Ischemic priapism of hematological origin

Specialty: Hematology.

• Low hematological flow priapism
• prolonged painful non-sexual erection
• venous stasis of the corpus cavernosum

Why it occurs

• Sickle cell anemia / Sickle cell disease (common in homozygous HbSS patients; deoxygenation induces the polymerization of hemoglobin S, deforming the erythrocytes into a sickle shape, which mechanically obstruct the outflow venules of the corpora cavernosa, trapping blood and causing acidosis and local ischemia)
• Acute or chronic myeloid leukemia with extreme hyperleucytosis (leukostasis of the corpora cavernosa due to the physical accumulation of blasts or large immature granulocytes that block venous drainage)
• Multiple myeloma (secondary to marked plasma hyperviscosity or associated cryoglobulinemia that slows venous flow)
• Essential thrombocythemia (platelet microthrombosis of the helicine veins or cavernous sinuses)
• Treatment with pro-erectile drugs or supratherapeutic anticoagulants.

Initial workup

Corporal cavernous blood gas (direct aspiration of blood from the corpus cavernosum using a fine needle; it will reveal deep acidosis with pH <7.25, pO2 <30 mmHg and pCO2 >60 mmHg in the ischemic variant, differentiating it from non-ischemic or high-flow priapism); immediate complete blood count with differential count (to evaluate extreme leukocytosis or profound sickle cell anemia); peripheral blood smear (search for sickle cells, Howell-Jolly bodies, or circulating blasts); hemoglobin electrophoresis (to confirm HbSS phenotype or sickle cell variants); Color Doppler ultrasound of the penis and perineum (will demonstrate the absence of blood flow in the cavernous arteries during the ischemic episode).

Standard management

• Etilephrine / Phenylephrine — alpha-adrenergic agonists for direct intracavernosal injection; They cause vasoconstriction of the afferent arteries and contraction of the trabecular smooth muscle, facilitating venous drainage; requires close monitoring of blood pressure and heart rate during the procedure
• Hydroxyurea / Hydroxycarbamide — for chronic prophylactic use in sickle cell disease; increases the production of fetal hemoglobin HbF, drastically reducing the frequency of vaso-occlusive crises and priapism
• Ruxolitinib or other chemotherapeutic induction agents such as Cytarabine — for the rapid reduction of tumor mass in cases of leukemias with hyperleucytosis
• Vigorous intravenous crystalloid solutions for rehydration and supplemental oxygen (mandatory initial supportive therapy).