Histiocytic Reaction Research Articles

Potential of Migration and Tissue Reactions to Intraperitoneally Implanted Polymethyl Methacrylate in Wistar Rats

Objective: This study aimed to evaluate the performance of polymethyl methacrylate (PMMA) when implanted into the peritoneal cavities of Wistar rats, specifically its potential for migration to the examined organs and possible tissue reactions at the implantation site. Methods: Adult male Wistar rats (290-400 g) were distributed randomly into 2 groups: P4 (n=20), to which 0.4 mL of PMMA was administered; and P2 (n= 0), to which was 2 mL of PMMA were administered. These groups were subsequently divided into 4 subgroups according to the day on which euthanasia occurred (day 1, 7, 14, or 28). Results: The changes in animal weight prior to PMMA implantation and after euthanasia were compared. No nodules or signs of PMMA implantation or any other macroscopic alterations were observed in the spleen, kidneys, lungs, or liver. However, mild-to-moderate inflammatory infiltration in which macrophages, lymphocytes, and neutrophils predominated was observed in at least 1 of the 4 organs examined from each animal during the experimental time points. Mild inflammatory responses were observed that were rich in histiocytes and giant cells and featured increased numbers of blood vessels and fibroblasts in the pericapsular regions of the studied organs. In 29 cases, a greyish material compatible with PMMA was identified. There was no migration of PMMA into the parenchyma of the examined organs. The changes in the tissues were the same regardless of the volume of implanted PMMA. Following staining with HE, the PMMA particles in the tissues were a grayish color, measuring approximately 30-40 μm in size, and were found to have stimulated histiocytic reactions in 29 examined organs. Conclusions: The results showed that the most affected tissues were the visceral peritoneum of the spleen and the kidneys from group P2. Our study may contribute to add a new proof of testing implants.

Staging studies for evaluation of squamous cell carcinoma. Staging of left temporal squamous cell carcinoma with PET-CT.

Primary hyperoxaluria is a rare congenital disorder of abnormal glyoxylate metabolism with resultant over-accumulation of oxalate, which then binds with calcium and precipitates in the kidneys, resulting in nephrocalcinosis and nephrourolithiasis. As renal function worsens, patients develop systemic oxalosis with calcium oxalate deposition in the soft tissues, musculoskeletal system, cardiovascular system, central nervous system, and eyes [1–5]. There are three common types of primary hyperoxaluria (types I–III). Type I is the most common and severe and involves a mutation in the alanine glyoxylate aminotransferase (AGT) enzyme causing overproduction of oxalate glyoxylate [1]. Type II results from deficiency of glyoxylate reductase and hydroxypyruvate reductase (GRHPR), which results in overproduction of oxalate and L-glyceric aciduria [1, 5]. Type III results from mutation in 4-hydroxy-2oxoglutarate aldolase (HOGA) and is the least aggressive hyperoxaluria type, with most patients not progressing to end-stage renal disease (ESRD) [1]. Imaging findings in primary hyperoxaluria vary depending on patient age and renal function [2–6]. Prior to renal function impairment, imaging is frequently normal. As renal failure develops, cortical nephrocalcinosis and nephrourolithiasis will be seen (Fig. 1). Calcium oxalate subsequently deposits in soft tissues, tendons, and joint capsules, with joint effusions and nodular-appearing tumoral calcinosis (especially in periarticular regions, which can cause erosive arthropathy) [2–6]. As ESRD develops toward the late stage of the disease, musculoskeletal imaging manifestations typically associated with renal osteodystrophy and secondary hyperparathyroidism will develop, such as osteosclerosis, subperiosteal resorption, Brugger-jersey^ spine, and vascular/soft tissue calcifications (also seen in Fig. 1). Abnormal skeletal maturation and pathologic fractures with delayed healing can also be seen but are similarly nonspecific. Oxalate deposition in the subcutaneous and dermal tissues can cause skin necrosis/ulceration, and oxalate deposition in the myocardium, pericardium, ocular and vascular regions has also been described [4–9]. Skeletal findings more specific to primary hyperoxaluria may include irregular diametaphyseal transverse sclerotic bands and wide metaphyseal zones [5]. Lytic lesions can be seen in primary hyperoxaluria, which histopathologically represent foci of calcium oxalate deposition with a granulomatous foreign body histiocytic reaction, which appear essentially identical to brown tumors on The case presentation can be found at doi: 10.1007/s00256-015-2161-1.

