Liesegang Rings in Renal Cyst Fluid Laurie B.K. Katz, M.D., and Hormoz Ehya, M.D.
Peculiar ring-like structures identifed as Liesegang rings (LRs) were found in renal cyst fluid from three patients with benign renal cysts. They ranged in size from 5 to 820 p. Most had a double-layer outer wall with equally spaced radial crossstriations and an amorphous central nidus. Special stains were performed in one case, and the results are discussed. Reports of LRs in cystic or inflamed tissues have recently appeared in the literature. Some LRs have been mistaken for eggs or mature components of the giant kidney worm, Dioctophyma renale. We propose that cytologic assessment of renal cyst fluid in conjunction with histologic examination decreases the likelihood of misdiagnosis of LRs. Diagn Cytopathol 1990;6:197-200 Key Words: Liesegang bands; Liesegang phenomena; Precipitation phenomena; Dioctophyma renale; Giant kidney worm
Liesegang rings (LRs) are the product of a piecipitation phenomenon that was first described by Raphael E. Liesegang, a German biochemist, who observed the in vitro periodic precipitation of certain chemicals in colloidal gels.’ LRs are also thought to occur in nature, such as LRs of calcium carbonate in oolitic limestone.2 In vivo examples include pulmonary, central nervous system, and prostatic corpora amylacea. Gallstones, renal stones, psammoma bodies, and even the coloration pattern of butterfly wings have all been proposed to result from Recently, reports of LRs in Liesegang-like renal and perirenal cysts and in other cystic or inflamed tissues have appeared in the literat~re.~,~.’ In surgical specimens, LRs have been mistaken for eggs, larvae, or mature components of parasites, in particular, the giant kidney worm, Dioctophyma renale.8-’0 We report the finding of LRs in the cytologic material aspirated from three patients with benign renal cysts.
Case Reports Case 1
A 52-yr-old white female was found to have microscopic hematuria on routine urinalysis. Subsequently, she acReceived December 5, 1988. Accepted April 14, 1989. From the Cytopathology Laboratory, Department of Pathology and Cell Biology, Thomas Jefferson University Hospital, Philadelphia, PA. Address reprint requests to Laurie Katz, M.D., Department of Pathology, Thomas Jefferson University, 11th and Walnut St, Rm 405-PAV, Philadelphia, PA 19107. 0
1990 WILEY-LISS, INC
knowledged having occasional urgency and bilateral midback discomfort. Intravenous pyelogram revealed an enlarged right kidney that was presumed secondary to renal cysts. Computed tomography demonstrated a hyperdense lesion in the left kidney, posteriorly. Ultrasound showed multiple bilateral simple cysts and no evidence of a solid mass. Magnetic resonance imaging also showed bilateral renal cysts with a complex cyst on the posterior aspect of the left kidney. A nuclear renal scan confirmed the presence of bilateral cysts and demonstrated a decreased glomerular filtration rate. The patient’s past medical history included childhood rheumatic heart disease and eclampsia of pregnancy. She was taking no medications. The family history was negative for renal disease. Except for obesity, physical examination was unremarkable. Other laboratory and radiologic studies were noncontributory. In order to rule out malignancy, the patient was explored through a left flank incision. Multiple hemorrhagic cysts of varying size were found studding the renal surface. Cysts thought to represent the complex lesions seen in preoperative scanning were aspirated, and 5 ml of thick brown fluid was obtained. Multiple biopsies were taken, and the remaining cyst walls were fulgurated. The patient’s postoperative course was uneventful. Case 2 A 6 1-yr-old white female complained of right-upper-
quadrant pain and nausea. Abdominal ultrasound and computed tomography were performed during the course of her evaluation, and a complex left renal mass was found. Arteriogram showed a hypovascular area in the left kidney. She denied left-sided abdominal pain, hematuria, and other urinary symptoms. The patient’s past medical history included appendectomy, varicose vein ligation, and vaginal hysterectomy with bilateral oophorectomy and bladder repair. She was taking no medications. Physical examination was unremarkable. Other laboratory and radiologic studies were noncontributory. In order to rule out malignancy, a left renal exploration was performed. A 2-cm cystic mass was found on the anterior portion of the left kidney. Three milliliters of cyst fluid was aspirated with a 20-gauge needle and sent to Diagnostic Cytopathology, Vol6, N o 3
197
KATZ AND EHYA
cytology. Frozen-section biopsies of the cyst wall and the edge of the cyst were interpreted as being a benign renal cyst. The patient’s postoperative course was uneventful.
