Foreign Body Granulomatous Response to Particulate Bony Debris

Archival material was retrieved in order to histologically assess the body’s response to micron-sized, necrotic bony particles. Specimens were obtained from (1) human bone grafts in a subcutaneous or muscular pouch of athymic nude mice, (2) a massive bone allograft replacing a patient’s humerus, (3) rabbits’ healing tibial cortical bone defects littered with finely dispersed bony particles, (4) periprosthetic tissues of patient’s aseptically loosened artificial joints and (5) interfacial membranes of intramedullary nails used for fixation of patients’ fractured long bones. Necrotic bony debris was found to induce a giant celled granulomatous reaction. In sections of undecalcified samples stained by the von Kossa method, small calcific particles were observed to be present within polykaryonic macrophages (foreign body giant cells) and surrounded by mononuclear macrophages. It is concluded that a foreign body-type giant celled granulation tissue participates in the degradation of micron-sized, necrotic bony detritus, whether the disintegrating bone is of the xeno-, alio- or autogenic provenance.

Histological examination of von Kossa-stained sections, of undecalcified specimens, revealed a giant celled granulomatous response to bony debris. Irrespective of whether or not the disintegrating bone was of auto-, alio- or xenogeneic provenance, micron-sized bony particles were found to be phagocytosed by polykaryonic macrophages of the granulation tissue.

Necrotizing Granulomas within the Periprosthetic Tissues of Cemented and Cementless Total Arthroplasties

Necrotizing granulomas were found in the pseudocapsule or interfacial membrane of two patients with an aseptically loosened cemented total hip arthroplasty and in one patient with an aseptically loosened cementless knee arthroplasty. The environs of the necrotizing granulomas disclosed prosthetic debris-induced foreign body granulomatous, chronic inflammatory and cicatrizing changes. Particulate breakdown products of polyethylene and finely dispersed metallic particles were present in the necrotic core, stroma and macrophages of the necrotizing granulomas. A review of the literature and the authors’ personal experience attests to the rarity of such granulomas in the periprosthetic tissues. Polyethylene being non-antigenic, it is suggested that an allergic-pathergic reaction to metallic ions released in loco from the prosthesis itself, from the deposited metallic wear particles or from both accounts for the development of the necrotizing granulomas.

Vasculature deprivation-induced osteonecrosis of rats' femoral heads associated with the formation of deep surface depressions

An impeded blood flow through the femoral head is incriminated in the etiopathogenesis of osteonecrosis of the femoral head. The disorder is either primary (idiopathic avascular osteonecrosis) or secondary to one condition or another, such as corticosteroid medication, fracture of the neck, coagulation defects, physical or thermal damage, storage disorders, alcoholism, and infectious, autoimmune as also marrow infiltrating diseases. In the wake of the necrosis, several mediators are released in increased amounts, prime among which is the vascular endothelial growth factor. The intermediates recruit endothelial progenitor cells, macrophages, osteoclasts, fibroblasts, and osteoblasts, which, pervading throughout the necrotic areas, initiate the reparative processes. The dead, soft, and hard tissular debris is substituted by fibrous - later on by hematopoietic-fatty tissue - and bone. The newly formed, appositional and intramembranous bone is deficient in its mechanical properties. The ordinary load-carrying functions suffice to deform these weakened femoral heads so that osteoarthritic changes develop. Considering contemporary assumptions of the causes of osteonecrosis, oxygenation, revascularization, and core decompression are the realistic therapeutic interventions. Necrosis of rats' femoral heads is studied as a model of osteonecrosis in both adults and children. In view of rodents' lifelong persisting physeal cartilage, vascular deprivation-induced osteonecrosis in rats mimics children's Perthes disease. The experimental model, which is well suited to test treatment modalities, has been used to investigate the effects of exposure to hyperbaric oxygen with and without non-weight bearing, medication of enoxaparin, and creation of an intraosseous conduit on the remodeling of the avascular necrotic femoral head. Intriguingly, the shape of treated rats' femoral heads is disfigured to a greater degree than that of untreated animals. This is most likely due to the reduced yield strength and elastic modulus as well as the raised strain-to-failure of the recently formed bone making up the post-necrotic femoral heads. It follows that expedited osteogenesis is, counter intuition, detrimental to maintaining the hemispherical shape of the femoral head, and thus to an articulation with congruent load-bearing surfaces. If this is indeed the case, the remodeling of the necrotic femoral head should be delayed, rather than sped up, as the present day paradigm would have it. Bearing in mind that the dead osseous structures keep their mechanical attributes for quite a while, a slowed down new bone formation would favor the gradual replacement of the necrotic by living bone. Therefore, management of the adult patients with osteonecrosis and children with Perthes disease should focus on a slowly progressive substitution so that the decline of the bone's mechanical properties is kept to a minimum. One viable therapeutic mode is a medication of inhibitors of the vascular endothelial growth factor.

Do forceps biopsies truthfully reflect the nature of endoscopically uncovered polypoid lesions of the colon?

BACKGROUND

Total excision of colonic polyps is not always attainable and in some patients it is clinically contraindicated. Also, a resected polyp may be lost at any step between its endoscopic removal and its embedding in paraffin. The aim of this study was to compare the histological features of colonic polyps as analysed by the study of biopsy-forceps obtained samples with those assessed on scrutinizing the totally resected growths.

PATIENTS AND METHODS

This prospective study included a cohort of 59 patients in whom, in the course of an elective colonoscopy, a total excision of a 6 mm-sized or larger polyp was called for. Sizeable biopsies were obtained by means of an Olympus Multibyte forceps prior to the total polypectomy. Subsequent to the study of the polypectomy specimens, the forceps biopsy samples were submitted for histological examination. The pathologists were blinded as to the source of the tissue they were studying. The diagnoses rendered by evaluating the biopsy samples and polypectomy specimens of each patient were contrasted with each other.

