Evidence Suggesting a Role of Iron in a Mouse Model of Nephrogenic Systemic Fibrosis.

Nephrogenic systemic fibrosis is associated with gadolinium contrast exposure in patients with reduced kidney function and carries high morbidity and mortality. We have previously demonstrated that gadolinium contrast agents induce in vivo systemic iron mobilization and in vitro differentiation of peripheral blood mononuclear cells into ferroportin (iron exporter)-expressing fibrocytic cells. In the present study we examined the role of iron in a mouse model of nephrogenic systemic fibrosis. Chronic kidney disease was induced in 8-week-old male Balb/C mice with a two-step 5/6 nephrectomy surgery. Five groups of mice were studied: control (n = 5), sham surgery control (n = 5), chronic kidney disease control (n = 4), chronic kidney disease injected with 0.5 mmol/kg body weight of Omniscan 3 days per week, for a total of 10 injections (n = 8), and chronic kidney disease with Omniscan plus deferiprone, 125 mg/kg, in drinking water (n = 9). Deferiprone was continued for 16 weeks until the end of the experiment. Mice with chronic kidney disease injected with Omniscan developed skin changes characteristic of nephrogenic systemic fibrosis including hair loss, reddening, ulceration, and skin tightening by 10 to 16 weeks. Histopathological sections demonstrated dermal fibrosis with increased skin thickness (0.25±0.06 mm, sham; 0.34±+0.3 mm, Omniscan-injected). Additionally, we observed an increase in tissue infiltration of ferroportin-expressing, fibrocyte-like cells accompanied by tissue iron accumulation in the skin of the Omniscan-treated mice. The deferiprone-treated group had significantly decreased skin thickness (p<0.05) and significantly decreased dermal fibrosis compared to the Omniscan-only group. In addition, iron chelation prevented tissue infiltration of ferroportin-expressing, fibrocyte-like cells. Our in vitro experiments demonstrated that exposure to Omniscan resulted in the release of catalytic iron and this was prevented by the iron chelator deferiprone. Deferiprone inhibited the differentiation of human peripheral blood mononuclear cells into ferroportin-expressing cells by immunohistochemical staining and western blot analysis. Our studies support an important role of iron in the pathophysiology of gadolinium chelate toxicity and nephrogenic systemic fibrosis.

Recurrent status epilepticus as the primary neurological manifestation of CADASIL: A case report.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) often presents with a history of migraine with aura and eventual manifestations of dementia with unrelenting, repeated cerebral vascular insults. Only 6-10% of patients with CADASIL have been reported to develop seizures, and status epilepticus (SE) is exceedingly rare. Here, we describe a patient who presented with recurrent SE, with eventual biopsy diagnosis of CADASIL. An 80-year-old woman presented to our hospital three times in two years with decreased level of consciousness and subtle intermittent right-sided upper extremity and facial twitching. There was no known significant family history and no past medical history for seizures, stroke, migraine headache, or overt dementia. Electroencephalography revealed recurrent focal seizures with left hemispheric onset and evolution, fulfilling the criteria for focal SE each time. All three admissions required sedation with midazolam to control seizure activity, in addition to high doses of multiple antiepileptic drugs. Brain MRI repeatedly showed extensive abnormalities in the periventricular and deep white matter, subcortical white matter, and bilateral basal ganglia. Skin biopsy was obtained on the third admission, and electron microscopy showed numerous deposits of granular osmiophilic material, which are pathognomonic for CADASIL. Detailed investigations failed to reveal any other etiology for the patient's condition. This case illustrates the potential for nonconvulsive SE to be the sole manifestation of CADASIL. With the appropriate brain MRI findings, CADASIL should be added to the list of rare causes of SE.

Cutaneous ciliated cyst of the scalp: a case report of a cutaneous ciliated eccrine cyst and a brief review of the literature.

Cutaneous ciliated cysts (CCC) are rare benign cysts known to occur in the lower extremities of females of reproductive age. Currently, there are 2 theories that attempt to explain the histogenesis of this rare entity. The theory of Mullerian heterotopia provides a plausible histogenetic explanation for the vast majority of CCC. A proposed alternative theory is the ciliated metaplasia of eccrine glands. We believe that previously reported cases of CCC include 2 distinct entities. We report, herein, the first case reported in the literature of a cutaneous ciliated eccrine cyst occurring on the scalp.

