SUPPURATIVE LESIONS WITHOUT PROMINENT EPITHELIOID CELL RESPONSE IN ABSCESS-FORMING GRANULOMATOUS LYMPHADENITIS

To clarify the clinicopathological significance of the suppurative les ions without no epithelioid granulomatous response (SLs without Ep) in lymph nodes and their relationship to abscess-forming granulomatous l ymphadenitis (AGL) and cat scratch disease (CSD), 10 cases were assess ed clinicopathologically and immunohistologically. SLs without Ee were located in the subcapsular sinus, paracortical area and medullary cor ds, but not in the germinal centers. The microabscesses were surrounde d by collections of monocytoid B-lymphocytes (MBLs), histiocytes witho ut epithelioid features, neutrophils, small lymphocytes and small numb ers of plasma cells. The majority of the MBLs seen in the SLs without Ep were of the large cell type. The histological triad of toxoplasmic lymphadenitis, i.e., reactive follicular hyperplasia, small clusters o f epithelioid cells and aggregates MBLs, were also seen in all cases. Some of the clinical and pathological findings in our 10 cases were ch aracteristic of CSD, i.e., (1) cat exposure before the lymphadenopathy was in four of the 10 cases, (2) occurrence in autumn and winter mont hs in all cases, (3) typical suppurative granulomas surrounded by pali saded epithelioid cells were in four of the 10 cases, and (4) Warthin- Starry silver stain-positive bacteria were detected in seven of the 10 cases. The results of our study suggest that SLs without Ep are an ea rly stage of CSD.