RESULTS

Major discrepancies between the histological features of the fragments captured by the biopsy-forceps and the factual nature of the totally removed polyps were uncovered in 11 (18.6%) of 59 cases. Intriguingly, the grade of the tumours was underrated in all the 11 cases, as judged by contrasting the tentative diagnoses of the forceps-biopsies with the decisive diagnoses of the polypectomies. Importantly, 2 adenocarcinomas would have been missed by just looking at the forceps-retrieved sample.

CONCLUSIONS

In our experience, a discordance of 18.6% is to be expected between the diagnoses rendered after examining forceps-biopsies of and totally excised colonic polyps. Nevertheless, it is advisable to procure biopsies prior to the excision of the growths, because on those occasions in which patients' growths cannot be removed or have not been retrieved for one reason or another, a small forceps-captured tissue sample correctly reflects the characteristics of the polyp in 81.4% of the cases. Finally, the biopsies may be discarded in the event that total removal was successful.

The fasciitis-panniculitis syndrome presenting as complex regional pain syndrome type 1: report of a case

A 28-year-old man presented with a clinical picture suggestive of complex regional pain syndrome type I following a blow to the thenar eminence and thumb. Symptoms, including swelling of the hand and distal forearm, progressed until an amputation was carried out to rid the patient of an unendurable painful and nonfunctioning wrist and hand. The histologic evaluation of the amputation specimen showed: 1) dermal edema, perivascular dermatitis, and epidermal hyperkeratosis; 2) subcutaneous chronic inflammation with subtotal replacement of the adipose lobules by fibrous tissue associated with thickening of the muscular fascia, implying the fasciitis-panniculitis reaction pattern; 3) atrophy, degeneration, necrosis, and focal calcifications of the skeletal muscles; 4) phlebosclerosis, phlebectasias and lymphocytic arteritis; and 5) increased cortical porosity of the bones. It seems that the pathogenetic process underlying the fasciitis-panniculitis syndrome may rarely manifest as a complex regional pain syndrome-like disorder.

Experimentally gained insight - based proposal apropos the treatment of osteonecrosis of the femoral head

An impeded blood flow through the femoral head is incriminated in the etiopathogenesis of osteonecrosis of the femoral head. The disorder is either primary (idiopathic avascular osteonecrosis) or secondary to one condition or another, say, corticosteroid medication, fracture of the neck, coagulation defects, physical or thermal damage, storage disorders, alcoholism, and infectious, autoimmune as also marrow infiltrating diseases. In the wake of the necrosis, several mediators are released in increased amounts, prime among which is the vascular endothelial growth factor. The intermediates recruit endothelial progenitor cells, macrophages, osteoclasts, fibroblasts, and osteoblasts, which, pervading throughout the necrotic areas, initiate the reparative processes. The dead, soft and hard tissular debris is substituted by fibrous - later on by hematopoietic-fatty tissue - and bone. The newly formed, appositional and intramembranous bone is deficient in its mechanical properties. The ordinary load-carrying functions suffice to deform these weakened femoral heads so that osteoarthritic changes develop. Considering contemporary assumptions of the causes of osteonecrosis, oxygenation, revascularization, and core decompression are the realistic therapeutic interventions. Necrosis of rats' femoral heads is studied as a model of osteonecrosis in both adults and children. In view of rodents' lifelong persisting physeal cartilage, vascular deprivation-induced osteonecrosis in rats mimics children's Perthes disease. The experimental model, which is well suited to test treatment modalities, has been used to investigate the effects of exposure to hyperbaric oxygen with and without non-weight bearing, medication of enoxaparin, and creation of an intraosseous conduit on the remodeling of the avascular necrotic femoral head. Intriguingly, the shape of treated rats' femoral heads is disfigured to a greater degree than that of untreated animals. This is most likely due to the reduced yield strength and elastic modulus as well as the raised strain-to-failure of the recently formed bone making up the post-necrotic femoral heads. It follows that expedited osteogenesis is, counter intuition, detrimental to maintaining the hemispherical shape of the femoral head, and thus to an articulation with congruent load-bearing surfaces. If this is indeed the case, the remodeling of the necrotic femoral head should be delayed, rather than sped up, as the present day paradigm would have it. Bearing in mind that the dead osseous structures keep their mechanical attributes for quite a while, a slowed down new bone formation would favor the gradual replacement of the necrotic by living bone. Therefore, management of the adult patients with osteonecrosis and children with Perthes disease should focus on a slowly progressive substitution so that the decline of the bone's mechanical properties is kept to a minimum. One viable therapeutic mode is a medication of inhibitors of the vascular endothelial growth factor.

Localization of vascular endothelial growth factor during the early reparative phase of the rats' vessels deprivation-induced osteonecrosis of the femoral heads

The expedited revascularization of the rats' avascular, necrotic femoral heads suggests the operation of angiogenic factor(s). The blood circulation of the epiphysis was interrupted by cutting the cervical periosteum and the ligamentum teres of rats' femoral heads. Three days postoperatively, the marrow was necrotic. Seven days postoperatively, the subchondral bony plate and trabecular bone were necrotic as well. The joint capsule was distended by myriad, so-called synovial fibroblasts, all of which were virtually immunoreactive with an antibody to vascular endothelial growth factor. The expression of this factor in the synovial membrane of non-operated rats was limited to preexisting blood vessels. Revascularization of necrotic, avascular femoral heads makes up the essential step in the chain of events terminating in the repair processes, that is, resorption of the necrotic debris and its substitution by newly formed bony and hematopoietic-fatty tissues. Synthesis and release of excessive amounts of vascular endothelial growth factor by these fibroblasts explain the lively angiogenesis in the necrotic intertrabecular spaces of the femoral heads.

