Multinucleated Histiocytes Research Articles

Granulomatous Acute Interstitial Nephritis Revealing Multisystem Sarcoidosis Associated with Thyroiditis and Cushingoid Syndrome: Report of a Case and Review of the Literature

Introduction: Sarcoidosis can present with acute renal failure (ARF) due to granulomatous interstitial nephritis (GIN). We report the case of granulomatous acute renal failure (ARF) revealing multisystemic sarcoidosis in the nephrology department of the Aristide Le Dantec hospital in Dakar. Observation: Mrs. kD aged 54 with a past history of high blood pressure for 22 years, a multi nodular euthyroid goiter, referred to the nephrology department for impaired renal function. The clinical examination revealed at entry, deterioration in the general condition with weight loss and non-selective anorexia. Clinical anemia was also noted. The clinical examination also revealed Cushingoid syndrome and dry mouth syndrome. On biology, the blood count showed bicytopenia with anemia at 10.9 g/dl and leukopenia at 2620/mm3. There was an impairment of renal function with creatinine at 139.2 mg/l and blood urea at 1.76 g/l. The renal ultrasound became normal. Cervical ultrasound showed an aspect of abscessed thyroiditis of the right lobe. Chest computed tomography (CT) showed bilateral hilar adenomegaly and a band of bilateral basal linear atelectasis. The renal biopsy showed glomeruli of subnormal structure, the interstitium is riddled with tuberculoid follicles formed of epithelioid and multinucleated histiocytes of the Langhans type. The diagnosis of granulomatous acute interstitial nephritis revealing multisystemic sarcoidosis was kept. The evolution was favorable after 1 month of treatment with corticosteroid therapy with a clear improvement in renal function. Conclusion: Renal manifestations during sarcoidosis are rare. They can be indicative of the disease as in our patient. Renal biopsy is essential in any patient presenting with impaired renal function with extra-renal signs.

High expression of interleukin-17A in cutaneous sarcoidosis.

Increasing evidence of Th17 pathways is implicated in sarcoidosis granulomatous inflammation and maintenance. Our study evaluated the presence of IL-17A, a downstream proinflammatory cytokine, in cutaneous sarcoidosis biopsies. We found that all 26 biopsy samples had increased expression of IL-17A, predominantly located in macrophages within granulomas, in the cytoplasm of multinucleated histiocytes surrounding the granulomas and within lymphocytic infiltrates surrounding the inflammation.

Pigmented Multinucleate Cell Angiohistiocytoma: Not So Infrequent?

To the Editor: In 2022, we described the first case of pigmented multinucleate cell angiohistiocytoma (MCAH), demonstrating that the pigment showed positivity with the Masson–-Fontana histochemical technique, while being negative with iron technique.1 At this time, no additional cases of this pigmented variant have been published. However, we have recently identified a second case of pigmented MCAH with similar staining characteristics by histochemical studies. The patient is a 58-year-old woman with a 3-year history of lesions on the back of her hands. The lesions were asymptomatic, although they had gradually increased in number and size. At the time of consultation, the patient had a total of 10 lesions, and a biopsy was performed on the largest lesion (5 mm in diameter). The histopathological study demonstrated a typical case of MCAH (Fig. 1A) with dermal fibrosis, numerous vessels, and polygonal multinucleated histiocytes (Fig. 1B) expressing CD68 (Fig. 1C), CD10, and FXIIIa. Some of the histiocytes showed cytoplasmic brownish pigment (Fig. 2A). This pigment did not stain with the Perls iron histochemical technique (Fig. 2B), but showed strong staining with Fontana-Masson (Fig. 2C), consistent with melanin.FIGURE 1.: A, Multinucleated cell angiohistiocytoma. At this magnification, the lesion appears as a conventional MCAH, with dermal fibrosis, prominent vasculature, and perivascular histiocytic infiltrate (Hematoxylin–-eosin ×40x). B, Some of the histiocytes exhibit angular polygonal conformation (Hematoxylin–-eosin ×20x). C, Expression of CD68 by the histiocytic component of the lesion (×100x).FIGURE 2.: A, Some of the histiocytic cells in the tumor contain brownish cytoplasmic pigment (Hematoxylin–-eosin ×400x). B, The pigment did not stain with the iron histochemical technique (×100x). C, The pigment was positive with the Fontana–-Masson technique (×200x).This finding of a second case in just over a year since the publication of the first one makes us think that, given the low frequency of this entity, the pigmented variant of MCAH may not be so exceptional. It is possible that the amount of pigment varies from case to case and that, therefore, many cases with mild amounts of pigment likely go unnoticed or are diagnosed without being published. Although in the discussion of our first case, we stated that the pigment was consistent with melanin, lipofuscin also stains with the Masson–-Fontana technique. Lipofuscin is a brownish lipid pigment that is considered a “"wear and tear”" or “"cellular aging”" pigment, because it is thought to result from the peroxidation of polyunsaturated lipids in subcellular membranes by free radicals. It is generally observed in cells with intense oxidative enzyme activity.2 In ultrastructural studies, lipofuscin deposits appear as cytoplasmic granules of varying sizes.3 Regarding this, we have performed additional techniques in both cases, including periodic acid-Schiff (PAS), Ziehl–-Neelsen, and Sudan black, which also stain lipofuscin.4 We have also examined the biopsy with an immunofluorescence microscope, becauseas it is known that lipofuscin shows autofluorescence. The pigment in both cases was negative by PAS staining, did not stain with Ziehl–-Neelsen, and did not show autofluorescence. Thus, it does not exhibit the staining or microscopic properties of lipofuscin. On the contraryHowever, both cases present properties consistent with melanin. We have not found any more cases published in the literature. There is a series of sclerosing hemangiomas from 1943, but the drawings of the microscopic observations suggest that they are lesions very different from MCAH.5 Additionally, the pigment demonstrated in some of the cases in that series was clearly identified as iron by its histochemical properties.5