Case 3 A 79-yr-old woman was found to have a 2-cm hypciechoic mass in the mid to lower pole of the left kidney during the course of evaluation for colorectal cancer. The lesilon was cystic in nature but did not fulfill the sonographic criteria for a simple cyst. Although it was felt most likely to represent a simple renal cyst with debris and/or hemorrhage, the possibility of a cystic renal tumor could not be entirely excluded. The patient denied having urinary symptoms with the exception of some frequency. Past medical history included right mastectomy for mammary carcinoma and total abdominal hysterectomy. Following colectomy, the patient underwent aspiration of the renal cyst under ultrasonic guidance and 35 ml of bloody fluid was obtained. The patient tolerated the proceduire well without complications.
Fig. 1. Cell block. Numerous Liesegang rings of varying size are present (H&E, x400).
Materials and Methods Aspirated fluid was mixed with an equal volume of a 50% ethanol solution and sent to the cytology laboratory. In all cases, two slides were made by membrane filtration. In case 1, two slides were also made by direct smearing of the sediment of the centrifuged specimen. The slides were subsequently fixed in 95% ethanol and stained by the Papanicolaou technique. Additionally, a cell block was prepared in cases 1 and 3; after formalin fixation and paraffin embedding, 4-mm sections were made and stained with hematoxylin-eosin (H&E). The biopsy material from cases 1 and 2 was fixed in 10% buffered formalin, and paraffin-embedded sections were stained with H&E. Additional sections of the cell block and tissue were stained with Alizarin red, von Kossa, Prussian blue, and periodic acid-Schiff (PAS) in case 1 only.
were identified in the smear preparations, staining an aqua-green with the Papanicolaou stain, clarity and detail of structure were best appreciated in the filters. The biopsy specimens from case 1 consisted of several irregularly shaped fragments of membranous tissue. Light microscopy revealed benign cysts lined by a single layer of flat epithelial cells. Numerous calcifications could be identified within the cyst walls and within cystic spaces. Most of the specimens also showed a mild inflammatory infiltrate. Lying free within cystic spaces, occasional LRs
Results Examination of the filter preparations from all three cases revealed numerous ring-like structures ranging in size from 5 to 820 p (Fig. 1). The rings were predominantly spherical in shape, although some elongated and irregularly shaped structures were seen (Fig. 2). Most had an accentuated, double-layer outer ring containing equally spaced radial cross-striations. An amorphous central nidus was also present (Fig. 3). These structures were interpreted as Liesegang rings. In addition, scattered macrophages and rare inflammatory cells were seen in the aspirated fluid (Fig. 4). LRs were also identified in cell block preparations. In case 1, they stained with eosin, appearing pink. In case 3, the rings had a brownish hue. Birefringence could not be demonstrated. While LRs 198
Diagnostic Cytopathology, Vol6, No 3
Fig. 2. Cell block. An irregular-shaped Liesegang ring is shown surrounded by numerous smaller spherical to oval-shaped rings (H&E, x400).
LIESEGANG RINGS IN RENAL CYST FLUID
been reported else~here.~~"-'* It should be emphasized, however, that concentric bands are not observed every time that an outer electrolyte is allowed to diffuse into a gelled solution of an inner electrolyte. The formation of periodic bands appears to depend on the concentration of the reactants, the presence of impurities, and the pH and composition of the gel medium. An acceptable explanation of the phenomenon must consider all these factors. The process of LR formation in vivo is likely to be even more complex, resulting from the interaction of organic as well as inorganic substances2In case 1, stains for calcium and mucopolysaccharides were weakly positive. However, in three cases reported by Sneige et a 1 . y staining of LRs for iron, calcium, mucopolysaccharides, amyloid, protein, keratin, and hemoglobin was all negative. On the other hand, in the series of Tuur et a1.,2 LRs from the pericardium of one patient revealed the presence of both calcium and iron, and LRs in three other cases demonstrated calcium; also, energy-dispersive x-ray analysis showed silicon, sulfur, and calcium to be present in LRs from a patient with renal cysts. It is of interest that in the literature to date, the formation of LRs (other than the common corpora Fig. 3. Filter preparation. Liesegang structures demonstrating a doublelayer outer ring in which equally spaced radial cross-striations are clearly visible (Papanicolaou stain, x 1,000).