Postosteonecrotic osteoarthritis-like disorder of the femoral head of rats

The femoral heads of 15 rats were studied histologically 3 months after the induction of ischaemic necrosis by incising the cervical periosteum and cutting the ligamentum teres. The epiphyses consisted of immature disorganized subchondral and trabecular bone. The inter-trabecular spaces contained fibrous or haematopoietic tissue. Residual necrotic bone was rare. There was marked osteoblastic and osteoclastic activity. The articular aspect of the heads showed a spectrum of changes, ranging from cartilaginous degeneration with fibrillation and loss of glycosaminoglycans to an eburnated and polished bony surface. In seven rats, transphyseal bridges connected the epiphyseal and metaphyseal bony trabeculae to each other. It is suggested that the postnecrotic reparative processes, including the resorption of the necrotic debris and its replacement by newly formed, weak bone, led to an osteoarthritis-like disorder. This healing pattern of the necrotic femoral head was reminiscent of the progressive remodelling that occurs in rings in femoral capital osteonecrosis of adult human patients and in Perthes's disease of children.

Osteonecrosis of the femoral head of laboratory animals: the lessons learned from a comparative study of osteonecrosis in man and experimental animals

Animal models of osteonecrosis of the femoral head are indispensable to the understanding of successful treatment modalities for avascular necrosis of the femoral head in adults and in children with Legg-Calvé-Perthes disease. Many of these models adequately reflect the current "vascular deprivation" theory regarding the etiology of the disease. In addition to spontaneous occurrence, surgical- and corticosteroid-induced models are suitable, common experimental ones. Osteonecrosis of spontaneously hypertensive rats appears to be due to defective bone formation and compression of the arteries entering the femoral head at its lateral facets by daily weight-bearing loads. Successful modeling of surgical-induced femoral capital necrosis can be a challenge in animals with a dual epiphyseal blood supply. High doses of corticosteroids are a pivotal risk factor in the development of osteonecrosis. The pathogenesis of corticosteroid-induced osteonecrosis likely resides in reduced blood flow. Steroids may reduce blood flow by numerous mechanisms, including marrow adipocytic hypertrophy leading to sinusoidal compression, venous stasis and, eventually, obstruction of the arteries, and arterial occlusion by fat emboli and lipid-loaded fibrin-platelet thrombi. Other, less common varieties of osteonecrosis include those secondary to endotoxin-induced disseminated intravascular coagulation, immune reactions, immoderately low or high temperatures, and high-impact-related injuries. Common to these diverse forms of osteonecrosis are fibrin thrombi clogging arterioles and small arteries.

Computer-assisted image analysis of the rat postosteonecrotic remodeled femoral head

Osteonecrosis of rat femoral heads was induced by stripping the periosteum of the neck and cutting the ligamentum teres. The epiphyseal marrow and bone were necrotic on the 5th postoperative day. Specimens obtained 18 and 36 days postoperatively showed fibrous and hematopoietic-fatty tissue in the intertrabecular spaces, osteoclastic bone resorption, osteogenesis, and degeneration of the joint cartilage. Morphometrically, the means of the height-to-length ratios of the control, 6-day, 18-day, and 36-day femoral heads were 0.26, 0.28, 0.48, and 0.29, respectively. The shape factor of the femoral heads of the control rats was higher than 0.81 in 80% of the cases, while those of rats killed on the 6th, 18th, and 36th postoperative day were higher than 0.81 in 65, 60, and 50% of cases, respectively. Statistically, the means of the height-to-length ratios and the values of the shape factors of the femoral heads of the rats killed 18 days postoperatively differed significantly from those of the other three groups of rats. The quantitatively gauged data of the remodeled epiphyses negate the authors' subjective impression concerning early flattening of the femoral heads after surgically produced osteonecrosis.

Coincident Warthin's tumor and intraparotid dermatopathic lymphadenopathy. Report of a case

A 52-year-old patient underwent excision of a parotid lump which was fond to consist of a Warthin's tumor coexistent with a lymph node involved in dermatopathic lymphadenopathy. A preoperative fine-needle aspiration specimen contained brown pigment-granule-laden macrophages within the background of many lymphocytes. Failure to correctly diagnose the parotid tumor was likely due to a sampling error.

Severe hepatotoxicity with jaundice associated with paroxetine

Hepatotoxicity due to paroxetine, a selective serotonin reuptake inhibitor, is very rare, and to the best of our knowledge, only five cases of liver injury in association with paroxetine have previously been reported in the medical literature. We describe the clinical, biochemical, and pathological findings in a patient with paroxetine hepatotoxicity, which was reversed after withdrawal of the drug. The present case and the others previously reported suggest that hepatotoxicity should be taken into account as a rare complication, sometimes severe, that may occur with paroxetine.

Transphyseal osseous bridges in experimental osteonecrosis of the femoral head of the rat. Histologic study of the bony bridges connecting the epiphyseal with the metaphyseal bony trabeculae through gaps in the physeal cartilage

In view of the lifelong persistence of the physis, the femoral head of rats may serve to model Perthes disease and slipped capital femoral epiphysis. To produce osteonecrosis, the blood supply of one femoral head of 133, 6-month-old animals was severed by circumferentially incising the periosteum of the neck and cutting the ligamentum teres. The rats were killed 7 days to 90 days postoperatively. Associated with resorption of the necrotic bone and marrow, remodeling of the epiphysis was characterized by an ingrowth of vascularized fibrous tissue, formation of new bone and some cartilage, architectural deformation and flattening of the head. In 22 of 83 rats killed 30 days or more postoperatively, gaps in the continuity of the physeal cartilage were occupied by osseous bridges, connecting newly formed epiphyseal bony trabeculae with either the preexisting or newly formed metaphyseal osseous trabeculae. This healing mode may follow ischemic death of physeal chondrocytes or be owing to another mechanism, e.g., release of mediatory substances of inflammation. These findings raise the possibility that fixation of the healing epiphysis of a child's previously necrotic femoral head to the metaphysis occurs by transphyseal osseous growth in cases in which the physis is involved in the necrotic process.