A case of metallosis mimicking cutaneous malignant melanoma following total elbow arthroplasty

AbstractMetallosis manifests as an abnormal dark macroscopic staining of periprosthetic tissues by metallic particles from the prosthesis. This complication is uncommon in non‐weight‐bearing joints such as the elbow. We describe a rare case of metallosis mimicking cutaneous malignant melanoma following total elbow arthroplasty (TEA). A 77‐year‐old Japanese woman presented to our clinic with a black nodule within a blue‐greyish pigmentation on the left elbow. She had undergone a left TEA 8 years before presentation. X‐ray showed an amorphous increased density shadow accompanied by high‐density substances in the periprosthetic tissues, consistent with the features of metallosis. Surgical debridement and prosthetic removal were performed. Histopathological examination of the pigmented skin around the nodule revealed a dense infiltration of histiocytes with brownish to blackish granular particles in the dermis. The black‐stained periprosthetic tissues exhibited many multinucleated giant cells and histiocytes with similar particles. Additionally, analysis of the paraffin sections containing particles and the scanning electron microscope‐energy dispersive X‐ray spectroscopy (SEM‐EDX) revealed that the metal was composed of titanium and aluminium, which were components of the prosthesis. At the patient's first visit to our clinic, cutaneous malignant melanoma was considered as a possible differential diagnosis based on the clinical appearance. To the best of our knowledge, previous cases of metallosis with this clinical presentation have not been reported.

Anisometric Cell/Dysplastic Lipomas in a Retinoblastoma Survivor: Report of a Case with Review of the Literature.

Different authors have recently described a subtype of lipoma characterized by variation of adipocyte size, single cell fat necrosis, and a subset with minimal to mild nuclear atypia, and termed these as anisometric cell/dysplastic lipoma (AC/DL). These lipomas follow a benign course and rarely recur. In 3 examples, AC/DL has occurred in patients with childhood retinoblastoma (RB). We report another such example where multiple AC/DL occurred in the neck and back of a 30-year-old male who had germline RB1 gene deletion and bilateral RB in infancy. On excision, all tumors histologically showed similar morphology of adipocyte anisometry, focal single cell necrosis with surrounding binucleated or multinucleated histiocytes, hyperchromatic and minimally atypical lipocyte nuclei, vacuolated Lockhern change, rare foci of fibromyxoid change, occasional mononuclear cell clusters around capillaries, and loss of RB1 immunostaining. Unequivocal atypical cells, lipoblasts, floret-nucleated or multinucleated giant cells were absent. Molecular analysis of tumor cells showed monoallelic RB1 gene loss without amplification of MDM2 and CDK4 genes. Short-term follow up did not show tumor recurrence. AC/DLs in RB survivors are characterized by multiplicity, unifying histology, and benign course. Their biology appears distinct from ordinary lipomas, spindle cell lipomas, and atypical lipomatous tumors.