were seen (Fig. 5). They ranged in size from 5 to 55 p, and their shapes were similar to those seen in the cytologic material. Again, the structures were not birefringent. The biopsy specimen from case 2 consisted of two irregularly shaped pieces of membranous, red-tan tissue. Light microscopy showed a thick fibrous cyst wall with mild inflammation, focal hemosiderin deposition, and focal calcification. Adjacent renal tissue was unremarkable. LRs were not identified. The LRs in the cell block of case 1 were negative for calcium by the Alizarin red and von Kossa methods, whereas in tissue there was weak staining of the outer rings of some of the LRs by Alizarin red. The Prussian blue stain for iron was uniformly negative. In approximately 50% of the rings in the cell block, the amorphous central material showed weak staining with PAS. However, no reaction with PAS was noted in tissue sections.
Discussion The Liesegang phenomenon is easily demonstrated in vitro by allowing one reactant, for example, potassium chromate, to dissolve in agar solution and to gel in a test tube. A second reactant, such as silver nitrate, is then layered over the gel. As the silver nitrate solution diffuses into the gel, silver chromate will precipitate in the form of a series Of concentric rings separated by Of gel.' Physicochemical explanations for LRs in vitro have
Fig. 4. Filter preparation. These Liesegang rings are shown to be smaller than an adjacent macrophage (Papanicolaou stain, x 1,000). Diagnostic Cytopathology.Vol6, N o 3
199
KATZ AND EHYA
of LRs is unlikely to occur. There is significantly greater clarity of detail of the LR structures in cytologic preparations than in paraffin-embedded sections, perhaps due to the lack of artifacts produced in histologic processing of the tissue. In particular, our filter preparations clearly demonstrated varying-sized, smooth-walled, laminated rings with peripheral cross-striations and an amorphous center. Many of the rings were smaller in size than adjacent macrophages and were thus readily recognized as being below the appropriate size range for eggs of D. renale (Fig. 4). We conclude that, while LRs may be mistaken for the giant kidney worm, D. renale, in histologic specimens by pathologists unfamiliar with the LR phenomenon, the possibility of misdiagnosis is less likely when concomitant cytologic evaluation of renal cyst fluid is made.
References
Fig. 5. Tissue section from renal cyst showing Liesegang rings lying free within cystic spaces (H&E, x400).
amylacea), has been limited to cystic sites and inflamed, fibrotic, or necrotic tissues. Tuur et al. proposed that the high-molecular-weight polymers that are found in cystic and inflamed tissue may produce a colloidal extracellular environment similar to that of the colloidal gels in which LRs are formed in vitro.* Furthermore, they hypothesized that impurities such as foreign bodies and microorganisms may act as nidi for the formation of LRs in vivo. LRs in paraffin-embedded tissues have been misdiagnosed as eggs, larvae, and adult components of the giant kidney worm, D. renale.*-" The constancy of size of D. renale eggs (60-80 x 39-47 p) and their periipheral scalloped pattern should help to distinguish them from LRs, which vary greatly in size and have a smooth outer ring. The adult D. renale worm measures 4-12 mm in diameter, whereas LRs greater than 1 mm have not been described. Therefore LRs should not be mistak.en for cross-sections of adult worms. Since entire structures rather than cross-sections are examined in cytologic preparations, the misidentification
200
Diagnostic Cytopathology, Vol6,No 3
