Reassessment of the NF1 variants of unknown significance found during the 20-year activity of a genetics diagnostic laboratory.

The finding of variants of uncertain significance (VUS) in the activity of a diagnostic genetic laboratory is a common issue, which is however provisional and needs to be periodically re-evaluated, due to the continuous advancements in our knowledge of the genetic diseases. Neurofibromatosis type 1, caused by the occurrence of heterozygous pathogenic NF1 variants, is a good model for studying the evolution of VUS, due to the widespread use of genetic testing for the disease, the constant enrichment of the international databases with NF1 variants and the full adult penetrance of the disease, which makes genotyping the parents a crucial step in the diagnostic workflow. The present study retrospectively reviewed and reinterpreted the genetic test results of NF1 in a diagnostic genetic laboratory in the period from January 1, 2000 to December 31, 2020. All the VUS were reinterpreted using the 2015 consensus standards and guidelines for the interpretation. Out of 589 NF1 genetic tests which were performed in the period, a total of 85 VUS were found and reinterpreted in 72 cases (84.7%): 21 (29.2%) were reclassified as benign/likely benign, whereas 51 (70.8%) were recoded as pathogenic/likely pathogenic with a significant trend distribution (Chi square test for trend p = 0.005). Synonymous VUS have mainly been reclassified as class 1 and 2 (7/8, 87.5%), whereas missense variants have been attributed to class 4 and 5 in 38 out of the 58 cases (65.5%). These findings underline an improvement in the classification of variants over time, suggesting that a reinterpretation of the genetic tests should be routinely performed to support the physicians in the clinical diagnosis of genetic diseases.

Recurrent NF1 gene variants and their genotype/phenotype correlations in patients with Neurofibromatosis type I.

Neurofibromatosis type I, a genetic condition due to pathogenic variants in the NF1 gene, is burdened by a high rate of complications, including neoplasms, which increase morbidity and mortality for the disease. We retrospectively re-evaluated the NF1 gene variants found in the period 2000-2019 and we studied for genotype/phenotype correlations of disease complications and neoplasms 34 variants, which were shared by at least two unrelated families (range 2-11) for a total 141 of probands and 21 relatives affected by Neurofibromatosis type I. Recurrent variants could be ascribed to the most common mutational mechanisms (C to T transition, microsatellite slippage, non-homologous recombination). In genotype/phenotype correlations, the variants p.Arg440*, p.Tyr489Cys, and p.Arg1947*, together with the gross gene deletions, displayed the highest rates of complications. When considering neoplasms, carriers of variants falling in the extradomain region at the 5' end of NF1 had a lower age-related cancer frequency than the rest of the gene sequence, showing a borderline significance (p = 0.045), which was not conserved after correction with covariates. We conclude that (1) hotspots in NF1 occur via different mutational mechanisms, (2) several variants are associated with high rates of complications and cancers, and (3) there is an initial evidence toward a lower cancer risk for carriers of variants in the 5' end of the NF1 gene although not significant at the multivariate analysis.

Italian recommendations on enzymatic debridement in burn surgery.

INTRODUCTION: Nexobrid®, a bromelain-based type of enzymatic debridement, has become more prevalent in recent years. We present the recommendations on enzymatic debridement (Nexobrid®)'s role based on the practice knowledge of expert Italian users. METHODS: The Italian recommendations, endorsed by SIUST (Italian Society of Burn Surgery), on using enzymatic debridement to remove eschars for burn treatment were defined. The definition followed a process to evaluate the level of agreement (a measure of consensus) among selected experts, representing Italian burn centers, concerning defined clinical aspects of enzymatic debridement. The consensus involved a multi-phase process based on the Delphi method. RESULTS: The consensus panel included experts from Italy with a combined experience of 1068 burn patients treated with enzymatic debridement. At the end of round 3 of the Delphi method, the panel reached 100% consensus on 26 out of 27 statements. The panel achieved full, strong consensus (all respondents strongly agreed on the statement) on 24 out of 27 statements. DISCUSSION: The statements provided by the Italian consensus panel represent a "ready to use" set of recommendations for enzymatic debridement in burn surgery that both draw from and complete the existing scientific literature on the topic. These recommendations are specific to the Italian experience and are neither static nor definitive. As such, they will be updated periodically as further quality evidence becomes available.

Evaluation of plasma oxidative stress, with or without antioxidant supplementation, in superficial partial thickness burn patients: a pilot study.

BACKGROUND: Oxidative stress is one of the main causes of pathophysiological alterations observed during burn injury. The present pilot study aimed to determine whether a specific oral antioxidant supplementation could in any way influence free radical blood values in patients affected by superficial partial thickness burns. MATERIALS AND METHODS: Plasma oxidants and plasma antioxidant capacity were analysed in 20 superficial partial thickness burn patients for a 2-week period; patients were randomly divided into two groups, one of which was supported with a specifically designed oral antioxidant formula (Squalene 100 mg, Vitamin C 30 mg, Coenzyme Q10 10 mg, Zinc 5 mg, Beta Carotene 3.6 mg, Bioflavonoids 30 mg, Selenium 55 mcg) administered daily, starting from the day of admission, for the whole study period. RESULTS: No significant differences were found in plasma oxidants and plasma antioxidant capacity between the two groups of patients. CONCLUSIONS: These results did not reflect any significant benefits of an antioxidant oral supplementation at usual dosages when considering oxidative plasmatic values of superficial partial thickness burn patients.