Neuroendocrine cells along the digestive tract express neuropilin-2

Neuropilin-2 (np-2) is a receptor for semaphorin-3F (sema-3F) and semaphorin-3C (sema-3C). These semaphorins repel tips of growing axons that express np-2. In addition, np-2 functions as a receptor for heparin binding forms of the angiogenic factor vascular endothelial growth factor (VEGF) such as VEGF145 and VEGF165. We report that np-2 is strongly expressed in neuroendocrine cells located all along the human digestive tract. Confocal fluorescent microscopy revealed that np-2 is concentrated in vesicle-like structures located near the nucleus at the basolateral side of these cells. In the colon, the np-2-expressing subpopulation of neuroendocrine cell is almost identical with the serotonin-producing subpopulation of neuroendocrine cells. Gastrointestinal carcinoid tumors are digestive tract tumors that develop from neuroendocrine cells. Interestingly, most of the carcinoid tumors derived from the colon and the appendix did not contain np-2-producing cells. However, some carcinoid tumors derived from the small intestine and stomach did express low levels of np-2 in isolated foci of cells. By contrast, strong serotonin and chromogranin-A expression was observed in all of the carcinoid tumors that were examined. These results suggest that loss of np-2 expression may accompany tumor progression in carcinoid tumors.

Morphologic and morphometric study of patellar resurfacing with woven carbon filamentous pads

Analysis of retrieved woven carbon filamentous pads, used for resurfacing of the patellar joint surface, disclosed a 4-zonal organizational pattern. Zone 1, facing the articular cavity, was devoid of carbon filaments and consisted of fibrous tissue. Foreign body granulation tissue and fibrous tissue occupied about one-third and approximately 50%-60% of the interfilamentous space in zones 2 and 3, respectively. Carbon filaments formed 2%-9% of zone 2 and 14%-16% of zone 3. An interfacial membrane-like zone 4 separated the carbon filamentous pads from a trabecular bony shell. The bone volume within the latter was approximately 25%. Given that the purpose of articular resurfacing with implants is repopulation of the defect by chondrocytes producing a cartilaginous matrix, the woven carbon filamentous pads did not fulfill this expectation. In an environment of an ongoing foreign body-induced granulomatous reaction, the stem cells permeating the interstices of the woven carbon filamentous pad are apparently incapable of maturing into highly differentiated cells (chondrocytes) synthesizing a highly complex (cartilaginous) matrix.

The biomechamcal and surgical solutions for patella implant in total knee arthroplasty

A basic fault in designs of patella implants that calls for a prompt remedy is the inadequate polyethylene thickness in contact areas. The requirement for thickness of patella implants should be similar to the requirement set up by the FDA in 1993 regarding the tibial implants, that is, a minimal thickness of 8 mm. A solution is presented for the optimal design of the patella implant and for the appropriate surgical technique. The implant's undersurface that fixes to bone is concave and has a 1-cm wide but 5 to 6 mm short central peg that does not risk the integrity of the bone. Fixation of the concave aspect to the convex aspect of the bony patella strongly enhances resistance to medio-lateral and supero-inferior shear forces. The circumferential facet of the implant 8 mm thick assures uniform thickness of the entire implant and assures optimal mechanical properties of the polyethylene. The articulating surface is tailored to conform to the corresponding femoral trochlear groove and condyles. It can be made to fit any femoral component of any knee implant.

Histomorphometric analysis of the normal adult patella

The patellae of 6 male and 2 female, 40 to 70 year-old individuals, who were healthy at the time of their violent death, were assessed by computer-assisted image analysis. The means of the bone density (percentage of bone in the respective field of interest) ranged from approximately 20% to approximately 30% in the central spongiotic zones, from approximately 40% to approximately 80% in the superior and inferior peripheral zones, and approximately 40% to approximately 60% in the subchondral zone. Bone densities were greatest in the lateral parts of the subchondral and spongiotic territories. The bony trabeculae were haphazardly distributed in the central spongiotic zones. They were commonly oriented vertically or parallel to the surface of the patella in the peripheral and subchondral zones. In conclusion, the histomorphometric data presented validate the rationale of reaming the articular aspect of the patella into a dome-shaped configuration with preservation of a circumferential bony bulwark in the preparation for the implantation of a thick polyethylene-based component with a concave undersurface.

Computer-assisted image analysis can aid the prognostication of advanced-stage neuroblastomas

PURPOSE

The aim of this work was to detect nuclear parameters related to the prognosis of patients with stage III, IV or DS neuroblastomas.

METHODS

Histological sections of 25 operation specimens obtained from children with advanced-stage neuroblastomas were subjected to computer-assisted image analysis. Statistical relationships between nuclear descriptors of the tumor cells and patients' clinical outcome were determined.

RESULTS

The coefficient of variability of the mean nuclear area the mean nuclear elongation factor, and the mean nuclear averaged Feret diameter of the neuroblastoma cells were ascertained to be discriminators separating high-grade from low-grade tumors.

CONCLUSIONS

The histomorphometrically gauged nuclear parameters may help oncologists to assess the prognosis of patients with advanced-stage neuroblastoma.

Lymph-node-based malignant lymphoma and reactive lymphadenopathy in eosinophilic fasciitis

BACKGROUND

Lymph node enlargement in patients with eosinophilic fasciitis is a rare occurrence and its clinical significance is unknown.

METHODS

The literature and authors' registries were searched for eosinophilic fasciitis associated with lymphadenopathy. Clinical data, time sequence of appearance of either disorder, and pathological diagnoses were analyzed.

RESULTS

Six patients presenting with eosinophilic fasciitis had a lymph-node-based lymphoma and 4 patients had a reactive lymphadenopathy. The patients with lymphoma were elderly and the subcutaneous induration preceded the lymphadenopathy by 2 to 36 months. The patients with eosinophilic fasciitis and reactive lymphadenopathy were young and the onset of subcutaneous induration and lymph node enlargement coincided with one another. Favorable response of the eosinophilic fasciitis to prednisone therapy was attained in 3 of 3 patients with reactive lymphadenopathy and in 4 of the 6 cases with lymphoma.

