Coagulation disorders: Pathology review


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Coagulation disorders: Pathology review

Hematological system


Iron deficiency anemia



Sideroblastic anemia

Anemia of chronic disease

Lead poisoning

Hemolytic disease of the newborn

Glucose-6-phosphate dehydrogenase (G6PD) deficiency

Autoimmune hemolytic anemia

Pyruvate kinase deficiency

Paroxysmal nocturnal hemoglobinuria

Sickle cell disease (NORD)

Hereditary spherocytosis

Anemia of chronic disease

Aplastic anemia

Fanconi anemia

Megaloblastic anemia

Folate (Vitamin B9) deficiency

Vitamin B12 deficiency

Fanconi anemia

Diamond-Blackfan anemia

Heme synthesis disorders

Acute intermittent porphyria

Porphyria cutanea tarda

Lead poisoning

Coagulation disorders


Vitamin K deficiency

Platelet disorders

Bernard-Soulier syndrome

Glanzmann's thrombasthenia

Hemolytic-uremic syndrome

Immune thrombocytopenic purpura

Thrombotic thrombocytopenic purpura

Mixed platelet and coagulation disorders

Von Willebrand disease

Disseminated intravascular coagulation

Heparin-induced thrombocytopenia

Thrombosis syndromes (hypercoagulability)

Antithrombin III deficiency

Factor V Leiden

Protein C deficiency

Protein S deficiency

Antiphospholipid syndrome


Hodgkin lymphoma

Non-Hodgkin lymphoma


Chronic leukemia

Acute leukemia

Leukemoid reaction

Leukemoid reaction

Dysplastic and proliferative disorders

Myelodysplastic syndromes

Polycythemia vera (NORD)

Myelofibrosis (NORD)

Essential thrombocythemia (NORD)

Langerhans cell histiocytosis

Mastocytosis (NORD)

Plasma cell dyscrasias

Multiple myeloma

Monoclonal gammopathy of undetermined significance

Waldenstrom macroglobulinemia

Hematological system pathology review

Microcytic anemia: Pathology review

Non-hemolytic normocytic anemia: Pathology review

Intrinsic hemolytic normocytic anemia: Pathology review

Extrinsic hemolytic normocytic anemia: Pathology review

Macrocytic anemia: Pathology review

Heme synthesis disorders: Pathology review

Coagulation disorders: Pathology review

Platelet disorders: Pathology review

Mixed platelet and coagulation disorders: Pathology review

Thrombosis syndromes (hypercoagulability): Pathology review

Lymphomas: Pathology review

Leukemias: Pathology review

Plasma cell disorders: Pathology review

Myeloproliferative disorders: Pathology review


Coagulation disorders: Pathology review

USMLE® Step 1 questions

0 / 3 complete


USMLE® Step 1 style questions USMLE

of complete

A 3-week-old boy presents to the emergency department due to worsening vomiting at home. The vomiting began suddenly today, and the patient has been more sleepy than usual. He was born full-term at home to a mother who has a history of epilepsy but is otherwise healthy. The patient has not received any vaccines since the mother is concerned they will increase his risk of developing “behavioral disorders.” Temperature is 37.0°C (98.6°F), pulse is 190/min, respirations are 52/min, and blood pressure is 104/54 mmHg. On physical examination the infant begins seizing with tonic-clonic movements in the upper and lower extremities. He is noted to have a bulging anterior fontanelle and downward displacement of the eyes. No pain is elicited with flexion of the neck. Point of care glucose is 60 mg/dL. Which of the following best describes the etiology of this patient’s clinical presentation?

Memory Anchors and Partner Content


Content Reviewers

Yifan Xiao, MD

Antonia Syrnioti, MD


Robyn Hughes, MScBMC

Maria Emfietzoglou, MD

Kaylee Neff

Salma Ladhani, MD

At the hematology ward, there’s Braden, a 5 year old male, who developed prolonged bleeding after circumcision.

His mother is worried because he has a history of recurrent hemarthrosis after minor falls.

Family history reveals a relative of his mother who suffered from bleeding diathesis.

Now, there’s also a 3 day old preterm baby, called Harlow, who is bleeding severely from the umbilicus.

Her mother states that she did not get the standard care after delivery. CBC, PT and PTT are ordered for both patients.

They both have normal platelet count.

Now, Braden has normal PT but elevated PTT, while Harlow has both PT and PTT elevated.

Both Braden and Harlow are suffering from a hemostasis disorder.

Hemostasis disorders, also known as bleeding disorders, can be broadly divided into three groups.

The first includes problems with primary hemostasis, which is the formation of the platelet plug, so they are also called platelet disorders.

The second group includes problems with secondary hemostasis, which is making a strong fibrin clot through activation of the intrinsic, extrinsic and common coagulation pathways, and so they’re known as coagulation disorders.

And the last group includes disorders that affect both primary and secondary hemostasis and are known as mixed platelet and coagulation disorders.

Let’s focus on coagulation disorders that are usually due to a decrease in the number of clotting factors and causes include hemophilia and vitamin K deficiency.

So, let’s look at hemophilia first.

They are a group of inherited bleeding disorders caused by deficiencies in various coagulation factors.

Hemophilia A and B are X-linked recessive disorders so a high yield fact is that they almost exclusively affect males while females are carriers.


  1. "Robbins Basic Pathology" Elsevier (2017)
  2. "Harrison's Principles of Internal Medicine, Twentieth Edition (Vol.1 & Vol.2)" McGraw-Hill Education / Medical (2018)
  3. "Kumar & Clark's Clinical Medicine" Saunders (2009)
  4. "Establishing the Prevalence and Prevalence at Birth of Hemophilia in Males" Annals of Internal Medicine (2019)
  5. "The Diagnosis and Management of Congenital Hemophilia" Seminars in Thrombosis and Hemostasis (2012)
  6. "Haematology" Scion Pub Limited (2010)
  7. "Vitamin K-dependent carboxylase. Haematologia (Budap)" Vermeer C, De boer-van den berg MA. (1985)

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