| dyskeratosis congenita is recognized by its dermal lesions and constitutional aplastic anemia in some cases. We report successful allogeneic bone marrow transplantation in two siblings with this disease from their sister, and their long term follow-up. We used reduced doses of cyclophosphamide and busulfan for conditioning instead of total body irradiation. Also, we report late adverse effects of transplantation which are not distinguishable from the natural course of disease. ( info) |
| We describe a woman with dyskeratosis congenita (DKC), microcephaly, and a purple discoloration of the tongue. The latter findings are not commonly described in males with DKC, have been reported in another female patient with this condition, and may represent the phenotype of an autosomal recessive entity of DKC. Results of x chromosome inactivation studies did not support X-linked DKC in our family. The additional findings of an affected brother and parental consanguinity support the hypothesis of autosomal recessive inheritance. ( info) |
| An 18-year old boy with dyskeratosis congenita is presented. To examine the DNA metabolism of our patient, we applied the comet assay, a simple, quick and sensitive method that so far has not been used in this disease. After exposure to UVB, cells originating from the patient present abnormal dna repair localized in the late step. We consider that such repair deficiency could be related to susceptibility to cancer. The comet assay seems to be a good procedure to investigate dyskeratosis congenita or other genodermatoses. ( info) |
4/40. Overlap of dyskeratosis congenita with the Hoyeraal-Hreidarsson syndrome. X-linked dyskeratosis congenita (DKC) is characterized by mucosal leukoplakia and ulcerations, skin abnormalities, nail dystrophy, and pancytopenia. Hoyeraal-Hreidarsson syndrome (HHS) includes intrauterine growth retardation, microcephaly, mental retardation, cerebellar malformation, and pancytopenia. A patient with striking features of both HHS and DKC has a de novo mutation in the DKC1 gene, known to be responsible for DKC. HHS may be a severe form of DKC, in which affected individuals die before characteristic mucocutaneous features develop. ( info) |
| We report a 28-year-old male with a voluminous growth of the tongue, present for 6 months. The histological examination revealed a squamous cell carcinoma. The patient was also affected by oral leukoplakia, nail dystrophy, reticulated poikiloderma of the neck and hyperkeratosis of palms and soles. On the basis of clinical features and histological findings, as well as findings from the family, the diagnosis of dyskeratosis congenita (DKC) was made. ( info) |
6/40. Multiple intrapulmonary arteriovenous fistulas in childhood. Pulmonary arteriovenous fistulas (AVFs) are a rare but recognized cause of cyanosis in childhood. Lesions may be acquired as in hepatopulmonary syndrome or they may be congenital, particularly in association with certain multisystem disorders. Large fistulas are more common than multiple small connections. Two cases. both boys, presenting in the first decade of life are described. "Bubble" echocardiography was the most telling investigation and strongly suggested the presence of AVFs in both cases. Each patient then underwent cardiac catheterization, which demonstrated normal pulmonary artery pressure and diffuse pulmonary telangiectasis. Both patients were treated effectively with nifedipine and continue with this mode of therapy. ( info) |
| dyskeratosis congenita is a rare multisystem condition involving mainly the ectoderm. It is characterized by a triad of reticular skin pigmentation, nail dystrophy and leukoplakia of mucous membranes. Oral and dental abnormalities may also be present. Complications are a predisposition to malignancy and bone marrow involvement with pancytopenia. The case of a 14-year-old girl is described who presented with several of the characteristic systemic features of this condition, together with the following oral features: hypodontia, diminutive maxillary lateral incisors, delayed dental eruption, crowding in the maxillary premolar region, short roots, poor oral hygiene, gingival inflammation and bleeding, alveolar bone loss, caries and a smooth atrophic tongue with leukoplakia. Although this condition is rare, dental surgeons should be aware of the dental abnormalities that exist and the risk of malignant transformation within the areas of leukoplakia. ( info) |
8/40. One novel and two recurrent missense DKC1 mutations in patients with dyskeratosis congenita (DKC). X-linked dyskeratosis congenita (DKC) is a progressive multisystem disorder most severely affecting tissues with a high cellular turnover such as skin, mucous membranes, and blood. Most patients die of bone marrow failure, although the chances of succumbing to various types of cancer and pulmonary disease are also high. DKC is caused predominantly by missense mutations in the DKC1 gene linked to Xq28. Some of the clinical features are reminiscent of premature ageing and this agrees with recent indications that DKC could be a telomere maintenance disorder. There is considerable variability in the type, severity, and age at onset of the various anomalies. Recognition of this has increased with the finding that patients with Hoyeraal-Hreidarsson syndrome (HHS) who exhibit severe neurological problems in addition to early-onset pancytopenia, also bear mutations in the DKC1 gene. For these reasons, and compounded by the range of mutations, phenotype-genotype correlations and accurate assessments of prognosis have not been possible. To complement the present data, we here report on three new cases of DKC and their mutations. One is a novel mutation in the exon 3 (K43E). The other two represent a frequently recurring mutation in exon 11 (A353V) and a less frequently recurring mutation in the exon 3 (T49M). ( info) |
9/40. Hereditary benign intraepithelial dyskeratosis: Report of two cases with prominent oral lesions. Hereditary benign intraepithelial dyskeratosis is a rare autosomal dominant disorder of the oral and ocular mucosa initially described in the Haliwa-Saponi Native American tribe of north carolina. We describe 2 sisters with the characteristic oral and ocular findings. This entity should be distinguished from several other diseases that cause white lesions in the mouth including white sponge nevus. ( info) |
| dyskeratosis congenita (DC) is a rare inherited multisystem disorder characterised by lesions of the skin and appendages. Bone marrow failure occurs in 80% of patients. The gene for the X-linked form of DC has been identified on Xq28 and designated as DKC1. Pulmonary manifestations have rarely been reported. It is not known whether there is a respiratory disease peculiar to these patients and, if so, whether it is associated with a specific genetic mutation. A 40 year old Egyptian man with pulmonary disease and his symptom free 35 year old brother both presented with mucocutaneous lesions characteristic of DC. In the older brother chest imaging revealed generalised intralobular interstitial thickening and honeycombing. Pulmonary function tests showed a restrictive pattern. Open lung biopsy specimens of lung tissue showed various degrees of fibrosis consistent with usual interstitial pneumonia of chronic idiopathic pulmonary fibrosis. The younger brother was free of pulmonary lesions. Both had a novel missense mutation 5C-->T in exon 1 of the DKC1 gene. It is concluded that pulmonary disease in DC may be underestimated, possibly because most patients die at an early age of bone marrow failure. No relationship between genotype and phenotype could be established in the patients studied. The genetic diagnosis of DC is now available, which may enable it to be diagnosed in patients with restrictive pulmonary disease and minimal cutaneous signs. ( info) |