New insights into the comorbid conditions of Turner syndrome: results from a long-term monocentric cohort study.

PURPOSE: Many questions concerning Turner syndrome (TS) remain unresolved, such as the long-term complications and, therefore, the optimal care setting for adults. The primary aim of this long-term cohort study was to estimate the incidence of comorbid conditions along the life course. METHODS: A total of 160 Italian patients with TS diagnosed from 1967 to 2010 were regularly and structurally monitored from the diagnosis to December 2019 at the University Hospital of Bologna using a structured multidisciplinary monitoring protocol. RESULTS: The study cohort was followed up for a median of 27 years (IQR 12-42). Autoimmune diseases were the comorbid condition with the highest incidence (61.2%), followed by osteoporosis and hypertension (23.8%), type 2 diabetes (16.2%) and tumours (15.1%). Median age of onset ranged from 22 years for autoimmune diseases to 39 years for type 2 diabetes. Malignant tumours were the most prominent type of neoplasm, with a cumulative incidence of 11.9%. Papillary thyroid carcinoma was the most common form of cancer, followed by skin cancer and cancer of the central nervous system. Only one major cardiovascular event (acute aortic dissection) was observed during follow-up. No cases of ischaemic heart disease, heart failure, stroke or death were recorded. CONCLUSIONS: This cohort study confirms the need for continuous, structured and multidisciplinary lifelong monitoring of TS, thus ensuring the early diagnosis of important comorbid conditions, including cancer, and their appropriate and timely treatment. In addition, these data highlight the need for the increased surveillance of specific types of cancer in TS, including thyroid carcinoma.

Chloracne: a case series on cutaneous expression of CYP1A1 as diagnostic biomarker.

Chloracne, also known as metabolizing acquired dioxin-induced skin hamartomas (MADISH), is a rare disfiguring disease related to dioxin exposure. There is a paucity of literature on the clinical manifestations and pathogenesis of chloracne/MADISH. The aim of this study was to assess the clinical features of this very unusual acneiform eruption and to explore the pathogenesis of the disease. This was a retrospective, observational report study was conducted on five patients belonging to the same nuclear family (father, mother and three children) and a relative (father's brother) living in the same house. Histopathological, immunohistochemical, laboratory and toxicological analyses were performed for all patients. The results suggest that CYP1A1 in human skin is a diagnostic biomarker in chloracne, and was positive for all the patients in our sample. Tetrachlorodibenzo-p-dioxin is the most investigated dioxin responsible for chloracne; however, several other agonists, whether dioxin-like or not, can activate the aryl hydrocarbon receptor. To our knowledge, this Italian case series is the first study to suggest polychlorinated biphenyls as a possible cause of an overstimulation of aryl hydrocarbons causing the consequent acneiform eruption.

'Colouring' wipes phenomenon: a peculiar skin pigmentation induced by ascorbic acid observed during lockdown.

During the SARS-CoV-2 (COVID-19) pandemic, an unusual outbreak of yellow-brown pigmentation on the skin of children was reported. Because of the restrictions on movement promulgated during the lockdown, most consultancies were performed using teledermatology. Data concerning personal care products and application of topical substances were collected, which revealed use of the same brand of wipes for all patients. A liquid chromatography-mass spectrometry analysis was performed to compare the components of the wipes before and after the observation of the pigmentation, in order to detect the responsible substance. This analysis revealed a level about 10-fold higher than normal of ascorbic acid and its oxidation products (dehydroascorbic acid and L-threonic acid) in the wipes associated with the pigmentation. These 'colouring wipes' represent a peculiar but harmless phenomenon that highlights the importance of careful questioning about personal care products used by patients.

Major cluster of paediatric 'true' primary chilblains during the COVID-19 pandemic: a consequence of lifestyle changes due to lockdown.