Eruptive papules on axillary folds of an adolescent.

Eruptive papules on axillary folds of an adolescent.

Primary extranodal soft tissue Lennert lymphoma (lymphoepithelioid variant of peripheral T-cell lymphoma, unspecified): a case report and review of the literature

Lennert lymphoma (LeL) is a rare variant of peripheral T-cell lymphoma, not otherwise specified (PTCL/NOS) that is rich in epithelioid histiocytes. LeL may pose great diagnostic and therapeutic challenges to the pathologist and clinician. Primary extranodal soft tissue LeL is even rarer and has not been reported. Herein, we report a case of LeL arising from soft tissue.A 65-year-old male presented for evaluation of a painless mass in the subcutaneous soft tissue of the left forehead. There was no invasion of the bone and no ulceration on the surface of the skin. The surrounding skin was erythematous and swollen. Grossly, the tumor was gray-red and 30 mm × 20 mm × 10 mm in size.Microscopically, the demarcation between the lesion and surrounding tissues was unclear without a capsule. The tumor invaded the surrounding striated muscle and adipose tissue. The tumor had a diffuse proliferation of small-sized atypical lymphocytes and numerous large clusters of epithelioid histiocytes. Plasma cells, eosinophils, and Hodgkin-Reed-Sternberg (HRS) cells were not identified. Rare multinucleated histiocytes were noted, and well-formed granulomas were not present. Rare mitotic figures were noted, but no necrosis. The immunophenotypic features in this case were as follows: CD2+/CD3+/CD5low+/CD7+/CD4low+/ CD8+/CD30−/CD56− in neoplastic lymphocytes; CD163+/CD31+/CK(pan)− in epithelioid histiocytes; and CD20−/CD30−/TdT−/CD5−/ALK−/S-100−/CD1α−/CD21 + 23−/SSTR2− in neoplastic lymphocytes and epithelioid histiocytes. Epstein-Barr virus (EBV)-encoded RNA in situ hybridization (EBER-ISH) was negative. The Ki-67 index was elevated to 60%. PCR showed a polyclonal pattern for IgH and a monoclonal TCR γ-chain rearrangement.The final diagnosis was PTCL/NOS, lymphoepithelioid cell variant (LeL), which arose from soft tissue and had a rare double-positive CD4low+/CD8+ immunophenotype. The patient received four cycles of cyclophosphamide, doxorubicin liposomes, vincristine, and prednisone tablets (CHOP) and was followed for 20 months. Overall treatment efficacy was achieved without lymphadenopathy, and no other discomfort or illnesses were reported.

Clinical manifestations and imaging and pathological features of giant cell angioblastoma: Report of four cases and literature review.

Giant cell angioblastoma is a relatively rare vasogenic tumour. To date, studies on its clinical manifestations, imaging characteristics, pathological features, and prognosis are extremely limited and unknown, with only a few cases recorded. In this study, four cases of giant cell angioblastoma confirmed by pathological examination were reported to improve our understanding and deep exploration of the tumour spectrum. All cases in our study were male, including two adults and two boys. The lesions were located in the lower segment of the femur, medial condyle of the femur, knee joint, and popliteal fossa. Regarding the imaging characteristics, two patients with lesions in bone showed bone destruction, while the other two had lesions that invaded soft tissues, showing irregular, abnormal signal shadows and obvious enhancement. Histopathological analysis revealed that the nodular tumour tissue was mainly composed of oval and spindle cells, with varying numbers of osteoclast-like multinucleated giant cells, and the interstitial tissues were often filled with blood vessels of different sizes. The immunophenotype demonstrates that endothelial cells of small vessels in nodules expressed CD31, SMA, and ERG, while osteoclast-like multinucleated giant cells and histiocytes expressed CD68 and CD163, and the surrounding cells expressed SMA. All four patients were treated with surgical resection. One of them relapsed 1 month after surgery and received a second surgical resection. No distant metastasis or death occurred during the follow-up period. This study indicates that giant cell angioblastoma is a local invasive vascular tumour that can develop both in children and adults with skin, mucous membrane, soft tissue, and bone involvement. Imaging characteristics show bone destruction and irregular, abnormal signal shadows; in addition, obvious pathological morphological features can be observed. Currently, the treatment is mainly surgical resection, and interferons may be used as adjuvant chemotherapy.