1. Liesegang RE. Uber einige eigenschaften von gallerten. Naturwissenschaften 1896;11:353-62. 2. Tuur SM, Nelson AM, Gibson DW, et al. Liesegang rings in tissue. How to distinguish liesegang rings from the giant kidney worm, Dioctophyma renale. Am J Surg Pathol 1987;11:598-605. 3. Baar HS, Ferguson FF. Microlithiasis alveolaris pulmonum. Arch Pathol 1963;76:659-66. 4. Gortner RA. Outlines of biochemistry. The organic chemistry and physiochemical reactions of biologically important compounds and systems. 2nd ed. New York: Wiley, 1938;312-6. 5. Spencer H. Pulmonary corpora amylacea. In: Spencer H, ed. Pathology of the lung. 4th ed. New York: Pergamon, 1985;739-40. 6. Sneige N, Dekmezian RH, Silva EG, Cartwright J Jr, Ayala AG. Pseudoparasitic liesegang structures in perirenal hemorrhagic cysts. Am J Clin Pathol 1988;89:148-53. 7. Sneige N, Dekmezian R, Zaatari GS. Liesegang-like rings in fine needle aspirates of renal/perirenal hemorrhagic cysts. Acta Cytol 1988;32:547-51. 8. Fernando SSE. The giant kidney worm (Diociophyma renale) infection in man in Australia. Am J Surg Pathol 1983;7:281-4. 9. Sun T. The worm turns. Am J Surg Pathol 1987;11:651. 10. Sun T, Turnbull A, Lieberman PH, Sternberg SS. Giant kidney worm (Dioctophyma renale) infection mimicking retroperitoneal neoplasm. Am J Surg Pathol 1986;10:508-12. 11. Vold PD, Vold MJ. Colloid and interface chemistry. London: Addison-Wesley, 1983545-50. 12. Bradford SC. Adsorptive stratification in gels. Biochem J 1916;lO: 169-75. 13. Bradford SC. Adsorptive stratification in gels 11. Biochem J 1917;11:14-20. 14. Davies ECH. Liesegang rings 111. The effect of hydrogen ion concentration on the formation of colloidal gold in silicic acid gel. Rhythmic bands of purple of cassius. J Am Chem Soc 1923;45:2261-8. 15. Hedges ES. Liesegang rings and other periodic structures. London: Chapman & Hall, 1932:l-22. 16. Kirkaldy JS. A continuum theory of liesegang phenomena. Scrip Metal 1986;20:1571-4. 17. Stern KH. The liesegang phenomenon. Chem Rev 1954;57:79-99. 18. Venzl G. Postnucleation theory of liesegang bands. J Chem Phys 1986;85:2006-11.
Peculiar ring-like structures identifed as Liesegang rings (LRs) were found in renal cyst fluid from three patients with benign renal cysts. They ranged in size from 5 to 820 p. Most had a double-layer outer wall with equally spaced radial crossstriations and an amorphous central nidus. Special stains were performed in one case, and the results are discussed. Reports of LRs in cystic or inflamed tissues have recently appeared in the literature. Some LRs have been mistaken for eggs or mature components of the giant kidney worm, Dioctophyma renale. We propose that cytologic assessment of renal cyst fluid in conjunction with histologic examination decreases the likelihood of misdiagnosis of LRs. Diagn Cytopathol 1990;6:197-200 Key Words: Liesegang bands; Liesegang phenomena; Precipitation phenomena; Dioctophyma renale; Giant kidney worm
Liesegang rings (LRs) are the product of a piecipitation phenomenon that was first described by Raphael E. Liesegang, a German biochemist, who observed the in vitro periodic precipitation of certain chemicals in colloidal gels.’ LRs are also thought to occur in nature, such as LRs of calcium carbonate in oolitic limestone.2 In vivo examples include pulmonary, central nervous system, and prostatic corpora amylacea. Gallstones, renal stones, psammoma bodies, and even the coloration pattern of butterfly wings have all been proposed to result from Recently, reports of LRs in Liesegang-like renal and perirenal cysts and in other cystic or inflamed tissues have appeared in the literat~re.~,~.’ In surgical specimens, LRs have been mistaken for eggs, larvae, or mature components of parasites, in particular, the giant kidney worm, Dioctophyma renale.8-’0 We report the finding of LRs in the cytologic material aspirated from three patients with benign renal cysts.