BACKGROUND: Over the last months, during the COVID-19 pandemic, a growing number of chilblain-like lesions were reported mainly in children and rarely in young adults. The relationship with SARS-CoV-2 infection was postulated, often without any laboratory, instrumental or clinical confirmation. The disclosure of information about chilblain-like lesions as a COVID-19 manifestation in social media has created concern in children's families and paediatricians. OBJECTIVES: To verify whether the chilblain-like lesions were caused by SARS-CoV-2 infection. METHODS: Prospective study on a case series including children who presented with acral lesions at the Pediatric Dermatology Outpatient and Pediatric Emergency Unit of the University of Bologna, from 1 April to 30 April 2020. We reported demographical, laboratory and clinical features, history of close contact with COVID-19 patients, presence of similar skin lesions in other family members, precipitating and risk factors for chilblain onset. RESULTS: We evaluated eight patients (five females, three males) aged between 11 and 15 years. We excluded acute or previous SARS-CoV-2 infection with RT-PCR nasopharyngeal swab, serum antibody levels using chemiluminescent immunoassays. Other acute infections causing purpuric lesions at the extremities were negative in all patients. Skin lesion biopsy for histological and immunohistochemical evaluation was made in two cases and was consistent with chilblain. PCR assay on skin lesion biopsy for parvovirus B19, Mycoplasma pneumoniae and SARS-CoV-2 was performed in a patient and resulted negative. We identified common precipitating and risk factors: physical (cold and wet extremities, low BMI), cold and wet indoor and outdoor environment, behaviours, habits and lifestyle. We therefore reached a diagnosis of primary chilblains. CONCLUSIONS: During the COVID-19 pandemic, a 'cluster' of primary chilblains developed in predisposed subjects, mainly teenagers, due to cold exposure in the lockdown period. Laboratory findings support our hypothesis, although it is also possible that an unknown infectious trigger may have contributed to the pathogenesis.

Pigmented fungiform lingual papillae: dermoscopic and clinical features.

The tongue is covered by fungiform, filiform and circumvallate papillae. Fungiform papillae may be mainly pigmented in dark-skinned individuals. A single-centre study aimed to examine the clinical and dermoscopic features of pigmented fungiform papulae of the tongue (PFPT) in children, and a concise review of the literature has been performed. The clinical and anamnestic data of eight children affected by PFPT visited at the Pediatric Dermatology Unit of Bologna between 2010 and 2017, and a systemic review of all studies of PFPT published on PubMed up to 31 August 2017 has been collected and analysed. The results of our data were consistent with the literature review: dark brown to black coloured pinhead papules or bumps were observed in all cases of PFPT, and three types of clinical patterns have been detected. Moreover, the dermoscopic examination showed a cobblestone-like distribution and rose petal pattern. PFPT could be associated with hyperpigmentation of other sites such as the proximal nail folds and gums, and an intrafamiliar transmission is also possible. Clinical and dermoscopic features of PFPT may help clinicians to recognize this ethnic, acquired and benign condition.

Particle-induced osteolysis is not accompanied by systemic remodeling but is reflected by systemic bone biomarkers.

Particle-induced osteolysis is caused by an imbalance in bone resorption and formation, often leading to loss of implant fixation. Bone remodeling biomarkers may be useful for identification of osteolysis and studying pathogenesis, but interpretation of biomarker data could be confounded if local osteolysis engenders systemic bone remodeling. Our goal was to determine if remote bone remodeling contributes to biomarker levels. Serum concentrations of eight biomarkers and bone remodeling rates at local (femur), contiguous (tibia), and remote (humerus and lumbar vertebra) sites were evaluated in a rat model of particle-induced osteolysis. Serum CTX-1, cathepsin K, PINP, and OPG were elevated and osteocalcin was suppressed in the osteolytic group, but RANKL, TRAP 5b, and sclerostin were not affected at the termination of the study at 12 weeks. The one marker tested longitudinally (CTX-1) was elevated by 3 weeks. We found increased bone resorption and decreased bone formation locally, subtle differences in contiguous sites, but no differences remotely at 12 weeks. Thus, the skeletal response to local particle challenge was not systemic, implying that the observed differences in serum biomarker levels reflect differences in local remodeling.

Pharmacologic augmentation of implant fixation in osteopenic bone.

Osteoporosis presents a challenge for successful implant fixation due to an impaired healing response. Preclinical studies have consistently reported reduced osseointegration capability in trabecular bone. Although clinical studies of implant success in dentistry have not found a negative effect due to osteoporosis, low bone mass is a significant risk factor for implant migration in orthopedics. Pharmacologic treatment options that limit bone resorption or upregulate formation have been studied preclinically. While, both treatment options improve implant fixation, direct comparisons to-date have found anti-catabolic more effective than anabolic treatments for establishing implant fixation, but combination approaches are better than either treatment alone. Clinically, anti-catabolic treatments, particularly bisphosphonates have been shown to increase the longevity of implants, while limited clinical evidence on the effects of anabolic treatment exists. Preclinical experiments are needed to determine the effects of osteoporosis and subsequent treatment on the long-term maintenance of fixation and recovery after bone loss.

