Patient has hemoglobin in urine on 1st morning voiding but none during day.
Hereditary
Erythroblast Multinuclearity with positive acid-serum
test (HEMPAS):
This is due to tissues becoming more
acidic during the night because of increased CO2 which causes complement to attach to red cells
and patient has red cells which are sensitive to complement. The red cell is destroyed as it circulates
(intravascular hemolysis) and thus free hemoglobin is excreted by kidneys.
Patient has red cells (type II) that
are sensitive to lysis by complement
PNH is positive for sucrose and
acid-serum tests while HEMPAS is only positive for acid-serum test.