CONCLUSIONS

Eosinophilic fasciitis is rarely associated with clinically significant lymph node enlargement. Subcutaneous induration preceding the lymphadenopathy by 6 months or more, especially in elderly patients, suggests an underlying lymphoma. A favorable response of the subcutaneous induration to prednisone treatment does not exclude the diagnosis of lymphoma; therefore, it does not supersede the need of a pathological evaluation. A lymph node biopsy is mandatory in all cases.

Osteoarthritis-like disorder in rats with vascular deprivation-induced necrosis of the femoral head

The reparative processes following vascular deprivation-induced necrosis of the femoral head were studied histologically in rats sacrificed 2, 7, 14, 21, 42 and 92 days postoperatively. The blood supply was severed by incision of the periosteum at the neck of the femoral head and transection of the ligamentum teres. Granulation tissue and a well-vascularized fibrous tissue originating from the joint capsule invaded the necrotic marrow spaces. With progressive resorption of the necrotic tissues and osteoneogenesis, both appositional and intramembranous, within the fibrotic intertrabecular spaces, the remodeling process led to a shift of the normal spongy architecture of the femoral head to a compacta-like one. In a few cases, osseous bridges bisected a necrotic physeal cartilage at the latest time intervals. The remodeling was associated with flattening of the femoral heads as well as with degenerative, regenerative and reparative alterations of the articular cartilage. In one of the two femoral heads obtained three months postoperatively, cystic spaces developed in the fibrous subchondral zone. Our findings are consistent with the view that ineffective attempts at restoring the prenecrotic state of the femoral head by replacing the necrotic with viable tissue triggers the collapse of the femoral head. Thickening and condensation of the subchondral bone, leading to increased stiffness of the subchondral zone, result in the osteoarthritis-like disorder. Mimicking the well-known phases of human osteonecrosis, the model readily allows for preclinical studies of therapeutic regimens.

Treatment of experimental avascular necrosis of the femoral head with hyperbaric oxygen in rats: histological evaluation of the femoral heads during the early phase of the reparative process

The healing of vascular deprivation-induced necrosis of the femoral head of rats exposed to hyperbaric oxygen was compared with that in untreated rats. The amount of necrotic bone, extent of osteoneogenesis, degree of remodeling, and changes of the articular cartilage were histologically graded on a semiquantitative scale of 0 to 3+. On the 2nd, 7th, and 21st postoperative days, there were no differences between the two groups. Newly formed appositional and intramembranous bone was more abundant and remodeling was more advanced in the femoral heads of the hyperbaric oxygen-treated than untreated rats sacrificed on the 42nd postoperative day; also there was less necrotic debris in the femoral heads of the treated rats. There were no differences in the severity of the degenerative changes of the articular cartilage of the treated and untreated rats. Exposure of rats to hyperbaric oxygen does not preserve tissue viability after all arteries supplying the femoral head are severed. Yet, resulting in an increased oxygen tension of the tissues, it seems to provide the optimal settings for reparative processes. The results suggest that hyperoxygenation-mediated relief of ischemia enhances the fibroblastic, angioblastic, osteoblastic, and osteoclastic activities such that healing of the rats' necrotic femoral heads is expedited.

The value of histomorphometric nuclear parameters in the diagnosis of well differentiated follicular carcinomas and follicular adenomas of the thyroid gland

AIMS

To explore the potential of histomorphometric analysis in distinction between follicular adenomas and well differentiated follicular carcinomas of the thyroid gland. Their differentiation on routine histological study may be a challenging exercise, being contingent upon the absence or presence of vascular invasion and penetration of neoplastic follicles through the capsule of the tumour.

METHODS AND RESULTS

Computer-assisted image analysis was performed to gauge the nuclear area, nuclear Ferret diameter, nuclear regularity factor, nuclear elongation factor, number of nuclear vesicles and total area of all nuclear vesicles in the follicles of 37 adenomas and 36 well differentiated carcinomas. By univariate analysis, these nuclear descriptors (with the exception of the elongation factor) were found to correlate with the benign or malignant nature of the tumours. By multivariate analysis, only the nuclear area, Ferret diameter and regularity factor were ascertained to be significant predictors of malignancy. A fitted logit model correctly predicted 91% of the cancers and 87% of the adenomas.

CONCLUSIONS

Histomorphometrically gauged nuclear parameters of the tumour cells may reinforce pathologists' decision-making by adding objective and unbiased criteria to their subjective assessment of follicular neoplasms in cases in which vascular or capsular invasion are not detected.

Acute lipase-induced panniculitis in rats with ligated veins of the hindlimb: a contribution to the role of acute panniculitis as a precursor of lipodermatosclerosis of venous disease

The authors studied the effect of ligation of the femoral and saphenous veins on the evolution of lipase injection-induced subcutaneous fibrosis and inflammation in the rats' hindlimbs. The superficial muscular fascia was thickened and the number of veins was increased 3 days and 3 weeks after vein ligation; both abnormalities disappeared 6 weeks postoperatively. Vein ligation did not quantitatively affect fascial thickening or fibrosing panniculitis in hindlimbs injected with lipase 6 weeks prior to sacrifice. The results contradict the proposition that lipase-induced injury of rats' subcutaneous tissues compromised by venous stasis may lead to a persistent chronic inflammation and fibrosis of the subcutaneous-fascial complex duplicating lipodermatosclerosis in man.

Computer-assisted image analysis of small cell lymphoma of the thyroid gland. Comparison of nuclear parameters of small lymphocytes in lymphomas and Hashimoto's thyroiditis

The nuclear parameters of the small lymphocytes in nine cases of small cell lymphomas of the thyroid gland and 17 cases of Hashimoto's thyroiditis were assessed by computer-assisted image analysis. The nuclear area, maximal, minimal and averaged Ferret diameters, perimeter, regularity factor and elongation factor were gauged. Statistically, the nuclear area was ascertained to be the optimum descriptor discriminating between small neoplastic and reactive lymphocytes. Application of a novel variable, combining a nuclear area cut-off value of 14 microm2 with a nuclear averaged Ferret diameter cut-off value of 4.5 micron, allows for the distinction - with a high degree of sensitivity and specificity - between small neoplastic lymphocytes in thyroidal lymphomas and the reactive lymphocytes in Hashimoto's thyroiditis.

