Low serum haptoglobin in hemolysis is masked by -
Haptoglobin is an acute phase protein and its level increased in case of any inflammation. In hemolytic anemias there is fall in serum haptoglobin levels. If there is any inflammation along with it there will be rise in haptoglobin levels as it is an a/c phase protein (eg biliary obstruction causes inflammation) Ref:Postgraduate Hematology by Victor Hoffbrand pg 127 Ref Robbins 9/e pg 419
Pregnancy
Liver disease
Bile duct obstruction
Malnutriotion
Haematology