Gadolinium contrast agent-induced CD163+ ferroportin+ osteogenic cells in nephrogenic systemic fibrosis.

Gadolinium-based contrast agents are linked to nephrogenic systemic fibrosis in patients with renal insufficiency. The pathology of nephrogenic systemic fibrosis is characterized by abnormal tissue repair: fibrosis and ectopic ossification. The mechanisms by which gadolinium could induce fibrosis and ossification are not known. We examined in vitro the effect of a gadolinium-based contrast agent on human peripheral blood mononuclear cells for phenotype and function relevant to the pathology of nephrogenic systemic fibrosis using immunofluorescence, flow cytometry, real-time PCR, and osteogenic assays. We also examined tissues from patients with nephrogenic systemic fibrosis, using IHC to identify the presence of cells with phenotype induced by gadolinium. Gadolinium contrast induced differentiation of human peripheral blood mononuclear cells into a unique cellular phenotype--CD163(+) cells expressing proteins involved in fibrosis and bone formation. These cells express fibroblast growth factor (FGF)23, osteoblast transcription factors Runt-related transcription factor 2, and osterix, and show an osteogenic phenotype in in vitro assays. We show in vivo the presence of CD163(+)/procollagen-1(+)/osteocalcin(+) cells in the fibrotic and calcified tissues of nephrogenic systemic fibrosis patients. Gadolinium contrast-induced CD163(+)/ferroportin(+)/FGF23(+) cells with osteogenic potential may play a role in systemic fibrosis and ectopic ossification in nephrogenic systemic fibrosis.

Expression of PTEN in mycosis fungoides and correlation with loss of heterozygosity.

BACKGROUND: Mycosis fungoides (MF) exhibits a variety of underlying molecular defects including aberrations involving the PTEN tumor suppressor gene. Specifically, loss of heterozygosity of PTEN has been previously demonstrated. We hypothesize that abnormalities of PTEN may result in altered immunohistochemical expression of its protein product. METHODS: Thirty-six MF specimens were stained with monoclonal antibody against PTEN protein. The percentage of nuclei retaining PTEN expression and the staining intensity was recorded. RESULTS: Average percentage of lymphoma cells retaining expression of the PTEN protein was 92% within patch-stage lesions, 81.4% in plaque-stage lesions, and 81.1% in tumor-stage lesions. Average intensity of staining for patch-stage lesions was 2.90, 2.50 for plaque lesions and 2.44 for tumor lesions. Cases lacking loss of heterozygozity at PTEN (n = 6) had an average expression of 81% and an average intensity of staining of 2.42. Whereas, cases with loss of heterozygozity at PTEN (n = 6) had an average expression of 75% of cells with an average staining intensity of 2.33. CONCLUSIONS: The percentage of cells retaining PTEN and staining intensity decrease from patch- to plaque-stage lesions, whereas both parameters show mild diminution in tumor lesions compared with plaque lesions. PTEN expression in a small sample seems to correlate with previous demonstration of loss of heterozygosity at the molecular level. Although a trend for loss of PTEN expression exists with histologic progression of MF, the effect is modest and may not represent the pivotal defect in MF pathogenesis.

The spectrum of histopathologic findings in cutaneous eruptions associated with influenza A (H1N1) infection.

Influenza A (H1N1), like many other viral infections, has been associated with cutaneous eruptions. Differential diagnoses in a viral exanthem generally include spongiotic dermatitis, urticaria and drug reaction. The aim of this series was to retrospectively review three cases (five biopsies) involving patients with a clinical history of H1N1 and an accompanying rash, and to evaluate whether unique histopathologic and immunohistochemical features exist among these patients' cutaneous eruptions. Findings among all cases included a sparse superficial perivascular infiltrate, and interestingly, scattered interstitial and prominent intravascular neutrophils. Two cases demonstrated mild spongiosis and mild interface change. Immunohistochemistry in all cases revealed a CD4-predominant lymphocytic infiltrate of the dermis with a sparse intraepidermal population of admixed CD4 and CD8 positive lymphocytes. Many changes found in the cutaneous eruption associated with H1N1 are similar to those of other viral eruptions, including a mild perivascular lymphocytic infiltrate, mild spongiosis and mild interface change; however, sparse dermal and intravascular neutrophils and intraepidermal lymphocytes appear to be the features unique to these cases of H1N1-associated cutaneous eruptions. Such a distinction may prove diagnostically important in the clinical setting and useful in the surveillance of this historically pandemic virus.