The fasciitis-panniculitis syndromes: histomorphometric assessment of the inflammatory and sclerosing processes affecting the subcutaneous and fascial tissues

BACKGROUND/AIMS

The fasciitis-panniculitis syndromes include several disorders characterized by skin induration due to fibrotic thickening of the septa of the subcutis and muscular fascia associated with chronic inflammation. Representative of the idiopathic form, eosinophilic fasciitis, is the prototype of the fasciitis-panniculitis syndromes. Secondary forms of the syndromes are causally related to a variety of diseases, such as infections, circulatory disorders, physical injuries and neoplasms.

METHODS

Histological sections of 10 idiopathic and 20 secondary cases of the fasciitis-panniculitis syndromes were assessed by means of computer-assisted image analysis. The percent of fibrous tissue, referred to as "extent of fibrosis", and the number of lymphocytes, macrophages, eosinophils, plasma cells, and mast cells within the subcutaneous-fascial complex were assessed.

RESULTS

The "extent of fibrosis" varied from 1% to 2% in the control cases and from 4% to 98% in the index cases. The number of inflammatory cells per high power field varied from 0 to 33 in the control cases and from 9 to 323 in the index cases.

CONCLUSIONS

There is a direct and positive correlation between the "extent of fibrosis" and the number of inflammatory cells. The "extent of fibrosis" and intensity of the inflammatory infiltration do not correlate with the nature of the underlying diseases, the patients'demographic data, the anatomic location of the subcutaneous induration or the duration of the lesion. It is suggested that the fasciitis-panniculitis syndromes are the morphological expression of a chronic, relapsing, inflammatory-sclerosing reaction pattern that is essentially identical in the idiopathic and the secondary forms of the disorder.

Colonic ulcers in a patient with hepatitis C virus-associated polyarteritis nodosa

An elderly woman presented with abdominal discomfort, pulmonary infiltrates, acute renal failure, purpura, and massive hematochezia. Numerous colonic ulcers with underlying fibrinoid necrotizing arteritis were found in the colectomy specimen. Anti-hepatitis C virus (HCV) antibodies and HCV RNA were present in the serum. The diagnosis of HCV-associated polyarteritis nodosa was clear. This clinical presentation differs from the more commonly occurring vasculitis complicating HCV infection, which is of the leukocytoclastic type, and is associated with overt liver disease and cryoglobulinemia. In our patient, results of liver tests were normal, there was no cryoglobulinemia, and the vasculitis was of the fibrinoid necrotizing arteritis type. HCV-associated polyarteritis nodosa should be considered in the differential diagnosis of necrotizing fibrinoid arteritis even in a patient with normal liver function test results and in the absence of cryoglobulinemia.

Comparative study of computer-assisted image analysis and light-microscopically determined estrogen receptor status of breast carcinomas

BACKGROUND

Efficient tamoxifen treatment of breast cancer patients depends on the degree to which pathologists are consistently able to use the so-called "modified quickscore" method to differentiate between negative and low-grade positive scores based on the current four-grade scale of the estrogen receptor (ER) status of the tumors.

OBJECTIVE

To quantitatively test pathologists' ability to adequately render correct readings of the ER status of breast tumors.

METHODS

The ER status of breast carcinomas was estimated by two pathologists and measured by computer-supported analysis in sections stained with ER antibody by the immunoperoxidase technique. Levels of agreement between the examiners' semiquantification and histomorphometrically gauged measurements were compared statistically.

RESULTS

The kappa coefficients were 0.28 on a case-by-case collation of the grades of nuclear staining, 0.52 on applying binary categories of positively versus negatively stained cell nuclei, and 0.89 using binary categories with a weighted score of 1.2 to separate ER-negative from ER-positive breast carcinomas.

CONCLUSIONS

The findings suggest that an optimum rating system is achieved by assigning tumors with a weighted score of 1.2 or less to the ER-negative and those with a weighted score of 1.3 or more to the ER-positive category of breast carcinomas.

Autosomal-recessive omodysplasia: prenatal diagnosis and histomorphometric assessment of the physeal plates of the long bones

Second-semester ultrasonography of a female fetus documented short femora and humeri and dislocation of the radii. Based on the clinical and postmortem radiological findings, autosomal-recessive omodysplasia was diagnosed. The physeal plates of the long tubular bones were assessed by computer-assisted image analysis. The dimensions and orientation of the chondrocytic lacunae in the physeal plates of the omodysplastic fetus were compared with those in the physeal plates of fetuses without gross limb abnormalities (oligohydramnios, n = 2; hydrocephalus, n = 2; Down syndrome, n = 1). The pathological characteristics of the omodysplastic physeal plates were an expanded zone of proliferating cartilage and an increased number of closely packed, small chondrocytes. We propose that a genetic, functional deficiency of the physeal cells, underlying the short-limbed dwarfism of autosomal-recessive omodysplasia, is partially compensated, albeit ineffectively, by an increased number of small chondrocytes in the proliferating zone of the physeal plate.

Status of intraoperative cytology in the diagnosis of epithelioid hemangioma

Whereas evaluation of the frozen section of a subcutaneous retro-auricular mass was equivocal, the correct diagnosis of epithelioid hemangioma could be suggested on examination of intraoperative cytological smears. It is proposed that in the absence of cytological cues of malignancy and in the presence of the proper clinical setting, the constellation of vascular structures, eosinophils, lymphocytes, and clusters of cuboidal cells with vacuoles in their abundant acidophilic cytoplasm is indicative of epithelioid hemangioma.