Deep Dermatophytosis Presented as Multiple Exophytic Masses caused by Trichophyton rubrum in Immunocompromised Patient with Rheumatoid Arthritis; A Case Report

Dermatophytes invade the stratum corneum and infect the skin, nails, and hair, mostly resulting in superficial infections. Deep dermatophytosis involving the dermis and subcutaneous layer has rarely been reported in immunocompromised individuals. Herein, we report a case of deep dermatophytosis caused by Trichophyton rubrum. A 71-year-old woman presented with multiple erythematous exophytic and subcutaneous nodules in both the lower legs. The patient was taking immunosuppressive agents for rheumatoid arthritis and antifungal agents for tinea pedis and onychomycosis, which was improperly ceased. Histopathological findings showed diffuse granulomatous infiltration with multinucleated cells, lymphocytes, histiocytes, and neutrophils in the dermis. Septate and branched hyphae were observed in the dermis using periodic acid-Schiff diastase and Gomori methenamine silver staining. T. rubrum was identified in fungal culture from the tissue sample and confirmed through phylogenetic analysis of the internal transcribed spacer and large subunit regions in ribosomal ribonucleic acid gene. Intravenous amphotericin B was administered for septic shock before the confirmation of the causative organism, which rapidly improved the condition.

Diepoxy-treated bovine jugular vein conduit for pulmonary artery replacement

Objective: To evaluate the performance and short-term capacity of the diepoxy-treated bovine jugular vein conduit in large animals during 6-month follow-up.Methods: Thirteen diepoxy-treated bovine jugular vein conduits were implanted into the pulmonary artery of young mini-pigs. During the follow-up, graft function was tested using transesophageal echocardiography. The animals were withdrawn at 6 months, and the explanted conduits were assessed histologically.Results: All the conduits were successfully implanted without any surgical complications. All the animals survived throughout the follow-up. By the end of the follow-up period, the pressure gradient increased on five animals’ conduits including one case of mismatch between the conduit and the native pulmonary artery, two cases of distal stenosis, and two case of endocarditis. No significant increase in valve regurgitation or conduit thrombosis was observed during the follow-up. In conduits without dysfunction, the structure of the walls and leaflets was intact. A thin fibrous tissue covered the conduit inner wall with complete surface endothelialization. Neither signs of degeneration or calcification nor inflammatory cells were found in the conduit wall or leaflets. Neointima proliferation without calcium deposits was observed in two distally stenosed conduits. Inflammatory cells consisting of multinucleated macrophages, lymphocytes, and histiocytes were found in the adventitia. There were no inflammatory cells in the media or intima, and the leaflets showed no changes.Conclusion: Diepoxy-treated bovine jugular vein demonstrated acceptable performance, good endothelialization, and low tendency to thrombosis and calcium accumulation in the wall and leaflets. Received 31 October 2022. Revised 25 November 2022. Accepted 28 November 2022. Funding: The study was supported by Russian Science Foundation (grant No. 22-25-20102). Conflict of interest: The authors declare no conflict of interest. Contribution of the authorsConception and study design: N.R. Nichay, I.Yu. Zhuravleva, A.V. Bogachev-ProkophievData collection and analysis: N.R. Nichay, Yu.Yu. Kulyabin, I.S. Zykov, E.V. Boyarkin, O.Yu. Malakhova, E.V. Kuznetsova, T.P. Timchenko, Ya.L. Rusakova, I.S. Murashov, A.A. DokuchaevaStatistical analysis: N.R. Nichay, I.Yu. ZhuravlevaDrafting the article: N.R. Nichay, I.Yu. Zhuravleva, Yu.Yu. Kulyabin, I.S. Zykov, E.V. Boyarkin, O.Yu. Malakhova, T.P. Timchenko, Ya.L. Rusakova, I.S. Murashov, A.A. DokuchaevaCritical revision of the article: N.R. Nichay, I.Yu. Zhuravleva, Yu.Yu. Kulyabin, A.A. Dokuchaeva, A.V. Bogachev-ProkophievFinal approval of the version to be published: N.R. Nichay, I.Yu. Zhuravleva, Yu.Yu. Kulyabin, I.S. Zykov, E.V. Boyarkin, O.Yu. Malakhova, E.V. Kuznetsova, T.P. Timchenko, Ya.L. Rusakova, I.S. Murashov, A.A. Dokuchaeva, A.V. Bogachev-Prokophiev

