Wessex Branch of the Association of Clinical Pathologists Abstracts of Meeting in Bristol, November 1984

There has been much debate as to whether muscle is present in normal lymph nodes and, if so, where. There are few records of muscle in abnormal lymph nodes. An incidental observation of muscular proliferation (Lott and Davies, this Journal, 1983, 98, 90-91) in an axillary node draining breast carcinoma prompted this further investigation. Examination by dissection microscopy and at higher magnification of inguinal and axillary lymph nodes for 'normal or reactive' (66 nodes) and breastcancer axillary resections (344 nodes) showed that, overall, 8% of these superficial nodes displayed excessive smooth-muscle proliferation in the hilar region. These nodes were further classified as to the degree of smooth-muscle proliferation, and the quantity of blood vessels in their hila. A statistically significant relationship (P = 0.01) between these last two features was found. Additionally, a tendency was found for nodes (in cases where several were resected) to be involved simultaneously to the same degree. In the series the highest frequency of such changes was found in the inguinal nodes, which are well known to be especially susceptible to postinflammatory fibrosis, from men. In view of these findings, it is postulated that hilar smooth-muscle proliferation in superficial lymph nodes may be a marker of earlier inflammatory reactions, leading to regional lymphadenitis. It seems likely that the smooth muscle cells may be derived from the vessels in the hila of the lymph nodes. It is Possible that smooth-muscle hyperplasia, at least in the circumstances studied, may reflect endogenous chemical stimuli released during inflammation. INFECTIONS OF INDWELLING CENTRAL VENOUS CATHETERS IN A PAEDIATRIC