Pilomatrixcarcinoma of the Foot: A New Localization of an Extremely Rare Adnexal Tumour

Pilomatrixcarcinoma is a very rare follicular neoplasm that shows matrical differentiation. The majority of these lesions originate de novo, while only a few cases of transformation of pilomatricoma (calcifying epithelioma of Malherbe) have been described in the literature. The neoplasm affects mostly middle-aged males with a male-to-female ratio of 3–4:1. The most common localizations are the face, head, trunk and extremites, though there are a few reports of pilomatrixcarcinoma of the eyelid, eyebrow, axilla and clitorid. Here, we describe the first case of a pilomatrixcarcinoma on the anterolateral surface of the first toe of the left foot of an 83-year-old patient, which developed in less than six months and led to amputation of the distal phalanx. We report a brief review of the current literature with particular emphasis on histopathological features useful for diagnosis

Sonographic and Power Doppler Evaluation of an Invasive Mole Located in a Cesarean Scar Pregnancy.

We report on the sonographic evaluation, clinical management, and pathologic characteristics of an unusual case of a partial molar cesarean scar pregnancy that evolved into an invasive mole. Initially, this pregnancy was misdiagnosed as a simple cesarean scar pregnancy. After treatment with local and systemic methotrexate (MTX), 2‐dimensional sonography and a power Doppler evaluation together with serum β‐human chorionic gonadotropin (β‐hCG) test results were suggestive of a molar pregnancy; a complementary 3‐dimensional (3D) sonographic evaluation was also performed to better identify and localize the blood supply to the cesarean scar pregnancy and to measure the volume of the ectopic mass. To our knowledge, the sonographic features of this entity have not been reported previously

Thiostrepton, a resurging drug inhibiting the stringent response to counteract antibiotic-resistance and expression of virulence determinants in Neisseria gonorrhoeae

: Due to the increased resistance to all available antibiotics and the lack of vaccines, Neisseria gonorrhoeae (the gonococcus) poses an urgent threat. Although the mechanisms of virulence and antibiotic resistance have been largely investigated in this bacterium, very few studies have addressed the stringent response (SR) that in pathogenic bacteria controls the expression of genes involved in host-pathogen interaction and tolerance and persistence toward antibiotics. In this study, the results of the transcriptome analysis of a clinical isolate of N. gonorrhoeae, after induction of the SR by serine hydroxamate, provided us with an accurate list of genes that are transcriptionally modulated during the SR. The list includes genes associated with metabolism, cellular machine functions, host-pathogen interaction, genome plasticity, and antibiotic tolerance and persistence. Moreover, we found that the artificial induction of the SR in N. gonorrhoeae by serine hydroxamate is prevented by thiostrepton, a thiopeptide antibiotic that is known to interact with ribosomal protein L11, thereby inhibiting functions of EF-Tu and EF-G, and binding of pppGpp synthase I (RelA) to ribosome upon entry of uncharged tRNA. We found that N. gonorrhoeae is highly sensitive to thiostrepton under in vitro conditions, and that thiostrepton, in contrast to other antibiotics, does not induce tolerance or persistence. Finally, we observed that thiostrepton attenuated the expression of key genes involved in the host-pathogen interaction. These properties make thiostrepton a good drug candidate for dampening bacterial virulence and preventing antibiotic tolerance and persistence. The ongoing challenge is to increase the bioavailability of thiostrepton through the use of chemistry and nanotechnology

Cutaneous Metastases from Primary Liver Cancers: The Need for Knowledge and Differential Diagnosis

Primary skin tumors are certainly more frequent than metastatic tumors, but the latter can sometimes be the first sign of otherwise unrecognized neoplastic pathology and always correspond to an advanced stage of the disease. Among the various neoplasms that can metastasize in cutaneous districts, skin metastases from primary malignant neoplasms from the liver and biliary tract are infrequent, and when they do occur they can pose differential diagnosis problems to the pathologist. Here we present two cases of metastatic skin lesions, respectively originating from the liver and the intrahepatic biliary tract, and we conduct a brief review of the current literature

Skin Mycetoma in an 11-Year-Old African Boy: Case Presentation with Emphasis on Histopathological Features and Differential Diagnosis