Recurrent Foreign Body Reactions to Neuroendovascular Polymers—A Clinicopathologic Case Study

Objective We provide histopathologic and neuroimaging evidence of recurrent foreign body reactions in a patient following separate stent-assisted coiling of two contralateral intracranial aneurysms a decade apart. Background Stent-assisted endovascular coiling for wide-neck cerebral aneurysms introduces permanent foreign materials into the cerebral vasculature. While foreign body reactions after endovascular coiling are increasingly reported in the literature, compelling histopathologic data remains very limited. Design/Methods Electronic medical record review for clinical details and neuroimaging. Histopathology was extensively reviewed with a neuropathologist. Results A 37-year-old woman presents with left arm weakness. Magnetic resonance imaging (MRI) shows numerous enhancing lesions with large multifocal T2 FLAIR changes in the right hemisphere. An extensive vascular, infectious, autoimmune, and neoplastic workup returns negative. Months earlier, she had undergone stent-assisted coiling of a right internal carotid artery (ICA) aneurysm. A decade prior, she had presented with focal right-sided seizures after coiling of a left ICA aneurysm; MRI brain at the time revealed two enhancing lesions in the left hemisphere of unclear etiology. A brain biopsy is performed, and histopathology reveals multifocal, chronic micro-abscesses characterized by collections of neutrophils surrounded by a rim of multinucleated giant cells and histiocytes which are in turn rimmed by fibrosis and granulation tissue. Staining is negative for neoplastic changes and infectious organisms. Rare filamentous structures are identified in association with the giant cells; these resemble coil polymers described in the endovascular literature and are highly suspicious for inducing a neuroinflammatory foreign body reaction. She improves following glucocorticoid treatment, and repeat imaging shows substantial reduction in parenchymal abnormalities. Conclusions Foreign body reactions are an uncommon complication of endovascular aneurysm coiling and can manifest as an embolic inflammatory phenomenon. These neuroinflammatory reactions are driven by endovascular polymers and responsive to glucocorticoid treatment. Heightened awareness can facilitate earlier diagnosis and treatment, with prompt neuroimmunology consultation for repeat endovascular procedures.

P221 Deep dermatophytosis presented as multiple exophytic masses caused by Trichophyton rubrum in immunocompromised patient with rheumatoid arthritis; a case report

Poster session 2, September 22, 2022, 12:30 PM - 1:30 PM Dermatophyte invades the stratum corneum and infects the skin, nails, and hair, mostly resulting in superficial infection. Deep dermatophytosis involving dermis and subcutaneous layer was rarely reported in immunocompromised state. Herein, we report a case with deep dermatophytosis caused by Trichophyton (T.) rubrum. A 71-year-old woman presented with multiple erythematous exophytic and subcutaneous nodules located on both lower legs. She was taking immunosuppressive agents for rheumatoid arthritis and had taken antifungal agents for tinea pedis and onychomycosis, which was improperly ceased. Histopathologic examination revealed pseudoepitheliomatous epidermal hyperplasia with microabscess formation in epidermis and diffuse granulomatous inflammation consisting of multinucleated giant cells, lymphocytes, neutrophils, and histiocytes in dermis. Imuunohistochemical staining with periodic acid-schiff (PAS) and Gomori methenamine silver (GMS) showed septate and branched fungal hyphae in dermis. Trichophyton rubrum was identified in fungal culture with tissue and confirmed through phylogenetic analysis of internal transcribed spacer (ITS) and large subunit regions (LSU) in ribosomal RNA. Prior to identification of causative organism, her condition deteriorated into septic shock. Amphotericin B was administered empirically for 6 days in order to prevent hematogenous dissemination and skin lesions were simultaneously resolved. Since deep dermatophytosis appears in various clinical manifestations, it is easy to be mistaken for another disease. If treatment is delayed, immunocompetent patients can progress to severe disease courses like hematogenous dissemination, so clinicians should differentiate this disease and conduct treatment at an appropriate time.