Case Reports Case 1
A 52-yr-old white female was found to have microscopic hematuria on routine urinalysis. Subsequently, she acReceived December 5, 1988. Accepted April 14, 1989. From the Cytopathology Laboratory, Department of Pathology and Cell Biology, Thomas Jefferson University Hospital, Philadelphia, PA. Address reprint requests to Laurie Katz, M.D., Department of Pathology, Thomas Jefferson University, 11th and Walnut St, Rm 405-PAV, Philadelphia, PA 19107. 0
1990 WILEY-LISS, INC
knowledged having occasional urgency and bilateral midback discomfort. Intravenous pyelogram revealed an enlarged right kidney that was presumed secondary to renal cysts. Computed tomography demonstrated a hyperdense lesion in the left kidney, posteriorly. Ultrasound showed multiple bilateral simple cysts and no evidence of a solid mass. Magnetic resonance imaging also showed bilateral renal cysts with a complex cyst on the posterior aspect of the left kidney. A nuclear renal scan confirmed the presence of bilateral cysts and demonstrated a decreased glomerular filtration rate. The patient’s past medical history included childhood rheumatic heart disease and eclampsia of pregnancy. She was taking no medications. The family history was negative for renal disease. Except for obesity, physical examination was unremarkable. Other laboratory and radiologic studies were noncontributory. In order to rule out malignancy, the patient was explored through a left flank incision. Multiple hemorrhagic cysts of varying size were found studding the renal surface. Cysts thought to represent the complex lesions seen in preoperative scanning were aspirated, and 5 ml of thick brown fluid was obtained. Multiple biopsies were taken, and the remaining cyst walls were fulgurated. The patient’s postoperative course was uneventful. Case 2 A 6 1-yr-old white female complained of right-upper-
quadrant pain and nausea. Abdominal ultrasound and computed tomography were performed during the course of her evaluation, and a complex left renal mass was found. Arteriogram showed a hypovascular area in the left kidney. She denied left-sided abdominal pain, hematuria, and other urinary symptoms. The patient’s past medical history included appendectomy, varicose vein ligation, and vaginal hysterectomy with bilateral oophorectomy and bladder repair. She was taking no medications. Physical examination was unremarkable. Other laboratory and radiologic studies were noncontributory. In order to rule out malignancy, a left renal exploration was performed. A 2-cm cystic mass was found on the anterior portion of the left kidney. Three milliliters of cyst fluid was aspirated with a 20-gauge needle and sent to Diagnostic Cytopathology, Vol6, N o 3
197
KATZ AND EHYA
cytology. Frozen-section biopsies of the cyst wall and the edge of the cyst were interpreted as being a benign renal cyst. The patient’s postoperative course was uneventful.
Case 3 A 79-yr-old woman was found to have a 2-cm hypciechoic mass in the mid to lower pole of the left kidney during the course of evaluation for colorectal cancer. The lesilon was cystic in nature but did not fulfill the sonographic criteria for a simple cyst. Although it was felt most likely to represent a simple renal cyst with debris and/or hemorrhage, the possibility of a cystic renal tumor could not be entirely excluded. The patient denied having urinary symptoms with the exception of some frequency. Past medical history included right mastectomy for mammary carcinoma and total abdominal hysterectomy. Following colectomy, the patient underwent aspiration of the renal cyst under ultrasonic guidance and 35 ml of bloody fluid was obtained. The patient tolerated the proceduire well without complications.
Fig. 1. Cell block. Numerous Liesegang rings of varying size are present (H&E, x400).
Materials and Methods Aspirated fluid was mixed with an equal volume of a 50% ethanol solution and sent to the cytology laboratory. In all cases, two slides were made by membrane filtration. In case 1, two slides were also made by direct smearing of the sediment of the centrifuged specimen. The slides were subsequently fixed in 95% ethanol and stained by the Papanicolaou technique. Additionally, a cell block was prepared in cases 1 and 3; after formalin fixation and paraffin embedding, 4-mm sections were made and stained with hematoxylin-eosin (H&E). The biopsy material from cases 1 and 2 was fixed in 10% buffered formalin, and paraffin-embedded sections were stained with H&E. Additional sections of the cell block and tissue were stained with Alizarin red, von Kossa, Prussian blue, and periodic acid-Schiff (PAS) in case 1 only.