Use of Acellular Fish Skin for Dura Repair in an Ovine Model: A Pilot Study

Recently the use of biologic materials as dura mater repair patches has been increasing. The purpose of this study is to assess the basis for efficacy and safety of using a novel fish derived acellular dermis (Kerecis Omega3 DuraTM). In an ovine model a craniotomy under general anaesthesia was performed. A defect was produced in the dural covering of approximately 1 × 2 cm and closed with an onlay technique, with Kerecis Omega3 Dura. The bone defect was covered with the bony flap and the overlying tissues closed in layers. At 2, 5, 8 and 11 weeks the sheep underwent MRI scanning followed by euthanasia, necropsy and histological assessment. MRI images taken at 2, 5, 8 and 11 weeks showed initially moderate inflammatory response, which diminished over time, and at 11 weeks no evidence of inflammation existed. There was evidence of cerebrospinal fluid leakage at no time point. Necropsy revealed some adhesions at 5 and 8 weeks, in particular at 5 weeks, but at 11 weeks there were no adhesions found. From 2 - 11 weeks, there was evidence of initially an inflammatory reaction followed by neodura formation at the defect site through cellular ingrowth and remodeling of the acellular fish skin. Histology showed a histiocytic foreign body reaction initially that subsided over time. As early as 8 weeks there was evidence of neodura formation and by 11 weeks there was a minimal inflammatory response with an intact neodura formed. In this pilot study the Kerecis Omega3 Dura patches performed in a safe and efficacious manner. This new material needs to be fully assessed and compared with other products that are currently on the market in a larger scale animal study.

Actinic granuloma arising from the pulsed dye laser-treated skin in a patient with capillary malformation.