Solitary Conjunctival Reticulohistiocytoma

A 31-year-old healthy man presented with a circumscribed “salmon-colored” forniceal conjunctival nodule (Fig A). Pathology revealed a subepithelial circumscribed infiltrate (Fig B, hematoxylin-eosin, 100×) comprising mononuclear and multinucleated histiocytes with large ovoid eccentric nuclei, prominent nucleoli, and abundant finely granular, “ground glass-like” eosinophilic cytoplasm in a background of lymphocytes (Fig C, hematoxylin-eosin, 400×). The histiocytes were CD163-positive and S100-negative.

Disseminated Phaeohyphomycotic Lymphadenitis with Cladophialophora Species

Objective: This study describes a case of disseminated phaeohyphomycotic lymphadenitis in a young female with delayed diagnosis and good clinical response after appropriate treatment. Methods: A 32-year-old female presented with erythematous to violaceous papules with oozing discharge bilaterally in her inguinal region for a few months. History revealed tuberculous meningitis 4 years earlier treated with first line anti-tuberculous therapy for 18 months, and 2 years previously she developed pigmented discharging lymph nodes bilaterally in her axillae. The histopathology of the biopsy of the axillary nodes showed chronic granulomatous inflammation with multiple branching septate fungal hyphae. She received amphotericin B for 21 days but without improvement. Biopsy from the inguinal lesions was sent for histopathology and culture. Results: Histopathology of the biopsy material showed chronic granulomatous inflammatory process with multinucleate giant cells, epithelioid cells, histiocytes, and lymphocytes with multiple branching septate fungal hyphae. Gram stain revealed moderate septate hyphae with numerous pus cells. Culture on Sabouraud dextrose agar yielded velvety olive–black colonies in the fourth week. Microscopic slide examination of culture material was suggestive of Cladophialophora species. The patient was started on voriconazole, which was continued for 6 months, and showed clinical improvement. Conclusion: Incomplete investigation of infectious lesions may delay diagnosis. Furthermore, clinical presentations are greatly influenced by the immune status of the host. Both histopathological and microbiological assessments are equally important for making a conclusive diagnosis. Anti-fungal therapy may delay the growth of fungi that normally grow within a week; thus, a longer incubation time may be warranted for fungal smear-positive samples.

Mycobacterium chimaera: a report of 2 new cases and literature review

Mycobacterium chimaera is a non-tuberculous mycobacterium, member of the Mycobacterium avium complex (MAC), which has become a global public health concern due to infection following cardiac surgery performed with contaminated heater-cooler units. M. chimaera infection is characterized by a long latency, non-specific signs and symptoms and high mortality rates. Thus, the diagnosis is still challenging both for forensic pathologists and for clinicians. Clinical manifestations of M. chimaera infection include endocarditis, hepatitis, nephritis, encephalitis and chorioretinitis. A constant histopathologic finding is the presence of non-caseating granulomas, with multinucleated giant cells and histiocytes. Hereby, we present two cases of fatal disseminated M. chimaera infection following aortic valve surgery reporting clinical history and post-mortem findings. Further, we provide a brief overview of the literature with a special focus on histopathological characteristics of M. chimaera infection. The aim of this article is to provide a complete synopsis of histopathological characteristics useful for forensic pathologists.

Morphological features of pilonidal cysts of the sacrococcygeal region.

