Diagnostic importance of the nucleolar organizer regions in Wegener's granulomatosis.

The number and distribution pattern of silver staining nucleolar organizer regions (AgNORs) were thought to reflect the cellular proliferative activity and the malignancy of tumours. Using a silver-staining method, the variations of AgNORs have been studied in patients with atypical inflammatory lesion (n = 5), malignant reticulosis (n = 5) and Wegener's granulomatosis (n = 6). Our results reveal that there was a statistically significant difference (p < 0.01), highly suggestive of a difference in AgNOR counts between the atypical inflammatory lesion and Wegener's granulomatosis, with the Wegener's granulomatosis specimens having the higher irregular AgNORs, but the difference between Wegener's granulomatosis and malignant reticulosis is probably not clinically important. It is concluded that AgNORs may be useful in differentiating Wegener's granulomatosis from an atypical inflammatory lesion, and the simplified counting technique is adequate for the purpose.