Dear Editor: Actinic granuloma is a rare inflammatory skin disorder that presents in chronically sun-damaged skin with flesh-colored to erythematous papules that coalesce to form centrifugally enlarging annular patterns1. However, its pathogenesis remains to be elusive. It is thought that ultraviolet radiation, heat, viral diseases or other unknown factors transform the antigenicity of elastic fibers and induce cellular immune reactions1,2. A 49-year-old Korean woman had reddish patches on the right side of her face from birth. She was diagnosed with capillary malformation about 20 years ago. She has treated the skin lesion with a pulsed dye laser (PDL) and fractional laser >10 times with 7 years. However, her skin lesion has not completely disappeared. On examination, the reddish patch had an uneven surface and firm texture (Fig. 1). These changes in the skin occurred 2 years ago. Histopathologically, there were some telangiectatic vessels and granulomatous inflammation in the superficial and mid-dermis (Fig. 2A). The dermis showed histiocytes with numerous giant cells, and some of them contained elastotic material, which was consistent with actinic granuloma (Fig. 2B, C). Because of previous repeated laser therapy, we presumed that these granulomatous reactions resulted from the laser therapy-induced actinic and/or heat damage. First, she was treated with oral methylprednisolone (8 mg; Methylon; Kunwha, Seoul, Korea) for 4 months and topical desonide (0.05%; Desowen Lotion; Galderma Pharma SA, Lausanne, Switzerland) for 1 year. However, this treatment resulted in no response. Then she was treated with oral isotretinoin (10 mg; Roaccutane; Roche, Basel, Switzerland) for 4 months, but she also had a minimal response. Fig. 1 (A) Ill-demarcated reddish patch with an (B) uneven surface and firm texture on the right side of the face (white arrow: the biopsy site). Fig. 2 (A) Some telangiectatic vessels and granulomatous inflammation in the superficial and mid-dermis (H&E, ×40). (B) The granuloma is comprised of numerous giant cells (H&E, ×200). (C) Some giant cells are contained in the ... Actinic granuloma typically affects exposed, weather-beaten skin in patients who are at least aged >30 years. Predilection sites are the neck, face, chest, and arms. O'Brien3 considered actinic granuloma to be a phenomenon of repair within damaged connective tissue. A biopsy specimen shows three distinct zones in the dermis. At the periphery within normal skin, actinic elastosis is prominent. The annulus shows a histiocytic and giant cell inflammatory reaction in the papillary and mid-dermal region. The giant cells may contain intracytoplasmic degenerated elastic fibers, or they may surround the foci of elastosis. A center, relatively elastin-free zone is present within the annulus3,4. The differential diagnosis includes granuloma annulare and necrobiosis lipoidica. The absence of dermal mucin and the presence of larger, more numerous giant cells help to distinguish actinic granuloma from granuloma annulare. The presence of elastophagocytosis, degenerated collagen, and sclerosis aid in distinguishing actinic granuloma from necrobiosis lipoidica. The treatment of actinic granuloma has been disappointing. Most reports have cited poor response to topical steroids with a single report of a response to isotretinoin5. In our current report, the patient was previously treated with PDL and fractional laser therapy >10 times. She was a housewife living in an urban area. We thought that the actinic granuloma resulted from the repeated laser therapy-induced heat and/or actinic damage. And, the damage may have destroyed the elastic fiber, which triggers an inflammatory response that causes granulomas. We describe an unusual case of actinic granuloma arising from the laser therapy treated skin.

Granuloma inguinal (Donovanosis) de la encía y regiones submandibulares

El granuloma inguinal (Donovanosis) de la cavidad oral es muy raro, sin embargo representa lamanifestación extragenital mas frecuente de esta infección producida por la bacteria gramnegativa Calymmatobacterium granulomatis. Se describe un caso de donovanosis gingival en unhombre homosexual de 19 años de edad. Las lesiones gingivales se presentaron como úlcerasmicrogranulomatosas combinadas con zonas esponjosas. El paciente también tenía lesiones enlas regiones submandibulares y perianal. El diagnóstico se estableció por biopsia gingival. Eneste tejido, las secciones teñidas con hematoxilina - eosina mostraron una marcada reaccióngranulomatosa compuesta por histiocitos, mezclados con abundante cantidad de neutrófilos ypocas células plasmática. Los cuerpos de Donovan fueron identificados usando la coloración deWarthin-Starry . Se discute el diagnóstico clínico diferencial así como el cuadro histopatológico.Considerando el comportamiento sexual del paciente se sugiere que el compromiso gingival ysubmaxilar probablemente representaban múltiples sitios primarios de infección porC.granulomatis. Sin embargo, la autoinoculación no puede ser descartada. Donovanosis debe serconsiderado en el diagnóstico diferencial de lesiones granulomatosas que afectan la mucosa oral,particularmente cuando se presentan en pacientes promiscuos.

Epidural application of spinal instrumentation particulate wear debris: a comprehensive evaluation of neurotoxicity using an in vivo animal model