Despite the fact that the pilonidal cyst of the sacrococcygeal region is a long-known disease, the mechanism of accumulation or absence of hair in the cyst remains unclear, which affects the accuracy of the name of the disease, as well as understanding of its pathogenesis. Aim to perform morphological examination of pilonidal cysts of the sacrococcygeal region, to determine the nature of the cysts, the frequency of hair in the cyst cavity and to determine the causes and mechanism of its accumulation in cysts. A morphological study of skin areas with altered tissues of the sacrococcygeal region after radical surgical treatment of 235 patients with a coccygeal cyst of the sacrococcygeal region was carried out. The gender distribution of patients with pilonidal cysts was as follows: 220 (93.4%) male patients, 15 female patients (6.6%). Among 235 patients who underwent radical surgical treatment, the absence of hair shafts was recorded in 112 (46.8%) cases, hair in the cyst structure - in 123 male patients (53.2%), both visually and under a microscope, and in 4 of them (0.9%) only under a microscope. Among 15 patients, hair in the cyst cavity was found in 1 case (0.4%), in 14 patients they were not detected either visually or by microscopic examination. Having observed the formation of foreign body granuloma and the accumulation of polynuclear histiocytes of foreign bodies around the hair in the pilonidal cyst cavity, a proportional increase in histiocytes depending on the number of hairs, that is, the body's reaction to the foreign body was registered. However, multinucleated histiocytes in lower numbers were also observed in cases in which hair shafts were not found either microscopically or macroscopically, which may indicate both completed phagocytosis and formation of a cyst without a hair component, registering the reaction of histiocytes to inflammatory changes in the cyst cavity. The detection of atypically located pilonidal cysts (cheek, navel) provides additional confirmation of the formation of pilonidal cyst as a result of disturbance of hair growth through the hair funnel due to inflammatory changes in the hair follicle and their accumulation subcutaneously.

Long-term effects of uterine artery embolization caused by the embolic material

Background and objectives. Uterine artery embolization (UAE), or uterine fibroid embolization (EFM), a technique introduced in the conservative treatment of uterine fibroids in the 1990s, has been increasingly used in the last decades. The data accumulated in time revealed also, besides the expected benefits, some undesirable complications, initially unanticipated. The study aims at analyzing the histological changes of myometrium occurred after uterine artery embolization for fibroids. Materials and method. Presentation of a series of three cases that have undergone gynecologic surgery in the Bucur Maternity of the “Sf. Ioan” Emergency Clinical Hospital, Bucharest, after the embolization of the uterine arteries performed (in the past) for fibroids. Results. In two of the three cases presented, it was practiced hysterectomy with bilateral anexectomy and in one case myometrectomy. At the histopathological examination, what was proven to be specific for the long-term effects of UAE was the thickening of vascular structures containing intraluminal amorphous material, with vascular and perivascular infiltration with giant multinucleated histiocytes around the foreign body. This histological aspect corresponds to a nonspecific granulomatous inflammation with giant cells. Conclusions. Embolization of the uterine arteries may cause a giant-cell type inflammation at the level of the myometrium and fibrosis, and this type of changes could be the cause of a poor prognosis for women who want a future pregnancy.

S2405 Post-Infantile Giant Cell Hepatitis

INTRODUCTION: Post-infantile giant cell hepatitis (PIGCH) is a rare disorder among adults. Diagnosis is dependent on liver biopsy and its histologic hallmark is the presence of hepatocyte-derived multinucleated giant cells. This is thought to be due to increased hepatocyte regenerative activity that occurs as a response to noxious stimuli including viral infections, autoimmune disorders, leukemia and drug reactions. We report two cases of PIGCH including its management and outcome. CASE DESCRIPTION/METHODS: Case 1 is a 62-year-old African American male who presented with jaundice, dark urine and generalized malaise. Past medical history notable for alcohol use disorder in remission and chronic hepatitis C treated with antiviral therapy. Physical examination revealed jaundice. Bloodwork included ALT 2,300 U/L, AST 1,900 U/L, ALP 186 U/L, GGT 177 U/L, serum total bilirubin 29 mg/dL, direct bilirubin 20 mg/dL, AFP level 25 μg/L and INR 1.5. Infectious work up was negative and abdominal ultrasound was normal. Autoimmune markers ANA, SMA and AMA were positive. Liver biopsy showed severe syncytial giant cell hepatitis with 75% loss of hepatocytes. Patient was started on steroids with complete normalization of his transaminases on four month follow up. Case 2 is a 69-year-old Caucasian male with history of dyslipidemia, hypertension and chronic lymphocytic leukemia (CLL) on Ibrutinib, who presented with generalized malaise. He denied any alcohol, tobacco, or substance use. Physical examination revealed jaundice. Bloodwork included AST 2,385 U/L, ALT 5,609 U/L, ALP 286 U/L, total bilirubin 31.3 mg/dL, direct bilirubin 23.6 mg/dL and INR was 1.1. Infectious and autoimmune work up was negative. Abdominal ultrasound was normal. Liver biopsy showed syncytial giant cell hepatitis with CLL infiltrates on most portal tracks. Patient was started on steroids with temporary normalization of transaminases. Unfortunately, one week later, the patient died due to cancer-related complications. DISCUSSION: PIGCH has been commonly associated with autoimmune hepatitis but only a few case reports of CLL-associated PIGCH exist. Given its heterogeneous etiologies, PIGCH is difficult to prognosticate and manage. However, it should be considered in all patients with acute liver injury or chronic liver disease of unknown disease. Despite having a good response to immunosuppressive therapy, patients may still develop severe progressive disease requiring liver transplantation. Hence, prompt recognition and treatment is crucial.Figure 1.: The multinucleated giant cell hepatocytes (see arrows) are seen in H&E stained sections of biopsy. These are reactively altered hepatocytes (rather than multinucleated giant cell histiocytes). Immunoperoxidase stains show (see inset images) that within multinucleated hepatocytes, nuclei are strongly positive for Cyclin-D1 and cytoplasm is strongly positive for cytokeratin CK8/CK18 (Cam5.2).Figure 2.: In Case 2, the same stains were used as in Case 1 however the portal tract contains an infiltrate of neoplastic lymphoid cells (CLL).

