Bosentan-induced immune hemolytic anemia in 17 years old man. A case report

Hemolytic anemia is a very important immune-mediated reaction, which its late diagnosis can be fatal. Medications along with other causes can induce hemolytic anemia. Drug induced immune hemolytic anemia (DIIHA) is caused by the development of autoantibodies. Accordingly, DIIHA is rare and there is not enough data for its prevalence. Number of drugs that can cause DIIHA have increased in recent decades. A 17-year-old man who had congenital single ventricle heart (CHB) and pulmonary artery hypertension (PAH) was admitted at Imam Khomeini hospital complex affiliated to Tehran University of Medical Sciences, with chief complaint of jaundice and icter. Bosentan and Tadalafil were in the list of the drugs used by this patient. Although both drugs were recommended to be discontinued in the patient, in the course of hospitalization, the patient accidentally continued to take his Tadalafil. However, the patient's recovery continued. Given that the patient's Coombs test was positive, his hemolytic anemia mechanism was drug-induced immune-mediated hemolytic anemia. As a result, according to Naranjo score = 6, Bosentan was considered as the main possible culprit to induce DIIHA in this patient. Following the discontinuation of Bosentan and receiving Prednisolone, the patient's clinical symptoms and laboratory parameters resolved and the patient was then discharged.