The introduction and utilization of motion-preserving implant systems for spinal reconstruction served as the impetus for this basic scientific investigation. The effect of unintended wear particulate debris resulting from micromotion at spinal implant interconnections and bearing surfaces remains a clinical concern. Using an in vivo rabbit model, the current study quantified the neural and systemic histopathological responses following epidural application of 11 different types of medical-grade particulate wear debris produced from spinal instrumentation. A total of 120 New Zealand White rabbits were equally randomized into 12 groups based on implant treatment: 1) sham (control), 2) stainless steel, 3) titanium alloy, 4) cobalt chromium alloy, 5) ultra-high molecular weight polyethylene (UHMWPe), 6) ceramic, 7) polytetrafluoroethylene, 8) polycarbonate urethane, 9) silicone, 10) polyethylene terephthalate, 11) polyester, and 12) polyetheretherketone. The surgical procedure consisted of a midline posterior approach followed by resection of the L-6 spinous process and L5-6 ligamentum flavum, permitting interlaminar exposure of the dural sac. Four milligrams of the appropriate treatment material (Groups 2-12) was then implanted onto the dura in a dry, sterile format. All particles (average size range 0.1-50 μm in diameter) were verified to be endotoxin free prior to implantation. Five animals from each treatment group were sacrificed at 3 months and 5 were sacrificed at 6 months postoperatively. Postmortem analysis included epidural cultures and histopathological assessment of local and systemic tissue samples. Immunocytochemical analysis of the spinal cord and overlying epidural fibrosis quantified the extent of proinflammatory cytokines (tumor necrosis factor-α, tumor necrosis factor-β, interleukin [IL]-1α, IL-1β, and IL-6) and activated macrophages. Epidural cultures were negative for nearly all cases, and there was no evidence of particulate debris or significant histopathological changes in the systemic tissues. Gross histopathological examination demonstrated increased levels of epidural fibrosis in the experimental treatment groups compared with the control group. Histopathological evaluation of the epidural fibrous tissues showed evidence of a histiocytic reaction containing phagocytized inert particles and foci of local inflammatory reactions. At 3 months, immunohistochemical examination of the spinal cord and epidural tissues demonstrated upregulation of IL-6 in the groups in which metallic and UHMWPe debris were implanted (p < 0.05), while macrophage activity levels were greatest in the stainless-steel and UHMWPe groups (p < 0.05). By 6 months, the levels of activated cytokines and macrophages in nearly all experimental cases were downregulated and not significantly different from those of the operative controls (p > 0.05). The spinal cord had no evidence of lesions or neuropathology. However, multiple treatments in the metallic groups exhibited a mild, chronic macrophage response to particulate debris, which had diffused intrathecally. Epidural application of spinal instrumentation particulate wear debris elicits a chronic histiocytic reaction localized primarily within the epidural fibrosis. Particles have the capacity to diffuse intrathecally, eliciting a transient upregulation in macrophage/cytokine activity response within the epidural fibrosis. Overall, based on the time periods evaluated, there was no evidence of an acute neural or systemic histopathological response to the materials included in the current project.

Lip Augmentation Dermal Filler Reactions, Histopathologic Features

Instances of perioral and labial foreign body reactions to a variety of injectable dermal fillers were selected from the oral and maxillofacial pathology and dermatopathology archives at Pacific Pathology Laboratory of San Diego with the objective being to engender a compilation of histopathologic characteristics that allow the pathologist to identify the inciting materials. All cases of foreign body reactions located in the lips and perioral regions were reviewed by four pathologists, retaining those cases with a history of injection lip augmentation as well as those with histologic features previously documented to represent dermal filler substances. In selected cases, Alcian blue pH 2.5 with and without hyaluronidase pretreatment was performed. Immunohistochemical markers for macrophages (CD 68), adipocytes (S-100) and keratinocytes (AE1/AE2) were undertaken. All instances presented as single or multiple submucosal plaques, nodules or swellings. Natural polymers including collagen, hyaluronate, hydroxyapatite, poly-L-lactate and synthetic polymers including carboxymethyl cellulose, dimethylpolysiloxane, and polyethyl methacrylate induce histologically unique features that allow for their identification. Host histopathologic responses included nodule without foreign body reaction, nodule with chronic inflammation, granuloma with epithelioid histiocytic and multinucleated giant cell reaction. Dermal filler foreign body host reactions in conjunction with the morphology of the foreign materials themselves are unique and can be differentiated from one another microscopically.

