Immunohistochemical study of CA 19-9 and SPan-1 in cases of hydronephrosis.

Although the serum level of carbohydrate antigen (CA) 19-9 is reportedly increased in patients with hydronephrosis, virtually no immunohistochemical studies of this condition have been performed. Therefore, we examined immunohistochemically 11 hydronephrotic kidneys and 3 normal control kidneys using antibodies against CA 19-9 and SPan-1, another sialylated carbohydrate antigen. Immunoreactivity for CA 19-9 was seen in the transitional and tubular epithelia in most of the hydronephrotic kidneys (9 of the 11 cases), and also detected in 2 of the 3 control specimens, although there the distribution appeared to be limited. SPan-1 immunoreactivity showed the same trend. CA 19-9 and SPan-1 immunoreactivity in hydronephrosis appeared to be more widely distributed than in controls, although its mechanism remains unclear.