Misregulation of Rad50 expression in melanoma cells.

DNA double-strand breaks are increased in human melanoma tissue as detected by histone H2AX phosphorylation.(1-3) We investigated two of the downstream effectors of DNA double-strand breaks, Rad50 and 53BP1 (tumor suppressor p53 binding protein 1), to determine if they are altered in human primary melanoma cells. Melanoma cases showed high Rad50 staining (81.8%; 9/11) significantly more frequently than conventional or atypical melanocytic nevi (0%; 0/18). In contrast, the staining pattern for 53BP1 appears similar between melanoma and nevi. This is the first study that shows activation and misregulation of the DNA repair pathway in human melanoma cells. The staining features of Rad50, a component of an essential DNA double-strand break repair complex, are clearly increased in melanoma cells with regards to both staining intensity and the number of positive melanoma cells. Interestingly, among the melanoma cases with increased Rad50 staining, most demonstrated cytoplasmic rather than nuclear staining (88.9%, 8/9). Further studies are needed to determine the cause of this mislocalization and its affects, if any, on DNA double-strand break repair in melanoma.

Collapsing angiokeloidal dermatofibroma.

A heterogeneous group of benign fibrohistiocytic lesions has been assembled under the umbrella term, dermatofibroma. These lesions share a morphology of bland spindled cells encompassed by and intercalating through thick dermal collagen; unique variants have been described based on secondary histologic features, some of which include aneurysmal, myxoid, lipidized, signet ring, angiomatous, and keloidal. Here, we present a distinct dermatofibroma variant henceforth known as collapsing angiokeloidal dermatofibroma identified in 2 patients with slowly growing nodules of the buttock and the arm. Microscopically, the lesions have a characteristic dermatofibroma appearance but are accompanied by unusual diffuse small caliber vessels whose walls are collapsed by a thick, eosinophilic, keloid-like substance. The eosinophilic material resembles the adjacent dermal collagen; however, it does not stain for type-4 collagen or type-1 procollagen, amyloid, or glycogen. Although the exact composition of the keloidal material remains ambiguous, the architectural novelty of collapsing angiokeloidal dermatofibroma serves to further expand the morphologic spectrum of benign fibrous histiocytomas, although highlighting the difficulty in distinguishing between it and similar lesions.

A case of cutaneous Scedosporium infection in an immunocompromised patient.

Scedosporium apiospermum, the asexual stage of Pseudoallescheria boydii, is a fungus ubiquitous in soil as well as organically polluted areas, where nitrogen-containing compounds are abundant. It is an emerging opportunistic pathogen that can range from cutaneous to disseminated infection and can be fatal within months of diagnosis. Here we present a case of disseminated S. apiospermum infection with cutaneous manifestations in a 59-year-old woman with myelodysplastic syndrome, in remission from chronic lymphocytic leukemia, presented with pneumonia and deteriorating mental status. An X-ray computed tomography scan showed three non-contrast-enhancing hypodensities affecting the brain. Many erythematous, indurated skin lesions, measuring 3-5 mm in diameter, were noted on her chest, shoulders and arms. Biopsies were submitted for culture and histology. Histopathologic examination revealed superficial and deep perivascular and periadnexal inflammatory infiltrates of lymphocytes and neutrophils. Scattered collections of fungal organisms were noted near the eccrine glands. The periodic acid Schiff with diastase stain showed the presence of variable sized spores and hyphae with some acute angle branching. Both tissue and blood cultures were positive for a single Scedosporium species. Histologically, eccrine or peri-eccrine involvement by fungi may be an important finding for Scedosporium infection of the skin.

A rapidly progressing Pancoast syndrome due to pulmonary mucormycosis: a case report.

