Hypercalcemic hyperparathyroidism and hypophosphatemic osteomalacia complicating neurofibromatosis

Summary Neurofibromatosis is sometimes complicated by impaired renal tubular reabsorption of phosphate, hypophosphatemia, and osteomalacia. Hyperparathyroidism has also been reported in patients with neurofibromatosis. When hypercalcemia and elevated levels of parathyroid hormone are found in osteomalacia, however, it may be difficult to determine if the hyperparathyroidism was primary or tertiary. We describe a patient with neurofibromatosis, hypercalcemic hyperparathyroidism, hypophosphatemic osteomalacia, vitamin D deficiency, and clear-cell hyperplasia of all four parathyroid glands. Serial biomechanical, bone biopsy, and densitometric studies confirmed that treatment with ergocalciferol, calcium, and phosphate supplements significantly improved the osteomalacia but caused increased parathyroid overactivity. After subtotal parathyroidectomy, the parathyroid hormone concentration became normal and the bone mineral content increased at the spine and hip, but inappropriate phosphaturia persisted. The findings indicate that hyperparathyroidism, osteomalacia, and vitamin D deficiency adversely affect each other.     

Malignant evolution of presumed benign lesions in the brain in neurofibromatosis: case report

We report a patient suffering from neurofibromatosis type 1 in whom neoplasms developed from the areas of altered signal which are generally considered benign and typical of the disease. MRI, despite two previous examinations 3 and 2 years before development of the tumour, gave no clue to an unfavourable outcome. Received: 18 January 1996 Accepted: 24 October 1996     

Spontaneous regression of optic pathways gliomas in three patients with neurofibromatosis type I and critical review of the literature

Case reports The authors report their experience about three children (two girls, one boy; average age 1.6 years) with a spontaneous regression of optic gliomas. All of them had a previous diagnosis of neurofibromatosis type 1 (NF 1). None of them underwent surgery or biopsy nor received chemotherapy or radiotherapy. The complete regression was documented by MRI scans performed during a mean follow-up of 6.3 years.Literature review Moreover, the authors analyze the features of the 16 cases previously reported in English literature of spontaneously regressed optic gliomas with an overview of the different therapeutic strategies. The knowledge that this kind of tumor, particularly in young patients, may regress is important in the decision of the best therapeutic approach.     

Neurogenic polyps

A neoplastic proliferation of peripheral nerve sheath cells (Schwann cells, fibroblasts and perineurial cells) and ganglion cells in the colorectum may give rise to the mucosal or submucosal polyps. Depending upon the predominant cell types, these neurogenic polyps can be classified as schwannomas, granular cell tumours, neurofibromas, perineuriomas, mixed nerve sheath tumours, ganglioneuromas or paragangliomas. Morphologically, the neoplastic cells repeat or mimic the corresponding nerve sheath cells or neurons in terms of growth pattern, histology and immunoreactivity. They are uncommon, but the polyps can occur in any age group, although the vast majority of patients are adults. The polyps can be either solitary (most peripheral nerve sheath tumours) or multiple, especially if associated with systemic diseases (i.e. syndromes involving the peripheral nerve tissue). They are usually incidental findings or may be accompanied by gastrointestinal symptoms. Almost all colorectal neurogenic polyps are benign, and they rarely undergo malignant transformation unless they are part of a syndromatic manifestation. However, these polyps may cause a diagnostic problem during screening for colorectal cancer. An accurate diagnosis of these entities will help clinicians to make appropriate management decisions.     

Resolution of spinal epidural vascular pseudotumor following balloon occlusion of a postoperative vertebral arteriovenous fistula

Summary We describe a case of a vascular mass arising secondary to a postoperative vertebral arteriovenous fistula mimicking recurrent cervical neurofibroma on CT in a patient with neurofibromatosis. Angiography was required for diagnosis. The recurrent tumor resolved following balloon embolization of the fistula.     

