Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (393 page)

   Δ-storage pool diseases are characterized by the absence of dense bodies. In most cases, the second wave aggregation with ADP and epinephrine is absent. There are several subtypes:

   Δ-storage pool disease without other associations: autosomal dominant.

   Hermansky-Pudlak syndrome: autosomal recessive inheritance due to deficiency of dense bodies. It is associated with oculocutaneous albinism. Hermansky-Pudlak syndrome has a high prevalence in northwest Puerto Rico and is the most common cause of oculocutaneous albinism in Japan.

   Chédiak-Higashi syndrome: autosomal recessive deficiency of dense bodies; associated with oculocutaneous albinism. Giant cytoplasmic granules are present in neutrophils, monocytes, and lymphocytes.

   Thrombocytopenia-absent radius syndrome: autosomal recessive. It is associated with hypomegakaryocytic thrombocytopenia.

   Wiskott-Aldrich syndrome: X-linked recessive condition due to deficiencies of dense bodies and cytoskeletal regulation. It is associated with thrombocytopenia with small platelets, eczema, and T-cell immune deficiency.

   May-Hegglin anomaly is an autosomal dominant abnormality of granulocytes and platelets, associated with thrombocytopenia, giant platelets, Döhle-like bodies in neutrophils, and chronic renal disease.

   Signal transduction defects due to abnormal platelets receptors. It is uncertain to what extent single receptor defects result in clinical bleeding.

   Integrin α2β1 and GPVI (collagen receptor defects)

   P2Y12 (ADP receptor) defect

   Epinephrine receptor defect

   Thromboxane A
₂
receptor deficiency

   Signal transduction defects due to abnormalities in arachidonic acid pathways and thromboxane A
₂
synthesis.