Severe scar problems following use of a locking barbed skin closure system in the foot

Barbed sutures provide a novel technique for knotless wound closure. They have mainly been used in plastic and general surgery. There are no reports about its use in the foot. We present a case series of 11 feet in 8 patients whose wounds were closed with barbed sutures. Ten had primary hallux valgus correction and one had a revision correction. No problems were noted at 2-weeks follow-up. Four of the 11 cases required open suture excision due to an adverse reaction. Five were followed to delayed wound healing. Histology results from one scar showed a localised histiocytic reaction and superficial dermal abscess formation. We feel the thin subcutaneous tissue of the foot, the amount of motion and pressure from the shoe causes the barbs to repeatedly irritate the soft tissue. Based on our short case series we cannot recommend the use of a barbed skin closure system in the foot.

Cellular Spindled Histiocytic Pseudotumor Complicating Mammary Fat Necrosis

Fat necrosis of the breast is a relatively common reactive/reparative process that may be either primary, often after trauma, or secondary to prior surgery or therapeutic irradiation. Mammary fat necrosis may closely mimic breast neoplasia, both clinically and radiographically, and is thus frequently biopsied. In the majority of cases fat necrosis in the breast shows classic morphologic features and is a straightforward diagnosis. However, over the past several years we have seen a number of more challenging cases of mammary fat necrosis complicated by a distinctive cellular, spindled proliferation of macrophages, mimicking various spindle cell neoplasms of the breast. Herein we report our experience with such lesions. A total of 118 cases of fat necrosis involving the breast were retrieved from our institutional and consultation archives for the period 1994 to 2011. The final study group of 20 cases included only (1) consultation cases submitted specifically with concern for a spindle cell neoplasm and (2) institutional cases presenting as a mass lesion and showing an identical spindle cell proliferation. The tumors occurred in 20 women (mean age 58 y; range, 24 to 70 y), involved both breasts (left, 11 cases; right, 9 cases), and ranged in size from 0.8 to 2.5 cm (mean 1.5 cm). Additional clinical information was available for 18 (90%) patients; a history of ipsilateral breast carcinoma and prior therapeutic irradiation were documented in 7 of 18 (39%) and 6 of 18 (33%) patients, respectively. Radiographic reports and/or imaging was available for 17 (85%) patients; radiographic impressions were "suspicious for malignancy" (10 cases, 59%), "indeterminate" (2 cases, 12%), or "benign" (5 cases, 29%). The patients underwent core needle (14 cases, 70%) and excisional (6 cases, 30%) biopsies. The morphologic features of all cases were similar, showing a moderately cellular, fascicular proliferation of mitotically active, normochromatic, lightly eosinophilic spindled cells with mild nuclear variability, folded or grooved nuclei, and indistinct nucleoli. Chronic inflammatory cells and multinucleated giant cells were often admixed with the spindled cells, with more typical features of fat necrosis frequently present at the periphery. Immunohistochemical analysis performed at Mayo Clinic showed the lesional cells to express the histiocyte-associated markers CD163 (8 of 8, 100%), CD11c (8 of 8, 100%), and CD31 (4 of 8, 50%) and to be negative for keratins using the OSCAR monoclonal antibody (0 of 8, 0%). Studies conducted at outside institutions showed absent expression of various keratins, S100 protein, p63, and β-catenin protein. Histochemical staining for mycobacterial and fungal organisms was negative. Follow-up (18 patients, 1 to 120 mo, mean 37 mo) showed all patients to be alive without disease. Additional surgical procedures (6 patients) showed only fat necrosis. We believe that these lesions represent an exaggerated histiocytic reaction to fat necrosis in the breast. Awareness of this distinctive pseudotumor should help to prevent its misdiagnosis as various other mammary spindle cell neoplasms.

Down-staging (&lt;pT2) of urothelial cancer at cystectomy after the diagnosis of detrusor muscle invasion (pT2) at diagnostic transurethral resection (TUR): is prediction possible?