Cellular dysplasia in acquired cystic renal disease: comparison of histomorphometrically gauged nuclear parameters in normal kidneys, renal cell carcinomas and acquired cystic kidneys

Nuclear parameters were assessed by computer-assisted image analysis in the cells of abnormal epithelial formations in the acquired cystic kidneys of two dialysis patients, the proximal and distal tubules of a normal kidney and two well differentiated renal cell carcinomas. One acquired cystic kidney contained many small clear celled foci and am 0.9 cm-size clear celled lesion and the second one a papillary microadenoma. The clear celled lesion was cytologically indistinguishable from the carcinomas. The histomorphometrically gauged nuclear parameters were maximal and minimal ferret diameters, averaged ferret diameter, aspect ratio, shape factor, area, volume and specific length and width. Statistical evaluation evidenced that the nuclear area, volume, aspect ration and shape factor allowed for the distinction between benign and malignant epithelial structures. The medians of the nuclear parameters of atrophic tubules, cysts, clear celled foci, papillary adenoma and clear celled lesion in the two acquired cystic kidneys deviation from those of normal renal tubules and in, increasing order of disparity, approached those of the carcinomas.

Acute cor pulmonale due to tumor cell microemboli

Severe pulmonary hypertension due to tumor cell microemboli or lymphangitic carcinomatosis is a rare complication of malignant disease. In most of the reported cases, a clinical picture of subacute cor pulmonale developed. A 57-year-old man with deep vein thrombosis in his left calf developed acute progressive dyspnea with hypoxemia, cyanosis and the clinical picture of acute cor pulmonale, while he was on full heparinization. Respiratory failure with the need for mechanical ventilatory support developed within 2 days. Chest radiography revealed the development of acute cardiac enlargement, dilated pulmonary artery and diffuse opacities in the fields of both lungs. Open lung biopsy disclosed massive tumor cell microemboli and lymphangitic carcinomatosis. No parenchymal metastases were found. This case is extremely rare because of the rapid development of the patient's respiratory signs and symptoms of acute cor pulmonale due to pulmonary tumor cell microemboli and lymphangitic carcinomatosis. It is also most atypical because of the rare pulmonary radiographic presentation.

Salivary gland double tumor: synchronous ipsilateral pleomorphic adenoma and acinic cell carcinoma of the parotid gland

A 44-year-old woman underwent a partial parotidectomy for a slowly enlarging parotid mass diagnosed by fine needle aspiration biopsy as a pleomorphic adenoma. Though macroscopically recognized to be composed of two nodules, differing to some extent from one another, the mass appeared to constitute a single tumor. The microscopic examination disclosed two disparate neoplasms, which were separated from each other by a thin fibrous band. The larger of the two nodules was a pleomorphic adenoma and the smaller one an acinic cell carcinoma. The metachronous--and, even more, the synchronous--occurrence of two histologically different tumors in one major salivary gland is an exceptional and probably coincidental event.

An experimental model of fasciitis-panniculitis. Induction of chronic fibrosing panniculitis in the rat by subcutaneous injections of lipase

We describe an experimental model of the fasciitis-panniculitis syndrome, which includes eosinophilic fasciitis and its related disorders. Rats were given a single or repeated subcutaneous injections of saline or a 10% lipase solution. The injection sites were studied histologically and histomorphometrically. With few exceptions, the subcutaneous-fascial unit of the saline-injected rats was normal. An acute necrotizing panniculitis with inflammatory involvement of the adjacent fascia was found 2 days after a single injection of lipase. Three to 6 weeks after a single injection of lipase, the subcutaneous fat tissue and fascia were fibrotically thickened and chronically inflamed. Similar but more advanced alterations had developed in animals killed 3 weeks after three weekly injections of lipase. Progressive fibrotic thickening of the subcutaneous-fascial unit was observed following an increasing number of weekly lipase injections. The acute-phase reaction expresses a pattern of steatonecrotic tissue damage. In the ohronic phase, the fibrotically thickened subcutaneous layers typify a reaction pattern analogous to that of the human fasciitis-panniculitis syndrome. This experimental model permits better appreciation of the disorder's nonspecific pathogenesis and may help in the search for alternative therapeutic modalities.

The fasciitis-panniculitis syndromes. Clinical and pathologic features

The authors propose to encompass under the designation of "fasciitis-panniculitis syndromes" (FPS) a group of disorders characterized by induration of the skin due to chronic inflammation and fibrosis of the subcutaneous septa and muscular fascia. The prototype of the FPS is eosinophilic fasciitis. Thirty-two consecutive patients with FPS were cared for at the author's hospital during a 10-year period. The association of the FPS with other diseases, clinical presentations, histologic features, and response to treatment were analyzed. Idiopathic FPS, that is, eosinophilic fasciitis, was diagnosed in 14 patients. In the remaining 18 cases, the FPS were ascribed to vascular disorders (n = 6), infections (n = 6), and neoplastic disorders (n = 3), while trauma, insect bites, and Sweet syndrome antedated the FPS in 1 patient each. The lesions had a sleeve-like distribution in 20 patients, plaque-like distribution in 7, and a combined pattern in 5. Skin biopsies revealed lesions in the deep subcutaneous layers with the pathologic triad of septal and fascial fibrosis, chronic inflammatory infiltration, and small-vessel vasculopathy. Spontaneous improvement occurred in 4 cases. Following cimetidine monotherapy, complete remission was achieved in an additional 3 of 5 patients. The concept of the FPS serves to advance our understanding on several fronts: emphasizing the clinical and etiologic diversity; recognizing a stereotypic tissue reaction pattern; highlighting the panniculitis in addition to the fasciitic component; and describing a similar response to drug therapy in different clinical settings. Based on the results of the present series, cimetidine may be recommended as first-line treatment.

