Paroxysmal nocturnal hemoglobinuria (PNH) is a rare blood disease in which red blood cells break apart. The Ham test and flow cytometry are two blood tests used to diagnose PNH.

What Is the Ham Test?

The Ham test checks whether red blood cells become more fragile when they are placed in mild acid.

What Is Flow Cytometry?

Flow cytometry suspends microscopic particles in a stream of fluid. The particles are then passed by an electronic detection apparatus. This tool counts and examines them. It can measure certain proteins associated with PNH to diagnose the disease.

PNH Treatment

We treat some people who have PNH with blood transfusions, folic acid, and if appropriate, iron supplements. If you have low levels of red blood cells, platelets, and white blood cells, we may recommend that you take steroids. Immunosuppressive drugs, such as cyclosporine (Gengraf^®, Neoral^®, Sandimmune^®) and antithymocyte globulin, may also help.

Blood clots are usually treated with anticoagulants. If the clots are severe, a drug called a tissue plasminogen activator can rapidly dissolve them.

PNH can be cured by a stem cell (bone marrow) transplant. This procedure is considered on an individual basis, based on your age and symptoms.