Mycetoma is an uncommon, chronic infective disease of the skin and subcutaneous tissues, characterized by the triad of tumefaction, draining sinuses, and the presence in the exudate of colonial grains. In cases of long-term disease, the presence of colonial grains together with the host's derivative material can lead to the formation of real sinuses. Histological analysis is of fundamental importance to allow an accurate etiological diagnosis and to understand if the basic pathogen is an actinomycete (bacterium) or a real fungus (eumycetic mycetomas) and is also fundamental for therapy, which is quite different. Here, we present a case of Mycetoma in an 11-year-old patient who emigrated from Djibouti, Somalia, and showed the essential histopathological features of this rare and forgotten nosographic entity in the industrialized world and briefly discuss the major and most important differential diagnoses

Skin Manifestation of SARS-CoV-2: The Italian Experience

At the end of December 2019, a new coronavirus denominated Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) was identified in Wuhan, Hubei province, China. Less than three months later, the World Health Organization (WHO) declared coronavirus disease-19 (COVID-19) to be a global pandemic. Growing numbers of clinical, histopathological, and molecular findings were subsequently reported, among which a particular interest in skin manifestations during the course of the disease was evinced. Today, about one year after the development of the first major infectious foci in Italy, various large case series of patients with COVID-19-related skin manifestations have focused on skin specimens. However, few are supported by histopathological, immunohistochemical, and polymerase chain reaction (PCR) data on skin specimens. Here, we present nine cases of COVID-positive patients, confirmed by histological, immunophenotypical, and PCR findings, who underwent skin biopsy. A review of the literature in Italian cases with COVID-related skin manifestations is then provided

Dedifferentiated Melanoma: A Diagnostic Histological Pitfall! Review of the Literature with Case Presentation

Dedifferentiated melanoma is a particular form of malignant melanoma with a progressive worsening of the patient's clinical outcome. It is well known that melanoma can assume different histo-morphological patterns, to which specific genetic signatures correspond, sometimes but not always. In this review we address the diagnostic difficulties in correctly recognizing this entity, discuss the major differential diagnoses of interest to the dermatopathologist, and conduct a review of the literature with particular attention and emphasis on the latest molecular discoveries regarding the dedifferentiation/undifferentiation mechanism and more advanced therapeutic approaches

Histological Hallmarks of Malignant Melanoma

The histopathological diagnosis of malignant melanoma remains the gold standard to allow the patient to access the entire process of the diagnostic-therapeutic-assistance path. Despite the continuous search for markers that can assist in the diagnostic process, there are cases that remain complex to diagnose, and the presence of different criteria among dermatopathologists further complicates the issue. This section will focus on the state of the art of dermatopathological diagnostics of melanoma, starting from the morphological bases up to the latest acquisitions of immunohistochemistry for diagnostic purposes, and molecular biology for therapeutic purposes. Furthermore, we will focus on particularly “challenging” MM histotypes and on what are the current guidelines for a correct diagnosis

Phenotyping of Fecal Microbiota of Winnie, a Rodent Model of Spontaneous Chronic Colitis, Reveals Specific Metabolic, Genotoxic, and Pro-inflammatory Properties

Abstract Winnie, a mouse carrying a missense mutation in the MUC2 mucin gene, is a valuable model for inflammatory bowel disease (IBD) with signs and symptoms that have multiple similarities with those observed in patients with ulcerative colitis. MUC2 mucin is present in Winnie, but is not firmly compacted in a tight inner layer. Indeed, these mice develop chronic intestinal inflammation due to the primary epithelial defect with signs of mucosal damage, including thickening of muscle and mucosal layers, goblet cell loss, increased intestinal permeability, enhanced susceptibility to luminal inflammation-inducing toxins, and alteration of innervation in the distal colon. In this study, we show that the intestinal environment of the Winnie mouse, genetically determined by MUC2 mutation, selects an intestinal microbial community characterized by specific pro-inflammatory, genotoxic, and metabolic features that could imply a direct involvement in the pathogenesis of chronic intestinal inflammation. We report results obtained by using a variety of in vitro approaches for fecal microbiota functional characterization. These approaches include Caco-2 cell cultures and Caco-2/THP-1 cell co-culture models for evaluation of geno-cytotoxic and pro-inflammatory properties using a panel of 43 marker RNAs assayed by RT-qPCR, and cell-based phenotypic testing for metabolic profiling of the intestinal microbial communities by Biolog EcoPlates. While adding a further step towards understanding the etiopathogenetic mechanisms underlying IBD, the results of this study provide a reliable method for phenotyping gut microbial communities, which can complement their structural characterization by providing novel functional information