birth. Autoimmune FXIIID is usually diagnosed in the elder adult. In both cases, treatment relies on the replacement of factor XIII, which may be done administering plasma-derived virus-inactivated factor XIII concentrates, recombinant factor XIII, or - if the former are not available - fresh frozen plasma or cryoprecipitate. In severe cases, during pregnancy, and in preparation for surgery, monthly to biweekly treatment is required. Otherwise, on-demand therapy may suffice. Patients diagnosed with autoimmune FXIIID may additionally be administered immunosuppressants. These drugs diminish the production of antibodies against factor XIII and thereby alleviate the symptoms of FXIIID.

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