Platelet storage pool deficiency refers to a group of conditions that are caused by problems with the platelet granules. Platelet granules are tiny storage sacs found within the platelets which release various substances to help stop bleeding. Platelet storage pool deficiencies occur when platelet granules are absent, reduced in number, or unable to empty their contents into the bloodstream. The signs and symptoms include frequent nosebleeds; abnormally heavy or prolonged menstruation ; easy bruising; recurrent anemia ; and abnormal bleeding after surgery, dental work or childbirth. Platelet storage pool deficiencies may be genetic or acquired (non-genetic). They can also be part of an inherited genetic syndrome such as Hermansky-Pudlak syndrome, Chediak-Higashi syndrome, thrombocytopenia-absent radius (TAR) syndrome, and Wiskott-Aldrich syndrome. Treatment is symptomatic. The disease is platelet storage pool deficiency (Monarch Disease Ontology term MONDO_0008495). Also known as: alpha dense granule deficiency, combined alpha-delta platelet storage pool deficiency, dense body defect, platelet dense granule deficiency, platelet storage pool defect.