Histologic analysis of the periprosthetic tissues of long-term surviving cemented total hip arthroplasties

Qualitative and semiquantitative features of the interfacial membranes of five long-term (> 16 years) surviving cemented total hip arthroplasties (four revision cases and one autopsy case) were compared with those of thirty short-term surviving (< 15 years) cemented hip prostheses. Cement granulomas, micron-sized polyethylene particles-induced giant-celled granulomas, sheets of submicron-sized polyethylene particles-laden macrophages, and aggregated, metallic particles-laden macrophages were scattered in the fibrous tissue of all interfacial membranes. Quantitatively, characteristics of the interfacial membranes of the two groups differed from one another. The dominant species of prosthetic debris in the interfacial membranes of the short-term surviving joint replacements was derived from the polyethylene acetabular socket, and, correspondingly, giant-celled granulomas and macrophagic sheets predominated. Metallic particles and the macrophagic reaction thereto dominated in the interfacial membranes of the long-term surviving arthroplasties, and large cement and polyethylene chunks typically were incorporated in the fibrous tissue of the membranes without an accompanying macrophagic response. In long-term surviving hip arthroplasties, metallic particles may be at least as important as polymeric detritus in stimulating the formation of the bone-resorbing, granulomatous interfacial membrane, which is the hallmark of aseptically loosened arthroplasties. Differences in mechanical settings may account for unlike modes and rates of generation of prosthetic breakdown products, explaining the disparate survivorship of different patients' artificial joints.

Idiopathic granulomatous appendicitis. Report of five cases, one of which presented as migratory arthritis

The clinical presentation of acute appendicitis and the idiopathic granulomatous variety are, as a rule, indistinguishable. Five patients with idiopathic granulomatous appendicitis, treated during past decade, had histological acute and chronic appendicitis abounding with granulomas. Investigations not disclosing a systemic or enteric granulomatous disease and the patients' long-term complete postoperative recovery support the diagnosis of idiopathic granulomatous appendicitis.

Dirofilaria repens infection in northern Israel

The fourth case of zoonotic Dirofilaria repens infection in Israel is reported, and the diagnostic morphologic characteristics of this filariid are reviewed. The importance of the exact anatomic diagnosis of this filaria is stressed in view of the fact that Israel has pockets of settlers from East Africa, a region endemic for lymphatic filariasis (Wuchereria bancrofti). Since the possibility of introduction of such an infection into the country exists, differentiating this zoonotic Dirofilaria from other filarial worms is essential. The clinicopathological features of a Dirofilaria repens infection are distinct. The patient initially has a painful subcutaneous or conjunctival swelling; the excisional biopsy shows the presence of a dead or alive, usually female worm that measures 220-660 microns across; the central intestine and the genital organs (two uteri) are located in the pseudocoelom; the thick, multilayered cuticle is provided with 95-105 sharp, longitudinal ridges, the latter being separated from each other by a distance of 12 microns; the circumferential muscle cell layer, covering the inner side of the cuticle, is bilaterally interrupted by the large chord cells, two to five nuclei of which are discernible in each cross section.

Small intestinal carcinoma with osteoclast-like giant cells

An elderly woman underwent jejunectomy for a large, stenosing neoplasm. Histologically, we found an undifferentiated carcinoma with scattered mononuclear and multinuclear macrophages in the intestine and lymph node metastases. The multinuclear cells, being acid phosphatase-positive and CD68-immunoreactive, are referred to as osteoclast-like giant cells. Hepatic secondaries were discovered 6 months postoperatively. The patient succumbed to a chemotherapy-related septic event. We suggest that intratumoral infiltration by mononuclear and multinuclear macrophages expresses one of the body's defense mechanisms against cancer.

Acute neutrophilic myositis in Sweet's syndrome: late phase transformation into fibrosing myositis and panniculitis

Early in the course of myeloblastic leukemia a patient concurrently developed febrile neutrophilic dermatosis and sterile acute myositis. The dermatitis and myositis were unresponsive to antibiotic therapy but remitted within a few days of institution of steroid treatment. The patient died of myocardial infarction. At autopsy the dermis was normal. Previously effected muscles were scarred. The overlying fascia and subcutaneous septa were fibrotically thickened. In addition, segmental acute aortitis was detected. Acute myositis and aortitis may reflect further organ manifestations of the Sweet's reactivity pattern. It is proposed that Sweet's myositis and dermatitis may evolve into a fibrosing myositis and panniculitis.

The relativity of biocompatibility. A critique of the concept of biocompatibility

The concept of biocompatibility of the materials used in surgical reconstruction of joints, ligaments, and tendons is controversial, as evinced by the conflicting definitions proposed by the many authors who have studied the host reaction to the presence of implants and their breakdown products. We propose that biocompatibility of contemporary medical implants is not a property of the chemical composition of the biomaterials but depends rather on their physical attributes. The histological reaction patterns of tissue to the presence of polyethylene in diverse physical states are described. The inflammatory response evoked by the implants is laudable in so far as it precedes and accompanies the adequate tissular incorporation of the devices used. On the other hand, the granulomatous reaction induced by small, irregularly shaped and edgy breakdown products adversely affects the life span of the implants. Thus the manner in which the host handles the biomaterials is determined primarily by the physical state of the biomaterials (rather than their chemical composition), which in turn determines the success or failure of reconstructive surgery. It logically follows that biocompatibility constitutes a relativistic concept.

Angiolymphomatoid hyperplasia with eosinophilia of the oral mucous membrane

A 59-year-old patient is reported with a protruding, mucosal nodule within the mandibular alveolar fold. Histological examination of the excised mass disclosed angiolymphoid hyperplasia with eosinophilia (histiocytoid hemangioma). Though the lesion was not completely excised and invaded the adjacent muscle of the floor of the mouth, there was no recurrence during a follow-up period of 17 months.

Remodeling of the calcaneus apophysis in the growing child

Radiography and computer-aided analysis of tomography of the os calcis in 35 children with Sever's disease and of 52 control children were concurrently evaluated with histologic appearance of six calcanei of victims of road accidents, which were radiographically compatible with the same syndrome. Histology showed abrupt interruption in continuity of the apophysis of perpendicular fibrous plates with evidence of an ongoing reparative process. Computer-aided analysis of orientation of the "fragmentation" lines and histologic data both support the hypothesis of a stress remodeling process owing to excessive bending forces acting on the calcaneal apophysis.