Urothelial cell carcinoma (UCC) with musculus detrusor (MD) invasion is treated by cystectomy. Subsequent pathologic evaluation of cystectomies does not reveal MD invasion (<pT2) in a subgroup of patients. Our objective was to identify features at diagnostic transurethral resection (TUR) predicting down-staging (<pT2) at cystectomy. Patients with pathologically confirmed MD invasion at TUR followed by cystectomy for UCC without (neo-) adjuvant therapy were included (N = 106). Slides of both TUR and cystectomy specimens were reviewed, and survival analyses were performed. In total, 27/106 (26 %) tumors were down-staged at cystectomy, of which 13 (12 %) had no residual tumor (pT0). There was no significant difference in age, gender, time interval between TUR and operation, number of slides sampled, and presence of TUR scar between down-staged (<pT2) and pT2 UCC. At review of TUR specimens (N = 52) with UCC initially diagnosed as pT2, MD invasion was not confirmed in eight cases (15 %). One case showed extensive histiocytic reaction misinterpreted as UCC; in four cases, muscularis mucosae had been considered MD, and in three cases, desmoplastic reaction mimicked MD. No histologic parameter at TUR was significantly associated with down-staging at cystectomy. Overall and disease-specific survival was not statistically different in down-staged and pT2 UCC. In conclusion, down-staging of UCC (<pT2) at cystectomy occurred in 26 %. At review of diagnostic TURs, MD invasion was not confirmed in 15 %. No clinical or pathologic parameter was predictive for down-staging at cystectomy. There was no difference in survival between down-staged and pT2-staged UCC.

Comparison of 4% icodextrin and omega 3 Fatty acids in prevention of peritoneal adhesions.

Postoperative peritoneal adhesions are major concerns in abdominal surgery. In this experimental study, the effects of 4% icodextrin and omega-3 fatty acids (ω-3 FA) on prevention of postoperative peritoneal adhesions were evaluated. Twenty-four Wistar albino rats were divided into three groups. After laparotomy, serosal abrasion was carried out by cecal brushing. Intraperitoneally 3cm(3) 0.9% NaCl, 3cm(3) 4% icodextrin, and 200mg/kg ω-3 FAs for each group were applied, and then the abdomen was closed. All subjects sacrificed 10days postoperatively. Macroscopic and histopathological cellular reactions as a function of giant cell, lymphocyte/plasmocyte, neutrophil, histiocyte, intracellular adhesion molecule-1 (ICAM-1), and platelet endothelial cell adhesion molecule-1 (PECAM-1) were assessed and hydroxyproline levels were measured in all three groups and compared using Kruskal-Wallis and ANOVA tests when appropriate. Macroscopically, both ω-3 FAs and 4% icodextrin reduced adhesion formation but the difference was not statistically significant (P = 0.253). Histopathological examination revealed that there was no statistical significance in terms of giant cell, lymphocyte/plasmocyte, neutrophil, ICAM-1, and PECAM-1 scores; however, both ω-3 FAs and 4% icodextrin were found to be prone to reduce fibrosis (P = 0.047), whereas in the ω-3 FA group, histiocytic reaction was significantly increased (P = 0.001), and hydroxyproline levels were significantly lower than other groups (P = 0.044). In this study, ω-3 FAs were found to be superior to 4% icodextrin with the lower hydroxyproline level and greater histiocytic reaction. Considering these results, ω-3 FAs can be a promising agent in the prevention of adhesion formation.

