Spinal neurofibromatosis without cafe-au-lait macules in two families with null mutations of the NF1 gene.
Spinal neurofibromatosis (SNF) is considered to be an alternative form of neurofibromatosis, showing multiple spinal tumors and cafe-au-lait macules. Involvement of the neurofibromatosis type 1 (NF1) locus has been demonstrated, by linkage analysis, for three families with SNF. In one of them, a cosegregating frameshift mutation in exon 46 of the NF1 gene was identified. In the present study, we report four individuals from two families who carry NF1 null mutations that would be expected to cause NF1. Three patients have multiple spinal tumors and no cafe-au-lait macules, and the fourth has no clinical signs of NF1. In the first family, a missense mutation (Leu2067Pro) in NF1 exon 33 was found, and, in the second, a splice-site mutation (IVS31-5A-->G) enlarging exon 32 by 4 bp at the 5' end was found. The latter mutation has also been observed in an unrelated patient with classical NF1. Both NF1 mutations cause a reduction in neurofibromin of approximately 50%, with no truncated protein present in the cells. This demonstrates that typical NF1 null mutations can result in a phenotype that is distinct from classical NF1, showing only a small spectrum of the NF1 symptoms, such as multiple spinal tumors, but not completely fitting the current clinical criteria for SNF. We speculate that this phenotype is caused by an unknown modifying gene that compensates for some, but not all, of the effects caused by neurofibromin deficiency. (+info)
A homozygous germ-line mutation in the human MSH2 gene predisposes to hematological malignancy and multiple cafe-au-lait spots.
Individuals with a germ-line mutation in one of the DNA mismatch repair (MMR) genes are at significant risk for colorectal cancer and other tumors. Three families have previously been reported with individuals homozygous for mutations in the MMR gene MLH1 that are predicted to compromise MMR. These individuals develop hematological malignancies and/or neurofibromatosis type 1 at an early age. Here, in an individual, we demonstrate that a homozygous novel mutation in the MMR gene MSH2 is associated with leukemia and multiple cafe-au-lait spots, a feature of neurofibromatosis type 1. Because the hematological malignancies observed in the individuals homozygous for the loss of MMR are reflective of the lymphomas seen in mice lacking MMR, the mice may provide a useful model for human neoplasia. (+info)
A case of non-Hodgkin's lymphoma in a patient with neurofibromatosis type 1.
Neurofibromatosis type 1 is characterized by cutaneous neurofibromas and pigmented lesions of the skin called cafe au lait spots. Although neurofibromatosis type 1 represents a major risk factor for the development of malignancy, especially of nervous system tumors, malignant lymphoma rarely occurs in a patients with neurofibromatosis type 1. Recently, a 77-year-old woman with neurofibromatosis type 1 was diagnosed as non-Hodgkin's Lymphoma (diffuse large B cell). She had multiple cafe au lait spots, neurofibromas and right axillary lymph node enlargement. An abdominal CT scan demonstrated a left pelvic mass and para-aortic lymphadenopathy. Because non-Hodgkin's Lymphoma in a neurofibromatosis patient has never been reported in Korea, herein, we describe this case and include a review of the literature. (+info)
Common hyperpigmentation disorders in adults: Part I. Diagnostic approach, cafe au lait macules, diffuse hyperpigmentation, sun exposure, and phototoxic reactions.
The cause of hyperpigmentation usually is traced to the activity and presence of melanocytes. Cafe au lait macules may be solitary benign findings or may indicate the presence of neurofibromatosis with its associated complications. Diffuse hyperpigmentation should prompt a search for offending medications or systemic diseases such as hemochromatosis, hyperthyroidism, and Addison's disease. In these instances, the hyperpigmentation may be ameliorated by discontinuing offending medications, performing serial phlebotomy in patients with hemochromatosis, instituting cause-specific treatments in patients with hyperthyroidism, and replacing deficient glucocorticoids and mineralocorticoids in patients with Addison's disease. Cosmetic treatment with bleaching agents or lasers can be used to decrease pigmentation of ephelides (freckles) and lentigines. (+info)
Cafe au lait has hue of its own.
Segmental pigmentation disorder is a pigmentation disorder (hypo- or hyperpigmentation) first described some 20 years ago. It appears early in life, is segmental, and usually has a sharp border in the midline. It can be confused clinically and histologically with several pigmentary disorders, especially with giant or segmental cafe-au-lait macules. The purpose of this article is to promote, revive, and refresh this somewhat neglected entity, and to further subdivide it into two types: segmental pigmentation disorder simplex and segmental cafe-au-lait. We illustrate our contention with case reports. (+info)
The use of lasers and intense pulsed light sources for the treatment of pigmentary lesions.
Lasers and intense pulsed light sources are frequently used for the treatment of pigmented lesions, and the appropriate selection of devices for different lesions is vital to achieving satisfactory clinical outcomes. In dark-skinned patients, the risk of post-inflammatory hyperpigmentation is of particular importance. In general, long-pulse laser and intense pulsed light sources can be effective with a low risk of post-inflammatory hyperpigmentation (PIH) when used for the treatment of lentigines. However, for dermal pigmentation and tattoo, Q-switched lasers are effective, with a lower risk of complications. In the removal of melanocytic nevi, a combined approach with a long-pulse pigmented laser and a Q-switched laser is particularly applicable. (+info)
Autoimmune haemolysis as an unusual cause of anaemia in von Recklinghausen's disease.
Von Recklinghausen's disease, now classified as neurofibromatosis type 1 (NF-1), is a relatively frequent autosomal dominant disorder and has clinical manifestations, such as cafe-au-lait spots, freckling, generalised cutaneus neurofibroma, Lisch nodules, short stature, optic glioma and central nervous system tumours. In adults, anaemia in the course of NF-1 is usually due to gastrointestinal tumour bleeding. Association of NF-1 and autoimmune haemolytic anaemia is unusual. Here, we report a 48-year-old woman with NF-1 presenting as autoimmune haemolytic anaemia. We also reviewed the literature about the association of NF-1 and autoimmune diseases. (+info)
The use of lasers in the pediatric population.
Over the past 2 decades, there have been numerous advances in laser therapy of birth-marks in the pediatric population. Concerns regarding efficacy, overall benefit, and side-effects linger. We present our opinion, based upon decades of clinical experience, on the role of lasers to treat port wine stains, superficial hemangiomas, and cafe au lait macules in children. (+info)