Atypical HUS: Diagnosis of the Disease

Atypical HUS Information for Parents & Patients

There are two steps to diagnosing Atypical HUS. The immediate test, often done in the ER or doctor's office at the first sign of the disease is a blood test. A simple blood test will show shattered red blood cells, (Shistocytes) and low platelet counts, with an elevated LDH. These early tests can show a definite sign of Atypical HUS quite early.

If the above test shows Atypical HUS to be the main suspect, then genetic testing can confirm the root cause, and will also play a role in the Long term plan needed to deal with the disease.


Atypical HUS is an ultra rare disease. The number of cases in the U.S. are unknown, and are believed to be around 300 - 600, but it is not mandatory to report. (Since Atypical HUS is not a communicable disease, reporting on it is not mandatory, but optional).

Adults and Atypical HUS

Atypical HUS is most common with young children. The reason for that is unknown, but some believe that the genetic problem is present, but does not become activated until a virus such as the flu, or a bacterial infection occurs. Adults can get a disease with many of the same symptoms. Sometimes, the adults are diagnosed with Atypical HUS. But more often, the adult version involves different symptoms. So quite often, the adults present themselves with TTP, or thrombotic thrombocytopenic purpura. TTP has a lot of similarities to Atypical HUS, but the symptoms do not show up as kidney failure. Instead, the disease exhibits a lot of Neurological signs. Check out some of our additional TTP sites and other resources.