- Skin rash (HP:0000988): A red eruption of the skin. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:49566)
- Acrocyanosis (HP:0001063): Bluish discoloration of the skin of the hands or feet. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:49566)
- Thrombocytopenia (HP:0001873): A reduction in the number of circulating thrombocytes. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:49566)
- Abnormal thrombosis (HP:0001977): Venous or arterial thrombosis (formation of blood clots) of spontaneous nature and which cannot be fully explained by acquired risk (e.g. atherosclerosis). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:49566)
- Immune dysregulation (HP:0002958): Altered immune function characterized by lymphoid proliferation, immune activation, and excessive autoreactivity often leading to autoimmune/inflammatory complications. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:49566)
- Prolonged partial thromboplastin time (HP:0003645): Increased time to coagulation in the partial thromboplastin time (PTT) test, a measure of the intrinsic and common coagulation pathways. Phospholipid, and activator, and calcium are mixed into an anticoagulated plasma sample, and the time is measured until a thrombus forms. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:49566)
- Reduced protein S activity (HP:0004855): An abnormality of coagulation related to a decreased concentration of vitamin K-dependent protein S. Protein S is a cofactor of protein C. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:49566)
- Disseminated intravascular coagulation (HP:0005521): Disseminated intravascular coagulation is characterized by the widespread activation of coagulation, which results in the intravascular formation of fibrin and ultimately thrombotic occlusion of small and midsize vessels. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:49566)
- Reduced protein C activity (HP:0005543): An abnormality of coagulation related to a decreased concentration of vitamin K-dependent protein C. Protein C is activated to protein Ca by thrombin bound to thrombomodulin. Activated protein C degrades factors VIIIa and Va. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:49566)
- Abnormal blistering of the skin (HP:0008066): The presence of one or more bullae on the skin, defined as fluid-filled blisters more than 5 mm in diameter with thin walls. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:49566)
- Prolonged prothrombin time (HP:0008151): Increased time to coagulation in the prothrombin time test, which is a measure of the extrinsic pathway of coagulation. The results of the prothrombin time test are often expressed in terms of the International normalized ratio (INR), which is calculated as a ratio of the patient's prothrombin time (PT) to a control PT standardized for the potency of the thromboplastin reagent developed by the World Health Organization (WHO) using the formula: INR is equal to Patient PT divided by Control PT. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:49566)
- Elevated circulating C-reactive protein concentration (HP:0011227): The concentration of C-reactive protein in the blood circulation is above the upper limit of normal. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:49566)
- Hypofibrinogenemia (HP:0011900): Decreased concentration of fibrinogen in the blood. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:49566)
- Macule (HP:0012733): A flat, distinct, discolored area of skin less than 1 cm wide that does not involve any change in the thickness or texture of the skin. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:49566)
- Decreased erythrocyte sedimentation rate (HP:0025022): A reduced erythrocyte sedimentation rate (ESR). The ESR is a test that measures the distance that erythrocytes have fallen after one hour in a vertical column of anticoagulated blood under the influence of gravity. The ESR is a nonspecific finding. A decreased ESR may be seen in polycythemia or in certain blood diseases in which red blood cells have an irregular or smaller shape that causes slower settling. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:49566)
- Erythematous macule (HP:0025475): A macule (flat, distinct, discolored area of skin less than 1 cm wide that does not involve any change in the thickness or texture of the skin) with a red or reddish color often associated with inflammation or irritation. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:49566)
- Shock (HP:0031273): The state in which profound and widespread reduction of effective tissue perfusion leads first to reversible, and then if prolonged, to irreversible cellular injury. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:49566)
- Macular purpura (HP:0031365): Purpura that is flat (non-palpable, not raised). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:49566)
- Gangrene (HP:0100758): A serious and potentially life-threatening condition that arises when a considerable mass of body tissue dies (necrosis). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:49566)
- Hepatic failure (HP:0001399). Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:49566)
- Intracranial hemorrhage (HP:0002170): Hemorrhage occurring within the skull. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:49566)
- Neoplasm (HP:0002664): An organ or organ-system abnormality that consists of uncontrolled autonomous cell-proliferation which can occur in any part of the body as a benign or malignant neoplasm (tumor). Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:49566)
- Internal hemorrhage (HP:0011029): The presence of hemorrhage within the body. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:49566)
- Sepsis (HP:0100806): Sepsis is defined as life-threatening organ dysfunction caused by a dysregulated host response to infection. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:49566)
- Pyoderma gangrenosum (HP:0025452): A deep skin ulcer with a well defined border, which is usually violet or blue. The ulcer edge is often undermined (worn and damaged) and the surrounding skin is erythematous and indurated. The ulcer often starts as a small papule or collection of papules, which break down to form small ulcers with a so called cat's paw appearance. These coalesce and the central area then undergoes necrosis to form a single ulcer. Evidence: TAS. Frequency: Very rare (HP:0040284). (ORPHA:49566)
These phenotypes are associated with the disease Acquired purpura fulminans (ORPHA:49566).