Possible Migration and Histopathological Analysis of Injections of Polymethylmethacrylate in Wistar Rats

Objective. To evaluate the possible migration of polymethylmethacrylate after injections in various corporal compartments of Wistar rats. Methods. The experimental work consisted in the injection of PMMA in corporal compartments for later histopathological analysis of the locations of implants and of distant filtering organs. The dose applied in each implant was of 0.2 mL. The animals were divided into groups according to the location of the implant realized: group GB had intradermic injections in the glabella. Group SD had subdermal injections in dorsal subcutaneous tissue cells. Group IP had intraperitoneal injections in the abdomen. Group PD had intramuscular injections in the right rear leg. The rats were sacrificed 30 days after realization of the implants and tissue samples from the lung, liver, spleen, and kidney, and locations of implantation were removed for histopathological analysis. Results. Characteristic microspheres that were compatible with the presence of PMMA in any of the histological slides analyzed were not observed. One animal had an amorphous exogenous substance, with a histiocytic reaction. Twelve of the 16 lungs analyzed had locations of intraalveolar hemorrhaging. Two animals had nonspecific spleen alterations. Conclusion. The histopathological analysis of this study found no PMMA microspheres in any of the tissues analyzed.

Adhesion-preventing properties of 4% icodextrin and canola oil: a comparative experimental study

OBJECTIVE:Postsurgical abdominal adhesions are common, serious postoperative complications. The present study compared the usefulness of 4% icodextrin and canola oil in preventing postoperative peritoneal adhesions.METHODS:Twenty-four Wistar albino rats were divided into three groups. Following a laparotomy, a serosal abrasion was made by brushing the cecum, and 3 mL of 0.9% NaCl, 4% icodextrin, or 3 mL of canola oil were intraperitoneally administered for the control, icodextrin, and canola oil groups, respectively. The abdomen was then closed. All of the rats were sacrificed at day 10. Macroscopic, histopathological, and biochemical evaluations were performed. The results were statistically analyzed using Kruskal–Wallis and ANOVA tests.RESULTS:Macroscopic analyses revealed that both canola oil and 4% icodextrin reduced adhesion formation, but the difference was not statistically significant (p = 0.17). The histopathological examinations revealed no significant differences in terms of giant cell, lymphocyte/plasmocyte, neutrophil, ICAM1, or PECAM1 scores. However, both canola oil and 4% icodextrin significantly reduced fibrosis (p = 0.025). In the canola oil group, the histiocytic reactions were significantly increased (p = 0.001), and the hydroxyproline levels were significantly lower than those in the other groups (p = 0.034).CONCLUSIONS:In the present study, canola oil was determined to be superior to 4% icodextrin in lowering hydroxyproline levels and increasing histiocytic reactions. Considering these results, we believe that canola oil is a promising agent for preventing adhesion formation.

Infektiöse Lymphadenitiden

Infectious lymphadenitis is often biopsied in the differential diagnoses of malignant disease. Since the repertoire of lymph nodes which react to exogenous stimuli is limited, malignant lymphomas may enter the clinical and morphological differential diagnosis. In a morphological sense, infectious lymphadenitis is defined as an infection of lymph node tissue. Therefore, the effector phase of the inflammatory reaction will act against lymphatic tissue, in contrast to common physiological hyperplasia. Follicular reactions, in addition to follicular hyperplasia, are seen in HIV-associated lymphadenopathy. Other viruses, such as infectious mononucleosis, give rise to a cytotoxic T-cell reaction. Most infections, however, induce a histiocytic reaction; depending on the microorganism, this varies morphologically from a small clustered epithelioid cell reaction or histiocytic abscesses to epithelioid necrotizing granulomata.

Carbon Nanotubes: Biocompatibility of Immobilized Aligned Carbon Nanotubes (Small 8/2011)

AbstractIn vivo host responses to an electrode‐like array of aligned carbon nanotubes (ACNTs) embedded within a biopolymer sheet are reported. This biocompatibility study assesses the suitability of immobilized carbon nanotubes for bionic devices. Inflammatory responses and foreign‐body histiocytic reactions are not substantially elevated when compared to negative controls following 12 weeks implantation. A fibrous capsule isolates the implanted ACNTs from the surrounding muscle tissue. Filamentous nanotube fragments are engulfed by macrophages, and globular debris is incorporated into the fibrous capsule with no further reaction. Scattered leukocytes are observed, adherent to the ACNT surface. These data indicate that there is a minimal local foreign‐body response to immobilized ACNTs, that detached fragments are phagocytosed into an inert material, and that ACNTs do not attract high levels of surface fouling. Collectively, these results suggest that immobilized nanotube structures should be considered for further investigation as bionic components.