Healing of rat femoral segmental defect with bone morphogenetic protein-2: a dose response study.

OBJECTIVE: Use of recombinant human bone morphogenetic protein-2 (rhBMP-2) is becoming a common clinical approach to enhance bone repair. There is little or no information in the literature on the dose of rhBMP-2 required for effective healing of critical-sized defects such as those associated with trauma. In this study, we used a segmental defect model to assess the dose response of rhBMP-2 using quantitative and qualitative endpoints. METHODS: Femoral defects in rats were replaced with absorbable collagen sponges carrying rhBMP-2 (0, 1, 5, 10 or 20 µg; N=5). At 4-weeks new bone formation was assessed using quantitative (radiography and microcomputed tomography) and qualitative (histology and backscattered-SEM) endpoints statistically compared. RESULTS: rhBMP-2 showed increased bridging in the gap. Quantitative evaluation presented a bi-phasic dose response curve. Histological assessment revealed that with rhBMP-2 the defect showed the presence of spongy bone with the trabeculae layered with active osteoblasts and osteoclasts. The density and compactness of the bone varied with the dose of rhBMP-2. CONCLUSIONS: Our findings revealed that all doses of rhBMP-2 result in new bone formation. However, there is an optimum dose of 12 µg of rhBMP-2 for bone repair in this model, above which and below which less stimulation of bone occurs.

Limitations of using micro-computed tomography to predict bone-implant contact and mechanical fixation.

Fixation of metallic implants to bone through osseointegration is important in orthopaedics and dentistry. Model systems for studying this phenomenon would benefit from a non-destructive imaging modality so that mechanical and morphological endpoints can more readily be examined in the same specimens. The purpose of this study was to assess the utility of an automated microcomputed tomography (µCT) program for predicting bone-implant contact (BIC) and mechanical fixation strength in a rat model. Femurs in which 1.5-mm-diameter titanium implants had been in place for 4 weeks were either embedded in polymethylmethacrylate (PMMA) for preparation of 1-mm-thick cross-sectional slabs (16 femurs: 32 slabs) or were used for mechanical implant pull-out testing (n= 18 femurs). All samples were scanned by µCT at 70 kVp with 16 µm voxels and assessed by the manufacturer's software for assessing 'osseointegration volume per total volume' (OV/TV). OV/TV measures bone volume per total volume (BV/TV) in a 3-voxel-thick ring that by default excludes the 3 voxels immediately adjacent to the implant to avoid metal-induced artefacts. The plastic-embedded samples were also analysed by backscatter scanning electron microscopy (bSEM) to provide a direct comparison of OV/TV with a well-accepted technique for BIC. In µCT images in which the implant was directly embedded within PMMA, there was a zone of elevated attenuation (>50% of the attenuation value used to segment bone from marrow) which extended 48 µm away from the implant surface. Comparison of the bSEM and µCT images showed high correlations for BV/TV measurements in areas not affected by metal-induced artefacts. In addition for bSEM images, we found that there were high correlations between peri-implant BV/TV within 12 µm of the implant surface and BIC (correlation coefficients ≥0.8, p < 0.05). OV/TV as measured on µCT images was not significantly correlated with BIC as measured on the corresponding bSEM images. However, OV/TV was significantly, but weakly, correlated with implant pull-out strength (r= 0.401, p= 0.049) and energy to failure (r= 0.435, p= 0.035). Thus, the need for the 48-µm-thick exclusion zone in the OV/TV program to avoid metal-induced artefacts with the scanner used in this study means that it is not possible to make bone measurements sufficiently close to the implant surface to obtain an accurate assessment of BIC. Current generation laboratory-based µCT scanners typically have voxel sizes of 6-8 µm or larger which will still not overcome this limitation. Thus, peri-implant bone measurements at these resolutions should only be used as a guide to predict implant fixation and should not be over-interpreted as a measurement of BIC. Newer generation laboratory-based µCT scanners have several improvements including better spatial resolution and X-ray sources and appear to have less severe metal-induced artefacts, but will need appropriate validation as they become available to researchers. Regardless of the µCT scanner being used, we recommend that detailed validation studies be performed for any study using metal implants because variation in the composition and geometry of the particular implants used may lead to different artefact patterns.