INTRODUCTION: Pancoast syndrome is characterized by Horner syndrome, shoulder pain radiating down the arm, compression of the brachial blood vessels, and, in long-standing cases, atrophy of the arm and hand muscles. It is most commonly associated with lung carcinoma but rarely is seen with certain infections. CASE PRESENTATION: We present the case of a 51-year-old Caucasian man who had acute myeloid leukemia and who developed a rapidly fulminating pneumonia along with signs and symptoms of acute brachial plexopathy and left Horner syndrome. Also, a purpuric plaque developed over his left chest wall and progressed to skin necrosis. The skin biopsy and bronchoalveolar lavage showed a Rhizopus species, leading to a diagnosis of mucormycosis. This is a rare case of pneumonia due to mucormycosis associated with acute Pancoast syndrome. CONCLUSIONS: According to our review of the literature, only a few infectious agents have been reported to be associated with Pancoast syndrome. We found only three case reports of mucormycosis associated with acute Pancoast syndrome. Clinicians should consider mucormycosis in their differential diagnosis in a patient with pulmonary lesions and chest wall invasion with or without neurological symptoms, especially in the setting of neutropenia or other immunosuppressed conditions. It is important to recognize this condition early in order to target therapy and interventions.

Association between natural killer cells and regression in melanocytic lesions.

Mortality from melanoma, the deadliest of skin cancers, continues to increase in all age groups. A small number of melanomas spontaneously regress. In vitro studies suggest a role for the natural killer cell in effecting regression. In this study, the goal was to determine if natural killer cells are preferentially involved in the cytotoxic response in regressing lesions. Forty-two cases were selected: nevi with regression, nonregressing melanoma with brisk inflammation, and regressing melanoma. Sections were stained with hematoxylin and eosin and immunostained for CD8, CD56, and T-cell intracytoplasmic antigen 1. Numbers of total lymphocytes, CD8-positive lymphocytes, and T-cell intracytoplasmic antigen 1-positive lymphocytes did not differ among the 3 populations or based on location. CD56 positivity was significantly different among the 3 populations. Regressing melanomas showed the greatest CD56 activity, followed by regressing nevi, whereas inflamed, nonregressing melanomas showed the least. CD56(+) lymphocytes were mostly counted in areas of early regression. The natural killer cell could plausibly play a role in the occurrence of regression as a cytotoxic effector cell or as a mediator of the cytotoxic mechanism.

Intraoperative sentinel lymph node analysis in melanoma.

BACKGROUND: The objective of this retrospective cohort study was to evaluate the sensitivity and specificity of touch preparation cytology (TPC) and frozen section (FS) histology in the intraoperative staging of melanoma. METHODS: The cohort was identified from all patients with clinically node negative melanoma undergoing a SLN biopsy using Technetium and/or blue dye mapping from 1/1998 to 10/2008. TPC and FS analysis was performed utilizing Diff-quick and compared to permanent section interpretation with H&E. RESULTS: Of 271 patients undergoing SLN biopsy, 163 underwent intraoperative analysis of the sentinel node (125 underwent TPC alone, 15 underwent FS alone, 23 underwent both TPC and FS), and 108 underwent no intraoperative analysis. Thirty-three patients undergoing intraoperative analysis of the SLN were found to have positive nodes (20%) on permanent histology. There were no false positives identified (specificity = 100%). The overall sensitivity for all methods of intraoperative analysis was 61% (20/33). On a per patient basis, the sensitivity was 47% (9/19) for TPC alone, 75% (3/4) for FS alone, and 80% (8/10) for both TPC and FS. CONCLUSIONS: There were no false positives identified suggesting TPC and FS can be used safely to identify the majority of SLN that harbor metastases from melanoma.

Concordance of frozen and permanent sections for the diagnosis of skin lesions.

BACKGROUND: There has been little written concerning the use of frozen sections to diagnose skin lesions. OBJECTIVE: To compare the concordance between frozen and permanent sections of the same diagnostic skin biopsy specimen. METHODS AND MATERIALS: Over 3 months, all non-melanocytic skin lesions that were biopsied in a skin cancer clinic were examined using frozen and permanent sections. Diagnoses from a dermatologist and dermatopathologist were recorded for each specimen and later examined for concordance. RESULTS: There was rare (0.5% of specimens) disagreement recorded between interpretations of the dermatologist and dermatopathologist. Permanent and frozen section pathology agreed with one another 90.4% of the time. Specimen processing was the most probable cause of discordance. Most discordance was not clinically relevant, although the patient was clinically affected in 35 of 2009 specimens (1.7%). CONCLUSION: Although there is a high concordance rate between diagnostic frozen and permanent sections, there are significant quality assurance and patient care advantages to following up initial diagnostic frozen sections with permanent sections of the same specimen.

