Liesegang rings in cytologic samples accompanied by calcium oxalate-like crystals. A report of three cases.
The presence of Liesegang rings (LRs) in cytologic specimens is a morphologic curiosity. The exact mechanism of formation and composition of these peculiar rings is a mystery. Their morphologic resemblance to parasites is well recognized and illustrated. Their association with calcium oxalate-like crystals and their presence in a tubercular lymph node are described for the first time below. Giemsa-stained aspiration smears from an enlarged lymph node and two breast lumps showed purple rings of variable morphology resembling ova, larvae or adult parasites. Misdiagnosis of parasites was avoided by careful evaluation. In all three cases the LRs were associated with calcium oxalate-like crystals and were nonbirefringent. LRs can be mistaken for ova, larvae or adult parasites. Awareness of their varied morphology is helpful in avoiding misinterpretation and overdiagnosis of parasitic lesions. The coexistence of LRs and crystals was an unusual finding in this study.