COVID-19 in people with neurofibromatosis 1, neurofibromatosis 2, or schwannomatosis

PurposePeople with pre-existing conditions may be more susceptible to severe COVID-19 when infected by SARS-CoV-2. The relative risk and severity of SARS-CoV-2 infection in people with rare diseases such as neurofibromatosis type 1 (NF1), neurofibromatosis type 2 (NF2), or schwannomatosis (SWN) is unknown.MethodsWe investigated the proportions of people with NF1, NF2, or SWN in the National COVID Cohort Collaborative (N3C) electronic health record data set who had a positive test result for SARS-CoV-2 or COVID-19.ResultsThe cohort sizes in N3C were 2501 (NF1), 665 (NF2), and 762 (SWN). We compared these with N3C cohorts of patients with other rare diseases (98-9844 individuals) and the general non-NF population of 5.6 million. The site- and age-adjusted proportion of people with NF1, NF2, or SWN who had a positive test result for SARS-CoV-2 or COVID-19 (collectively termed positive cases) was not significantly higher than in individuals without NF or other selected rare diseases. There were no severe outcomes reported in the NF2 or SWN cohorts. The proportion of patients experiencing severe outcomes was no greater for people with NF1 than in cohorts with other rare diseases or the general population.ConclusionHaving NF1, NF2, or SWN does not appear to increase the risk of being SARS-CoV-2 positive or of being a patient with COVID-19 or of developing severe complications from SARS-CoV-2.     

CT detection of basal ganglion lesions in neurofibromatosis type 1: correlation with MRI

Summary Prospective study of CT and MRI in 41 consecutive children with suspected type 1 neurofibromatosis revealed basal ganglion lesions on T2-weighted spin echo images in 22 cases (54%) and on CT in only 7 of those (32%). T2-weighted spin-echo MRI also revealed multiple signal changes in the supra- and infratentorial white matter and brain stem that went completely unnoticed on CT.     

Occlusion of the cerebral arteries in Recklinghausen's disease

Summary Two children, aged 18 months and 6 years, who had Recklinghausen's disease, had occlusion of cerebral arteries. One child had no motor deficit but the other had right hemiparesis and partial occlusion of the left posterior cerebral artery, a fact not found in the literature.     

头颈部遗传性肿瘤概述

头颈部遗传性肿瘤主要包括家族性头颈部副神经节瘤、多发性内分泌腺瘤病1型、多发性内分泌腺瘤病2型、家族性甲状旁腺功能亢进、家族性甲状腺乳头状癌、神经纤维瘤病I型、神经纤维瘤病II型、家族性鼻咽癌及家族性鳞状细胞癌。本文从头颈部遗传性肿瘤的分类、临床特征、遗传学和治疗等方面做一综述。     

Sudden death due to rupture of the right internal carotid artery in neurofibromatosis type 1: A case report

Vascular involvement is a well-recognized manifestation of neurofibromatosis type 1 (NF1) which has the potential to be fatal when disrupted. We here present a case of sudden death due to the fatal arterial rupture resulted from infiltration of the neurofibromas. A 42-year-old man who suffered from NF1 presented a 1-h history of sudden onset of pain in his right cervical region. His condition worsened and became unconscious on his way to the emergency room. Despite resuscitation efforts, he died 30 min later without regaining consciousness. Autopsy examination showed that a neurofibroma located around the right internal carotid artery, confirmed immunohistochemically with S-100, vimentin and CD34. Furthermore, proliferation of spindle cells positive for S-100 was seen in the wall of right internal carotid artery, which was disrupted and resulted in a hemorrhage. These findings suggest that the artery was disrupted by neurofibromas in the vascular wall, which led to fragility of the vessel. On the basis of these findings, we concluded that the cause of death was asphyxia resulting from airway obstruction compressed by the hematoma due to the arterial rupture. As the locality of the neurofibroma and hemorrhage were closed to the carotid baroreflex, we considered another possible mechanism of his sudden death, which could be cardiac inhibition induced by vagal stimulation. We hope this case will increase recognition of NF-1 vasculopathy when encountering any sudden death in NF1 patients.