were identified in the smear preparations, staining an aqua-green with the Papanicolaou stain, clarity and detail of structure were best appreciated in the filters. The biopsy specimens from case 1 consisted of several irregularly shaped fragments of membranous tissue. Light microscopy revealed benign cysts lined by a single layer of flat epithelial cells. Numerous calcifications could be identified within the cyst walls and within cystic spaces. Most of the specimens also showed a mild inflammatory infiltrate. Lying free within cystic spaces, occasional LRs
Results Examination of the filter preparations from all three cases revealed numerous ring-like structures ranging in size from 5 to 820 p (Fig. 1). The rings were predominantly spherical in shape, although some elongated and irregularly shaped structures were seen (Fig. 2). Most had an accentuated, double-layer outer ring containing equally spaced radial cross-striations. An amorphous central nidus was also present (Fig. 3). These structures were interpreted as Liesegang rings. In addition, scattered macrophages and rare inflammatory cells were seen in the aspirated fluid (Fig. 4). LRs were also identified in cell block preparations. In case 1, they stained with eosin, appearing pink. In case 3, the rings had a brownish hue. Birefringence could not be demonstrated. While LRs 198
Diagnostic Cytopathology, Vol6, No 3
Fig. 2. Cell block. An irregular-shaped Liesegang ring is shown surrounded by numerous smaller spherical to oval-shaped rings (H&E, x400).
LIESEGANG RINGS IN RENAL CYST FLUID
been reported else~here.~~"-'* It should be emphasized, however, that concentric bands are not observed every time that an outer electrolyte is allowed to diffuse into a gelled solution of an inner electrolyte. The formation of periodic bands appears to depend on the concentration of the reactants, the presence of impurities, and the pH and composition of the gel medium. An acceptable explanation of the phenomenon must consider all these factors. The process of LR formation in vivo is likely to be even more complex, resulting from the interaction of organic as well as inorganic substances2In case 1, stains for calcium and mucopolysaccharides were weakly positive. However, in three cases reported by Sneige et a 1 . y staining of LRs for iron, calcium, mucopolysaccharides, amyloid, protein, keratin, and hemoglobin was all negative. On the other hand, in the series of Tuur et a1.,2 LRs from the pericardium of one patient revealed the presence of both calcium and iron, and LRs in three other cases demonstrated calcium; also, energy-dispersive x-ray analysis showed silicon, sulfur, and calcium to be present in LRs from a patient with renal cysts. It is of interest that in the literature to date, the formation of LRs (other than the common corpora Fig. 3. Filter preparation. Liesegang structures demonstrating a doublelayer outer ring in which equally spaced radial cross-striations are clearly visible (Papanicolaou stain, x 1,000).
were seen (Fig. 5). They ranged in size from 5 to 55 p, and their shapes were similar to those seen in the cytologic material. Again, the structures were not birefringent. The biopsy specimen from case 2 consisted of two irregularly shaped pieces of membranous, red-tan tissue. Light microscopy showed a thick fibrous cyst wall with mild inflammation, focal hemosiderin deposition, and focal calcification. Adjacent renal tissue was unremarkable. LRs were not identified. The LRs in the cell block of case 1 were negative for calcium by the Alizarin red and von Kossa methods, whereas in tissue there was weak staining of the outer rings of some of the LRs by Alizarin red. The Prussian blue stain for iron was uniformly negative. In approximately 50% of the rings in the cell block, the amorphous central material showed weak staining with PAS. However, no reaction with PAS was noted in tissue sections.
Discussion The Liesegang phenomenon is easily demonstrated in vitro by allowing one reactant, for example, potassium chromate, to dissolve in agar solution and to gel in a test tube. A second reactant, such as silver nitrate, is then layered over the gel. As the silver nitrate solution diffuses into the gel, silver chromate will precipitate in the form of a series Of concentric rings separated by Of gel.' Physicochemical explanations for LRs in vitro have
Fig. 4. Filter preparation. These Liesegang rings are shown to be smaller than an adjacent macrophage (Papanicolaou stain, x 1,000). Diagnostic Cytopathology.Vol6, N o 3
199
KATZ AND EHYA
of LRs is unlikely to occur. There is significantly greater clarity of detail of the LR structures in cytologic preparations than in paraffin-embedded sections, perhaps due to the lack of artifacts produced in histologic processing of the tissue. In particular, our filter preparations clearly demonstrated varying-sized, smooth-walled, laminated rings with peripheral cross-striations and an amorphous center. Many of the rings were smaller in size than adjacent macrophages and were thus readily recognized as being below the appropriate size range for eggs of D. renale (Fig. 4). We conclude that, while LRs may be mistaken for the giant kidney worm, D. renale, in histologic specimens by pathologists unfamiliar with the LR phenomenon, the possibility of misdiagnosis is less likely when concomitant cytologic evaluation of renal cyst fluid is made.