Rapid improvement of nephrogenic systemic fibrosis with rapamycin therapy: possible role of phospho-70-ribosomal-S6 kinase.

Nephrogenic systemic fibrosis (NSF) is a fibrosing disorder that occurs in some patients with renal insufficiency. Exposure to gadolinium-based contrast agents (GdCA) has been associated with the development of NSF. No uniformly effective treatment options exist. We present immunohistochemical evidence to show that the proliferating fibrocytes of NSF express phospho-70-s6 kinase (PI-3-K), a protein downstream of PI-3-K, and the target of the drug rapamycin. In our patient, use of rapamycin resulted in rapid clinical improvement marked by reduced edema, reduced skin induration, and decreased pain. This suggests a possible role for PI-3-K and rapamycin (mTOR) pathways in the pathogenesis of NSF. Drugs that inhibit these pathways may be a target for future therapy. While our patient did attribute disease onset to GdCA exposure, used on a single occasion for abdominal imaging, he was also exposed to iron, calcium, and darbepoetin alpha at the time of imaging.

Utility of p63 in the differential diagnosis of atypical fibroxanthoma and spindle cell squamous cell carcinoma.

Atypical fibroxanthoma (AFX), spindle cell squamous cell carcinoma (SCSCC) and spindle cell melanoma are the primary entities in the differential diagnosis of a cytologically atypical spindle cell tumor arising on sun-damaged skin. AFX is generally regarded as a diagnosis of exclusion in this context: in the absence of S100 or keratin reactivity, a diagnosis of AFX is favored. However, keratin reactivity may be focal or even absent in SCSCC, and although numerous positive markers of AFX have been proposed, none has shown sufficient sensitivity and specificity for routine diagnostic use. We evaluated 20 AFX and 10 SCSCC with a panel of cytokeratins and p63 to assess the utility of the latter antibody in this differential diagnosis. All 10 SCSCC showed strong expression of p63, whereas all 20 AFX were p63 negative. Two additional cases (excluded from the study) were negative for keratins and S100 on initial shave biopsies, resulting in a favored diagnosis of AFX, but p63 stains performed retrospectively were positive. However, review of the excision specimens in both cases revealed deep subcutaneous extension, excluding AFX. p63 reactivity argues against the diagnosis of AFX and is therefore a useful addition to the standard immunohistochemical panel for cutaneous spindle cell neoplasms.

Metal deposition in calcific uremic arteriolopathy.

BACKGROUND: Calcific uremic arteriolopathy (CUA) is an often fatal disease that affects patients with end-stage renal disease. Although animal studies support a role for metals in the pathogenesis of CUA, metal accumulation in human tissue has not been previously evaluated. OBJECTIVE: We sought to evaluate metal deposition in CUA. METHODS: Twelve histologically proven cases of CUA were identified from our dermatopathology database. Five skin biopsy specimens from patients with chronic kidney disease exposed to gadolinium contrast but without CUA were used as controls. Quantification of metals including iron, aluminum, and gadolinium in the lesional skin was performed using inductively coupled mass spectrometry. RESULTS: Seven patients had documented exposure to gadolinium-based contrast in the 2 years before CUA. Three of them had concurrent nephrogenic systemic fibrosis. Highly significant quantities of iron (P = .03) and aluminum (P = .0002) were detected in CUA specimens compared with controls. Significant amounts of gadolinium were present in several CUA biopsy specimens. LIMITATIONS: Observational, retrospective study design and small sample size are limitations. CONCLUSION: Tissue iron and aluminum content is increased in CUA. A significant amount of gadolinium is also present in some CUA specimens. Based on animal studies that strongly implicate metals in the pathogenesis of CUA, our data suggest that metal deposition should be considered in the pathogenesis of human CUA.