Platelet gel in the treatment of cutaneous ulcers: the experience of the Immunohaematology and Transfusion Centre of Parma.

BACKGROUND: Platelet gel is being ever more frequently used to promote healing of cutaneous ulcers. However, the factors that determine the often variable clinical outcome of this procedure are still incompletely understood. AIMS: The aims of this study were to demonstrate that platelet gel, even when obtained under strictly controlled conditions, produces highly variable outcomes in patients with cutaneous ulcers and to propose a method for in vitro standardisation of the biological properties of platelet gel. MATERIAL AND METHODS.: Patients were enrolled on the basis of a pre-defined protocol. Platelet concentrate was produced with standard methods, with a variability in platelet count among the different samples of less than 10%. The platelet gel for clinical use was obtained, under strictly standardized conditions, by adding thrombin and calcium gluconate to the concentrates. For in vitro studies, platelet gel, obtained from platelet-rich plasma from four donors, was frozen and thawed twice so as to increase gel contraction. The supernatant was used to modify cell proliferation, protein synthesis, and the expression of selected genes in cultures of human diploid fibroblasts. RESULTS: Seventeen patients (aged 44-78 years) with ulcers (4 diabetic, 11 vascular, 1 post-traumatic, 1 decubitus) were treated with platelet gel (4 autologous, 13 homologous). Complete re-epithelialisation of four ulcers (1 diabetic, 1 post-traumatic, 2 vascular) was obtained after applications of platelet gel (2 autologous, 2 homologous); in 11 other cases there was a greater than 50% reduction in the size of the ulcer. Two patients had no benefit. The supernatant of the platelet gel was able to promote dose-dependent proliferation and changes in gene expression as well as in metabolic activities related to protein synthesis. CONCLUSIONS: Although the use of platelet gel in the treatment of cutaneous ulcers is increasing, and conditions for its production are better standardised, very considerable variability of clinical outcomes is still observed, even within single centres, suggesting that there are differences in biological properties of platelet concentrates from individual patients which cannot be readily controlled with current techniques. The biological effects of the platelet gel supernatant described in this article may provide the basis for a simple biological validation of platelet preparations before their clinical use, so as to reduce this potentially important source of variability.

Myiasis of the scalp due to Dermatobia hominis in a traveler returning from Brazil.

This article describes a case of myiasis by Dermatobia hominis diagnosed in a young Italian man returning from a vacation through Brazil. Considering the increasing number of travels to tropical and subtropical areas, clinicians in nonendemic areas must think about the possibility of imported unusual infestations during their daily practice.

[Clinical and nursing protocol in the treatment of the decubital ulcers]. / Protocollo clinico-assistenziale nel trattamento delle ulcere da decubito.

The decubital ulcers treatment needs a complex clinical approach. The ulcer healing and the absence of recurrences are not only the result of a correct surgical operation. The purpose of this work is to identify all the clinical and nursing parameters that can provide long lasting healing. We treated 105 decubital ulcers in various body areas (sacralis, ischiatic, trochanteric and calcanear regions) and we defined a clinical protocol that starts from prevention, to the admission, till the convalescence. We obtained satisfactory results with few post-operative complications and recurrences. Our protocol is widely confirmed by various authors (the radical toilette, the use of fasciocutaneous and musculocutaneous flaps and the importance of nutrition. In particular, the use of easier flaps (cutaneous, fasciocutaneous), is preferred in the first surgical option to leave other more complex techniques (musculocutaneous flap) for the recurrences treatment. Our protocol follows the patient from the first visit till several months after dismission during convalescence. The pre-operative measures (nutritional state correction, infection care, detersion improvement) as well the post-operating ones (use of circulating fluid beds, rest in bed for at least one month) result to be mandatory for a successful outcome.

Overexpansion technique in burn scar management.

Overexpansion techniques are useful in overcoming a shortage of donor site for expansion: the aim of the authors was to verify whether this technique should be chosen instead of serial expansions for creation of wider and more malleable flaps for reconstruction. From 1993 to May 2005 we have overexpanded 59 patients with burn scars. The patients always underwent reconstruction at least 2 years after complete healing. Almost any body region capable of expansion has been overexpanded. The technique is illustrated here in the reconstruction of scalp, neck, trunk and thigh. Tissue expander original volume ranged from 450 to 800 cc: the silicon implant shape was both round and rectangular. Mean overinflation was 3.6 times beyond the stated vendor's maximum volume. The principle ratios were performed in the trunk (4.375) and in the lower extremities (4.125). The largest volume instilled in a single tissue expander was 3,500 cc. Overall expansion length was on average 172.6 days (range: 101-248). All patients were compliant with inflation once a week. The reconstructions were planned as the expansion of a transposition or an advancement flap. All patients had completion of their reconstruction with satisfactory resolution of their problem: complications occurred in three of all hyperinflated prostheses. Tissue overexpansion, if carefully planned and conducted, allows the completion of reconstruction in one-stage. Instead of serial expansions, it enhances patient compliance and reduces cost.