Infiltration of Lymphocytes and Mast Cells to Bladder Tissues in Experimental Models of Interstitial Cystitis/Bladder Pain Syndrome

Background: A different degree of severity of inflammation was detected in the bladder biopsy specimens; however, the cellular mechanisms of inflammation in interstitial cystitis/bladder pain syndrome (IC/BPS) and the processes leading to tissue damage and fibrosis are not yet completely clear. Objectives: The aim of this study was to determine the leukocyte and mast cell infiltration to the bladder tissue in various experimental models of IC/BPS. Methods: Various IC/BPS models have been generated using white New Zealand rabbits. Animals were divided into 4 groups depending on the type of the model: (1) The introduction of 0.5% HCl into the bladder; (2) The introduction of urine taken from the bladder into the wall of the bladder; (3) The introduction of 0.9% NaCl; (4) Intact animals. The number of cells in the tissues of the bladder was evaluated in points and histological analysis of the tissues of the bladder wall was performed. The analysis was carried out after 14 days of modeling. Results: Mast cells were determined only in groups 1 and 2 (P < 0.001). In the 2nd group, developing necrosis and mixed inflammatory infiltration, giant, necrotic, multinucleated histiocytes were noted. In group 3, tissue edema and single scattered lymphocytes were noted. Conclusions: The association of high inflammatory cell infiltration in the chemical version of the IC/BPS model and mast cell infiltration with impaired bladder integrity has been established.

Cytomorphological features of cystic neutrophilic granulomatous mastitis on ThinPrep.

Granulomatous mastitis (GM) is an uncommon entity and challenging to distinguish from breast carcinoma, both clinically and upon imaging. Cystic neutrophilic granulomatous mastitis (CNGM) is a histologically distinct GM with clear "cystic" spaces (CS) surrounded by neutrophils and may contain Gram-positive bacilli (such as Corynebacterium species). Cytologic features of GM, in particular CNGM, on ThinPrep (TP), are limited. We reviewed the cytological features of GM with a special focus on CNGM on TP. Ten cases with a concurrent/recent FNA and histologic diagnosis of GM or CNGM, or positive culture for Corynebacterium kroppenstedtii, were identified over an 11-y period (2007-2017). A double-blinded review of the TP slides was performed by two independent cytopathologists. Data were analysed using Fisher's exact test. Six cases were histologically proven CNGM and 1 FNA only case had a positive culture for C. kroppenstedtii. Three had a histological diagnosis of GM. TP from the 7 CNGM cases demonstrated CS, including 1 case with a cellblock (CB) study showing well-formed clear CS, while none of the non-CNGM cases had CS (P = .01). Bacteria were identified within CS in 5 of 7 cases of CNGM. Multinucleated giant cells, granulomas, histiocytes, and neutrophils were variably observed. All histologically confirmed cases of CNGM showed distinct CS on TP. Cellblock study is a valuable adjunct to evaluate CNGM and for ancillary studies. Although our study was limited by a small sample size, our findings necessitate the need for studies with a larger cohort.