Presentation on theme: "Approach to child with purpura Ahmed S.Barefah KAAU,MBBS."— Presentation transcript:
Approach to child with purpura Ahmed S.Barefah KAAU,MBBS
Questions What is the definition of purpuric rash? What are the causes of purpura? How to approach such a case?
Definition red, nonblanching maculopapular lesions caused by intradermal capillary bleeding. classified as o petechiae (pinpoint hemorrhages less than 2 mm in greatest diameter), o purpura (2 mm to 1 cm) or o ecchymoses (more than 1 cm). results from the extravasation of blood from the vasculature into the skin or mucous membranes.
Thrombocytopenia may be caused by – increased platelet destruction Immune nonimmune – decreased platelet production Congenital Acquired – sequestration of platelets.
Immune Thrombocytopenia Idiopathic (immune) thrombocytopenic purpura – by far the most common etiology of thrombocytopenia in childhood. – caused by the development of IgG autoantibodies to platelet membrane antigens as a result of an unbalanced response to an infectious agent or autoimmunity – sudden onset of bruises, purpura, mucosal hemorrhage and petechiae in a child who is otherwise in excellent health.
ITP – antecedent viral infection is common. – The peak incidence is between two and four years of age. – 80 to 90 percent of children recovering within six to 12 months. – Chronic idiopathic thrombocytopenic purpura is more likely to present in teenage girls and children with underlying immune disorders. It has a more insidious onset
Immune Thrombocytopenia Drugs – penicillin, valproic acid (Depakene), quinidine, sulfonamides, cimetidine (Tagamet) and heparin. Post-transfusion purpura – acute onset of thrombocytopenia approximately five to 14 days after a transfusion. Rarely – HIV, CMV, HSV – 10% of SLE cases
Non-Immune Thrombocytopenia hemolytic-uremic syndrome – triad of microangiopathic hemolytic anemia, thrombocytopenia and acute renal injury. – infection by verocytotoxin-producing Escherichia coli thrombotic thrombocytopenic purpura – occurs more often in adults, and neurologic (rather than renal) symptoms are more prominent
Non-Immune Thrombocytopenia disseminated intravascular coagulopathy – overwhelming sepsis, incompatible blood transfusion, snake bite, giant hemangioma and malignancy. Purpura fulminans – acute, often lethal syndrome of DIC. – may develop because of a severe bacterial infection, notably meningococcal disease, or because of protein C or S deficiency
Decreased Platelet Production Congenital – Thrombocytopeniaabsent radii (TAR) syndrome inherited as an autosomal recessive trait – Fanconi anemia pancytopenia, hyperpigmentation and café au lait spots, short stature, skeletal abnormalities – Wiskott-Aldrich syndrome
Decreased Platelet Production Acquired – Bone marrow suppression Drugs such as alkylating agents, antimetabolites, anticonvulsants, chlorothiazide diuretics and estrogens Infection as viral and bacterial infections, especially septicemia and Intrauterine infection with TORCH organisms – Bone marrow infiltration patients with leukemia, histiocytosis, storage diseases, neuroblastoma, myelofibrosis and osteopetrosis
Sequestration of Platelets Splenomegaly or giant hemangioma can result in thrombocytopenia because of platelet sequestration. The association of thrombocytopenia and giant hemangioma is referred to as Kasabach- Merritt syndrome.
Platelet Dysfunction Glanzmann's thrombasthenia – autosomal recessive disorder caused by congenital deficiency in the platelet membrane glycoproteins IIb and IIIa. Bernard-Soulier disease – autosomal recessive disorder caused by a congenital deficiency in platelet membrane glycoprotein Ib
Vascular Factors Congenital Causes – Hereditary hemorrhagic telangiectasia autosomal dominant disorder development of fragile telangiectasia of the skin and mucous membranes – Ehlers-Danlos syndrome characterized by skin hyperelasticity, joint hypermobility and fragility of the skin and blood vessels
Vascular Factors Acquired Causes Henoch-Schönlein purpura – IgA-mediated systemic vasculitis of small blood vessels – nonthrombocytopenic purpura, abdominal pain, arthritis and nephritis – the most common form of vasculitis in children – history of a preceding URTI – Characteristically palpable, gravity dependant purpura
Vascular Factors Acquired Causes Meningococcemia and rickettsial diseases may cause direct damage to blood vessels, with resultant purpura. Child abuse
History Age of Onset Birth Intrauterine infection, maternal idiopathic thrombocytopenic purpura, maternal systemic lupus erythematosus, maternal medication, TAR syndrome, congenital amegakaryocytic thrombocytopenia 2 to 4 years Idiopathic thrombocytopenic purpura 4 to 7 years Henoch-Schönlein purpura
History Onset/chronicity Acute onset ITP, HSP, medication, mechanical cause Long duration Abnormality of platelets, coagulopathy
History Pattern of bleeding Mucosal bleeding Thrombocytopenia, von Willebrand's disease Intramuscular and intra-articular bleeding Hemophilia
History Associated symptoms Abdominal pain, blood in stools, joint pain HSP Lethargy, fever, bone pain Leukemia Intermittent fever, muscoskeletal symptoms SLE Lethargy, polyuria, polydipsia, failure to thrive Uremia Purpura, but otherwise healthy ITP
History Past health Antecedent viral infection, especially an upper respiratory tract infection ITP, HSP Drug use Family history Maternal history Social history
Examination Characteristics of purpura Location on lower extremeties Henoch- Schönlein purpura Location on palms and soles Rickettsial infection Palpable purpura Vasculitis
Laboratory Evaluation A thorough history and a careful physical examination are critical first steps in the evaluation of children with purpura.
RED FLAGS Fever, lethargy, weight loss, bone pain, joint pain, pallor, Lymphadenopathy hepatosplenomegaly
Summary Petechiae and purpura result from a wide variety of underlying disorders and may occur at any age red, nonblanching maculopapular lesions caused by intradermal capillary bleeding Classified into platelet or vascular causes Idiopathic thrombocytopenic purpura is the most common cause of thrombocytopenia in children. Henoch-Schönlein purpura is the most common form of vasculitis in children, and the purpuric rash is almost always palpable.