Radioimmunoassay of main urinary metabolite of prostaglandin F2alpha in patients with diffuse interstitial fibrosing pneumonitis (DIFP) and other respiratory diseases.

Radioimmunoassay of 5alpha, 7alpha-dihydroxy-11-keto-tetra-norprosta-1,16-dioic acid, main urinary metabolite of prostaglandin F2alpha (PGF2alpha-MUM), was performed in patients with various respiratory diseases including diffuse interstitial fibrosing pneumonitis (DIFP, fibrosing alveolitis). Twenty-four hr excretion of PGF2alpha-MUM in patients with primary lung cancer, pulmonary fibrosis secondary to collagen diseases and stationary DIFP was normal. On the other hand, 24 hr excretion of PGF2alpha-MUM in patients with carcinomatous pleuritis was high and that in patients with aggravating DIFP was markedly high. There was no correlation between serum LDH levels and 24 hr excretion of PGF2alpha-MUM.