4456
The probands serum was incapable of mediating lysis of erythrocytes from a patient with paroxysmal nocturnal hemoglobinuria in both the sucrose hemolysia and acid hemolysis tests , and also lacked bactericidal activity against sensitized or unsensitized Salmonella typhi .
 paroxysmal nocturnal hemoglobinuria
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Disease 
Text: {0} 
Answer:
 paroxysmal nocturnal hemoglobinuria