Mycobacterium mageritensePulmonary Disease in Patient with Compromised Immune System

<i>Mycobacterium mageritense</i>Pulmonary Disease in Patient with Compromised Immune System

Biocompatibility of Immobilized Aligned Carbon Nanotubes

In vivo host responses to an electrode-like array of aligned carbon nanotubes (ACNTs) embedded within a biopolymer sheet are reported. This biocompatibility study assesses the suitability of immobilized carbon nanotubes for bionic devices. Inflammatory responses and foreign-body histiocytic reactions are not substantially elevated when compared to negative controls following 12 weeks implantation. A fibrous capsule isolates the implanted ACNTs from the surrounding muscle tissue. Filamentous nanotube fragments are engulfed by macrophages, and globular debris is incorporated into the fibrous capsule with no further reaction. Scattered leukocytes are observed, adherent to the ACNT surface. These data indicate that there is a minimal local foreign-body response to immobilized ACNTs, that detached fragments are phagocytosed into an inert material, and that ACNTs do not attract high levels of surface fouling. Collectively, these results suggest that immobilized nanotube structures should be considered for further investigation as bionic components.

Granular Cell Tumour of the Thyroid Gland: A Case Report and Review of the Literature

Granular cell tumours of the thyroid gland are rare, with only six previously reported cases in the English literature. Current histological, immunohistochemical and electron microscopic evidence favours a neural/Schwannian relationship. A case of a granular cell tumour of the thyroid gland in a healthy 36-year-old woman is described. The tumour was found incidentally following a right thyroid lobectomy for symptoms from an asymmetric multinodular goitre. Macroscopically, the lesion resembled a papillary microcarcinoma. Microscopically, the tumour was composed of nests of epithelioid cells with abundant granular, eosinophilic cytoplasm. The nests were divided by fibrous septa and peripherally interdigitated with surrounding thyroid follicles. Immunohistochemistry helped to distinguish the lesion from other neoplasms such as Hurthle cell tumour, medullary carcinoma or metastasis, and also from a histiocytic reaction to previous fine needle aspiration. On the basis of this diagnosis, no further intervention was required, and the patient was discharged following post-operative review.

Peritoneal histiocytic reaction associated with oxidised regenerated cellulose, a form of mucicarminophilic histiocytosis

Sir,Oxidised regenerated cellulose (ORC) is a topical haemostatic agent widely used to control surgical bleeding at many different sites. It is also effective in reducing the incidence and extent o...

Postchemotherapy Histiocyte-Rich Pseudotumor Involving the Spleen

We report 2 cases of splenic postchemotherapy histiocyte-rich pseudotumor. Each patient had a history of diffuse large B-cell lymphoma, treated with multiagent chemotherapy. Computed tomography scans performed on both patients showed splenic masses. A positron emission tomography scan performed on 1 patient showed increased metabolic activity. The preoperative diagnosis in both patients was recurrent lymphoma, prompting splenectomy. The splenectomy specimens showed multiple, tan-white, firm nodules, up to 3.5 cm in diameter, that were histologically composed of central necrotic B cells (CD20+/CD3-), consistent with necrotic lymphoma, surrounded by numerous lipid-laden (xanthomatous) histiocytes. Clinical staging studies at the time of splenectomy showed no other sites of disease. We conclude that these histologic and immunophenotypic findings represent chemotherapy-induced tumor necrosis with a florid histiocytic reaction mimicking residual viable lymphoma. Others have used descriptive terminology or the term xanthomatous pseudotumor for these lesions that have been only rarely reported in the spleen previously.