References
Fig. 5. Tissue section from renal cyst showing Liesegang rings lying free within cystic spaces (H&E, x400).
amylacea), has been limited to cystic sites and inflamed, fibrotic, or necrotic tissues. Tuur et al. proposed that the high-molecular-weight polymers that are found in cystic and inflamed tissue may produce a colloidal extracellular environment similar to that of the colloidal gels in which LRs are formed in vitro.* Furthermore, they hypothesized that impurities such as foreign bodies and microorganisms may act as nidi for the formation of LRs in vivo. LRs in paraffin-embedded tissues have been misdiagnosed as eggs, larvae, and adult components of the giant kidney worm, D. renale.*-" The constancy of size of D. renale eggs (60-80 x 39-47 p) and their periipheral scalloped pattern should help to distinguish them from LRs, which vary greatly in size and have a smooth outer ring. The adult D. renale worm measures 4-12 mm in diameter, whereas LRs greater than 1 mm have not been described. Therefore LRs should not be mistak.en for cross-sections of adult worms. Since entire structures rather than cross-sections are examined in cytologic preparations, the misidentification
200
Diagnostic Cytopathology, Vol6,No 3
1. Liesegang RE. Uber einige eigenschaften von gallerten. Naturwissenschaften 1896;11:353-62. 2. Tuur SM, Nelson AM, Gibson DW, et al. Liesegang rings in tissue. How to distinguish liesegang rings from the giant kidney worm, Dioctophyma renale. Am J Surg Pathol 1987;11:598-605. 3. Baar HS, Ferguson FF. Microlithiasis alveolaris pulmonum. Arch Pathol 1963;76:659-66. 4. Gortner RA. Outlines of biochemistry. The organic chemistry and physiochemical reactions of biologically important compounds and systems. 2nd ed. New York: Wiley, 1938;312-6. 5. Spencer H. Pulmonary corpora amylacea. In: Spencer H, ed. Pathology of the lung. 4th ed. New York: Pergamon, 1985;739-40. 6. Sneige N, Dekmezian RH, Silva EG, Cartwright J Jr, Ayala AG. Pseudoparasitic liesegang structures in perirenal hemorrhagic cysts. Am J Clin Pathol 1988;89:148-53. 7. Sneige N, Dekmezian R, Zaatari GS. Liesegang-like rings in fine needle aspirates of renal/perirenal hemorrhagic cysts. Acta Cytol 1988;32:547-51. 8. Fernando SSE. The giant kidney worm (Diociophyma renale) infection in man in Australia. Am J Surg Pathol 1983;7:281-4. 9. Sun T. The worm turns. Am J Surg Pathol 1987;11:651. 10. Sun T, Turnbull A, Lieberman PH, Sternberg SS. Giant kidney worm (Dioctophyma renale) infection mimicking retroperitoneal neoplasm. Am J Surg Pathol 1986;10:508-12. 11. Vold PD, Vold MJ. Colloid and interface chemistry. London: Addison-Wesley, 1983545-50. 12. Bradford SC. Adsorptive stratification in gels. Biochem J 1916;lO: 169-75. 13. Bradford SC. Adsorptive stratification in gels 11. Biochem J 1917;11:14-20. 14. Davies ECH. Liesegang rings 111. The effect of hydrogen ion concentration on the formation of colloidal gold in silicic acid gel. Rhythmic bands of purple of cassius. J Am Chem Soc 1923;45:2261-8. 15. Hedges ES. Liesegang rings and other periodic structures. London: Chapman & Hall, 1932:l-22. 16. Kirkaldy JS. A continuum theory of liesegang phenomena. Scrip Metal 1986;20:1571-4. 17. Stern KH. The liesegang phenomenon. Chem Rev 1954;57:79-99. 18. Venzl G. Postnucleation theory of liesegang bands. J Chem Phys 1986;85:2006-11.
